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

ERIC Educational Resources Information Center

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…

Measures of physical and cognitive function and work status among individuals with multiple sclerosis: a review of the literature.

PubMed

Pompeii, Lisa A; Moon, Samuel D; McCrory, Douglas C

2005-03-01

The purpose of this review was to critically evaluate the multiple sclerosis (MS) literature that has examined physical and cognitive function in relation to ability to work. Although numerous factors may be considered when determining work ability, physical and/or cognitive functional limitations associated with MS are presumably the primary determinants of work capacity. An exhaustive search of the literature produced 20 research articles that described 18 studies. Findings from these studies support that limitations in physical or cognitive function can hinder one's ability to work; however, ability to work could not be based solely on these measures of function. Work ability among individuals extended beyond measures of impairment to include level of education, job characteristics, and disease symptoms such as fatigue. In summary, measures of physical and cognitive function can guide physicians when clinically evaluating an individual with MS, but are poor indicators for precluding an individual from working.

Composition and work function relationship in Os–Ru–W ternary alloys

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

Swartzentruber, Phillip D.; Detisch, Michael J.; Balk, T. John, E-mail: john.balk@uky.edu

2015-03-15

Os–Ru thin films with varying concentrations of W were sputter deposited in order to investigate their structure–property relationships. The films were analyzed with x-ray diffraction to investigate their crystal structures, and a Kelvin probe to investigate their work functions. An Os–Ru–W film with ∼30 at. % W yielded a work function maximum of approximately 5.38 eV. These results align well with other studies that found work function minima from thermionic emission data on M-type cathodes with varying amounts of W in the coatings. Furthermore, the results are consistent with other work explaining energy-level alignment and charge transfer of molecules on metalmore » oxides. This may shed light on the mechanism behind the “anomalous effect” first reported by Zalm et al., whereby a high work function coating results in a low work function for emitting cathode surfaces. An important implication of this work is the potential for the Kelvin probe to evaluate the effectiveness of dispenser cathode coatings.« less

Social Aspects of the Workplace Among Individuals With Bipolar Disorder.

PubMed

O'Donnell, Lisa; Himle, Joseph A; Ryan, Kelly; Grogan-Kaylor, Andrew; McInnis, Melvin G; Weintraub, Jenna; Kelly, Marisa; Deldin, Patricia

2017-01-01

Bipolar disorder (BD) is characterized by recurrent mood episodes and profound impairments in psychosocial functioning. Occupational disability is one of the most problematic impairments for individuals with BD due to high rates of unemployment and work impairments. Current evidence indicates that social stressors at work-such as social isolation, conflict with others, and stigmas-are common experiences for employed individuals with BD. Yet, few studies have examined the relationship between social stressors at work and overall occupational functioning, instead focusing on individual clinical features of the disorder. This cross-sectional study employed logistic and linear regressions to determine which demographic variables, mood symptoms, and social aspects of the work environment (exclusion, conflict, social support, stigma) were associated with work status (working vs. not working) and work functioning for individuals with bipolar disorder I and II. Greater stigma and exclusion at work ( p < .05) are associated with unemployment among adult individuals with BD, and higher degrees of depression and conflict at work ( p < .05) are associated with work impairments for employed individuals. By examining two distinct measures of work outcomes (work status and work functioning) within the same group of participants, this study provides a unique insight, revealing that predictors of occupational functioning vary based on the specific measure of work outcomes used. This study also emphasizes the need for treatments that address the clinical features of BD and intervene in the work environment to improve functioning and prevent unemployment among individuals with BD.

Socioeconomic inequalities in physical and mental functioning of Japanese civil servants: explanations from work and family characteristics.

PubMed

Sekine, Michikazu; Chandola, Tarani; Martikainen, Pekka; Marmot, Michael; Kagamimori, Sadanobu

2006-07-01

Poor physical and mental functioning is more common among people of low socioeconomic status (SES) and those with disadvantaged work and family characteristics. This study aims to clarify whether the SES inequalities in functioning can be explained by the SES differences in work and family characteristics. The subjects were 3787 male and female civil servants, aged 20-65, working in a local government on the west coast of Japan. Logistic regression analysis was performed to examine (1) whether there were employment-grade (SES) differences in poor physical and mental functioning as measured by the Short Form 36 (SF-36) and (2) whether these SES differences were explained by work and family characteristics. In general, low control at work, high demands, low social support, short and long work hours, shift work, being unmarried, high family-to-work conflict and high work-to-family conflict were independently associated with poor physical and mental functioning in both men and women. In men, the age-adjusted odds ratio (OR) of low-grade employees for poor physical functioning was 1.93 (95% confidence interval: 1.38-2.69) in comparison to high-grade employees. The grade difference was mildly attenuated, when adjusted for work and family characteristics (OR = 1.72)(1.20-2.47). The age-adjusted OR of the low-grade employees for poor mental functioning was 1.88 (1.29-2.74). The grade difference was attenuated and no longer significant when adjusted for work and family characteristics (OR = 1.51)(0.99-2.31). Among women, there were no significant grade-differences in poor physical and mental functioning. Although longitudinal research is necessary to clarify the causal nature of these associations, improvements in SES differences in work and family characteristics may be important for reducing SES inequalities in physical and mental functioning among Japanese men. The different patterns of SES inequalities in health between men and women deserve further research.

Improving measures of work-related physical functioning.

PubMed

McDonough, Christine M; Ni, Pengsheng; Peterik, Kara; Marfeo, Elizabeth E; Marino, Molly E; Meterko, Mark; Rasch, Elizabeth K; Brandt, Diane E; Jette, Alan M; Chan, Leighton

2017-03-01

To expand content of the physical function domain of the Work Disability Functional Assessment Battery (WD-FAB), developed for the US Social Security Administration's (SSA) disability determination process. Newly developed questions were administered to 3532 recent SSA applicants for work disability benefits and 2025 US adults. Factor analyses and item response theory (IRT) methods were used to calibrate and link the new items to the existing WD-FAB, and computer-adaptive test simulations were conducted. Factor and IRT analyses supported integration of 44 new items into three existing WD-FAB scales and the addition of a new 11-item scale (Community Mobility). The final physical function domain consisting of: Basic Mobility (56 items), Upper Body Function (34 items), Fine Motor Function (45 items), and Community Mobility (11 items) demonstrated acceptable psychometric properties. The WD-FAB offers an important tool for enhancement of work disability determination. The FAB could provide relevant information about work-related functioning for initial assessment of claimants; identifying denied applicants who may benefit from interventions to improve work and health outcomes; enhancing periodic review of work disability beneficiaries; and assessing outcomes for policies, programs and services targeting people with work disability.

Silver nanoparticles with tunable work functions

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

Wang, Pangpang, E-mail: pangpang@molecular-device.kyushu-u.ac.jp; Tanaka, Daisuke; Ryuzaki, Sou

To improve the efficiencies of electronic devices, materials with variable work functions are required to decrease the energy level differences at the interfaces between working layers. Here, we report a method to obtain silver nanoparticles with tunable work functions, which have the same silver core of 5 nm in diameter and are capped by myristates and 1-octanethoilates self-assembled monolayers, respectively. The silver nanoparticles capped by organic molecules can form a uniform two-dimensional sheet at air-water interface, and the sheet can be transferred on various hydrophobic substrates. The surface potential of the two-dimensional nanoparticle sheet was measured in terms of Kelvin probemore » force microscopy, and the work function of the sheet was then calculated from the surface potential value by comparing with a reference material. The exchange of the capping molecules results in a work function change of approximately 150–250 meV without affecting their hydrophobicity. We systematically discussed the origin of the work function difference and found it should come mainly from the anchor groups of the ligand molecules. The organic molecule capped nanoparticles with tunable work functions have a potential for the applications in organic electronic devices.« less

Improving Measures of Work-Related Physical Functioning

PubMed Central

McDonough, Christine M.; Ni, Pengsheng; Peterik, Kara; Marfeo, Elizabeth E.; Marino, Molly E.; Meterko, Mark; Rasch, Elizabeth K; Brandt, Diane E.; Jette, Alan M; Chan, Leighton

2016-01-01

Purpose To expand content of the physical function domain of the Work Disability Functional Assessment Battery (WD-FAB), developed for the US Social Security Administration’s (SSA) disability determination process. Methods Newly developed questions were administered to 3,532 recent SSA applicants for work disability benefits and 2,025 US adults. Factor analyses and item response theory (IRT) methods were used to calibrate and link the new items to existing WD-FAB, and computer-adaptive test simulations were conducted. Results Factor and IRT analyses supported integration of 44 new items into 3 existing WD-FAB scales and the addition of a new 11-item scale (Community Mobility). The final physical function domain consisting of: Basic Mobility (56 items), Upper Body Function (34 items), Fine Motor Function (45 items), and Community Mobility (11 items) demonstrated acceptable psychometric properties. Conclusions The WD-FAB offers an important tool for enhancement of work disability determination. The FAB could provide relevant information about work-related functioning for initial assessment of claimants, identifying denied applicants who may benefit from interventions to improve work and health outcomes; enhancing periodic review of work disability beneficiaries; and assessing outcomes for policies, programs and services targeting people with work disability. PMID:28005243

Neuro-Cognitive Intervention for Working Memory: Preliminary Results and Future Directions.

PubMed

Bree, Kathleen D; Beljan, Paul

2016-01-01

Definitions of working memory identify it as a function of the executive function system in which an individual maintains two or more pieces of information in mind and uses that information simultaneously for some purpose. In academics, working memory is necessary for a variety of functions, including attending to the information one's teacher presents and then using that information simultaneously for problem solving. Research indicates difficulties with working memory are observed in children with mathematics learning disorder (MLD) and reading disorders (RD). To improve working memory and other executive function difficulties, and as an alternative to medication treatments for attention and executive function disorders, the Motor Cognition(2)® (MC(2)®)program was developed. Preliminary research on this program indicates statistically significant improvements in working memory, mathematics, and nonsense word decoding for reading. Further research on the MC(2)® program and its impact on working memory, as well as other areas of executive functioning, is warranted.

Effect of nanoscale size and medium on metal work function in oleylamine-capped gold nanocrystals

NASA Astrophysics Data System (ADS)

Abdellatif, M. H.; Ghosh, S.; Liakos, I.; Scarpellini, A.; Marras, S.; Diaspro, A.; Salerno, M.

2016-02-01

The work function is an important material property with several applications in photonics and optoelectronics. We aimed to characterize the work function of clusters resulting from gold nanocrystals capped with oleylamine surfactant and drop-casted onto gold substrate. We used scanning Kelvin probe microscopy to investigate the work function, and complemented our study mainly with X-ray diffraction and X-ray photoelectron spectroscopy. The oleylamine works as an electron blocking layer through which the electrical conduction takes place by tunneling effect. The surface potential appears to depend on the size of the clusters, which can be ascribed to their difference in effective work function with the substrate. The charge state of gold clusters is discussed in comparison with theory, and their capacitance is calculated from a semi-analytical equation. The results suggest that at the nanoscale the work function is not an intrinsic property of a material but rather depends on the size and morphology of the clusters, including also effects of the surrounding materials.

Electron work function–a promising guiding parameter for material design

PubMed Central

Lu, Hao; Liu, Ziran; Yan, Xianguo; Li, Dongyang; Parent, Leo; Tian, Harry

2016-01-01

Using nickel added X70 steel as a sample material, we demonstrate that electron work function (EWF), which largely reflects the electron behavior of materials, could be used as a guide parameter for material modification or design. Adding Ni having a higher electron work function to X70 steel brings more “free” electrons to the steel, leading to increased overall work function, accompanied with enhanced e−–nuclei interactions or higher atomic bond strength. Young’s modulus and hardness increase correspondingly. However, the free electron density and work function decrease as the Ni content is continuously increased, accompanied with the formation of a second phase, FeNi3, which is softer with a lower work function. The decrease in the overall work function corresponds to deterioration of the mechanical strength of the steel. It is expected that EWF, a simple but fundamental parameter, may lead to new methodologies or supplementary approaches for metallic materials design or tailoring on a feasible electronic base. PMID:27074974

Low work function, stable thin films

DOEpatents

Dinh, Long N.; McLean, II, William; Balooch, Mehdi; Fehring, Jr., Edward J.; Schildbach, Marcus A.

2000-01-01

Generation of low work function, stable compound thin films by laser ablation. Compound thin films with low work function can be synthesized by simultaneously laser ablating silicon, for example, and thermal evaporating an alkali metal into an oxygen environment. For example, the compound thin film may be composed of Si/Cs/O. The work functions of the thin films can be varied by changing the silicon/alkali metal/oxygen ratio. Low work functions of the compound thin films deposited on silicon substrates were confirmed by ultraviolet photoelectron spectroscopy (UPS). The compound thin films are stable up to 500.degree. C. as measured by x-ray photoelectron spectroscopy (XPS). Tests have established that for certain chemical compositions and annealing temperatures of the compound thin films, negative electron affinity (NEA) was detected. The low work function, stable compound thin films can be utilized in solar cells, field emission flat panel displays, electron guns, and cold cathode electron guns.

Reversible and non-reversible changes in nanostructured Si in humid atmosphere

NASA Astrophysics Data System (ADS)

Zhigalov, V.; Pyatilova, O.; Timoshenkov, S.; Gavrilov, S.

2014-12-01

Atmosphere water influence in the nanostructured silicon (NSS) was investigated by IR-spectroscopy and electron work function measurement. Long-term non-reversible dynamics of IR-spectra was found as a result of 100% humidity influence on the nanostructured silicon. It was indicated that air humidity affects on the work function. Dynamics of the electron work function consists of reversible and non-reversible components. Reversible component appears as strong anti-correlation between work function and humidity. Work function change of NSS is about 0.4 eV while the humidity changes between 0% and 100%. Reversible component can be explained by physical sorption of water molecules on the surface. Non-reversible component manifests as long-term decreasing trend of work function in humid atmosphere. Transition curve during abruptly humidity changes alters its shape. Non-reversible component can be explained by chemisorption of water.

Coverage dependent work function of graphene on a Cu(111) substrate with intercalated alkali metals

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

Cook, Brandon G.; Russakoff, Arthur; Varga, Kalman

2015-05-26

Using first-principles calculations, it is shown that the work function of graphene on copper can be adjusted by varying the concentration of intercalated alkali metals. Using density functional theory, we calculate the modulation of work function when Li, Na, or K are intercalated between graphene and a Cu(111) surface. Furthermore, the physical origins of the change in work function are explained in terms of phenomenological models accounting for the formation and depolarization of interfacial dipoles and the shift in the Fermi-level induced via charge transfer.

Risk factors for poor work functioning of persons with schizophrenia in rural China.

PubMed

Ran, Mao-Sheng; Chen, Sheying; Chen, Elaina Y; Ran, Bo-Yu; Tang, Cui-Ping; Lin, Fu-Rong; Li, Li; Li, Si-Gan; Mao, Wen-Jun; Hu, Shi-Hui

2011-11-01

The long-term work performance of persons with schizophrenia in the community is unclear. This study examined the status of long-term work functioning and the predictors of poor work status among patients with schizophrenia in a Chinese rural area. A 10-year follow-up investigation (1994-2004) of a cohort (n = 510) of persons with schizophrenia was conducted in Xinjin County, Chengdu, China. Compared with baseline data, work functioning of patients with schizophrenia deteriorated after 10 years. The rates of not working increased significantly from 12.0% in 1994 to 23.0% in 2004. Bivariate analyses showed that the poor work functioning in 2004 was significantly associated with male gender, older age, older age of first onset, higher level of education, longer duration of illness, lower family economic status, lack of caregivers, poor work status in 1994, living in shabby or unstable house, marked symptoms, and higher score on the Social Disability Screening Schedule (SDSS). In multiple logistic regression analyses, higher score of SDSS and poor work status in 1994 were identified as unique predictors of poor work status in 2004. The status of work functioning of persons with schizophrenia decreased over the course of the illness. The risk factors for poor work functioning and specific socio-cultural environment should be considered in planning community mental health services and rehabilitation for these patients.

Influence of Response Prepotency Strength, General Working Memory Resources, and Specific Working Memory Load on the Ability to Inhibit Predominant Responses: A Comparison of Young and Elderly Participants

ERIC Educational Resources Information Center

Grandjean, Julien; Collette, Fabienne

2011-01-01

One conception of inhibitory functioning suggests that the ability to successfully inhibit a predominant response depends mainly on the strength of that response, the general functioning of working memory processes, and the working memory demand of the task (Roberts, Hager, & Heron, 1994). The proposal that inhibition and functional working memory…

Work productivity is associated with disease activity and functional ability in Italian patients with early axial spondyloarthritis: an observational study from the SPACE cohort.

PubMed

de Hooge, Manouk; Ramonda, Roberta; Lorenzin, Mariagrazia; Frallonardo, Paola; Punzi, Leonardo; Ortolan, Augusta; Doria, Andrea

2016-11-16

Spondyloarthritis often affects young people, typically in their working years. The aim of our study was to investigate work productivity and its relationship with disease activity and physical functioning in Italian patients with axial spondyloarthritis (axSpA) with chronic back pain (CBP) for ≥3 months and ≤2 years, and onset  < 45 years of age. Baseline absenteeism, presenteeism, work productivity loss (assessed by the Work Productivity and Activity Impairment questionnaire (WPAI)), and disease activity (assessed by the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI)/Ankylosing Spondylitis Disease Activity Score (ASDAS)) and functional ability (assessed by the Bath Ankylosing Spondylitis Disease Functional Index (BASFI)) of patients with axSpA (rheumatologist's diagnosis) included in the Italian section of the Spondyloarthritis Caught Early (SPACE) cohort were collected. Multivariate linear regression analysis was used to evaluate the associations between work productivity and disease activity/physical functioning. Absenteeism in 51 patients with axSpA was low (8.3 %). A decrease in work productivity was related to an increase in disease activity. Disease activity was strongly correlated with absenteeism (p < 0.01), presenteeism (p < 0.01) and work productivity loss (p < 0.001). In addition, decreased work productivity was related to a decrease in functional ability. Physical functioning was correlated with absenteeism (p < 0.001), presenteeism (p < 0.05) and work productivity loss (p < 0.001). Impairment of work productivity was correlated with disease activity and physical functioning in Italian patients with axSpA with CBP for ≥3 months and ≤2 years, with onset <45 years of age.

Cognitive functioning, aging, and work: A review and recommendations for research and practice.

PubMed

Fisher, Gwenith G; Chaffee, Dorey S; Tetrick, Lois E; Davalos, Deana B; Potter, Guy G

2017-07-01

There is a larger proportion and number of older adults in the labor force than ever before. Furthermore, older adults in the workforce are working until later ages. Although a great deal of research has examined physical health and well-being of working older adults, less research has focused on cognitive functioning. The purpose of this article is to provide a broad contemporary and multidisciplinary review of the intersection between cognitive functioning, aging, and work as a follow-up to a paper previously written by Fisher et al. (2014). We begin by providing definitions and background about cognitive functioning and how it changes over the life span. Next we discuss theories relevant to the intersection of cognitive functioning and work, including the use-it-or-lose-it hypothesis, the cognitive reserve hypothesis, hypotheses regarding environmental influences on intellectual functioning, and the job-demands-resources model. Then we summarize recent research about the effects of work on cognitive functioning, as well as ways that cognitive functioning may influence work motivation, learning, development, training, and safety. We conclude by emphasizing the importance of person-environment fit, suggesting avenues for future research, and discussing practical implications for the field of occupational health psychology. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Role of point defects and HfO2/TiN interface stoichiometry on effective work function modulation in ultra-scaled complementary metal-oxide-semiconductor devices

NASA Astrophysics Data System (ADS)

Pandey, R. K.; Sathiyanarayanan, Rajesh; Kwon, Unoh; Narayanan, Vijay; Murali, K. V. R. M.

2013-07-01

We investigate the physical properties of a portion of the gate stack of an ultra-scaled complementary metal-oxide-semiconductor (CMOS) device. The effects of point defects, such as oxygen vacancy, oxygen, and aluminum interstitials at the HfO2/TiN interface, on the effective work function of TiN are explored using density functional theory. We compute the diffusion barriers of such point defects in the bulk TiN and across the HfO2/TiN interface. Diffusion of these point defects across the HfO2/TiN interface occurs during the device integration process. This results in variation of the effective work function and hence in the threshold voltage variation in the devices. Further, we simulate the effects of varying the HfO2/TiN interface stoichiometry on the effective work function modulation in these extremely-scaled CMOS devices. Our results show that the interface rich in nitrogen gives higher effective work function, whereas the interface rich in titanium gives lower effective work function, compared to a stoichiometric HfO2/TiN interface. This theoretical prediction is confirmed by the experiment, demonstrating over 700 meV modulation in the effective work function.

INTERPRETING PHYSICAL AND BEHAVIORAL HEALTH SCORES FROM NEW WORK DISABILITY INSTRUMENTS

PubMed Central

Marfeo, Elizabeth E.; Ni, Pengsheng; Chan, Leighton; Rasch, Elizabeth K.; McDonough, Christine M.; Brandt, Diane E.; Bogusz, Kara; Jette, Alan M.

2015-01-01

Objective To develop a system to guide interpretation of scores generated from 2 new instruments measuring work-related physical and behavioral health functioning (Work Disability – Physical Function (WD-PF) and WD – Behavioral Function (WD-BH)). Design Cross-sectional, secondary data from 3 independent samples to develop and validate the functional levels for physical and behavioral health functioning. Subjects Physical group: 999 general adult subjects, 1,017 disability applicants and 497 work-disabled subjects. Behavioral health group: 1,000 general adult subjects, 1,015 disability applicants and 476 work-disabled subjects. Methods Three-phase analytic approach including item mapping, a modified-Delphi technique, and known-groups validation analysis were used to develop and validate cut-points for functional levels within each of the WD-PF and WD-BH instrument’s scales. Results Four and 5 functional levels were developed for each of the scales in the WD-PF and WD-BH instruments. Distribution of the comparative samples was in the expected direction: the general adult samples consistently demonstrated scores at higher functional levels compared with the claimant and work-disabled samples. Conclusion Using an item-response theory-based methodology paired with a qualitative process appears to be a feasible and valid approach for translating the WD-BH and WD-PF scores into meaningful levels useful for interpreting a person’s work-related physical and behavioral health functioning. PMID:25729901

Level of functioning, perceived work ability, and work status among psychiatric patients with major mental disorders.

PubMed

Karpov, B; Joffe, G; Aaltonen, K; Suvisaari, J; Baryshnikov, I; Näätänen, P; Koivisto, M; Melartin, T; Oksanen, J; Suominen, K; Heikkinen, M; Isometsä, E

2017-07-01

Major mental disorders are highly disabling conditions that result in substantial socioeconomic burden. Subjective and objective measures of functioning or ability to work, their concordance, or risk factors for them may differ between disorders. Self-reported level of functioning, perceived work ability, and current work status were evaluated among psychiatric care patients with schizophrenia or schizoaffective disorder (SSA, n=113), bipolar disorder (BD, n=99), or depressive disorder (DD, n=188) within the Helsinki University Psychiatric Consortium Study. Correlates of functional impairment, subjective work disability, and occupational status were investigated using regression analysis. DD patients reported the highest and SSA patients the lowest perceived functional impairment. Depressive symptoms in all diagnostic groups and anxiety in SSA and BD groups were significantly associated with disability. Only 5.3% of SSA patients versus 29.3% or 33.0% of BD or DD patients, respectively, were currently working. About half of all patients reported subjective work disability. Objective work status and perceived disability correlated strongly among BD and DD patients, but not among SSA patients. Work status was associated with number of hospitalizations, and perceived work disability with current depressive symptoms. Psychiatric care patients commonly end up outside the labour force. However, while among patients with mood disorders objective and subjective indicators of ability to work are largely concordant, among those with schizophrenia or schizoaffective disorder they are commonly contradictory. Among all groups, perceived functional impairment and work disability are coloured by current depressive symptoms, but objective work status reflects illness course, particularly preceding psychiatric hospitalizations. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

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

PubMed Central

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

Effects of marital status and shift work on family function among registered nurses.

PubMed

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.

Performance investigation of bandgap, gate material work function and gate dielectric engineered TFET with device reliability improvement

NASA Astrophysics Data System (ADS)

Raad, Bhagwan Ram; Nigam, Kaushal; Sharma, Dheeraj; Kondekar, P. N.

2016-06-01

This script features a study of bandgap, gate material work function and gate dielectric engineering for enhancement of DC and Analog/RF performance, reduction in the hot carriers effect (HCEs) and drain induced barrier lowering (DIBL) for better device reliability. In this concern, the use of band gap and gate material work function engineering improves the device performance in terms of the ON-state current and suppressed ambipolar behaviour with maintaining the low OFF-state current. With these advantages, the use of gate material work function engineering imposes restriction on the high frequency performance due to increment in the parasitic capacitances and also introduces the hot carrier effects. Hence, the gate dielectric engineering with bandgap and gate material work function engineering are used in this paper to overcome the cons of the gate material work function engineering by obtaining a superior performance in terms of the current driving capability, ambipolar conduction, HCEs, DIBL and high frequency parameters of the device for ultra-low power applications. Finally, the optimization of length for different work function is performed to get the best out of this.

The impact of depression and diabetes mellitus on older workers' functioning.

PubMed

Stynen, D; Jansen, N W H; Kant, I J

2015-12-01

Using the International Classification of Functioning, Disability and Health as a framework, this study investigates the impact of depression and diabetes mellitus on older workers' functioning (problems with concentration, physical functioning, need for recovery and work and social participation restrictions). The study focuses on how these chronic conditions, in their interaction with the work context, affect older workers' functioning, which may be an important precursor of early retirement. Older workers (≥ 45years) with depression (n=127) or diabetes mellitus (n=107) enrolled in the prospective Maastricht Cohort Study (MCS) were followed between October 2008 and October 2012. Linear, logistic and Cox regression analyses were performed to investigate the effect of these health conditions on workers' functioning compared to a reference group of older workers without a chronic condition (n=1612). The interaction with participants' working conditions (psychological job demands, decision latitude and strenuous work) was also analysed. Compared to the reference group, depression and diabetes mellitus were (over time) positively related with need for recovery caseness and restrictions in social participation but not with restrictions in work participation. Depression was positively related with concentration problems and need for recovery, whereas diabetes mellitus was negatively related with physical functioning. Finally, the relationship between functioning and depression and diabetes mellitus depends on working conditions. Older workers with depression or diabetes mellitus are vulnerable to losses in specific domains of functioning. The impact on functioning varies across working conditions, providing insight for disease-tailored preventive measures. Copyright © 2015 Elsevier Inc. All rights reserved.

Low work function silicon collector for thermionic converters

NASA Technical Reports Server (NTRS)

Chang, K. H.; Shimada, K.

1976-01-01

To improve the efficiency of present thermionic converters, single crystal silicon was investigated as a low work function collector material. The experiments were conducted in a test vehicle which resembled an actual thermionic converter. Work function as low as 1.0eV was obtained with an n-type silicon. The stabilities of the activated surfaces at elevated temperatures were tested by raising the collector temperature up to 829 K. By increasing the Cs arrival rate, it was possible to restore the originally activated low work function of the surface at elevated surface temperatures. These results, plotted in the form of Rasor-Warner curve, show a behavior similar to that of metal electrode except that the minimum work function was much lower with silicon than with metals.

Associations of SF-36 mental health functioning and work and family related factors with intentions to retire early among employees.

PubMed

Harkonmäki, K; Rahkonen, O; Martikainen, P; Silventoinen, K; Lahelma, E

2006-08-01

To examine the associations of mental health functioning (SF-36) and work and family related psychosocial factors with intentions to retire early. Cross sectional survey data (n = 5037) from the Helsinki Health Study occupational cohort in 2001 and 2002 were used. Intentions to retire early were inquired with a question: "Have you considered retiring before normal retirement age?" Mental health functioning was measured by the Short Form 36 (SF-36) mental component summary (MCS). Work and family related psychosocial factors included job demands and job control, procedural and relational justice, conflicts between work and family, and social network size. Multinomial regression models were used to analyse the data. Poor mental health functioning, unfavourable psychosocial working conditions, and conflicts between work and family were individually related to intentions to retire early. After adjustments for all work and family related factors the odds ratio for low mental health functioning was halved (from OR = 6.05 to 3.67), but nevertheless the association between poor mental health functioning and strong intentions to retire early remained strong. These findings highlight not only the importance of low mental health and unfavourable working conditions but also the simultaneous impact of conflicts between work and family to employees' intentions to retire early.

Work function measurements during plasma exposition at conditions relevant in negative ion sources for the ITER neutral beam injection.

PubMed

Gutser, R; Wimmer, C; Fantz, U

2011-02-01

Cesium seeded sources for surface generated negative hydrogen ions are major components of neutral beam injection systems in future large-scale fusion experiments such as ITER. The stability and delivered current density depend highly on the work function during vacuum and plasma phases of the ion source. One of the most important quantities that affect the source performance is the work function. A modified photocurrent method was developed to measure the temporal behavior of the work function during and after cesium evaporation. The investigation of cesium exposed Mo and MoLa samples under ITER negative hydrogen ion based neutral beam injection relevant surface and plasma conditions showed the influence of impurities which result in a fast degradation when the plasma exposure or the cesium flux onto the sample is stopped. A minimum work function close to that of bulk cesium was obtained under the influence of the plasma exposition, while a significantly higher work function was observed under ITER-like vacuum conditions.

Generation of low work function, stable compound thin films by laser ablation

DOEpatents

Dinh, Long N.; McLean, II, William; Balooch, Mehdi; Fehring, Jr., Edward J.; Schildbach, Marcus A.

2001-01-01

Generation of low work function, stable compound thin films by laser ablation. Compound thin films with low work function can be synthesized by simultaneously laser ablating silicon, for example, and thermal evaporating an alkali metal into an oxygen environment. For example, the compound thin film may be composed of Si/Cs/O. The work functions of the thin films can be varied by changing the silicon/alkali metal/oxygen ratio. Low work functions of the compound thin films deposited on silicon substrates were confirmed by ultraviolet photoelectron spectroscopy (UPS). The compound thin films are stable up to 500.degree. C. as measured by x-ray photoelectron spectroscopy (XPS). Tests have established that for certain chemical compositions and annealing temperatures of the compound thin films, negative electron affinity (NEA) was detected. The low work function, stable compound thin films can be utilized in solar cells, field emission flat panel displays, electron guns, and cold cathode electron guns.

Psychological distress as a mediator of the association between disease severity and occupational functioning among employed spouses of women recently diagnosed with breast cancer.

PubMed

Manne, Sharon L; Siegel, Scott; Heckman, Carolyn J; Kashy, Deborah A

2015-11-01

The purpose was to evaluate whether patient and spouse cancer-specific distress mediated the association between cancer severity and occupational functioning among employed spouses of women diagnosed with breast cancer. We examined whether sociodemographic characteristics, lower spouse-reported marital quality, and lower spouse self-rated health were associated with poorer spouse occupational functioning. One hundred forty-three currently employed spouses of women diagnosed with breast cancer were administered measures of socioeconomic status, occupational functioning (work absenteeism, low productivity, and poor performance), cancer-specific distress, marital quality, and self-rated health. Patients completed measures of cancer-related distress and functional impairment and cancer stage were collected from medical charts. In the model evaluating work absenteeism, greater patient functional impairment was associated with more absenteeism, but there was no evidence of a mediating effect for either partners' cancer-specific distress. Higher cancer stage and more functional impairment were associated with higher spouse cancer-specific distress, which in turn predicted poorer work productivity. Patient cancer-specific distress did not mediate the association between patient functional impairment or cancer stage and spouse work productivity. Finally, higher cancer stage was associated with more spouse cancer-specific distress, which in turn predicted poorer work performance. There were no direct or indirect effects of the patient's functional impairment on spouse work performance. Distressed spouses are more likely to have poorer work productivity after their partners' breast cancer diagnosis. These spouses may need assistance in managing their distress and the patient's functional impairment to ensure that their work productivity is not adversely affected. Copyright © 2015 John Wiley & Sons, Ltd.

Addressing defeatist beliefs in work rehabilitation

PubMed Central

Mervis, Joshua E.; Lysaker, Paul H.; Fiszdon, Joanna M.; Bell, Morris D.; Chue, Amanda E.; Pauls, Carol; Bisoglio, Joseph; Choi, Jimmy

2018-01-01

Background Adults with serious mental illness (SMI) may struggle with expectations of failure in vocational rehabilitation. These expectations can be global and trait-like or performance-specific and related to ability. Aims To date, it has not been examined whether global or performance-specific defeatist beliefs are related to functional outcomes. Method The Indianapolis Vocational Intervention Program (IVIP) is a CBT intervention used to address expectations of failure and improve work performance. We examined the relationships between defeatist beliefs, self-esteem, social functioning, and work behaviors in 54 adults with SMI who completed IVIP within a work therapy program. Results Baseline work-specific defeatist beliefs were related to baseline self-esteem, employment attitude, and work behaviors. Decline in work-specific defeatist beliefs was associated with better social functioning, self-esteem, and work behaviors. Decline in global defeatist beliefs was only associated with improvements in social functioning. Conclusions Performance-specific expectations about work may be an appropriate therapeutic target to enhance work outcome in SMI. PMID:26828824

Subjective cognitive complaints, psychosocial factors and nursing work function in nurses providing direct patient care.

PubMed

Barbe, Tammy; Kimble, Laura P; Rubenstein, Cynthia

2018-04-01

The aim of this study was to examine relationships among subjective cognitive complaints, psychosocial factors and nursing work function in nurses providing direct patient care. Cognitive functioning is a critical component for nurses in the assurance of error prevention, identification and correction when caring for patients. Negative changes in nurses' cognitive and psychosocial functioning can adversely affect nursing care and patient outcomes. A descriptive correlational design with stratified random sampling. The sample included 96 nurses from the major geographic regions of the United States. Over 9 months in 2016-2017, data were collected using a web-based survey. Stepwise multiple linear regression analyses were used to examine relationships among subjective cognitive complaints, psychosocial factors and nursing work function. Overall, participants reported minimal work function impairment and low levels of subjective cognitive complaints, depression and stress. In multivariate analyses, depression was not associated with nurses' work function. However, perceived stress and subjective concerns about cognitive function were associated with greater impairment of work function. Nurses experiencing subjective cognitive complaints should be encouraged to address personal and environmental factors that are associated with their cognitive status. Additionally, stress reduction in nurses should be a high priority as a potential intervention to promote optimal functioning of nurses providing direct patient care. Healthcare institutions should integrate individual and institutional strategies to reduce factors contributing to workplace stress. © 2017 John Wiley & Sons Ltd.

The impact of fatigue and energy on work functioning and impairment in patients with major depressive disorder treated with desvenlafaxine.

PubMed

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.

The local work function: Concept and implications

NASA Astrophysics Data System (ADS)

Wandelt, K.

1997-02-01

The term 'local work function' is now widely applied. The present work discusses the common physical basis of 'photoemission of adsorbed xenon (PAX)' and 'two-photon photonemissionspectroscopy of image potential states' as local work function probes. New examples with bimetallic and defective surfaces are presented which demonstrate the capability of PAX measurements for the characterization of heterogeneous surfaces on an atomic scale. Finally, implications of the existence of short-range variations of the surface potential at surface steps are addressed. In particular, dynamical work function change measurements are a sensitive probe for the step-density at surfaces and, as such, a powerful in-situ method to monitor film growth.

Work function tunability of borophene via doping: A first principle study

NASA Astrophysics Data System (ADS)

Katoch, Neha; Sharma, Munish; Thakur, Rajesh; Ahluwalia, P. K.

2018-04-01

A first principle study of structural properties, work function and electronic properties of pristine and substitutional doped borophene atomic layer with X atoms (X = F, Cl, H, Li, Na) have been carried out within the framework of density functional theory (DFT). Studied adsorption energies are high for all dopants indicating adsorption to be chemisorption type. The reduction in work function of pristine borophene has been found with n-type (Li, Na) dopants is of the order of 0.42 eV which is higher than that of the reduction in work function of borophene with p-type (F, Cl) dopants. For H dopants there is no reduction in work function of borophene. Quantum ballistic conductance has been found to modulate with doping. The quantum ballistic conductance is decreasing for doped borophene in the order Li > Cl ˜ H ˜ Na > F as compared to pristine borophene.

Long-term health and work outcomes of renal transplantation and patterns of work status during the end-stage renal disease trajectory.

PubMed

van der Mei, Sijrike F; Kuiper, Daphne; Groothoff, Johan W; van den Heuvel, Wim J A; van Son, Willem J; Brouwer, Sandra

2011-09-01

The aim of this study was to examine the health- and work outcomes of renal transplant recipients long-term after transplantation as well as the pattern of work status, work ability and disability benefits during the end-stage renal disease (ESRD) trajectory that precedes transplantation. 34 transplant recipients completed interviews 3, 13 months and >6 years posttransplantation. Health status (SF-36), work ability (WAI), and fatigue (CIS) were assessed by questionnaires, clinical data were derived from medical charts, and data on functional limitations were extracted from the social security system database. The work status trajectory preceding transplantation was examined retrospectively. Of the 34 third wave transplant recipients, 29% were severely fatigued. Compared with the general working population, recipients experienced worse general health and less vitality. Non-working recipients had worse renal function and general health, and more limitations in physical functioning compared to working recipients. The WAI score indicated moderate work ability for 60% of the employed recipients. Although 67% were employed (45% parttime), 30% of those working still received some disability benefits. Social insurance physicians found variable levels of functional limitations. The mean work status trajectory showed more sickness absence and less work ability during dialysis, but after transplantation, both work status and work ability generally improved. Transplant recipients have a compromised health status which leads to functional limitations and disability. Although work status improved after transplantation, a substantial number of the transplant recipients received disability benefits. The negative health consequences of anti-rejection medications may play an important role in long-term work ability. These results indicate that a 'new' kidney has advantages over dialysis with respect to work, but does not necessarily leads to 'normal' work outcomes.

Evidence for a Role of Executive Functions in Learning Biology

ERIC Educational Resources Information Center

Rhodes, Sinéad M.; Booth, Josephine N.; Campbell, Lorna Elise; Blythe, Richard A.; Wheate, Nial J.; Delibegovic, Mirela

2014-01-01

Research examining cognition and science learning has focused on working memory, but evidence implicates a broader set of executive functions. The current study examined executive functions and learning of biology in young adolescents. Fifty-six participants, aged 12-13?years, completed tasks of working memory (Spatial Working Memory), inhibition…

Functional Imaging of Working Memory and Peripheral Endothelial Function in Middle-Aged Adults

ERIC Educational Resources Information Center

Gonzales, Mitzi M.; Tarumi, Takashi; Tanaka, Hirofumi; Sugawara, Jun; Swann-Sternberg, Tali; Goudarzi, Katayoon; Haley, Andreana P.

2010-01-01

The current study examined the relationship between a prognostic indicator of vascular health, flow-mediated dilation (FMD), and working memory-related brain activation in healthy middle-aged adults. Forty-two participants underwent functional magnetic resonance imaging while completing a 2-Back working memory task. Brachial artery…

Engineering Ultra-Low Work Function of Graphene.

PubMed

Yuan, Hongyuan; Chang, Shuai; Bargatin, Igor; Wang, Ning C; Riley, Daniel C; Wang, Haotian; Schwede, Jared W; Provine, J; Pop, Eric; Shen, Zhi-Xun; Pianetta, Piero A; Melosh, Nicholas A; Howe, Roger T

2015-10-14

Low work function materials are critical for energy conversion and electron emission applications. Here, we demonstrate for the first time that an ultralow work function graphene is achieved by combining electrostatic gating with a Cs/O surface coating. A simple device is built from large-area monolayer graphene grown by chemical vapor deposition, transferred onto 20 nm HfO2 on Si, enabling high electric fields capacitive charge accumulation in the graphene. We first observed over 0.7 eV work function change due to electrostatic gating as measured by scanning Kelvin probe force microscopy and confirmed by conductivity measurements. The deposition of Cs/O further reduced the work function, as measured by photoemission in an ultrahigh vacuum environment, which reaches nearly 1 eV, the lowest reported to date for a conductive, nondiamond material.

Theoretical studies of the work functions of Pd-based bimetallic surfaces

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

Ding, Zhao-Bin; Wu, Feng; Wang, Yue-Chao

2015-06-07

Work functions of Pd-based bimetallic surfaces, including mainly M/Pd(111), Pd/M, and Pd/M/Pd(111) (M = 4d transition metals, Cu, Au, and Pt), are studied using density functional theory. We find that the work function of these bimetallic surfaces is significantly different from that of parent metals. Careful analysis based on Bader charges and electron density difference indicates that the variation of the work function in bimetallic surfaces can be mainly attributed to two factors: (1) charge transfer between the two different metals as a result of their different intrinsic electronegativity, and (2) the charge redistribution induced by chemical bonding between themore » top two layers. The first factor can be related to the contact potential, i.e., the work function difference between two metals in direct contact, and the second factor can be well characterized by the change in the charge spilling out into vacuum. We also find that the variation in the work functions of Pd/M/Pd(111) surfaces correlates very well with the variation of the d-band center of the surface Pd atom. The findings in this work can be used to provide general guidelines to design new bimetallic surfaces with desired electronic properties.« less

Thermal stability of atomic layer deposited WCxNy electrodes for metal oxide semiconductor devices

NASA Astrophysics Data System (ADS)

Zonensain, Oren; Fadida, Sivan; Fisher, Ilanit; Gao, Juwen; Danek, Michal; Eizenberg, Moshe

2018-01-01

This study is a thorough investigation of the chemical, structural, and electrical stability of W based organo-metallic films, grown by atomic layer deposition, for future use as gate electrodes in advanced metal oxide semiconductor structures. In an earlier work, we have shown that high effective work-function (4.7 eV) was produced by nitrogen enriched films (WCxNy) dominated by W-N chemical bonding, and low effective work-function (4.2 eV) was produced by hydrogen plasma resulting in WCx films dominated by W-C chemical bonding. In the current work, we observe, using x-ray diffraction analysis, phase transformation of the tungsten carbide and tungsten nitride phases after 900 °C annealing to the cubic tungsten phase. Nitrogen diffusion is also observed and is analyzed with time-of-flight secondary ion mass spectroscopy. After this 900 °C anneal, WCxNy effective work function tunability is lost and effective work-function values of 4.7-4.8 eV are measured, similar to stable effective work function values measured for PVD TiN up to 900 °C anneal. All the observed changes after annealing are discussed and correlated to the observed change in the effective work function.

Socioeconomic inequalities in physical and mental functioning of British, Finnish, and Japanese civil servants: role of job demand, control, and work hours.

PubMed

Sekine, Michikazu; Chandola, Tarani; Martikainen, Pekka; Marmot, Michael; Kagamimori, Sadanobu

2009-11-01

This study aims to evaluate whether the pattern of socioeconomic inequalities in physical and mental functioning as measured by the Short Form 36 (SF-36) differs among employees in Britain, Finland, and Japan and whether work characteristics contribute to some of the health inequalities. The participants were 7340 (5122 men and 2218 women) British employees, 2297 (1638 men and 659 women) Japanese employees, and 8164 (1649 men and 6515 women) Finnish employees. All the participants were civil servants aged 40-60 years. Both male and female low grade employees had poor physical functioning in all cohorts. British and Japanese male low grade employees tended to have poor mental functioning but the associations were significant only for Japanese men. No consistent employment-grade differences in mental functioning were observed among British and Japanese women. Among Finnish men and women, high grade employees had poor mental functioning. In all cohorts, high grade employees had high control, high demands and long work hours. The grade differences in poor physical functioning and disadvantaged work characteristics among non-manual workers were somewhat smaller in the Finnish cohort than in the British and Japanese cohorts. Low control, high demands, and both short and long work hours were associated with poor functioning. When work characteristics were adjusted for, the socioeconomic differences in poor functioning were mildly attenuated in men, but the differences increased slightly in women. This study reconfirms the generally observed pattern of socioeconomic inequalities in health for physical functioning but not for mental functioning. The role of work characteristics in the relationship between socioeconomic status and health differed between men and women but was modest overall. We suggest that these differences in the pattern and magnitude of grade differences in work characteristics and health among the 3 cohorts may be attributable to the different welfare regimes among the 3 countries.

Socioeconomic Inequalities in Physical and Mental Functioning of British, Finnish, and Japanese Civil Servants: Role of Job Demand, Control, and Work Hours

PubMed Central

Chandola, Tarani; Martikainen, Pekka; Marmot, Michael; Kagamimori, Sadanobu

2009-01-01

This study aims to evaluate whether the pattern of socioeconomic inequalities in physical and mental functioning as measured by the Short Form 36 (SF-36) differs among employees in Britain, Finland, and Japan and whether work characteristics contribute to some of the health inequalities. The participants were 7340 (5122 men and 2218 women) British employees, 2297 (1638 men and 659 women) Japanese employees, and 8164 (1649 men and 6515 women) Finnish employees. All the participants were civil servants aged 40–60 years. Both male and female low grade employees had poor physical functioning in all cohorts. British and Japanese male low grade employees tended to have poor mental functioning but the associations were significant only for Japanese men. No consistent employment-grade differences in mental functioning were observed among British and Japanese women. Among Finnish men and women, high grade employees had poor mental functioning. In all cohorts, high grade employees had high control, high demands and long work hours. The grade differences in poor physical functioning and disadvantaged work characteristics among non-manual workers were somewhat smaller in the Finnish cohort than in the British and Japanese cohorts. Low control, high demands, and both short and long work hours were associated with poor functioning. When work characteristics were adjusted for, the socioeconomic differences in poor functioning were mildly attenuated in men, but the differences increased slightly in women. This study reconfirms the generally observed pattern of socioeconomic inequalities in health for physical functioning but not for mental functioning. The role of work characteristics in the relationship between socioeconomic status and health differed between men and women but was modest overall. We suggest that these differences in the pattern and magnitude of grade differences in work characteristics and health among the 3 cohorts may be attributable to the different welfare regimes among the 3 countries. PMID:19767137

A 20-Year multi-followup longitudinal study assessing whether antipsychotic medications contribute to work functioning in schizophrenia.

PubMed

Harrow, Martin; Jobe, Thomas H; Faull, Robert N; Yang, Jie

2017-10-01

To assess the long-term effectiveness of antipsychotic medications in facilitating work functioning in patients with schizophrenia we conducted longitudinal multifollowup research on 139 initially psychotic patients. The 70 patients with schizophrenia and 69 initially psychotic mood disordered control patients were followed up 6 times over 20 years. We compared the influence on work functioning of patients with schizophrenia continuously prescribed antipsychotics with patients with schizophrenia not prescribed antipsychotics, using statistical controls for inter-subject differences. While antipsychotics reduce or eliminate flagrant psychosis for most patients with schizophrenia at acute hospitalizations, four years later and continually until the 20 year followups, patients with schizophrenia not prescribed antipsychotics had significantly better work functioning. The work performance of the patients who were continuously prescribed antipsychotics was at a low rate and did not improve over time. Multiple other factors also interfere with work functioning. The data suggest that some patients with schizophrenia not prescribed antipsychotics for prolonged periods can function relatively well. Multiple other factors are associated with poor post-hospital work performance. The longitudinal data raise questions about prolonged treatment of schizophrenia with antipsychotic medications. Copyright © 2017 Elsevier B.V. All rights reserved.

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

NASA Astrophysics Data System (ADS)

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.

`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

PubMed Central

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 `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. PMID:25642103

`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.

PubMed

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.

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

PubMed

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.

Functional measures developed for clinical populations identified impairment among active workers with upper extremity disorders

PubMed Central

Gardner, Bethany T.; Dale, Ann Marie; Buckner-Petty, Skye; Rachford, Robert; Strickland, Jaime; Kaskutas, Vicki; Evanoff, Bradley

2017-01-01

Purpose Few studies have explored measures of function across a range of health outcomes in a general working population. Using four upper extremity (UE) case definitions from the scientific literature, we described the performance of functional measures of work, activities of daily living, and overall health. Methods A sample of 573 workers completed several functional measures: modified recall versions of the QuickDASH, Levine Functional Status Scale (FSS), DASH Work module (DASH-W), and standard SF-8 physical component score. We determined case status based on four UE case definitions: 1) UE symptoms, 2) UE musculoskeletal disorders (MSD), 3) carpal tunnel syndrome (CTS), and 4) work limitations due to UE symptoms. We calculated effect sizes for each case definition to show the magnitude of the differences that were detected between cases and non-cases for each case definition on each functional measure. Sensitivity and specificity analyses showed how well each measure identified functional impairments across the UE case definitions. Results All measures discriminated between cases and non-cases for each case definition with the largest effect sizes for CTS and work limitations, particularly for the modified FSS and DASH-W measures. Specificity was high and sensitivity was low for outcomes of UE symptoms and UE MSD in all measures. Sensitivity was high for CTS and work limitations. Conclusions Functional measures developed specifically for use in clinical, treatment-seeking populations may identify mild levels of impairment in relatively healthy, active working populations, but measures performed better among workers with CTS or those reporting limitations at work. PMID:26091980

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

PubMed

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.

Improving work functioning and mental health of health care employees using an e-mental health approach to workers' health surveillance: pretest-posttest study.

PubMed

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 < 0.01). 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.

20 CFR 220.126 - Relationship of ability to do work and residual functional capacity.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 20 Employees' Benefits 1 2014-04-01 2012-04-01 true Relationship of ability to do work and... Relationship of ability to do work and residual functional capacity. (a) If the claimant can do his or her previous work (his or her usual work or other applicable past work), the Board will determine he or she is...

20 CFR 220.126 - Relationship of ability to do work and residual functional capacity.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 20 Employees' Benefits 1 2012-04-01 2012-04-01 false Relationship of ability to do work and... Relationship of ability to do work and residual functional capacity. (a) If the claimant can do his or her previous work (his or her usual work or other applicable past work), the Board will determine he or she is...

20 CFR 220.126 - Relationship of ability to do work and residual functional capacity.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 20 Employees' Benefits 1 2013-04-01 2012-04-01 true Relationship of ability to do work and... Relationship of ability to do work and residual functional capacity. (a) If the claimant can do his or her previous work (his or her usual work or other applicable past work), the Board will determine he or she is...

20 CFR 220.126 - Relationship of ability to do work and residual functional capacity.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 20 Employees' Benefits 1 2010-04-01 2010-04-01 false Relationship of ability to do work and... Relationship of ability to do work and residual functional capacity. (a) If the claimant can do his or her previous work (his or her usual work or other applicable past work), the Board will determine he or she is...

Vitality at work and its associations with lifestyle, self-determination, organizational culture, and with employees' performance and sustainable employability.

PubMed

van Scheppingen, Arjella R; de Vroome, Ernest M M; Ten Have, Kristin C J M; Zwetsloot, Gerard I J M; Wiezer, Noortje; van Mechelen, Willem

2015-01-01

Vitality at work is an important factor for optimal functioning and sustainable employability. To date, knowledge on how to promote vitality at work is fragmented. Contribute to knowledge on how to promote vitality at work. Determinants of vitality at work are identified from three scientific fields, and used in a comprehensive model. Regression analyses on cross-sectional data from a Dutch dairy company (N= 629) are performed to examine the associations between these factors, vitality at work, and employees' perceived effective personal functioning and sustainable employability. Vitality at work is most strongly associated with basic psychological needs of self-determination, but also with healthy lifestyle behavior, having a balanced workstyle, and social capital. Vitality at work is also associated with effective personal functioning and with sustainable employability. The study confirms the multifactorial nature of vitality at work. Since organizational culture may support self-determination, and cultural aspects themselves are positively associated with vitality, organizational culture seems particular important in promoting vitality at work. Additionally, a healthy lifestyle appears important. The associations between vitality at work and effective personal functioning and sustainable employability endorse the combined health-based, business-related and societal importance of vitality at work.

Intermediate connector for stacked organic light emitting devices

DOEpatents

D& #x27; Andrade, Brian

2013-02-12

A device is provided, having an anode, a cathode, and an intermediate connector disposed between the anode and the cathode. A first organic layer including an emissive sublayer is disposed between the anode and the intermediate connector, and a second including an emissive sublayer is disposed between the intermediate connector and the cathode. The intermediate connector includes a first metal having a work function lower than 4.0 eV and a second metal having a work function lower than 5.0 eV. The work function of the first metal is at least 0.5 eV less than the work function of the second metal. The first metal is in contact with a sublayer of the second organic layer that includes a material well adapted to receive holes from a low work function metal.

Prospective memory, level of disability, and return to work in severe mental illness.

PubMed

Burton, Cynthia Z; Vella, Lea; Twamley, Elizabeth W

2018-02-25

Prospective memory (the ability to remember to do things) has clear implications for everyday functioning, including employment, in people with severe mental illnesses (SMI). This study aimed to evaluate prospective memory performance and its relationship to real-world functional variables in an employment-seeking sample of people with SMI (Clinical Trial registration number NCT00895258). 153 individuals with DSM-IV diagnosis of depression (n = 58), bipolar disorder (n = 37), or schizophrenia (n = 58) who were receiving outpatient psychiatric care at a university clinic enrolled in a trial of supported employment and completed a baseline assessment. Prospective memory was measured with the Memory for Intentions Test (MIST); real-world functional status included work history variables, clinical history variables, baseline functional capacity (UCSD Performance-based Skills Assessment-Brief), and work outcomes (weeks worked and wages earned during two years of supported employment). Participants with schizophrenia performed worse on the MIST than did those with affective disorders. Independent of diagnosis, education, and estimated intellectual functioning, prospective memory significantly predicted variance in measures of disability and illness burden (disability benefits, hospitalization history, current functional capacity), and work outcomes over two years of supported employment (weeks worked). Worse prospective memory appears to be associated with greater illness burden and functional disability in SMI. Mental health clinicians and employment specialists may counsel clients to use compensatory prospective memory strategies to improve work performance and decrease functional disability associated with SMI.

Working Memory in Children With Neurocognitive Effects From Sickle Cell Disease: Contributions of the Central Executive and Processing Speed

PubMed Central

Smith, Kelsey E.; Schatz, Jeffrey

2017-01-01

Children with sickle cell disease (SCD) are at risk for working memory deficits due to multiple disease processes. We assessed working memory abilities and related functions in 32 school-age children with SCD and 85 matched comparison children using Baddeley’s working memory model as a framework. Children with SCD performed worse than controls for working memory, central executive function, and processing/rehearsal speed. Central executive function was found to mediate the relationship between SCD status and working memory, but processing speed did not. Cognitive remediation strategies that focus on central executive processes may be important for remediating working memory deficits in SCD. PMID:27759435

The work role functioning questionnaire 2.0 (Dutch version): examination of its reliability, validity and responsiveness in the general working population.

PubMed

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

2013-03-01

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 workers with health problems. The aim of this study is to evaluate the reliability, validity (including five new items) and responsiveness of the WRFQ 2.0 in the working population. A longitudinal study was conducted among workers. The reliability (internal consistency, test-retest reliability, measurement error), validity (structural validity-factor analysis, construct validity by means of hypotheses testing) and responsiveness of the WRFQ 2.0 were evaluated. A total of N = 553 workers completed the survey. The final WRFQ 2.0 has four subscales and showed very good internal consistency, moderate test-retest reliability, good construct validity and moderate responsiveness in the working population. The WRFQ was able to distinguish between groups with different levels of mental health, physical health, fatigue and need for recovery. A moderate correlation was found between WRFQ and related constructs respectively work ability and work productivity. A weak relationship was found with general self-rated health, work engagement and work involvement. The WRFQ 2.0 is a reliable and valid instrument to measure health-related work functioning in the working population. Further validation in larger samples is recommended, especially for test-retest reliability, responsiveness and the questionnaire's ability to predict the future course of health-related work functioning.

Work Outcomes in Patients Who Stay at Work Despite Musculoskeletal Pain.

PubMed

Cochrane, Andy; Higgins, Niamh M; Rothwell, Conor; Ashton, Jennifer; Breen, Roisin; Corcoran, Oriel; FitzGerald, Oliver; Gallagher, Pamela; Desmond, Deirdre

2017-12-13

Purpose To assess self-reported work impacts and associations between psychosocial risk factors and work impairment amongst workers seeking care for musculoskeletal pain while continuing to work. Methods Patients were recruited from Musculoskeletal Assessment Clinics at 5 hospitals across Ireland. Participants completed questionnaires including assessments of work impairment (Work Productivity and Activity Impairment Questionnaire), work ability (single item from the Work Ability Index) and work performance (Work Role Functioning Questionnaire; WRFQ). Logistic and hierarchical regressions were conducted to analyse the relation between psychosocial variables and work outcomes. Results 155 participants (53.5% female; mean age = 46.50 years) who were working at the time of assessment completed the questionnaires. Absenteeism was low, yet 62.6% were classified as functioning poorly according to the WRFQ; 52.3% reported having poor work ability. Logistic regression analyses indicated that higher work role functioning was associated with higher pain self-efficacy (OR 1.51); better work ability was associated with older age (OR 1.063) and lower functional restriction (OR 0.93); greater absenteeism was associated with lower pain self-efficacy (OR 0.65) and poorer work expectancy (OR 1.18). Multiple regression analysis indicated that greater presenteeism was associated with higher pain intensity (β = 0.259) and lower pain self-efficacy (β = - 0.385). Conclusions While individuals continue to work with musculoskeletal pain, their work performance can be adversely affected. Interventions that target mutable factors, such as pain self-efficacy, may help reduce the likelihood of work impairment.

Long-term symptomatic, functional, and work outcomes of carpal tunnel syndrome among construction workers.

PubMed

Evanoff, Bradley; Gardner, Bethany T; Strickland, Jaime R; Buckner-Petty, Skye; Franzblau, Alfred; Dale, Ann Marie

2016-05-01

The long-term outcomes of carpal tunnel syndrome (CTS) including symptoms, functional status, work disability, and economic impact are unknown. We conducted a retrospective study of 234 active construction workers with medical claims for CTS and 249 workers without CTS claims; non-cases were matched on age, trade, and insurance eligibility. We conducted telephone interviews with cases and non-cases and collected administrative data on work hours. Compared to non-cases, CTS cases were more likely to report recurrent hand symptoms, decreased work productivity/quality, decreased performance of physical work demands, and greater functional limitations. Surgical cases showed larger improvements on multiple outcomes than non-surgical cases. Minimal differences in paid work hours were seen between cases and non-cases in the years preceding and following CTS claims. Persistent symptoms and functional impairments were present several years after CTS diagnosis. Long-term functional limitations shown by this and other studies indicate the need for improved prevention and treatment. © 2016 Wiley Periodicals, Inc.

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

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

Meyer, Dominik; Schäfer, Tobias; Schulz, Philip

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 functionmore » 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.« less

The role of high work-function metallic nanodots on the performance of a-Si:H solar cells: offering ohmic contact to light trapping.

PubMed

Kim, Jeehwan; Abou-Kandil, Ahmed; Fogel, Keith; Hovel, Harold; Sadana, Devendra K

2010-12-28

Addition of carbon into p-type "window" layers in hydrogenated amorphous silicon (a-Si:H) solar cells enhances short circuit currents and open circuit voltages by a great deal. However, a-Si:H solar cells with high carbon-doped "window" layers exhibit poor fill factors due to a Schottky barrier-like impedance at the interface between a-SiC:H windows and transparent conducting oxides (TCO), although they show maximized short circuit currents and open circuit voltages. The impedance is caused by an increasing mismatch between the work function of TCO and that of p-type a-SiC:H. Applying ultrathin high-work-function metals at the interface between the two materials results in an effective lowering of the work function mismatch and a consequent ohmic behavior. If the metal layer is sufficiently thin, then it forms nanodots rather than a continuous layer which provides light-scattering effect. We demonstrate 31% efficiency enhancement by using high-work-function materials for engineering the work function at the key interfaces to raise fill factors as well as photocurrents. The use of metallic interface layers in this work is a clear contrast to previous work where attempts were made to enhance the photocurrent using plasmonic metal nanodots on the solar cell surface.

Effect of overtime work on cognitive function in automotive workers.

