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

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.

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

PubMed

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

2012-02-01

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

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.

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.

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.

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

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.

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.

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…

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.

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/

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

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

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, 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.

Thermionic Properties of Carbon Based Nanomaterials Produced by Microhollow Cathode PECVD

NASA Technical Reports Server (NTRS)

Haase, John R.; Wolinksy, Jason J.; Bailey, Paul S.; George, Jeffrey A.; Go, David B.

2015-01-01

Thermionic emission is the process in which materials at sufficiently high temperature spontaneously emit electrons. This process occurs when electrons in a material gain sufficient thermal energy from heating to overcome the material's potential barrier, referred to as the work function. For most bulk materials very high temperatures (greater than 1500 K) are needed to produce appreciable emission. Carbon-based nanomaterials have shown significant promise as emission materials because of their low work functions, nanoscale geometry, and negative electron affinity. One method of producing these materials is through the process known as microhollow cathode PECVD. In a microhollow cathode plasma, high energy electrons oscillate at very high energies through the Pendel effect. These high energy electrons create numerous radical species and the technique has been shown to be an effective method of growing carbon based nanomaterials. In this work, we explore the thermionic emission properties of carbon based nanomaterials produced by microhollow cathode PECVD under a variety of synthesis conditions. Initial studies demonstrate measureable current at low temperatures (approximately 800 K) and work functions (approximately 3.3 eV) for these materials.

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.

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.

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

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.

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.

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.

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.

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.

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.

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.

Graphene for thermoelectronic solar energy conversion

NASA Astrophysics Data System (ADS)

De, Dilip K.; Olukunle, Olawole C.

2017-08-01

Graphene is a high temperature material which can stand temperature as high as 4600 K in vacuum. Even though its work function is high (4.6 eV) the thermionic emission current density at such temperature is very high. Graphene is a wonderful material whose work function can be engineered as desired. Kwon et al41 reported a chemical approach to reduce work function of graphene using K2CO3, Li2CO3, Rb2CO3, Cs2CO3. The work functions are reported to be 3.7 eV, 3.8 eV, 3.5 eV and 3.4 eV. Even though they did not report the high temperature tolerance of such alkali metal carbonate doped graphene, their works open a great promise for use of pure graphene and doped graphene as emitter (cathode) and collector (anode) in a solar thermionic energy converter. This paper discusses the dynamics of solar energy conversion to electrical energy using thermionic energy converter with graphene as emitter and collector. We have considered parabolic mirror concentrator to focus solar energy onto the emitter to achieve temperature around 4300 K. Our theoretical calculations and the modelling show that efficiency as high as 55% can easily be achieved if space-charge problem can be reduced and the collector can be cooled to certain proper temperature. We have discussed methods of controlling the associated space-charge problems. Richardson-Dushman equation modified by the authors have been used in this modelling. Such solar energy conversion would reduce the dependence on silicon solar panel and has great potential for future applications.

An organic surface modifier to produce a high work function transparent electrode for high performance polymer solar cells.

PubMed

Choi, Hyosung; Kim, Hak-Beom; Ko, Seo-Jin; Kim, Jin Young; Heeger, Alan J

2015-02-04

Modification of an ITO electrode with small-molecule organic surface modifier, 4-chloro-benzoic acid (CBA), via a simple spin-coating method produces a high-work-function electrode with high transparency and a hydrophobic surface. As an alternative to PEDOT:PSS, CBA modification achieves efficiency enhancement up to 8.5%, which is attributed to enhanced light absorption within the active layer and smooth hole transport from the active layer to the anode. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

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

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.

To work or not to work: motivation (not low IQ) determines symptom validity test findings.

PubMed

Chafetz, Michael D; Prentkowski, Erica; Rao, Aparna

2011-06-01

Social Security Disability Determinations Service (DDS) claimants are seeking compensation for an inability to work (Chafetz, 2010). These usually low-functioning claimants fail Symptom Validity Tests (SVTs) at high rates (Chafetz, 2008), typically over 40%. In contrast, claimants for the Rehabilitation Service in Louisiana (LRS) are seeking to work. Individuals referred by the Department of Child and Family Services (DCFS) are seeking reunification with their children. All three groups consisted of equivalently low-IQ claimants when considering only those who passed SVTs. Only the DDS group failed SVTs at high rates, whereas LRS claimants failed at minimal rates and DCFS claimants did not fail. Thus, intrinsic motivation explains effort in this particular study of low-functioning claimants: those seeking to work or to look good to reunify with their children pass SVTs at high rates.

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 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.

[Functional state of various physiological systems of the human body during respiration of neon-oxygen mixture at depth up to 400 meters].

PubMed

Poleshuk, I P; Genin, A M; Unku, R D; Mikhnenko, A E; Sementsov, V N; Suvorov, A V

1991-01-01

Hyperbaric neon-oxygen mixture has been studied for the effect of its high density under pressure of 41 ata on basic physiological functions of human organism. Typical changes of the cardiorespiratory system and tissue respiration parameters are revealed. Changes in physical working capacity are shown. Exposure to gaseous medium of high pressure and density is accompanied by the development of some compensatory-adaptive reactions. The possibility to perform mid-hard physical work is attained with overstrain of respiration and circulation function.

Adverse Childhood Experiences, Support, and the Perception of Ability to Work in Adults with Disability.

PubMed

Schüssler-Fiorenza Rose, Sophia Miryam; Eslinger, Jessica G; Zimmerman, Lindsey; Scaccia, Jamie; Lai, Betty S; Lewis, Catrin; Alisic, Eva

2016-01-01

To examine the impact of adverse childhood experiences (ACEs) and support on self-reported work inability of adults reporting disability. Adults (ages 18-64) who participated in the Behavioral Risk Factor Surveillance System in 2009 or 2010 and who reported having a disability (n = 13,009). The study used a retrospective cohort design with work inability as the main outcome. ACE categories included abuse (sexual, physical, emotional) and family dysfunction (domestic violence, incarceration, mental illness, substance abuse, divorce). Support included functional (perceived emotional/social support) and structural (living with another adult) support. Logistic regression was used to adjust for potential confounders (age, sex and race) and to evaluate whether there was an independent effect of ACEs on work inability after adding other important predictors (support, education, health) to the model. ACEs were highly prevalent with almost 75% of the sample reporting at least one ACE category and over 25% having a high ACE burden (4 or more categories). ACEs were strongly associated with functional support. Participants experiencing a high ACE burden had a higher adjusted odds ratio (OR) [95% confidence interval] of 1.9 [1.5-2.4] of work inability (reference: zero ACEs). Good functional support (adjusted OR 0.52 [0.42-0.63]) and structural support (adjusted OR 0.48 [0.41-0.56]) were protective against work inability. After adding education and health to the model, ACEs no longer appeared to have an independent effect. Structural support remained highly protective, but functional support only appeared to be protective in those with good physical health. ACEs are highly prevalent in working-age US adults with a disability, particularly young adults. ACEs are associated with decreased support, lower educational attainment and worse adult health. Health care providers are encouraged to screen for ACEs. Addressing the effects of ACEs on health and support, in addition to education and retraining, may increase ability to work in those with a disability.

Assessment and Classification of Cognitive Decrements Associated with High Workload and Extended Work Periods in a UAV Setting

DTIC Science & Technology

2008-07-01

Percentage of distracters hit for the high workload condition as a function of time-on- task...a function of time-on- task .... 8 Figure 4. Effort scores for the high workload condition as a function of time-on-task ................ 9...Figure 5. Mental demand for the high workload condition as a function of time-on-task ........... 9 Figure 6. Average power for site Oz, alpha band

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.

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.

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

Do the effects of working memory training depend on baseline ability level?