PubMed

Proctor, S P; White, R F; Robins, T G; Echeverria, D; Rocskay, A Z

1996-04-01

The present investigation examined whether increased overtime work predicts impairment in cognitive performance in the domains of attention, executive function, and mood. The behavioral and cognitive functions of 248 automotive workers were measured by a neurobehavioral test performance. Overtime, defined as number of hours worked greater than 8 h a day or greater than 5 d a week, was calculated from company payroll records for the week before the test day. The number of consecutive days worked before the test day was also determined. Cross-sectional data analysis by multiple linear regression, after adjustment for the effects of age, education, gender, alcohol intake, repeated grade in school, acute petroleum naphtha exposure, shift worked, job type, number of consecutive days worked before the test day, and number of hours worked on the test day before the testing, demonstrated that increased overtime was significantly associated with impaired performance on several tests of attention and executive function. Increased feelings of depression, fatigue, and confusion were also associated with increased overtime work. In addition significant interaction effects were observed for job type but not for naphtha exposure. The findings support the hypothesis that overtime work results in impaired cognitive performance in the areas of attention and executive function and that both overtime hours and the number of consecutive days worked prior to a test day affect mood.

Calibrated work function mapping by Kelvin probe force microscopy

NASA Astrophysics Data System (ADS)

Fernández Garrillo, Pablo A.; Grévin, Benjamin; Chevalier, Nicolas; Borowik, Łukasz

2018-04-01

We propose and demonstrate the implementation of an alternative work function tip calibration procedure for Kelvin probe force microscopy under ultrahigh vacuum, using monocrystalline metallic materials with known crystallographic orientation as reference samples, instead of the often used highly oriented pyrolytic graphite calibration sample. The implementation of this protocol allows the acquisition of absolute and reproducible work function values, with an improved uncertainty with respect to unprepared highly oriented pyrolytic graphite-based protocols. The developed protocol allows the local investigation of absolute work function values over nanostructured samples and can be implemented in electronic structures and devices characterization as demonstrated over a nanostructured semiconductor sample presenting Al0.7Ga0.3As and GaAs layers with variable thickness. Additionally, using our protocol we find that the work function of annealed highly oriented pyrolytic graphite is equal to 4.6 ± 0.03 eV.

Noradrenaline transporter blockade increases fronto-parietal functional connectivity relevant for working memory.

PubMed

Hernaus, Dennis; Casales Santa, Marta Ma; Offermann, Jan Stefan; Van Amelsvoort, Thérèse

2017-04-01

Experimental animal work has demonstrated that dopamine and noradrenaline play an essential role in modulating prefrontal cortex-mediated networks underlying working memory performance. Studies of functional connectivity have been instrumental in extending such notions to humans but, so far, have almost exclusively focussed on pharmacological agents with a predominant dopaminergic mechanism of action. Here, we investigate the effect of a single dose of atomoxetine 60mg, a noradrenaline transporter inhibitor, on working memory performance and associated functional connectivity during an n-back task in 19 healthy male volunteers. Atomoxetine increased functional connectivity between right anterior insula and dorsolateral prefrontal cortex, precentral gyrus, posterior parietal cortex and precuneus during the high-working memory load condition of the n-back task. Increased atomoxetine-induced insula-dorsolateral prefrontal cortex functional connectivity during this condition correlated with decreased reaction time variability and was furthermore predicted by working memory capacity. These results show for the first time that noradrenaline transporter blockade-induced increases in cortical catecholamines accentuate fronto-parietal working memory-related network integrity. The observation of significant inter-subject variability in response to atomoxetine has implications for inverted-U frameworks of dopamine and noradrenaline function, which could be useful to predict drug effects in clinical disorders with variable treatment response. Copyright © 2017 Elsevier B.V. and ECNP. All rights reserved.

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

PubMed

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.

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

PubMed

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.

Work-function calculations for a symmetrical total-charge-density profile at the metallic surface

NASA Astrophysics Data System (ADS)

Wojciechowski, K. F.; Sobańska-Nowotnik, M.

1983-07-01

It is shown that, if the total-charge-density profile nT(x) at the surface of jellium satisfies the Budd-Vannimenus constraint and also is a symmetrical function of x, relative to the ordinate axis, then the work-function variation versus the Wigner-Seitz radius rs does not depend on the form of nT(x). Also the simple linear-density profile is used to calculate the work function by application of the variational principle for the energy, including the first and second density-gradient corrections to the kinetic energy and the first gradient correction to the exchange and correlation energy. The results for the work function are in good agreement with the polycrystalline values for low-density metals.

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

PubMed

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

2016-01-01

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 functioning (WF), and to determine whether the associations differ between workers with different working-time arrangements. A cross-sectional study was conducted within the sampling frame of the 'Shift Your Work' study that examined the effect of irregular working-times in relation to health and functioning at work. We included N = 622 Dutch employees, of which N = 384 (62%) were shift-workers, N = 171 (27%) on-call workers and N = 67 (11%) day-workers. Overweight and obesity were defined as BMI 25-30 and ≥30, respectively. WF was assessed using the Work-Role Functioning Questionnaire. The prevalences of overweight and obesity were 48% and 10% in all workers, 49% and 11% in shift-workers, 45% and 10% in on-call workers, and 49% and 6% in day workers, respectively. In all workers, obesity was associated with lower WF scores for physical demands (adjusted estimate, aB = -5.5). In shift-workers, obesity was associated with lower WF scores for output and physical demands (aB = -8.8 and -6.8, respectively). In day and on-call workers, overweight and obesity were not associated with WF. Overweight and obesity are highly prevalent in the working population. Obesity might reduce the executive function performance beyond physical limitations, and limit the ability to accomplish tasks successfully, especially in shift workers. Copyright © 2015 Elsevier Ltd and The Ergonomics Society. All rights reserved.

Auditory and Visual Working Memory Functioning in College Students with Attention-Deficit/Hyperactivity Disorder and/or Learning Disabilities.

PubMed

Liebel, Spencer W; Nelson, Jason M

2017-12-01

We investigated the auditory and visual working memory functioning in college students with attention-deficit/hyperactivity disorder, learning disabilities, and clinical controls. We examined the role attention-deficit/hyperactivity disorder subtype status played in working memory functioning. The unique influence that both domains of working memory have on reading and math abilities was investigated. A sample of 268 individuals seeking postsecondary education comprise four groups of the present study: 110 had an attention-deficit/hyperactivity disorder diagnosis only, 72 had a learning disability diagnosis only, 35 had comorbid attention-deficit/hyperactivity disorder and learning disability diagnoses, and 60 individuals without either of these disorders comprise a clinical control group. Participants underwent a comprehensive neuropsychological evaluation, and licensed psychologists employed a multi-informant, multi-method approach in obtaining diagnoses. In the attention-deficit/hyperactivity disorder only group, there was no difference between auditory and visual working memory functioning, t(100) = -1.57, p = .12. In the learning disability group, however, auditory working memory functioning was significantly weaker compared with visual working memory, t(71) = -6.19, p < .001, d = -0.85. Within the attention-deficit/hyperactivity disorder only group, there were no auditory or visual working memory functioning differences between participants with either a predominantly inattentive type or a combined type diagnosis. Visual working memory did not incrementally contribute to the prediction of academic achievement skills. Individuals with attention-deficit/hyperactivity disorder did not demonstrate significant working memory differences compared with clinical controls. Individuals with a learning disability demonstrated weaker auditory working memory than individuals in either the attention-deficit/hyperactivity or clinical control groups. © The Author 2017. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Could High Mental Demands at Work Offset the Adverse Association Between Social Isolation and Cognitive Functioning? Results of the Population-Based LIFE-Adult-Study.

PubMed

Rodriguez, Francisca S; Schroeter, Matthias L; Witte, A Veronica; Engel, Christoph; Löffler, Markus; Thiery, Joachim; Villringer, Arno; Luck, Tobias; Riedel-Heller, Steffi G

2017-11-01

The study investigated whether high mental demands at work, which have shown to promote a good cognitive functioning in old age, could offset the adverse association between social isolation and cognitive functioning. Based on data from the population-based LIFE-Adult-Study, the association between cognitive functioning (Verbal Fluency Test, Trail Making Test B) and social isolation (Lubben Social Network Scale) as well as mental demands at work (O*NET database) was analyzed via linear regression analyses adjusted for age, sex, education, and sampling weights. Cognitive functioning was significantly lower in socially isolated individuals and in individuals working in low mental demands jobs-even in old age after retirement and even after taking into account the educational level. An interaction effect suggested stronger effects of mental demands at work in socially isolated than nonisolated individuals. The findings suggest that working in high mental-demand jobs could offset the adverse association between social isolation and cognitive functioning. Further research should evaluate how interventions that target social isolation and enhance mentally demanding activities promote a good cognitive functioning in old age. Copyright © 2017 American Association for Geriatric Psychiatry. Published by Elsevier Inc. All rights reserved.

Improving Work Functioning and Mental Health of Health Care Employees Using an E-Mental Health Approach to Workers' Health Surveillance: Pretest–Posttest Study

PubMed Central

Ketelaar, Sarah M.; Nieuwenhuijsen, Karen; Bolier, Linda; Smeets, Odile; Sluiter, Judith K.

2014-01-01

Background 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. Methods 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. Results 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 < 0.01). 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). Conclusion 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. PMID:25516815

Mental Vitality @ Work: The effectiveness of a mental module for workers' health surveillance for nurses and allied health professionals, comparing two approaches in a cluster-randomised controlled trial.

PubMed

Ketelaar, Sarah M; Nieuwenhuijsen, Karen; Gärtner, Fania R; Bolier, Linda; Smeets, Odile; Sluiter, Judith K

2014-07-01

The aim of this study was to compare two approaches for a worker's health surveillance (WHS) mental module on work functioning and work-related mental health. Nurses and allied health professionals from one organisation were cluster-randomised at ward level to e-mental health care (EMH) (N = 579) or occupational physician care (OP) (N = 591). Both groups received screening and personalised feedback on impaired work functioning and mental health. Positively screened participants received an invitation to follow a self-help EMH intervention, or for a consultation with an OP. The primary outcome was impaired work functioning. Follow-up was performed after 3 and 6 months. Linear mixed models were applied to determine differences. Non-inferiority of the EMH-care approach was demonstrated if the mean absolute improvement on work functioning in the OP-care group was ≤10 points higher than the EMH-care group. Analyses were performed on the positively screened participants (almost 80 %) (EMH N = 75; OP N = 108) and all participants (EMH N = 98; OP N = 142). Both groups improved over time regarding impaired work functioning. A considerable percentage of participants had improved relevantly at follow-up regarding work functioning (3 months: EMH 30 %, OP 46 %; 6 months: EMH 36 %, OP 41 %) compared to baseline. No statistically significant differences were found between the groups, and the difference did not exceed the pre-defined criterion for non-inferiority. The OP-care approach for a WHS mental module trended towards better performance in targeting work functioning, but our findings indicate that the EMH-care approach was non-inferior. However, the high dropout rate and low compliance to EMH interventions should be taken into account.

Development of an Instrument to Measure Behavioral Health Function for Work Disability: Item Pool Construction and Factor Analysis

PubMed Central

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

2014-01-01

Objectives To develop a broad set of claimant-reported items to assess behavioral health functioning relevant to the Social Security disability determination processes, and to evaluate the underlying structure of behavioral health functioning for use in development of a new functional assessment instrument. Design Cross-sectional. Setting Community. Participants Item pools of behavioral health functioning were developed, refined, and field-tested in a sample of persons applying for Social Security disability benefits (N=1015) who reported difficulties working due to mental or both mental and physical conditions. Interventions None. Main Outcome Measure Social Security Administration Behavioral Health (SSA-BH) measurement instrument Results Confirmatory factor analysis (CFA) specified that a 4-factor model (self-efficacy, mood and emotions, behavioral control, and social interactions) had the optimal fit with the data and was also consistent with our hypothesized conceptual framework for characterizing behavioral health functioning. When the items within each of the four scales were tested in CFA, the fit statistics indicated adequate support for characterizing behavioral health as a unidimensional construct along these four distinct scales of function. Conclusion This work represents a significant advance both conceptually and psychometrically in assessment methodologies for work related behavioral health. The measurement of behavioral health functioning relevant to the context of work requires the assessment of multiple dimensions of behavioral health functioning. Specifically, we identified a 4-factor model solution that represented key domains of work related behavioral health functioning. These results guided the development and scale formation of a new SSA-BH instrument. PMID:23548542

Development of an instrument to measure behavioral health function for work disability: item pool construction and factor analysis.

PubMed

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

2013-09-01

To develop a broad set of claimant-reported items to assess behavioral health functioning relevant to the Social Security disability determination processes, and to evaluate the underlying structure of behavioral health functioning for use in development of a new functional assessment instrument. Cross-sectional. Community. Item pools of behavioral health functioning were developed, refined, and field tested in a sample of persons applying for Social Security disability benefits (N=1015) who reported difficulties working because of mental or both mental and physical conditions. None. Social Security Administration Behavioral Health (SSA-BH) measurement instrument. Confirmatory factor analysis (CFA) specified that a 4-factor model (self-efficacy, mood and emotions, behavioral control, social interactions) had the optimal fit with the data and was also consistent with our hypothesized conceptual framework for characterizing behavioral health functioning. When the items within each of the 4 scales were tested in CFA, the fit statistics indicated adequate support for characterizing behavioral health as a unidimensional construct along these 4 distinct scales of function. This work represents a significant advance both conceptually and psychometrically in assessment methodologies for work-related behavioral health. The measurement of behavioral health functioning relevant to the context of work requires the assessment of multiple dimensions of behavioral health functioning. Specifically, we identified a 4-factor model solution that represented key domains of work-related behavioral health functioning. These results guided the development and scale formation of a new SSA-BH instrument. Copyright © 2013 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

Functional Magnetic Resonance Imaging of Working Memory and Executive Dysfunction in Systemic Lupus Erythematosus and Antiphospholipid Antibody-Positive Patients.

PubMed

Kozora, E; Uluğ, A M; Erkan, D; Vo, A; Filley, C M; Ramon, G; Burleson, A; Zimmerman, R; Lockshin, M D

2016-11-01

Standardized cognitive tests and functional magnetic resonance imaging (fMRI) studies of systemic lupus erythematosus (SLE) patients demonstrate deficits in working memory and executive function. These neurobehavioral abnormalities are not well studied in antiphospholipid syndrome, which may occur independently of or together with SLE. This study compares an fMRI paradigm involving motor skills, working memory, and executive function in SLE patients without antiphospholipid antibody (aPL) (the SLE group), aPL-positive non-SLE patients (the aPL-positive group), and controls. Brain MRI, fMRI, and standardized cognitive assessment results were obtained from 20 SLE, 20 aPL-positive, and 10 healthy female subjects with no history of neuropsychiatric abnormality. Analysis of fMRI data showed no differences in performance across groups on bilateral motor tasks. When analysis of variance was used, significant group differences were found in 2 executive function tasks (word generation and word rhyming) and in a working memory task (N-Back). Patients positive for aPL demonstrated higher activation in bilateral frontal, temporal, and parietal cortices compared to controls during working memory and executive function tasks. SLE patients also demonstrated bilateral frontal and temporal activation during working memory and executive function tasks. Compared to controls, both aPL-positive and SLE patients had elevated cortical activation, primarily in the frontal lobes, during tasks involving working memory and executive function. These findings are consistent with cortical overactivation as a compensatory mechanism for early white matter neuropathology in these disorders. © 2016, American College of Rheumatology.

Changes in working conditions and physical health functioning among midlife and ageing employees.

PubMed

Mänty, Minna; Kouvonen, Anne; Lallukka, Tea; Lahti, Jouni; Lahelma, Eero; Rahkonen, Ossi

2015-11-01

The aim this study was to examine the effect of changes in physical and psychosocial working conditions on physical health functioning among ageing municipal employees. Follow-up survey data were collected from midlife employees of the City of Helsinki, Finland, at three time points: wave 1 (2000-2002), wave 2 (2007), and wave 3 (2012). Changes in physical and psychosocial working conditions were assessed between waves 1 and 2. Physical health functioning was measured by the physical component summary (PCS) of the Short-Form 36 questionnaire at each of the three waves. In total, 2784 respondents (83% women) who remained employed over the follow-up were available for the analyses. Linear mixed-effect models were used to assess the associations and adjust for key covariates (age, gender, obesity, chronic diseases, and health behaviors). Repeated and increased exposure to adverse physical working conditions was associated with greater decline in physical health functioning over time. In contrast, decrease in exposures reduced the decline. Of the psychosocial working conditions, changes in job demands had no effects on physical health functioning. However, decreased job control was associated with greater decline and repeated high or increased job control reduced the decline in physical health functioning over time. Adverse changes in physical working conditions and job control were associated with greater decline in physical health functioning over time, whereas favorable changes in these exposures reduced the decline. Preventing deterioration and promoting improvement of working conditions are likely to help maintain better physical health functioning among ageing employees.

Work function characterization of solution-processed cobalt silicide

DOE PAGES

Ullah, Syed Shihab; Robinson, Matt; Hoey, Justin; ...

2012-05-08

Cobalt silicide thin films were prepared by spin-coating Si6H12-based inks onto various substrates followed by a thermal treatment. The work function of the solution processed Co-Si was determined by both capacitance-voltage (C-V) measurements of metal-oxide-semiconductor (MOS) structures as well as by ultraviolet photoelectron spectroscopy (UPS). The UPS-derived work function was 4.80 eV for a Co-Si film on Si (100) while C-V of MOS structures yielded a work function of 4.36 eV where the metal was solution-processed Co-Si, the oxide was SiO2 and the semiconductor was a B-doped Si wafer.

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

PubMed

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 between changes in neurocognitive and work functioning measures in this study. However, meaningful improvement in neurocognitive functioning with desvenlafaxine was associated with greater improvement in both mood and occupational outcomes. This suggests that addressing cognitive dysfunction may improve clinical and occupational outcomes in employed patients with MDD. However, the relationship between neurocognitive and work functioning in MDD is complex and requires further study. Copyright © 2016 Elsevier B.V. All rights reserved.

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

PubMed Central

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 helping people to switch off and unwind from work. PMID:27746759

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

PubMed

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 helping people to switch off and unwind from work.

Direct work function measurement by gas phase photoelectron spectroscopy and its application on PbS nanoparticles.

PubMed

Axnanda, Stephanus; Scheele, Marcus; Crumlin, Ethan; Mao, Baohua; Chang, Rui; Rani, Sana; Faiz, Mohamed; Wang, Suidong; Alivisatos, A Paul; Liu, Zhi

2013-01-01

Work function is a fundamental property of a material's surface. It is playing an ever more important role in engineering new energy materials and efficient energy devices, especially in the field of photovoltaic devices, catalysis, semiconductor heterojunctions, nanotechnology, and electrochemistry. Using ambient pressure X-ray photoelectron spectroscopy (APXPS), we have measured the binding energies of core level photoelectrons of Ar gas in the vicinity of several reference materials with known work functions (Au(111), Pt(111), graphite) and PbS nanoparticles. We demonstrate an unambiguously negative correlation between the work functions of reference samples and the binding energies of Ar 2p core level photoelectrons detected from the Ar gas near the sample surface region. Using this experimentally determined linear relationship between the surface work function and Ar gas core level photoelectron binding energy, we can measure the surface work function of different materials under different gas environments. To demonstrate the potential applications of this ambient pressure XPS technique in nanotechnology and solar energy research, we investigate the work functions of PbS nanoparticles with various capping ligands: methoxide, mercaptopropionic acid, and ethanedithiol. Significant Fermi level position changes are observed for PbS nanoparticles when the nanoparticle size and capping ligands are varied. The corresponding changes in the valence band maximum illustrate that an efficient quantum dot solar cell design has to take into account the electrochemical effect of the capping ligand as well.

Developing models of how cognitive improvements change functioning: Mediation, moderation and moderated mediation

PubMed Central

Wykes, Til; Reeder, Clare; Huddy, Vyv; Taylor, Rumina; Wood, Helen; Ghirasim, Natalia; Kontis, Dimitrios; Landau, Sabine

2012-01-01

Background Cognitive remediation (CRT) affects functioning but the extent and type of cognitive improvements necessary are unknown. Aim To develop and test models of how cognitive improvement transfers to work behaviour using the data from a current service. Method Participants (N49) with a support worker and a paid or voluntary job were offered CRT in a Phase 2 single group design with three assessments: baseline, post therapy and follow-up. Working memory, cognitive flexibility, planning and work outcomes were assessed. Results Three models were tested (mediation — cognitive improvements drive functioning improvement; moderation — post treatment cognitive level affects the impact of CRT on functioning; moderated mediation — cognition drives functioning improvements only after a certain level is achieved). There was evidence of mediation (planning improvement associated with improved work quality). There was no evidence that cognitive flexibility (total Wisconsin Card Sorting Test errors) and working memory (Wechsler Adult Intelligence Scale III digit span) mediated work functioning despite significant effects. There was some evidence of moderated mediation for planning improvement if participants had poorer memory and/or made fewer WCST errors. The total CRT effect on work quality was d = 0.55, but the indirect (planning-mediated CRT effect) was d = 0.082 Conclusion Planning improvements led to better work quality but only accounted for a small proportion of the total effect on work outcome. Other specific and non-specific effects of CRT and the work programme are likely to account for some of the remaining effect. This is the first time complex models have been tested and future Phase 3 studies need to further test mediation and moderated mediation models. PMID:22503640

5 CFR 551.424 - Time spent adjusting grievances or performing representational functions.

Code of Federal Regulations, 2010 CFR

2010-01-01

... hours of work. This includes time spent by an employee performing such functions during regular working... MANAGEMENT CIVIL SERVICE REGULATIONS PAY ADMINISTRATION UNDER THE FAIR LABOR STANDARDS ACT Hours of Work... shall be considered hours of work. (b) “Official time” granted an employee by an agency to perform...

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

ERIC Educational Resources Information Center

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…

Working memory capacity and the functional connectome - insights from resting-state fMRI and voxelwise centrality mapping.

PubMed

Markett, Sebastian; Reuter, Martin; Heeren, Behrend; Lachmann, Bernd; Weber, Bernd; Montag, Christian

2018-02-01

The functional connectome represents a comprehensive network map of functional connectivity throughout the human brain. To date, the relationship between the organization of functional connectivity and cognitive performance measures is still poorly understood. In the present study we use resting-state functional magnetic resonance imaging (fMRI) data to explore the link between the functional connectome and working memory capacity in an individual differences design. Working memory capacity, which refers to the maximum amount of context information that an individual can retain in the absence of external stimulation, was assessed outside the MRI scanner and estimated based on behavioral data from a change detection task. Resting-state time series were analyzed by means of voxelwise degree and eigenvector centrality mapping, which are data-driven network analytic approaches for the characterization of functional connectivity. We found working memory capacity to be inversely correlated with both centrality in the right intraparietal sulcus. Exploratory analyses revealed that this relationship was putatively driven by an increase in negative connectivity strength of the structure. This resting-state connectivity finding fits previous task based activation studies that have shown that this area responds to manipulations of working memory load.

Doped polymer semiconductors with ultrahigh and ultralow work functions for ohmic contacts.

PubMed

Tang, Cindy G; Ang, Mervin C Y; Choo, Kim-Kian; Keerthi, Venu; Tan, Jun-Kai; Syafiqah, Mazlan Nur; Kugler, Thomas; Burroughes, Jeremy H; Png, Rui-Qi; Chua, Lay-Lay; Ho, Peter K H

2016-11-24

To make high-performance semiconductor devices, a good ohmic contact between the electrode and the semiconductor layer is required to inject the maximum current density across the contact. Achieving ohmic contacts requires electrodes with high and low work functions to inject holes and electrons respectively, where the work function is the minimum energy required to remove an electron from the Fermi level of the electrode to the vacuum level. However, it is challenging to produce electrically conducting films with sufficiently high or low work functions, especially for solution-processed semiconductor devices. Hole-doped polymer organic semiconductors are available in a limited work-function range, but hole-doped materials with ultrahigh work functions and, especially, electron-doped materials with low to ultralow work functions are not yet available. The key challenges are stabilizing the thin films against de-doping and suppressing dopant migration. Here we report a general strategy to overcome these limitations and achieve solution-processed doped films over a wide range of work functions (3.0-5.8 electronvolts), by charge-doping of conjugated polyelectrolytes and then internal ion-exchange to give self-compensated heavily doped polymers. Mobile carriers on the polymer backbone in these materials are compensated by covalently bonded counter-ions. Although our self-compensated doped polymers superficially resemble self-doped polymers, they are generated by separate charge-carrier doping and compensation steps, which enables the use of strong dopants to access extreme work functions. We demonstrate solution-processed ohmic contacts for high-performance organic light-emitting diodes, solar cells, photodiodes and transistors, including ohmic injection of both carrier types into polyfluorene-the benchmark wide-bandgap blue-light-emitting polymer organic semiconductor. We also show that metal electrodes can be transformed into highly efficient hole- and electron-injection contacts via the self-assembly of these doped polyelectrolytes. This consequently allows ambipolar field-effect transistors to be transformed into high-performance p- and n-channel transistors. Our strategy provides a method for producing ohmic contacts not only for organic semiconductors, but potentially for other advanced semiconductors as well, including perovskites, quantum dots, nanotubes and two-dimensional materials.

A pilot study on factors involved with work participation in the early stages of multiple sclerosis.

PubMed

Van der Hiele, Karin; Middelkoop, Huub A M; Ruimschotel, Rob; Kamminga, Noëlle G A; Visser, Leo H

2014-01-01

Up to 30% of recently diagnosed MS patients lose their jobs in the first four years after diagnosis. Taking into account the personal and socio-economic importance of sustaining employment, it is of the utmost importance to examine factors involved with work participation. To investigate differences in self-reported functioning in recently diagnosed MS patients with and without a paid job. Self-reports of physical and cognitive functioning, depression, anxiety and fatigue were gathered from 44 relapsing-remitting MS patients diagnosed within 3 years. Patients with a paid job (57%) reported better physical functioning (p<0.001), better memory functioning (p = 0.01) and a lower physical impact of fatigue (p = 0.018) than patients without a paid job. Physical functioning was the main predictor of employment status in a logistic regression model. In those with a paid job better memory functioning (r = 0.54, p = 0.005) and a lower social impact of fatigue (r =  -0.46, p = 0.029) correlated with an increased number of working hours. Better physical functioning is the primary factor involved with increased work participation in early MS. Better self-reported memory functioning and less social fatigue were associated with increased working hours. These findings highlight the importance of battling these symptoms in the early stages of MS.

The Cognitive Symptom Checklist-Work in cancer patients is related with work functioning, fatigue and depressive symptoms: a validation study.

PubMed

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.

The electronic structures and work functions of (100) surface of typical binary and doped REB6 single crystals

NASA Astrophysics Data System (ADS)

Liu, Hongliang; Zhang, Xin; Xiao, Yixin; Zhang, Jiuxing

2018-03-01

The density function theory been used to calculate the electronic structures of binary and doped rare earth hexaborides (REB6), which exhibits the large density of states (DOS) near Fermi level. The d orbital elections of RE element contribute the electronic states of election emission near the Fermi level, which imply that the REB6 (RE = La, Ce, Gd) with wide distribution of high density d orbital electrons could provide a lower work function and excellent emission properties. Doping RE elements into binary REB6 can adjust DOS and the position of the Fermi energy level. The calculated work functions of considered REB6 (100) surface show that the REB6 (RE = La, Ce, Gd) have lower work function and doping RE elements with active d orbital electrons can significantly reduce work function of binary REB6. The thermionic emission test results are basically accordant with the calculated value, proving the first principles calculation could provide a good theoretical guidance for the study of electron emission properties of REB6.

Psychosocial work characteristics and social support as predictors of SF-36 health functioning: the Whitehall II study.

PubMed

Stansfeld, S A; Bosma, H; Hemingway, H; Marmot, M G

1998-01-01

To assess whether work characteristics and social support are predictors of physical, psychological, and social functioning. Work characteristics (Karasek and Siegrist models) and social support at baseline were used to predict health functioning measured by the SF-36 General Health Survey 5 years later in a prospective cohort study of 10,308 British male and female civil servants. Effort-reward imbalance and negative aspects of close relationships predicted poor physical, psychological, and social functioning after adjustment for the potential confounding effects of age, employment grade, baseline ill health, and negative affectivity. These psychosocial characteristics seem to act in a similar way in the healthy and those with existing illness. Psychological demands at work in women, and low confiding/emotional support in men, also predicted poor functioning. Etiologically. these effects are not mediated through health-related behaviors. Negative aspects of work (high demands and effort-reward imbalance) and negative aspects of close relationships are independent powerful predictors of poor health functioning. They may have an etiological role, which is independent of baseline illness.

Exploring the relations among physical fitness, executive functioning, and low academic achievement.

PubMed

de Bruijn, A G M; Hartman, E; Kostons, D; Visscher, C; Bosker, R J

2018-03-01

Physical fitness seems to be related to academic performance, at least when taking the role of executive functioning into account. This assumption is highly relevant for the vulnerable population of low academic achievers because their academic performance might benefit from enhanced physical fitness. The current study examined whether physical fitness and executive functioning are independent predictors of low mathematics and spelling achievement or whether the relation between physical fitness and low achievement is mediated by specific executive functions. In total, 477 students from second- and third-grade classes of 12 primary schools were classified as either low or average-to-high achievers in mathematics and spelling based on their scores on standardized achievement tests. Multilevel structural equation models were built with direct paths between physical fitness and academic achievement and added indirect paths via components of executive functioning: inhibition, verbal working memory, visuospatial working memory, and shifting. Physical fitness was only indirectly related to low achievement via specific executive functions, depending on the academic domain involved. Verbal working memory was a mediator between physical fitness and low achievement in both domains, whereas visuospatial working memory had a mediating role only in mathematics. Physical fitness interventions aiming to improve low academic achievement, thus, could potentially be successful. The mediating effect of executive functioning suggests that these improvements in academic achievement will be preceded by enhanced executive functions, either verbal working memory (in spelling) or both verbal and visuospatial working memory (in mathematics). Copyright © 2017 Elsevier Inc. All rights reserved.

Self versus informant reports on the specific levels of functioning scale: Relationships to depression and cognition in schizophrenia and schizoaffective disorder.

PubMed

Ermel, Julia; Carter, Cameron S; Gold, James M; MacDonald, Angus W; Daniel Ragland, J; Silverstein, Steven M; Strauss, Milton E; Barch, Deanna M

2017-09-01

The goal of the current study was to examine the relationships between insight and both cognitive function and depression in schizophrenia and schizoaffective disorder, and to determine if there were similar relationships across diagnostic categories. We examined discrepancies between self and informant reports of function on the Specific levels of function scale as a metric of insight for interpersonal, social acceptance, work and activities. We examined two samples of individuals with schizophrenia and/or schizoaffective disorder (Ns of 188 and 67 respectively). In Sample 1, cognition was measured using the Dot Probe Expectancy Task. In Sample 2, cognition was measured by averaging several subtests from the MATRICS consensus cognitive battery, as well as additional measures of working memory. In both samples, depression was measured using the Brief Psychiatric Rating Scale. In both samples, we found significant relationships between worse cognition and overestimations of work function, as well as between higher depression levels and underestimation of interpersonal function. These relationships were specific to interpersonal and work function, with significantly stronger correlations with interpersonal and work function compared to the other areas of function. Similar results were found across diagnostic categories. These results have important implications for treatment planning, as they suggest the need to take into account depression and cognitive function when evaluating the patient's self-report of function, and highlight the utility of informant reports in evaluating function and treatment planning. Further, they add to the literature on the similarity across schizophrenia and schizoaffective disorder in a variety of pathological mechanisms.

Properties of real metallic surfaces: Effects of density functional semilocality and van der Waals nonlocality

PubMed Central

Patra, Abhirup; Bates, Jefferson E.; Sun, Jianwei; Perdew, John P.

2017-01-01

We have computed the surface energies, work functions, and interlayer surface relaxations of clean (111), (100), and (110) surfaces of Al, Cu, Ru, Rh, Pd, Ag, Pt, and Au. We interpret the surface energy from liquid metal measurements as the mean of the solid-state surface energies over these three lowest-index crystal faces. We compare experimental (and random phase approximation) reference values to those of a family of nonempirical semilocal density functionals, from the basic local density approximation (LDA) to our most advanced general purpose meta-generalized gradient approximation, strongly constrained and appropriately normed (SCAN). The closest agreement is achieved by the simplest density functional LDA, and by the most sophisticated one, SCAN+rVV10 (Vydrov–Van Voorhis 2010). The long-range van der Waals interaction, incorporated through rVV10, increases the surface energies by about 10%, and increases the work functions by about 3%. LDA works for metal surfaces through two known error cancellations. The Perdew–Burke–Ernzerhof generalized gradient approximation tends to underestimate both surface energies (by about 24%) and work functions (by about 4%), yielding the least-accurate results. The amount by which a functional underestimates these surface properties correlates with the extent to which it neglects van der Waals attraction at intermediate and long range. Qualitative arguments are given for the signs of the van der Waals contributions to the surface energy and work function. A standard expression for the work function in Kohn–Sham (KS) theory is shown to be valid in generalized KS theory. Interlayer relaxations from different functionals are in reasonable agreement with one another, and usually with experiment. PMID:29042509

Long-term Effects of Psychosocial Work Stress in Midlife on Health Functioning After Labor Market Exit—Results From the GAZEL Study

PubMed Central

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

2012-01-01

Objectives. 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. Methods. 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. Results. 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 (R²: 0.13) compared with the demand-control model (R²: 0.11). Conclusions. Findings underline the importance of working conditions in midlife not only for health in midlife but also for health functioning after labor market exit. PMID:22546992

Chronic stress effects on working memory: association with prefrontal cortical tyrosine hydroxylase.

PubMed

Lee, Young-A; Goto, Yukiori

2015-06-01

Chronic stress causes deficits in cognitive function including working memory, for which transmission of such catecholamines as dopamine and noradrenaline transmission in the prefrontal cortex (PFC) are crucial. Since catecholamine synthesis depends on the rate-limiting enzyme, tyrosine hydroxylase (TH), TH is thought to play an important role in PFC function. In this study, we found that two distinct population existed in Sprague-Dawley rats in terms of working memory capacity, one with higher working memory capacity, and the other with low capacity. This distinction of working memory capacity became apparent after rats were exposed to chronic stress. In addition, such working memory capacity and alterations of working memory function by chronic stress were associated with TH expression in the PFC. Copyright © 2015 Elsevier B.V. All rights reserved.

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

PubMed

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.

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

ERIC Educational Resources Information Center

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…

Nascent Function Concepts in Nova Scientia

ERIC Educational Resources Information Center

Groetsch, C. W.

2004-01-01

The origin of the function concept is usually traced to Galileo's work on motion. We argue that specific proto-function concepts appeared in the work of Tartaglia a century before the publication of Galileo's Two New Sciences. The study of Tartaglia's ideas can be used in the classroom as a historical introduction to various function concepts,…

Attained Functional Status Moderates Survival Outcomes of Return to Work After Lung Transplantation.

PubMed

Tumin, Dmitry; Kirkby, Stephen E; Tobias, Joseph D; Hayes, Don

2016-06-01

Returning to work is a desirable outcome of lung transplantation that is selective on attained functional status. Survival implications of post-transplant employment are unclear. The United Network for Organ Sharing registry was queried for first-time lung transplants performed from May 2005 to March 2015 in patients ages 18-64. Attainment of normal functional status post-transplant, defined as a 100 % score on the Karnofsky Performance Scale (KPS), was examined as moderating 5-year survival outcomes of work resumption, using Cox proportional hazards models. Supplemental analysis examined attainment of forced expiratory volume in 1 s (FEV1) ≥80 % predicted as moderating survival implications of post-transplant employment. Of 10,066 patients, 1824 (18 %) returned to work, while 9078 contributed follow-up data on functional status. Multivariable analysis demonstrated a protective effect of work resumption among patients who did not attain normal functional status before returning to work (HR = 0.62; 95 % CI = 0.51, 0.76; p < 0.001). This association was attenuated among transplant recipients who reached 100 % KPS while still unemployed (p < 0.001). Similarly, post-transplant survival was favorably associated with 5-year survival among patients who did not attain at least 80 % predicted FEV1 before returning to work (HR = 0.71; 95 % CI = 0.59, 0.86; p < 0.001). Early return to work after lung transplantation may benefit patients experiencing mild functional limitations. Timing the resumption of employment to coincide with attainment of maximal functional status around 1 year post transplant should be considered.

Depressive and anxiety disorders on-the-job: the importance of job characteristics for good work functioning in persons with depressive and anxiety disorders.

PubMed

Plaisier, Inger; de Graaf, Ron; de Bruijn, Jeanne; Smit, Johannes; van Dyck, Richard; Beekman, Aartjan; Penninx, Brenda

2012-12-30

This study examines the importance of job characteristics on absence and on-the-job performance in a large group of employees with diagnosed depressive and anxiety disorders. In a sample of 1522 employees (1129 persons with and 393 persons without psychopathology) participating in Netherlands Study of Depression and Anxiety (NESDA, n=2981) we examined associations between job characteristics and work functioning (absenteeism and work performance) in multinominal logistic regression models. Job characteristics were working hours, psychosocial working conditions and occupational status. As expected, depressed and anxious patients were at significantly elevated risk for absenteeism and poor work performance. In analyses adjusted for psychopathology, absenteeism and poor performance were significantly lower among persons reporting high job support, high job control, less working hours, self-employed and high skilled jobs. Associations were comparable between persons with and without psychopathology. High job support, high job control and reduced working hours were partially related to work functioning in both workers with- and without-psychopathology. Since depressed and anxious employees are at a substantially increased risk for absenteeism and poor work performance, strategies that improve job support and feelings of control at work may be especially helpful to prevent poor work functioning in this at-risk group of employees. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Large Work Function Modulation of Monolayer MoS2 by Ambient Gases.

PubMed

Lee, Si Young; Kim, Un Jeong; Chung, JaeGwan; Nam, Honggi; Jeong, Hye Yun; Han, Gang Hee; Kim, Hyun; Oh, Hye Min; Lee, Hyangsook; Kim, Hyochul; Roh, Young-Geun; Kim, Jineun; Hwang, Sung Woo; Park, Yeonsang; Lee, Young Hee

2016-06-28

Although two-dimensional monolayer transition-metal dichalcogenides reveal numerous unique features that are inaccessible in bulk materials, their intrinsic properties are often obscured by environmental effects. Among them, work function, which is the energy required to extract an electron from a material to vacuum, is one critical parameter in electronic/optoelectronic devices. Here, we report a large work function modulation in MoS2 via ambient gases. The work function was measured by an in situ Kelvin probe technique and further confirmed by ultraviolet photoemission spectroscopy and theoretical calculations. A measured work function of 4.04 eV in vacuum was converted to 4.47 eV with O2 exposure, which is comparable with a large variation in graphene. The homojunction diode by partially passivating a transistor reveals an ideal junction with an ideality factor of almost one and perfect electrical reversibility. The estimated depletion width obtained from photocurrent mapping was ∼200 nm, which is much narrower than bulk semiconductors.

Postadsorption Work Function Tuning via Hydrogen Pressure Control

PubMed Central

2015-01-01

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. PMID:26692915

Attentional and Executive Function Behaviours in Children with Poor Working Memory

ERIC Educational Resources Information Center

Gathercole, Susan E.; Alloway, Tracy P.; Kirkwood, Hannah J.; Elliott, Julian G.; Holmes, Joni; Hilton, Kerry A.

2008-01-01

The purpose of this study was to explore the profiles of classroom behaviour relating to attention and executive functions in children with very poor working memory, and to test the hypothesis that inattentive behaviour and working memory problems co-occur. Teachers rated problem behaviours of 52 children with low working memory scores aged 5/6…

Executive Functions as Moderators of the Worked Example Effect: When Shifting Is More Important than Working Memory Capacity

ERIC Educational Resources Information Center

Schwaighofer, Matthias; Bühner, Markus; Fischer, Frank

2016-01-01

Worked examples have proven to be effective for knowledge acquisition compared with problem solving, particularly when prior knowledge is low (e.g., Kalyuga, 2007). However, in addition to prior knowledge, executive functions and fluid intelligence might be potential moderators of the effectiveness of worked examples. The present study examines…

Predictive value and construct validity of the work functioning screener-healthcare (WFS-H).

PubMed

Boezeman, Edwin J; Nieuwenhuijsen, Karen; Sluiter, Judith K

2016-05-25

To test the predictive value and convergent construct validity of a 6-item work functioning screener (WFS-H). Healthcare workers (249 nurses) completed a questionnaire containing the work functioning screener (WFS-H) and a work functioning instrument (NWFQ) measuring the following: cognitive aspects of task execution and general incidents, avoidance behavior, conflicts and irritation with colleagues, impaired contact with patients and their family, and level of energy and motivation. Productivity and mental health were also measured. Negative and positive predictive values, AUC values, and sensitivity and specificity were calculated to examine the predictive value of the screener. Correlation analysis was used to examine the construct validity. The screener had good predictive value, since the results showed that a negative screener score is a strong indicator of work functioning not hindered by mental health problems (negative predictive values: 94%-98%; positive predictive values: 21%-36%; AUC:.64-.82; sensitivity: 42%-76%; and specificity 85%-87%). The screener has good construct validity due to moderate, but significant (p<.001), associations with productivity (r=.51), mental health (r=.48), and distress (r=.47). The screener (WFS-H) had good predictive value and good construct validity. Its score offers occupational health professionals a helpful preliminary insight into the work functioning of healthcare workers.

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

PubMed

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.

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

PubMed

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, especially in brain regions involved in working memory performance. Copyright © 2014 Elsevier Inc. All rights reserved.

Luigi Gatteschi's work on asymptotics of special functions and their zeros

NASA Astrophysics Data System (ADS)

Gautschi, Walter; Giordano, Carla

2008-12-01

A good portion of Gatteschi's research publications-about 65%-is devoted to asymptotics of special functions and their zeros. Most prominently among the special functions studied figure classical orthogonal polynomials, notably Jacobi polynomials and their special cases, Laguerre polynomials, and Hermite polynomials by implication. Other important classes of special functions dealt with are Bessel functions of the first and second kind, Airy functions, and confluent hypergeometric functions, both in Tricomi's and Whittaker's form. This work is reviewed here, and organized along methodological lines.

Who Works Among Older Black and White, Well-Functioning Adults in the Health, Aging, and Body Composition Study?

PubMed Central

Rooks, Ronica N.; Simonsick, Eleanor M.; Schulz, Richard; Rubin, Susan; Harris, Tamara

2017-01-01

Objective: The aim of this study is to examine social, economic, and health factors related to paid work in well-functioning older adults and if and how these factors vary by race. Method: We used sex-stratified logistic and multinomial logistic regression to examine cross-sectional data in the Health, Aging, and Body Composition cohort study. The sample included 3,075 community-dwelling Black (42%) and White adults aged 70 to 79 at baseline. Results: Multinomial logistic regression analyses show Black men were more likely to work full-time, and Black women were more likely to work part-time. Men with ≥US$50,000 family income were more likely to work full-time. Men with better physical functioning were more likely to work full- and part-time. Women with ≥US$50,000 family income and fewer chronic diseases were more likely to work full-time. Women who were overweight and had fewer chronic diseases were more likely to work part-time. Discussion: Results suggest that well-functioning, older Black adults were more likely to work than their White counterparts, and working relates to better health and higher income, providing support for a productive or successful aging perspective. PMID:28894767

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

NASA Astrophysics Data System (ADS)

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.

Enhancing the accuracy of the Fowler method for monitoring non-constant work functions

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

Friedl, R., E-mail: roland.friedl@physik.uni-augsburg.de

2016-04-15

The Fowler method is a prominent non-invasive technique to determine the absolute work function of a surface based on the photoelectric effect. The evaluation procedure relies on the correlation of the photocurrent with the incident photon energy hν which is mainly dependent on the surface work function χ. Applying Fowler’s theory of the photocurrent, the measurements can be fitted by the theoretical curve near the threshold hν⪆χ yielding the work function χ and a parameter A. The straightforward experimental implementation of the Fowler method is to use several particular photon energies, e.g. via interference filters. However, with a realization likemore » that the restriction hν ≈ χ can easily be violated, especially when the work function of the material is decreasing during the measurements as, for instance, with coating or adsorption processes. This can lead to an overestimation of the evaluated work function value of typically some 0.1 eV, reaching up to more than 0.5 eV in an unfavorable case. A detailed analysis of the Fowler theory now reveals the background of that effect and shows that the fit-parameter A can be used to assess the accuracy of the determined value of χ conveniently during the measurements. Moreover, a scheme is introduced to quantify a potential overestimation and to perform a correction to χ to a certain extent. The issues are demonstrated exemplarily at the monitoring of the work function reduction of a stainless steel sample surface due to caesiation.« less

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

NASA Astrophysics Data System (ADS)

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 duration work shifts. These findings indicate that extended duration work shifts present a significant challenge to crewmembers and mission support specialists during long-duration space mission operations. Future research is needed to evaluate the efficacy of alternative work schedules and the development and implementation of more effective countermeasures will be required to maintain high levels of performance.

Functioning, coping and work status three years after participating in an interdisciplinary, occupational rehabilitation program.

PubMed

Øyeflaten, Irene; Midtgarden, Inger Johanne; Maeland, Silje; Eriksen, Hege R; Magnussen, Liv Heide

2014-07-01

The aim of this study was to explore how functional ability, coping and health were related to work and benefit status three years after participating in a four-week inpatient interdisciplinary occupational rehabilitation program. The cohort consisted of 338 individuals (75% females, mean age 51 years (SD=8.6)) who three years earlier had participated in a comprehensive inpatient interdisciplinary occupational rehabilitation program, due to long-term sick leave. The participants answered standardised questionnaires about subjective health complaints, functional ability, coping, and current work and benefit status. The relationships between these variables were analysed using logistic regression analyses. At the time of the survey, 59% of the participants worked at least 50% of a full working day. Twenty-five percent received at least 50% disability pension and 16% received other benefits. Poor functional ability (OR 4.8; CI 3.0-7.6), poor general health (OR 3.8; CI 2.3-6.1), high level of subjective health complaints (OR 3.3; CI 2.1-5.2), low coping (OR 2.8; CI 1.7-4.4), poor physical fitness (OR 2.8; CI 1.7-4.6) and poor sleep quality (OR 2.4; CI 1.5-3.7) were associated with receiving allowances. In a fully adjusted model, only poor functional ability and low coping were associated with receiving allowances three years after occupational rehabilitation. Functional ability and coping were the variables most strongly associated with not having returned to work. More attention should therefore be paid to enhance these factors in occupational rehabilitation programs. Part-time work may be a feasible way to integrate individuals with reduced workability in working life, if the alternative is complete absence from work. © 2014 the Nordic Societies of Public Health.

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

PubMed

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.

20 CFR 220.126 - Relationship of ability to do work and residual functional capacity.

Code of Federal Regulations, 2011 CFR

2011-04-01

... residual functional capacity. 220.126 Section 220.126 Employees' Benefits RAILROAD RETIREMENT BOARD... Relationship of ability to do work and residual functional capacity. (a) If the claimant can do his or her... not disabled. (b) If the residual functional capacity is not enough for the claimant to do any of his...

Physical and psychosocial prerequisites of functioning in relation to work ability and general subjective well-being among office workers.

PubMed

Sjögren-Rönkä, Tuulikki; Ojanen, Markku T; Leskinen, Esko K; Tmustalampi, Sirpa; Mälkiä, Esko A

2002-06-01

The purpose of the study was to investigate the physical and psychological prerequisites of functioning, as well as the social environment at work and personal factors, in relation to work ability and general subjective well-being in a group of office workers. The study was a descriptive cross-sectional investigation, using path analysis, of office workers. The subjects comprised 88 volunteers, 24 men and 64 women, from the same workplace [mean age 45.7 (SD 8.6) years]. The independent variables were measured using psychosocial and physical questionnaires and physical measurements. The first dependent variable, work ability, was measured by a work ability index. The second dependent variable, general subjective well-being, was assessed by life satisfaction and meaning of life. The variables were structured according to a modified version of the International Classification of Functioning, Disability and Health. Forward flexion of the spine, intensity of musculoskeletal symptoms, self-confidence, and mental stress at work explained 58% of work ability and had indirect effects on general subjective well-being. Self-confidence, mood, and work ability had a direct effect on general subjective well-being. The model developed explained 68% of general subjective well-being. Age played a significant role in this study population. The prerequisites of physical functioning are important in maintaining work ability, particularly among aging workers, and psychological prerequisites of functioning are of even greater importance in maintaining general subjective well-being.

Bio-psychosocial factors are associated with pain intensity, physical functioning, and ability to work in female healthcare personnel with recurrent low back pain.

PubMed

Taulaniemi, Annika; Kuusinen, Lotta; Tokola, Kari; Kankaanpää, Markku; Suni, Jaana H

2017-08-31

To investigate associations of various bio-psychosocial factors with bodily pain, physical func-tioning, and ability to work in low back pain. Cross-sectional study. A total of 219 female healthcare workers with recurrent non-specific low back pain. Associations between several physical and psychosocial factors and: (i) bodily pain, (ii) physical functioning and (iii) ability to work were studied. Variables with statistically significant associations (p < 0.05) in bivariate analysis were set within a generalized linear model to analyse their relationship with each dependent variable. In generalized linear model analysis, perceived work-induced lumbar exertion (p < 0.001), multi-site pain (p <0.001) and work-related fear-avoidance beliefs (FAB-W) (p = 0.02) best explained bodily pain. Multi-site pain (p < 0.001), lumbar exertion (p = 0.005), FAB-W (p = 0.01) and physical performance in figure-of-eight running (p = 0.01) and modified push-ups (p = 0.05) best explained physical functioning; FAB-W (p <0.001), lumbar exertion (p = 0.003), depression (p = 0.01) and recovery after work (p = 0.03) best explained work ability. In bivariate analysis lumbar exertion was associated with poor physical performance. FAB-W and work-induced lumbar exertion were associated with levels of pain, physical functioning and ability to work. Poor physical performance capacity was associated with work-induced lumbar exertion. Interventions that aim to reduce fear-avoidance and increase fitness capacity might be beneficial.

Electron Thermionic Emission from Graphene and a Thermionic Energy Converter

NASA Astrophysics Data System (ADS)

Liang, Shi-Jun; Ang, L. K.

2015-01-01

In this paper, we propose a model to investigate the electron thermionic emission from single-layer graphene (ignoring the effects of the substrate) and to explore its application as the emitter of a thermionic energy converter (TIC). An analytical formula is derived, which is a function of the temperature, work function, and Fermi energy level. The formula is significantly different from the traditional Richardson-Dushman (RD) law for which it is independent of mass to account for the supply function of the electrons in the graphene behaving like massless fermion quasiparticles. By comparing with a recent experiment [K. Jiang et al., Nano Res. 7, 553 (2014)] measuring electron thermionic emission from suspended single-layer graphene, our model predicts that the intrinsic work function of single-layer graphene is about 4.514 eV with a Fermi energy level of 0.083 eV. For a given work function, a scaling of T3 is predicted, which is different from the traditional RD scaling of T2. If the work function of the graphene is lowered to 2.5-3 eV and the Fermi energy level is increased to 0.8-0.9 eV, it is possible to design a graphene-cathode-based TIC operating at around 900 K or lower, as compared with the metal-based cathode TIC (operating at about 1500 K). With a graphene-based cathode (work function=4.514 eV ) at 900 K and a metallic-based anode (work function=2.5 eV ) like LaB6 at 425 K, the efficiency of our proposed TIC is about 45%.

Methodology to Support Dynamic Function Allocation Policies Between Humans and Flight Deck Automation

NASA Technical Reports Server (NTRS)

Johnson, Eric N.

2012-01-01

Function allocation assigns work functions to all agents in a team, both human and automation. Efforts to guide function allocation systematically have been studied in many fields such as engineering, human factors, team and organization design, management science, cognitive systems engineering. Each field focuses on certain aspects of function allocation, but not all; thus, an independent discussion of each does not address all necessary aspects of function allocation. Four distinctive perspectives have emerged from this comprehensive review of literature on those fields: the technology-centered, human-centered, team-oriented, and work-oriented perspectives. Each perspective focuses on different aspects of function allocation: capabilities and characteristics of agents (automation or human), structure and strategy of a team, and work structure and environment. This report offers eight issues with function allocation that can be used to assess the extent to which each of issues exist on a given function allocation. A modeling framework using formal models and simulation was developed to model work as described by the environment, agents, their inherent dynamics, and relationships among them. Finally, to validate the framework and metrics, a case study modeled four different function allocations between a pilot and flight deck automation during the arrival and approach phases of flight.

A Pilot Study on Factors Involved with Work Participation in the Early Stages of Multiple Sclerosis

PubMed Central

Van der Hiele, Karin; Middelkoop, Huub A. M.; Ruimschotel, Rob; Kamminga, Noëlle G. A.; Visser, Leo H.

2014-01-01

Background Up to 30% of recently diagnosed MS patients lose their jobs in the first four years after diagnosis. Taking into account the personal and socio-economic importance of sustaining employment, it is of the utmost importance to examine factors involved with work participation. Objective To investigate differences in self-reported functioning in recently diagnosed MS patients with and without a paid job. Methods Self-reports of physical and cognitive functioning, depression, anxiety and fatigue were gathered from 44 relapsing-remitting MS patients diagnosed within 3 years. Results Patients with a paid job (57%) reported better physical functioning (p<0.001), better memory functioning (p = 0.01) and a lower physical impact of fatigue (p = 0.018) than patients without a paid job. Physical functioning was the main predictor of employment status in a logistic regression model. In those with a paid job better memory functioning (r = 0.54, p = 0.005) and a lower social impact of fatigue (r = −0.46, p = 0.029) correlated with an increased number of working hours. Conclusion Better physical functioning is the primary factor involved with increased work participation in early MS. Better self-reported memory functioning and less social fatigue were associated with increased working hours. These findings highlight the importance of battling these symptoms in the early stages of MS. PMID:25153710

Theoretical study of cathode surfaces and high-temperature superconductors

NASA Technical Reports Server (NTRS)

Mueller, Wolfgang

1994-01-01

The surface-dipole properties of model cathode surfaces have been investigated with relativistic scattered-wave cluster calculations. Work-function/coverage curves have been derived from these data by employing the depolarization model of interacting surface dipoles. Accurate values have been obtained for the minimum work functions of several low-work-function surfaces. In the series BaO on bcc W, hcp Os, and fcc Pt, BaO/Os shows a lower and BaO/Pt a higher work function than BaO/W, which is attributed to the different substrate crystal structures involved. Results are also presented on the electronic structure of the high-temperature superconductor YBa2Cu3O7, which has been investigated with fully relativistic calculations for the first time.

Perceived functional ability assessed with the spinal function sort: is it valid for European rehabilitation settings in patients with non-specific non-acute low back pain?

PubMed Central

Hilfiker, R.; Kool, J. P.; Bachmann, S.; Hagen, K. B.

2010-01-01

The aim of this study involving 170 patients suffering from non-specific low back pain was to test the validity of the spinal function sort (SFS) in a European rehabilitation setting. The SFS, a picture-based questionnaire, assesses perceived functional ability of work tasks involving the spine. All measurements were taken by a blinded research assistant; work status was assessed with questionnaires. Our study demonstrated a high internal consistency shown by a Cronbach’s alpha of 0.98, reasonable evidence for unidimensionality, spearman correlations of >0.6 with work activities, and discriminating power for work status at 3 and 12 months by ROC curve analysis (area under curve = 0.760 (95% CI 0.689–0.822), respectively, 0.801 (95% CI 0.731–0.859). The standardised response mean within the two treatment groups was 0.18 and −0.31. As a result, we conclude that the perceived functional ability for work tasks can be validly assessed with the SFS in a European rehabilitation setting in patients with non-specific low back pain, and is predictive for future work status. PMID:20490874

The role of job strain on return to work after carpal tunnel surgery

PubMed Central

Gimeno, D; Amick, B; Habeck, R; Ossmann, J; Katz, J

2005-01-01

Aims: To examine the impact of job strain (that is, high psychological job demands and low job control) on return to work and work role functioning at two months, six months, or both, following carpal tunnel release surgery. Methods: A community based cohort of carpal tunnel syndrome (CTS) patients from physician practices was recruited between April 1997 and October 1998 throughout Maine (USA). 128 patients at two months and 122 at six months completed all relevant questions. A three level outcome variable indicated whether patients had: (1) returned to work functioning successfully, (2) returned to work functioning with limitations, or (3) not returned to work for health reasons. Two job strain measures were created: one, by combining psychological job demands and job control; and two, by dividing demands by control. Ordinal logistic regression was used to identify predictors of the three level work outcome variable. Results: After adjustment, workers with high demands and high control (active work) were less likely to successfully return to work (OR = 0.22; p = 0.014) at two months. Having a job with higher demands than job control (high strain) predicted not returning to work or returning to work but not successfully meeting job demands (OR = 0.14; p = 0.001), at six months. Conclusions: The findings underscore the role of psychosocial work conditions, as defined by the Karasek demand-control model, in explaining a worker's return to work. Clinicians, researchers, and employers should consider a multidimensional and integrative model of successful work role functioning upon return to work. Moreover, since the evidence of the effects of work process changes on the reduction of CTS is very scarce, these findings point to the opportunity for collaborative workplace interventions to facilitate successful return to work. PMID:16234404

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

PubMed Central

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

No differences in performance on test of working memory and executive functioning between healthy elderly postmenopausal women using or not using hormone therapy.

PubMed

Grigorova, M; Sherwin, B B

2006-06-01

On average, ovarian function ceases at the age of 52 years so that estrogen (E) levels are chronically low following the menopause. Numerous studies have found that hormone therapy (HT) helps to protect verbal memory, a hippocampal function. Estrogen receptors are also found in the prefrontal cortex (PFC), suggesting that estrogen may modulate executive and working memory functions, both mediated by the PFC. The possible role of progesterone (P) on executive functions and working memory is unknown. To examine the relationship between neuropsychological performance, age of initiation of HT, and duration of HT use. In this cross-sectional study, the neuropsychological performance of 37 postmenopausal women (mean age, 65 years) who used either estrogen-only or sequential E + P (E-alone group)(n = 22) or E + P continuously (n = 15) was compared to that of 28 healthy postmenopausal women matched for age and education who had never used HT. It was hypothesized that the E-only users would perform better then the E + P and the never-users on neuropsychological tests of verbal memory, executive function and working memory. Results showed only minor between-group differences on working memory scores such that the E + P users were slowest to generate a response on the N-Back test of working memory. No group differences on tests of executive functions were found. There was no relationship between neuropsychological performance, age of initiation of HT, or duration of HT use.

Hartree-Fock theory of the inhomogeneous electron gas at a jellium metal surface: Rigorous upper bounds to the surface energy and accurate work functions

NASA Astrophysics Data System (ADS)

Sahni, V.; Ma, C. Q.

1980-12-01

The inhomogeneous electron gas at a jellium metal surface is studied in the Hartree-Fock approximation by Kohn-Sham density functional theory. Rigorous upper bounds to the surface energy are derived by application of the Rayleigh-Ritz variational principle for the energy, the surface kinetic, electrostatic, and nonlocal exchange energy functionals being determined exactly for the accurate linear-potential model electronic wave functions. The densities obtained by the energy minimization constraint are then employed to determine work-function results via the variationally accurate "displaced-profile change-in-self-consistent-field" expression. The theoretical basis of this non-self-consistent procedure and its demonstrated accuracy for the fully correlated system (as treated within the local-density approximation for exchange and correlation) leads us to conclude these results for the surface energies and work functions to be essentially exact. Work-function values are also determined by the Koopmans'-theorem expression, both for these densities as well as for those obtained by satisfaction of the constraint set on the electrostatic potential by the Budd-Vannimenus theorem. The use of the Hartree-Fock results in the accurate estimation of correlation-effect contributions to these surface properties of the nonuniform electron gas is also indicated. In addition, the original work and approximations made by Bardeen in this attempt at a solution of the Hartree-Fock problem are briefly reviewed in order to contrast with the present work.

Working memory overload: fronto-limbic interactions and effects on subsequent working memory function.

PubMed

Yun, Richard J; Krystal, John H; Mathalon, Daniel H

2010-03-01

The human working memory system provides an experimentally useful model for examination of neural overload effects on subsequent functioning of the overloaded system. This study employed functional magnetic resonance imaging in conjunction with a parametric working memory task to characterize the behavioral and neural effects of cognitive overload on subsequent cognitive performance, with particular attention to cognitive-limbic interactions. Overloading the working memory system was associated with varying degrees of subsequent decline in performance accuracy and reduced activation of brain regions central to both task performance and suppression of negative affect. The degree of performance decline was independently predicted by three separate factors operating during the overload condition: the degree of task failure, the degree of amygdala activation, and the degree of inverse coupling between the amygdala and dorsolateral prefrontal cortex. These findings suggest that vulnerability to overload effects in cognitive functioning may be mediated by reduced amygdala suppression and subsequent amygdala-prefrontal interaction.

[PSYCHO PHYSIOLOGICAL MARKERS OF ACCELERATED AGING AMONG THOSE WORKING WITH OCCUPATIONAL HAZARDS].

PubMed

Bashkireva, A S; Kachan, Ye Yu; Kulapina, M E

2015-01-01

We assessed the significance of psycho physiological markers of accelerated aging of the function of attention using comparative analysis of two occupational groups in order to reveal how the working process affects mental work capacity. We revealed peculiarities of systemic structure of functions which determine mental work capacity depending on the age and length of service in lorry drivers. It was proved that decrease in the mnestic functions of lorry-drivers takes place 10-15 years earlier compared to the control group. Psycho physiological indices, reflecting the functioning of attention, decreased not only with aging but also with longer driving experience. Our results show that it is necessary to conduct further studies of psycho physiological markers of age-related decrease in short-term memory depending on the activities at work in order to prevent accelerated aging and achieve professional longevity.

A Bioinformatics Approach to the Identification of Variants Associated with Type 1 and Type 2 Diabetes Mellitus that Reside in Functionally Validated miRNAs Binding Sites.

PubMed

Ghaedi, Hamid; Bastami, Milad; Jahani, Mohammad Mehdi; Alipoor, Behnam; Tabasinezhad, Maryam; Ghaderi, Omar; Nariman-Saleh-Fam, Ziba; Mirfakhraie, Reza; Movafagh, Abolfazl; Omrani, Mir Davood; Masotti, Andrea

2016-06-01

The present work is aimed at finding variants associated with Type 1 and Type 2 diabetes mellitus (DM) that reside in functionally validated miRNAs binding sites and that can have a functional role in determining diabetes and related pathologies. Using bioinformatics analyses we obtained a database of validated polymorphic miRNA binding sites which has been intersected with genes related to DM or to variants associated and/or in linkage disequilibrium (LD) with it and is reported in genome-wide association studies (GWAS). The workflow we followed allowed us to find variants associated with DM that also reside in functional miRNA binding sites. These data have been demonstrated to have a functional role by impairing the functions of genes implicated in biological processes linked to DM. In conclusion, our work emphasized the importance of SNPs located in miRNA binding sites. The results discussed in this work may constitute the basis of further works aimed at finding functional candidates and variants affecting protein structure and function, transcription factor binding sites, and non-coding epigenetic variants, contributing to widen the knowledge about the pathogenesis of this important disease.

Use of a structured functional evaluation process for independent medical evaluations of claimants presenting with disabling mental illness: rationale and design for a multi-center reliability study.

PubMed

Bachmann, Monica; de Boer, Wout; Schandelmaier, Stefan; Leibold, Andrea; Marelli, Renato; Jeger, Joerg; Hoffmann-Richter, Ulrike; Mager, Ralph; Schaad, Heinz; Zumbrunn, Thomas; Vogel, Nicole; Bänziger, Oskar; Busse, Jason W; Fischer, Katrin; Kunz, Regina

2016-07-29

Work capacity evaluations by independent medical experts are widely used to inform insurers whether injured or ill workers are capable of engaging in competitive employment. In many countries, evaluation processes lack a clearly structured approach, standardized instruments, and an explicit focus on claimants' functional abilities. Evaluation of subjective complaints, such as mental illness, present additional challenges in the determination of work capacity. We have therefore developed a process for functional evaluation of claimants with mental disorders which complements usual psychiatric evaluation. Here we report the design of a study to measure the reliability of our approach in determining work capacity among patients with mental illness applying for disability benefits. We will conduct a multi-center reliability study, in which 20 psychiatrists trained in our functional evaluation process will assess 30 claimants presenting with mental illness for eligibility to receive disability benefits [Reliability of Functional Evaluation in Psychiatry, RELY-study]. The functional evaluation process entails a five-step structured interview and a reporting instrument (Instrument of Functional Assessment in Psychiatry [IFAP]) to document the severity of work-related functional limitations. We will videotape all evaluations which will be viewed by three psychiatrists who will independently rate claimants' functional limitations. Our primary outcome measure is the evaluation of claimant's work capacity as a percentage (0 to 100 %), and our secondary outcomes are the 12 mental functions and 13 functional capacities assessed by the IFAP-instrument. Inter-rater reliability of four psychiatric experts will be explored using multilevel models to estimate the intraclass correlation coefficient (ICC). Additional analyses include subgroups according to mental disorder, the typicality of claimants, and claimant perceived fairness of the assessment process. We hypothesize that a structured functional approach will show moderate reliability (ICC ≥ 0.6) of psychiatric evaluation of work capacity. Enrollment of actual claimants with mental disorders referred for evaluation by disability/accident insurers will increase the external validity of our findings. Finding moderate levels of reliability, we will continue with a randomized trial to test the reliability of a structured functional approach versus evaluation-as-usual.

Cross sectional study on lung function of coke oven workers: a lung function surveillance system from 1978 to 1990

PubMed Central

Wu, J; Kreis, I; Griffiths, D; Darling, C

2002-01-01

Aims: To determine the association between lung function of coke oven workers and exposure to coke oven emissions. Methods: Lung function data and detailed work histories for workers in recovery coke ovens of a steelworks were extracted from a lung function surveillance system. Multiple regressions were employed to determine significant predictors for lung function indices. The first sets of lung function tests for 613 new starters were pooled to assess the selection bias. The last sets of lung function tests for 834 subjects with one or more year of coke oven history were pooled to assess determinants of lung function. Results: Selection bias associated with the recruitment process was not observed among the exposure groups. For subjects with a history of one or more years of coke oven work, each year of working in the most exposed "operation" position was associated with reductions in FEV1 of around 9 ml (p = 0.006, 95% CI: 3 ml to 16 ml) and in FVC of around 12 ml (p = 0.002, 95% CI: 4 ml to 19 ml). Negative effects of smoking on lung function were also observed. Conclusions: Exposure to coke oven emissions was found to be associated with lower FEV1 and FVC. Effects of work exposure on lung function are similar to those found in other studies. PMID:12468747

Development of chemically vapor deposited rhenium emitters of (0001) preferred crystal orientation

NASA Technical Reports Server (NTRS)

Yang, L.; Hudson, R. G.

1973-01-01

Rhenium thermionic emitters were prepared by the pyrolysis of rhenium chlorides formed by the chlorination of rhenium pellets. The impurity contents, microstructures, degrees of (0001) preferred crystal orientation, and vacuum electron work functions of these emitters were determined as a function of deposition parameters, such as substrate temperature, rhenium pellet temperature and chlorine flow rate. A correlation between vacuum electron work function and degree of (0001) preferred crystal orientation was established. Conditions for depositing porosity-free rhenium emitters of high vacuum electron work functions were defined. Finally, three cylindrical rhenium emitters were prepared under the optimum deposition conditions.

Early Childhood Predictors of Post-Kindergarten Executive Function: Behavior, Parent Report, and Psychophysiology

ERIC Educational Resources Information Center

Cuevas, Kimberly; Hubble, Morgan; Bell, Martha Ann

2012-01-01

Research Findings: This study examined whether children's executive functions before kindergarten would predict variance in executive functions after kindergarten. We obtained behavioral (working memory task performance), parent-reported (temperament-based inhibitory control), and psychophysiological (working memory-related changes in heart rate…

Working Memory Functions in Children with Different Degrees of Intellectual Disability

ERIC Educational Resources Information Center

Schuchardt, K.; Gebhardt, M.; Maehler, C.

2010-01-01

Background: In recent years, there has been increased research interest in the functioning of working memory in people with intellectual disabilities. Although studies have repeatedly found these individuals to have weak working memory skills, few investigations have distinguished between different degrees of intellectual disability. This study…

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

ERIC Educational Resources Information Center

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…

Working memory arrest in children with high-functioning autism compared to children with attention-deficit/hyperactivity disorder: results from a 2-year longitudinal study.

PubMed

Andersen, Per N; Skogli, Erik W; Hovik, Kjell T; Geurts, Hilde; Egeland, Jens; Øie, Merete

2015-05-01

The aim of this study was to analyse the development of verbal working memory in children with high-functioning autism compared to children with attention-deficit/hyperactivity disorder and typically developing children. A total of 34 children with high-functioning autism, 72 children with attention-deficit/hyperactivity disorder and 45 typically developing children (age 9-16 years) were included at baseline and followed up approximately 25 months later. The children were given a letter/number sequencing task to assess verbal working memory. The performance of children with high-functioning autism on verbal working memory did not improve after 2 years, while improvement was observed in children with attention-deficit/hyperactivity disorder and typically developing children. The results indicate a different developmental trajectory for verbal working memory in children with high-functioning autism compared to children with attention-deficit/hyperactivity disorder and typically developing children. More research is needed to construct a developmental framework more suitable for children with autism spectrum disorder. © The Author(s) 2014.

Influence of shift work on cognitive performance in male business process outsourcing employees

PubMed Central

Shwetha, Bijavara; Sudhakar, Honnamachanahalli

2012-01-01

Background: India is a front runner in IT industry. Business process outsourcing (BPO) sector is a major part of IT industry with around 4.5 million employees. These employees are subjected to high work stress, odd working hours, and frequent shift changes leading to increased physical and mental health problems. Aim: To study the cognitive functions in male BPO employees exposed to regular shifts. Settings and Design: Young BPO employees from various BPO companies of Bangalore were tested for cognitive functions. Materials and Methods: Fifty male BPO employees exposed to regular shifts were assessed for various cognitive functions including tests for speed, attention, learning and memory, and executive function. They were compared with 50 non-BPO employees not working in shifts. Statistical analysis - Data was analysed by t-test and Mann-Whitney test using SPSS V.13.0. Results: BPO employees performed poorly compared to their controls in tests for mental speed, learning and memory, and response inhibition. No changes were seen between groups in tests for attention and working memory. Conclusion: Cognitive functions are impaired in BPO employees exposed to regular shift changes. PMID:23776319

Influence of shift work on cognitive performance in male business process outsourcing employees.

PubMed

Shwetha, Bijavara; Sudhakar, Honnamachanahalli

2012-09-01

India is a front runner in IT industry. Business process outsourcing (BPO) sector is a major part of IT industry with around 4.5 million employees. These employees are subjected to high work stress, odd working hours, and frequent shift changes leading to increased physical and mental health problems. To study the cognitive functions in male BPO employees exposed to regular shifts. Young BPO employees from various BPO companies of Bangalore were tested for cognitive functions. Fifty male BPO employees exposed to regular shifts were assessed for various cognitive functions including tests for speed, attention, learning and memory, and executive function. They were compared with 50 non-BPO employees not working in shifts. Statistical analysis - Data was analysed by t-test and Mann-Whitney test using SPSS V.13.0. BPO employees performed poorly compared to their controls in tests for mental speed, learning and memory, and response inhibition. No changes were seen between groups in tests for attention and working memory. Cognitive functions are impaired in BPO employees exposed to regular shift changes.

Effective work function engineering for a TiN/XO(X = La, Zr, Al)/SiO{sub 2} stack structures

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

Lee, Dongjin, E-mail: dongjin0710.lee@samsung.com; Lee, Jieun; Jung, Kyoungho

In this study, we demonstrated that work function engineering is possible over a wide range (+200 mV to −430 mV) in a TiN/XO (X = La, Zr, or Al)/SiO{sub 2} stack structures. From ab initio simulations, we selected the optimal material for the work function engineering. The work function engineering mechanism was described by metal diffusion into the TiN film and silicate formation in the TiN/SiO{sub 2} interface. The metal doping and the silicate formation were confirmed by transmission electron microscopy and energy dispersive spectroscopy line profiling, respectively. In addition, the amount of doped metal in the TiN film depended on the thickness ofmore » the insertion layer XO. From the work function engineering technique, which can control a variety of threshold voltages (Vth), an improvement in transistors with different V{sub th} values in the TiN/XO/SiO{sub 2} stack structures is expected.« less

Modulation of steady state functional connectivity in the default mode and working memory networks by cognitive load.

PubMed

Newton, Allen T; Morgan, Victoria L; Rogers, Baxter P; Gore, John C

2011-10-01

Interregional correlations between blood oxygen level dependent (BOLD) magnetic resonance imaging (fMRI) signals in the resting state have been interpreted as measures of connectivity across the brain. Here we investigate whether such connectivity in the working memory and default mode networks is modulated by changes in cognitive load. Functional connectivity was measured in a steady-state verbal identity N-back task for three different conditions (N = 1, 2, and 3) as well as in the resting state. We found that as cognitive load increases, the functional connectivity within both the working memory the default mode network increases. To test whether functional connectivity between the working memory and the default mode networks changed, we constructed maps of functional connectivity to the working memory network as a whole and found that increasingly negative correlations emerged in a dorsal region of the posterior cingulate cortex. These results provide further evidence that low frequency fluctuations in BOLD signals reflect variations in neural activity and suggests interaction between the default mode network and other cognitive networks. Copyright © 2010 Wiley-Liss, Inc.

Verbal working memory-related functional connectivity alterations in boys with attention-deficit/hyperactivity disorder and the effects of methylphenidate.

PubMed

Wu, Zhao-Min; Bralten, Janita; An, Li; Cao, Qing-Jiu; Cao, Xiao-Hua; Sun, Li; Liu, Lu; Yang, Li; Mennes, Maarten; Zang, Yu-Feng; Franke, Barbara; Hoogman, Martine; Wang, Yu-Feng

2017-08-01

Few studies have investigated verbal working memory-related functional connectivity patterns in participants with attention-deficit/hyperactivity disorder (ADHD). Thus, we aimed to compare working memory-related functional connectivity patterns in healthy children and those with ADHD, and study effects of methylphenidate (MPH). Twenty-two boys with ADHD were scanned twice, under either MPH (single dose, 10 mg) or placebo, in a randomised, cross-over, counterbalanced placebo-controlled design. Thirty healthy boys were scanned once. We used fMRI during a numerical n-back task to examine functional connectivity patterns in case-control and MPH-placebo comparisons, using independent component analysis. There was no significant difference in behavioural performance between children with ADHD, treated with MPH or placebo, and healthy controls. Compared with controls, participants with ADHD under placebo showed increased functional connectivity within fronto-parietal and auditory networks, and decreased functional connectivity within the executive control network. MPH normalized the altered functional connectivity pattern and significantly enhanced functional connectivity within the executive control network, though in non-overlapping areas. Our study contributes to the identification of the neural substrates of working memory. Single dose of MPH normalized the altered brain functional connectivity network, but had no enhancing effect on (non-impaired) behavioural performance.

Neural Correlates of Working Memory Performance in Adolescents and Young Adults with Dyslexia

ERIC Educational Resources Information Center

Vasic, Nenad; Lohr, Christina; Steinbrink, Claudia; Martin, Claudia; Wolf, Robert Christian

2008-01-01

Behavioral studies indicate deficits in phonological working memory (WM) and executive functioning in dyslexics. However, little is known about the underlying functional neuroanatomy. In the present study, neural correlates of WM in adolescents and young adults with dyslexia were investigated using event-related functional magnetic resonance…

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

PubMed

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/.

Mnemonic function in small vessel disease and associations with white matter tract microstructure.

PubMed

Metoki, Athanasia; Brookes, Rebecca L; Zeestraten, Eva; Lawrence, Andrew J; Morris, Robin G; Barrick, Thomas R; Markus, Hugh S; Charlton, Rebecca A

2017-09-01

Cerebral small vessel disease (SVD) is associated with deficits in working memory, with a relative sparing of long-term memory; function may be influenced by white matter microstructure. Working and long-term memory were examined in 106 patients with SVD and 35 healthy controls. Microstructure was measured in the uncinate fasciculi and cingula. Working memory was more impaired than long-term memory in SVD, but both abilities were reduced compared to controls. Regression analyses found that having SVD explained the variance in memory functions, with additional variance explained by the cingula (working memory) and uncinate (long-term memory). Performance can be explained in terms of integrity loss in specific white matter tract associated with mnemonic functions. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Recommended values of clean metal surface work functions

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

Derry, Gregory N., E-mail: gderry@loyola.edu; Kern, Megan E.; Worth, Eli H.

2015-11-15

A critical review of the experimental literature for measurements of the work functions of clean metal surfaces of single-crystals is presented. The tables presented include all results found for low-index crystal faces except cases that were known to be contaminated surfaces. These results are used to construct a recommended value of the work function for each surface examined, along with an uncertainty estimate for that value. The uncertainties are based in part on the error distribution for all measured work functions in the literature, which is included here. The metals included in this review are silver (Ag), aluminum (Al), goldmore » (Au), copper (Cu), iron (Fe), iridium (Ir), molybdenum (Mo), niobium (Nb), nickel (Ni), palladium (Pd), platinum (Pt), rhodium (Rh), ruthenium (Ru), tantalum (Ta), and tungsten (W)« less

A dual change model of life satisfaction and functioning for individuals with schizophrenia

PubMed Central

Edmondson, Melissa; Pahwa, Rohini; Lee, Karen Kyeunghae; Hoe, Maanse; Brekke, John S.

2013-01-01

Despite the notion that increases in functioning should be associated with increases in life satisfaction in schizophrenia, research has often found no association between the two. Dual change models of global and domain-specific life satisfaction and functioning were examined in 145 individuals with schizophrenia receiving community-based services over 12 months. Functioning and satisfaction were measured using the Role Functioning Scale and Satisfaction with Life Scale. Data were analyzed using latent growth curve modeling. Improvement in global life satisfaction was associated with improvement in overall functioning over time. Satisfaction with living situation also improved as independent functioning improved. Work satisfaction did not improve as work functioning improved. Although social functioning improved, satisfaction with social relationships did not. The link between overall functioning and global life satisfaction provides support for a recovery-based orientation to community based psychosocial rehabilitation services. When examining sub-domains, the link between outcomes and subjective experience suggests a more complex picture than previously found. These findings are crucial to interventions and programs aimed at improving functioning and the subjective experiences of consumers recovering from mental illness. Interventions that show improvements in functional outcomes can assume that they will show concurrent improvements in global life satisfaction as well and in satisfaction with independent living. Interventions geared toward improving social functioning will need to consider the complexity of social relationships and how they affect satisfaction associated with personal relationships. Interventions geared towards improving work functioning will need to consider how the quality and level of work affect satisfaction with employment. PMID:22591780

Novelty modulates human striatal activation and prefrontal-striatal effective connectivity during working memory encoding.

PubMed

Geiger, Lena S; Moessnang, Carolin; Schäfer, Axel; Zang, Zhenxiang; Zangl, Maria; Cao, Hengyi; van Raalten, Tamar R; Meyer-Lindenberg, Andreas; Tost, Heike

2018-05-11

The functional role of the basal ganglia (BG) in the gating of suitable motor responses to the cortex is well established. Growing evidence supports an analogous role of the BG during working memory encoding, a task phase in which the "input-gating" of relevant materials (or filtering of irrelevant information) is an important mechanism supporting cognitive capacity and the updating of working memory buffers. One important aspect of stimulus relevance is the novelty of working memory items, a quality that is understudied with respect to its effects on corticostriatal function and connectivity. To this end, we used functional magnetic resonance imaging (fMRI) in 74 healthy volunteers performing an established Sternberg working memory task with different task phases (encoding vs. retrieval) and degrees of stimulus familiarity (novel vs. previously trained). Activation analyses demonstrated a highly significant engagement of the anterior striatum, in particular during the encoding of novel working memory items. Dynamic causal modeling (DCM) of corticostriatal circuit connectivity identified a selective positive modulatory influence of novelty encoding on the connection from the dorsolateral prefrontal cortex (DLPFC) to the anterior striatum. These data extend prior research by further underscoring the relevance of the BG for human cognitive function and provide a mechanistic account of the DLPFC as a plausible top-down regulatory element of striatal function that may facilitate the "input-gating" of novel working memory materials.

Diagnostic Accuracy of the Work Functioning Impairment Scale (WFun): A Method to Detect Workers Who Have Health Problems Affecting their Work and to Evaluate Fitness for Work.

PubMed

Nagata, Tomohisa; Fujino, Yoshihisa; Saito, Kumi; Uehara, Masamichi; Oyama, Ichiro; Izumi, Hiroyuki; Kubo, Tatsuhiko

2017-06-01

This study evaluated the diagnostic accuracy of the Work Functioning Impairment Scale (WFun), a questionnaire to detect workers with health problems which affect their work, using an assessment by an occupational health nurse as objective standard. The WFun was completed by 294 employees. The nurse interviewed to assess 1) health problems; 2) effects of health on their work; necessity for 3) treatment, 4) health care instruction, and 5) consideration of job accommodation. The odds ratio in the high work functioning impairment group compared with the low was highly statistically significant with 9.05, 10.26, 5.77, 9.37, and 14.70, respectively. The WFun demonstrated the high detectability with an area under the receiver operating characteristic of 0.75, 0.81, 0.72, 0.79, and 0.83, respectively. This study suggests that the WFun is useful in detecting those who have health problems affecting their work.

Method of making low work function component

DOEpatents

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.

Work function of few layer graphene covered nickel thin films measured with Kelvin probe force microscopy

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

Eren, B.; Material Sciences Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, California 94720; Gysin, U.

2016-01-25

Few layer graphene and graphite are simultaneously grown on a ∼100 nm thick polycrystalline nickel film. The work function of few layer graphene/Ni is found to be 4.15 eV with a variation of 50 meV by local measurements with Kelvin probe force microscopy. This value is lower than the work function of free standing graphene due to peculiar electronic structure resulting from metal 3d-carbon 2p(π) hybridization.

[Changes in quality of life and work function during phase prophylactic lamotrigine treatment in bipolar patients: 6 month, prospective, observational study].

PubMed

Gonda, Xenia; Kalman, Janos; Dome, Peter; Rihmer, Zoltan

2016-03-01

Bipolar disorder is a lifelong illness requiring lifelong pharmacotherapy. Therefore besides symptomatic remission, achievement of full work-related functioning and restoration of quality of life is a priority during successful treatment. The present prospective, observational, non-intervention study focused on investigating the effect of lamotrigine therapy on the quality of life and work-related function of bipolar patients in outpatient care. 969 bipolar or schizoaffective outpatients participated in the study who previously did not receive lamotrigine therapy. Our present phase-prophylactic study was a prospective, observational, non-intervention study with a six-month follow-up. Evaluations took place at baseline and at months 1, 2, 3 and 6. Patients were followed with a Clinical Global Impression-Severity (CGI-S) and Clinical Global Impression-Improvement (CGI-I). Changes in work-related function was evaluated using Social Adjustment Scale (SAS), while quality of life was assessed with the Quality of Life Enjoyment and Satisfaction Questionnaire (Q-LES-Q) scale. SAS scoreds showed a consistent decrease in the overall sample and in all CGI-S initial groups reflecting the improvement of work-related function during the six months of the follow-up. Q-LES-Q values in the whole sample and in all initial CGI-S groups showed a steady increase indicating a continuous increase in quality of life during the study. Our results indicate that during long-term prophylactic lamotrigine therapy the work function and quality of life of bipolar patients shows a significant improvement, therefore lamotrigine provides a possibility for full functional remission and restoration of quality of life.

Executive functioning and reading achievement in school: a study of Brazilian children assessed by their teachers as "poor readers".

PubMed

Engel de Abreu, Pascale M J; Abreu, Neander; Nikaedo, Carolina C; Puglisi, Marina L; Tourinho, Carlos J; Miranda, Mônica C; Befi-Lopes, Debora M; Bueno, Orlando F A; Martin, Romain

2014-01-01

This study examined executive functioning and reading achievement in 106 6- to 8-year-old Brazilian children from a range of social backgrounds of whom approximately half lived below the poverty line. A particular focus was to explore the executive function profile of children whose classroom reading performance was judged below standard by their teachers and who were matched to controls on chronological age, sex, school type (private or public), domicile (Salvador/BA or São Paulo/SP) and socioeconomic status. Children completed a battery of 12 executive function tasks that were conceptual tapping cognitive flexibility, working memory, inhibition and selective attention. Each executive function domain was assessed by several tasks. Principal component analysis extracted four factors that were labeled "Working Memory/Cognitive Flexibility," "Interference Suppression," "Selective Attention," and "Response Inhibition." Individual differences in executive functioning components made differential contributions to early reading achievement. The Working Memory/Cognitive Flexibility factor emerged as the best predictor of reading. Group comparisons on computed factor scores showed that struggling readers displayed limitations in Working Memory/Cognitive Flexibility, but not in other executive function components, compared to more skilled readers. These results validate the account that working memory capacity provides a crucial building block for the development of early literacy skills and extends it to a population of early readers of Portuguese from Brazil. The study suggests that deficits in working memory/cognitive flexibility might represent one contributing factor to reading difficulties in early readers. This might have important implications for how educators might intervene with children at risk of academic under achievement.

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

PubMed

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.

Low-power DRAM-compatible Replacement Gate High-k/Metal Gate Stacks

NASA Astrophysics Data System (ADS)

Ritzenthaler, R.; Schram, T.; Bury, E.; Spessot, A.; Caillat, C.; Srividya, V.; Sebaai, F.; Mitard, J.; Ragnarsson, L.-Å.; Groeseneken, G.; Horiguchi, N.; Fazan, P.; Thean, A.

2013-06-01

In this work, the possibility of integration of High-k/Metal Gate (HKMG), Replacement Metal Gate (RMG) gate stacks for low power DRAM compatible transistors is studied. First, it is shown that RMG gate stacks used for Logic applications need to be seriously reconsidered, because of the additional anneal(s) needed in a DRAM process. New solutions are therefore developed. A PMOS stack HfO2/TiN with TiN deposited in three times combined with Work Function metal oxidations is demonstrated, featuring a very good Work Function of 4.95 eV. On the other hand, the NMOS side is shown to be a thornier problem to solve: a new solution based on the use of oxidized Ta as a diffusion barrier is proposed, and a HfO2/TiN/TaOX/TiAl/TiN/TiN gate stack featuring an aggressive Work Function of 4.35 eV (allowing a Work Function separation of 600 mV between NMOS and PMOS) is demonstrated. This work paves the way toward the integration of gate-last options for DRAM periphery transistors.

Work Characteristics Associated with Physical Functioning in Women

PubMed Central

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

2017-01-01

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 <25th percentile, was examined using modified Poisson regression. After controlling for confounding variables, high physical demand was positively associated with physical limitations (RR = 1.09 CI: 1.06–1.12) and substantively complex work was negatively associated (RR = 0.94, CI: 0.91–0.96). Jobs requiring complex problem solving, active learning, and 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. PMID:28420131

High-work-function molybdenum oxide hole extraction contacts in hybrid organic–inorganic perovskite solar cells

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

Schulz, Philip; Tiepelt, Jan O.; Christians, Jeffrey A.

2016-11-08

Here, we investigate the effect of high work function contacts in halide perovskite absorber-based photovoltaic devices. Photoemission spectroscopy measurements reveal that band bending is induced in the absorber by the deposition of the high work function molybdenum trioxide (MoO 3). We find that direct contact between MoO 3 and the perovskite leads to a chemical reaction, which diminishes device functionality. Introducing an ultrathin spiro-MeOTAD buffer layer prevents the reaction, yet the altered evolution of the energy levels in the methylammonium lead iodide (MAPbI 3) layer at the interface still negatively impacts device performance.

Scheduling on the basis of the research of dependences among the construction process parameters

NASA Astrophysics Data System (ADS)

Romanovich, Marina; Ermakov, Alexander; Mukhamedzhanova, Olga

2017-10-01

The dependences among the construction process parameters are investigated in the article: average integrated value of qualification of the shift, number of workers per shift and average daily amount of completed work on the basis of correlation coefficient are considered. Basic data for the research of dependences among the above-stated parameters have been collected during the construction of two standard objects A and B (monolithic houses), in four months of construction (October, November, December, January). Kobb-Douglas production function has proved the values of coefficients of correlation close to 1. Function is simple to be used and is ideal for the description of the considered dependences. The development function, describing communication among the considered parameters of the construction process, is developed. The function of the development gives the chance to select optimum quantitative and qualitative (qualification) structure of the brigade link for the work during the next period of time, according to a preset value of amount of works. Function of the optimized amounts of works, which reflects interrelation of key parameters of construction process, is developed. Values of function of the optimized amounts of works should be used as the average standard for scheduling of the storming periods of construction.

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

NASA Astrophysics Data System (ADS)

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.

Occipital cortex of blind individuals is functionally coupled with executive control areas of frontal cortex.

PubMed

Deen, Ben; Saxe, Rebecca; Bedny, Marina

2015-08-01

In congenital blindness, the occipital cortex responds to a range of nonvisual inputs, including tactile, auditory, and linguistic stimuli. Are these changes in functional responses to stimuli accompanied by altered interactions with nonvisual functional networks? To answer this question, we introduce a data-driven method that searches across cortex for functional connectivity differences across groups. Replicating prior work, we find increased fronto-occipital functional connectivity in congenitally blind relative to blindfolded sighted participants. We demonstrate that this heightened connectivity extends over most of occipital cortex but is specific to a subset of regions in the inferior, dorsal, and medial frontal lobe. To assess the functional profile of these frontal areas, we used an n-back working memory task and a sentence comprehension task. We find that, among prefrontal areas with overconnectivity to occipital cortex, one left inferior frontal region responds to language over music. By contrast, the majority of these regions responded to working memory load but not language. These results suggest that in blindness occipital cortex interacts more with working memory systems and raise new questions about the function and mechanism of occipital plasticity.

20 CFR 220.178 - Determining medical improvement and its relationship to the annuitant's ability to do work.

Code of Federal Regulations, 2011 CFR

2011-04-01

... § 220.177(d) the relationship between medical severity and limitation on functional capacity to do basic work activities (or residual functional capacity) and how changes in medical severity can affect the annuitant's residual functional capacity is explained. In determining whether medical improvement that has...

Insights from Cognitive Neuroscience: The Importance of Executive Function for Early Reading Development and Education

ERIC Educational Resources Information Center

Cartwright, Kelly B.

2012-01-01

Research Findings: Executive function begins to develop in infancy and involves an array of processes, such as attention, inhibition, working memory, and cognitive flexibility, which provide the means by which individuals control their own behavior, work toward goals, and manage complex cognitive processes. Thus, executive function plays a…

Training and Transfer Effects of Executive Functions in Preschool Children

ERIC Educational Resources Information Center

Thorell, Lisa B.; Lindqvist, Sofia; Nutley, Sissela Bergman; Bohlin, Gunilla; Klingberg, Torkel

2009-01-01

Executive functions, including working memory and inhibition, are of central importance to much of human behavior. Interventions intended to improve executive functions might therefore serve an important purpose. Previous studies show that working memory can be improved by training, but it is unknown if this also holds for inhibition, and whether…

Maternal IL-6 during pregnancy can be estimated from newborn brain connectivity and predicts future working memory in offspring.

PubMed

Rudolph, Marc D; Graham, Alice M; Feczko, Eric; Miranda-Dominguez, Oscar; Rasmussen, Jerod M; Nardos, Rahel; Entringer, Sonja; Wadhwa, Pathik D; Buss, Claudia; Fair, Damien A

2018-05-01

Several lines of evidence support the link between maternal inflammation during pregnancy and increased likelihood of neurodevelopmental and psychiatric disorders in offspring. This longitudinal study seeks to advance understanding regarding implications of systemic maternal inflammation during pregnancy, indexed by plasma interleukin-6 (IL-6) concentrations, for large-scale brain system development and emerging executive function skills in offspring. We assessed maternal IL-6 during pregnancy, functional magnetic resonance imaging acquired in neonates, and working memory (an important component of executive function) at 2 years of age. Functional connectivity within and between multiple neonatal brain networks can be modeled to estimate maternal IL-6 concentrations during pregnancy. Brain regions heavily weighted in these models overlap substantially with those supporting working memory in a large meta-analysis. Maternal IL-6 also directly accounts for a portion of the variance of working memory at 2 years of age. Findings highlight the association of maternal inflammation during pregnancy with the developing functional architecture of the brain and emerging executive function.

The Effects of Acute Stress on Core Executive Functions: A Meta-Analysis and Comparison with Cortisol

PubMed Central

Shields, Grant S.; Sazma, Matthew A.; Yonelinas, Andrew P.

2016-01-01

Core executive functions such as working memory, inhibition, and cognitive flexibility are integral to daily life. A growing body of research has suggested that acute stress may impair core executive functions. However, there are a number of inconsistencies in the literature, leading to uncertainty about how or even if acute stress influences core executive functions. We addressed this by conducting a meta-analysis of acute stress effects on working memory, inhibition, and cognitive flexibility. We found that stress impaired working memory and cognitive flexibility, whereas it had nuanced effects on inhibition. Many of these effects were moderated by other variables, such as sex. In addition, we compared effects of acute stress on core executive functions to effects of cortisol administration and found some striking differences. Our findings indicate that stress works through mechanisms aside from or in addition to cortisol to produce a state characterized by more reactive processing of salient stimuli but greater control over actions. We conclude by highlighting some important future directions for stress and executive function research. PMID:27371161

The impact of bilingualism on working memory in pediatric epilepsy

PubMed Central

Veenstra, Amy L.; Riley, Jeffrey D.; Barrett, Lauren E.; Muhonen, Michael G.; Zupanc, Mary; Romain, Jonathan E.; Lin, Jack J.; Mucci, Grace

2016-01-01

Impairments in executive skills broadly span across multiple childhood epilepsy syndromes and can adversely affect quality of life. Bilingualism has been previously shown to correlate with enhanced executive functioning in healthy individuals. This study seeks to determine whether the bilingual advantage in executive functioning exists in the context of pediatric epilepsy. We retrospectively analyzed neuropsychological data in 52 children with epilepsy and compared executive function scores in monolingual versus bilingual children with epilepsy, while controlling for socioeconomic status and ethnicity. Bilingual children performed significantly better on the Working Memory scale than did monolingual children. There were no significant differences on the remaining executive function variables. The bilingual advantage appears to persist for working memory in children with epilepsy. These findings suggest that bilingualism is potentially a protective variable in the face of epilepsy-related working memory dysfunction. PMID:26720703

Systems and methods for producing low work function electrodes

DOEpatents

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.

Secondary ion generation mechanism studied by ISS-SIMS and work function measurements

NASA Astrophysics Data System (ADS)

Kawatoh, Eizoh; Terada, Norihito; Shimizu, Ryuichi; Kang, Hee Jae

1989-03-01

Oxygen enhancement effects in secondary ion generation were studied in polycrystalline Ni at different partial pressures of oxygen, Po2, by sequential ISS-SIMS and work function measurements. The investigation has revealed that the enhancement undergoes three stages: (I) The secondary ion intensity increases monotonically with an increase of work function which is described very well by the electron tunneling model. (II) This tendency abruptly changes, i.e. the work function decreases and the secondary ion intensity increases rapidly, for a slight increase of Po2 (III) The secondary ion intensities gradually increase and become saturated with a further increase of Po2. It has also been found that the critical coverage, θc, corresponds exactly to the stage (II) behaviour, which was observed by Blaise and Bernheim for a single crystal (100)Ni surface.

Quantitative secondary electron imaging for work function extraction at atomic level and layer identification of graphene

PubMed Central

Zhou, Yangbo; Fox, Daniel S; Maguire, Pierce; O’Connell, Robert; Masters, Robert; Rodenburg, Cornelia; Wu, Hanchun; Dapor, Maurizio; Chen, Ying; Zhang, Hongzhou

2016-01-01

Two-dimensional (2D) materials usually have a layer-dependent work function, which require fast and accurate detection for the evaluation of their device performance. A detection technique with high throughput and high spatial resolution has not yet been explored. Using a scanning electron microscope, we have developed and implemented a quantitative analytical technique which allows effective extraction of the work function of graphene. This technique uses the secondary electron contrast and has nanometre-resolved layer information. The measurement of few-layer graphene flakes shows the variation of work function between graphene layers with a precision of less than 10 meV. It is expected that this technique will prove extremely useful for researchers in a broad range of fields due to its revolutionary throughput and accuracy. PMID:26878907

Prospective Cohort Study of Work Functioning Impairment and Subsequent Absenteeism Among Japanese Workers.

PubMed

Fujino, Yoshihisa; Shazuki, Shuichiro; Izumi, Hiroyuki; Uehara, Masamichi; Muramatsu, Keiji; Kubo, Tatsuhiko; Oyama, Ichiro; Matsuda, Shinya

2016-07-01

This study examined the association of work functioning impairment as measured by work functioning impairment scale (WFun) and subsequent sick leave. A prospective cohort study was conducted at a manufacturer in Japan, and 1263 employees participated. Information on sick leave was gathered during an 18-month follow-up period. The hazard ratios (HRs) of long-term sick leave were substantially increased for those with a WFun score greater than 25 (HR = 3.99, P = 0.003). The incidence rate ratios (IRRs) of days of short-term absence gradually increased as scores of WFun increased (IRR = 1.18, P < 0.001 in the subjects with WFun of over 25 comparing with those with WFun of 14 or less). Assessing work functioning impairment is a useful way of classifying risk for future sick leave among employees.

Improved clinical, functional and work outcomes in spondyloarthritides during real-life adalimumab treatment in central-eastern Europe.

PubMed

Szántó, Sándor; Poór, Gyula; Opris, Daniela; Iaremenko, Oleg; Procházková, Leona; Kuuse, Reet; Nagy, Orsolya; Chernyshov, Valentyn; Géher, Pál

2016-08-01

Adalimumab effectiveness on clinical, functional and work-related outcomes was evaluated in patients with active ankylosing spondylitis or psoriatic arthritis treated in routine clinical practice in central-eastern Europe. Patients (n = 555) were followed for 12 months. Primary end point was percentage of patients with a treatment response (≥50% decrease from baseline in Bath Ankylosing Spondylitis Disease Activity Index or ≥1.2 point decrease from baseline in Disease Activity Index-28 joint for axial or peripheral symptoms, respectively). Functional status was evaluated by the Bath Ankylosing Spondylitis Functional Index and Health Assessment Questionnaire Disability Index. Working ability was evaluated by the Work Productivity and Activity Impairment Questionnaire - Specific Health Problem. 76.1% of patients with axial symptoms and 83.5% with peripheral symptoms achieved a treatment response. Frequency of extra-articular manifestations decreased. Improvements were observed in functional status and workability. No new safety signals were observed. Adalimumab was effective and well tolerated during real-world use in central-eastern Europe.

A heuristic neural network initialization scheme for modeling nonlinear functions in engineering mechanics: continuous development

NASA Astrophysics Data System (ADS)

Pei, Jin-Song; Mai, Eric C.

2007-04-01

This paper introduces a continuous effort towards the development of a heuristic initialization methodology for constructing multilayer feedforward neural networks to model nonlinear functions. In this and previous studies that this work is built upon, including the one presented at SPIE 2006, the authors do not presume to provide a universal method to approximate arbitrary functions, rather the focus is given to the development of a rational and unambiguous initialization procedure that applies to the approximation of nonlinear functions in the specific domain of engineering mechanics. The applications of this exploratory work can be numerous including those associated with potential correlation and interpretation of the inner workings of neural networks, such as damage detection. The goal of this study is fulfilled by utilizing the governing physics and mathematics of nonlinear functions and the strength of the sigmoidal basis function. A step-by-step graphical procedure utilizing a few neural network prototypes as "templates" to approximate commonly seen memoryless nonlinear functions of one or two variables is further developed in this study. Decomposition of complex nonlinear functions into a summation of some simpler nonlinear functions is utilized to exploit this prototype-based initialization methodology. Training examples are presented to demonstrate the rationality and effciency of the proposed methodology when compared with the popular Nguyen-Widrow initialization algorithm. Future work is also identfied.

Pulmonary functions in plastic factory workers: a preliminary study.

PubMed

Khaliq, Farah; Singh, Pawan; Chandra, Prakash; Gupta, Keshav; Vaney, Neelam

2011-01-01

Exposure to long term air pollution in the work environment may result in decreased lung functions and various other health problems. A significant occupational hazard to lung functions is experienced by plastic factory workers. The present study is planned to assess the pulmonary functions of workers in the plastic factory where recycling of pastic material was done. These workers were constantly exposed to fumes of various chemicals throughout the day. Thirty one workers of plastic factory were assessed for their pulmonary functions. Parameters were compared with 31 age and sex matched controls not exposed to the same environment. The pulmonary function tests were done using Sibelmed Datospir 120 B portable spirometer. A significant decrease in most of the flow rates (MEF 25%, MEF 50%, MEF 75% and FEF 25-75%) and most of the lung volumes and capacities (FVC, FEV1, VC, TV, ERV, MVV) were observed in the workers. Smoking and duration of exposure were not affecting the lung functions as the non smokers also showed a similar decrement in pulmonary functions. Similarly the workers working for less than 5 years also had decrement in pulmonary functions indicating that their lungs are being affected even if they have worked for one year. Exposure to the organic dust in the work environment should be controlled by adequate engineering measures, complemented by effective personal respiratory protection.

Domains of cognitive function in early old age: which ones are predicted by pre-retirement psychosocial work characteristics?

PubMed Central

Sabbath, Erika; Andel, Ross; Zins, Marie; Goldberg, Marcel; Berr, Claudine

2016-01-01

Background Psychosocial work characteristics may predict cognitive functioning after retirement. However, little research has explored specific cognitive domains associated with psychosocial work environments. Our study tested whether exposure to job demands, job control, and their combination during working life predicted post-retirement performance on eight cognitive tests. Methods We used data from French GAZEL cohort members who had undergone post-retirement cognitive testing (n=2,149). Psychosocial job characteristics were measured on average four years before retirement using Karasek’s Job Content Questionnaire (job demands, job control, demand-control combinations). We tested associations between these exposures and post-retirement performance on tests of executive function, visual-motor speed, psycho-motor speed, verbal memory, and verbal fluency using OLS regression. Results Low job control during working life was negatively associated with executive function, psychomotor speed, phonemic fluency, and semantic fluency after retirement (p’s<.05) even after adjustment for demographics, socioeconomic status, health and social behaviours, and vascular risk factors. Both passive (low-demand, low-control) and high-strain (high-demand, low-control) jobs were associated with lower scores on phonemic and semantic fluency when compared to low-strain (low-demand, high-control) jobs. Conclusions Low job control, in combination with both high and low job demands, is associated with post-retirement deficits in some, but not all, cognitive domains. In addition to work stress, associations between passive work and subsequent cognitive function may implicate lack of cognitive engagement at work as a risk factor for future cognitive difficulties. PMID:27188277

Causal Evidence from Humans for the Role of Mediodorsal Nucleus of the Thalamus in Working Memory.

PubMed

Peräkylä, Jari; Sun, Lihua; Lehtimäki, Kai; Peltola, Jukka; Öhman, Juha; Möttönen, Timo; Ogawa, Keith H; Hartikainen, Kaisa M

2017-12-01

The mediodorsal nucleus of the thalamus (MD), with its extensive connections to the lateral pFC, has been implicated in human working memory and executive functions. However, this understanding is based solely on indirect evidence from human lesion and imaging studies and animal studies. Direct, causal evidence from humans is missing. To obtain direct evidence for MD's role in humans, we studied patients treated with deep brain stimulation (DBS) for refractory epilepsy. This treatment is thought to prevent the generalization of a seizure by disrupting the functioning of the patient's anterior nuclei of the thalamus (ANT) with high-frequency electric stimulation. This structure is located superior and anterior to MD, and when the DBS lead is implanted in ANT, tip contacts of the lead typically penetrate through ANT into the adjoining MD. To study the role of MD in human executive functions and working memory, we periodically disrupted and recovered MD's function with high-frequency electric stimulation using DBS contacts reaching MD while participants performed a cognitive task engaging several aspects of executive functions. We hypothesized that the efficacy of executive functions, specifically working memory, is impaired when the functioning of MD is perturbed by high-frequency stimulation. Eight participants treated with ANT-DBS for refractory epilepsy performed a computer-based test of executive functions while DBS was repeatedly switched ON and OFF at MD and at the control location (ANT). In comparison to stimulation of the control location, when MD was stimulated, participants committed 2.26 times more errors in general (total errors; OR = 2.26, 95% CI [1.69, 3.01]) and 2.86 times more working memory-related errors specifically (incorrect button presses; OR = 2.88, CI [1.95, 4.24]). Similarly, participants committed 1.81 more errors in general ( OR = 1.81, CI [1.45, 2.24]) and 2.08 times more working memory-related errors ( OR = 2.08, CI [1.57, 2.75]) in comparison to no stimulation condition. "Total errors" is a composite score consisting of basic error types and was mostly driven by working memory-related errors. The facts that MD and a control location, ANT, are only few millimeters away from each other and that their stimulation produces very different results highlight the location-specific effect of DBS rather than regionally unspecific general effect. In conclusion, disrupting and recovering MD's function with high-frequency electric stimulation modulated participants' online working memory performance providing causal, in vivo evidence from humans for the role of MD in human working memory.

The Structure of Working Memory from 4 to 15 Years of Age

ERIC Educational Resources Information Center

Gathercole, Susan E.; Pickering, Susan J.; Ambridge, Benjamin; Wearing, Hannah

2004-01-01

The structure of working memory and its development across the childhood years were investigated in children 4-15 years of age. The children were given multiple assessments of each component of the A. D. Baddeley and G. Hitch (1974) working memory model. Broadly similar linear functions characterized performance on all measures as a function of…

Gestures, but Not Meaningless Movements, Lighten Working Memory Load when Explaining Math

ERIC Educational Resources Information Center

Cook, Susan Wagner; Yip, Terina Kuangyi; Goldin-Meadow, Susan

2012-01-01

Gesturing is ubiquitous in communication and serves an important function for listeners, who are able to glean meaningful information from the gestures they see. But gesturing also functions for speakers, whose own gestures reduce demands on their working memory. Here we ask whether gesture's beneficial effects on working memory stem from its…

Study of low resistivity and high work function ITO films prepared by oxygen flow rates and N2O plasma treatment for amorphous/crystalline silicon heterojunction solar cells.

PubMed

Hussain, Shahzada Qamar; Oh, Woong-Kyo; Kim, Sunbo; Ahn, Shihyun; Le, Anh Huy Tuan; Park, Hyeongsik; Lee, Youngseok; Dao, Vinh Ai; Velumani, S; Yi, Junsin

2014-12-01

Pulsed DC magnetron sputtered indium tin oxide (ITO) films deposited on glass substrates with lowest resistivity of 2.62 x 10(-4) Ω x cm and high transmittance of about 89% in the visible wavelength region. We report the enhancement of ITO work function (Φ(ITO)) by the variation of oxygen (O2) flow rate and N2O surface plasma treatment. The Φ(ITO) increased from 4.43 to 4.56 eV with the increase in O2 flow rate from 0 to 4 sccm while surface treatment of N2O plasma further enhanced the ITO work function to 4.65 eV. The crystallinity of the ITO films improved with increasing O2 flow rate, as revealed by XRD analysis. The ITO work function was increased by the interfacial dipole resulting from the surface rich in O- ions and by the dipole moment formed at the ITO surface during N2O plasma treatment. The ITO films with high work functions can be used to modify the front barrier height in heterojunction with intrinsic thin layer (HIT) solar cells.

Sensing the facet orientation in silver nano-plates using scanning Kelvin probe microscopy in air

NASA Astrophysics Data System (ADS)

Abdellatif, M. H.; Salerno, M.; Polovitsyn, Anatolii; Marras, Sergio; De Angelis, Francesco

2017-05-01

The work function of nano-materials is important for a full characterization of their electronic properties. Because the band alignment, band bending and electronic noise are very sensitive to work function fluctuations, the dependence of the work function of nano-scale crystals on facet orientation can be a critical issue in optimizing optoelectronic devices based on these materials. We used scanning Kelvin probe microscopy to assess the local work function on samples of silver nano-plates at sub-micrometric spatial resolution. With the appropriate choice of the substrate and based on statistical analysis, it was possible to distinguish the surface potential of the different facets of silver nano-plates even if the measurements were done in ambient conditions without the use of vacuum. A phenomenological model was used to calculate the differences of facet work function of the silver nano-plates and the corresponding shift in Fermi level. This theoretical prediction and the experimentally observed difference in surface potential on the silver nano-plates were in good agreement. Our results show the possibility to sense the nano-crystal facets by appropriate choice of the substrate in ambient conditions.

Dissociation of working memory impairments and attention-deficit/hyperactivity disorder in the brain.

PubMed

Mattfeld, Aaron T; Whitfield-Gabrieli, Susan; Biederman, Joseph; Spencer, Thomas; Brown, Ariel; Fried, Ronna; Gabrieli, John D E

2016-01-01

Prevailing neuropsychological models of attention-deficit/hyperactivity disorder (ADHD) propose that ADHD arises from deficits in executive functions such as working memory, but accumulating clinical evidence suggests a dissociation between ADHD and executive dysfunctions. This study examined whether ADHD and working memory capacity are behaviorally and neurobiologically separable using functional magnetic resonance imaging (fMRI). Participants diagnosed with ADHD in childhood who subsequently remitted or persisted in their diagnosis as adults were characterized at follow-up in adulthood as either impaired or unimpaired in spatial working memory relative to controls who never had ADHD. ADHD participants with impaired spatial working memory performed worse than controls and ADHD participants with unimpaired working memory during an n-back working memory task while being scanned. Both controls and ADHD participants with unimpaired working memory exhibited significant linearly increasing activation in the inferior frontal junction, precuneus, lingual gyrus, and cerebellum as a function of working-memory load, and these activations did not differ significantly between these groups. ADHD participants with impaired working memory exhibited significant hypoactivation in the same regions, which was significantly different than both control participants and ADHD participants with unimpaired working memory. These findings support both a behavioral and neurobiological dissociation between ADHD and working memory capacity.

Dissociation of working memory impairments and attention-deficit/hyperactivity disorder in the brain

PubMed Central

Mattfeld, Aaron T.; Whitfield-Gabrieli, Susan; Biederman, Joseph; Spencer, Thomas; Brown, Ariel; Fried, Ronna; Gabrieli, John D.E.

2015-01-01

Prevailing neuropsychological models of attention-deficit/hyperactivity disorder (ADHD) propose that ADHD arises from deficits in executive functions such as working memory, but accumulating clinical evidence suggests a dissociation between ADHD and executive dysfunctions. This study examined whether ADHD and working memory capacity are behaviorally and neurobiologically separable using functional magnetic resonance imaging (fMRI). Participants diagnosed with ADHD in childhood who subsequently remitted or persisted in their diagnosis as adults were characterized at follow-up in adulthood as either impaired or unimpaired in spatial working memory relative to controls who never had ADHD. ADHD participants with impaired spatial working memory performed worse than controls and ADHD participants with unimpaired working memory during an n-back working memory task while being scanned. Both controls and ADHD participants with unimpaired working memory exhibited significant linearly increasing activation in the inferior frontal junction, precuneus, lingual gyrus, and cerebellum as a function of working-memory load, and these activations did not differ significantly between these groups. ADHD participants with impaired working memory exhibited significant hypoactivation in the same regions, which was significantly different than both control participants and ADHD participants with unimpaired working memory. These findings support both a behavioral and neurobiological dissociation between ADHD and working memory capacity. PMID:26900567

Performance-Based Empathy Mediates the Influence of Working Memory on Social Competence in Schizophrenia

PubMed Central

Smith, Matthew J.; Horan, William P.; Cobia, Derin J.; Karpouzian, Tatiana M.; Fox, Jaclyn M.; Reilly, James L.; Breiter, Hans C.

2014-01-01

Empathic deficits have been linked to poor functioning in schizophrenia, but this work is mostly limited to self-report data. This study examined whether performance-based empathy measures account for incremental variance in social competence and social attainment above and beyond self-reported empathy, neurocognition, and clinical symptoms. Given the importance of working memory in theoretical models of empathy and in the prediction of functioning in schizophrenia, we also examined whether empathy mediates the relationship between working memory and functioning. Sixty outpatients and 45 healthy controls were compared on performance-based measures of 3 key components of empathic responding, including facial affect perception, emotional empathy (affective responsiveness), and cognitive empathy (emotional perspective-taking). Participants also completed measures of self-reported empathy, neurocognition, clinical symptoms, and social competence and attainment. Patients demonstrated lower accuracy than controls across the 3 performance-based empathy measures. Among patients, these measures showed minimal relations to self-reported empathy but significantly correlated with working memory and other neurocognitive functions as well as symptom levels. Furthermore, cognitive empathy explained significant incremental variance in social competence (∆R 2 = .07, P < .05) and was found to mediate the relation between working memory and social competence. Performance-based measures of empathy were sensitive to functionally relevant disturbances in schizophrenia. Working memory deficits appear to have an important effect on these disruptions in empathy. Empathy is emerging as a promising new area for social cognitive research and for novel recovery-oriented treatment development. PMID:23770935

Obesity and unhealthy lifestyle associated with poor executive function among Malaysian adolescents.

PubMed

Tee, Joyce Ying Hui; Gan, Wan Ying; Tan, Kit-Aun; Chin, Yit Siew

2018-01-01

The understanding on the roles of obesity and lifestyle behaviors in predicting executive function of adolescents has been limited. Low executive function proficiency may have adverse effects on adolescents' school academic performance. This cross-sectional study aimed to examine the relationship between BMI-for-age and multiple lifestyle behaviors (operationalized as meal consumption, physical activity, and sleep quality) with executive function (operationalized as inhibition, working memory, and cognitive flexibility) on a sample of Malaysian adolescents aged between 12 and 16 years (N = 513). Participants were recruited from two randomly selected schools in the state of Selangor in Malaysia. Using a self-administered questionnaire, parent participants provided information concerning their sociodemographic data, whereas adolescent participants provided information regarding their meal consumptions, physical activity, and sleep quality. The modified Harvard step test was used to assess adolescents' aerobic fitness, while Stroop color-word, digit span, and trail-making tests were used to assess adolescents' inhibition, working memory, and cognitive flexibility, respectively. Three separate hierarchical regression analyses were conducted for each outcome namely, inhibition, working memory, and cognitive flexibility. After adjusted for sociodemographic factors and BMI-for-age, differential predictors of inhibition and working memory were found. Habitual sleep efficiency significantly and positively predicted inhibition. Regular dinner intakes, physical activity levels, and sleep quality significantly and positively predicted working memory. Household income emerged as a consistent predictor for all executive function domains. In conclusion, an increased trend of obesity and unhealthy lifestyles among adolescents were found to be associated with poorer executive function. Regular dinner intakes, higher physical activity levels and better sleep quality predicted better executive function despite the inverse relationship between obesity and executive function. Future studies may explore how lifestyle modifications can optimize the development of executive function in adolescents as well as relieve the burden of obesity.

The Working Memory and Dorsolateral Prefrontal-Hippocampal Functional Connectivity Changes in Long-Term Survival Breast Cancer Patients Treated with Tamoxifen

PubMed Central

Chen, Xingui; Tao, Longxiang; Li, Jingjing; Wu, Jiaonan; Zhu, Chunyan; Yu, Fengqiong; Zhang, Lei; Zhang, Jingjie; Qiu, Bensheng; Yu, Yongqiang; He, Xiaoxuan

2017-01-01

Abstract Background: Tamoxifen is the most widely used drug for treating patients with estrogen receptor-sensitive breast cancer. There is evidence that breast cancer patients treated with tamoxifen exhibit cognitive dysfunction. However, the underlying neural mechanism remains unclear. The present study aimed to investigate the neural mechanisms underlying working memory deficits in combination with functional connectivity changes in premenopausal women with breast cancer who received long-term tamoxifen treatment. Methods: A total of 31 premenopausal women with breast cancer who received tamoxifen and 32 matched healthy control participants were included. The participants completed n-back tasks and underwent resting-state functional magnetic resonance imaging, which measure working memory performance and brain functional connectivity, respectively. A seed-based functional connectivity analysis within the whole brain was conducted, for which the dorsolateral prefrontal cortex was chosen as the seed region. Results: Our results indicated that the tamoxifen group had significant deficits in working memory and general executive function performance and significantly lower functional connectivity of the right dorsolateral prefrontal cortex with the right hippocampus compared with the healthy controls. There were no significant changes in functional connectivity in the left dorsolateral prefrontal cortex within the whole brain between the tamoxifen group and healthy controls. Moreover, significant correlations were found in the tamoxifen group between the functional connectivity strength of the dorsolateral prefrontal cortex with the right hippocampus and decreased working memory performance. Conclusion: This study demonstrates that the prefrontal cortex and hippocampus may be affected by tamoxifen treatment, supporting an antagonistic role of tamoxifen in the long-term treatment of breast cancer patients. PMID:28177081

Functional Brain Organization of Working Memory in Adolescents Varies in Relation to Family Income and Academic Achievement

ERIC Educational Resources Information Center

Finn, Amy S.; Minas, Jennifer E.; Leonard, Julia A.; Mackey, Allyson P.; Salvatore, John; Goetz, Calvin; West, Martin R.; Gabrieli, Christopher F. O.; Gabrieli, John D. E.

2017-01-01

Working memory (WM) capacity reflects executive functions associated with performance on a wide range of cognitive tasks and education outcomes, including mathematics achievement, and is associated with dorsolateral prefrontal and parietal cortices. Here we asked if family income is associated with variation in the functional brain organization of…

Medial Prefrontal Lesions in Mice Impair Sustained Attention but Spare Maintenance of Information in Working Memory

ERIC Educational Resources Information Center

Kahn, Julia B.; Ward, Ryan D.; Kahn, Lora W.; Rudy, Nicole M.; Kandel, Eric R.; Balsam, Peter D.; Simpson, Eleanor H.

2012-01-01

Working memory and attention are complex cognitive functions that are disrupted in several neuropsychiatric disorders. Mouse models of such human diseases are commonly subjected to maze-based tests that can neither distinguish between these cognitive functions nor isolate specific aspects of either function. Here, we have adapted a simple visual…

Students' Competencies in Working with Functions in Secondary Mathematics Education-Empirical Examination of a Competence Structure Model

ERIC Educational Resources Information Center

Nitsch, Renate; Fredebohm, Anneke; Bruder, Regina; Kelava, Augustin; Naccarella, Dominik; Leuders, Timo; Wirtz, Markus

2015-01-01

In the subject matter of functional relationships, a student's ability to translate from one form of representation to another is seen as a central competence. In the course of the HEUREKO project (heuristic work with representations of functional relationships and the diagnosis of mathematical competencies of students), a theoretical competence…

The Assessment of Executive Functioning in People with Intellectual Disabilities: An Exploratory Analysis

ERIC Educational Resources Information Center

Bevins, Shelley; Hurse, Emily

2016-01-01

The following article details a piece of service development work undertaken as part of the Plymouth Down Syndrome Screening Programme. The work aimed to review the use of three measures assessing executive functioning skills used within the Programme as well as with people without Down syndrome. Three tasks assessing executive functioning (the…

Medial prefrontal lesions in mice impair sustained attention but spare maintenance of information in working memory.

PubMed

Kahn, Julia B; Ward, Ryan D; Kahn, Lora W; Rudy, Nicole M; Kandel, Eric R; Balsam, Peter D; Simpson, Eleanor H

2012-10-16

Working memory and attention are complex cognitive functions that are disrupted in several neuropsychiatric disorders. Mouse models of such human diseases are commonly subjected to maze-based tests that can neither distinguish between these cognitive functions nor isolate specific aspects of either function. Here, we have adapted a simple visual discrimination task, and by varying only the timing of events within the same task construct, we are able to measure independently the behavioral response to increasing attentional demand and increasing length of time that information must be maintained in working memory. We determined that mPFC lesions in mice impair attention but not working memory maintenance.