PubMed

Foster, Jeffrey L; Harrison, Tyler L; Hicks, Kenny L; Draheim, Christopher; Redick, Thomas S; Engle, Randall W

2017-11-01

There is a debate about the ability to improve cognitive abilities such as fluid intelligence through training on tasks of working memory capacity. The question addressed in the research presented here is who benefits the most from training: people with low cognitive ability or people with high cognitive ability? Subjects with high and low working memory capacity completed a 23-session study that included 3 assessment sessions, and 20 sessions of training on 1 of 3 training regiments: complex span training, running span training, or an active-control task. Consistent with other research, the authors found that training on 1 executive function did not transfer to ability on a different cognitive ability. High working memory subjects showed the largest gains on the training tasks themselves relative to the low working memory subjects-a finding that suggests high spans benefit more than low spans from training with executive function tasks. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

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

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.

CONSIDERATIONS FOR FAILURE PREVENTION IN AEROSPACE ELECTRICAL POWER SYSTEMS UTILIZING HIGHER VOLTAGES

DTIC Science & Technology

2017-07-01

work , the guideline document (1) provides a basis for identifying high voltage design risks, (2) defines areas of concern as a function of environment ... work , the guideline document 1) provides a basis for identifying high voltage design risks, 2) defines areas of concern as a function of environment ...pressures (y-axis - breakdown voltage [volts-peak]) As an example of the impact of the aerospace environment , consider the calculation of the safe

Central Executive Dysfunction and Deferred Prefrontal Processing in Veterans with Gulf War Illness.

PubMed

Hubbard, Nicholas A; Hutchison, Joanna L; Motes, Michael A; Shokri-Kojori, Ehsan; Bennett, Ilana J; Brigante, Ryan M; Haley, Robert W; Rypma, Bart

2014-05-01

Gulf War Illness is associated with toxic exposure to cholinergic disruptive chemicals. The cholinergic system has been shown to mediate the central executive of working memory (WM). The current work proposes that impairment of the cholinergic system in Gulf War Illness patients (GWIPs) leads to behavioral and neural deficits of the central executive of WM. A large sample of GWIPs and matched controls (MCs) underwent functional magnetic resonance imaging during a varied-load working memory task. Compared to MCs, GWIPs showed a greater decline in performance as WM-demand increased. Functional imaging suggested that GWIPs evinced separate processing strategies, deferring prefrontal cortex activity from encoding to retrieval for high demand conditions. Greater activity during high-demand encoding predicted greater WM performance. Behavioral data suggest that WM executive strategies are impaired in GWIPs. Functional data further support this hypothesis and suggest that GWIPs utilize less effective strategies during high-demand WM.

Central Executive Dysfunction and Deferred Prefrontal Processing in Veterans with Gulf War Illness

PubMed Central

Hubbard, Nicholas A.; Hutchison, Joanna L.; Motes, Michael A.; Shokri-Kojori, Ehsan; Bennett, Ilana J.; Brigante, Ryan M.; Haley, Robert W.; Rypma, Bart

2015-01-01

Gulf War Illness is associated with toxic exposure to cholinergic disruptive chemicals. The cholinergic system has been shown to mediate the central executive of working memory (WM). The current work proposes that impairment of the cholinergic system in Gulf War Illness patients (GWIPs) leads to behavioral and neural deficits of the central executive of WM. A large sample of GWIPs and matched controls (MCs) underwent functional magnetic resonance imaging during a varied-load working memory task. Compared to MCs, GWIPs showed a greater decline in performance as WM-demand increased. Functional imaging suggested that GWIPs evinced separate processing strategies, deferring prefrontal cortex activity from encoding to retrieval for high demand conditions. Greater activity during high-demand encoding predicted greater WM performance. Behavioral data suggest that WM executive strategies are impaired in GWIPs. Functional data further support this hypothesis and suggest that GWIPs utilize less effective strategies during high-demand WM. PMID:25767746

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.

Do Effort and Reward at Work Predict Changes in Cognitive Function? First Longitudinal Results from the Representative German Socio-Economic Panel.