Executive functioning and reading achievement in school: a study of Brazilian children assessed by their teachers as “poor readers”

PubMed Central

Engel de Abreu, Pascale M. J.; Abreu, Neander; Nikaedo, Carolina C.; Puglisi, Marina L.; Tourinho, Carlos J.; Miranda, Mônica C.; Befi-Lopes, Debora M.; Bueno, Orlando F. A.; Martin, Romain

2014-01-01

This study examined executive functioning and reading achievement in 106 6- to 8-year-old Brazilian children from a range of social backgrounds of whom approximately half lived below the poverty line. A particular focus was to explore the executive function profile of children whose classroom reading performance was judged below standard by their teachers and who were matched to controls on chronological age, sex, school type (private or public), domicile (Salvador/BA or São Paulo/SP) and socioeconomic status. Children completed a battery of 12 executive function tasks that were conceptual tapping cognitive flexibility, working memory, inhibition and selective attention. Each executive function domain was assessed by several tasks. Principal component analysis extracted four factors that were labeled “Working Memory/Cognitive Flexibility,” “Interference Suppression,” “Selective Attention,” and “Response Inhibition.” Individual differences in executive functioning components made differential contributions to early reading achievement. The Working Memory/Cognitive Flexibility factor emerged as the best predictor of reading. Group comparisons on computed factor scores showed that struggling readers displayed limitations in Working Memory/Cognitive Flexibility, but not in other executive function components, compared to more skilled readers. These results validate the account that working memory capacity provides a crucial building block for the development of early literacy skills and extends it to a population of early readers of Portuguese from Brazil. The study suggests that deficits in working memory/cognitive flexibility might represent one contributing factor to reading difficulties in early readers. This might have important implications for how educators might intervene with children at risk of academic under achievement. PMID:24959155

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

NASA Astrophysics Data System (ADS)

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.

Cognitive Predictors of Work Among Social Security Disability Insurance Beneficiaries With Psychiatric Disorders Enrolled in IPS Supported Employment.

PubMed

McGurk, Susan R; Drake, Robert E; Xie, Haiyi; Riley, Jarnee; Milfort, Roline; Hale, Thomas W; Frey, William

2018-01-13

Impaired cognitive functioning is a significant predictor of work dysfunction in schizophrenia. Less is known, however about relationships of cognition and work in people with less severe disorders with relatively normal cognitive functioning. This secondary analysis evaluated cognitive predictors of work in Social Security Disability Insurance (SSDI) beneficiaries with a recent work history who were randomized to receive mental health services, supported employment, and freedom from work disincentives over a 2-year study period in the Mental Health Treatment Study. Of the 1045 participants randomized to the treatment package, 945 (90.4%) received a cognitive assessment at study entry. Competitive work activity was evaluated using a computer-assisted timeline follow-back calendar at baseline and quarterly for 24 months. Mood disorders were the most common psychiatric diagnoses (64.9%), followed by schizophrenia or schizoaffective disorder (35.1%). Tobit regression analyses predicting the average number of hours worked per week, controlling for demographic characteristics, diagnosis, and work history indicated that the cognitive composite score (P < .01) and verbal learning subscale scores (P < .001) were associated with fewer hours of weekly work over the study period. Cognitive functioning predicted work over 2 years in SSDI beneficiaries with mood or schizophrenia-spectrum disorders who were receiving supported employment and mental health interventions, despite a relative absence of cognitive impairment in the study participants. The findings suggest cognitive functioning contributes to competitive work outcomes in persons with psychiatric disorders who have relatively unimpaired cognitive abilities, even under optimal conditions of treatment and vocational support. © The Author(s) 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.

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

PubMed

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 (p<0.001) with CON outperforming both SCZ groups in all neurocognitive domains. Post-hoc tests revealed that HF-SCZ had higher verbal working memory compared to LF-SCZ (p≤0.05, Cohen's d=0.78) but the two groups did not differ in remaining domains. The cluster 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.

Working set selection using functional gain for LS-SVM.

PubMed

Bo, Liefeng; Jiao, Licheng; Wang, Ling

2007-09-01

The efficiency of sequential minimal optimization (SMO) depends strongly on the working set selection. This letter shows how the improvement of SMO in each iteration, named the functional gain (FG), is used to select the working set for least squares support vector machine (LS-SVM). We prove the convergence of the proposed method and give some theoretical support for its performance. Empirical comparisons demonstrate that our method is superior to the maximum violating pair (MVP) working set selection.

An audit of the laboratory service provided to the Health Service Executive Orthodontic Department, St James Hospital, Dublin.

PubMed

Al-Awadhi, E A; Wolstencroft, S J; Blake, M

2006-01-01

To evaluate the service purchased from contracted orthodontic laboratories used by HSE (SWA) regional orthodontic unit, St. James's Hospital, Dublin and identify deficiencies in the current service. A data collection questionnaire was designed and distributed to the departmental orthodontists for a period of three months (October-December 2004). Gold standards, drawn up based on the authors' ideal requirements and published guidelines, were supplied to grade the work returned. During the study period 363 items of laboratory work were requested. 20% of the laboratory work arrived late and most of the delayed work was delayed for more than 24 hours. Most laboratory delays occurred with functional appliances, retainers and study models. Prior to fit, 20% of the appliances required adjustments for more than 30 seconds. 65% of laboratory work returned to the department met all of the gold standards. 10% of appliances were considered unsatisfactory. Functional appliances were most often ill fitting accounting for almost half of the unsatisfactory laboratory work. The majority of the laboratory work returned to the department met our gold standards and arrived on time. Forty six percent of the appliances required adjustments. Functional appliances required the most adjustments; one in five of all functional appliances ordered were considered unsatisfactory.

No lower cognitive functioning in older adults with attention-deficit/hyperactivity disorder.

PubMed

Semeijn, E J; Korten, N C M; Comijs, H C; Michielsen, M; Deeg, D J H; Beekman, A T F; Kooij, J J S

2015-09-01

Research illustrates cognitive deficits in children and younger adults with attention-deficit/hyperactivity disorder (ADHD). Few studies have focused on the cognitive functioning in older adults. This study investigates the association between ADHD and cognitive functioning in older adults. Data were collected in a cross-sectional side study of the Longitudinal Aging Study Amsterdam (LASA). A diagnostic interview to diagnose ADHD was administered among a subsample (N = 231, age 60-94). ADHD symptoms and diagnosis were assessed with the Diagnostic Interview for ADHD in Adults (DIVA) 2.0. Cognitive functioning was assessed with tests in the domains of executive functioning, information processing speed, memory, and attention/working memory. Regression analyses indicate that ADHD diagnosis and ADHD severity were only negatively associated with cognitive functioning in the attention/working memory domain. When adjusting for depression, these associations were no longer significant. The study shows that ADHD in older adults is associated with lower cognitive functioning in the attention/working memory domain. However, this was partly explained by depressive symptoms.

Improving Assessment of Work Related Mental Health Function Using the Work Disability Functional Assessment Battery (WD-FAB).

PubMed

Marfeo, Elizabeth E; Ni, Pengsheng; McDonough, Christine; Peterik, Kara; Marino, Molly; Meterko, Mark; Rasch, Elizabeth K; Chan, Leighton; Brandt, Diane; Jette, Alan M

2018-03-01

Purpose To improve the mental health component of the Work Disability Functional Assessment Battery (WD-FAB), developed for the US Social Security Administration's (SSA) disability determination process. Specifically our goal was to expand the WD-FAB scales of mood & emotions, resilience, social interactions, and behavioral control to improve the depth and breadth of the current scales and expand the content coverage to include aspects of cognition & communication function. Methods Data were collected from a random, stratified sample of 1695 claimants applying for the SSA work disability benefits, and a general population sample of 2025 working age adults. 169 new items were developed to replenish the WD-FAB scales and analyzed using factor analysis and item response theory (IRT) analysis to construct unidimensional scales. We conducted computer adaptive test (CAT) simulations to examine the psychometric properties of the WD-FAB. Results Analyses supported the inclusion of four mental health subdomains: Cognition & Communication (68 items), Self-Regulation (34 items), Resilience & Sociability (29 items) and Mood & Emotions (34 items). All scales yielded acceptable psychometric properties. Conclusions IRT methods were effective in expanding the WD-FAB to assess mental health function. The WD-FAB has the potential to enhance work disability assessment both within the context of the SSA disability programs as well as other clinical and vocational rehabilitation settings.

Increase of intrinsic emittance induced by multiphoton photoemission from copper cathodes illuminated by femtosecond laser pulses

NASA Astrophysics Data System (ADS)

An, Chenjie; Zhu, Rui; Xu, Jun; Liu, Yaqi; Hu, Xiaopeng; Zhang, Jiasen; Yu, Dapeng

2018-05-01

Electron sources driven by femtosecond laser have important applications in many aspects, and the research about the intrinsic emittance is becoming more and more crucial. The intrinsic emittance of polycrystalline copper cathode, which was illuminated by femtosecond pulses (FWHM of the pulse duration was about 100 fs) with photon energies above and below the work function, was measured with an extremely low bunch charge (single-electron pulses) based on free expansion method. A minimum emittance was obtained at the photon energy very close to the effective work function of the cathode. When the photon energy decreased below the effective work function, emittance increased rather than decreased or flattened out to a constant. By investigating the dependence of photocurrent density on the incident laser intensity, we found the emission excited by pulsed photons with sub-work-function energies contained two-photon photoemission. In addition, the portion of two-photon photoemission current increased with the reduction of photon energy. We attributed the increase of emittance to the effect of two-photon photoemission. This work shows that conventional method of reducing the photon energy of excited light source to approach the room temperature limit of the intrinsic emittance may be infeasible for femtosecond laser. There would be an optimized photon energy value near the work function to obtain the lowest emittance for pulsed laser pumped photocathode.

Psychosocial Work Characteristics Predict Cardiovascular Disease Risk Factors and Health Functioning in Rural Women: The Wisconsin Rural Women's Health Study

ERIC Educational Resources Information Center

Chikani, Vatsal; Reding, Douglas; Gunderson, Paul; McCarty, Catherine A.

2005-01-01

Background: The aim of the present study is to investigate the association between psychosocial work characteristics and health functioning and cardiovascular disease risk factors among rural women of central Wisconsin and compare psychosocial work characteristics between farm and nonfarm women. Methods: Stratified sampling was used to select a…

The Contributions of Working Memory and Executive Functioning to Problem Representation and Solution Generation in Algebraic Word Problems

ERIC Educational Resources Information Center

Lee, Kerry; Ng, Ee Lynn; Ng, Swee Fong

2009-01-01

Solving algebraic word problems involves multiple cognitive phases. The authors used a multitask approach to examine the extent to which working memory and executive functioning are associated with generating problem models and producing solutions. They tested 255 11-year-olds on working memory (Counting Recall, Letter Memory, and Keep Track),…

Manage Work Better to Better Manage Human Resources: A Comparative Study of Two Approaches to Job Analysis.

ERIC Educational Resources Information Center

Clifford, James P.

1996-01-01

The Position Classification Questionnaire (PCQ) and task inventory method (TI) were used to study the same work functions. PCQ divided functions into 16 classes for wage/salary determination. TI divided them into 28 classifications for training purposes. The two approaches were considerably different in their approach to how work should be…

The reduction of occupational stress among elderly lawyers: the creation of a functional niche.

PubMed

Meltzer, M W

1981-01-01

The question of how older lawyers function in the context of what is generally a high stress occupation is examined from data drawn from a random stratified sample of 130 members of the legal profession. It is shown that elderly lawyers are able to reduce work stress (largely deriving from volume, responsibility, clients, and trials) by control over the quantity and focus of their work, as well as through client selection. Elderly lawyers are able to create a relatively stress free work role, which is in fact a functional niche for them within the profession. The result is high job satisfaction and low rates of retirement among elderly practitioners. Two factors: work role compensation and work role autonomy, are isolated from the legal data and proposed as important variables in a general theory of retirement behavior.

Respiratory dysfunction in swine production facility workers: dose-response relationships of environmental exposures and pulmonary function.

PubMed

Donham, K J; Reynolds, S J; Whitten, P; Merchant, J A; Burmeister, L; Popendorf, W J

1995-03-01

Human respiratory health hazards for people working in livestock confinement buildings have been recognized since 1974. However, before comprehensive control programs can be implemented, more knowledge is needed of specific hazardous substances present in the air of these buildings, and at what concentrations they are harmful. Therefore, a medical epidemiological and exposure-response study was conducted on 207 swine producers using intensive housing systems (108 farms). Dose-response relationships between pulmonary function and exposures are reported here. Positive correlations were seen between change in pulmonary function over a work period and exposure to total dust, respirable dust, ammonia, respirable endotoxin, and the interactions of age-of-producer and dust exposure and years-of-working-in-the-facility and dust exposure. Relationships between baseline pulmonary function and exposures were not strong and therefore, not pursued in this study. The correlations between exposure and response were stronger after 6 years of exposure. Multiple regression models were used to identify total dust and ammonia as the two primary environmental predictors of pulmonary function decrements over a work period. The regression models were then used to determine exposure concentrations related to pulmonary function decrements suggestive of a health hazard. Total dust concentrations > or = 2.8 mg/m3 were predictive of a work period decrement of > or = 10% in FEV1. Ammonia concentrations of > or = 7.5 ppm were predictive of a > or = 3% work period decrement in FEV1. These predictive concentrations were similar to a previous dose-response study, which suggested 2.5 mg/m3 of total dust and 7 ppm of NH3 were associated with significant work period decrements. Therefore, dust > or = 2.8 mg/m3 and ammonia > or = 7.5 ppm should be considered reasonable evidence for guidelines regarding hazardous exposure concentrations in this work environment.

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

PubMed Central

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 and sparse connections between modules may reflect effective signaling across brain regions, perhaps through the modulation of signal or the suppression of the propagation of noise. PMID:22276205

Exploring novice nurses' needs regarding their work-related health: a qualitative study.

PubMed

Ketelaar, Sarah M; Nieuwenhuijsen, Karen; Frings-Dresen, Monique H W; Sluiter, Judith K

2015-10-01

To investigate Dutch novice nurses' experiences and needs regarding occupational health support to prevent work-related health problems and to keep them well-functioning. A qualitative interview study was conducted with six nursing students and eight newly qualified nurses. The interviews covered three topics: experiences with the link between work and health, received occupational health support, and occupational health support needs. Data were analysed using a grounded theory approach. Participants reported experiences with work-related health problems early in their career and described experiences with how health problems lead to suboptimal work functioning. Occupational health support needs included knowledge and psychosocial support during nursing education, e.g. through paying attention to dealing with shift work, or career counselling. Also, they reported a need for knowledge and psychosocial support at the start of their clinical placement or new job in the hospital, e.g. information from occupational health services or having a mentor. Furthermore, they reported that occupational health support requires a more general place at work through offering knowledge, e.g. tailored advice on proper lifting position; psychosocial support, e.g. positive team atmosphere; and physical support, e.g. suitable preventive measures. Occupational health support for novice nurses is important, since they already experience work-related health problems and suboptimal work functioning due to health problems early in their career and while still in training to be a nurse. Novice nurses should be given more knowledge and support to help them stay healthy and well-functioning in their work. This is a joint responsibility of nurse educators, the employer and occupational health services.

Benefits of regular aerobic exercise for executive functioning in healthy populations.

PubMed

Guiney, Hayley; Machado, Liana

2013-02-01

Research suggests that regular aerobic exercise has the potential to improve executive functioning, even in healthy populations. The purpose of this review is to elucidate which components of executive functioning benefit from such exercise in healthy populations. In light of the developmental time course of executive functions, we consider separately children, young adults, and older adults. Data to date from studies of aging provide strong evidence of exercise-linked benefits related to task switching, selective attention, inhibition of prepotent responses, and working memory capacity; furthermore, cross-sectional fitness data suggest that working memory updating could potentially benefit as well. In young adults, working memory updating is the main executive function shown to benefit from regular exercise, but cross-sectional data further suggest that task-switching and post error performance may also benefit. In children, working memory capacity has been shown to benefit, and cross-sectional data suggest potential benefits for selective attention and inhibitory control. Although more research investigating exercise-related benefits for specific components of executive functioning is clearly needed in young adults and children, when considered across the age groups, ample evidence indicates that regular engagement in aerobic exercise can provide a simple means for healthy people to optimize a range of executive functions.

[Influence of work intensity on development of arterial hypertension in metal-mining workers].

PubMed

Ustinova, O Iu; Alekseev, V B; Rumiantseva, A N; Orehova, Ia V

2013-01-01

The article covers data on influence of working shifts duration and shift work intensity on cardiovascular system functioning in operators of mining excavators. Findings are that 8 hours shift with regular shift schedule (40 working hours per week) gives significant load on cardiovascular system of workers engaged into underground activities. 50% of mining excavator operators following this working schedule develop transitory arterial hypertension within 10 years. Longer work shift over 8 hours and more intensive shifting schedule over 40 hours per week causes stable arterial hypertension within 3 months in 60% of workers, in 10% of cases associated with lower functioning of sinus node.

High visual working memory capacity in trait social anxiety.

PubMed

Moriya, Jun; Sugiura, Yoshinori

2012-01-01

Working memory capacity is one of the most important cognitive functions influencing individual traits, such as attentional control, fluid intelligence, and also psychopathological traits. Previous research suggests that anxiety is associated with impaired cognitive function, and studies have shown low verbal working memory capacity in individuals with high trait anxiety. However, the relationship between trait anxiety and visual working memory capacity is still unclear. Considering that people allocate visual attention more widely to detect danger under threat, visual working memory capacity might be higher in anxious people. In the present study, we show that visual working memory capacity increases as trait social anxiety increases by using a change detection task. When the demand to inhibit distractors increased, however, high visual working memory capacity diminished in individuals with social anxiety, and instead, impaired filtering of distractors was predicted by trait social anxiety. State anxiety was not correlated with visual working memory capacity. These results indicate that socially anxious people could potentially hold a large amount of information in working memory. However, because of an impaired cognitive function, they could not inhibit goal-irrelevant distractors and their performance decreased under highly demanding conditions.

78. Augmenting NMDA Receptor Signaling Enhances Working Memory and Alters Gamma Oscillations in Patients With Schizophrenia

PubMed Central

Forsyth, Jennifer; Bachman, Peter; Asarnow, Robert

2017-01-01

Abstract Background: Gamma band oscillations (30–80 Hz) are associated with numerous sensory and higher cognitive functions and are abnormal in patients with schizophrenia. Glutamate signaling at the N-methyl-D-aspartate receptor (NMDAR) is theorized to play a key role in the pathophysiology of schizophrenia and NMDAR antagonists disrupt working memory and gamma oscillations in healthy individuals. It has therefore been suggested that NMDAR dysfunction may contribute to abnormalities in gamma oscillations and working memory in schizophrenia. In the current study, we examined the effects of acutely augmenting NMDAR signaling using the NMDAR agonist, d-cycloserine (DCS), on working memory and gamma power in patients with schizophrenia. Methods: In a double-blind design, patients with schizophrenia were randomized to receive a single dose of 100 mg DCS (SZ-DCS; n = 24) or Placebo (SZ-PLC; n = 21). Patients completed a spatial n-back task involving a 0-back control condition and 1-back and 2-back working memory loads while undergoing EEG recording. Gamma power (30–80 Hz) during the 0-back condition assessed gamma power associated with basic perceptual, motor, and attentive processes. Change in gamma power for correct working memory trials relative to the 0-back condition assessed gamma power associated with working memory function. Results: Among patients who performed above chance (SZ-DCS = 17, SZ-PLC = 16), patients who received DCS showed superior working memory performance compared to patients who received Placebo. Gamma power during the 0-back control condition was similar between SZ-DCS and SZ-PLC who performed above chance. However, gamma power associated with working memory function was significantly suppressed in SZ-DCS compared to SZ-PLC, particularly over frontal right channels. In addition, whereas higher working memory gamma power over frontal right channels was associated with better working memory performance in SZ-PLC, this relationship was not evident in SZ-DCS. Conclusion: Results suggest that augmenting NMDAR signaling enhanced working memory performance and suppressed gamma activity associated with working memory function in patients with schizophrenia. Given prior reports that schizophrenia patients may utilize excessive gamma power for successful working memory performance, these findings suggest that augmenting NMDAR signaling may improve the efficiency of neural encoding for successful working memory function in schizophrenia.

Domains of cognitive function in early old age: which ones are predicted by pre-retirement psychosocial work characteristics?

PubMed

Sabbath, Erika L; Andel, Ross; Zins, Marie; Goldberg, Marcel; Berr, Claudine

2016-10-01

Psychosocial work characteristics may predict cognitive functioning after retirement. However, little research has explored specific cognitive domains associated with psychosocial work environments. Our study tested whether exposure to job demands, job control and their combination during working life predicted post-retirement performance on eight cognitive tests. We used data from French GAZEL cohort members who had undergone post-retirement cognitive testing (n=2149). Psychosocial job characteristics were measured on average for 4 years before retirement using Karasek's Job Content Questionnaire (job demands, job control and demand-control combinations). We tested associations between these exposures and post-retirement performance on tests for executive function, visual-motor speed, psychomotor speed, verbal memory, and verbal fluency using ordinary least squares regression. Low job control during working life was negatively associated with executive function, psychomotor speed, phonemic fluency and semantic fluency after retirement (p's<0.05), even after adjustment for demographics, socioeconomic status, health and social behaviours and vascular risk factors. Both passive (low-demand, low-control) and high-strain (high-demand, low-control) jobs were associated with lower scores on phonemic and semantic fluency when compared to low-strain (low-demand, high-control) jobs. Low job control, in combination with both high and low-job demands, is associated with post-retirement deficits in some, but not all, cognitive domains. In addition to work stress, associations between passive work and subsequent cognitive function may implicate lack of cognitive engagement at work as a risk factor for future cognitive difficulties. 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/

Are intrinsic motivational factors of work associated with functional incapacity similarly regardless of the country?

PubMed

Väänänen, A; Pahkin, K; Huuhtanen, P; Kivimäki, M; Vahtera, J; Theorell, T; Kalimo, R

2005-10-01

Many psychosocial models of wellbeing at work emphasise the role of intrinsic motivational factors such as job autonomy, job complexity, and innovativeness. However, little is known about whether the employees of multinational enterprises differ from country to country with regard to intrinsic motivational factors, and whether these factors are associated with wellbeing similarly in the different countries. The purpose of this study was to examine the level of intrinsic motivational factors and their impact on functional incapacity in different countries in a multinational corporation. In 2000, data were collected from a globally operating corporation with a questionnaire survey. The participants were 13 795 employees (response rate 59%; 56% under age 45; 80% men; 61% blue collar employees), who worked in similar industrial occupations in five countries (Canada, China, Finland, France, and Sweden). The Chinese employees reported higher autonomy and lower complexity at work than the employees from the other countries. After adjustment for age, sex, socioeconomic status, and physical work environment, job autonomy, and job complexity at work were associated with functional incapacity in most countries, whereas in China the impact was significantly stronger. In Finland and in China employees with low innovativeness at work were more prone to functional incapacity than corresponding employees in other countries. The level of intrinsic motivational factors varied between the Chinese employees and those in other countries. In line with theoretical notions, the relation between intrinsic motivational factors of work and functional incapacity followed a similar pattern in the different countries. However, these country specific results show that a culture specific approach to employee wellbeing should also be applied.

Sintered wire cathode

DOEpatents

Falce, Louis R [San Jose, CA; Ives, R Lawrence [Saratoga, CA

2009-06-09

A porous cathode structure is fabricated from a plurality of wires which are placed in proximity to each other in elevated temperature and pressure for a sintering time. The sintering process produces the porous cathode structure which may be divided into a plurality of individual porous cathodes, one of which may be placed into a dispenser cathode support which includes a cavity for containing a work function reduction material such as BaO, CaO, and Al.sub.2O.sub.3. The work function reduction material migrates through the pores of the porous cathode from a work replenishment surface adjacent to the cavity of the dispenser cathode support to an emitting cathode surface, thereby providing a dispenser cathode which has a uniform work function and therefore a uniform electron emission.

The Relationship between Symptom Relief and Psychosocial Functional Improvement during Acute Electroconvulsive Therapy for Patients with Major Depressive Disorder.

PubMed

Lin, Ching-Hua; Yang, Wei-Cheng

2017-07-01

We aimed to compare the degree of symptom relief to psychosocial functional (abbreviated as "functional") improvement and explore the relationships between symptom relief and functional improvement during acute electroconvulsive therapy for patients with major depressive disorder. Major depressive disorder inpatients (n=130) requiring electroconvulsive therapy were recruited. Electroconvulsive therapy was generally performed for a maximum of 12 treatments. Symptom severity, using the 17-item Hamilton Depression Rating Scale, and psychosocial functioning (abbreviated as "functioning"), using the Modified Work and Social Adjustment Scale, were assessed before electroconvulsive therapy, after every 3 electroconvulsive therapy treatments, and after the final electroconvulsive therapy. Both 17-item Hamilton Depression Rating Scale and Modified Work and Social Adjustment Scale scores were converted to T-score units to compare the degrees of changes between depressive symptoms and functioning after electroconvulsive therapy. Structural equation modeling was used to test the relationships between 17-item Hamilton Depression Rating Scale and Modified Work and Social Adjustment Scale during acute electroconvulsive therapy. One hundred sixteen patients who completed at least the first 3 electroconvulsive therapy treatments entered the analysis. Reduction of 17-item Hamilton Depression Rating Scale T-scores was significantly greater than that of Modified Work and Social Adjustment Scale T-scores at assessments 2, 3, 4, and 5. The model analyzed by structural equation modeling satisfied all indices of goodness-of-fit (chi-square = 32.882, P =.107, TLI = 0.92, CFI = 0.984, RMSEA = 0.057). The 17-item Hamilton Depression Rating Scale change did not predict subsequent Modified Work and Social Adjustment Scale change. Functioning improved less than depressive symptoms during acute electroconvulsive therapy. Symptom reduction did not predict subsequent functional improvement. Depressive symptoms and functional impairment are distinct domains and should be assessed independently to accurately reflect the effectiveness of electroconvulsive therapy. © The Author 2017. Published by Oxford University Press on behalf of CINP.

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

PubMed

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.

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

PubMed Central

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

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. Trial Registration UMIN Clinical Trial Registry 000005618. PMID:23405164

The interplay between emotional exhaustion, common mental disorders, functioning and health care use in the working population.

PubMed

Tuithof, Marlous; Ten Have, Margreet; Beekman, Aartjan; van Dorsselaer, Saskia; Kleinjan, Marloes; Schaufeli, Wilmar; de Graaf, Ron

2017-09-01

Previous research established that emotional exhaustion - the often assumed core dimension of burnout - diminishes job-related functioning, but knowledge of its association with functioning and health care utilization is largely lacking. Moreover, as exhaustion frequently co-occurs with mood and anxiety disorders (i.e. common mental disorders (CMD)), the question should be addressed whether these associations hold after adjustment for CMD, and whether CMD intensifies the burden of exhaustion. Cross-sectional data was used from 2902 workers included in the third wave of the Netherlands Mental Health Survey and Incidence Study-2, a nationally representative face-to-face survey. Exhaustion was assessed with the exhaustion scale of the Maslach Burnout Inventory; work loss (including presenteeism and absenteeism) with the WHO Disability Assessment Schedule; and general functioning with the 36-item Short Form. Health care use is defined as ≥1 general or mental health care contact for mental health problems. Confounders included sociodemographics, job characteristics, CMD, and physical health. The Composite International Diagnostic Interview assessed CMD. Mild and severe exhaustion occurred in 14.9% and 2.3% of the workers, respectively, and was significantly associated with work loss, impaired emotional, physical and social functioning, and health care use, even after adjustment for confounders. Co-occurrence of CMD strengthened the association between exhaustion and work loss as well as impaired emotional and social functioning. Exhaustion is uniquely associated with work loss, impaired functioning and health care use. Moreover, co-occurring CMD intensified impairments in functioning. This stresses the need for clinical attention to the exhaustion dimension of burnout. Copyright © 2017 Elsevier Inc. All rights reserved.

What is the impact of shift work on the psychological functioning and resilience of nurses? An integrative review.

PubMed

Tahghighi, Mozhdeh; Rees, Clare S; Brown, Janie A; Breen, Lauren J; Hegney, Desley

2017-09-01

To synthesize existing research to determine if nurses who work shifts have poorer psychological functioning and resilience than nurses who do not work shifts. Research exploring the impact of shift work on the psychological functioning and resilience of nurses is limited compared with research investigating the impact of shifts on physical outcomes. Integrative literature review. Relevant databases were searched from January 1995-August 2016 using the combination of keywords: nurse, shift work; rotating roster; night shift; resilient; hardiness; coping; well-being; burnout; mental health; occupational stress; compassion fatigue; compassion satisfaction; stress; anxiety; depression. Two authors independently performed the integrative review processes proposed by Whittemore and Knafl and a quality assessment using the mixed-methods appraisal tool by Pluye et al. A total of 37 articles were included in the review (32 quantitative, 4 qualitative and 1 mixed-methods). Approximately half of the studies directly compared nurse shift workers with non-shift workers. Findings were grouped according to the following main outcomes: (1) general psychological well-being/quality of life; (2) Job satisfaction/burnout; (3) Depression, anxiety and stress; and (4) Resilience/coping. We did not find definitive evidence that shift work is associated with poorer psychological functioning in nurses. Overall, the findings suggest that the impact of shift work on nurse psychological functioning is dependent on several contextual and individual factors. More studies are required which directly compare the psychological outcomes and resilience of nurse shift workers with non-shift workers. © 2017 John Wiley & Sons Ltd.

Association between mental demands at work and cognitive functioning in the general population - results of the health study of the Leipzig research center for civilization diseases (LIFE).

PubMed

Then, Francisca S; Luck, Tobias; Luppa, Melanie; Arélin, Katrin; Schroeter, Matthias L; Engel, Christoph; Löffler, Markus; Thiery, Joachim; Villringer, Arno; Riedel-Heller, Steffi G

2014-01-01

The level of mental demands in the workplace is rising. The present study investigated whether and how mental demands at work are associated with cognitive functioning in the general population. The analysis is based on data of the Health Study of the Leipzig Research Centre for Civilization Disease (LIFE). 2,725 participants aged 40-80 years underwent cognitive testing (Trail-Making Test, Verbal Fluency Test) and provided information on their occupational situation. Participants over the age of 65 years additionally completed the Mini-Mental State Examination. Mental demands at work were rated by a standardized classification system (O*NET). The association between mental demands and cognitive functioning was analyzed using Generalized Linear Modeling (GENLIN) adjusted for age, gender, self-regulation, working hour status, education, and health-related factors. Univariate as well as multivariate analyses demonstrated significant and highly consistent effects of higher mental demands on better performance in cognitive testing. The results also indicated that the effects are independent of education and intelligence. Moreover, analyses of retired individuals implied a significant association between high mental demands at work of the job they once held and a better cognitive functioning in old age. In sum, our findings suggest a significant association between high mental demands at work and better cognitive functioning. In this sense, higher levels of mental demands - as brought about by technological changes in the working environment - may also have beneficial effects for the society as they could increase cognitive capacity levels and might even delay cognitive decline in old age.

Physical function improvements and relief from fatigue and pain are associated with increased productivity at work and at home in rheumatoid arthritis patients treated with certolizumab pegol

PubMed Central

Taylor, Peter; Strand, Vibeke; Purcaru, Oana; Coteur, Geoffroy; Mease, Philip

2010-01-01

Objectives. To evaluate the association between improvements in physical function, fatigue and pain and improvements in productivity at work and at home in patients treated with certolizumab pegol (CZP) in combination with MTX. Methods. Physical function, fatigue and pain were assessed in two CZP clinical trials (Rheumatoid Arthritis PreventIon of structural Damage 1 and 2) using the HAQ-Disability Index (HAQ-DI), Fatigue Assessment Scale (FAS) and Patient Assessment of Pain, with minimal clinically important differences (MCIDs) defined as ≥0.22, ≥1 and ≥10 points, respectively. Work and home productivity were evaluated using the RA-specific Work Productivity Survey (WPS-RA). The odds of achieving an HAQ-DI, FAS or pain ‘response’ at Week 12, defined as improvements ≥MCID, were compared between CZP and control groups. Improvements in productivity at Week 12 were compared between CZP-treated HAQ-DI, FAS or pain responders and non-responders. Results. The odds of achieving improvements ≥MCID were five times higher for pain, and two to three times higher for physical function and fatigue, in patients receiving CZP vs control. Per month, responders reported significantly greater improvements in productivity at work and reduced interference of RA with their work productivity than non-responders. Responders also reported significantly greater improvements in productivity at home and participation in family, social and leisure activities. Conclusions. This study demonstrated a clear association between patient-reported improvements in physical function, fatigue and pain, and improvements in productivity both at work and home. PMID:20547658

Executive functions predict conceptual learning of science.

PubMed

Rhodes, Sinéad M; Booth, Josephine N; Palmer, Lorna Elise; Blythe, Richard A; Delibegovic, Mirela; Wheate, Nial J

2016-06-01

We examined the relationship between executive functions and both factual and conceptual learning of science, specifically chemistry, in early adolescence. Sixty-three pupils in their second year of secondary school (aged 12-13 years) participated. Pupils completed tasks of working memory (Spatial Working Memory), inhibition (Stop-Signal), attention set-shifting (ID/ED), and planning (Stockings of Cambridge), from the CANTAB. They also participated in a chemistry teaching session, practical, and assessment on the topic of acids and alkalis designed specifically for this study. Executive function data were related to (1) the chemistry assessment which included aspects of factual and conceptual learning and (2) a recent school science exam. Correlational analyses between executive functions and both the chemistry assessment and science grades revealed that science achievements were significantly correlated with working memory. Linear regression analysis revealed that visuospatial working memory ability was predictive of chemistry performance. Interestingly, this relationship was observed solely in relation to the conceptual learning condition of the assessment highlighting the role of executive functions in understanding and applying knowledge about what is learned within science teaching. © 2016 The British Psychological Society.

Ab initio study of the effects of thin CsI coatings on the work function of graphite cathodes

NASA Astrophysics Data System (ADS)

Vlahos, Vasilios; Booske, John H.; Morgan, Dane

2007-10-01

Cesium-iodide (CsI)-coated graphite cathodes are promising electron sources for high power microwave generators, but the mechanism driving the improved emission is not well understood. Therefore, an ab initio modeling investigation on the effects of thin CsI coatings on graphite has been carried out. It is demonstrated that the CsI coatings reduce the work function of the system significantly through a mechanism of induced dipoles. The results suggest that work function modification is a major contribution to the improved emission seen when CsI coatings are applied to C.

Stress at the place of work and cognitive functions among women performing intellectual work during peri- and post-menopausal period.

PubMed

Gujski, Mariusz; Pinkas, Jarosław; Juńczyk, Tomasz; Pawełczak-Barszczowska, Adrianna; Raczkiewicz, Dorota; Owoc, Alfred; Bojar, Iwona

2017-10-06

The analysis of the relationship between stress at work and results of cognitive functions amongst women, at peri- and post-menopausal age, performing intellectual work. The study group included women, aged 45-66 years old, employed as intellectual workers. Research instruments were: the Montreal Cognitive Assessment; computer tests of the CNS Vital Signs; the Subjective Work Characteristics Questionnaire, and a questionnaire designed by the author. The results were statistically analyzed. Nearly a half of respondents experienced high stress at the place of work; 1/3 - on the average level, on a low level - every fifth. The largest number of respondents experienced stress caused by social contacts. Among a half of the women, stress was caused by the lack of awards at work, followed by the lack of support. Slightly fewer of them experienced stress caused by the feeling of psychological load related to the complexity of work or the feeling of uncertainty caused by the organization of work. Every third woman experienced stress due to the sense of responsibility or the lack of control. The smallest number experienced stress caused by physical arduousness, the sense of threat and unpleasant working conditions. The examined women obtained the best results with respect to simple attention, the worst results - with respect to the reaction time. The results concerning the remaining 9 cognitive functions were ranked in the middle of the aforementioned results. The intensity of stress at work and factors which caused this stress, negatively correlated with simple attention of women in the early peri-menopausal period, while positively correlating with the psychomotor and processing speed of women in the late peri-menopausal period. Among the post-menopausal women, negative correlations were observed between the majority of cognitive functions and the intensity of stress at work, and the majority of factors which caused this stress. Cognitive functions of the examined women remained within the range of average evaluations, and were correlated with stress-inducing factors at the place of work. Int J Occup Med Environ Health 2017;30(6):943-961. This work is available in Open Access model and licensed under a CC BY-NC 3.0 PL license.

Functions & Requirements for Debris Removal System Project A-2

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

PRECECHTEL, D.R.

1999-12-29

This revision of the Functions and Requirements Document updates the approved Functions and Requirements for Debris Removal Subproject WHC-SD-SNF-FRD-009, Rev. 0. It has been revised in its entirety to reflect the current scope of work for Debris Removal as canisters and lids under the K Basin Projects work breakdown structure (WBS). In this revision the canisters and lids will be consider debris and a new set of Functions and Requirements have been developed to remove the canisters and lids from the basin.

The Influence of Pre-stimulus EEG Activity on Reaction Time During a Verbal Sternberg Task is Related to Musical Expertise.

PubMed

Klein, Carina; Diaz Hernandez, Laura; Koenig, Thomas; Kottlow, Mara; Elmer, Stefan; Jäncke, Lutz

2016-01-01

Previous work highlighted the possibility that musical training has an influence on cognitive functioning. The suggested reason for this influence is the strong recruitment of attention, planning, and working memory functions during playing a musical instrument. The purpose of the present work was twofold, namely to evaluate the general relationship between pre-stimulus electrophysiological activity and cognition, and more specifically the influence of musical expertise on working memory functions. With this purpose in mind, we used covariance mapping analyses to evaluate whether pre-stimulus electroencephalographic activity is predictive for reaction time during a visual working memory task (Sternberg paradigm) in musicians and non-musicians. In line with our hypothesis, we replicated previous findings pointing to a general predictive value of pre-stimulus activity for working memory performance. Most importantly, we also provide first evidence for an influence of musical expertise on working memory performance that could distinctively be predicted by pre-stimulus spectral power. Our results open novel perspectives for better comprehending the vast influences of musical expertise on cognition.

Working Memory Arrest in Children with High-Functioning Autism Compared to Children with Attention-Deficit/Hyperactivity Disorder: Results from a 2-Year Longitudinal Study

ERIC Educational Resources Information Center

Andersen, Per N.; Skogli, Erik W.; Hovik, Kjell T.; Geurts, Hilde; Egeland, Jens; Øie, Merete

2015-01-01

The aim of this study was to analyse the development of verbal working memory in children with high-functioning autism compared to children with attention-deficit/hyperactivity disorder and typically developing children. A total of 34 children with high-functioning autism, 72 children with attention-deficit/hyperactivity disorder and 45 typically…

Lifetime achievement patterns, retirement and life satisfaction of gifted aged women.

PubMed

Holahan, C K

1981-11-01

The relationship of lifetime achievement patterns and retirement to life satisfaction for gifted aging women was investigated. Participants were 352 women in Terman's study of the gifted who were surveyed in 1977 at a mean age of 66. Lifetime achievement pattern was defined by either homemaker, job, or career work history. Dependent variables included health, happiness, life satisfaction, work attitudes, ambitions and aspirations, and participation in leisure activities. Results showed variations on life satisfaction measures as a function of lifetime career, with job holders generally less satisfied. There was a significant interaction between marital status and work pattern on overall life satisfaction suggesting an additive negative effect on the older woman of loss of spouse and a work history of working for income alone. Activity involvement varied as a function of retirement status and was differentially related to life satisfaction as a function of retirement status and career pattern.

Working Memory and Cognitive Flexibility Mediates Visuoconstructional Abilities in Older Adults with Heterogeneous Cognitive Ability.

PubMed

Ávila, Rafaela T; de Paula, Jonas J; Bicalho, Maria A; Moraes, Edgar N; Nicolato, Rodrigo; Malloy-Diniz, Leandro F; Diniz, Breno S

2015-05-01

Previous studies suggest that executive functions influence the performance on visuoconstructional tasks. This study aims to investigate whether the relationship between planning ability and the copy of complex figures is mediated by distinct components of executive functions (i.e., working memory, inhibitory control and cognitive flexibility). We included a 129 older adults with Alzheimer's disease (n=36, AD), mild cognitive impairment (MCI, n=67), and with no evidence of cognitive impairment (controls, n=26). We evaluated the mediation effect of planning abilities, working memory, cognitive flexibility and inhibitory control on visuoconstructional tasks using a multiple mediation models. We found a significant direct effect of planning on visuoconstructional abilities and a partial mediation effect of working memory and cognitive flexibility on visuoconstructional abilities. The present results indicate that the performance on visuoconstructional task is mediated by multiple interrelated executive functions components, in particular working memory and cognitive flexibility.

Dopamine modulation of GABAergic function enables network stability and input selectivity for sustaining working memory in a computational model of the prefrontal cortex.

PubMed

Lew, Sergio E; Tseng, Kuei Y

2014-12-01

Dopamine modulation of GABAergic transmission in the prefrontal cortex (PFC) is thought to be critical for sustaining cognitive processes such as working memory and decision-making. Here, we developed a neurocomputational model of the PFC that includes physiological features of the facilitatory action of dopamine on fast-spiking interneurons to assess how a GABAergic dysregulation impacts on the prefrontal network stability and working memory. We found that a particular non-linear relationship between dopamine transmission and GABA function is required to enable input selectivity in the PFC for the formation and retention of working memory. Either degradation of the dopamine signal or the GABAergic function is sufficient to elicit hyperexcitability in pyramidal neurons and working memory impairments. The simulations also revealed an inverted U-shape relationship between working memory and dopamine, a function that is maintained even at high levels of GABA degradation. In fact, the working memory deficits resulting from reduced GABAergic transmission can be rescued by increasing dopamine tone and vice versa. We also examined the role of this dopamine-GABA interaction for the termination of working memory and found that the extent of GABAergic excitation needed to reset the PFC network begins to occur when the activity of fast-spiking interneurons surpasses 40 Hz. Together, these results indicate that the capability of the PFC to sustain working memory and network stability depends on a robust interplay of compensatory mechanisms between dopamine tone and the activity of local GABAergic interneurons.

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

PubMed

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

2017-01-25

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

A cross-sectional study of the demographic, cultural, clinical and rehabilitation associated variables predicting return to employment after disability onset in an Asian society.

PubMed

Chan, Wai Yin; Chew, Natalie Jin Lin; Nasron, Leila Ilmami Binte; Fook-Chong, Stephanie Man Chung; Ng, Yee Sien

2012-01-01

This study examined the rate of return to work, and to find demographic, clinical and functional factors associated with successful re-employment after in-patient rehabilitation. We performed a cross-sectional cohort study of Singaporeans aged 15 and above who underwent inpatient rehabilitation in a Singapore hospital between 2000 and 2007. Phone interviews were conducted in 2007 to 2008, via a structured questionnaire to evaluate factors of return to work. Four hundred and eight patients met with the inclusion criteria, and 123 participants completed the questionnaire. Forty-five (44.7%) participants successfully returned to work with a mean time of 7 months post-discharge. Statistical significant differences were found between the "return to work" group and "non-return to work" group based on age group (p=0.04), education level (p=0.001), pre-morbid job category (0.013) and functional status (p<0.0005) as determined by Functional Independence Measure scores. Cox regression analysis controlling the period between discharge and survey indicated that higher FIM scores and higher education level predicted successful re-employment. This result re-affirmed the importance of functional status to the success of return-to-work in Singapore. Further qualitative studies might be useful in exploring the social or environmental factors affecting return-to-work outcomes.

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

PubMed

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.

Working memory circuit as a function of increasing age in healthy adolescence: A systematic review and meta-analyses.

PubMed

Andre, Julia; Picchioni, Marco; Zhang, Ruibin; Toulopoulou, Timothea

2016-01-01

Working memory ability matures through puberty and early adulthood. Deficits in working memory are linked to the risk of onset of neurodevelopmental disorders such as schizophrenia, and there is a significant temporal overlap between the peak of first episode psychosis risk and working memory maturation. In order to characterize the normal working memory functional maturation process through this critical phase of cognitive development we conducted a systematic review and coordinate based meta-analyses of all the available primary functional magnetic resonance imaging studies (n = 382) that mapped WM function in healthy adolescents (10-17 years) and young adults (18-30 years). Activation Likelihood Estimation analyses across all WM tasks revealed increased activation with increasing subject age in the middle frontal gyrus (BA6) bilaterally, the left middle frontal gyrus (BA10), the left precuneus and left inferior parietal gyri (BA7; 40). Decreased activation with increasing age was found in the right superior frontal (BA8), left junction of postcentral and inferior parietal (BA3/40), and left limbic cingulate gyrus (BA31). These results suggest that brain activation during adolescence increased with age principally in higher order cortices, part of the core working memory network, while reductions were detected in more diffuse and potentially more immature neural networks. Understanding the process by which the brain and its cognitive functions mature through healthy adulthood may provide us with new clues to understanding the vulnerability to neurodevelopmental disorders.

Long working hours and cognitive function: the Whitehall II Study.

PubMed

Virtanen, Marianna; Singh-Manoux, Archana; Ferrie, Jane E; Gimeno, David; Marmot, Michael G; Elovainio, Marko; Jokela, Markus; Vahtera, Jussi; Kivimäki, Mika

2009-03-01

This study examined the association between long working hours and cognitive function in middle age. Data were collected in 1997-1999 (baseline) and 2002-2004 (follow-up) from a prospective study of 2,214 British civil servants who were in full-time employment at baseline and had data on cognitive tests and covariates. A battery of cognitive tests (short-term memory, Alice Heim 4-I, Mill Hill vocabulary, phonemic fluency, and semantic fluency) were measured at baseline and at follow-up. Compared with working 40 hours per week at most, working more than 55 hours per week was associated with lower scores in the vocabulary test at both baseline and follow-up. Long working hours also predicted decline in performance on the reasoning test (Alice Heim 4-I). Similar results were obtained by using working hours as a continuous variable; the associations between working hours and cognitive function were robust to adjustments for several potential confounding factors including age, sex, marital status, education, occupation, income, physical diseases, psychosocial factors, sleep disturbances, and health risk behaviors. This study shows that long working hours may have a negative effect on cognitive performance in middle age.

Long Working Hours and Cognitive Function

PubMed Central

Singh-Manoux, Archana; Ferrie, Jane E.; Gimeno, David; Marmot, Michael G.; Elovainio, Marko; Jokela, Markus; Vahtera, Jussi; Kivimäki, Mika

2009-01-01

This study examined the association between long working hours and cognitive function in middle age. Data were collected in 1997–1999 (baseline) and 2002–2004 (follow-up) from a prospective study of 2,214 British civil servants who were in full-time employment at baseline and had data on cognitive tests and covariates. A battery of cognitive tests (short-term memory, Alice Heim 4-I, Mill Hill vocabulary, phonemic fluency, and semantic fluency) were measured at baseline and at follow-up. Compared with working 40 hours per week at most, working more than 55 hours per week was associated with lower scores in the vocabulary test at both baseline and follow-up. Long working hours also predicted decline in performance on the reasoning test (Alice Heim 4-I). Similar results were obtained by using working hours as a continuous variable; the associations between working hours and cognitive function were robust to adjustments for several potential confounding factors including age, sex, marital status, education, occupation, income, physical diseases, psychosocial factors, sleep disturbances, and health risk behaviors. This study shows that long working hours may have a negative effect on cognitive performance in middle age. PMID:19126590

Intrinsic motivation as a predictor of work outcome after vocational rehabilitation in schizophrenia.

PubMed

Saperstein, Alice M; Fiszdon, Joanna M; Bell, Morris D

2011-09-01

Intrinsic motivation is a construct commonly used in explaining goal-directed behavior. In people with schizophrenia, intrinsic motivation is usually subsumed as a feature of negative symptoms or underlying neurocognitive dysfunction. A growing literature reflects an interest in defining and measuring motivational impairment in schizophrenia and in delineating the specific role of intrinsic motivation as both an independent predictor and a mediator of psychosocial functioning. This cross-sectional study examined intrinsic motivation as a predictor of vocational outcomes for 145 individuals with schizophrenia and schizoaffective disorder participating in a 6-month work rehabilitation trial. Correlation and mediation analyses examined baseline intrinsic motivation and negative symptoms in relation to work hours and work performance. Data support a significant relationship between intrinsic motivation and negative symptoms and significant correlations with outcome variables, such that lower negative symptoms and greater intrinsic motivation were associated with better work functioning. Moreover, in this sample, intrinsic motivation fully mediated the relationships between negative symptoms, work productivity, and work performance. These results have significant implications on the design of work rehabilitation interventions for people with schizophrenia and support a role for targeting intrinsic motivation directly to influence vocational functioning. Future directions for research and intervention are discussed.

The default mode network and the working memory network are not anti-correlated during all phases of a working memory task.

PubMed

Piccoli, Tommaso; Valente, Giancarlo; Linden, David E J; Re, Marta; Esposito, Fabrizio; Sack, Alexander T; Di Salle, Francesco

2015-01-01

The default mode network and the working memory network are known to be anti-correlated during sustained cognitive processing, in a load-dependent manner. We hypothesized that functional connectivity among nodes of the two networks could be dynamically modulated by task phases across time. To address the dynamic links between default mode network and the working memory network, we used a delayed visuo-spatial working memory paradigm, which allowed us to separate three different phases of working memory (encoding, maintenance, and retrieval), and analyzed the functional connectivity during each phase within and between the default mode network and the working memory network networks. We found that the two networks are anti-correlated only during the maintenance phase of working memory, i.e. when attention is focused on a memorized stimulus in the absence of external input. Conversely, during the encoding and retrieval phases, when the external stimulation is present, the default mode network is positively coupled with the working memory network, suggesting the existence of a dynamically switching of functional connectivity between "task-positive" and "task-negative" brain networks. Our results demonstrate that the well-established dichotomy of the human brain (anti-correlated networks during rest and balanced activation-deactivation during cognition) has a more nuanced organization than previously thought and engages in different patterns of correlation and anti-correlation during specific sub-phases of a cognitive task. This nuanced organization reinforces the hypothesis of a direct involvement of the default mode network in cognitive functions, as represented by a dynamic rather than static interaction with specific task-positive networks, such as the working memory network.

The Default Mode Network and the Working Memory Network Are Not Anti-Correlated during All Phases of a Working Memory Task

PubMed Central

Piccoli, Tommaso; Valente, Giancarlo; Linden, David E. J.; Re, Marta; Esposito, Fabrizio; Sack, Alexander T.; Salle, Francesco Di

2015-01-01

Introduction The default mode network and the working memory network are known to be anti-correlated during sustained cognitive processing, in a load-dependent manner. We hypothesized that functional connectivity among nodes of the two networks could be dynamically modulated by task phases across time. Methods To address the dynamic links between default mode network and the working memory network, we used a delayed visuo-spatial working memory paradigm, which allowed us to separate three different phases of working memory (encoding, maintenance, and retrieval), and analyzed the functional connectivity during each phase within and between the default mode network and the working memory network networks. Results We found that the two networks are anti-correlated only during the maintenance phase of working memory, i.e. when attention is focused on a memorized stimulus in the absence of external input. Conversely, during the encoding and retrieval phases, when the external stimulation is present, the default mode network is positively coupled with the working memory network, suggesting the existence of a dynamically switching of functional connectivity between “task-positive” and “task-negative” brain networks. Conclusions Our results demonstrate that the well-established dichotomy of the human brain (anti-correlated networks during rest and balanced activation-deactivation during cognition) has a more nuanced organization than previously thought and engages in different patterns of correlation and anti-correlation during specific sub-phases of a cognitive task. This nuanced organization reinforces the hypothesis of a direct involvement of the default mode network in cognitive functions, as represented by a dynamic rather than static interaction with specific task-positive networks, such as the working memory network. PMID:25848951

Hexagonalization of correlation functions II: two-particle contributions

NASA Astrophysics Data System (ADS)

Fleury, Thiago; Komatsu, Shota

2018-02-01

In this work, we compute one-loop planar five-point functions in N=4 super-Yang-Mills using integrability. As in the previous work, we decompose the correlation functions into hexagon form factors and glue them using the weight factors which depend on the cross-ratios. The main new ingredient in the computation, as compared to the four-point functions studied in the previous paper, is the two-particle mirror contribution. We develop techniques to evaluate it and find agreement with the perturbative results in all the cases we analyzed. In addition, we consider next-to-extremal four-point functions, which are known to be protected, and show that the sum of one-particle and two-particle contributions at one loop adds up to zero as expected. The tools developed in this work would be useful for computing higher-particle contributions which would be relevant for more complicated quantities such as higher-loop corrections and non-planar correlators.

The effect of Al segregation on Schottky barrier height and effective work function in TiAl/TiN/HfO2 gate stacks

NASA Astrophysics Data System (ADS)

Kim, Geun-Myeong; Oh, Young Jun; Chang, K. J.

2016-07-01

We perform first-principles density functional calculations to investigate the effects of Al incorporation on the p-type Schottky barrier height ≤ft({φ\\text{p}}\\right) and the effective work function for various high-k/metal gate stacks, such as TiN/HfO2 with interface Al impurities, Ti1-x Al x N/HfO2, and TiAl/TiN/HfO2. When Al atoms substitute for the interface Ti atoms at TiN/HfO2 interface, interface dipole fields become stronger, leading to the increase of {φ\\text{p}} and thereby the n-type shift of effective work function. In Ti1-x Al x N/HfO2 interface, {φ\\text{p}} linearly increases with the Al content, attributed to the presence of interface Al atoms. On the other hand, in TiAl/TiN/HfO2 interface, where Al is assumed not to segregate from TiAl to TiN, {φ\\text{p}} is nearly independent of the thickness of TiAl. Our results indicate that Al impurities at the metal/dielectric interface play an important role in controlling the effective work function, and provide a clue to understanding the n-type shift of the effective work function observed in TiAl/TiN/HfO2 gate stacks fabricated by using thegate-last process.

Effects of Ganglioside on Working Memory and the Default Mode Network in Individuals with Subjective Cognitive Impairment: A Randomized Controlled Trial.

PubMed

Jeon, Yujin; Kim, Binna; Kim, Jieun E; Kim, Bori R; Ban, Soonhyun; Jeong, Jee Hyang; Kwon, Oran; Rhie, Sandy Jeong; Ahn, Chang-Won; Kim, Jong-Hoon; Jung, Sung Ug; Park, Soo-Hyun; Lyoo, In Kyoon; Yoon, Sujung

2016-01-01

This randomized, double-blind, placebo-controlled trial examined whether the administration of ganglioside, an active ingredient of deer bone extract, can improve working memory performance by increasing gray matter volume and functional connectivity in the default mode network (DMN) in individuals with subjective cognitive impairment. Seventy-five individuals with subjective cognitive impairment were chosen to receive either ganglioside (330[Formula: see text][Formula: see text]g/day or 660[Formula: see text][Formula: see text]g/day) or a placebo for 8 weeks. Changes in working memory performance with treatment of either ganglioside or placebo were assessed as cognitive outcome measures. Using voxel-based morphometry and functional connectivity analyses, changes in gray matter volume and functional connectivity in the DMN were also assessed as brain outcome measures. Improvement in working memory performance was greater in the ganglioside group than in the placebo group. The ganglioside group, relative to the placebo group, showed greater increases in gray matter volume and functional connectivity in the DMN. A significant relationship between increased functional connectivity of the precuneus and improved working memory performance was observed in the ganglioside group. The current findings suggest that ganglioside has cognitive-enhancing effects in individuals with subjective cognitive impairment. Ganglioside-induced increases in gray matter volume and functional connectivity in the DMN may partly be responsible for the potential nootropic effects of ganglioside. The clinical trial was registered with ClinicalTrials.gov (identifier: NCT02379481).

Assessment and treatment of short-term and working memory impairments in stroke aphasia: a practical tutorial.

PubMed

Salis, Christos; Kelly, Helen; Code, Chris

2015-01-01

Aphasia following stroke refers to impairments that affect the comprehension and expression of spoken and/or written language, and co-occurring cognitive deficits are common. In this paper we focus on short-term and working memory impairments that impact on the ability to retain and manipulate auditory-verbal information. Evidence from diverse paradigms (large group studies, case studies) report close links between short-term/working memory and language functioning in aphasia. This evidence leads to the hypothesis that treating such memory impairments would improve language functioning. This link has only recently been acknowledged in aphasia treatment but has not been embraced widely by clinicians. To examine the association between language, and short-term and working memory impairments in aphasia. To describe practical ways of assessing short-term and working memory functioning that could be used in clinical practice. To discuss and critically appraise treatments of short-term and working memory reported in the literature. Taking a translational research approach, this paper provides clinicians with current evidence from the literature and practical information on how to assess and treat short-term and working memory impairments in people with aphasia. Published treatments of short-term and/or working memory in post-stroke aphasia are discussed through a narrative review. This paper provides the following. A theoretical rationale for adopting short-term and working memory treatments in aphasia. It highlights issues in differentially diagnosing between short-term, working memory disorders and other concomitant impairments, e.g. apraxia of speech. It describes short-term and working memory assessments with practical considerations for use with people with aphasia. It also offers a description of published treatments in terms of participants, treatments and outcomes. Finally, it critically appraises the current evidence base relating to the treatment of short-term and working memory treatments. The links between short-term/working memory functioning and language in aphasia are generally acknowledged. These strongly indicate the need to incorporate assessment of short-term/working memory functioning for people with aphasia. While the supportive evidence for treatment is growing and appears to highlight the benefits of including short-term/working memory in aphasia treatment, the quality of the evidence in its current state is poor. However, because of the clinical needs of people with aphasia and the prevalence of short-term/working memory impairments, incorporating related treatments through practice-based evidence is advocated. © 2015 Royal College of Speech and Language Therapists.

Successful Aging in the Context of the Disablement Process: Working and Volunteering as Moderators on the Association Between Chronic Conditions and Subsequent Functional Limitations.

PubMed

Kail, Ben Lennox; Carr, Dawn C

2017-03-01

This study evaluated the successful aging model by assessing the impact of two forms of productive engagement-working and volunteering-as potential interventions in the process of disablement. The Health and Retirement Study was used to (a) estimate two-stage selection equations of (i) currently working part time and full time and (ii) currently volunteering less than 100 hours and volunteering 100 hours or more per year (net of chronic health problems) and (b) assess whether, net of selection, working, and volunteering moderate the association between chronic conditions and subsequent functional limitations. Chronic conditions were associated with elevated levels of subsequent functional limitations, whereas both working and volunteering were associated with lower levels of subsequent functional limitations. Moreover, workers and volunteers of less than 100 hours per year experienced a reduction in the association of chronic conditions on subsequent functional limitations. This research highlights the role of productive engagement as a key element in successful aging. Not only do work and volunteering have direct associations with health outcomes themselves, but they also act as potential interventions in the process of disablement by attenuating the way in which chronic conditions are translated into subsequent functional limitations. This suggests that (a) future research should apply successful aging models to health processes as well as health outcomes and (b) policy makers should support social institutions that foster late-life productive engagement. © The Author 2016. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Evaluation of the measurement properties of self-reported health-related work-functioning instruments among workers with common mental disorders.

PubMed

Abma, Femke I; van der Klink, Jac J L; Terwee, Caroline B; Amick, Benjamin C; Bültmann, Ute

2012-01-01

During the past decade, common mental disorders (CMD) have emerged as a major public and occupational health problem in many countries. Several instruments have been developed to measure the influence of health on functioning at work. To select appropriate instruments for use in occupational health practice and research, the measurement properties (eg, reliability, validity, responsiveness) must be evaluated. The objective of this study is to appraise critically and compare the measurement properties of self-reported health-related work-functioning instruments among workers with CMD. A systematic review was performed searching three electronic databases. Papers were included that: (i) mainly focused on the development and/or evaluation of the measurement properties of a self-reported health-related work-functioning instrument; (ii) were conducted in a CMD population; and (iii) were fulltext original papers. Quality appraisal was performed using the consensus-based standards for the selection of health status measurement instruments (COSMIN) checklist. Five papers evaluating measurement properties of five self-reported health-related work-functioning instruments in CMD populations were included. There is little evidence available for the measurement properties of the identified instruments in this population, mainly due to low methodological quality of the included studies. The available evidence on measurement properties is based on studies of poor-to-fair methodological quality. Information on a number of measurement properties, such as measurement error, content validity, and cross-cultural validity is still lacking. Therefore, no evidence-based decisions and recommendations can be made for the use of health-related work functioning instruments. Studies of high methodological quality are needed to properly assess the existing instruments' measurement properties.

Efficiency of Cs-free materials for negative ion production in H2 and D2 plasmas

NASA Astrophysics Data System (ADS)

Friedl, R.; Kurutz, U.; Fantz, U.

2017-08-01

High power negative ion sources use caesium to reduce the work function of the converter surface which significantly increases the negative ion yield. Caesium, however, is a very reactive alkali-metal and shows complex redistribution dynamics in consequence of plasma-surface-interaction. Thus, maintaining a stable and homogenous low work function surface is a demanding task, which is not easily compatible with the RAMI issues (reliability, availability, maintainability, inspectability) for a future DEMO fusion reactor. Hence, Cs-free alternative materials for efficient negative ion formation are desirable. At the laboratory experiment HOMER materials which are referred to as promising are investigated under identical and ion source relevant parameters: the refractory metals Ta and W, non-doped and boron-doped diamond as well as materials with inherent low work function (lanthanum-doped molybdenum, MoLa and lanthanum hexaboride, LaB6). The results are compared to the effect of in-situ caesiation, which at HOMER leads to a maximal increase of the negative ion density by a factor of 2.5. Among the examined samples low work function materials are most efficient. In particular, MoLa leads to an increase of almost 50 % compared to pure volume formation. The difference to a caesiated surface can be attributed to the still higher work function of MoLa, which is expected to be slightly below 3 eV. Using deuterium instead of hydrogen leads to increased atomic and positive ion densities, while comparable negative ion densities are achieved. In contrast to the low work function materials, bulk samples of the refractory metals as well as carbon based materials have no enhancing effect on H-, where the latter materials furthermore show severe erosion due to the hydrogen plasma.

Relation of Cognitive Measures to Perceived Work Limitations in Cancer Survivors

DTIC Science & Technology

2009-11-30

completed measures of symptom burden, cognitive function and perceived work output. Results: Breast cancer survivors were an average 3.1 years post ... post -treatment. Self report of cognitive function was significantly related to work output (R2 change = 0.298, p < 0.001) while performance measures...Symptom burden: BCS (N=122) and NCCG (N=112) ...................................... 37 Table 5: Relationship between performance test scales and self

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

PubMed

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.

How a submarine returns to periscope depth: analysing complex socio-technical systems using Cognitive Work Analysis.

PubMed

Stanton, Neville A; Bessell, Kevin

2014-01-01

This paper presents the application of Cognitive Work Analysis to the description of the functions, situations, activities, decisions, strategies, and competencies of a Trafalgar class submarine when performing the function of returning to periscope depth. All five phases of Cognitive Work Analysis are presented, namely: Work Domain Analysis, Control Task Analysis, Strategies Analysis, Social Organisation and Cooperation Analysis, and Worker Competencies Analysis. Complex socio-technical systems are difficult to analyse but Cognitive Work Analysis offers an integrated way of analysing complex systems with the core of functional means-ends analysis underlying all of the other representations. The joined-up analysis offers a coherent framework for understanding how socio-technical systems work. Data were collected through observation and interviews at different sites across the UK. The resultant representations present a statement of how the work domain and current activities are configured in this complex socio-technical system. This is intended to provide a baseline, from which all future conceptions of the domain may be compared. The strength of the analysis is in the multiple representations from which the constraints acting on the work may be analysed. Future research needs to challenge the assumptions behind these constraints in order to develop new ways of working. Copyright © 2013 Elsevier Ltd and The Ergonomics Society. All rights reserved.

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

PubMed

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.

[Model Foundation S. Maugeri-IRCCS].

PubMed

Bazzini, G

2010-01-01

A multidisciplinary (physiatrist, occupational physician, neurophysiologist, radiologist, etc.) and multiprofessional (occupational therapist, physiotherapist, ergonomist) strategy for rehabilitation and re-introduction of people with work-related injuries was tested at the "Fondazione Maugeri" Scientific Institue (Pavia, Italy). This process of re-introduction to work has several stages including increasing strength and resistance, specific occupational therapy activities to recover working functions and movements, aerobic training, prescription and allocation of any auxiliaries necessary, and inspections of the home and workplace. One particular feature is the final functional evaluation, whose aims are: to study the subject's "residual capacities" and "sustainable capacities", to supply useful information to the occupational physician in view of the verifying the patient's suitability for work, to contribute to "targeted" re-introduction, and to offer parameters useful for prevention and ergonomic planning. The main features of the disabled person which are studied are: degree of disability, motor capacity (joint movements, strength, resistance), cognitive-verbal functions, sensitivity and sensory functions, psychological and emotional components, need for auxiliaries, educational-professional aspects, possibility of autonomous transport, and motivation.

Structural variations in prefrontal cortex mediate the relationship between early childhood stress and spatial working memory

PubMed Central

Hanson, Jamie L.; Chung, Moo K.; Avants, Brian B.; Rudolph, Karen D.; Shirtcliff, Elizabeth A.; Gee, James C.; Davidson, Richard J.; Pollak, Seth D.

2012-01-01

A large corpus of research indicates exposure to stress impairs cognitive abilities, specifically executive functioning dependent on the prefrontal cortex (PFC). We collected structural MRI scans (n=61), well-validated assessments of executive functioning, and detailed interviews assessing stress exposure in humans, to examine whether cumulative life stress affected brain morphometry and one type of executive functioning, spatial working memory, during adolescence—a critical time of brain development and reorganization. Analysis of variations in brain structure revealed that cumulative life stress and spatial working memory were related to smaller volumes in the PFC, specifically prefrontal gray and white matter between the anterior cingulate and the frontal poles. Mediation analyses revealed that individual differences in prefrontal volumes accounted for the association between cumulative life stress and spatial working memory. These results suggest that structural changes in the PFC may serve as a mediating mechanism through which greater cumulative life stress engenders decrements in cognitive functioning. PMID:22674267

[Gender influence on health related quality of life among resident physicians working in an emergency department].

PubMed

Fernández-Prada, María; González-Cabrera, Joaquín; Torres G, Francisco; Iribar-Ibabe, Concepción; María Peinado, José

2014-02-01

The high emotional burden of physicians working in emergency departments may affect their quality of life perception. To evaluate health related quality of life among resident physicians performing shifts at an emergency department. Seventy one physicians aged 26,3 ± 1,7 years (47 women), working as residents in an emergency department, answered the short version of the Short-Form Health Survey Questionnaire (SF-36®). This questionnaire analyses eight domains: physical function, body pain, general health, vitality, social function, emotional role and mental health. Women had a significantly worse perception than a reference population in four dimensions of the SF-36, especially mental health and social functioning. Men had scores similar to the reference population. Among women, vitality is the best predictor of mental health and social functioning. Women working as residents in an emergency department have a worse perception of their quality of life than men performing the same job.

Work function of bulk-insulating topological insulator Bi{sub 2–x}Sb{sub x}Te{sub 3–y}Se{sub y}

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

Takane, Daichi; Souma, Seigo; Center for Spintronics Research Network, Tohoku University, Sendai 980-8577

Recent discovery of bulk insulating topological insulator (TI) Bi{sub 2–x}Sb{sub x}Te{sub 3–y}Se{sub y} paved a pathway toward practical device application of TIs. For realizing TI-based devices, it is necessary to contact TIs with a metal. Since the band-bending at the interface dominates the character of devices, knowledge of TIs' work function is of essential importance. We have determined the compositional dependence of the work function in Bi{sub 2–x}Sb{sub x}Te{sub 3–y}Se{sub y} by high-resolution photoemission spectroscopy. The obtained work-function values (4.95–5.20 eV) track the energy shift of the surface chemical potential seen by angle-resolved photoemission spectroscopy. The present result serves as amore » useful guide for developing TI-based electronic devices.« less

Improved performance of nanoscale junctionless tunnel field-effect transistor based on gate engineering approach

NASA Astrophysics Data System (ADS)

Molaei Imen Abadi, Rouzbeh; Sedigh Ziabari, Seyed Ali

2016-11-01

In this paper, a first qualitative study on the performance characteristics of dual-work function gate junctionless TFET (DWG-JLTFET) on the basis of energy band profile modulation is investigated. A dual-work function gate technique is used in a JLTFET in order to create a downward band bending on the source side similar to PNPN structure. Compared with the single-work function gate junctionless TFET (SWG-JLTFET), the numerical simulation results demonstrated that the DWG-JLTFET simultaneously optimizes the ON-state current, the OFF-state leakage current, and the threshold voltage and also improves average subthreshold slope. It is illustrated that if appropriate work functions are selected for the gate materials on the source side and the drain side, the JLTFET exhibits a considerably improved performance. Furthermore, the optimization design of the tunnel gate length ( L Tun) for the proposed DWG-JLTFET is studied. All the simulations are done in Silvaco TCAD for a channel length of 20 nm using the nonlocal band-to-band tunneling (BTBT) model.

Photoinduced work function changes by isomerization of a densely packed azobenzene-based SAM on Au: a joint experimental and theoretical study.

PubMed

Crivillers, N; Liscio, A; Di Stasio, F; Van Dyck, C; Osella, S; Cornil, D; Mian, S; Lazzerini, G M; Fenwick, O; Orgiu, E; Reinders, F; Braun, S; Fahlman, M; Mayor, M; Cornil, J; Palermo, V; Cacialli, F; Samorì, P

2011-08-28

Responsive monolayers are key building blocks for future applications in organic and molecular electronics in particular because they hold potential for tuning the physico-chemical properties of interfaces, including their energetics. Here we study a photochromic SAM based on a conjugated azobenzene derivative and its influence on the gold work function (Φ(Au)) when chemisorbed on its surface. In particular we show that the Φ(Au) can be modulated with external stimuli by controlling the azobenzene trans/cis isomerization process. This phenomenon is characterized experimentally by four different techniques, kelvin probe, kelvin probe force microscopy, electroabsorption spectroscopy and ultraviolet photoelectron spectroscopy. The use of different techniques implies exposing the SAM to different measurement conditions and different preparation methods, which, remarkably, do not alter the observed work function change (Φ(trans)-Φ(cis)). Theoretical calculations provided a complementary insight crucial to attain a deeper knowledge on the origin of the work function photo-modulation.

Functional-Based Resection Does Not Worsen Quality of Life in Patients with a Diffuse Low-Grade Glioma Involving Eloquent Brain Regions: A Prospective Cohort Study.

PubMed

Muto, Jun; Dezamis, Edouard; Rigaux-Viode, Odile; Peeters, Sophie; Roux, Alexandre; Zanello, Marc; Mellerio, Charles; Sauvageon, Xavier; Varlet, Pascale; Oppenheim, Catherine; Pallud, Johan

2018-05-01

We assessed the impact of surgery on postoperative cognitive function and ability to work in adult patients with a diffuse low-grade glioma involving eloquent brain regions and having a functional-based maximal surgical resection using intraoperative corticosubcortical mapping under awake conditions. We prospectively included 39 consecutive patients with diffuse isocitrate dehydrogenase-mutant low-grade glioma without preoperative and adjuvant oncologic treatment and assessed preoperative (mean, 24.1 ± 21.2 days before surgery) and postoperative (mean, 14.6 ± 13.2 months after surgery) cognitive evaluations and ability to work together with clinical, imaging, therapeutic, and follow-up characteristics before tumor progression. None of the 3 patients without preoperative cognitive deficit had postoperative worsening. We observed a significant inverse interaction between worsened postoperative cognitive function and extent of resection: 80.0%, 18.8%, and 16.7% of worsening after partial, subtotal, and total resection, respectively (P = 0.020). We observed an independent interaction between improved postoperative cognitive function and extent of resection: 20.0%, 43.7%, and 44.4% of improvement after partial, subtotal, and total resection, respectively (P = 0.022). Of the employed patients, 61.8% were unable to work preoperatively and 82.4% resumed their employment postoperatively (mean, 6.9 ± 5.5 months). We observed an independent interaction between postoperative ability to work, similar or superior to preoperative work capacity and extent of resection (P < 0.001): 20.0%, 87.5%, and 100% ability to work after partial, subtotal resection, and total resection. The extent of the functional-based surgical resection and the residual tumor for diffuse low-grade gliomas involving eloquent brain regions correlate with postoperative cognitive outcomes and return to work rates. Copyright © 2018 Elsevier Inc. All rights reserved.

Perceived cognitive function in coronary artery disease--an unrecognised predictor of unemployment.

PubMed

Kiessling, Anna; Henriksson, Peter

2005-08-01

We aimed to assess whether perceived cognitive function influences employment and return to work in patients with coronary artery disease (CAD). Prospective longitudinal cohort study. Health care system of Södertälje, Stockholm County, Sweden. We included consecutive unselected patients less than 65 years of age with CAD and followed them during 2 years. Gainful employment and return to work in patients with CAD. We found that perceived cognitive function predicts both prevalence of unemployment [OR 2.06 (95% CI: 1.36-3.13); p = 0.0006] and early retirement and sick leave due to coronary artery disease [OR 1.59 (95% CI: 1.12-2.25)] both at baseline and 2 years later. Furthermore, perceived cognitive function predicted return to work after an acute coronary event [OR 2.28 (95% CI: 1.08-4.84)]. Covariates such as age, sex, prevalence and degree of angina (CCS grade), cardiovascular risk factors and events did not change the predictive power. Perceived cognitive function is a hitherto unrecognised independent predictor of unemployment, sick leave and return to work in patients with coronary artery disease. Perceived cognitive function adds a new perspective on ability to gainful employment in patients with CAD. The findings might have significance both to individual care and to society.

Reciprocal Relations between Work-Related Authenticity and Intrinsic Motivation, Work Ability and Depressivity: A Two-Wave Study.

PubMed

Emmerich, Astrid I; Rigotti, Thomas

2017-01-01

This study investigates the role of context-specific authenticity at work for work-related outcomes (intrinsic motivation, work ability) and depressivity. Furthermore reciprocal relations between work-related authenticity and healthy psychological functioning are investigated. Longitudinal data from 1,243 employees from 63 subsidiaries of a non-profit organization in the social sector were analyzed using multilevel structural equation modeling. Work-related authenticity at T1 predicted work ability and depressivity, but not intrinsic motivation at T2, about 6 months later. Work-related authenticity at T2 was predicted by intrinsic motivation and depressivity, but not by work ability at T1. We conclude that work-related authenticity and healthy psychological functioning are positively reinforcing each other. Thus, enabling employees to be authentic supposedly increases their well-being and is a pivotal opportunity for organizations to foster health and performance-related indicators like work ability and prevent negative health indicators like depressivity. At the same time, authenticity of employees can be fostered through workplace health promotion.

Significant vertical phase separation in solvent-vapor-annealed poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) composite films leading to better conductivity and work function for high-performance indium tin oxide-free optoelectronics.

PubMed

Yeo, Jun-Seok; Yun, Jin-Mun; Kim, Dong-Yu; Park, Sungjun; Kim, Seok-Soon; Yoon, Myung-Han; Kim, Tae-Wook; Na, Seok-In

2012-05-01

In the present study, a novel polar-solvent vapor annealing (PSVA) was used to induce a significant structural rearrangement in poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) films in order to improve their electrical conductivity and work function. The effects of polar-solvent vapor annealing on PEDOT:PSS were systematically compared with those of a conventional solvent additive method (SAM) and investigated in detail by analyzing the changes in conductivity, morphology, top and bottom surface composition, conformational PEDOT chains, and work function. The results confirmed that PSVA induces significant phase separation between excess PSS and PEDOT chains and a spontaneous formation of a highly enriched PSS layer on the top surface of the PEDOT:PSS polymer blend, which in turn leads to better 3-dimensional connections between the conducting PEDOT chains and higher work function. The resultant PSVA-treated PEDOT:PSS anode films exhibited a significantly enhanced conductivity of up to 1057 S cm(-1) and a tunable high work function of up to 5.35 eV. The PSVA-treated PEDOT:PSS films were employed as transparent anodes in polymer light-emitting diodes (PLEDs) and polymer solar cells (PSCs). The cell performances of organic optoelectronic devices with the PSVA-treated PEDOT:PSS anodes were further improved due to the significant vertical phase separation and the self-organized PSS top surface in PSVA-treated PEDOT:PSS films, which can increase the anode conductivity and work function and allow the direct formation of a functional buffer layer between the active layer and the polymeric electrode. The results of the present study will allow better use and understanding of polymeric-blend materials and will further advance the realization of high-performance indium tin oxide (ITO)-free organic electronics.

Implementing structured functional assessments in general practice for persons with long-term sick leave: a cluster randomised controlled trial.

PubMed

Østerås, Nina; Gulbrandsen, Pål; Benth, Jūrate Saltyte; Hofoss, Dag; Brage, Søren

2009-05-06

The increasing attention on functional assessments in medical and vocational rehabilitation requires a focus change for the general practitioners (GP) into paying attention to patient resources, possibilities and coping instead of symptoms, problems and limitations. The GPs report difficulties in performing the requested explicit functional assessments. The purpose of this study was to implement a structured method in general practice for assessing functional ability in persons with long-term sick leave. The study aim was to evaluate intervention effects on important GP parameters; knowledge, attitudes, self-efficacy towards functional assessments and knowledge about patient work factors. Fifty-seven GPs were randomly assigned to an intervention or a control group. The intervention group GPs attended an introductory one-day work-shop and implemented structured functional assessments during an eight months intervention period. GP knowledge, GP attitudes, and GP self-efficacy towards functional assessments, as well as GP knowledge of patient work factors, were collected before, after and six months after the intervention period started. Evaluation score-sheets were filled in by both the intervention GPs and their patients immediately after the consultation to evaluate the GPs' knowledge of patient work factors. The intervention GPs reported increased knowledge (B: 0.56, 95% CI (0.19, 0.91)) and self-efficacy (B: 0.90, 95% CI (0.53, 1.26)) towards functional assessments, and increased knowledge about their patients' workplace (B: 0.75, 95% CI (0.35, 1.15)) and perceived stressors (B: 0.55, 95% CI (0.23, 0.88)) with lasting effects at the second follow-up. No intervention effect was seen in relation to GP attitudes. Both before and after the intervention, the GPs were most informed about physical stressors, and less about mental and work organisational stressors (Guttman's reproducibility coefficient: 0.95 and 1.00). After the consultation, both the intervention GPs and their patients reported that the GPs' knowledge about patient work factors had increased (GP B: 0.60 (95% CI: 0.42, 0.78); patient B: 0.50 (95% CI: 0.34, 0.66)). Introducing and implementing structured functional assessments in general practice made the GPs capable to assess functional ability of their patients in a structured manner. Intervention effects of increased GP knowledge and GP self-efficacy sustained at the second follow-up.

New Basis Functions for the Electromagnetic Solution of Arbitrarily-shaped, Three Dimensional Conducting Bodies Using Method of Moments

NASA Technical Reports Server (NTRS)

Mackenzie, Anne I.; Baginski, Michael E.; Rao, Sadasiva M.

2007-01-01

In this work, we present a new set of basis functions, de ned over a pair of planar triangular patches, for the solution of electromagnetic scattering and radiation problems associated with arbitrarily-shaped surfaces using the method of moments solution procedure. The basis functions are constant over the function subdomain and resemble pulse functions for one and two dimensional problems. Further, another set of basis functions, point-wise orthogonal to the first set, is also de ned over the same function space. The primary objective of developing these basis functions is to utilize them for the electromagnetic solution involving conducting, dielectric, and composite bodies. However, in the present work, only the conducting body solution is presented and compared with other data.

New Basis Functions for the Electromagnetic Solution of Arbitrarily-shaped, Three Dimensional Conducting Bodies using Method of Moments

NASA Technical Reports Server (NTRS)

Mackenzie, Anne I.; Baginski, Michael E.; Rao, Sadasiva M.

2008-01-01

In this work, we present a new set of basis functions, defined over a pair of planar triangular patches, for the solution of electromagnetic scattering and radiation problems associated with arbitrarily-shaped surfaces using the method of moments solution procedure. The basis functions are constant over the function subdomain and resemble pulse functions for one and two dimensional problems. Further, another set of basis functions, point-wise orthogonal to the first set, is also defined over the same function space. The primary objective of developing these basis functions is to utilize them for the electromagnetic solution involving conducting, dielectric, and composite bodies. However, in the present work, only the conducting body solution is presented and compared with other data.

Subjective health complaints, functional ability, fear avoidance beliefs, and days on sickness benefits after work rehabilitation - a mediation model.

PubMed

Øyeflaten, Irene; Opsahl, Jon; Eriksen, Hege R; Braathen, Tore Norendal; Lie, Stein Atle; Brage, Søren; Ihlebæk, Camilla M; Breivik, Kyrre

2016-05-23

Long-term sick leave and withdrawal from working life is a concern in western countries. In Norway, comprehensive inpatient work rehabilitation may be offered to sick listed individuals at risk of long-term absence from work. Knowledge about prognostic factors for work outcomes after long-term sick leave and work rehabilitation is still limited. The aim of this study was to test a mediation model for various hypothesized biopsychosocial predictors of continued sick leave after inpatient work rehabilitation. One thousand one hundred fifty-five participants on long-term sick leave from eight different work rehabilitation clinics answered comprehensive questionnaires at arrival to the clinic, and were followed with official register data on sickness benefits for 3 years. Structural equation models were conducted, with days on sickness benefits after work rehabilitation as the outcome. Fear avoidance beliefs for work mediated the relation between both musculoskeletal complaints and education on days on sickness benefits after work rehabilitation. The relation between musculoskeletal complaints and fear avoidance beliefs for work was furthermore fully mediated by poor physical function. Previous sick leave had a strong independent effect on continued sick leave after work rehabilitation. Fear avoidance beliefs for work did not mediate the small effect of pseudoneurological complaints on continued sick leave. Poor coping/interaction ability was neither related to continued sick leave nor fear avoidance beliefs for work. The mediation model was partly supported by the data, and provides some possible new insight into how fear avoidance beliefs for work and functional ability may intervene with subjective health complaints and days on sickness benefits after work rehabilitation.

Association between mental demands at work and cognitive functioning in the general population – results of the health study of the Leipzig research center for civilization diseases (LIFE)

PubMed Central

2014-01-01

Background The level of mental demands in the workplace is rising. The present study investigated whether and how mental demands at work are associated with cognitive functioning in the general population. Methods The analysis is based on data of the Health Study of the Leipzig Research Centre for Civilization Disease (LIFE). 2,725 participants aged 40–80 years underwent cognitive testing (Trail-Making Test, Verbal Fluency Test) and provided information on their occupational situation. Participants over the age of 65 years additionally completed the Mini-Mental State Examination. Mental demands at work were rated by a standardized classification system (O*NET). The association between mental demands and cognitive functioning was analyzed using Generalized Linear Modeling (GENLIN) adjusted for age, gender, self-regulation, working hour status, education, and health-related factors. Results Univariate as well as multivariate analyses demonstrated significant and highly consistent effects of higher mental demands on better performance in cognitive testing. The results also indicated that the effects are independent of education and intelligence. Moreover, analyses of retired individuals implied a significant association between high mental demands at work of the job they once held and a better cognitive functioning in old age. Conclusions In sum, our findings suggest a significant association between high mental demands at work and better cognitive functioning. In this sense, higher levels of mental demands – as brought about by technological changes in the working environment – may also have beneficial effects for the society as they could increase cognitive capacity levels and might even delay cognitive decline in old age. PMID:24914403

Performance-based empathy mediates the influence of working memory on social competence in schizophrenia.

PubMed

Smith, Matthew J; Horan, William P; Cobia, Derin J; Karpouzian, Tatiana M; Fox, Jaclyn M; Reilly, James L; Breiter, Hans C

2014-07-01

Empathic deficits have been linked to poor functioning in schizophrenia, but this work is mostly limited to self-report data. This study examined whether performance-based empathy measures account for incremental variance in social competence and social attainment above and beyond self-reported empathy, neurocognition, and clinical symptoms. Given the importance of working memory in theoretical models of empathy and in the prediction of functioning in schizophrenia, we also examined whether empathy mediates the relationship between working memory and functioning. Sixty outpatients and 45 healthy controls were compared on performance-based measures of 3 key components of empathic responding, including facial affect perception, emotional empathy (affective responsiveness), and cognitive empathy (emotional perspective-taking). Participants also completed measures of self-reported empathy, neurocognition, clinical symptoms, and social competence and attainment. Patients demonstrated lower accuracy than controls across the 3 performance-based empathy measures. Among patients, these measures showed minimal relations to self-reported empathy but significantly correlated with working memory and other neurocognitive functions as well as symptom levels. Furthermore, cognitive empathy explained significant incremental variance in social competence (∆R (2) = .07, P < .05) and was found to mediate the relation between working memory and social competence. Performance-based measures of empathy were sensitive to functionally relevant disturbances in schizophrenia. Working memory deficits appear to have an important effect on these disruptions in empathy. Empathy is emerging as a promising new area for social cognitive research and for novel recovery-oriented treatment development. © The Author 2013. Published by Oxford University Press on behalf of the Maryland Psychiatric Research Center. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Present status and future of the sophisticated work station

NASA Astrophysics Data System (ADS)

Ishida, Haruhisa

The excellency of the work station is explained, by comparing the functions of software and hardware of work station with those of personal computer. As one of the examples utilizing the functions of work station, desk top publishing is explained. By describing the competition between the Group of ATT · Sun Microsystems which intends to have the leadership by integrating Berkeley version which is most popular at this moment and System V version, and the group led by IBM, future of UNIX as OS of work station is predicted. Development of RISC processor, TRON Plan and Sigma Projects by MITI are also mentioned as its background.

Decreased prefrontal functional brain response during memory testing in women with Cushing's syndrome in remission.

PubMed

Ragnarsson, Oskar; Stomby, Andreas; Dahlqvist, Per; Evang, Johan A; Ryberg, Mats; Olsson, Tommy; Bollerslev, Jens; Nyberg, Lars; Johannsson, Gudmundur

2017-08-01

Neurocognitive dysfunction is an important feature of Cushing's syndrome (CS). Our hypothesis was that patients with CS in remission have decreased functional brain responses in the prefrontal cortex and hippocampus during memory testing. In this cross-sectional study we included 19 women previously treated for CS and 19 controls matched for age, gender, and education. The median remission time was 7 (IQR 6-10) years. Brain activity was studied with functional magnetic resonance imaging during episodic- and working-memory tasks. The primary regions of interest were the prefrontal cortex and the hippocampus. A voxel-wise comparison of functional brain responses in patients and controls was performed. During episodic-memory encoding, patients displayed lower functional brain responses in the left and right prefrontal gyrus (p<0.001) and in the right inferior occipital gyrus (p<0.001) compared with controls. There was a trend towards lower functional brain responses in the left posterior hippocampus in patients (p=0.05). During episodic-memory retrieval, the patients displayed lower functional brain responses in several brain areas with the most predominant difference in the right prefrontal cortex (p<0.001). During the working memory task, patients had lower response in the prefrontal cortices bilaterally (p<0.005). Patients, but not controls, had lower functional brain response during a more complex working memory task compared with a simpler one. In conclusion, women with CS in long-term remission have reduced functional brain responses during episodic and working memory testing. This observation extends previous findings showing long-term adverse effects of severe hypercortisolaemia on brain function. Copyright © 2017 Elsevier Ltd. All rights reserved.

Analysis of functional redundancies within the Arabidopsis TCP transcription factor family.

PubMed

Danisman, Selahattin; van Dijk, Aalt D J; Bimbo, Andrea; van der Wal, Froukje; Hennig, Lars; de Folter, Stefan; Angenent, Gerco C; Immink, Richard G H

2013-12-01

Analyses of the functions of TEOSINTE-LIKE1, CYCLOIDEA, and PROLIFERATING CELL FACTOR1 (TCP) transcription factors have been hampered by functional redundancy between its individual members. In general, putative functionally redundant genes are predicted based on sequence similarity and confirmed by genetic analysis. In the TCP family, however, identification is impeded by relatively low overall sequence similarity. In a search for functionally redundant TCP pairs that control Arabidopsis leaf development, this work performed an integrative bioinformatics analysis, combining protein sequence similarities, gene expression data, and results of pair-wise protein-protein interaction studies for the 24 members of the Arabidopsis TCP transcription factor family. For this, the work completed any lacking gene expression and protein-protein interaction data experimentally and then performed a comprehensive prediction of potential functional redundant TCP pairs. Subsequently, redundant functions could be confirmed for selected predicted TCP pairs by genetic and molecular analyses. It is demonstrated that the previously uncharacterized class I TCP19 gene plays a role in the control of leaf senescence in a redundant fashion with TCP20. Altogether, this work shows the power of combining classical genetic and molecular approaches with bioinformatics predictions to unravel functional redundancies in the TCP transcription factor family.

Analysis of functional redundancies within the Arabidopsis TCP transcription factor family

PubMed Central

Danisman, Selahattin; de Folter, Stefan; Immink, Richard G. H.

2013-01-01

Analyses of the functions of TEOSINTE-LIKE1, CYCLOIDEA, and PROLIFERATING CELL FACTOR1 (TCP) transcription factors have been hampered by functional redundancy between its individual members. In general, putative functionally redundant genes are predicted based on sequence similarity and confirmed by genetic analysis. In the TCP family, however, identification is impeded by relatively low overall sequence similarity. In a search for functionally redundant TCP pairs that control Arabidopsis leaf development, this work performed an integrative bioinformatics analysis, combining protein sequence similarities, gene expression data, and results of pair-wise protein–protein interaction studies for the 24 members of the Arabidopsis TCP transcription factor family. For this, the work completed any lacking gene expression and protein–protein interaction data experimentally and then performed a comprehensive prediction of potential functional redundant TCP pairs. Subsequently, redundant functions could be confirmed for selected predicted TCP pairs by genetic and molecular analyses. It is demonstrated that the previously uncharacterized class I TCP19 gene plays a role in the control of leaf senescence in a redundant fashion with TCP20. Altogether, this work shows the power of combining classical genetic and molecular approaches with bioinformatics predictions to unravel functional redundancies in the TCP transcription factor family. PMID:24129704

Applying an Integrative Framework of Executive Function to Preschoolers With Specific Language Impairment.

PubMed

Kapa, Leah L; Plante, Elena; Doubleday, Kevin

2017-08-16

The first goal of this research was to compare verbal and nonverbal executive function abilities between preschoolers with and without specific language impairment (SLI). The second goal was to assess the group differences on 4 executive function components in order to determine if the components may be hierarchically related as suggested within a developmental integrative framework of executive function. This study included 26 4- and 5-year-olds diagnosed with SLI and 26 typically developing age- and sex-matched peers. Participants were tested on verbal and nonverbal measures of sustained selective attention, working memory, inhibition, and shifting. The SLI group performed worse compared with typically developing children on both verbal and nonverbal measures of sustained selective attention and working memory, the verbal inhibition task, and the nonverbal shifting task. Comparisons of standardized group differences between executive function measures revealed a linear increase with the following order: working memory, inhibition, shifting, and sustained selective attention. The pattern of results suggests that preschoolers with SLI have deficits in executive functioning compared with typical peers, and deficits are not limited to verbal tasks. A significant linear relationship between group differences across executive function components supports the possibility of a hierarchical relationship between executive function skills.

Work disabilities and unmet needs for health care and rehabilitation among jobseekers: a community-level investigation using multidimensional work ability assessments

PubMed Central

Kerätär, Raija; Taanila, Anja; Jokelainen, Jari; Soukainen, Jouko; Ala-Mursula, Leena

2016-01-01

Objective Comprehensive understanding of the prevalence and quality of work disabilities and unmet needs for health care and rehabilitation to support return to work (RTW) among jobseekers. Design Community-level, cross-sectional analysis with multidimensional clinical work ability assessments. Setting Paltamo, Finland. Participants Unemployed citizens either participating in the Full-Employment Project or long-term unemployed (n = 230, 81%). Main outcome measures Based on data from theme interviews, patient records, supervisors’ observations of work performance and clinical examinations, a physician concluded the individual’s work ability, categorised into four groups: good work ability, good work ability expected after RTW support, able to transitional work only or unable to work. These groups were cross tabulated with primary diagnoses, types of plans to support RTW, as well as categories of social functioning and motivation, for which sensitivity and specificity scores in detecting work disability were calculated. Results Only about half of the jobseekers had good work ability, 27% were found unable to work in the open labour market and 15% even eligible for a disability pension. For 20%, care or rehabilitation was seen necessary to enable RTW. Poor supervisor- and self-rated performance at work or poor social functioning appeared as sensitive measures in detecting work disability. Conclusions Work disabilities and unmet needs for health care and rehabilitation are highly prevalent among jobseekers, as depicted using a multidimensional work ability assessment procedure inspired by the International Classification of Functioning (ICF). Further development of work ability assessment practices is clearly needed. KEY POINTSAlthough the association of unemployment with poor health is well known, evidence on the work ability of the unemployed remains scarce.Work disabilities are common among the unemployed.Multidimensional work ability assessment among the unemployed reveals unmet needs for care and rehabilitation to support return to work.Context sensitivity may add to the accuracy of the doctor’s conclusions on work ability. PMID:27804309

Work disabilities and unmet needs for health care and rehabilitation among jobseekers: a community-level investigation using multidimensional work ability assessments.

PubMed

Kerätär, Raija; Taanila, Anja; Jokelainen, Jari; Soukainen, Jouko; Ala-Mursula, Leena

2016-12-01

Comprehensive understanding of the prevalence and quality of work disabilities and unmet needs for health care and rehabilitation to support return to work (RTW) among jobseekers. Community-level, cross-sectional analysis with multidimensional clinical work ability assessments. Paltamo, Finland. Unemployed citizens either participating in the Full-Employment Project or long-term unemployed (n = 230, 81%). Based on data from theme interviews, patient records, supervisors' observations of work performance and clinical examinations, a physician concluded the individual's work ability, categorised into four groups: good work ability, good work ability expected after RTW support, able to transitional work only or unable to work. These groups were cross tabulated with primary diagnoses, types of plans to support RTW, as well as categories of social functioning and motivation, for which sensitivity and specificity scores in detecting work disability were calculated. Only about half of the jobseekers had good work ability, 27% were found unable to work in the open labour market and 15% even eligible for a disability pension. For 20%, care or rehabilitation was seen necessary to enable RTW. Poor supervisor- and self-rated performance at work or poor social functioning appeared as sensitive measures in detecting work disability. Work disabilities and unmet needs for health care and rehabilitation are highly prevalent among jobseekers, as depicted using a multidimensional work ability assessment procedure inspired by the International Classification of Functioning (ICF). Further development of work ability assessment practices is clearly needed. KEY POINTS Although the association of unemployment with poor health is well known, evidence on the work ability of the unemployed remains scarce. Work disabilities are common among the unemployed. Multidimensional work ability assessment among the unemployed reveals unmet needs for care and rehabilitation to support return to work. Context sensitivity may add to the accuracy of the doctor's conclusions on work ability.

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

PubMed

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.

Improving the work function of the niobium surface of SRF cavities by plasma processing

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

Tyagi, P. V.; Doleans, M.; Hannah, B.

2016-01-01

An in situ plasma processing technique using chemically reactive oxygen plasma to remove hydrocarbons from superconducting radio frequency cavity surfaces at room temperature was developed at the spallation neutron source, at Oak Ridge National Laboratory. To understand better the interaction between the plasma and niobium surface, surface studies on small samples were performed. In this article, we report the results from those surface studies. The results show that plasma processing removes hydrocarbons from top surface and improves the surface work function by 0.5₋1.0 eV. Improving the work function of RF surface of cavities can help to improve their operational performance.

Device for providing high-intensity ion or electron beam

DOEpatents

McClanahan, Edwin D.; Moss, Ronald W.

1977-01-01

A thin film of a low-thermionic-work-function material is maintained on the cathode of a device for producing a high-current, low-pressure gas discharge by means of sputter deposition from an auxiliary electrode. The auxiliary electrode includes a surface with a low-work-function material, such as thorium, uranium, plutonium or one of the rare earth elements, facing the cathode but at a disposition and electrical potential so as to extract ions from the gas discharge and sputter the low-work-function material onto the cathode. By continuously replenishing the cathode film, high thermionic emissions and ion plasmas can be realized and maintained over extended operating periods.

Soft materials design via self assembly of functionalized icosahedral particles

NASA Astrophysics Data System (ADS)

Muthukumar, Vidyalakshmi Chockalingam

In this work we simulate self assembly of icosahedral building blocks using a coarse grained model of the icosahedral capsid of virus 1m1c. With significant advancements in site-directed functionalization of these macromolecules [1], we propose possible application of such self-assembled materials for drug delivery. While there have been some reports on organization of viral particles in solution through functionalization, exploiting this behaviour for obtaining well-ordered stoichiometric structures has not yet been explored. Our work is in well agreement with the earlier simulation studies of icosahedral gold nanocrystals, giving chain like patterns [5] and also broadly in agreement with the wet lab works of Finn, M.G. et al., who have shown small predominantly chain-like aggregates with mannose-decorated Cowpea Mosaic Virus (CPMV) [22] and small two dimensional aggregates with oligonucleotide functionalization on the CPMV capsid [1]. To quantify the results of our Coarse Grained Molecular Dynamics Simulations I developed analysis routines in MATLAB using which we found the most preferable nearest neighbour distances (from the radial distribution function (RDF) calculations) for different lengths of the functional groups and under different implicit solvent conditions, and the most frequent coordination number for a virus particle (histogram plots further using the information from RDF). Visual inspection suggests that our results most likely span the low temperature limits explored in the works of Finn, M.G. et al., and show a good degree of agreement with the experimental results in [1] at an annealing temperature of 4°C. Our work also reveals the possibility of novel stoichiometric N-mer type aggregates which could be synthesized using these capsids with appropriate functionalization and solvent conditions.

Pursuing the flow of information: connectivity between bilateral premotor cortices predicts better accuracy in the phonological working memory task.

PubMed

Ono, Yumie; Nanjo, Tatsuya; Ishiyama, Atsushi

2013-01-01

Using Magnetoencephalography (MEG) we studied functional connectivity of cortical areas during phonological working memory task. Six subjects participated in the experiment and their neuronal activity was measured by a 306-channel MEG system. We used a modified version of the visual Sternberg paradigm, which required subjects to memorize 8 alphabet letters in 2s for a late recall period. We estimated functional connectivity of oscillatory regional brain activities during the encoding session for each trial of each subject using beamformer source reconstruction and Granger causality analysis. Regional brain activities were mostly found in the bilateral premotor cortex (Brodmann area (BA) 6: PMC), the right dorsolateral prefrontal cortex (BA 9: DLPFC), and the right frontal eye field (BA 8). Considering that the left and right PMCs participate in the functions of phonological loop (PL) and the visuospatial sketchpad (VS) in the Baddeley's model of working memory, respectively, our result suggests that subjects utilized either single function or both functions of working memory circuitry to execute the task. Interestingly, the accuracy of the task was significantly higher in the trials where the alpha band oscillatory activities in the bilateral PMCs established functional connectivity compared to those where the PMC was not working in conjunction with its counterpart. Similar relationship was found in the theta band oscillatory activities between the right PMC and the right DLPFC, however in this case the establishment of functional connectivity significantly decreased the accuracy of the task. These results suggest that sharing the memory load with both PL- and VS- type memory storage circuitries contributed to better performance in the highly-demanding cognitive task.

The impact of night-shift work on platelet function in healthy medical staff.

PubMed

Nakao, Tomoko; Yasumoto, Atsushi; Tokuoka, Suzumi; Kita, Yoshihiro; Kawahara, Takuya; Daimon, Masao; Yatomi, Yutaka

2018-04-18

Rotating shift work has been reported to increase the risk of cardiovascular diseases. Vascular endothelial dysfunction and platelet activation are among the leading causes of thrombus formation in patients with myocardial infarction or stroke. Endothelial function has been shown to be impaired immediately after night-shift work; however, it is not known whether platelets are also activated. The aim of this study was to investigate the acute impact of night-shift work on platelet function. This observational study included 11 healthy medical staff members (seven women, median age 32 years). We examined each subject's platelet aggregation rates and the serum concentrations of eicosanoid mediators after night-shift work and on day-shift work without preceding night-shift work (baseline). Platelet aggregation did not differ from baseline levels after night-shift work. However, serum cyclooxygenase (COX)-metabolized eicosanoid mediators, particularly thromboxane (Tx) B 2 (a stable metabolite of TxA 2 and the most important marker of platelet activation), were significantly higher after the night-shift than at baseline (median 65.3 vs 180.4 ng/ml). Although platelet aggregation did not increase, there was an increase in serum COX-metabolized eicosanoid mediators such as TxB 2 in healthy medical staff after night-shift work. This platelet hypersensitivity may be one of the mechanisms underlying the significant association between night-shift work and adverse cardiovascular outcomes.

Tools of the Mind. What Works Clearinghouse Intervention Report

ERIC Educational Resources Information Center

What Works Clearinghouse, 2008

2008-01-01

"Tools of the Mind" is an early childhood curriculum for preschool and kindergarten children, designed to foster children's executive function through development of self-regulation, working memory, and cognitive flexibility. Activities emphasize both executive functioning and academic skills. One study of "Tools of the Mind"…

Visuo-spatial processing and executive functions in children with specific language impairment

PubMed Central

Marton, Klara

2007-01-01

Background Individual differences in complex working memory tasks reflect simultaneous processing, executive functions, and attention control. Children with specific language impairment (SLI) show a deficit in verbal working memory tasks that involve simultaneous processing of information. Aims The purpose of the study was to examine executive functions and visuo-spatial processing and working memory in children with SLI and in their typically developing peers (TLD). Experiment 1 included 40 children with SLI (age=5;3–6;10) and 40 children with TLD (age=5;3–6;7); Experiment 2 included 25 children with SLI (age=8;2–11;2) and 25 children with TLD (age=8;3–11;0). It was examined whether the difficulties that children with SLI show in verbal working memory tasks are also present in visuo-spatial working memory. Methods & Procedures In Experiment 1, children's performance was measured with three visuo-spatial processing tasks: space visualization, position in space, and design copying. The stimuli in Experiment 2 were two widely used neuropsychological tests: the Wisconsin Card Sorting Test — 64 (WCST-64) and the Tower of London test (TOL). Outcomes & Results In Experiment 1, children with SLI performed more poorly than their age-matched peers in all visuo-spatial working memory tasks. There was a subgroup within the SLI group that included children whose parents and teachers reported a weakness in the child's attention control. These children showed particular difficulties in the tasks of Experiment 1. The results support Engle's attention control theory: individuals need good attention control to perform well in visuo-spatial working memory tasks. In Experiment 2, the children with SLI produced more perseverative errors and more rule violations than their peers. Conclusions Executive functions have a great impact on SLI children's working memory performance, regardless of domain. Tasks that require an increased amount of attention control and executive functions are more difficult for the children with SLI than for their peers. Most children with SLI scored either below average or in the low average range on the neuropsychological tests that measured executive functions. PMID:17852522

Functional networks in parallel with cortical development associate with executive functions in children.

PubMed

Zhong, Jidan; Rifkin-Graboi, Anne; Ta, Anh Tuan; Yap, Kar Lai; Chuang, Kai-Hsiang; Meaney, Michael J; Qiu, Anqi

2014-07-01

Children begin performing similarly to adults on tasks requiring executive functions in late childhood, a transition that is probably due to neuroanatomical fine-tuning processes, including myelination and synaptic pruning. In parallel to such structural changes in neuroanatomical organization, development of functional organization may also be associated with cognitive behaviors in children. We examined 6- to 10-year-old children's cortical thickness, functional organization, and cognitive performance. We used structural magnetic resonance imaging (MRI) to identify areas with cortical thinning, resting-state fMRI to identify functional organization in parallel to cortical development, and working memory/response inhibition tasks to assess executive functioning. We found that neuroanatomical changes in the form of cortical thinning spread over bilateral frontal, parietal, and occipital regions. These regions were engaged in 3 functional networks: sensorimotor and auditory, executive control, and default mode network. Furthermore, we found that working memory and response inhibition only associated with regional functional connectivity, but not topological organization (i.e., local and global efficiency of information transfer) of these functional networks. Interestingly, functional connections associated with "bottom-up" as opposed to "top-down" processing were more clearly related to children's performance on working memory and response inhibition, implying an important role for brain systems involved in late childhood. © The Author 2013. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Understanding the bond-energy, hardness, and adhesive force from the phase diagram via the electron work function

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

Lu, Hao; Huang, Xiaochen; Li, Dongyang, E-mail: dongyang.li@ualberta.ca

2014-11-07

Properties of metallic materials are intrinsically determined by their electron behavior. However, relevant theoretical treatment involving quantum mechanics is complicated and difficult to be applied in materials design. Electron work function (EWF) has been demonstrated to be a simple but fundamental parameter which well correlates properties of materials with their electron behavior and could thus be used to predict material properties from the aspect of electron activities in a relatively easy manner. In this article, we propose a method to extract the electron work functions of binary solid solutions or alloys from their phase diagrams and use this simple approachmore » to predict their mechanical strength and surface properties, such as adhesion. Two alloys, Fe-Ni and Cu-Zn, are used as samples for the study. EWFs extracted from phase diagrams show same trends as experimentally observed ones, based on which hardness and surface adhesive force of the alloys are predicted. This new methodology provides an alternative approach to predict material properties based on the work function, which is extractable from the phase diagram. This work may also help maximize the power of phase diagram for materials design and development.« less

Intact working memory in the absence of forebrain neuronal glycine transporter 1

PubMed Central

Dubroqua, Sylvain; Serrano, Lucas; Boison, Detlev; Feldon, Joram; Gargiulo, Pascual A.; Yee, Benjamin K.

2012-01-01

Glycine transporter 1 (GlyT1) is a potential pharmacological target to ameliorate memory deficits attributable to N-methyl-d-aspartate receptor (NMDAR) hypofunction. Disruption of glycine-reuptake near excitatory synapses is expected to enhance NMDAR function by increasing glycine-B site occupancy. Genetic models with conditional GlyT1 deletion restricted to forebrain neurons have yielded several promising promnesic effects, yet its impact on working memory function remains essentially unanswered because a previous attempt had yielded un-interpretable outcomes. The present study clarified this important outstanding lacuna using a within-subject multi-paradigm approach. Here, a consistent lack of effects was convincingly demonstrated across three working memory test paradigms – the radial arm maze, the cheeseboard maze, and the water maze. These null outcomes contrasted with the phenotype of enhanced working memory performance seen in mutant mice with GlyT1 deletion extended to cortical/hippocampal glial cells. It follows that glial-based GlyT1 might be more closely linked to the modulation of working memory function, and raises the possibility that neuronal and glial GlyT1 may regulate cognitive functions via dissociable mechanisms. PMID:22342492

Working memory network plasticity after anterior temporal lobe resection: a longitudinal functional magnetic resonance imaging study

PubMed Central

Stretton, Jason; Sidhu, Meneka K.; Winston, Gavin P.; Bartlett, Philippa; McEvoy, Andrew W.; Symms, Mark R.; Koepp, Matthias J.; Thompson, Pamela J.

2014-01-01

Working memory is a crucial cognitive function that is disrupted in temporal lobe epilepsy. It is unclear whether this impairment is a consequence of temporal lobe involvement in working memory processes or due to seizure spread to extratemporal eloquent cortex. Anterior temporal lobe resection controls seizures in 50–80% of patients with drug-resistant temporal lobe epilepsy and the effect of surgery on working memory are poorly understood both at a behavioural and neural level. We investigated the impact of temporal lobe resection on the efficiency and functional anatomy of working memory networks. We studied 33 patients with unilateral medial temporal lobe epilepsy (16 left) before, 3 and 12 months after anterior temporal lobe resection. Fifteen healthy control subjects were also assessed in parallel. All subjects had neuropsychological testing and performed a visuospatial working memory functional magnetic resonance imaging paradigm on these three separate occasions. Changes in activation and deactivation patterns were modelled individually and compared between groups. Changes in task performance were included as regressors of interest to assess the efficiency of changes in the networks. Left and right temporal lobe epilepsy patients were impaired on preoperative measures of working memory compared to controls. Working memory performance did not decline following left or right temporal lobe resection, but improved at 3 and 12 months following left and, to a lesser extent, following right anterior temporal lobe resection. After left anterior temporal lobe resection, improved performance correlated with greater deactivation of the left hippocampal remnant and the contralateral right hippocampus. There was a failure of increased deactivation of the left hippocampal remnant at 3 months after left temporal lobe resection compared to control subjects, which had normalized 12 months after surgery. Following right anterior temporal lobe resection there was a progressive increase of activation in the right superior parietal lobe at 3 and 12 months after surgery. There was greater deactivation of the right hippocampal remnant compared to controls between 3 and 12 months after right anterior temporal lobe resection that was associated with lesser improvement in task performance. Working memory improved after anterior temporal lobe resection, particularly following left-sided resections. Postoperative working memory was reliant on the functional capacity of the hippocampal remnant and, following left resections, the functional reserve of the right hippocampus. These data suggest that working memory following temporal lobe resection is dependent on the engagement of the posterior medial temporal lobes and eloquent cortex. PMID:24691395

Functional Requirements for an Electronic Work Package System

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

Oxstrand, Johanna H.

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 basicmore » 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.« less

Testing a path-analytic mediation model of how motivational enhancement physiotherapy improves physical functioning in pain patients.

PubMed

Cheing, Gladys; Vong, Sinfia; Chan, Fong; Ditchman, Nicole; Brooks, Jessica; Chan, Chetwyn

2014-12-01

Pain is a complex phenomenon not easily discerned from psychological, social, and environmental characteristics and is an oft cited barrier to return to work for people experiencing low back pain (LBP). The purpose of this study was to evaluate a path-analytic mediation model to examine how motivational enhancement physiotherapy, which incorporates tenets of motivational interviewing, improves physical functioning of patients with chronic LBP. Seventy-six patients with chronic LBP were recruited from the outpatient physiotherapy department of a government hospital in Hong Kong. The re-specified path-analytic model fit the data very well, χ (2)(3, N = 76) = 3.86, p = .57; comparative fit index = 1.00; and the root mean square error of approximation = 0.00. Specifically, results indicated that (a) using motivational interviewing techniques in physiotherapy was associated with increased working alliance with patients, (b) working alliance increased patients' outcome expectancy and (c) greater outcome expectancy resulted in a reduction of subjective pain intensity and improvement in physical functioning. Change in pain intensity also directly influenced improvement in physical functioning. The effect of motivational enhancement therapy on physical functioning can be explained by social-cognitive factors such as motivation, outcome expectancy, and working alliance. The use of motivational interviewing techniques to increase outcome expectancy of patients and improve working alliance could further strengthen the impact of physiotherapy on rehabilitation outcomes of patients with chronic LBP.

Comparative investigation of novel hetero gate dielectric and drain engineered charge plasma TFET for improved DC and RF performance

NASA Astrophysics Data System (ADS)

Yadav, Dharmendra Singh; Verma, Abhishek; Sharma, Dheeraj; Tirkey, Sukeshni; Raad, Bhagwan Ram

2017-11-01

Tunnel-field-effect-transistor (TFET) has emerged as one of the most prominent devices to replace conventional MOSFET due to its ability to provide sub-threshold slope below 60 mV/decade (SS ≤ 60 mV/decade) and low leakage current. Despite this, TFETs suffer from ambipolar behavior, lower ON-state current, and poor RF performance. To address these issues, we have introduced drain and gate work function engineering with hetero gate dielectric for the first time in charge plasma based doping-less TFET (DL TFET). In this, the usage of dual work functionality over the drain region significantly reduces the ambipolar behavior of the device by varying the energy barrier at drain/channel interface. Whereas, the presence of dual work function at the gate terminal increases the ON-state current (ION). The combined effect of dual work function at the gate and drain electrode results in the increment of ON-state current (ION) and decrement of ambipolar conduction (Iambi) respectively. Furthermore, the incorporation of hetero gate dielectric along with dual work functionality at the drain and gate electrode provides an overall improvement in the performance of the device in terms of reduction in ambipolarity, threshold voltage and sub-threshold slope along with improved ON-state current and high frequency figures of merit.

F4TCNQ on Cu, Ag, and Au as prototypical example for a strong organic acceptor on coinage metals

NASA Astrophysics Data System (ADS)

Rangger, Gerold M.; Hofmann, Oliver T.; Romaner, Lorenz; Heimel, Georg; Bröker, Benjamin; Blum, Ralf-Peter; Johnson, Robert L.; Koch, Norbert; Zojer, Egbert

2009-04-01

Metal work-function modification with the help of organic acceptors is an efficient tool to significantly enhance the performance of modern state-of-the-art organic molecular electronic devices. Here, the prototypical organic acceptor 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane, F4TCNQ, is characterized on Ag(111), Au(111), and Cu(111) metal surfaces by means of density-functional theory calculations. Particular attention is paid to charge-transfer processes at the metal-organic interface; a subtle balance between charge forward and backward donations in combination with a strong adsorption-induced geometry change are found to be responsible for the observed increase in the system work function. A larger effect is obtained for the metals with larger initial work function. Interestingly, this results in similar charge-injection barriers from the substrate metal into an organic semiconductor deposited on top of the F4TCNQ layer. The impact of the F4TCNQ packing density of the electronic properties of the interface is also addressed. Comparing the calculated energy-level alignments and work-function modifications to experimental data from ultraviolet photoelectron spectroscopy yields good agreement between experiments and simulations.

Work Function of Oxide Ultrathin Films on the Ag(100) Surface.

PubMed

Sementa, Luca; Barcaro, Giovanni; Negreiros, Fabio R; Thomas, Iorwerth O; Netzer, Falko P; Ferrari, Anna Maria; Fortunelli, Alessandro

2012-02-14

Theoretical calculations of the work function of monolayer (ML) and bilayer (BL) oxide films on the Ag(100) surface are reported and analyzed as a function of the nature of the oxide for first-row transition metals. The contributions due to charge compression, charge transfer and rumpling are singled out. It is found that the presence of empty d-orbitals in the oxide metal can entail a charge flow from the Ag(100) surface to the oxide film which counteracts the decrease in the work function due to charge compression. This flow can also depend on the thickness of the film and be reduced in passing from ML to BL systems. A regular trend is observed along first-row transition metals, exhibiting a maximum for CuO, in which the charge flow to the oxide is so strong as to reverse the direction of rumpling. A simple protocol to estimate separately the contribution due to charge compression is discussed, and the difference between the work function of the bare metal surface and a Pauling-like electronegativity of the free oxide slabs is used as a descriptor quantity to predict the direction of charge transfer.

Influence of organic and functional dyspepsia on work productivity: the HEROES-DIP study.

PubMed

Sander, Guilherme Becker; Mazzoleni, Luiz Edmundo; Francesconi, Carlos Ferrnando de Magalhães; Balbinotto, Giácomo; Mazzoleni, Felipe; Wortmann, Andre Castagna; Cardoso, Israel de Quadros; Klamt, Alexandre Luis; Milbradt, Tobias Cancian

2011-01-01

Dyspepsia is defined as persistent or recurrent abdominal pain or discomfort centered in the upper abdomen. Dyspepsia represents up to 8.3% of all primary care physician visits and causes huge economic costs to patients and to the economy as a whole. The aim of this study was to measure the influence of dyspepsia on work productivity of people within the Brazilian workforce. Adult patients were enrolled if they met the Roma III criteria for uninvestigated dyspepsia. All patients answered a demographic questionnaire. Productivity impairment was measured by the Work Productivity and Activity Impairment questionnaire. Subjects underwent upper gastrointestinal endoscopy and were classified as having functional or organic dyspepsia. The study protocol was approved by the Ethics Committee of Hospital de Clínicas de Porto Alegre, Brazil. Eight hundred fifty patients with dyspepsia were evaluated: 628 were women (73.9%); mean age was 46.4 ± 12.9 years; 387 (45.5%) were active workers. Among active workers, 32.2% mentioned that dyspepsia had caused absenteeism from work during the preceding week and 78% reported a reduction of the work productivity (presenteeism). The lost work productivity score was 35.7% among all employed patients. The affect on work productivity was similar between patients with functional or organic dyspepsia. Our study showed an important influence of dyspepsia on work productivity. We did not find any statistically significant difference on the influence on work between patients with organic dyspepsia and functional dyspepsia. The social impact of these findings is underscored by taking into account the prevalence (up to 40%) of this condition in Brazil. Copyright © 2011 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.

Differential effects of enriched environment at work on cognitive decline in old age.

PubMed

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.

Bright-light effects on cognitive performance in elderly persons working simulated night shifts: psychological well-being as a mediator?

PubMed

Kretschmer, Veronika; Schmidt, Klaus-Helmut; Griefahn, Barbara

2013-11-01

The present study examined whether the relationship between light exposure and cognitive functioning is mediated by psychological well-being in elderly persons working night shifts. The role of psychological well-being has been neglected so far in the relationship between bright light and cognitive performance. Sleepiness and mood were applied as indicators of psychological well-being. Cognitive functioning was examined in terms of concentration, working memory, and divided attention. A total of thirty-two test persons worked in three consecutive simulated night shifts, 16 under bright light (3,000 lux) and 16 under room light (300 lux). Concentration, working memory, and divided attention were measured by computerised tasks. The hypothesised mediators were recorded by questionnaires. Mediation analyses were conducted for estimating direct, total, and indirect effects in simple mediation models. Results indicate that sleepiness and mood did not function as mediators in the prediction of concentration, working memory, and/or divided attention by light exposure. Sleepiness led to an underestimation of the positive bright-light effect on concentration performance. Mood showed only a random effect due to the positive bright-light effect on working memory. Sleepiness and mood could completely be excluded as mediators in the relationship between light exposure and cognitive functioning. This study underlines that psychological well-being of elderly persons is not a critical component in the treatment of bright light on cognitive performance in the night shift workplace. In summary, it becomes evident that bright light has a strong direct and independent effect on cognitive performance, particularly on working memory and concentration.

Employee subjective well-being and physiological functioning: An integrative model.

PubMed

Kuykendall, Lauren; Tay, Louis

2015-01-01

Research shows that worker subjective well-being influences physiological functioning-an early signal of poor health outcomes. While several theoretical perspectives provide insights on this relationship, the literature lacks an integrative framework explaining the relationship. We develop a conceptual model explaining the link between subjective well-being and physiological functioning in the context of work. Integrating positive psychology and occupational stress perspectives, our model explains the relationship between subjective well-being and physiological functioning as a result of the direct influence of subjective well-being on physiological functioning and of their common relationships with work stress and personal resources, both of which are influenced by job conditions.

Working memory performance inversely predicts spontaneous delta and theta-band scaling relations.

PubMed

Euler, Matthew J; Wiltshire, Travis J; Niermeyer, Madison A; Butner, Jonathan E

2016-04-15

Electrophysiological studies have strongly implicated theta-band activity in human working memory processes. Concurrently, work on spontaneous, non-task-related oscillations has revealed the presence of long-range temporal correlations (LRTCs) within sub-bands of the ongoing EEG, and has begun to demonstrate their functional significance. However, few studies have yet assessed the relation of LRTCs (also called scaling relations) to individual differences in cognitive abilities. The present study addressed the intersection of these two literatures by investigating the relation of narrow-band EEG scaling relations to individual differences in working memory ability, with a particular focus on the theta band. Fifty-four healthy adults completed standardized assessments of working memory and separate recordings of their spontaneous, non-task-related EEG. Scaling relations were quantified in each of the five classical EEG frequency bands via the estimation of the Hurst exponent obtained from detrended fluctuation analysis. A multilevel modeling framework was used to characterize the relation of working memory performance to scaling relations as a function of general scalp location in Cartesian space. Overall, results indicated an inverse relationship between both delta and theta scaling relations and working memory ability, which was most prominent at posterior sensors, and was independent of either spatial or individual variability in band-specific power. These findings add to the growing literature demonstrating the relevance of neural LRTCs for understanding brain functioning, and support a construct- and state-dependent view of their functional implications. Copyright © 2016 Elsevier B.V. All rights reserved.

Fluoxetine improves functional work capacity in women with premenstrual dysphoric disorder.

PubMed

Steiner, M; Brown, E; Trzepacz, P; Dillon, J; Berger, C; Carter, D; Reid, R; Stewart, D

2003-02-01

Interference with social and occupational functioning is a key criterion for premenstrual dysphoric disorder (PMDD) and distinguishes it from the less severe premenstrual syndrome (PMS). We conducted a post hoc analysis of the results of a previously reported study evaluating the efficacy of fluoxetine in the management of PMDD, to determine the extent to which women with PMDD perceived impairment in their functional work capacity during the luteal phase of their menstrual cycle. The effects of two doses of fluoxetine vs placebo in alleviating PMDD symptoms and restoring normal work capacity during this period were assessed. We measured baseline follicular vs luteal phase presence of 8 patient-rated functional work capacity-related symptoms on the Premenstrual Tension Scale-Self Rated in 320 women who met diagnostic criteria for late luteal phase dysphoric disorder, now known as PMDD. Women were then randomized to double-blind treatment with either fluoxetine 20 mg/d, fluoxetine 60 mg/d, or placebo daily for 6 menstrual cycles. All 8 work capacity-related symptoms were more likely to be present in the baseline luteal phase than in the baseline follicular phase. A statistically significant improvement from baseline to the average treatment score for the work capacity subscale was detected for both fluoxetine groups compared to the placebo group. This beneficial response to fluoxetine was evident by the first cycle of treatment. Our results demonstrate that fluoxetine at a relatively low dose of 20 mg/d quickly reduced symptoms that negatively affect work capacity and was well tolerated.

Long-term effects of frequent cannabis use on working memory and attention: an fMRI study.

PubMed

Jager, Gerry; Kahn, Rene S; Van Den Brink, Wim; Van Ree, Jan M; Ramsey, Nick F

2006-04-01

Excessive use of cannabis may have long-term effects on cognitive abilities. Mild impairments have been found in several cognitive domains, particularly in memory and attention. It is not clear, however, whether these effects also occur with moderate, recreational use of cannabis. Furthermore, little is known about underlying brain correlates. The aim of this study is to assess brain function in frequent but relatively moderate cannabis users in the domains of working memory and selective attention. Functional magnetic resonance imaging was used to examine verbal working memory and visuo-auditory selective attention in ten frequent cannabis users (after 1 week of abstinence) and ten non-using healthy controls. Groups were similar in age, gender and estimated IQ. Cannabis users and controls performed equally well during the working memory task and the selective attention task. Furthermore, cannabis users did not differ from controls in terms of overall patterns of brain activity in the regions involved in these cognitive functions. However, for working memory, a more specific region-of-interest analysis showed that, in comparison to the controls, cannabis users displayed a significant alteration in brain activity in the left superior parietal cortex. No evidence was found for long-term deficits in working memory and selective attention in frequent cannabis users after 1 week of abstinence. Nonetheless, frequent cannabis use may affect brain function, as indicated by altered neurophysiological dynamics in the left superior parietal cortex during working memory processing.

Task positive and default mode networks during a working memory in children with primary monosymptomatic nocturnal enuresis and healthy controls.

PubMed

Zhang, Kaihua; Ma, Jun; Lei, Du; Wang, Mengxing; Zhang, Jilei; Du, Xiaoxia

2015-10-01

Nocturnal enuresis is a common developmental disorder in children, and primary monosymptomatic nocturnal enuresis (PMNE) is the dominant subtype. This study investigated brain functional abnormalities that are specifically related to working memory in children with PMNE using function magnetic resonance imaging (fMRI) in combination with an n-back task. Twenty children with PMNE and 20 healthy children, group-matched for age and sex, participated in this experiment. Several brain regions exhibited reduced activation during the n-back task in children with PMNE, including the right precentral gyrus and the right inferior parietal lobule extending to the postcentral gyrus. Children with PMNE exhibited decreased cerebral activation in the task-positive network, increased task-related cerebral deactivation during a working memory task, and longer response times. Patients exhibited different brain response patterns to different levels of working memory and tended to compensate by greater default mode network deactivation to sustain normal working memory function. Our results suggest that children with PMNE have potential working memory dysfunction.

Functional Pathways of Social Support for Mental Health in Work and Family Domains Among Chinese Scientific and Technological Professionals.

PubMed

Gan, Yiqun; Gan, Tingting; Chen, Zhiyan; Miao, Miao; Zhang, Kan

2015-10-01

This study investigated the role of social support in the complex pattern of associations among stressors, work-family interferences and depression in the domains of work and family. A questionnaire was administered to a nationwide sample of 11,419 Chinese science and technology professionals. Several structural equation models were specified to determine whether social support functioned as a predictor or a mediator. Using Mplus 5.0, we compared the moderation model, the independence model, the antecedent model and the mediation model. The results revealed that the relationship between work-family interference and social support was domain specific. The independence model fit the data best in the work domain. Both the moderation model and the antecedent model fit the family domain data equally well. The current study was conducted to answer the need for comprehensive investigations of cultural uniqueness in the antecedents of work-family interference. The domain specificity, i.e. the multiple channels of the functions of support in the family domain and not in the work domain, ensures that this study is unique and culturally specific. Copyright © 2014 John Wiley & Sons, Ltd.

Applying a Mixed Methods Framework to Differential Item Function Analyses

ERIC Educational Resources Information Center

Hitchcock, John H.; Johanson, George A.

2015-01-01

Understanding the reason(s) for Differential Item Functioning (DIF) in the context of measurement is difficult. Although identifying potential DIF items is typically a statistical endeavor, understanding the reasons for DIF (and item repair or replacement) might require investigations that can be informed by qualitative work. Such work is…

Visuo-Spatial Processing and Executive Functions in Children with Specific Language Impairment

ERIC Educational Resources Information Center

Marton, Klara

2008-01-01

Background: Individual differences in complex working memory tasks reflect simultaneous processing, executive functions, and attention control. Children with specific language impairment (SLI) show a deficit in verbal working memory tasks that involve simultaneous processing of information. Aims: The purpose of the study was to examine executive…

Functional Brain Network Abnormalities during Verbal Working Memory Performance in Adolescents and Young Adults with Dyslexia

ERIC Educational Resources Information Center

Wolf, Robert Christian; Sambataro, Fabio; Lohr, Christina; Steinbrink, Claudia; Martin, Claudia; Vasic, Nenad

2010-01-01

Behavioral and functional neuroimaging studies indicate deficits in verbal working memory (WM) and frontoparietal dysfunction in individuals with dyslexia. Additionally, structural brain abnormalities in dyslexics suggest a dysconnectivity of brain regions associated with phonological processing. However, little is known about the functional…

Phonological Storage and Executive Function Deficits in Children with Mathematics Difficulties

ERIC Educational Resources Information Center

Peng, Peng; Congying, Sun; Beilei, Li; Sha, Tao

2012-01-01

Children with mathematics difficulties suffer from working memory deficits. This study investigated the deficit profile of phonological storage and executive functions in working memory among children with mathematics difficulties. Based on multiple instruments and two assessment points, 68 children were screened out of 805 fifth graders. Of these…

Working In-Vivo with Client Sense of Unlovability

ERIC Educational Resources Information Center

Tsai, Mavis; Reed, Richard

2012-01-01

Clients sometimes react negatively when their in-session problem behavior is simply blocked. This article illustrates how a FAP (Functional Analytic Psychotherapy) therapist can work effectively in session with a client's problem feeling of unlovability by: 1) understanding its antecedents and functions, 2) using therapeutic love to reinforce…

Construct validity of functional capacity tests in healthy workers

PubMed Central

2013-01-01

Background Functional Capacity (FC) is a multidimensional construct within the activity domain of the International Classification of Functioning, Disability and Health framework (ICF). Functional capacity evaluations (FCEs) are assessments of work-related FC. The extent to which these work-related FC tests are associated to bio-, psycho-, or social factors is unknown. The aims of this study were to test relationships between FC tests and other ICF factors in a sample of healthy workers, and to determine the amount of statistical variance in FC tests that can be explained by these factors. Methods A cross sectional study. The sample was comprised of 403 healthy workers who completed material handling FC tests (lifting low, overhead lifting, and carrying) and static work FC tests (overhead working and standing forward bend). The explainable variables were; six muscle strength tests; aerobic capacity test; and questionnaires regarding personal factors (age, gender, body height, body weight, and education), psychological factors (mental health, vitality, and general health perceptions), and social factors (perception of work, physical workloads, sport-, leisure time-, and work-index). A priori construct validity hypotheses were formulated and analyzed by means of correlation coefficients and regression analyses. Results Moderate correlations were detected between material handling FC tests and muscle strength, gender, body weight, and body height. As for static work FC tests; overhead working correlated fair with aerobic capacity and handgrip strength, and low with the sport-index and perception of work. For standing forward bend FC test, all hypotheses were rejected. The regression model revealed that 61% to 62% of material handling FC tests were explained by physical factors. Five to 15% of static work FC tests were explained by physical and social factors. Conclusions The current study revealed that, in a sample of healthy workers, material handling FC tests were related to physical factors but not to the psychosocial factors measured in this study. The construct of static work FC tests remained largely unexplained. PMID:23758870

A Brain System for Auditory Working Memory.

PubMed

Kumar, Sukhbinder; Joseph, Sabine; Gander, Phillip E; Barascud, Nicolas; Halpern, Andrea R; Griffiths, Timothy D

2016-04-20

The brain basis for auditory working memory, the process of actively maintaining sounds in memory over short periods of time, is controversial. Using functional magnetic resonance imaging in human participants, we demonstrate that the maintenance of single tones in memory is associated with activation in auditory cortex. In addition, sustained activation was observed in hippocampus and inferior frontal gyrus. Multivoxel pattern analysis showed that patterns of activity in auditory cortex and left inferior frontal gyrus distinguished the tone that was maintained in memory. Functional connectivity during maintenance was demonstrated between auditory cortex and both the hippocampus and inferior frontal cortex. The data support a system for auditory working memory based on the maintenance of sound-specific representations in auditory cortex by projections from higher-order areas, including the hippocampus and frontal cortex. In this work, we demonstrate a system for maintaining sound in working memory based on activity in auditory cortex, hippocampus, and frontal cortex, and functional connectivity among them. Specifically, our work makes three advances from the previous work. First, we robustly demonstrate hippocampal involvement in all phases of auditory working memory (encoding, maintenance, and retrieval): the role of hippocampus in working memory is controversial. Second, using a pattern classification technique, we show that activity in the auditory cortex and inferior frontal gyrus is specific to the maintained tones in working memory. Third, we show long-range connectivity of auditory cortex to hippocampus and frontal cortex, which may be responsible for keeping such representations active during working memory maintenance. Copyright © 2016 Kumar et al.

Can psychosocial work conditions protect against age-related cognitive decline? Results from a systematic review

PubMed Central

Nexø, Mette Andersen; Meng, Annette; Borg, Vilhelm

2016-01-01

According to the use it or lose it hypothesis, intellectually stimulating activities postpone age-related cognitive decline. A previous systematic review concluded that a high level of mental work demands and job control protected against cognitive decline. However, it did not distinguish between outcomes that were measured as cognitive function at one point in time or as cognitive decline. Our study aimed to systematically review which psychosocial working conditions were prospectively associated with high levels of cognitive function and/or changes in cognitive function over time. Articles were identified by a systematic literature search (MEDLINE, Web of Science (WOS), PsycNET, Occupational Safety and Health (OSH)). We included only studies with longitudinal designs examining the impact of psychosocial work conditions on outcomes defined as cognitive function or changes in cognitive function. Two independent reviewers compared title-abstract screenings, full-text screenings and quality assessment ratings. Eleven studies were included in the final synthesis and showed that high levels of mental work demands, occupational complexity or job control at one point in time were prospectively associated with higher levels of cognitive function in midlife or late life. However, the evidence to clarify whether these psychosocial factors also affected cognitive decline was insufficient, conflicting or weak. It remains speculative whether job control, job demands or occupational complexity can protect against cognitive decline. Future studies using methodological advancements can reveal whether workers gain more cognitive reserve in midlife and late life than the available evidence currently suggests. The public health implications of a previous review should thereby be redefined accordingly. PMID:27178844

The effect of different types of employment on quality of life.

PubMed

Kober, R; Eggleton, I R C

2005-10-01

Despite research that has investigated whether the financial benefits of open employment exceed the costs, there has been scant research as to the effect sheltered and open employment have upon the quality of life of participants. The importance of this research is threefold: it investigates outcomes explicitly in terms of quality of life; the sample size is comparatively large; and it uses an established and validated questionnaire. One hundred and seventeen people with intellectual disability (ID) who were employed in either open or sheltered employment by disability employment agencies were interviewed. Quality of life was assessed using the Quality of Life Questionnaire. After making an initial assessment to see whether the outcomes achieved depended on type of employment, quality of life scores were analyzed controlling for participants' level of functional work ability (assessed via the Functional Assessment Inventory). The results showed that participants placed in open employment reported statistically significant higher quality of life scores. When the sample was split based upon participants' functional work ability, the type of employment had no effect on the reported quality of life for participants with a low functional work ability. However, for those participants with a high functional work ability, those in open employment reported statistically significantly higher quality of life. The results of this study support the placement of people with ID with high functional work ability into open employment. However, a degree of caution needs to be taken in interpreting the results presented given the disparity in income levels between the two types of employment.

Disorganization and real-world functioning in schizophrenia: Results from the multicenter study of the Italian Network for Research on Psychoses.

PubMed

Rocca, P; Galderisi, S; Rossi, A; Bertolino, A; Rucci, P; Gibertoni, D; Montemagni, C; Bellino, S; Aguglia, E; Amore, M; Bellomo, A; Biondi, M; Carpiniello, B; Cuomo, A; D'Ambrosio, E; dell'Osso, L; Girardi, P; Marchesi, C; Monteleone, P; Montemitro, C; Oldani, L; Pacitti, F; Roncone, R; Siracusano, A; Tenconi, E; Vita, A; Zeppegno, P; Steardo, L; Vignapiano, A; Maj, M

2018-06-10

A general consensus has not yet been reached regarding the role of disorganization symptoms in real-world functioning in schizophrenia. We used structural equations modeling (SEM) to analyze the direct and indirect associations between disorganization and real-world functioning assessed through the Specific Levels of Functioning Scale (SLOF) in 880 subjects with schizophrenia. We found that: 1) conceptual disorganization was directly and strongly connected with SLOF daily activities; difficulty in abstract thinking was associated with moderate strength to all SLOF domains, and poor attention was connected with SLOF work skills; 2) grandiosity was only related with poor work skills, and delusions were associated with poor functioning in all SLOF domains; interpersonal relationships were weakly indirectly influenced by hallucinatory behavior, delusions and unusual thought contents through the mediation of social cognition (SC); 3) among the negative symptoms, avolition had only direct links with SLOF work skills and SLOF activities; anhedonia had direct links with SLOF work skills and SLOF interpersonal and indirect link with SLOF work skills through functional capacity (FC); asociality with SLOF interpersonal; blunted affect had direct links with SLOF activities and indirect links with SLOF interpersonal relationships mediated by SC. Lastly, alogia had only indirect links mediated by SC, FC, and neurocognition (NC). Overall conceptual disorganization is the symptom that contributed more (both directly and indirectly) to the activities of community living in real-world. Thus, it should be considered as a treatment target in intervention programs for patients with schizophrenia. Copyright © 2018. Published by Elsevier B.V.

Errors on interrupter tasks presented during spatial and verbal working memory performance are linearly linked to large-scale functional network connectivity in high temporal resolution resting state fMRI.

PubMed

Magnuson, Matthew Evan; Thompson, Garth John; Schwarb, Hillary; Pan, Wen-Ju; McKinley, Andy; Schumacher, Eric H; Keilholz, Shella Dawn

2015-12-01

The brain is organized into networks composed of spatially separated anatomical regions exhibiting coherent functional activity over time. Two of these networks (the default mode network, DMN, and the task positive network, TPN) have been implicated in the performance of a number of cognitive tasks. To directly examine the stable relationship between network connectivity and behavioral performance, high temporal resolution functional magnetic resonance imaging (fMRI) data were collected during the resting state, and behavioral data were collected from 15 subjects on different days, exploring verbal working memory, spatial working memory, and fluid intelligence. Sustained attention performance was also evaluated in a task interleaved between resting state scans. Functional connectivity within and between the DMN and TPN was related to performance on these tasks. Decreased TPN resting state connectivity was found to significantly correlate with fewer errors on an interrupter task presented during a spatial working memory paradigm and decreased DMN/TPN anti-correlation was significantly correlated with fewer errors on an interrupter task presented during a verbal working memory paradigm. A trend for increased DMN resting state connectivity to correlate to measures of fluid intelligence was also observed. These results provide additional evidence of the relationship between resting state networks and behavioral performance, and show that such results can be observed with high temporal resolution fMRI. Because cognitive scores and functional connectivity were collected on nonconsecutive days, these results highlight the stability of functional connectivity/cognitive performance coupling.

Hepatic (Liver) Function Panel

MedlinePlus

... Educators Search English Español Blood Test: Hepatic (Liver) Function Panel KidsHealth / For Parents / Blood Test: Hepatic (Liver) ... kidneys ) is working. What Is a Hepatic (Liver) Function Panel? A liver function panel is a blood ...

Working memory, math performance, and math anxiety.

PubMed

Ashcraft, Mark H; Krause, Jeremy A

2007-04-01

The cognitive literature now shows how critically math performance depends on working memory, for any form of arithmetic and math that involves processes beyond simple memory retrieval. The psychometric literature is also very clear on the global consequences of mathematics anxiety. People who are highly math anxious avoid math: They avoid elective coursework in math, both in high school and college, they avoid college majors that emphasize math, and they avoid career paths that involve math. We go beyond these psychometric relationships to examine the cognitive consequences of math anxiety. We show how performance on a standardized math achievement test varies as a function of math anxiety, and that math anxiety compromises the functioning of working memory. High math anxiety works much like a dual task setting: Preoccupation with one's math fears and anxieties functions like a resource-demanding secondary task. We comment on developmental and educational factors related to math and working memory, and on factors that may contribute to the development of math anxiety.

Extraction of physical Schottky parameters using the Lambert function in Ni/AlGaN/GaN HEMT devices with defined conduction phenomena

NASA Astrophysics Data System (ADS)

Latry, O.; Divay, A.; Fadil, D.; Dherbécourt, P.

2017-01-01

Electrical characterization analyses are proposed in this work using the Lambert function on Schottky junctions in GaN wide band gap semiconductor devices for extraction of physical parameters. The Lambert function is used to give an explicit expression of the current in the Schottky junction. This function is applied with defined conduction phenomena, whereas other work presented arbitrary (or undefined) conduction mechanisms in such parameters’ extractions. Based upon AlGaN/GaN HEMT structures, extractions of parameters are undergone in order to provide physical characteristics. This work highlights a new expression of current with defined conduction phenomena in order to quantify the physical properties of Schottky contacts in AlGaN/GaN HEMT transistors. Project supported by the French Department of Defense (DGA).

Observation of quantum oscillation of work function in ultrathin-metal/semiconductor junctions

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

Takhar, Kuldeep; Meer, Mudassar; Khachariya, Dolar

2015-09-15

Quantization in energy level due to confinement is generally observed for semiconductors. This property is used for various quantum devices, and it helps to improve the characteristics of conventional devices. Here, the authors have demonstrated the quantum size effects in ultrathin metal (Ni) layers sandwiched between two large band-gap materials. The metal work function is found to oscillate as a function of its thickness. The thermionic emission current bears the signature of the oscillating work function, which has a linear relationship with barrier heights. This methodology allows direct observation of quantum oscillations in metals at room temperature using a Schottkymore » diode and electrical measurements using source-measure-units. The observed phenomena can provide additional mechanism to tune the barrier height of metal/semiconductor junctions, which are used for various electronic devices.« less

Self-consistent many-electron theory of electron work functions and surface potential characteristics for selected metals

NASA Technical Reports Server (NTRS)

Smith, J. R.

1969-01-01

Electron work functions, surface potentials, and electron number density distributions and electric fields in the surface region of 26 metals were calculated from first principles within the free electron model. Calculation proceeded from an expression of the total energy as a functional of the electron number density, including exchange and correlation energies, as well as a first inhomogeneity term. The self-consistent solution was obtained via a variational procedure. Surface barriers were due principally to many-body effects; dipole barriers were small only for some alkali metals, becoming quite large for the transition metals. Surface energies were inadequately described by this model, which neglects atomistic effects. Reasonable results were obtained for electron work functions and surface potential characteristics, maximum electron densities varying by a factor of over 60.

Interest of the Ergo-Kit(®) for the clinical practice of the occupational physician. A study of 149 patients recruited in a rehabilitation program.

PubMed

Caron, J; Ronzi, Y; Bodin, J; Richard, I; Bontoux, L; Roquelaure, Y; Petit, A

2015-10-01

Functional capacity evaluation is commonly used to assess the abilities of patients to perform some tasks. Ergo-Kit(®) is a validated tool assessing both functional capacities of patients and workplace demands. The objective of this study was to evaluate the relevance of the Ergo-Kit(®) data for occupational physicians during the return-to-work process. A retrospective and monocenter study was conducted on all patients included in a rehabilitation program and assessed with the Ergo-Kit(®) tool between 2005 and 2014. Workplace demands and patients' functional capacities were evaluated and confronted. Self-beliefs and perceived disability were also assessed and compared to the functional capacity evaluation. One hundred and forty-nine working-age patients (85 men, 64 women; 39±12 years) suffering from musculoskeletal disorders or other diseases were included. Main causes of mismatch between workplace demands and functional capacities were manual handling of loads, postures with arms away from the body and repetitive motions at work; sitting posture was correlated with a lesser physical workload; and Oswestry score was correlated with functional capacities evaluated by the Ergo-Kit(®). Ergo-Kit(®) is a relevant tool to assess the multidimensional aspects of workplace demands and functional capacities. It could be very helpful for occupational physicians to manage return-to-work. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

[Influence of factors on independence of patients after stroke in early rehabilitation stage].

PubMed

Petruseviciene, Daiva; Krisciūnas, Aleksandras

2005-01-01

Brain stroke is the main cause of disability starting from age of 40 years. Due to this disability, a person loses his ability to work because of long-lasting disorders of biosocial functions. According to literature, occupational therapy for such patients, taking regard to their social, cultural and economic background, significantly increases their self-care and independence and helps to educate working skills. OBJECTIVE. To evaluate conditional disorders of patients with stroke under rehabilitation and to establish the influence of extent of brain damage, localization, age and gender on effectiveness of occupational therapy. Study included 47 men and 53 women diagnosed with brain ischemia or hemorrhage (ischemic or hemorrhagic stroke). Out of them, 30 were of working age (18-59 years old) and 70 of non-working age (more than 60 years old). The mean age was 63.4+/-1.2 years. In order to assess the functional status of patients, they were tested using the Functional Independence Measure (FIM). At the start of rehabilitation, the mean FIM score was 47.4+/-16.1 (48.9+/-15.6 for men and 46.3+/-16.6 for women, p>0.05). At the end of early rehabilitation, the mean FIM score reached up to 89.9+/-22.3 (94.7+/-18.9 for men and 85.7+/-24.3 for women, p<0.05). Evaluation of functional status showed that at the start of rehabilitation functional status was worse in women than men, nevertheless, women's functional status improved during rehabilitation, though the difference between men and women still remained. Occupational therapy was less effective for patients who suffered from hemiplegia than for patients with hemiparesis (p<0.01). Older patients (more than 60 years) had more expressed functional disorders, and worse functional recovery comparing with younger, working age patients (18-59 years old). Evaluation of occupational therapy effectiveness at the end of early rehabilitation showed that extent of brain damage influences independence of patients suffering from brain stroke (p<0.01).

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

NASA Technical Reports Server (NTRS)

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.

An underwater work systems package. [remote handling

NASA Technical Reports Server (NTRS)

Estabrook, N. B.

1975-01-01

A modular unit which is adaptable to several existing deep sea submersibles was developed to extend their working abilities and acquire knowledge of components and techniques for working in the deep sea environment. This work systems package is composed of an aluminum pipe structure on which are mounted two six-function grabber arms, a seven function manipulator, tool suit, 1,000/lb. capacity winch, electrohydraulic power supply, electronics housing, lights, and television. The unit is designed to be operated by itself either remotely or with divers, attached to manned submersibles, or mounted on unmanned cable-controlled submersibles.

Working memory costs of task switching.

PubMed

Liefooghe, Baptist; Barrouillet, Pierre; Vandierendonck, André; Camos, Valérie

2008-05-01

Although many accounts of task switching emphasize the importance of working memory as a substantial source of the switch cost, there is a lack of evidence demonstrating that task switching actually places additional demands on working memory. The present study addressed this issue by implementing task switching in continuous complex span tasks with strictly controlled time parameters. A series of 4 experiments demonstrate that recall performance decreased as a function of the number of task switches and that the concurrent load of item maintenance had no influence on task switching. These results indicate that task switching induces a cost on working memory functioning. Implications for theories of task switching, working memory, and resource sharing are addressed.

RATGRAPH: Computer Graphing of Rational Functions.

ERIC Educational Resources Information Center

Minch, Bradley A.

1987-01-01

Presents an easy-to-use Applesoft BASIC program that graphs rational functions and any asymptotes that the functions might have. Discusses the nature of rational functions, graphing them manually, employing a computer to graph rational functions, and describes how the program works. (TW)

The effect of bupropion XL and escitalopram on memory and functional outcomes in adults with major depressive disorder: results from a randomized controlled trial.

PubMed

Soczynska, Joanna K; Ravindran, Lakshmi N; Styra, Rima; McIntyre, Roger S; Cyriac, Anna; Manierka, Marena S; Kennedy, Sidney H

2014-12-15

Decrements in cognitive function are a common feature of Major Depressive Disorder (MDD), and whether distinct classes of antidepressants differentially affect memory in these individuals has not been sufficiently evaluated. In this study we sought to determine the effect of escitalopram and bupropion XL on memory and psychosocial function. Forty-one individuals (18-50 years) with MDD were enrolled in an 8-week, double-blind, double-dummy, randomized controlled comparative trial of bupropion XL and escitalopram. Thirty-six participants completed pre and post memory assessments. Verbal, non-verbal and working memory were evaluated with a comprehensive neuropsychological battery. Psychosocial function was assessed with the Sheehan Disability Scale and Endicott Work Productivity Scale. Escitalopram and bupropion XL significantly improved immediate as well as delayed verbal and nonverbal memory, global function (all p≤0.001), and work productivity (p=0.045), with no significant between-group differences. Improvement in immediate verbal memory exerted a direct influence on improvement in global function (p=0.006). Treatment with either escitalopram or bupropion XL was associated with improvement in memory and psychosocial function in adults with MDD. Copyright © 2014. Published by Elsevier Ireland Ltd.

Infrared photoemitting diode having reduced work function

DOEpatents

Hirschfeld, T.B.

1982-05-06

In electro-optical detectors which include as elements a photoemitting photocathode and anode, a photoemitting diode is fabricated which lowers the diode's work function, thus reducing the cooling requirement typically needed for this type of device. The work function is reduced by sandwiching between the photocathode and anode a liquid meidum of the formula NR/sub 3/ and having an electron affinity for the electrons of the photocathode, which liquid medium permits free electrons leaving the photocathode to remain as stable solvated species in the liquid medium. Thus, highly light-absorbent, and therefore thin, metallic layers can be used for detection, thereby reducing dark current at a given temperature, with a consequent reduction in cooling requirements at constant detector performance.

Infrared photoemitting diode having reduced work function

DOEpatents

Hirschfeld, Tomas B.

1984-01-01

In electro-optical detectors which include as elements a photoemitting photocathode and anode, a photoemitting diode is fabricated which lowers the diode's work function, thus reducing the cooling requirement typically needed for this type of device. The work function is reduced by sandwiching between the photocathode and anode a liquid medium of the formula NR.sub.3 and having an electron affinity for the electrons of the photocathode, which liquid medium permits free electrons leaving the photocathode to remain as stable solvated species in the liquid medium. Thus, highly light-absorbent, and therefore thin, metallic layers can be used for detection, thereby reducing dark current at a given temperature, with a consequent reduction in cooling requirements at constant detector performance.

Sintered wire cesium dispenser photocathode

DOEpatents

Montgomery, Eric J; Ives, R. Lawrence; Falce, Louis R

2014-03-04

A photoelectric cathode has a work function lowering material such as cesium placed into an enclosure which couples a thermal energy from a heater to the work function lowering material. The enclosure directs the work function lowering material in vapor form through a low diffusion layer, through a free space layer, and through a uniform porosity layer, one side of which also forms a photoelectric cathode surface. The low diffusion layer may be formed from sintered powdered metal, such as tungsten, and the uniform porosity layer may be formed from wires which are sintered together to form pores between the wires which are continuous from the a back surface to a front surface which is also the photoelectric surface.

Understanding the Effect of Plastic Deformation on Elastic Modulus of Metals Based on a Percolation Model with Electron Work Function

NASA Astrophysics Data System (ADS)

Li, Qingda; Hua, Guomin; Lu, Hao; Yu, Bin; Li, D. Y.

2018-05-01

The elastic modulus of materials is usually treated as a constant in engineering applications. However, plastic deformation may result in changes in the elastic modulus of metallic materials. Using brass, aluminum, and low-carbon steel as sample materials, it is demonstrated that plastic deformation decreased the elastic modulus of the materials by 10% to 20%. A percolation model incorporating the electron work function is proposed to correlate such plastic-strain-induced variations in the elastic modulus to corresponding changes in the electron work function. Efforts are made to understand the observed phenomenon on an electronic basis. The obtained experimental results are consistent with the theoretical analysis.

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

Zhukov, A. A., E-mail: azhukov@issp.ac.ru; Chernysheva, M. V.; Eliseev, A. A.

We report the results on the measurements of the work function of single-walled carbon nanotubes encapsulated by Agl (AgI@SWCNT), AgCl (AgCl@SWCNT), and CuBr (CuBr@SWCNT) by the local Kelvin probe technique. We found the values of the work function of tubes encapsulated with AgI and AgCl (Φ(AgI@SWCNT) = 5.08 ± 0.02, Φ(AgCl@SWCNT) = 5.10 ± 0.02 eV) to exceed substantially that of pristine carbon nanotubes, and the value of the work function of carbon nanotubes encapsulated with CuBr is Φ(CuBr@SWCNT) = 4.89 ± 0.03 (eV). The measurements are carried out using different kinds of microscope probes including multi-walled carbon nanotube tips.

High work function transparent middle electrode for organic tandem solar cells

NASA Astrophysics Data System (ADS)

Moet, D. J. D.; de Bruyn, P.; Blom, P. W. M.

2010-04-01

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 of PEDOT:PSS, which does not affect the performance of polythiophene:fullerene solar cells, but results in a lower open-circuit voltage of devices based on a polyfluorene derivative with a higher ionization potential. The introduction of a thin layer of a perfluorinated ionomer recovers the anode work function and gives an open-circuit voltage of 1.92 V for a double junction polyfluorene-based solar cell.

The impact of conscientiousness, mastery, and work circumstances on subsequent absenteeism in employees with and without affective disorders.

PubMed

Kok, Almar A L; Plaisier, Inger; Smit, Johannes H; Penninx, Brenda W J H

2017-03-29

High numbers of employees are coping with affective disorders. At the same time, ambitiousness, achievement striving and a strong sense of personal control and responsibility are personality characteristics that are nowadays regarded as key to good work functioning, whereas social work circumstances tend to be neglected. However, it is largely unkown how personality characteristics and work circumstances affect work functioning when facing an affective disorder. Given the high burden of affective disorders on occupational health, we investigate these issues in the context of affective disorders and absenteeism from work. The principal aim of this paper is to examine whether particular personality characteristics that reflect self-governance (conscientiousness and mastery) and work circumstances (demands, control, support) influence the impact of affective disorders on long-term absenteeism (>10 working days). Baseline and 1-year follow-up data from 1249 participants in the Netherlands Study of Depression and Anxiety (NESDA) in 2004-2006 was employed. Multivariate logistic regression analyses were performed, including interaction effects between depressive, anxiety, and comorbid disorders and personality and work circumstances. In general, mastery and conscientiousness increased nor diminished odds of subsequent long-term absenteeism, whereas higher job support significantly decreased these odds. Interaction effects showed that the impact of affective disorders on absenteeism was stronger for highly conscientious employees and for employees who experienced high job demands. Affective disorders may particularly severely affect work functioning of employees who are highly conscientious or face high psychological job demands. Adjusting working conditions to their individual needs may prevent excessive work absence.

Psychological detachment as moderator between psychosocial work conditions and low back pain development.

PubMed

Mierswa, Tobias; Kellmann, Michael

2017-03-30

Recovery processes in leisure time influence the effect of psychosocial work factors on health issues. However, this function of recovery has been neglected in research regarding the influence of work-related risk factors on low back pain (LBP) development. The aim of this prospective study was to examine the function of psychological detachment - a relevant recovery experience - concerning the influence of psychosocial work factors on LBP development. A moderating function of detachment for the interplay of work factors and LBP was assumed. Sixty pain-free administrative employees of German universities completed an online survey 3 times during a 6-month period. Generalized estimating equations were used to estimate risk-factors of LBP. Analyses revealed an increased chance of LBP development for smokers and a decreasing chance when work resources were high. Detachment had no direct influence on LBP development, although it moderated the influence of work stressors and work resources on LBP. On the one hand, high detachment values seem to protect against an increased chance of LBP development when employees were confronted with high work stressors, while on the other hand high detachment values enhance the protective effect of high work resources. The results indicated a moderating role of detachment concerning the influence of psychosocial work factors on LBP development. Therefore, it is necessary to include recovery processes in future research regarding LBP development and consequently in LBP prevention concepts. Int J Occup Med Environ Health 2017;30(2):313-327. This work is available in Open Access model and licensed under a CC BY-NC 3.0 PL license.

Constructing a working taxonomy of functional Ada software components for real-time embedded system applications

NASA Technical Reports Server (NTRS)

Wallace, Robert

1986-01-01

A major impediment to a systematic attack on Ada software reusability is the lack of an effective taxonomy for software component functions. The scope of all possible applications of Ada software is considered too great to allow the practical development of a working taxonomy. Instead, for the purposes herein, the scope of Ada software application is limited to device and subsystem control in real-time embedded systems. A functional approach is taken in constructing the taxonomy tree for identified Ada domain. The use of modular software functions as a starting point fits well with the object oriented programming philosophy of Ada. Examples of the types of functions represented within the working taxonomy are real time kernels, interrupt service routines, synchronization and message passing, data conversion, digital filtering and signal conditioning, and device control. The constructed taxonomy is proposed as a framework from which a need analysis can be performed to reveal voids in current Ada real-time embedded programming efforts for Space Station.

The geography and human cultural resources working group of the EROS program

NASA Technical Reports Server (NTRS)

Gerlach, A. C.

1972-01-01

The functions, activities, and objectives of the Geography and Human-Cultural Resources Working Group of the EROS program are outlined. The Group's primary function is to coordinate remote sensing experiments of physical scientists and the needs of socioeconomic and culturally orientated planners, policy makers, administrators, and other user groups. Other functions of the Group include land use analysis, resource mapping, and development of an operational automatic information system receptive to land use and environmental data.

A longitudinal study of computerized cognitive training in stroke patients - effects on cognitive function and white matter.

PubMed

Nyberg, Claudia Kim; Nordvik, Jan Egil; Becker, Frank; Rohani, Darius A; Sederevicius, Donatas; Fjell, Anders M; Walhovd, Kristine B

2018-05-01

Background Computerized cognitive training is suggested to enhance attention and working memory functioning following stroke, but effects on brain and behavior are not sufficiently studied and longitudinal studies assessing brain and behavior relationships are scarce. Objective The study objectives were to investigate relations between neuropsychological performance post-stroke and white matter microstructure measures derived from diffusion tensor imaging (DTI), including changes after 6 weeks of working memory training. Methods In this experimental training study, 26 stroke patients underwent DTI and neuropsychological tests at 3 time points - before and after a passive phase of 6 weeks, and again after 6 weeks of working memory training (Cogmed QM). Fractional anisotropy (FA) was extracted from stroke-free brain areas to assess the white matter microstructure. Twenty-two participants completed the majority of training (≥18/25 sessions) and were entered into longitudinal analyses. Results Significant correlations between FA and baseline cognitive functions were observed (r = 0.58, p = 0.004), however, no evidence was found of generally improved cognitive functions following training or of changes in white matter microstructure. Conclusions While white matter microstructure related to baseline cognitive function in stroke patients, the study revealed no effect on cognitive functions or microstructural changes in white matter in relation to computerized working memory training.

Differences in the verbal fluency, working memory and executive functions in alcoholics: Short-term vs. long-term abstainers.

PubMed

Nowakowska-Domagała, Katarzyna; Jabłkowska-Górecka, Karolina; Mokros, Łukasz; Koprowicz, Jacek; Pietras, Tadeusz

2017-03-01

The aim of the study was to assess differences in verbal fluency, working memory and executive functions in two subgroups of alcohol-dependent patients, those undergoing short-term abstinence (STA) and those undergoing long-term abstinence (LTA), and to compare the level of cognitive functions in patients after long-term abstinence with healthy subjects. The study group consisted of 106 alcohol-dependent patients (53 immediately after drinking at least 3 days and 53 after at least one-year abstinence). The control group comprised 53 subjects, whose age, sex and education levels matched those of the patients in the experimental group. The dependence intensity was assessed using SADD and MAST scales. The neuropsychological assessment was based on the FAS Test, Stroop Test and TMT A&B Test. The results obtained for alcohol-dependent patients revealed significant disturbances of cognitive functions. Such results indicate the presence of severe frontal cerebral cortex dysfunctions. Frontal cortex dysfunctions affecting the verbal fluency and working memory subsystems and the executive functions also persisted during long-term abstinence periods. No significant correlations between the duration of dependence, quantity of alcohol consumed and efficiency of the working memory and executive functions were observed in alcohol-dependent subjects after short-term or long-term abstinence. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.

PTSD symptom severity relates to cognitive and psycho-social dysfunctioning – a study with Congolese refugees in Uganda

PubMed Central

Ainamani, Herbert E.; Elbert, Thomas; Olema, David K.; Hecker, Tobias

2017-01-01

ABSTRACT Background: In the ongoing conflict in the Democratic Republic of the Congo (DRC), civilians have been heavily exposed to traumatic stressors. Traumatizing experiences cumulatively heighten the risk for trauma-related disorders, and with it affect cognitive and psycho-social functioning. Objectives: We aimed at investigating the association between trauma-related disorders and cognitive and psycho-social functioning and hypothesized that PTSD symptom severity would negatively correlate with executive functioning, working memory and psycho-social functioning in everyday life. Method: In total, 323 Congolese refugees (mean age: 31.3 years) who arrived in the Ugandan Nakivale refugee settlement after January 2012 were assessed regarding their exposure to traumatic events, PTSD symptom severity (posttraumatic symptom scale interview), executive functioning (Tower of London), working memory performance (Corsi block tapping task) and psycho-social dysfunctioning (Luo functioning scale). Results: Hierarchical regression analyses indicated a significant negative association between PTSD symptom severity and working memory (β = –0.32, p < 0.001), as well as executive functions (β = –0.19, p = 0.003). Furthermore, the impairment of psycho-social functioning in everyday life was positively related with PTSD symptom severity (β = 0.70, p < 0.001), and negatively with executive functioning (β = –0.15, p = 0.003). However, working memory performance was not significantly related to psycho-social dysfunctioning (β = 0.09, p > 0.05). Conclusion: Trauma survivors not only suffer from the core PTSD symptoms but also from impaired cognitive functioning. PTSD symptom severity seems furthermore to be related to impaired psycho-social functioning. Our findings suggest that trauma-related mental health problems may heighten the risk for poverty and lack of prospect and further aggravate the consequences of war and conflict. PMID:28326164

Reciprocal Relations between Work-Related Authenticity and Intrinsic Motivation, Work Ability and Depressivity: A Two-Wave Study

PubMed Central

Emmerich, Astrid I.; Rigotti, Thomas

2017-01-01

This study investigates the role of context-specific authenticity at work for work-related outcomes (intrinsic motivation, work ability) and depressivity. Furthermore reciprocal relations between work-related authenticity and healthy psychological functioning are investigated. Longitudinal data from 1,243 employees from 63 subsidiaries of a non-profit organization in the social sector were analyzed using multilevel structural equation modeling. Work-related authenticity at T1 predicted work ability and depressivity, but not intrinsic motivation at T2, about 6 months later. Work-related authenticity at T2 was predicted by intrinsic motivation and depressivity, but not by work ability at T1. We conclude that work-related authenticity and healthy psychological functioning are positively reinforcing each other. Thus, enabling employees to be authentic supposedly increases their well-being and is a pivotal opportunity for organizations to foster health and performance-related indicators like work ability and prevent negative health indicators like depressivity. At the same time, authenticity of employees can be fostered through workplace health promotion. PMID:28316581

An integrative model of evolutionary covariance: a symposium on body shape in fishes.

PubMed

Walker, Jeffrey A

2010-12-01

A major direction of current and future biological research is to understand how multiple, interacting functional systems coordinate in producing a body that works. This understanding is complicated by the fact that organisms need to work well in multiple environments, with both predictable and unpredictable environmental perturbations. Furthermore, organismal design reflects a history of past environments and not a plan for future environments. How complex, interacting functional systems evolve, then, is a truly grand challenge. In accepting the challenge, an integrative model of evolutionary covariance is developed. The model combines quantitative genetics, functional morphology/physiology, and functional ecology. The model is used to convene scientists ranging from geneticists, to physiologists, to ecologists, to engineers to facilitate the emergence of body shape in fishes as a model system for understanding how complex, interacting functional systems develop and evolve. Body shape of fish is a complex morphology that (1) results from many developmental paths and (2) functions in many different behaviors. Understanding the coordination and evolution of the many paths from genes to body shape, body shape to function, and function to a working fish body in a dynamic environment is now possible given new technologies from genetics to engineering and new theoretical models that integrate the different levels of biological organization (from genes to ecology).

Longitudinal Associations Between Formal Volunteering and Cognitive Functioning.

PubMed

Proulx, Christine M; Curl, Angela L; Ermer, Ashley E

2018-03-02

The present study examines the association between formal volunteering and cognitive functioning over time. We also examine the moderating roles of race, sex, education, and time. Using 11,100 participants aged 51 years and older and nine waves of data from the Health and Retirement Survey, we simultaneously modeled the longitudinal associations between engaging in formal volunteering and changes in cognitive functioning using multilevel models. Formal volunteering was associated with higher levels of cognitive functioning over time, especially with aspects of cognitive functioning related to working memory and processing. This association was stronger for women than it was for men, and for those with below average levels of education. The positive association between formal volunteering and cognitive functioning weakened over time when cognitive functioning was conceptualized as memory, but strengthened over time when conceptualized as working memory and processing. Volunteering is a productive activity that is beneficial not just to society, but to volunteers' levels of cognitive functioning in older age. For women and those with lower levels of education, formal volunteering appears particularly beneficial to working memory and processing. © The Author 2017. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Applying an Integrative Framework of Executive Function to Preschoolers With Specific Language Impairment

PubMed Central

Plante, Elena; Doubleday, Kevin

2017-01-01

Purpose The first goal of this research was to compare verbal and nonverbal executive function abilities between preschoolers with and without specific language impairment (SLI). The second goal was to assess the group differences on 4 executive function components in order to determine if the components may be hierarchically related as suggested within a developmental integrative framework of executive function. Method This study included 26 4- and 5-year-olds diagnosed with SLI and 26 typically developing age- and sex-matched peers. Participants were tested on verbal and nonverbal measures of sustained selective attention, working memory, inhibition, and shifting. Results The SLI group performed worse compared with typically developing children on both verbal and nonverbal measures of sustained selective attention and working memory, the verbal inhibition task, and the nonverbal shifting task. Comparisons of standardized group differences between executive function measures revealed a linear increase with the following order: working memory, inhibition, shifting, and sustained selective attention. Conclusion The pattern of results suggests that preschoolers with SLI have deficits in executive functioning compared with typical peers, and deficits are not limited to verbal tasks. A significant linear relationship between group differences across executive function components supports the possibility of a hierarchical relationship between executive function skills. PMID:28724132

Working Memory: Maintenance, Updating, and the Realization of Intentions

PubMed Central

Nyberg, Lars; Eriksson, Johan

2016-01-01

“Working memory” refers to a vast set of mnemonic processes and associated brain networks, relates to basic intellectual abilities, and underlies many real-world functions. Working-memory maintenance involves frontoparietal regions and distributed representational areas, and can be based on persistent activity in reentrant loops, synchronous oscillations, or changes in synaptic strength. Manipulation of content of working memory depends on the dorsofrontal cortex, and updating is realized by a frontostriatal ‘“gating” function. Goals and intentions are represented as cognitive and motivational contexts in the rostrofrontal cortex. Different working-memory networks are linked via associative reinforcement-learning mechanisms into a self-organizing system. Normal capacity variation, as well as working-memory deficits, can largely be accounted for by the effectiveness and integrity of the basal ganglia and dopaminergic neurotransmission. PMID:26637287

Self-Regulation, Executive Function, Working Memory, and Academic Achievement of Female High School Students

ERIC Educational Resources Information Center

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…

Work and Supervisor Satisfaction as a Function of Subordinate Perceptions of Communication Competence of Self and Supervisor.

ERIC Educational Resources Information Center

Smith, Anthony F.; Hellweg, Susan A.

A study investigated relationships between subordinate perceptions of the communication competence of self and supervisor, and subordinate perceptions of supervisor and work satisfaction. The hypotheses were the following: (1) subordinates' satisfaction with their supervisors will vary as a function of their perceptions of their supervisors'…

Applying Cognitive Work Analysis to Time Critical Targeting Functionality

DTIC Science & Technology

2004-10-01

Cognitive Task Analysis , CTA, Cognitive Task Analysis , Human Factors, GUI, Graphical User Interface, Heuristic Evaluation... Cognitive Task Analysis MITRE Briefing January 2000 Dynamic Battle Management Functional Architecture 3-1 Section 3 Human Factors...clear distinction between Cognitive Work Analysis (CWA) and Cognitive Task Analysis (CTA), therefore this document will refer to these

Evaluating Experiential Learning in the Business Context: Contributions to Group-Based and Cross-Functional Working

ERIC Educational Resources Information Center

Piercy, Niall

2013-01-01

The use of experiential learning techniques has become popular in business education. Experiential learning approaches offer major benefits for teaching contemporary management practices such as cross-functional and team-based working. However, there remains relatively little empirical data on the success of experiential pedagogies in supporting…

Are the Correlates of Children's Internal Working Models of Attachment Gender Specific?

ERIC Educational Resources Information Center

Broberg, Anders G.; Wiberg, Charlotta; Gyland, Patrik; Ramsby, Louise; Bohlin, Gunilla; Rydell, Ann-Margret

Noting that gender may be an important issue when studying relations between attachment and social functioning, four studies explored whether the relationship between children's internal working models of attachment and their general functioning was gender specific. A total of 246 children, ages 5 to 10 years, were given the Separation Anxiety…

The Influence of Domain Knowledge on the Functional Capacity of Working Memory

ERIC Educational Resources Information Center

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…

Preparing Transition-Age Students with High-Functioning Autism Spectrum Disorders for Meaningful Work

ERIC Educational Resources Information Center

Lee, Gloria K.; Carter, Erik W.

2012-01-01

This article provides an overview of promising essential elements for fostering vocational success among students with high-functioning autism spectrum disorders (HFASDs) by drawing literature from the fields of school-to-work transition for post-secondary students and vocational rehabilitation for individuals with disabilities. We highlight seven…

The influence of temperature on the work function of W, LaB 6 and pseudo-alloys

NASA Astrophysics Data System (ADS)

Bulyga, A. V.; Solonovich, V. K.

1989-12-01

The experimental temperature dependences α f = d F/d T of the work function F = F( T) for W(111), LaB 6(100) and W-Ni-LaB 6 pseudo-alloy surfaces emitting thermoelectrons are compared with α f predicted by the Hohenberg-Lang-Kohn theory.

Load Modulation of BOLD Response and Connectivity Predicts Working Memory Performance in Younger and Older Adults

ERIC Educational Resources Information Center

Nagel, Irene E.; Preuschhof, Claudia; Li, Shu-Chen; Nyberg, Lars; Backman, Lars; Lindenberger, Ulman; Heekeren, Hauke R.

2011-01-01

Individual differences in working memory (WM) performance have rarely been related to individual differences in the functional responsivity of the WM brain network. By neglecting person-to-person variation, comparisons of network activity between younger and older adults using functional imaging techniques often confound differences in activity…

Finance Project. Status Report and Preliminary Working Papers.

ERIC Educational Resources Information Center

California Community Colleges, Sacramento. Office of the Chancellor.

This status report outlines the progress of the California Community College Finance Project. Working papers, models, and alternative proposals are reviewed in four areas: mission and function, finance, governance, and management. Priorities in mission and function are stated in terms of the characteristics and educational needs of the nearly 1.3…

Dialogic Space: Intersections between Dialogic Teaching and Systemic Functional Linguistics

ERIC Educational Resources Information Center

Hammond, Jennifer

2016-01-01

The aim of this article is to foster dialogue between proponents of Alexander's notion of dialogic teaching and those working with educational linguistics--in particular those working with systemic functional theory. To this end, the article begins by highlighting important points of alignment between dialogic teaching and systemic theory: their…

Utility of the International Classification of Functioning, Disability and Health (ICF) for Educational Psychologists' Work

ERIC Educational Resources Information Center

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…

A Student's Construction of Transformations of Functions in a Multiple Representational Environment.

ERIC Educational Resources Information Center

Borba, Marcelo C.; Confrey, Jere

1996-01-01

Reports on a case study of a 16-year-old student working on transformations of functions in a computer-based, multirepresentational environment. Presents an analysis of the work during the transition from the use of visualization and analysis of discrete points to the use of algebraic symbolism. (AIM)

Aluminum work function: Effect of oxidation, mechanical scraping and ion bombardment

NASA Technical Reports Server (NTRS)

Vinet, P.; Lemogne, T.; Montes, H.

1985-01-01

Surface studies have been performed on aluminum polycrystalline surfaces which have been mechanically scraped. Such studies were initiated in order to understand surface effects occurring in tribological processes which involve rubbing surfaces and the effects of adsorption of oxygen. To characterize the surfaces, the following three different experimental approaches have been used: (1) X.P.S. (X-ray photoelectron spectroscopy), in order to check the cleanliness of the surfaces and follow the adsorption and oxidation kinetics; (2) Analysis of the work function changes by following the energy spectra of secondary electrons emitted under low energy electron bombardment; and (3) Analysis of photoemission intensities under U.V. excitation. The reference state being chosen to be the surface cleaned by ion bombardment and exposures to oxygen atmospheres have been shown to lower the work function of clean polycrystalline aluminum by 1.2 eV. The oxygen pressure is found to affect only the kinetics of these experiments. Mechanical scraping has been shown to induce a decrease ( 0.3 eV) in the work function, which could sharply modify the kinetics of adsorption on the surface.

Thermionic converter

DOEpatents

Rasor, Ned S.; Britt, Edward J.

1976-01-01

A gas-filled thermionic converter is provided with a collector and an emitter having a main emitter region and an auxiliary emitter region in electrical contact with the main emitter region. The main emitter region is so positioned with respect to the collector that a main gap is formed therebetween and the auxiliary emitter region is so positioned with respect to the collector that an auxiliary gap is formed therebetween partially separated from the main gap with access allowed between the gaps to allow ionizable gas in each gap to migrate therebetween. With heat applied to the emitter the work function of the auxiliary emitter region is sufficiently greater than the work function of the collector so that an ignited discharge occurs in the auxiliary gap and the work function of the main emitter region is so related to the work function of the collector that an unignited discharge occurs in the main gap sustained by the ions generated in the auxiliary gap. A current flows through a load coupled across the emitter and collector due to the unignited discharge in the main gap.

DC and analog/RF performance optimisation of source pocket dual work function TFET

NASA Astrophysics Data System (ADS)

Raad, Bhagwan Ram; Sharma, Dheeraj; Kondekar, Pravin; Nigam, Kaushal; Baronia, Sagar

2017-12-01

We investigate a systematic study of source pocket tunnel field-effect transistor (SP TFET) with dual work function of single gate material by using uniform and Gaussian doping profile in the drain region for ultra-low power high frequency high speed applications. For this, a n+ doped region is created near the source/channel junction to decrease the depletion width results in improvement of ON-state current. However, the dual work function of the double gate is used for enhancement of the device performance in terms of DC and analog/RF parameters. Further, to improve the high frequency performance of the device, Gaussian doping profile is considered in the drain region with different characteristic lengths which decreases the gate to drain capacitance and leads to drastic improvement in analog/RF figures of merit. Furthermore, the optimisation is performed with different concentrations for uniform and Gaussian drain doping profile and for various sectional length of lower work function of the gate electrode. Finally, the effect of temperature variation on the device performance is demonstrated.

Reduced prefrontal efficiency for visuospatial working memory in attention-deficit/hyperactivity disorder.

PubMed

Bédard, Anne-Claude V; Newcorn, Jeffrey H; Clerkin, Suzanne M; Krone, Beth; Fan, Jin; Halperin, Jeffrey M; Schulz, Kurt P

2014-09-01

Visuospatial working memory impairments have been implicated in the pathophysiology of attention-deficit/hyperactivity disorder (ADHD). However, most ADHD research has focused on the neural correlates of nonspatial mnemonic processes. This study examined brain activation and functional connectivity for visuospatial working memory in youth with and without ADHD. Twenty-four youth with ADHD and 21 age- and sex-matched healthy controls were scanned with functional magnetic resonance imaging while performing an N-back test of working memory for spatial position. Block-design analyses contrasted activation and functional connectivity separately for high (2-back) and low (1-back) working memory load conditions versus the control condition (0-back). The effect of working memory load was modeled with linear contrasts. The 2 groups performed comparably on the task and demonstrated similar patterns of frontoparietal activation, with no differences in linear gains in activation as working memory load increased. However, youth with ADHD showed greater activation in the left dorsolateral prefrontal cortex (DLPFC) and left posterior cingulate cortex (PCC), greater functional connectivity between the left DLPFC and left intraparietal sulcus, and reduced left DLPFC connectivity with left midcingulate cortex and PCC for the high load contrast compared to controls (p < .01; k > 100 voxels). Reanalysis using a more conservative statistical approach (p < .001; k > 100 voxels) yielded group differences in PCC activation and DLPFC-midcingulate connectivity. Youth with ADHD show decreased efficiency of DLPFC for high-load visuospatial working memory and greater reliance on posterior spatial attention circuits to store and update spatial position than healthy control youth. Findings should be replicated in larger samples. Copyright © 2014 American Academy of Child and Adolescent Psychiatry. Published by Elsevier Inc. All rights reserved.

Agricultural work exposures and pulmonary function among hired farm workers in California (the MICASA study).

PubMed

Rodriquez, Erik J; Stoecklin-Marois, Maria T; Bennett, Deborah H; Tancredi, Daniel J; Schenker, Marc B

2014-01-01

Despite California's dependence on hired farm labor, scarce research has been conducted on the respiratory health of hired farm workers. Agricultural exposures to inorganic and organic dusts can adversely affect an individual's respiratory health and differ by farm type and job task. The purpose of the present analysis was to examine associations between agricultural work exposures and pulmonary function among 450 California farm workers. Data were collected as part of the Mexican Immigration to California: Agricultural Safety and Acculturation (MICASA) study, a prospective cohort study examining occupational risk factors and health of hired farm worker families in Mendota, California. Time-weighted self-reported average (TWSRA) dust scores were calculated from assessments of past-12-month agricultural work history. Other dust exposure indicator variables included months worked in agriculture in the past 12 months and years worked in agriculture. Multiple linear regression modeled FEV1 (forced expiratory volume in 1 second), FEF(25-75%) (forced midexpiratory flow rate), FVC (forced vital capacity), FEV6, FEV1/FVC, and FEV1/FEV6 separately. Seventy-six percent of participants had worked in agriculture in the past year. In models conducted for crops and tasks separately, high TWSRA dust score was associated with better FEV6. Crop and task models showed associations between greater months worked in agriculture in the past year and better FEV1, FEF(25-75%), and FEV6. Both models also found greater years worked in agriculture to be associated with worse FEV1/FEV6. Results were generally in the opposite direction as expected given past research but not uncommon. Future research should investigate relationships between pulmonary function and agricultural dust exposure over a lifetime and changes in pulmonary function over time.

Altered Right Ventricular Kinetic Energy Work Density and Viscous Energy Dissipation in Patients with Pulmonary Arterial Hypertension: A Pilot Study Using 4D Flow MRI.

PubMed

Han, Q Joyce; Witschey, Walter R T; Fang-Yen, Christopher M; Arkles, Jeffrey S; Barker, Alex J; Forfia, Paul R; Han, Yuchi

2015-01-01

Right ventricular (RV) function has increasingly being recognized as an important predictor for morbidity and mortality in patients with pulmonary arterial hypertension (PAH). The increased RV after-load increase RV work in PAH. We used time-resolved 3D phase contrast MRI (4D flow MRI) to derive RV kinetic energy (KE) work density and energy loss in the pulmonary artery (PA) to better characterize RV work in PAH patients. 4D flow and standard cardiac cine images were obtained in ten functional class I/II patients with PAH and nine healthy subjects. For each individual, we calculated the RV KE work density and the amount of viscous dissipation in the PA. PAH patients had alterations in flow patterns in both the RV and the PA compared to healthy subjects. PAH subjects had significantly higher RV KE work density than healthy subjects (94.7±33.7 mJ/mL vs. 61.7±14.8 mJ/mL, p = 0.007) as well as a much greater percent PA energy loss (21.1±6.4% vs. 2.2±1.3%, p = 0.0001) throughout the cardiac cycle. RV KE work density and percent PA energy loss had mild and moderate correlations with RV ejection fraction. This study has quantified two kinetic energy metrics to assess RV function using 4D flow. RV KE work density and PA viscous energy loss not only distinguished healthy subjects from patients, but also provided distinction amongst PAH patients. These metrics hold promise as imaging markers for RV function.

Arithmetic difficulties in children with cerebral palsy are related to executive function and working memory.

PubMed

Jenks, Kathleen M; de Moor, Jan; van Lieshout, Ernest C D M

2009-07-01

Although it is believed that children with cerebral palsy are at high risk for learning difficulties and arithmetic difficulties in particular, few studies have investigated this issue. Arithmetic ability was longitudinally assessed in children with cerebral palsy in special (n = 41) and mainstream education (n = 16) and controls in mainstream education (n = 16). Second grade executive function and working memory scores were used to predict third grade arithmetic accuracy and response time. Children with cerebral palsy in special education were less accurate and slower than their peers on all arithmetic tests, even after controlling for IQ, whereas children with cerebral palsy in mainstream education performed as well as controls. Although the performance gap became smaller over time, it did not disappear. Children with cerebral palsy in special education showed evidence of executive function and working memory deficits in shifting, updating, visuospatial sketchpad and phonological loop (for digits, not words) whereas children with cerebral palsy in mainstream education only had a deficit in visuospatial sketchpad. Hierarchical regression revealed that, after controlling for intelligence, components of executive function and working memory explained large proportions of unique variance in arithmetic accuracy and response time and these variables were sufficient to explain group differences in simple, but not complex, arithmetic. Children with cerebral palsy are at risk for specific executive function and working memory deficits that, when present, increase the risk for arithmetic difficulties in these children.

Psychometric properties of the Nurses Work Functioning Questionnaire (NWFQ).

PubMed

Gärtner, Fania R; Nieuwenhuijsen, Karen; van Dijk, Frank J H; Sluiter, Judith K

2011-01-01

The Nurses Work Functioning Questionnaire (NWFQ) is a 50-item self-report questionnaire specifically developed for nurses and allied health professionals. Its seven subscales measure impairments in the work functioning due to common mental disorders. Aim of this study is to evaluate the psychometric properties of the NWFQ, by assessing reproducibility and construct validity. The questionnaire was administered to 314 nurses and allied health professionals with a re-test in 112 subjects. Reproducibility was assessed by the intraclass correlations coefficients (ICC) and the standard error of measurement (SEM). For construct validity, correlations were calculated with a general work functioning scale, the Endicott Work Productivity Scale (EWPS) (convergent validity) and with a physical functioning scale (divergent validity). For discriminative validity, a Mann Whitney U test was performed testing for significant differences between subjects with mental health complaints and without. All subscales showed good reliability (ICC: 0.72-0.86), except for one (ICC = 0.16). Convergent validity was good in six subscales, correlations ranged from 0.38-0.62. However, in one subscale the correlation with the EWPS was too low (0.22). Divergent validity was good in all subscales based on correlations ranged from (-0.06)-(-0.23). Discriminative validity was good in all subscales, based on significant differences between subjects with and without mental health complaints (p<0.001-p = 0.003). The NWFQ demonstrates good psychometric properties, for six of the seven subscales. Subscale "impaired decision making" needs improvement before further use.

[P. K. Anokhin--creator of the theory of the functional system].

PubMed

Golubeva, E L

1997-01-01

Memories about scientific activities of P. K. Anokhin cover "Gorbi" period of his work, pre-war work in VIEM in (All-Union Institute of Experimental Medicine) Moscow, renew of researches the war (1944-1952), stress the losses, caused by scientific session, devoted to problems of I. P. Pavlov physiological doctrine in 1950. Indicated roots and ways of forming of functional system theory and system genesis conception. Overview of scientific works, belong to academics, headed by P. K. Anokhin.

[Evaluation of residual osteomuscular function using computerised movement analysis for building sector workers: specificity and technical problem].

PubMed

D'Orso, M I; Centemeri, R; Latocca, R; Riva, M; Cesana, G

2012-01-01

Occupational Health Doctors active in building sector firms frequently have to evaluate residual workers' osteomuscular function in patients coming back to work after an accident happened during work time or free time. Definition of their specific individual work suitability is usually carried out utilizing semeiotic tests in which subjective evaluation of every single Medical Doctor is real important in definition of final results and this fact can cause legal controversies. In our research we describe the application of computerised movement analysis on 10 workers of building sector. In every patient examined this technical method has been able to study objectively the tridimensional ranges of motion of most important osteomuscular districts. The possibility to have an objective evaluation of residual osteomuscular function has a relevant importance both in definition of workers' work suitability at the moment in which they start again their activities and in possible future legal conflicts.

The association of medical conditions and presenteeism.

PubMed

Burton, Wayne N; Pransky, Glenn; Conti, Daniel J; Chen, Chin-Yu; Edington, Dee W

2004-06-01

A self-reported measure of four domains of work impairment based on the Work Limitations Questionnaire was completed by 16,651 employees of a large financial services corporation. Using a multivariate model to control for coexisting conditions, age, and gender, significant relationships were observed between medical conditions and patterns of impaired work performance. Depression was highly associated with work limitations in time management (odds ratio [OR] = 2.05), interpersonal/mental functioning (OR = 2.50), and overall output (OR = 2.24). Arthritis (OR = 1.56) and low back pain (OR = 1.32) were associated with physical function limitations. These same two conditions were associated with limitations in mental/interpersonal functioning but with low back pain having the higher odds ratio (OR = 1.54 vs. 1.22). These results suggest that worksite interventions (eg, disease management programs) should be tailored to the unique effects observed with specific medical conditions. More targeted programs could have important benefits for productivity in the workplace.

Examining the Roles of Work Autonomous and Controlled Motivations on Satisfaction and Anxiety as a Function of Role Ambiguity.

PubMed

Gillet, Nicolas; Fouquereau, Evelyne; Lafrenière, Marc-André K; Huyghebaert, Tiphaine

2016-07-03

Past research in the self-determination theory has shown that autonomous motivation is associated with positive outcomes (e.g., work satisfaction), whereas controlled motivation is related to negative outcomes (e.g., anxiety). The purpose of the present research was to examine the moderating function of role ambiguity on the relationships between work autonomous and controlled motivations on the one hand, and work satisfaction and anxiety on the other. Six hundred and ninety-eight workers (449 men and 249 women) participated in this study. Results revealed that autonomous motivation was most strongly related to satisfaction when ambiguity was low. In addition, controlled motivation was most strongly related to anxiety when ambiguity was high. In other words, the present findings suggest that the outcomes associated with each form of motivation may vary as a function of role ambiguity. The present study thus offers meaningful insights for organizations, managers, and employees.

Aircraft Flight Modeling During the Optimization of Gas Turbine Engine Working Process

NASA Astrophysics Data System (ADS)

Tkachenko, A. Yu; Kuz'michev, V. S.; Krupenich, I. N.

2018-01-01

The article describes a method for simulating the flight of the aircraft along a predetermined path, establishing a functional connection between the parameters of the working process of gas turbine engine and the efficiency criteria of the aircraft. This connection is necessary for solving the optimization tasks of the conceptual design stage of the engine according to the systems approach. Engine thrust level, in turn, influences the operation of aircraft, thus making accurate simulation of the aircraft behavior during flight necessary for obtaining the correct solution. The described mathematical model of aircraft flight provides the functional connection between the airframe characteristics, working process of gas turbine engines (propulsion system), ambient and flight conditions and flight profile features. This model provides accurate results of flight simulation and the resulting aircraft efficiency criteria, required for optimization of working process and control function of a gas turbine engine.

Evaluation of impairment of the upper extremity.

PubMed

Blair, S J; McCormick, E; Bear-Lehman, J; Fess, E E; Rader, E

1987-08-01

Evaluation of impairment of the upper extremity is the product of a team effort by the physician, occupational therapist, physical therapist, and rehabilitation counselor. A careful recording of the anatomic impairment should be made because this is critical in determining the subsequent functional activities of the extremity. The measurement criteria for clinical and functional evaluation includes condition assessment instruments. Some assess the neurovascular system, others assess movements including the monitoring of articular motion and musculotendinous function. Sensibility assessment instruments measure sympathetic response and detect single joint stimulus, discrimination, quantification, and recognition abilities. A detailed description of each assessment is recorded and physical capacity evaluation is only one component of the entire vocational evaluation. This evaluation answers questions regarding the injured worker's ability to return to his previous job. The work simulator is a useful instrument that allows rehabilitation and testing of the injured upper extremity. Job site evaluation includes assessment criteria for work performance, work behavior, and work environment.

Sequenced neurocognitive and behavioral parent training for the treatment of ADHD in school-age children.

PubMed

Chacko, A; Bedard, A-C V; Marks, D; Gopalan, G; Feirsen, N; Uderman, J; Chimiklis, A; Heber, E; Cornwell, M; Anderson, L; Zwilling, A; Ramon, M

2018-05-01

The present study examines the potential of sequencing a neurocognitive intervention with behavioral parent training (BPT) to improve executive functions (EFs), psychiatric symptoms, and multiple indices of functional impairment in school-age children aged 7 to 11 years who have been diagnosed with attention-deficit/hyperactivity disorder (ADHD). Specifically, in a randomized controlled trial design, 85 children were assigned to either Cogmed Working Memory Training (CWMT) followed by an empirically supported, manualized BPT intervention, or to a placebo version of CWMT followed by the same BPT intervention. Working memory maintenance (i.e., attention control/short-term memory), working memory processing and manipulation, ADHD and oppositional defiant disorder (ODD) symptoms, impairment in parent-child dynamics, familial impairment, and overall functional compromise were evaluated as outcomes. The results suggest specific effects of the combined CWMT and BPT program on verbal and nonverbal working memory storage and nonverbal working memory processing and manipulation but no incremental benefits in regard to ADHD symptoms, ODD symptoms, and functional outcomes. The present findings do not support the hypothesis regarding the complementary and augmentative benefits of sequenced neurocognitive and BPT interventions for the treatment of ADHD. These results, the study's limitations, and future directions for research are further discussed.

Functional and environmental factors affecting work status in individuals with longstanding poliomyelitis.

PubMed

Zeilig, Gabi; Weingarden, Harold; Shemesh, Yeheskel; Herman, Amir; Heim, Michael; Zeweker, Manual; Dudkiewicz, Israel

2012-01-01

Remunerative employment is a major concern of individuals with chronic disabilities, among them, those with longstanding poliomyelitis (LSP). Although LSP is not rare there are almost no data related to work participation. The aims of the current study were to determine the effects of a number of social and functional variables as barriers or facilitators to work participation in persons with LSP. Charts of 123 LSP patients of working age that were seen in the post-polio outpatient clinic, between the years 2000 and 2005 were reviewed for the study. Data on age, gender, family status, level of function in activities of daily living, basic, and extended (B-ADL and E-ADL), and mobility were then analyzed for correlation to the vocational status. Seventy-two people (58.5%) were employed at the time of the survey. Gender and marital status were not found to significantly differ as regard to employment. Using assistive devices for mobility or being dependent for basic ADL were associated with lower levels of employment. Driving was positively associated with the employment status of the LSP individuals. Persons with LSP encounter important barriers to work participation, particularly on the International Classification of Functioning, Disability, and Health (ICF) components of activity and environment.

COPRED: prediction of fold, GO molecular function and functional residues at the domain level.

PubMed

López, Daniel; Pazos, Florencio

2013-07-15

Only recently the first resources devoted to the functional annotation of proteins at the domain level started to appear. The next step is to develop specific methodologies for predicting function at the domain level based on these resources, and to implement them in web servers to be used by the community. In this work, we present COPRED, a web server for the concomitant prediction of fold, molecular function and functional sites at the domain level, based on a methodology for domain molecular function prediction and a resource of domain functional annotations previously developed and benchmarked. COPRED can be freely accessed at http://csbg.cnb.csic.es/copred. The interface works in all standard web browsers. WebGL (natively supported by most browsers) is required for the in-line preview and manipulation of protein 3D structures. The website includes a detailed help section and usage examples. pazos@cnb.csic.es.

Gender differences in job strain, effort-reward imbalance, and health functioning among Chinese physicians.

PubMed

Li, Jian; Yang, Wenjie; Cho, Sung-Il

2006-03-01

To examine the association between work stress measured by job strain and effort-reward imbalance (ERI) and health functioning in a sample of hospital-based Chinese physicians, a self-reported survey with a standardized questionnaire was conducted in three hospitals in China, among 256 men and 266 women. It was found that both job strain and ERI were associated with impaired health functioning in men and women, but that ERI indicated a stronger association. Men's job control was significantly higher, and was related to men's physical health; whereas women perceived relatively higher job reward which predicted women's mental health. The findings provide evidence of the adverse effects on health functioning of both job strain and ERI, but ERI appears to have more explanatory power as a model of work stress in this sample of Chinese physicians. In addition, gender differences of work stress with respect to health are present.

Altered cognitive development in the siblings of individuals with schizophrenia

PubMed Central

Barch, Deanna M.; Cohen, Rachel; Csernansky, John

2014-01-01

The goal of the current study was to further investigate the late neurodevelopmental hypothesis of schizophrenia by examining cross-sectional, age-related changes in cognitive function among young adult: 1) siblings of individuals with schizophrenia (N = 66); (2) healthy control participants (N = 77); and (3) the siblings of healthy controls (N = 77). All subjects participated in a battery of tasks in four domains: 1) IQ; 2) working memory; 3) episodic memory; and 4) executive function. We found significant group differences in the relationships between age and performance in working memory and episodic memory, with similar patterns for executive function and verbal IQ. The siblings of individuals with schizophrenia showed impaired performance in working memory, episodic memory, and executive function. In addition, healthy controls and/or their siblings showed age-related improvements in all four cognitive domains, while the siblings of individuals with schizophrenia only showed this for verbal IQ. PMID:25485180

Altered cognitive development in the siblings of individuals with schizophrenia.

PubMed

Barch, Deanna M; Cohen, Rachel; Csernansky, John

2014-03-01

The goal of the current study was to further investigate the late neurodevelopmental hypothesis of schizophrenia by examining cross-sectional, age-related changes in cognitive function among young adult: 1) siblings of individuals with schizophrenia (N = 66); (2) healthy control participants (N = 77); and (3) the siblings of healthy controls (N = 77). All subjects participated in a battery of tasks in four domains: 1) IQ; 2) working memory; 3) episodic memory; and 4) executive function. We found significant group differences in the relationships between age and performance in working memory and episodic memory, with similar patterns for executive function and verbal IQ. The siblings of individuals with schizophrenia showed impaired performance in working memory, episodic memory, and executive function. In addition, healthy controls and/or their siblings showed age-related improvements in all four cognitive domains, while the siblings of individuals with schizophrenia only showed this for verbal IQ.

Spot the difference: Operational event sequence diagrams as a formal method for work allocation in the development of single-pilot operations for commercial aircraft.

PubMed

Harris, Don; Stanton, Neville A; Starr, Alison

2015-01-01

Function Allocation methods are important for the appropriate allocation of tasks between humans and automated systems. It is proposed that Operational Event Sequence Diagrams (OESDs) provide a simple yet rigorous basis upon which allocation of work can be assessed. This is illustrated with respect to a design concept for a passenger aircraft flown by just a single pilot where the objective is to replace or supplement functions normally undertaken by the second pilot with advanced automation. A scenario-based analysis (take off) was used in which there would normally be considerable demands and interactions with the second pilot. The OESD analyses indicate those tasks that would be suitable for allocation to automated assistance on the flight deck and those tasks that are now redundant in this new configuration (something that other formal Function Allocation approaches cannot identify). Furthermore, OESDs are demonstrated to be an easy to apply and flexible approach to the allocation of function in prospective systems. OESDs provide a simple yet rigorous basis upon which allocation of work can be assessed. The technique can deal with the flexible, dynamic allocation of work and the deletion of functions no longer required. This is illustrated using a novel design concept for a single-crew commercial aircraft.

Social cognition and prefrontal hemodynamic responses during a working memory task in schizophrenia.

PubMed

Pu, Shenghong; Nakagome, Kazuyuki; Yamada, Takeshi; Itakura, Masashi; Yamanashi, Takehiko; Yamada, Sayaka; Masai, Mieko; Miura, Akihiko; Yamauchi, Takahira; Satake, Takahiro; Iwata, Masaaki; Nagata, Izumi; Roberts, David L; Kaneko, Koichi

2016-03-01

Social cognition is an important determinant of functional impairment in schizophrenia, but its relationship with the prefrontal functional abnormalities associated with the condition is still unclear. The present study aimed to explore the relationship between social cognition and prefrontal function in patients with schizophrenia using 52-channel near-infrared spectroscopy (NIRS). Twenty-six patients with schizophrenia and 26 age-, gender-, and intelligence quotient-matched healthy controls (HCs) participated in the study. Hemodynamic responses in the prefrontal and superior temporal cortical regions were assessed during a working memory task using NIRS. Social cognition was assessed using the Social Cognition Screening Questionnaire (SCSQ). The observed hemodynamic responses were significantly reduced in the lateral prefrontal cortex (PFC), the frontopolar cortex, and temporal regions in subjects with schizophrenia compared to HCs. Additionally, lateral PFC hemodynamic responses assessed during the working memory task demonstrated a strong positive correlation with the SCSQ theory of mind (ToM) subscale score even after controlling for working memory performance. These results suggest that ToM integrity is closely related to lateral PFC functional abnormalities found in patients with schizophrenia. In addition, this study provides evidence to suggest that NIRS could be used to identify biomarkers of social cognition function in subjects with schizophrenia.

Work Function Engineering of Graphene

PubMed Central

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

Work Function Engineering of Graphene.

PubMed

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

2014-04-03

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.

Can psychosocial work conditions protect against age-related cognitive decline? Results from a systematic review.

PubMed

Nexø, Mette Andersen; Meng, Annette; Borg, Vilhelm

2016-07-01

According to the use it or lose it hypothesis, intellectually stimulating activities postpone age-related cognitive decline. A previous systematic review concluded that a high level of mental work demands and job control protected against cognitive decline. However, it did not distinguish between outcomes that were measured as cognitive function at one point in time or as cognitive decline. Our study aimed to systematically review which psychosocial working conditions were prospectively associated with high levels of cognitive function and/or changes in cognitive function over time. Articles were identified by a systematic literature search (MEDLINE, Web of Science (WOS), PsycNET, Occupational Safety and Health (OSH)). We included only studies with longitudinal designs examining the impact of psychosocial work conditions on outcomes defined as cognitive function or changes in cognitive function. Two independent reviewers compared title-abstract screenings, full-text screenings and quality assessment ratings. Eleven studies were included in the final synthesis and showed that high levels of mental work demands, occupational complexity or job control at one point in time were prospectively associated with higher levels of cognitive function in midlife or late life. However, the evidence to clarify whether these psychosocial factors also affected cognitive decline was insufficient, conflicting or weak. It remains speculative whether job control, job demands or occupational complexity can protect against cognitive decline. Future studies using methodological advancements can reveal whether workers gain more cognitive reserve in midlife and late life than the available evidence currently suggests. The public health implications of a previous review should thereby be redefined accordingly. 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/

Improving attention control in dysphoria through cognitive training: transfer effects on working memory capacity and filtering efficiency.

PubMed

Owens, Max; Koster, Ernst H W; Derakshan, Nazanin

2013-03-01

Impaired filtering of irrelevant information from working memory is thought to underlie reduced working memory capacity for relevant information in dysphoria. The current study investigated whether training-related gains in working memory performance on the adaptive dual n-back task could result in improved inhibitory function. Efficacy of training was monitored in a change detection paradigm allowing measurement of a sustained event-related potential asymmetry sensitive to working memory capacity and the efficient filtering of irrelevant information. Dysphoric participants in the training group showed training-related gains in working memory that were accompanied by gains in working memory capacity and filtering efficiency compared to an active control group. Results provide important initial evidence that behavioral performance and neural function in dysphoria can be improved by facilitating greater attentional control. Copyright © 2013 Society for Psychophysiological Research.

Genetic predictor of working memory and prefrontal function in women with HIV.

PubMed

Sundermann, Erin E; Bishop, Jeffrey R; Rubin, Leah H; Little, Deborah M; Meyer, Vanessa J; Martin, Eileen; Weber, Kathleen; Cohen, Mardge; Maki, Pauline M

2015-02-01

The Val158Met (rs4680) single-nucleotide polymorphism (SNP) of the catechol-O-methyltransferase gene (COMT) influences executive function and prefrontal function through its effect on dopamine (DA) metabolism. Both HIV and the Val allele of the Val158Met SNP are associated with compromised executive function and inefficient prefrontal function. The present study used behavioral and neuroimaging techniques to determine independent and interactive associations between HIV serostatus and COMT genotype on working memory and prefrontal function in women. For the behavioral study, 54 HIV-infected and 33 HIV-uninfected women completed the 0-, 1-, and 2-back conditions of the verbal N-back, a working memory test. For the imaging study, 36 women (23 HIV-infected, 13 HIV-uninfected) underwent functional magnetic resonance imaging (fMRI) assessments while completing the N-back task. HIV-infected women demonstrated significantly worse N-back performance compared with HIV-uninfected women (p < 0.05). A significant serostatus by genotype interaction (p < 0.01) revealed that, among Val/Val, but not Met allele carriers, HIV-infected women performed significantly worse than HIV-uninfected controls across N-back conditions (p < 0.01). Analogous to behavioral findings, a serostatus by genotype interaction revealed that HIV-infected Val/Val carriers showed significantly greater prefrontal activation compared with HIV-uninfected Val/Val carriers (p < 0.01). Conversely, HIV-uninfected Met allele carriers demonstrated significantly greater prefrontal activation compared with HIV-infected Met allele carriers. Findings suggest that the combination of HIV infection and the Val/Val COMT genotype leads to working memory deficits and altered prefrontal function in HIV-infected individuals.

Resting sympathetic arousal moderates the association between parasympathetic reactivity and working memory performance in adults reporting high levels of life stress.

PubMed

Giuliano, Ryan J; Gatzke-Kopp, Lisa M; Roos, Leslie E; Skowron, Elizabeth A

2017-08-01

The neurovisceral integration model stipulates that autonomic function plays a critical role in the regulation of higher-order cognitive processes, yet most work to date has examined parasympathetic function in isolation from sympathetic function. Furthermore, the majority of work has been conducted on normative samples, which typically demonstrate parasympathetic withdrawal to increase arousal needed to complete cognitive tasks. Little is known about how autonomic regulation supports cognitive function in populations exposed to high levels of stress, which is critical given that chronic stress exposure alters autonomic function. To address this, we sought to characterize how parasympathetic (high-frequency heart rate variability, HF-HRV) and sympathetic (preejection period, PEP) measures of cardiac function contribute to individual differences in working memory (WM) capacity in a sample of high-risk women. HF-HRV and PEP were measured at rest and during a visual change detection measure of WM. Multilevel modeling was used to examine within-person fluctuations in WM performance throughout the task concurrently with HF-HRV and PEP, as well as between-person differences as a function of resting HF-HRV and PEP levels. Results indicate that resting PEP moderated the association between HF-HRV reactivity and WM capacity. Increases in WM capacity across the task were associated with increases in parasympathetic activity, but only among individuals with longer resting PEP (lower sympathetic arousal). Follow-up analyses showed that shorter resting PEP was associated with greater cumulative risk exposure. These results support the autonomic space framework, in that the relationship between behavior and parasympathetic function appears dependent on resting sympathetic activation. © 2017 Society for Psychophysiological Research.

Resting sympathetic arousal moderates the association between parasympathetic reactivity and working memory performance in adults reporting high levels of life stress

PubMed Central

Giuliano, Ryan J.; Gatzke-Kopp, Lisa M.; Roos, Leslie E.; Skowron, Elizabeth A.

2017-01-01

The neurovisceral integration model stipulates that autonomic function plays a critical role in the regulation of higher-order cognitive processes, yet most work to date has examined parasympathetic function in isolation from sympathetic function. Furthermore, the majority of work has been conducted on normative samples, which typically demonstrate parasympathetic withdrawal to increase arousal needed to complete cognitive tasks. Little is known about how autonomic regulation supports cognitive function in populations exposed to high levels of stress, which is critical given that chronic stress exposure alters autonomic function. To address this, we sought to characterize how parasympathetic (high-frequency heart rate variability, HF-HRV) and sympathetic (preejection period, PEP) measures of cardiac function contribute to individual differences in working memory (WM) capacity in a sample of high-risk women. HF-HRV and PEP were measured at rest and during a visual change detection measure of WM. Multilevel modeling was used to examine within-person fluctuations in WM performance throughout the task concurrently with HF-HRV and PEP, as well as between-person differences as a function of resting HF-HRV and PEP levels. Results indicate that resting PEP moderated the association between HF-HRV reactivity and WM capacity. Increases in WM capacity across the task were associated with increases in parasympathetic activity, but only among individuals with longer resting PEP (lower sympathetic arousal). Follow-up analyses showed that shorter resting PEP was associated with greater cumulative risk exposure. These results support the autonomic space framework, in that the relationship between behavior and parasympathetic function appears dependent on resting sympathetic activation. PMID:28449242

The dopamine D2 receptor antagonist sulpiride modulates striatal BOLD signal during the manipulation of information in working memory.

PubMed

Dodds, Chris M; Clark, Luke; Dove, Anja; Regenthal, Ralf; Baumann, Frank; Bullmore, Ed; Robbins, Trevor W; Müller, Ulrich

2009-11-01

Dopamine (DA) plays an important role in working memory. However, the precise functions supported by different DA receptor subtypes in different neural regions remain unclear. The present study used pharmacological, event-related fMRI to test the hypothesis that striatal dopamine is important for the manipulation of information in working memory. Twenty healthy human subjects were scanned twice, once after placebo and once after sulpiride 400 mg, a selective DA D2 receptor antagonist, while performing a verbal working memory task requiring different levels of manipulation. Whilst there was no overall effect of sulpiride on task-dependent activation, individual variation in sulpiride plasma levels predicted the effect of working memory manipulation on activation in the putamen, suggesting a dose-dependent effect of DA antagonism on a striatally based manipulation process. These effects occurred in the context of a drug-induced improvement in performance on trials requiring the manipulation of information in working memory but not on simple retrieval trials. No significant drug effects were observed in the prefrontal cortex. These results support models of dopamine function that posit a 'gating' function for dopamine D2 receptors in the striatum, which enables the flexible updating and manipulation of information in working memory.

Effects of work stress and home stress on autonomic nervous function in Japanese male workers

PubMed Central

MAEDA, Eri; IWATA, Toyoto; MURATA, Katsuyuki

2014-01-01

Autonomic imbalance is one of the important pathways through which psychological stress contributes to cardiovascular diseases/sudden death. Although previous studies have focused mainly on stress at work (work stress), the association between autonomic function and stress at home (home stress) is still poorly understood. The purpose was to clarify the effect of work/home stress on autonomic function in 1,809 Japanese male workers. We measured corrected QT (QTc) interval and QT index on the electrocardiogram along with blood pressure and heart rate. Participants provided self-reported information about the presence/absence of work/home stress and the possible confounders affecting QT indicators. Home stress was related positively to QT index (p=0.040) after adjusting for the possible confounders, though work stress did not show a significant relation to QTc interval or QT index. The odds ratio of home stress to elevated QT index (≥105) was 2.677 (95% CI, 1.050 to 6.822). Work/home stress showed no significant relation to blood pressure or heart rate. These findings suggest that autonomic imbalance, readily assessed by QT indicators, can be induced by home stress in Japanese workers. Additional research is needed to identify different types of home stress that are strongly associated with autonomic imbalance. PMID:25382383

Effects of work stress and home stress on autonomic nervous function in Japanese male workers.

PubMed

Maeda, Eri; Iwata, Toyoto; Murata, Katsuyuki

2015-01-01

Autonomic imbalance is one of the important pathways through which psychological stress contributes to cardiovascular diseases/sudden death. Although previous studies have focused mainly on stress at work (work stress), the association between autonomic function and stress at home (home stress) is still poorly understood. The purpose was to clarify the effect of work/home stress on autonomic function in 1,809 Japanese male workers. We measured corrected QT (QTc) interval and QT index on the electrocardiogram along with blood pressure and heart rate. Participants provided self-reported information about the presence/absence of work/home stress and the possible confounders affecting QT indicators. Home stress was related positively to QT index (p=0.040) after adjusting for the possible confounders, though work stress did not show a significant relation to QTc interval or QT index. The odds ratio of home stress to elevated QT index (≥105) was 2.677 (95% CI, 1.050 to 6.822). Work/home stress showed no significant relation to blood pressure or heart rate. These findings suggest that autonomic imbalance, readily assessed by QT indicators, can be induced by home stress in Japanese workers. Additional research is needed to identify different types of home stress that are strongly associated with autonomic imbalance.

Do burned-out and work-engaged employees differ in the functioning of the hypothalamic-pituitary-adrenal axis?

PubMed

Langelaan, Saar; Bakker, Arnold B; Schaufeli, Wilmar B; van Rhenen, Willem; van Doornen, Lorenz J P

2006-10-01

The central aim of the present study was to examine differences in the functioning of the hypothalamic-pituitary-adrenal (HPA) axis between 29 burned-out, 33 work-engaged, and 26 healthy reference managers, as identified with the Maslach Burnout Inventory-General Survey and the Utrecht Work Engagement Scale. All of the managers were employed in a large Dutch telecommunications company. Salivary cortisol was sampled on three consecutive workdays and one nonworkday to determine the cortisol awakening response. Salivary dehydroepiandrosterone-sulfate (DHEAS), a cortisol counterbalancing product of the HPA axis, was measured on these days 1 hour after managers awakened. The dexamethasone suppression test was used to investigate the feedback sensitivity of the HPA axis. The morning cortisol levels were higher on the workdays than on the nonworkday, but this effect did not differ between the three groups. The burned-out, work-engaged, and reference groups did not differ in the cortisol and DHEAS levels, the slope of the cortisol awakening response, and the cortisol : DHEAS ratio. The work-engaged group showed a stronger cortisol suppression in response to the dexamethasone suppression test than the other two groups, the finding suggesting higher feedback sensitivity among work-engaged managers. Burned-out and work-engaged managers only differ marginally in HPA-axis functioning.

Oscillatory lower body negative pressure impairs working memory task-related functional hyperemia in healthy volunteers.

PubMed

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 cerebral blood flow produces causal reductions of memory task neurovascular coupling and memory task performance. Reductions of functional hyperemia are constrained by autoregulation. Copyright © 2017 the American Physiological Society.

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

PubMed

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.

Increased working memory related fMRI signal in children following Tick Borne Encephalitis.

PubMed

Henrik, Ullman; Åsa, Fowler; Ronny, Wickström

2016-01-01

Tick Borne Encephalitis (TBE) is a viral infection in the central nervous system endemic in Europe and Asia. While pediatric infection may carry a lower risk for serious neurological sequelae compared to adults, a large proportion of children experience long term cognitive problems, most markedly decreased working memory capacity. We explored whether task related functional magnetic resonance imaging (MRI) and diffusion tensor imaging (DTI) could reveal a biological correlate of status-post TBE in children. We examined 11 serologically verified pediatric TBE patients with central nervous system involvement with 55 healthy controls with working memory tests and MRI. The TBE patients showed a prominent deficit in working memory capacity and an increased task related functional MRI signal in working memory related cortical areas during a spatial working memory task performed without sedation. No diffusion differences could be found with DTI, in line with the reported paucity of anatomical abnormalities. This study is the first to demonstrate functional MRI abnormalities in TBE patients that bears similarity to other patient groups with diffuse neuronal damage. Copyright © 2015 European Paediatric Neurology Society. Published by Elsevier Ltd. All rights reserved.

[Ecological executive function characteristics and effects of executive function on social adaptive function in school-aged children with epilepsy].

PubMed

Xu, X J; Wang, L L; Zhou, N

2016-02-23

To explore the characteristics of ecological executive function in school-aged children with idiopathic or probably symptomatic epilepsy and examine the effects of executive function on social adaptive function. A total of 51 school-aged children with idiopathic or probably symptomatic epilepsy aged 5-12 years at our hospital and 37 normal ones of the same gender, age and educational level were included. The differences in ecological executive function and social adaptive function were compared between the two groups with the Behavior Rating Inventory of Executive Function (BRIEF) and Child Adaptive Behavior Scale, the Pearson's correlation test and multiple stepwise linear regression were used to explore the impact of executive function on social adaptive function. The scores of school-aged children with idiopathic or probably symptomatic epilepsy in global executive composite (GEC), behavioral regulation index (BRI) and metacognition index (MI) of BRIEF ((62±12), (58±13) and (63±12), respectively) were significantly higher than those of the control group ((47±7), (44±6) and (48±8), respectively))(P<0.01). The scores of school-aged children with idiopathic or probably symptomatic epilepsy in adaptive behavior quotient (ADQ), independence, cognition, self-control ((86±22), (32±17), (49±14), (41±16), respectively) were significantly lower than those of the control group ((120±12), (59±14), (59±7) and (68±10), respectively))(P<0.01). Pearson's correlation test showed that the scores of BRIEF, such as GEC, BRI, MI, inhibition, emotional control, monitoring, initiation and working memory had significantly negative correlations with the score of ADQ, independence, self-control ((r=-0.313--0.741, P<0.05)). Also, GEC, inhibition, MI, initiation, working memory, plan, organization and monitoring had significantly negative correlations with the score of cognition ((r=-0.335--0.437, P<0.05)); Multiple stepwise linear regression analysis showed that BRI, inhibition and working memory were closely related with the social adaptive function of school-aged children with idiopathic or probably symptomatic epilepsy. School-aged children with idiopathic or probably symptomatic epilepsy may have significantly ecological executive function impairment and social adaptive function reduction. The aspects of BRI, inhibition and working memory in ecological executive function are significantly related with social adaptive function in school-aged children with epilepsy.

Development of utility generic functional requirements for electronic work packages and computer-based procedures

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

Oxstrand, Johanna

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 usedmore » 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.« less

Assessing work disability for social security benefits: international models for the direct assessment of work capacity.

PubMed

Geiger, Ben Baumberg; Garthwaite, Kayleigh; Warren, Jon; Bambra, Clare

2017-08-25

It has been argued that social security disability assessments should directly assess claimants' work capacity, rather than relying on proxies such as on functioning. However, there is little academic discussion of how such assessments could be conducted. The article presents an account of different models of direct disability assessments based on case studies of the Netherlands, Germany, Denmark, Norway, the United States of America, Canada, Australia, and New Zealand, utilising over 150 documents and 40 expert interviews. Three models of direct work disability assessments can be observed: (i) structured assessment, which measures the functional demands of jobs across the national economy and compares these to claimants' functional capacities; (ii) demonstrated assessment, which looks at claimants' actual experiences in the labour market and infers a lack of work capacity from the failure of a concerned rehabilitation attempt; and (iii) expert assessment, based on the judgement of skilled professionals. Direct disability assessment within social security is not just theoretically desirable, but can be implemented in practice. We have shown that there are three distinct ways that this can be done, each with different strengths and weaknesses. Further research is needed to clarify the costs, validity/legitimacy, and consequences of these different models. Implications for rehabilitation It has recently been argued that social security disability assessments should directly assess work capacity rather than simply assessing functioning - but we have no understanding about how this can be done in practice. Based on case studies of nine countries, we show that direct disability assessment can be implemented, and argue that there are three different ways of doing it. These are "demonstrated assessment" (using claimants' experiences in the labour market), "structured assessment" (matching functional requirements to workplace demands), and "expert assessment" (the judgement of skilled professionals). While it is possible to implement a direct assessment of work capacity for social security benefits, further research is necessary to understand how best to maximise validity, legitimacy, and cost-effectiveness.

Speech Recognition in Adults with Cochlear Implants: The Effects of Working Memory, Phonological Sensitivity, and Aging

ERIC Educational Resources Information Center

Moberly, Aaron C.; Harris, Michael S.; Boyce, Lauren; Nittrouer, Susan

2017-01-01

Purpose: Models of speech recognition suggest that "top-down" linguistic and cognitive functions, such as use of phonotactic constraints and working memory, facilitate recognition under conditions of degradation, such as in noise. The question addressed in this study was what happens to these functions when a listener who has experienced…

Functional Developmental Similarities and Differences in the Neural Correlates of Verbal and Nonverbal Working Memory Tasks

ERIC Educational Resources Information Center

Brahmbhatt, Shefali B.; McAuley, Tara; Barch, Deanna M.

2008-01-01

Relatively little is known about the functional development of verbal and nonverbal working memory during adolescence. Behavioral studies have demonstrated that WM capacity increases with age, yet relatively few studies have assessed the relationship between brain-activity and age-related changes in WM capacity, especially as it differs across…

Intellectual Growth in Children as a Function of Domain Specific and Domain General Working Memory Subgroups

ERIC Educational Resources Information Center

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…

Work function measurements by the field emission retarding potential method

NASA Technical Reports Server (NTRS)

Swanson, L. W.; Strayer, R. W.; Mackie, W. A.

1971-01-01

Using the field emission retarding potential method true work functions have been measured for the following monocrystalline substrates: W(110), W(111), W(100), Nb(100), Ni(100), Cu(100), Ir(110) and Ir(111). The electron elastic and inelastic reflection coefficients from several of these surfaces have also been examined near zero primary beam energy.

Probe-Hole Field Emission Microscope System Controlled by Computer

NASA Astrophysics Data System (ADS)

Gong, Yunming; Zeng, Haishan

1991-09-01

A probe-hole field emission microscope system, controlled by an Apple II computer, has been developed and operated successfully for measuring the work function of a single crystal plane. The work functions on the clean W(100) and W(111) planes are measured to be 4.67 eV and 4.45 eV, respectively.

The Effect of Non-Visual Working Memory Load on Top-Down Modulation of Visual Processing

ERIC Educational Resources Information Center

Rissman, Jesse; Gazzaley, Adam; D'Esposito, Mark

2009-01-01

While a core function of the working memory (WM) system is the active maintenance of behaviorally relevant sensory representations, it is also critical that distracting stimuli are appropriately ignored. We used functional magnetic resonance imaging to examine the role of domain-general WM resources in the top-down attentional modulation of…

ADHD and Working Memory: The Impact of Central Executive Deficits and Exceeding Storage/Rehearsal Capacity on Observed Inattentive Behavior

ERIC Educational Resources Information Center

Kofler, Michael J.; Rapport, Mark D.; Bolden, Jennifer; Sarver, Dustin E.; Raiker, Joseph S.

2010-01-01

Inattentive behavior is considered a core and pervasive feature of ADHD; however, an alternative model challenges this premise and hypothesizes a functional relationship between working memory deficits and inattentive behavior. The current study investigated whether inattentive behavior in children with ADHD is functionally related to the…

An Updated Typology of Causative Constructions: Form-Function Mappings in Hupa (California Athabaskan), Chungli Ao (Tibeto-Burman) and Beyond

ERIC Educational Resources Information Center

Escamilla, Ramon Matthew, Jr.

2012-01-01

Taking up analytical issues raised primarily in Dixon (2000) and Dixon & Aikhenvald (2000), this dissertation combines descriptive work with a medium-sized (50-language) typological study. Chapter 1 situates the dissertation against a concise survey of typological-functional work on causative constructions from the last few decades, and…

Work function measurements of copper nanoparticle intercalated polyaniline nanocomposite thin films

NASA Astrophysics Data System (ADS)

Patil, U. V.; Ramgir, Niranjan S.; Bhogale, A.; Debnath, A. K.; Muthe, K. P.; Gadkari, S. C.; Kothari, D. C.

2017-05-01

The nature of contact between the electrode and the sensing material plays a crucial role in governing the sensing mechanism. Thin films of polyaniline (PANI) and copper-polyaniline nanocomposite (NC) have been deposited at room temperatures by in-situ oxidative polymerization of aniline in the presence of Cu nanoparticles. For sensing applications a thin film Au (gold) ˜100 nm is deposited and used as a conducting electrode. To understand the nature of contact (i.e., ohmic or Schottky) the work function of the conducting polyaniline and nanocomposite films were measured using Kelvin Probe method. I-V characteristics of PANI and NC films investigated at room temperatures further corroborates and confirms the formation of Ohmic contact as evident from work function measurements.

Associations among false belief understanding, counterfactual reasoning, and executive function.

PubMed

Guajardo, Nicole R; Parker, Jessica; Turley-Ames, Kandi

2009-09-01

The primary purposes of the present study were to clarify previous work on the association between counterfactual thinking and false belief performance to determine (1) whether these two variables are related and (2) if so, whether executive function skills mediate the relationship. A total of 92 3-, 4-, and 5-year-olds completed false belief, counterfactual, working memory, representational flexibility, and language measures. Counterfactual reasoning accounted for limited unique variance in false belief. Both working memory and representational flexibility partially mediated the relationship between counterfactual and false belief. Children, like adults, also generated various types of counterfactual statements to differing degrees. Results demonstrated the importance of language and executive function for both counterfactual and false belief. Implications are discussed.

Schottky barrier amorphous silicon solar cell with thin doped region adjacent metal Schottky barrier

DOEpatents

Carlson, David E.; Wronski, Christopher R.

1979-01-01

A Schottky barrier amorphous silicon solar cell incorporating a thin highly doped p-type region of hydrogenated amorphous silicon disposed between a Schottky barrier high work function metal and the intrinsic region of hydrogenated amorphous silicon wherein said high work function metal and said thin highly doped p-type region forms a surface barrier junction with the intrinsic amorphous silicon layer. The thickness and concentration of p-type dopants in said p-type region are selected so that said p-type region is fully ionized by the Schottky barrier high work function metal. The thin highly doped p-type region has been found to increase the open circuit voltage and current of the photovoltaic device.

The Profile of Memory Function in Children With Autism

PubMed Central

Williams, Diane L.; Goldstein, Gerald; Minshew, Nancy J.

2007-01-01

A clinical memory test was administered to 38 high-functioning children with autism and 38 individually matched normal controls, 8–16 years of age. The resulting profile of memory abilities in the children with autism was characterized by relatively poor memory for complex visual and verbal information and spatial working memory with relatively intact associative learning ability, verbal working memory, and recognition memory. A stepwise discriminant function analysis of the subtests found that the Finger Windows subtest, a measure of spatial working memory, discriminated most accurately between the autism and normal control groups. A principal components analysis indicated that the factor structure of the subtests differed substantially between the children with autism and controls, suggesting differing organizations of memory ability. PMID:16460219

Color and psychological functioning: a review of theoretical and empirical work

PubMed Central

Elliot, Andrew J.

2015-01-01

In the past decade there has been increased interest in research on color and psychological functioning. Important advances have been made in theoretical work and empirical work, but there are also important weaknesses in both areas that must be addressed for the literature to continue to develop apace. In this article, I provide brief theoretical and empirical reviews of research in this area, in each instance beginning with a historical background and recent advancements, and proceeding to an evaluation focused on weaknesses that provide guidelines for future research. I conclude by reiterating that the literature on color and psychological functioning is at a nascent stage of development, and by recommending patience and prudence regarding conclusions about theory, findings, and real-world application. PMID:25883578

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

Yoshitake, Michiko, E-mail: yoshitake.michiko@nims.go.jp

Transition-metal carbides and nitrides (TMCs and TMNs) are promising electrode materials for various electronic devices such as metal-oxide-semiconductor field-effect transistors and metal-insulator-metal capacitors. In this paper, the work functions of TMCs and TMNs are discussed systematically. Based upon the origin of the work function, the effect upon transition metal species by different periodic table groups is explained, carbides are compared with nitrides for the same transition metal, and the effect of carbon or nitrogen vacancies is discussed. In addition, a method to estimate the generic trend of the work function is proposed for TMC{sub x}, TMN{sub x}, TMC{sub 1−y}N{sub y}more » (transition metal carbonitrides), and TM{sub 1−z}TM′{sub z}C (alloy carbides)« less

Spatial Working Memory Ability in Individuals at Ultra High Risk for Psychosis

PubMed Central

Goghari, Vina M.; Brett, Caroline; Tabraham, Paul; Johns, Louise; Valmaggia, Lucia; Broome, Matthew; Woolley, James; Bramon, Elvira; Howes, Oliver

2014-01-01

The goal of this investigation was to clarify the nature of spatial working memory difficulties in individuals at ultra high risk (UHR) for psychosis. We evaluated spatial working memory and intelligence in 96 individuals at UHR for psychosis, 28 patients with first episode psychosis (FEP), and 23 healthy controls. Fourteen UHR individuals developed a psychotic disorder during follow-up. Compared to controls, the UHR group was impaired in both the short-term maintenance of material and in the effective use of strategy, but not more immediate memory. These impairments were not as severe as those in the FEP group, as the UHR group performed better than the FEP group. A similar pattern of results was found for the intelligence measures. Discriminant function analyses demonstrated short-term maintenance of material significantly differentiated the UHR and healthy control groups even when accounting for full scale intelligence quotient (IQ); whereas full scale IQ significantly differentiated the UHR and FEP groups and FEP and control groups. Notably, within the UHR group, impaired spatial working memory performance was associated with lower global functioning, but not full scale IQ. The subgroup of UHR individuals who later developed psychosis was not significantly more impaired on any aspect of working memory performance than the group of UHR individuals who did not develop psychosis. Given, the relationship between spatial working memory deficits and functional outcome, these results indicate that cognitive remediation could be useful in individuals at UHR for psychosis to potentially improve functioning. PMID:24398256

Interventions to improve executive functioning and working memory in school-aged children with AD(H)D: a randomised controlled trial and stepped-care approach.

PubMed

van der Donk, Marthe L A; Hiemstra-Beernink, Anne-Claire; Tjeenk-Kalff, Ariane C; van der Leij, Aryan V; Lindauer, Ramón J L

2013-01-11

Deficits in executive functioning are of great significance in attention-deficit/hyperactivity disorder (ADHD). One of these executive functions, working memory, plays an important role in academic performance and is often seen as the core deficit of this disorder. There are indications that working memory problems and academic performance can be improved by school-oriented interventions but this has not yet been studied systematically. In this study we will determine the short- and long-term effects of a working memory--and an executive function training applied in a school situation for children with AD(H)D, taking individual characteristics, the level of impairment and costs (stepped-care approach) into account. The study consists of two parts: the first part is a randomised controlled trial with school-aged children (8-12 yrs) with AD(H)D. Two groups (each n = 50) will be randomly assigned to a well studied computerized working memory training 'Cogmed', or to the 'Paying attention in class' intervention which is an experimental school-based executive function training. Children will be selected from regular -and special education primary schools in the region of Amsterdam, the Netherlands. The second part of the study will determine which specific characteristics are related to non-response of the 'Paying attention in class' intervention. School-aged children (8-12 yrs) with AD(H)D will follow the experimental school-based executive function training 'Paying attention in class' (n = 175). Academic performance and neurocognitive functioning (primary outcomes) are assessed before, directly after and 6 months after training. Secondary outcome measures are: behaviour in class, behaviour problems and quality of life. So far, there is limited but promising evidence that working memory - and other executive function interventions can improve academic performance. Little is know about the applicability and generalization effects of these interventions in a classroom situation. This study will contribute to this lack of information, especially information related to real classroom and academic situations. By taking into account the costs of both interventions, level of impairment and individual characteristics of the child (stepped-care approach) we will be able to address treatment more adequately for each individual in the future. Nederlands Trial Register NTR3415.

Sex Differences in Working Memory after Mild Traumatic Brain Injury: A Functional MR Imaging Study.

PubMed

Hsu, Hui-Ling; Chen, David Yen-Ting; Tseng, Ying-Chi; Kuo, Ying-Sheng; Huang, Yen-Lin; Chiu, Wen-Ta; Yan, Feng-Xian; Wang, Wei-Shuan; Chen, Chi-Jen

2015-09-01

To evaluate sex differences in mild traumatic brain injury (MTBI) with working memory functional magnetic resonance (MR) imaging. Research ethics committee approval and patient written informed consent were obtained. Working memory brain activation patterns were assessed with functional MR imaging in 30 patients (15 consecutive men and 15 consecutive women) with MTBI and 30 control subjects (15 consecutive men and 15 consecutive women). Two imaging studies were performed in patients: the initial study, which was performed within 1 month after the injury, and a follow-up study, which was performed 6 weeks after the first study. For each participant, digit span and continuous performance testing were performed before functional MR imaging. Clinical data were analyzed by using Kruskal-Wallis, Mann-Whitney U, Wilcoxon signed rank, and Fisher exact tests. Within- and between-group differences of functional MR imaging data were analyzed with one- and two-sample t tests, respectively. Among female participants, the total digit span score was lower in the MTBI group than in the control group (P = .044). In initial working memory functional MR imaging studies, hyperactivation was found in the male MTBI group and hypoactivation was found in the female MTBI group compared with control male and female groups, respectively. At the 6-week follow-up study, the female MTBI group showed persistent hypoactivation, whereas the male MTBI group showed a regression of hyperactivation at visual comparison of activation maps. The male MTBI group was also found to have a higher initial ß value than the male control group (P = .040), and there was no significant difference between the male MTBI group and the male control group (P = .221) at follow-up evaluation, which was comparable to findings on activation maps. In the female MTBI group, average ß values at both initial and follow-up studies were lower compared with those in the female control group but were not statistically significant (P = .663 and P = .191, respectively). Female patients with MTBI had lower digit span scores than did female control subjects, and functional MR imaging depicted sex differences in working memory functional activation; hypoactivation with nonrecovery of activation change at follow-up studies may suggest a worse working memory outcome in female patients with MTBI.

Illness consequences after myocardial infarction: problems with physical functioning and return to work.

PubMed

Brink, Eva; Brändström, Yvonne; Cliffordsson, Christina; Herlitz, Johan; Karlson, Björn W

2008-12-01

This paper is a report of a study to explore health problems, physical and mental functioning, and physical activity in working-age patients after myocardial infarction, in order to assess the possible effects of these factors on return to work. A diagnosis of myocardial infarction may discourage patients from continuing an active working life. Enabling myocardial infarction patients to return to work has benefits for both individuals and society. A convenience sample was recruited of 88 patients,

Working memory deficits in high-functioning adolescents with autism spectrum disorders: neuropsychological and neuroimaging correlates.

PubMed

Barendse, Evelien M; Hendriks, Marc Ph; Jansen, Jacobus Fa; Backes, Walter H; Hofman, Paul Am; Thoonen, Geert; Kessels, Roy Pc; Aldenkamp, Albert P

2013-06-04

Working memory is a temporary storage system under attentional control. It is believed to play a central role in online processing of complex cognitive information and may also play a role in social cognition and interpersonal interactions. Adolescents with a disorder on the autism spectrum display problems in precisely these domains. Social impairments, communication difficulties, and repetitive interests and activities are core domains of autism spectrum disorders (ASD), and executive function problems are often seen throughout the spectrum. As the main cognitive theories of ASD, including the theory of mind deficit hypotheses, weak central coherence account, and the executive dysfunction theory, still fail to explain the broad spectrum of symptoms, a new perspective on the etiology of ASD is needed. Deficits in working memory are central to many theories of psychopathology, and are generally linked to frontal-lobe dysfunction. This article will review neuropsychological and (functional) brain imaging studies on working memory in adolescents with ASD. Although still disputed, it is concluded that within the working memory system specific problems of spatial working memory are often seen in adolescents with ASD. These problems increase when information is more complex and greater demands on working memory are made. Neuroimaging studies indicate a more global working memory processing or connectivity deficiency, rather than a focused deficit in the prefrontal cortex. More research is needed to relate these working memory difficulties and neuroimaging results in ASD to the behavioral difficulties as seen in individuals with a disorder on the autism spectrum.

Work experiences among attendees of day centres for people with psychiatric disabilities.

PubMed

Eklund, Mona; Sandlund, Mikael

2015-01-01

It is possible that people with psychiatric disabilities who visit day centres have previous work experiences that may be seen as resources for their current engagement in day centre activities. Research in this respect seems to lack, however. To investigate work experiences among attendees at day centres for people with psychiatric disabilities and relationships with current type of day centre (work-oriented, meeting place-oriented or mixed), engagement in day centre activities, motivation and socio-demographic and health-related factors. Seventy-seven attendees responded to questionnaires. Global Assessment of Functioning, GAF, was also used. Work was categorised into Group I (professionals, semi-professionals), Group II (clerical support, services workers) and Group III (e.g. craft workers, elementary occupations). Almost everyone had previously had open-market employment; more than half for ≥ 10 years. Group I was more common in mixed centres, Group II in meeting place-oriented ones and Group III in work-oriented ones. Group I more frequently had college degree and was rated high on GAF functioning. Women were over-represented in Group II, and men in Group III and in meeting place-oriented centres. Attending mixed centres was more likely when having a college degree, scoring high on GAF functioning and being highly engaged in activities. Attendees at work-oriented day centres were characterised by being motivated for spending time alone and reporting a diagnosis of psychosis. The participants had unused working capacity. No clear-cut relationships were found between work experiences and the investigated correlates.

Facilitating the Genesis of Functional Working Spaces in Guided Explorations

ERIC Educational Resources Information Center

Miranda, Vicente Carrión; Pluvinage, François; Adjiage, Robert

2016-01-01

Approximating given real-valued functions by affine functions is among the most basic activities with functions. In this study we examine two contexts in which two such approximations are performed. The first involves a microscopic representation of functions for the study of tangents; the second a macroscopic representation of functions for the…

Exposure to Blue Light Increases Subsequent Functional Activation of the Prefrontal Cortex During Performance of a Working Memory Task

PubMed Central

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.

2016-01-01

Study Objectives: 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. Methods: 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). Results: 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. Conclusions: 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. Citation: Alkozei A, Smith R, Pisner DA, Vanuk JR, Berryhill SM, Fridman A, Shane BR, Knight SA, Killgore WD. Exposure to blue light increases subsequent functional activation of the prefrontal cortex during performance of a working memory task. SLEEP 2016;39(9):1671–1680. PMID:27253770

Cultural and Intellectual Openness Differentially Relate to Social Judgments of Potential Work Partners.

PubMed

Porter, Caitlin M; Parrigon, Scott E; Woo, Sang Eun; Saef, Rachel M; Tay, Louis

2017-10-01

This study investigates the differential functioning of cultural and intellectual openness (the two aspects of Openness to Experience) in relation to social cognitive processes by examining how they influence people's perceptions and interpretations of social information when deciding to initiate working relationships. Using a policy-capturing design, 681 adult participants were asked to rate their similarity to and preference to work with potential work partners characterized by varying nationalities and levels of work-related competence. Multilevel moderated mediation was conducted to simultaneously evaluate whether the indirect effects of potential work partners' characteristics (i.e., nationalities and levels of work-related competence) on work partner preference through perceived similarity were moderated by cultural and intellectual openness. Perceived similarity mediated the relationships between work partner nationality and work-related competence and participants' work partner preferences. Furthermore, the negative indirect effect of work partner nationality on work partner preference via perceived similarity was attenuated by cultural openness, and the positive indirect effect of work partner work-related competence on work partner preference via perceived similarity was strengthened by intellectual openness. Cultural and intellectual openness may have distinct functions that influence how people perceive, evaluate, and appreciate social information when making social judgments. © 2016 Wiley Periodicals, Inc.

Thoughts on the Professionalization and Industrialization of Social Work in China

ERIC Educational Resources Information Center

Feng, Cui

2013-01-01

China's economic and social development requires professional social work. To achieve the professionalization of social work in China, we must focus on its indigenization, change the function of mass organizations, and improve the professional quality of existing social work personnel. We must also pay attention to promoting social work theory and…

20 CFR 404.1560 - When we will consider your vocational background.

Code of Federal Regulations, 2010 CFR

2010-04-01

... section. (b) Past relevant work. We will first compare our assessment of your residual functional capacity with the physical and mental demands of your past relevant work. (1) Definition of past relevant work. Past relevant work is work that you have done within the past 15 years, that was substantial gainful...

Orienting the Work-Based Curriculum Towards Work Process Knowledge: A Rationale and a German Case Study

ERIC Educational Resources Information Center

Boreham, Nick

2004-01-01

The term 'work process knowledge' refers to the knowledge needed for working in flexible and innovative business environments, including those in which information and communication technologies have been introduced to integrate previously separated production functions. It involves a systems-level understanding of the work process in the…

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

PubMed

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.

The Dopamine D5 Receptor Is Involved in Working Memory

PubMed Central

Carr, Gregory V.; Maltese, Federica; Sibley, David R.; Weinberger, Daniel R.; Papaleo, Francesco

2017-01-01

Pharmacological studies indicate that dopamine D1-like receptors (D1 and D5) are critically involved in cognitive function. However, the lack of pharmacological ligands selective for either the D1 or D5 receptors has made it difficult to determine the unique contributions of the D1-like family members. To circumvent these pharmacological limitations, we used D5 receptor homozygous (-/-) and heterozygous (+/-) knockout mice, to identify the specific role of this receptor in higher order cognitive functions. We identified a novel role for D5 receptors in the regulation of spatial working memory and temporal order memory function. The D5 mutant mice acquired a discrete paired-trial variable-delay T-maze task at normal rates. However, both D5+/- and D5-/- mice exhibited impaired performance compared to D5+/+ littermates when a higher burden on working memory faculties was imposed. In a temporal order object recognition task, D5+/- exhibited significant memory deficits. No D5-dependent differences in locomotor functions and interest in exploring objects were evident. Molecular biomarkers of dopaminergic functions within the prefrontal cortex (PFC) revealed a selective gene-dose effect on Akt phosphorylation at Ser473 with increased levels in D5-/- knockout mice. A trend toward reduced levels in CaMKKbeta brain-specific band (64 kDa) in D5-/- compared to D5+/+ was also evident. These findings highlight a previously unidentified role for D5 receptors in working memory function and associated molecular signatures within the PFC. PMID:29056909

Factors promoting sustainable work in women with fibromyalgia.

PubMed

Palstam, Annie; Gard, Gunvor; Mannerkorpi, Kaisa

2013-09-01

To examine and describe the factors promoting sustainable work in women with fibromyalgia (FM). A qualitative interview study. Twenty-seven gainfully employed women with FM participated in five focus group interviews. Their median age was 52 years, ranging from 33 to 62. The interviews were recorded, transcribed verbatim and analysed by qualitative latent content analysis. Four categories were identified describing factors promoting sustainable work: the meaning of work and individual strategies were individual promoters while a favourable work environment and social support outside work were environmental promoters. The meaning of work included individual meaning and social meaning. The individual strategies included handling symptoms, the work day and long-term work life. A favourable work environment included the physical and psychosocial work environment. Social support outside work included societal and private social supports. Promoting factors for work were identified, involving individual and environmental factors. These working women with FM had developed advanced well-functioning strategies to enhance their work ability. The development of such strategies should be supported by health-care professionals as well as employers to promote sustainable work in women with FM. Work disability is a common consequence of fibromyalgia (FM). Working women with FM appear to have developed advanced well-functioning individual strategies to enhance their work ability. The development of individual strategies should be supported by health-care professionals as well as employers to promote sustainable work and health in women with FM.

The Acceptability and Potential Utility of Cognitive Training to Improve Working Memory in Persons Living With HIV: A Preliminary Randomized Trial.

PubMed

Towe, Sheri L; Patel, Puja; Meade, Christina S

HIV-associated neurocognitive impairments that impact daily function persist in the era of effective antiretroviral therapy. Cognitive training, a promising low-cost intervention, has been shown to improve neurocognitive functioning in some clinical populations. We tested the feasibility, acceptability, and preliminary effects of computerized cognitive training to improve working memory in persons living with HIV infection (PLWH) and working memory impairment. In this randomized clinical trial, we assigned 21 adult PLWH to either an experimental cognitive training intervention or an attention-matched control training intervention. Participants completed 12 training sessions across 10 weeks with assessments at baseline and post-training. Session attendance was excellent and participants rated the program positively. Participants in the experimental arm demonstrated improved working memory function over time; participants in the control arm showed no change. Our results suggest that cognitive training may be a promising intervention for working memory impairment in PLWH and should be evaluated further. Copyright © 2017 Association of Nurses in AIDS Care. Published by Elsevier Inc. All rights reserved.

Acute pulmonary function change associated with work on large dairies in California.

PubMed

Eastman, Chelsea; Schenker, Marc B; Mitchell, Diane C; Tancredi, Daniel J; Bennett, Deborah H; Mitloehner, Frank M

2013-01-01

To study whether dairy workers in California have lower baseline and greater cross-shift decrements in lung function than control employees. A cross-sectional study of 210 dairy and 47 control workers who completed questionnaires and spirometry before and after the work shift. Dairy work was associated with mean baseline differences of -0.132 L (P = 0.07) and -0.131 L (P = 0.13) in forced expiratory volume in 1 second and forced vital capacity, respectively, compared with control employees, adjusting for age, height, smoking status, and days back at work since last day off. Dairy work was associated with a mean cross-shift difference of -65.2 mL (P = 0.02) and -103.1 mL (P < 0.01) in forced expiratory volume in 1 second and forced vital capacity, respectively, adjusting for smoking status and work-shift time. Dairy work in California was associated with mild acute airway obstruction. The unclear long-term effect of dairy work in California merits further investigation.

Selective updating of working memory content modulates meso-cortico-striatal activity.

PubMed

Murty, Vishnu P; Sambataro, Fabio; Radulescu, Eugenia; Altamura, Mario; Iudicello, Jennifer; Zoltick, Bradley; Weinberger, Daniel R; Goldberg, Terry E; Mattay, Venkata S

2011-08-01

Accumulating evidence from non-human primates and computational modeling suggests that dopaminergic signals arising from the midbrain (substantia nigra/ventral tegmental area) mediate striatal gating of the prefrontal cortex during the selective updating of working memory. Using event-related functional magnetic resonance imaging, we explored the neural mechanisms underlying the selective updating of information stored in working memory. Participants were scanned during a novel working memory task that parses the neurophysiology underlying working memory maintenance, overwriting, and selective updating. Analyses revealed a functionally coupled network consisting of a midbrain region encompassing the substantia nigra/ventral tegmental area, caudate, and dorsolateral prefrontal cortex that was selectively engaged during working memory updating compared to the overwriting and maintenance of working memory content. Further analysis revealed differential midbrain-dorsolateral prefrontal interactions during selective updating between low-performing and high-performing individuals. These findings highlight the role of this meso-cortico-striatal circuitry during the selective updating of working memory in humans, which complements previous research in behavioral neuroscience and computational modeling. Published by Elsevier Inc.

Effects of selective serotonin reuptake and dual serotonergic-noradrenergic reuptake treatments on attention and executive functions in patients with major depressive disorder.

PubMed

Herrera-Guzmán, Ixchel; Herrera-Abarca, Jorge E; Gudayol-Ferré, Esteve; Herrera-Guzmán, Daniel; Gómez-Carbajal, Lizbeth; Peña-Olvira, Miriam; Villuendas-González, Erwin; Joan, Guàrdia-Olmos

2010-05-30

Several reports suggest that antidepressants may improve cognitive functioning in patients with major depressive disorder (MDD). The present work aims to study the effects of selective serotonin reuptake inhibitors (SSRIs) and serotonergic-noradrenergic reuptake inhibitors (SNRIs) treatments on the performance of working memory, attention and executive functions in patients with MDD. A total of 73 subjects meeting the Diagnostic and Statistical Manual of Mental Disorders version IV (DSM-IV) criteria for MDD, and 37 control subjects were assessed with the Hamilton Depression Rating Scale and a neuropsychological battery. The subjects were medicated with escitalopram (n=36) or duloxetine (n=37) for 24 weeks. At the end of the trial, the subjects were assessed again with the same tests. The depressed subjects showed alterations in attention and cognitive functions when compared to the control group. The administration of both treatments improved working memory, as well as attention and all the executive functions, but the cognitive functions of depressed patients do not improve enough to reach the levels of performance of the control subjects. Our results suggest that both SSRI and SNRI treatments presented the same efficacy in improving attention and the remaining executive functions. Copyright 2010 Elsevier Ireland Ltd. All rights reserved.

More on boundary holographic Witten diagrams

NASA Astrophysics Data System (ADS)

Sato, Yoshiki

2018-01-01

In this paper we discuss geodesic Witten diagrams in general holographic conformal field theories with boundary or defect. In boundary or defect conformal field theory, two-point functions are nontrivial and can be decomposed into conformal blocks in two distinct ways; ambient channel decomposition and boundary channel decomposition. In our previous work [A. Karch and Y. Sato, J. High Energy Phys. 09 (2017) 121., 10.1007/JHEP09(2017)121] we only consider two-point functions of same operators. We generalize our previous work to a situation where operators in two-point functions are different. We obtain two distinct decomposition for two-point functions of different operators.

Employee subjective well-being and physiological functioning: An integrative model

PubMed Central

Tay, Louis

2015-01-01

Research shows that worker subjective well-being influences physiological functioning—an early signal of poor health outcomes. While several theoretical perspectives provide insights on this relationship, the literature lacks an integrative framework explaining the relationship. We develop a conceptual model explaining the link between subjective well-being and physiological functioning in the context of work. Integrating positive psychology and occupational stress perspectives, our model explains the relationship between subjective well-being and physiological functioning as a result of the direct influence of subjective well-being on physiological functioning and of their common relationships with work stress and personal resources, both of which are influenced by job conditions. PMID:28070359

MODY - calculation of ordered structures by symmetry-adapted functions

NASA Astrophysics Data System (ADS)

Białas, Franciszek; Pytlik, Lucjan; Sikora, Wiesława

2016-01-01

In this paper we focus on the new version of computer program MODY for calculations of symmetryadapted functions based on the theory of groups and representations. The choice of such a functional frame of coordinates for description of ordered structures leads to a minimal number of parameters which must be used for presentation of such structures and investigations of their properties. The aim of this work is to find those parameters, which are coefficients of a linear combination of calculated functions, leading to construction of different types of structure ordering with a given symmetry. A spreadsheet script for simplification of this work has been created and attached to the program.

Graphene-based room-temperature implementation of a modified Deutsch-Jozsa quantum algorithm.

PubMed

Dragoman, Daniela; Dragoman, Mircea

2015-12-04

We present an implementation of a one-qubit and two-qubit modified Deutsch-Jozsa quantum algorithm based on graphene ballistic devices working at room temperature. The modified Deutsch-Jozsa algorithm decides whether a function, equivalent to the effect of an energy potential distribution on the wave function of ballistic charge carriers, is constant or not, without measuring the output wave function. The function need not be Boolean. Simulations confirm that the algorithm works properly, opening the way toward quantum computing at room temperature based on the same clean-room technologies as those used for fabrication of very-large-scale integrated circuits.

Independence of Hot and Cold Executive Function Deficits in High-Functioning Adults with Autism Spectrum Disorder.

PubMed

Zimmerman, David L; Ownsworth, Tamara; O'Donovan, Analise; Roberts, Jacqueline; Gullo, Matthew J

2016-01-01

Individuals with autistic spectrum disorder (ASD) display diverse deficits in social, cognitive and behavioral functioning. To date, there has been mixed findings on the profile of executive function deficits for high-functioning adults (IQ > 70) with ASD. A conceptual distinction is commonly made between "cold" and "hot" executive functions. Cold executive functions refer to mechanistic higher-order cognitive operations (e.g., working memory), whereas hot executive functions entail cognitive abilities supported by emotional awareness and social perception (e.g., social cognition). This study aimed to determine the independence of deficits in hot and cold executive functions for high-functioning adults with ASD. Forty-two adults with ASD (64% male, aged 18-66 years) and 40 age and gender matched controls were administered The Awareness of Social Inference Test (TASIT; emotion recognition and social inference), Letter Number Sequencing (working memory) and Hayling Sentence Completion Test (response initiation and suppression). Between-group analyses identified that the ASD group performed significantly worse than matched controls on all measures of cold and hot executive functions (d = 0.54 - 1.5). Hierarchical multiple regression analyses revealed that the ASD sample performed more poorly on emotion recognition and social inference tasks than matched controls after controlling for cold executive functions and employment status. The findings also indicated that the ability to recognize emotions and make social inferences was supported by working memory and response initiation and suppression processes. Overall, this study supports the distinction between hot and cold executive function impairments for adults with ASD. Moreover, it advances understanding of higher-order impairments underlying social interaction difficulties for this population which, in turn, may assist with diagnosis and inform intervention programs.

Independence of Hot and Cold Executive Function Deficits in High-Functioning Adults with Autism Spectrum Disorder

PubMed Central

Zimmerman, David L.; Ownsworth, Tamara; O'Donovan, Analise; Roberts, Jacqueline; Gullo, Matthew J.

2016-01-01

Individuals with autistic spectrum disorder (ASD) display diverse deficits in social, cognitive and behavioral functioning. To date, there has been mixed findings on the profile of executive function deficits for high-functioning adults (IQ > 70) with ASD. A conceptual distinction is commonly made between “cold” and “hot” executive functions. Cold executive functions refer to mechanistic higher-order cognitive operations (e.g., working memory), whereas hot executive functions entail cognitive abilities supported by emotional awareness and social perception (e.g., social cognition). This study aimed to determine the independence of deficits in hot and cold executive functions for high-functioning adults with ASD. Forty-two adults with ASD (64% male, aged 18–66 years) and 40 age and gender matched controls were administered The Awareness of Social Inference Test (TASIT; emotion recognition and social inference), Letter Number Sequencing (working memory) and Hayling Sentence Completion Test (response initiation and suppression). Between-group analyses identified that the ASD group performed significantly worse than matched controls on all measures of cold and hot executive functions (d = 0.54 − 1.5). Hierarchical multiple regression analyses revealed that the ASD sample performed more poorly on emotion recognition and social inference tasks than matched controls after controlling for cold executive functions and employment status. The findings also indicated that the ability to recognize emotions and make social inferences was supported by working memory and response initiation and suppression processes. Overall, this study supports the distinction between hot and cold executive function impairments for adults with ASD. Moreover, it advances understanding of higher-order impairments underlying social interaction difficulties for this population which, in turn, may assist with diagnosis and inform intervention programs. PMID:26903836

On the effect of velocity gradients on the depth of correlation in μPIV

NASA Astrophysics Data System (ADS)

Mustin, B.; Stoeber, B.

2016-03-01

The present work revisits the effect of velocity gradients on the depth of the measurement volume (depth of correlation) in microscopic particle image velocimetry (μPIV). General relations between the μPIV weighting functions and the local correlation function are derived from the original definition of the weighting functions. These relations are used to investigate under which circumstances the weighting functions are related to the curvature of the local correlation function. Furthermore, this work proposes a modified definition of the depth of correlation that leads to more realistic results than previous definitions for the case when flow gradients are taken into account. Dimensionless parameters suitable to describe the effect of velocity gradients on μPIV cross correlation are derived and visual interpretations of these parameters are proposed. We then investigate the effect of the dimensionless parameters on the weighting functions and the depth of correlation for different flow fields with spatially constant flow gradients and with spatially varying gradients. Finally this work demonstrates that the results and dimensionless parameters are not strictly bound to a certain model for particle image intensity distributions but are also meaningful when other models for particle images are used.

Frontal lobe function in temporal lobe epilepsy

PubMed Central

Stretton, J.; Thompson, P.J.

2012-01-01

Summary Temporal lobe epilepsy (TLE) is typically associated with long-term memory dysfunction. The frontal lobes support high-level cognition comprising executive skills and working memory that is vital for daily life functioning. Deficits in these functions have been increasingly reported in TLE. Evidence from both the neuropsychological and neuroimaging literature suggests both executive function and working memory are compromised in the presence of TLE. In relation to executive impairment, particular focus has been paid to set shifting as measured by the Wisconsin Card Sorting Task. Other discrete executive functions such as decision-making and theory of mind also appear vulnerable but have received little attention. With regard to working memory, the medial temporal lobe structures appear have a more critical role, but with emerging evidence of hippocampal dependent and independent processes. The relative role of underlying pathology and seizure spread is likely to have considerable bearing upon the cognitive phenotype and trajectory in TLE. The identification of the nature of frontal lobe dysfunction in TLE thus has important clinical implications for prognosis and surgical management. Longitudinal neuropsychological and neuroimaging studies assessing frontal lobe function in TLE patients pre- and postoperatively will improve our understanding further. PMID:22100147

ON THE BIOMECHANICS OF HEART VALVE FUNCTION

PubMed Central

Sacks, Michael S.; Merryman, W. David; Schmidt, David E.

2009-01-01

Heart valves (HVs) are fluidic control components of the heart that ensure unidirectional blood flow during the cardiac cycle. However, this description does not adequately describe the biomechanical ramifications of their function in that their mechanics are multi-modal. Moreover, they must replicate their cyclic function over an entire lifetime, with an estimated total functional demand of least 3×109 cycles. The focus of the present review is on the functional biomechanics of heart valves. Thus, the focus of the present review is on functional biomechanics, referring primarily to biosolid as well as several key biofluid mechanical aspects underlying heart valve physiological function. Specifically, we refer to the mechanical behaviors of the extra-cellular matrix structural proteins, underlying cellular function, and their integrated relation to the major aspects of valvular hemodynamic function. While we focus on the work from the author’s laboratories, relevant works of other investigators have been included whenever appropriate. We conclude with a summary of important future trends. PMID:19540499

Pain, fatigue and hand function closely correlated to work ability and employment status in systemic sclerosis.

PubMed

Sandqvist, Gunnel; Scheja, Agneta; Hesselstrand, Roger

2010-09-01

To identify factors, individual and work related, influencing work ability, and to assess the association between work ability and employment status, activities of daily life (ADLs) and quality of life in patients with SSc. Fifty-seven consecutive patients (53 females/4 males) with SSc (47 lcSSc/10 dcSSc) were included. Median age was 58 [interquartile range (IQR) 47-62] years and disease duration 14 (9-19) years. The patients were assessed for socio-demographic characteristics, disease parameters, symptoms, work ability, empowerment and adaptations in a workplace, social support, ADLs and quality of life. Work ability, assessed with the Work Ability Index (WAI) could be evaluated in 48 of 57 patients. The correlation between employment status and WAI was good (r(s) = 0.79, P < 0.001). Thirteen patients had good or excellent WAI, 15 had less good and 20 had poor WAI. There were no significant differences between subgroups of WAI and socio-demographic characteristics, disease duration or degree of skin and lung involvement. However, patients with good WAI expressed milder perceived symptoms (pain, fatigue and impaired hand function; P < 0.001). Patients with better WAI had better competence (P < 0.001), better possibility of adaptations at work (P < 0.01) and impact at work (P < 0.01) than those with poorer WAI. In SSc, pain, fatigue and impaired hand function have a dominant impact on the WAI. Employment interventions should include support in job adaptations as well as self-management strategies to help patients deal with pain and fatigue and to enhance the confidence to perform their work.

Effectiveness of Working Memory Training among Subjects Currently on Sick Leave Due to Complex Symptoms.

PubMed

Aasvik, Julie K; Woodhouse, Astrid; Stiles, Tore C; Jacobsen, Henrik B; Landmark, Tormod; Glette, Mari; Borchgrevink, Petter C; Landrø, Nils I

2016-01-01

Introduction: The current study examined if adaptive working memory training (Cogmed QM) has the potential to improve inhibitory control, working memory capacity, and perceptions of memory functioning in a group of patients currently on sick leave due to symptoms of pain, insomnia, fatigue, depression and anxiety. Participants who were referred to a vocational rehabilitation center volunteered to take part in the study. Methods: Participants were randomly assigned to either a training condition ( N = 25) or a control condition ( N = 29). Participants in the training condition received working memory training in addition to the clinical intervention offered as part of the rehabilitation program, while participants in the control condition received treatment as usual i.e., the rehabilitation program only. Inhibitory control was measured by The Stop Signal Task, working memory was assessed by the Spatial Working Memory Test, while perceptions of memory functioning were assessed by The Everyday Memory Questionnaire-Revised. Results: Participants in the training group showed a significant improvement on the post-tests of inhibitory control when compared with the comparison group ( p = 0.025). The groups did not differ on the post-tests of working memory. Both groups reported less memory problems at post-testing, but there was no sizeable difference between the two groups. Conclusions: Results indicate that working memory training does not improve general working memory capacity per se . Nor does it seem to give any added effects in terms of targeting and improving self-perceived memory functioning. Results do, however, provide evidence to suggest that inhibitory control is accessible and susceptible to modification by adaptive working memory training.

E-health to improve work functioning in employees with rheumatoid arthritis in rheumatology practice: a feasibility study.

PubMed

Hoving, J L; Zoer, I; van der Meer, M; van der Straaten, Y; Logtenberg-Rutten, C; Kraak-Put, S; de Vries, N; Tak, P P; Sluiter, J K; Frings-Dresen, M H W

2014-01-01

To evaluate the feasibility of an e-health intervention in rheumatology practice for employees with rheumatoid arthritis (RA) who experience problems with work functioning. Twenty-three out of 90 patients with RA from a hospital rheumatology department, invited by letter, participated in a feasibility study. The 3-month internet e-health programme consisted of a self-management programme using a three-step problem-solving strategy: (step 1) analyse your work problems and opportunities; (step 3) identify solutions; and (step 3) work out a strategy (action plan). Support and personal feedback was provided by a rheumatology nurse. Patients completed assignments, received information, and actively worked on their goals. The main feasibility outcome included satisfaction with the programme. Other feasibility outcomes included usefulness, suitability, website use, and work functioning measured at baseline and/or 3 months using questionnaires, semi-structured interviews, and website data. In total, 95% of the participants were satisfied with the programme, and 96% thought the programme was useful for working RA patients and would recommend the programme to other working RA patients (91%). On the website, all patients at least partially completed the assignments in step 1 and 12 patients completed at least one assignment in step 3. Patients judged the website as well arranged with clear tasks. Patients worked on a range of (individual) goals, resolving work challenges using different strategies and actions. The e-health intervention is a feasible intervention for rheumatology practice justifying further effectiveness evaluation while allowing for further improvements in the selection of RA patients and shaping the intervention.

Generalized Reduction Formula for Discrete Wigner Functions of Multiqubit Systems

NASA Astrophysics Data System (ADS)

Srinivasan, K.; Raghavan, G.

2018-03-01

Density matrices and Discrete Wigner Functions are equally valid representations of multiqubit quantum states. For density matrices, the partial trace operation is used to obtain the quantum state of subsystems, but an analogous prescription is not available for discrete Wigner Functions. Further, the discrete Wigner function corresponding to a density matrix is not unique but depends on the choice of the quantum net used for its reconstruction. In the present work, we derive a reduction formula for discrete Wigner functions of a general multiqubit state which works for arbitrary quantum nets. These results would be useful for the analysis and classification of entangled states and the study of decoherence purely in a discrete phase space setting and also in applications to quantum computing.

An Alternate Set of Basis Functions for the Electromagnetic Solution of Arbitrarily-Shaped, Three-Dimensional, Closed, Conducting Bodies Using Method of Moments

NASA Technical Reports Server (NTRS)

Mackenzie, Anne I.; Baginski, Michael E.; Rao, Sadasiva M.

2008-01-01

In this work, we present an alternate set of basis functions, each defined over a pair of planar triangular patches, for the method of moments solution of electromagnetic scattering and radiation problems associated with arbitrarily-shaped, closed, conducting surfaces. The present basis functions are point-wise orthogonal to the pulse basis functions previously defined. The prime motivation to develop the present set of basis functions is to utilize them for the electromagnetic solution of dielectric bodies using a surface integral equation formulation which involves both electric and magnetic cur- rents. However, in the present work, only the conducting body solution is presented and compared with other data.

20 CFR 645.235 - What types of activities are subject to the administrative cost limit on Welfare-to-Work grants?

Code of Federal Regulations, 2010 CFR

2010-04-01

... WtW including: (i) Accounting, budgeting, financial and cash management functions; (ii) Procurement and purchasing functions; (iii) Property management functions; (iv) Personnel management functions; (v... administrative functions (for example, personnel, procurement, purchasing, property management, accounting and...

Nano-scale investigations of electric-dipole-layer enhanced field and thermionic emission from high current density cathodes

NASA Astrophysics Data System (ADS)

Vlahos, Vasilios

Cesium iodide coated graphitic fibers and scandate cathodes are two important electron emission technologies. The coated fibers are utilized as field emitters for high power microwave sources. The scandate cathodes are promising thermionic cathode materials for pulsed power vacuum electron devices. This work attempts to understand the fundamental physical and chemical relationships between the atomic structure of the emitting cathode surfaces and the superior emission characteristics of these cathodes. Ab initio computational modeling in conjunction with experimental investigations was performed on coated fiber cathodes to understand the origin of their very low turn on electric field, which can be reduced by as much as ten-fold compared to uncoated fibers. Copious amounts of cesium and oxygen were found co-localized on the fiber, but no iodine was detected on the surface. Additional ab initio studies confirmed that cesium oxide dimers could lower the work function significantly. Surface cesium oxide dipoles are therefore proposed as the source of the observed reduction in the turn on electric field. It is also proposed that emission may be further enhanced by secondary electrons from cesium oxide during operation. Thermal conditioning of the coated cathode may be a mechanism by which surface cesium iodide is converted into cesium oxide, promoting the depletion of iodine by formation of volatile gas. Ab initio modeling was also utilized to investigate the stability and work functions of scandate structures. The work demonstrated that monolayer barium-scandium-oxygen surface structures on tungsten can dramatically lower the work function of the underlying tungsten substrate from 4.6 eV down to 1.16 eV, by the formation of multiple surface dipoles. On the basis of this work, we conclude that high temperature kinetics force conventional dispenser cathodes (barium-oxygen monolayers on tungsten) to operate in a non-equilibrium compositional steady state with higher than optimal work functions of ˜2 eV. We hypothesize that scandium enables the barium-oxygen surface monolayer kinetics to access a more thermodynamically stable phase with reported work functions as low as ˜1.3 eV.

Co-morbid depression is associated with poor work outcomes in persons with cardiovascular disease (CVD): A large, nationally representative survey in the Australian population

PubMed Central

2012-01-01

Background Co-morbid major depressive disorder (MDD) and cardiovascular disease (CVD) is associated with poor clinical and psychological outcomes. However, the full extent of the burden of, and interaction between, this co-morbidity on important vocational outcomes remains less clear, particularly at the population level. We examine the association of co-morbid MDD with work outcomes in persons with and without CVD. Methods This study utilised cross-sectional, population-based data from the 2007 Australian National Survey of Mental Health and Wellbeing (n = 8841) to compare work outcomes of individuals with diagnostically-defined MDD and CVD, MDD but not CVD, CVD but not MDD, with a reference group of "healthy" Australians. Workforce participation was defined as being in full- or part-time employment. Work functioning was measured using a WHO Disability Assessment Schedule item. Absenteeism was assessed using the 'days out of role' item. Results Of the four groups, those with co-morbid MDD and CVD were least likely to report workforce participation (adj OR:0.4, 95% CI: 0.3-0.6). Those with MDD only (adj OR:0.8, 95% CI:0.7-0.9) and CVD only (adj OR:0.8, 95% CI: 0.6-0.9) also reported significantly reduced odds of participation. Employed individuals with co-morbid MDD and CVD were 8 times as likely to experience impairments in work functioning (adj OR:8.1, 95% CI: 3.8- 17.3) compared with the reference group. MDD was associated with a four-fold increase in impaired functioning. Further, individuals with co-morbid MDD and CVD reported greatest likelihood of workplace absenteeism (adj. OR:3.0, 95% CI: 1.4-6.6). Simultaneous exposure to MDD and CVD conferred an even greater likelihood of poorer work functioning. Conclusions Co-morbid MDD and CVD is associated with significantly poorer work outcomes. Specifically, the effects of these conditions on work functioning are synergistic. The development of specialised treatment programs for those with co-morbid MDD and CVD is required. PMID:22257700

Cognitive profile in Duchenne muscular dystrophy boys without intellectual disability: The role of executive functions.

PubMed

Battini, R; Chieffo, D; Bulgheroni, S; Piccini, G; Pecini, C; Lucibello, S; Lenzi, S; Moriconi, F; Pane, M; Astrea, G; Baranello, G; Alfieri, P; Vicari, S; Riva, D; Cioni, G; Mercuri, E

2018-02-01

The aim of our prospective observational study was to assess profiles of cognitive function and a possible impairment of executive functions in a cohort of boys with Duchenne muscular dystrophy without intellectual and behavior disability. Forty Duchenne boys (range of age: 6 years to 11 years and 6 months) were assessed by Wechsler Intelligence scale and battery of tests including tasks assessing working memory and executive functions (inhibition and switching, problem solving and planning). In our cohort some aspects of cognitive function were often impaired. These included multitasking, problem solving, inhibition and working memory necessary to plan and direct goal oriented behavior. Our results support the suggestion that aspects of cognitive function could be impaired even in boys without intellectual disability and support the hypothesis that executive functions may play an important role in specific aspects of cognitive impairment in Duchenne muscular dystrophy. Copyright © 2017 Elsevier B.V. All rights reserved.

Introduction to the Special Issue: Discrepancies in Adolescent-Parent Perceptions of the Family and Adolescent Adjustment.

PubMed

De Los Reyes, Andres; Ohannessian, Christine McCauley

2016-10-01

Researchers commonly rely on adolescents' and parents' reports to assess family functioning (e.g., conflict, parental monitoring, parenting practices, relationship quality). Recent work indicates that these reports may vary as to whether they converge or diverge in estimates of family functioning. Further, patterns of converging or diverging reports may yield important information about adolescent adjustment and family functioning. This work is part of a larger literature seeking to understand and interpret multi-informant assessments of psychological phenomena, namely mental health. In fact, recent innovations in conceptualizing, measuring, and analyzing multi-informant mental health assessments might meaningfully inform efforts to understand multi-informant assessments of family functioning. Therefore, in this Special Issue we address three aims. First, we provide a guiding framework for using and interpreting multi-informant assessments of family functioning, informed by recent theoretical work focused on using and interpreting multi-informant mental health assessments. Second, we report research on adolescents' and parents' reports of family functioning that leverages the latest methods for measuring and analyzing patterns of convergence and divergence between informants' reports. Third, we report research on measurement invariance and its role in interpreting adolescents' and parents' reports of family functioning. Research and theory reported in this Special Issue have important implications for improving our understanding of the links between multi-informant assessments of family functioning and adolescent adjustment.

Functional Connectivity among Spikes in Low Dimensional Space during Working Memory Task in Rat

PubMed Central

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. PMID:24658291

Working memory and executive function decline across normal aging, mild cognitive impairment, and Alzheimer's disease.

PubMed

Kirova, Anna-Mariya; Bays, Rebecca B; Lagalwar, Sarita

2015-01-01

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.

Reasoning=working Memory<>attention

ERIC Educational Resources Information Center

Buehner, M.; Krumm, S.; Pick, M.

2005-01-01

The purpose of this study was to clarify the relationship between attention, components of working memory, and reasoning. Therefore, twenty working memory tests, two attention tests, and nine intelligence subtests were administered to 135 students. Using structural equation modeling, we were able to replicate a functional model of working memory…

A Super Contribution to Vocational Theory: Work Values.

ERIC Educational Resources Information Center

Zytowski, Donald G.

1994-01-01

Traces influence of Donald Super in introducing work values into career development/vocational theory. Reviews conceptualization, taxonomy, and assessment of work values. Presents research bearing on Super's "onion model," representing his views on relationship of work values to other affective variables. Reviews research regarding functional role…

T59. VIRTUAL REALTY ASSESSMENT OF FUNCTIONAL CAPACITY IN EARLY SCHIZOPHRENIA: ASSOCIATIONS WITH NEUROCOGNITION, FUNCTIONAL CAPACITY PERFORMANCE, AND DAILY FUNCTIONING

PubMed Central

Ventura, Joseph; Welikson, Tamara; Subotnik, Kenneth L; Ered, Arielle; Keefe, Richard; Hellemann, Gerhard H; Nuechterlein, Keith H

2018-01-01

Abstract Background Research using virtual reality assessment of functional capacity has shown promise as a reliable and valid way to assess treatment response in patients with established schizophrenia. There has been little work on virtual reality based assessments of functional capacity for patients in the early phase of schizophrenia. We examined whether virtual reality based assessment methods reveal functional capacity deficits in young patients and relevant relationships with established measures of neurocognition, functional capacity performance, and daily functioning. Methods The sample consisted of UCLA Aftercare Research Program patients (n=42) who were diagnosed by trained raters administering the SCID and who met criteria for schizophrenia, schizoaffective disorder, or schizophreniform disorder, and screened normal control subjects (n=13). Patients were within 2 years of their first psychotic episode upon clinic entry, were an average of 23.2 years old, and had an average of 12.9 years of education. The Virtual Reality Functional Capacity Assessment Tool (VRFCAT) was the computer-based measure of functional capacity. We used the MATRICS Consensus Cognitive Battery (MCCB) as an objective measure of neurocognition and the UCSD Performance-Based Skills Assessment (UPSA) to assess functional capacity performance. The Global Functioning Scale: Role and Social, and the Role Functioning Scale were used to assess work and school performance, familial interactions, and social functioning. Results We were able to confirm that the deficit in functional capacity performance measured using VRFCAT is present in the early course of schizophrenia in that the patients were slower and committed more errors (M=830.41) as compared with normal controls (M=716.84; t=3.0, p<.01). Virtual reality based assessment of functional capacity was correlated with objective measures of neurocognition (MCCB Overall Composite), r=-.71, p=<.01, standard approaches to functional capacity assessment (UPSA), r=-.66, p=<.01, work and school functioning (r=-.52, p<.01), and level of social relationships (r=-.43, p=<.03), but not familial relationships (r=-.03, p=.87). Interestingly, neither neurocognition (MCCB) nor functional capacity performance (UPSA) were correlated with the level of familial relationships. Discussion We extend previous findings in that even patients in the early course of schizophrenia showed virtual reality based functional capacity performance deficits when compared with normal control subjects. Virtual reality based performance was correlated with neurocognition, suggesting that it may be sensitive to changes in cognition. Furthermore, correlations with everyday work/school and social functioning indicate promise as a co-primary measure to index change in functioning in response to treatment. Interestingly, none of our measures of functional capacity or neurocognition were correlated with familial relationships indicating that the determinates of family interactions might be driven by factors other than cognitive capacities.

Anticipated significant work limitation in primary care consulters with osteoarthritis: a prospective cohort study

PubMed Central

Wilkie, Ross; Phillipson, Chris; Hay, Elaine M; Pransky, Glenn

2014-01-01

Objective To describe the prevalence of expected work limitations (EWL) prior to future retirement age in osteoarthritis consulters, and the associated health, sociodemographic and workplace factors. Design Population-based prospective cohort study. Setting General practices in Staffordshire, England. Participants 297 working adults aged 50–65, who had consulted primary care for osteoarthritis. Outcome EWL was defined using a single question, “Do you think joint pain will limit your ability to work before you reach 69 years old?” Results 51 (17.2%) indicated that joint pain would not limit their ability to work until 69, 79 (26.6%) indicated EWL and 167 (56.2%) did not know if joint pain would limit work before 69. In bivariate analysis, physical function (OR 0.93; 95% CI 0.91 to 0.96), depression (4.51; 1.81 to 11.3), cognitive symptom (3.84; 1.81 to 8.18), current smoker (2.75; 1.02 to 7.38), age (0.69; 0.58 to 0.82), physically demanding job (3.18; 1.50 to 6.72), no opportunities to retrain (3.01; 1.29 to 7.05) and work dissatisfaction (3.69; 1.43 to 9.49) were associated with EWL. The final multivariate model included physical function and age. Conclusions Only one in five osteoarthritis consulters expected that joint pain would not limit their work participation before 69 years of age. Given the expectation for people to work until they are older, the results highlight the increasing need for clinicians to include work participation in their consultation and implement strategies to address work loss/limitation. Targeting pain-related functional limitation and effective communication with employers to manage workplace issues could reduce EWL. PMID:25190616

Working Memory and Decision-Making in a Frontoparietal Circuit Model

PubMed Central

2017-01-01

Working memory (WM) and decision-making (DM) are fundamental cognitive functions involving a distributed interacting network of brain areas, with the posterior parietal cortex (PPC) and prefrontal cortex (PFC) at the core. However, the shared and distinct roles of these areas and the nature of their coordination in cognitive function remain poorly understood. Biophysically based computational models of cortical circuits have provided insights into the mechanisms supporting these functions, yet they have primarily focused on the local microcircuit level, raising questions about the principles for distributed cognitive computation in multiregional networks. To examine these issues, we developed a distributed circuit model of two reciprocally interacting modules representing PPC and PFC circuits. The circuit architecture includes hierarchical differences in local recurrent structure and implements reciprocal long-range projections. This parsimonious model captures a range of behavioral and neuronal features of frontoparietal circuits across multiple WM and DM paradigms. In the context of WM, both areas exhibit persistent activity, but, in response to intervening distractors, PPC transiently encodes distractors while PFC filters distractors and supports WM robustness. With regard to DM, the PPC module generates graded representations of accumulated evidence supporting target selection, while the PFC module generates more categorical responses related to action or choice. These findings suggest computational principles for distributed, hierarchical processing in cortex during cognitive function and provide a framework for extension to multiregional models. SIGNIFICANCE STATEMENT Working memory and decision-making are fundamental “building blocks” of cognition, and deficits in these functions are associated with neuropsychiatric disorders such as schizophrenia. These cognitive functions engage distributed networks with prefrontal cortex (PFC) and posterior parietal cortex (PPC) at the core. It is not clear, however, what the contributions of PPC and PFC are in light of the computations that subserve working memory and decision-making. We constructed a biophysical model of a reciprocally connected frontoparietal circuit that revealed shared and distinct functions for the PFC and PPC across working memory and decision-making tasks. Our parsimonious model connects circuit-level properties to cognitive functions and suggests novel design principles beyond those of local circuits for cognitive processing in multiregional brain networks. PMID:29114071

Working Memory and Decision-Making in a Frontoparietal Circuit Model.

PubMed

Murray, John D; Jaramillo, Jorge; Wang, Xiao-Jing

2017-12-13

Working memory (WM) and decision-making (DM) are fundamental cognitive functions involving a distributed interacting network of brain areas, with the posterior parietal cortex (PPC) and prefrontal cortex (PFC) at the core. However, the shared and distinct roles of these areas and the nature of their coordination in cognitive function remain poorly understood. Biophysically based computational models of cortical circuits have provided insights into the mechanisms supporting these functions, yet they have primarily focused on the local microcircuit level, raising questions about the principles for distributed cognitive computation in multiregional networks. To examine these issues, we developed a distributed circuit model of two reciprocally interacting modules representing PPC and PFC circuits. The circuit architecture includes hierarchical differences in local recurrent structure and implements reciprocal long-range projections. This parsimonious model captures a range of behavioral and neuronal features of frontoparietal circuits across multiple WM and DM paradigms. In the context of WM, both areas exhibit persistent activity, but, in response to intervening distractors, PPC transiently encodes distractors while PFC filters distractors and supports WM robustness. With regard to DM, the PPC module generates graded representations of accumulated evidence supporting target selection, while the PFC module generates more categorical responses related to action or choice. These findings suggest computational principles for distributed, hierarchical processing in cortex during cognitive function and provide a framework for extension to multiregional models. SIGNIFICANCE STATEMENT Working memory and decision-making are fundamental "building blocks" of cognition, and deficits in these functions are associated with neuropsychiatric disorders such as schizophrenia. These cognitive functions engage distributed networks with prefrontal cortex (PFC) and posterior parietal cortex (PPC) at the core. It is not clear, however, what the contributions of PPC and PFC are in light of the computations that subserve working memory and decision-making. We constructed a biophysical model of a reciprocally connected frontoparietal circuit that revealed shared and distinct functions for the PFC and PPC across working memory and decision-making tasks. Our parsimonious model connects circuit-level properties to cognitive functions and suggests novel design principles beyond those of local circuits for cognitive processing in multiregional brain networks. Copyright © 2017 the authors 0270-6474/17/3712167-20$15.00/0.

Quantum Monte Carlo for electronic structure: Recent developments and applications

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

Rodriquez, Maria Milagos Soto

Quantum Monte Carlo (QMC) methods have been found to give excellent results when applied to chemical systems. The main goal of the present work is to use QMC to perform electronic structure calculations. In QMC, a Monte Carlo simulation is used to solve the Schroedinger equation, taking advantage of its analogy to a classical diffusion process with branching. In the present work the author focuses on how to extend the usefulness of QMC to more meaningful molecular systems. This study is aimed at questions concerning polyatomic and large atomic number systems. The accuracy of the solution obtained is determined bymore » the accuracy of the trial wave function`s nodal structure. Efforts in the group have given great emphasis to finding optimized wave functions for the QMC calculations. Little work had been done by systematically looking at a family of systems to see how the best wave functions evolve with system size. In this work the author presents a study of trial wave functions for C, CH, C 2H and C 2H 2. The goal is to study how to build wave functions for larger systems by accumulating knowledge from the wave functions of its fragments as well as gaining some knowledge on the usefulness of multi-reference wave functions. In a MC calculation of a heavy atom, for reasonable time steps most moves for core electrons are rejected. For this reason true equilibration is rarely achieved. A method proposed by Batrouni and Reynolds modifies the way the simulation is performed without altering the final steady-state solution. It introduces an acceleration matrix chosen so that all coordinates (i.e., of core and valence electrons) propagate at comparable speeds. A study of the results obtained using their proposed matrix suggests that it may not be the optimum choice. In this work the author has found that the desired mixing of coordinates between core and valence electrons is not achieved when using this matrix. A bibliography of 175 references is included.« less

Multimodal MRI reveals structural connectivity differences in 22q11 deletion syndrome related to impaired spatial working memory.

PubMed

O'Hanlon, Erik; Howley, Sarah; Prasad, Sarah; McGrath, Jane; Leemans, Alexander; McDonald, Colm; Garavan, Hugh; Murphy, Kieran C

2016-12-01

Impaired spatial working memory is a core cognitive deficit observed in people with 22q11 Deletion syndrome (22q11DS) and has been suggested as a candidate endophenotype for schizophrenia. However, to date, the neuroanatomical mechanisms describing its structural and functional underpinnings in 22q11DS remain unclear. We quantitatively investigate the cognitive processes and associated neuroanatomy of spatial working memory in people with 22q11DS compared to matched controls. We examine whether there are significant between-group differences in spatial working memory using task related fMRI, Voxel based morphometry and white matter fiber tractography. Multimodal magnetic resonance imaging employing functional, diffusion and volumetric techniques were used to quantitatively assess the cognitive and neuroanatomical features of spatial working memory processes in 22q11DS. Twenty-six participants with genetically confirmed 22q11DS aged between 9 and 52 years and 26 controls aged between 8 and 46 years, matched for age, gender, and handedness were recruited. People with 22q11DS have significant differences in spatial working memory functioning accompanied by a gray matter volume reduction in the right precuneus. Gray matter volume was significantly correlated with task performance scores in these areas. Tractography revealed extensive differences along fibers between task-related cortical activations with pronounced differences localized to interhemispheric commissural fibers within the parietal section of the corpus callosum. Abnormal spatial working memory in 22q11DS is associated with aberrant functional activity in conjunction with gray and white matter structural abnormalities. These anomalies in discrete brain regions may increase susceptibility to the development of psychiatric disorders such as schizophrenia. Hum Brain Mapp 37:4689-4705, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Stability of whole brain and regional network topology within and between resting and cognitive states.

PubMed

Rzucidlo, Justyna K; Roseman, Paige L; Laurienti, Paul J; Dagenbach, Dale

2013-01-01

Graph-theory based analyses of resting state functional Magnetic Resonance Imaging (fMRI) data have been used to map the network organization of the brain. While numerous analyses of resting state brain organization exist, many questions remain unexplored. The present study examines the stability of findings based on this approach over repeated resting state and working memory state sessions within the same individuals. This allows assessment of stability of network topology within the same state for both rest and working memory, and between rest and working memory as well. fMRI scans were performed on five participants while at rest and while performing the 2-back working memory task five times each, with task state alternating while they were in the scanner. Voxel-based whole brain network analyses were performed on the resulting data along with analyses of functional connectivity in regions associated with resting state and working memory. Network topology was fairly stable across repeated sessions of the same task, but varied significantly between rest and working memory. In the whole brain analysis, local efficiency, Eloc, differed significantly between rest and working memory. Analyses of network statistics for the precuneus and dorsolateral prefrontal cortex revealed significant differences in degree as a function of task state for both regions and in local efficiency for the precuneus. Conversely, no significant differences were observed across repeated sessions of the same state. These findings suggest that network topology is fairly stable within individuals across time for the same state, but also fluid between states. Whole brain voxel-based network analyses may prove to be a valuable tool for exploring how functional connectivity changes in response to task demands.

A functional MRI study of working memory task in euthymic bipolar disorder: evidence for task-specific dysfunction.

PubMed

Monks, Paul J; Thompson, Jill M; Bullmore, Edward T; Suckling, John; Brammer, Michael J; Williams, Steve C R; Simmons, Andrew; Giles, Nicola; Lloyd, Adrian J; Harrison, C Louise; Seal, Marc; Murray, Robin M; Ferrier, I Nicol; Young, Allan H; Curtis, Vivienne A

2004-12-01

Even when euthymic bipolar disorder patients can have persistent deficits in working memory, but the neural basis of this deficit remains unclear. We undertook an functional magnetic resonance imaging investigation of euthymic bipolar disorder patients performing two working memory paradigms; the two-back and Sternberg tasks, selected to examine the central executive and the phonological loop respectively. We hypothesized that neuronal dysfunction would be specific to the network underlying the executive rather than the phonological loop component of working memory. Twelve right-handed euthymic bipolar I males receiving lithium carbonate monotherapy were matched with 12 controls. The two-back task comprised a single working memory load contrasted with baseline vigilance condition. The Sternberg paradigm used a parametric design incorporating variable working memory load with fixed delay between presentation of an array of items to be remembered and a target item. Functional activation data were acquired during performance of the tasks and were analysed to produce brain activation maps representing significant group differences in activation (ANOVA). Load-response curves were derived from the Sternberg task data set. There were no significant between-group differences (t-test) in performance of the two-back task, or in 2 x 5 group by memory load ANOVA for the performance data from Sternberg task. In the two-back task, compared with controls bipolar disorder patients showed reductions in bilateral frontal, temporal and parietal activation, and increased activations with the left precentral, right medial frontal and left supramarginal gyri. No between-group differences were observed in the Sternberg task at any working memory load. Our findings support the notion that, in euthymic bipolar disorder, failure to engage fronto-executive function underpins the core neuropsychological deficits. Blackwell Munksgaard, 2004

Brexpiprazole as an adjunctive treatment in young adults with major depressive disorder who are in a school or work environment.

PubMed

Weisler, Richard H; Ota, Ai; Tsuneyoshi, Kana; Perry, Pamela; Weiller, Emmanuelle; Baker, Ross A; Sheehan, David V

2016-11-01

Major depressive disorder (MDD) is a common, debilitating disorder with substantial socioeconomic burden. Many patients with MDD experience symptoms that impair functioning and productivity, often negatively affecting work or educational pursuits. This Phase 3b open-label study evaluated adjunctive brexpiprazole in young adults with MDD, who were in work or study. Young patients (18-35 years) with MDD (inadequate responders to 1-3 antidepressant treatments [ADT] for their current episode) received brexpiprazole 1-3mg/day (target dose, 2mg/day) adjunctive to the same stable dose of ADT for 12 weeks. Depressive symptoms improved during treatment with adjunctive brexpiprazole (primary endpoint, least squares [LS] mean change from baseline in Montgomery-Åsberg Depression Rating Scale [MADRS] total score, -18.1 [p<0.0001]). Reductions from baseline in Sheehan Disability Scale Score (SDS; LS mean change -11.2 [p<0.0001]) and Work Limitations Questionnaire (WLQ; p<0.0001) indicated improvements in the effects of patients' symptoms on functioning (work/school, social life, and home responsibilities). Changes from baseline in additional measures supported improvements in patient functioning and depression symptoms. The most common adverse events were headache (21.3%), weight increase (17.0%), and somnolence (17.0%); reported rates of akathisia were low (6.4%). Clinically relevant increases in weight (≥7%) occurred in 10.5% of patients. Open-label design; absence of comparator. Brexpiprazole may represent an effective therapy for adjunctive treatment strategy of young adults with MDD who are working or studying. The observed improvements in work/school functioning in patients with MDD, whose depression was treated with ADT+brexpiprazole, suggests potential to reduce socioeconomic burden. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

Kidney function tests

MedlinePlus

Kidney function tests are common lab tests used to evaluate how well the kidneys are working. Such tests include: ... Oh MS, Briefel G. Evaluation of renal function, water, electrolytes ... and Management by Laboratory Methods . 23rd ed. Philadelphia, ...

Liver function tests

MedlinePlus

Liver function tests are common tests that are used to see how well the liver is working. Tests include: ... E, Bowne WB, Bluth MH. Evaluation of liver function. In: McPherson RA, Pincus MR, eds. Henry's Clinical ...

DoD Weapon System Acquisition Reform Product Support Assessment

DTIC Science & Technology

2009-11-01

can be best effected by working through the Defense Acquisition University, the Logistics Functional IPT, the Acquisition Management Functional... WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) Department of Defense,Undersecretary of Defense for Acquisition,Technology and...each year in product support. Reformed stewardship—driven by improving product support and achieving more cost- effective weapon system readiness

Emotional-volitional components of operator reliability. [sensorimotor function testing under stress

NASA Technical Reports Server (NTRS)

Mileryan, Y. A.

1975-01-01

Sensorimotor function testing in a tracking task under stressfull working conditions established a psychological characterization for a successful aviation pilot: Motivation significantly increased the reliability and effectiveness of their work. Their acitivities were aimed at suppressing weariness and the feeling of fear caused by the stress factors; they showed patience, endurance, persistence, and a capacity for lengthy volitional efforts.

Barium-Dispenser Thermionic Cathode

NASA Technical Reports Server (NTRS)

Wintucky, Edwin G.; Green, M.; Feinleib, M.

1989-01-01

Improved reservoir cathode serves as intense source of electrons required for high-frequency and often high-output-power, linear-beam tubes, for which long operating lifetime important consideration. High emission-current densities obtained through use of emitting surface of relatively-low effective work function and narrow work-function distribution, consisting of coat of W/Os deposited by sputtering. Lower operating temperatures and enhanced electron emission consequently possible.

Differences in Low and High Working-Memory Capacity Readers' Cognitive and Metacognitive Processing Patterns as a Function of Reading for Different Purposes

ERIC Educational Resources Information Center

Linderholm, Tracy; Cong, Xiaosi; Zhao, Qin

2008-01-01

Differences in cognitive and metacognitive processing patterns as a function of working-memory capacity and reading for different purposes were examined in college-aged readers by collecting reading times and calculating absolute monitoring accuracy, which is the difference between estimated and actual comprehension test performance. Readers read…

Did Michelangelo (1475-1564) have high-functioning autism?

PubMed

Arshad, Muhammad; Fitzgerald, Michael

2004-05-01

In this paper evidence is presented that Michelangelo met the criteria for Asperger's disorder, or high-functioning autism. The evidence relates to his single-minded work routine, unusual lifestyle, limited interests, poor social and communication skills, and issues of life control. Depression and various medical conditions, including gout, renal colic and renal stones, did not stop his obsessive working habits.

Computational work and time on finite machines.

NASA Technical Reports Server (NTRS)

Savage, J. E.

1972-01-01

Measures of the computational work and computational delay required by machines to compute functions are given. Exchange inequalities are developed for random access, tape, and drum machines to show that product inequalities between storage and time, number of drum tracks and time, number of bits in an address and time, etc., must be satisfied to compute finite functions on bounded machines.

Working Memory as a Predictor of Written Arithmetical Skills in Children: The Importance of Central Executive Functions

ERIC Educational Resources Information Center

Andersson, Ulf

2008-01-01

Background: The study was conducted in an attempt to further our understanding of how working memory contributes to written arithmetical skills in children. Aim: The aim was to pinpoint the contribution of different central executive functions and to examine the contribution of the two subcomponents of children's written arithmetical skills.…

At the Intersection of Attention and Memory: The Mechanistic Role of the Posterior Parietal Lobe in Working Memory

ERIC Educational Resources Information Center

Berryhill, Marian E.; Chein, Jason; Olson, Ingrid R.

2011-01-01

Portions of the posterior parietal cortex (PPC) play a role in working memory (WM) yet the precise mechanistic function of this region remains poorly understood. The "pure storage" hypothesis proposes that this region functions as a short-lived modality-specific memory store. Alternatively, the "internal attention" hypothesis proposes that the PPC…

The Criticality of Norms to the Functional Imperatives of the Social Action System of College and University Work

ERIC Educational Resources Information Center

Braxton, John M.

2010-01-01

In this article, I assert that the work of colleges and universities forms a social action system. I array the critical positions represented in this issue according to the four functional imperatives of social action systems: adaptation, goal attainment, integration, and pattern maintenance. I discuss the role of normative structures for these…

A Short Biography of Paul A. M. Dirac and Historical Development of Dirac Delta Function

ERIC Educational Resources Information Center

Debnath, Lokenath

2013-01-01

This paper deals with a short biography of Paul Dirac, his first celebrated work on quantum mechanics, his first formal systematic use of the Dirac delta function and his famous work on quantum electrodynamics and quantum statistics. Included are his first discovery of the Dirac relativistic wave equation, existence of positron and the intrinsic…

Enhancing the Interdisciplinary Perspective in the Marketing Management Decision Process through an Applied, Integrated, Client Project

ERIC Educational Resources Information Center

Askim-Lovseth, Mary K.; O'Keefe, Timothy P.

2012-01-01

Businesses function within a cross-functional, integrative setting, and this necessitates providing a learning environment for students that is comparable to real-life work projects. Two upper-level university classes in marketing and information systems worked collaboratively with a snack food business to design and build a Web site based on a…

A Preliminary Study of the Validity of Memory Tests Recommended by the Working Group for Individuals with Moderate to Severe Intellectual Disability

ERIC Educational Resources Information Center

Pyo, G.; Kripakaran, K.; Curtis, K.; Curtis, R.; Markwell, S.

2007-01-01

Background: Normal aging and Dementia of Alzheimer's Type (DAT) among higher functioning individuals with intellectual disability (ID) have been relatively well studied using a variety of cognitive tests. However, cognitive studies for lower functioning individuals with ID are scarce in the literature. The Working Group recommended the Test…

A Cross-Sectional and Follow-Up Functional MRI Study with a Working Memory Task in Adolescent Anorexia Nervosa

ERIC Educational Resources Information Center

Castro-Fornieles, Josefina; Caldu, Xavier; Andres-Perpina, Susana; Lazaro, Luisa; Bargallo, Nuria; Falcon, Carles; Plana, Maria Teresa; Junque, Carme

2010-01-01

Structural and functional brain abnormalities have been described in anorexia nervosa (AN). The objective of this study was to examine whether there is abnormal regional brain activation during a working memory task not associated with any emotional stimuli in adolescent patients with anorexia and to detect possible changes after weight recovery.…

Low Work Function 2.81 eV Rb2CO3-Doped Polyethylenimine Ethoxylated for Inverted Organic Light-Emitting Diodes.

PubMed

Kim, Jeonggi; Kim, Hyo-Min; Jang, Jin

2018-06-06

We report a low work function (2.81 eV), Rb 2 CO 3 -doped polyethyleneimine ethoxylated (PEIE) which is used for highly efficient and long-lifetime, inverted organic light-emitting diodes (OLEDs). Doping Rb 2 CO 3 into PEIE decreases the work function of Li-doped ZnO (LZO) by 1.0 eV and thus significantly improves electron injection ability into the emission layer (EML). The inverted OLED with PEIE:Rb 2 CO 3 interfacial layer (IL) exhibits higher efficiency and longer operation lifetime than those of the device with a PEIE IL. It is found also that Mg-doped ZnO (MZO) can be used instead of LZO as electron transporting layer. Rb 2 CO 3 shows a low work function of 2.81 eV. The OLED with MZO/PEIE:Rb 2 CO 3 exhibits low operating voltage of 5.0 V at 1000 cd m -2 and low efficiency roll-off of 11.8% at high luminance of 10 000 cd m -2 . The results are due to the suppressed exciton quenching at the MZO/organic EML interface.

Solution processed ZnO hybrid nanocomposite with tailored work function for improved electron transport layer in organic photovoltaic devices.

PubMed

Lee, Yun-Ju; Wang, Jian; Cheng, Samuel R; Hsu, Julia W P

2013-09-25

We demonstrate improved organic photovoltaic device performance using solution processed electron transport layers of ZnO nanoparticle (NP) films containing organic additives, poly(vinylpyrrolidone) (PVP), or diethanolamine (DEA), that do not require post processing after film deposition. Inclusion of PVP or DEA decreased the ZnO work function by 0.4 eV through interfacial dipole formation. While PVP did not change the ZnO NP shape or size, DEA modified the ZnO shape from 5 nm × 15 nm nanorods to 5 nm nanoparticles. At an optimized PVP concentration of 0.7 wt %, ZnO NP:PVP electron transport layers (ETLs) improved the efficiency of inverted P3HT:PCBM devices by 37%, primarily through higher fill factor. ZnO NP:PVP and ZnO NP:DEA ETLs increased the open circuit voltage of inverted P3HT:ICBA devices by 0.07 V due to decreasing ETL work function, leading to enhanced built-in field. The relationship between ZnO nanocomposite ETL work function, donor-acceptor energy offset, and device performance is discussed. The effects of the two additives are compared.

Work capacity, thermal responses and lung function: united kingdom studies in the L.B.P.

PubMed

Weiner, J S

1976-07-01

Results of physiological studies from some ten U.K. Human Adaptability projects are presented. U.K. investigators made major contributions in developing and adapting techniques for the assussment under field conditions of work capacity, heat tolerance and respiratory function. The various ethnic studies of work capacity revealed the special role of body size and muscularity, as well as training, in determining the observed inter- and intra-population variance. The results on samples from U.K., New Guinea, the Caribbean, Israel, West and East Africa and the Ethiopian highlands gave no indication that genetic difference were significant in determining population differences. Differences in heat tolerance reflect in general the intensity of heat exposure, especially when combined with hard physical work. Indigenous peoples in Africa and New Guinea show some modification in sweating responses which do not appear to be genetically determined but are in some way, as yet not clearly established, attributable to long continued residence in tropical climates. In renal function of some seven ethnic groups were analysed in terms of lung volume bellows function, gas exchange and responses to excercise and carbon dioxide. The relative importance of genetic and non-genetic factors was examined.

A novel gate and drain engineered charge plasma tunnel field-effect transistor for low sub-threshold swing and ambipolar nature

NASA Astrophysics Data System (ADS)

Yadav, Dharmendra Singh; Raad, Bhagwan Ram; Sharma, Dheeraj

2016-12-01

In this paper, we focus on the improvement of figures of merit for charge plasma based tunnel field-effect transistor (TFET) in terms of ON-state current, threshold voltage, sub-threshold swing, ambipolar nature, and gate to drain capacitance which provides better channel controlling of the device with improved high frequency response at ultra-low supply voltages. Regarding this, we simultaneously employ work function engineering on the drain and gate electrode of the charge plasma TFET. The use of gate work function engineering modulates the barrier on the source/channel interface leads to improvement in the ON-state current, threshold voltage, and sub-threshold swing. Apart from this, for the first time use of work function engineering on the drain electrode increases the tunneling barrier for the flow of holes on the drain/channel interface, it results into suppression of ambipolar behavior. The lowering of gate to drain capacitance therefore enhanced high frequency parameters. Whereas, the presence of dual work functionality at the gate electrode and over the drain region improves the overall performance of the charge plasma based TFET.

Composite films of oxidized multiwall carbon nanotube and poly(3,4-ethylenedioxythiophene): polystyrene sulfonate (PEDOT:PSS) as a contact electrode for transistor and inverter devices.

PubMed

Yun, Dong-Jin; Rhee, Shi-Woo

2012-02-01

Composite films of multiwall carbon nanotube (MWNT)/poly(3,4-ethylenedioxythiophene) polymerized with poly(4-styrenesulfonate) (PEDOT:PSS) were prepared by spin-coating a mixture solution. The effect of the MWNT loading and the MWNT oxidation, with acid solution or ultraviolet (UV)-ozone treatment, on the film properties such as surface roughness, work function, surface energy, optical transparency and conductivity were studied. Also pentacene thin film transistors and inverters were made with these composite films as a contact metal and the device characteristics were measured. The oxidation of MWNT reduced the conductivity of MWNT/PEDOT:PSS composite film but increased the work function and transparency. UV-ozone treated MWNT/PEDOT:PSS composite film showed higher conductivity (14000 Ω/□) and work function (4.9 eV) than acid-oxidized MWNT/PEDOT:PSS composite film and showed better performance as a source/drain electrode in organic thin film transistor (OTFT) than other types of MWNT/PEDOT:PSS composite films. Hole injection barrier of the UV-ozone treated MWNT/PEDOT:PSS composite film with pentacene was significantly lower than any other films because of the higher work function.

The cathode material for a plasma-arc heater

NASA Astrophysics Data System (ADS)

Yelyutin, A. V.; Berlin, I. K.; Averyanov, V. V.; Kadyshevskii, V. S.; Savchenko, A. A.; Putintseva, R. G.

1983-11-01

The cathode of a plasma arc heater experiences a large thermal load. The temperature of its working surface, which is in contact with the plasma, reaches high values, as a result of which the electrode material is subject to erosion. Refractory metals are usually employed for the cathode material, but because of the severe erosion do not usually have a long working life. The most important electrophysical characteristic of the electrode is the electron work function. The use of materials with a low electron work function allows a decrease in the heat flow to the cathode, and this leads to an increase in its erosion resistance and working life. The electroerosion of certain materials employed for the cathode in an electric arc plasma generator in the process of reduction smelting of refractory metals was studied.

Automated Work Package: Conceptual Design and Data Architecture

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

Al Rashdan, Ahmad; Oxstrand, Johanna; Agarwal, Vivek

The automated work package (AWP) is one of the U.S. Department of Energy’s (DOE) Light Water Reactor Sustainability Program efforts to enhance the safety and economics of the nuclear power industry. An AWP is an adaptive and interactive work package that intelligently drives the work process according to the plant condition, resources status, and users progress. The AWP aims to automate several manual tasks of the work process to enhance human performance and reduce human errors. Electronic work packages (eWPs), studied by the Electric Power Research Institute (EPRI), are work packages that rely to various extent on electronic data processingmore » and presentation. AWPs are the future of eWPs. They are envisioned to incorporate the advanced technologies of the future, and thus address the unresolved deficiencies associated with the eWPs in a nuclear power plant. In order to define the AWP, it is necessary to develop an ideal envisioned scenario of the future work process without any current technology restriction. The approach followed to develop this scenario is specific to every stage of the work process execution. The scenario development resulted in fifty advanced functionalities that can be part of the AWP. To rank the importance of these functionalities, a survey was conducted involving several U.S. nuclear utilities. The survey aimed at determining the current need of the nuclear industry with respect to the current work process, i.e. what the industry is satisfied with, and where the industry envisions potential for improvement. The survey evaluated the most promising functionalities resulting from the scenario development. The results demonstrated a significant desire to adopt the majority of these functionalities. The results of the survey are expected to drive the Idaho National Laboratory (INL) AWP research and development (R&D). In order to facilitate this mission, a prototype AWP is needed. Since the vast majority of earlier efforts focused on the frontend aspects of the AWP, the backend data architecture was researched and developed in this effort. The backend design involved data architecture aspects. It was realized through this effort that the key aspects of this design are hierarchy, data configuration and live information, data templates and instances, the flow of work package execution, the introduction of properties, and the means to interface the backend to the frontend. After the backend design was developed, a data structure was built to reflect the developed data architecture. The data structure was developed to accommodate the fifty functionalities identified by the envisioned scenario development. The data structure was evaluated by incorporating an example work order from the nuclear power industry. The implementation resulted in several optimization iterations of the data structure. In addition, the rearrangement of the work order information to fit the data structure highlighted several possibilities for improvement in the current work order design, and significantly reduced the size of the work order.« less

Labor supply functions of working male and female pharmacists: In search of the backward bend.

PubMed

Carvajal, Manuel J; Deziel, Lisa; Armayor, Graciela M

2012-01-01

Previous research has shown that U.S. pharmacists experience negative elasticities along a backward-bending labor supply function. The presence of a backward bend in the labor supply curve may cause a decrease in the amount of work at a time of labor shortage. Therefore, the determinants of pharmacists' labor supply functions should be explored to assess the impact of this backward bend. To determine whether female and male pharmacist work inputs are influenced by the same factors and estimate where the backward bend occurs, if at all, in their labor supply functions. Data were collected using a survey questionnaire mailed to registered pharmacists in South Florida. Labor supply functions were formulated and tested separately for 558 men and 498 women. The wage rate, other household income, human capital stock, job-related preferences, and opinion variables were hypothesized to explain labor supply differentials. Human capital stock variables included professional experience, holding a specialty board certification, and number of children; job-related preference variables included urban-rural location of work site and main role as a practitioner; and opinion variables included stress, autonomy, fairness in the workplace, flexibility, and job security. Men and women responded differently to identical stimuli, and their supply functions were influenced in different ways by the explanatory variables. Both genders exhibited positive labor supply elasticities greater than those reported in other studies. Both genders' backward bend in their labor supply functions occurred several standard deviations to the right of the mean. The backward bend in the labor supply functions of male and female pharmacists is not likely to affect in the near future the labor market's ability to regulate shortages of practitioners via increases in the wage rate. A more thorough understanding of pharmacists' labor supply functions must address gender issues and differences in response to identical stimuli. Copyright © 2012 Elsevier Inc. All rights reserved.