PubMed

Riedel, Natalie; Siegrist, Johannes; Wege, Natalia; Loerbroks, Adrian; Angerer, Peter; Li, Jian

2017-11-15

It has been suggested that work characteristics, such as mental demands, job control, and occupational complexity, are prospectively related to cognitive function. However, current evidence on links between psychosocial working conditions and cognitive change over time is inconsistent. In this study, we applied the effort-reward imbalance model that allows to build on previous research on mental demands and to introduce reward-based learning as a principle with beneficial effect on cognitive function. We aimed to investigate whether high effort, high reward, and low over-commitment in 2006 were associated with positive changes in cognitive function in terms of perceptual speed and word fluency (2006-2012), and whether the co-manifestation of high effort and high reward would yield the strongest association. To this end, we used data on 1031 employees who participated in a large and representative study. Multivariate linear regression analyses supported our main hypotheses (separate and combined effects of effort and reward), particularly on changes in perceptual speed, whereas the effects of over-commitment did not reach the level of statistical significance. Our findings extend available knowledge by examining the course of cognitive function over time. If corroborated by further evidence, organization-based measures in the workplace can enrich efforts towards preventing cognitive decline in ageing workforces.

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.

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.

Teachers' Perceptions of Their Work Environment in Swedish Junior High Schools

ERIC Educational Resources Information Center

Allodi, Mara Westling; Fischbein, Siv

2012-01-01

The aims of this study were to explore the organisational characteristics of junior high schools, to identify typologies of work environments and to explore the relationships between the type of work environment and how schools function. The educational profession and the role of teachers have been influenced by policies inspired by the principles…

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.

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.

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

Work performance evaluation and QoL of adults with High Functioning Autism Spectrum Disorders (HFASD).

PubMed

Katz, Noomi; Dejak, Ifat; Gal, Eynat

2015-01-01

Studies suggest that adults with High Functioning Autism Spectrum Disorders (HFASD) are reliant on others for support in functioning in everyday life and employment. This study followed a work placement program for people with HFASD over a nine months period. It aimed to measure the trajectory of their work performance and Quality of life on jobs in the open market. Twenty-six participants with HFASD ages 18-40 underwent extensive evaluation and based on it were placed in various jobs on the open market. Participants were followed for nine months at their work place at four different time points. QoL was self-assessed in addition to work performance (WPE) which was assessed both by first-hand and team member's accounts. Team members are health professional who accompany and support the participants in the transition to their jobs. All 26 participants were able to maintain their jobs during the nine months of follow-up. WPE was perceived as high to start with, and its scores slightly improved by both people with HFASD and team members. Self-report suggests a significant change in the quality of life of the participants, specifically in their evaluations of self-competency. This study enhances the importance of providing people with HFASD with work placing programs and following up during actual work performance.

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/

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…

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

Interaction of threat and verbal working memory in adolescents.

PubMed

Patel, Nilam; Vytal, Katherine; Pavletic, Nevia; Stoodley, Catherine; Pine, Daniel S; Grillon, Christian; Ernst, Monique

2016-04-01

Threat induces a state of sustained anxiety that can disrupt cognitive processing, and, reciprocally, cognitive processing can modulate an anxiety response to threat. These effects depend on the level of cognitive engagement, which itself varies as a function of task difficulty. In adults, we recently showed that induced anxiety impaired working memory accuracy at low and medium but not high load. Conversely, increasing the task load reduced the physiological correlates of anxiety (anxiety-potentiated startle). The present work examines such threat-cognition interactions as a function of age. We expected threat to more strongly impact working memory in younger individuals by virtue of putatively restricted cognitive resources and weaker emotion regulation. This was tested by examining the influence of age on the interaction of anxiety and working memory in 25 adolescents (10 to 17 years) and 25 adults (22 to 46 years). Working memory load was manipulated using a verbal n-back task. Anxiety was induced using the threat of an aversive loud scream and measured via eyeblink startle. Findings revealed that, in both age groups, accuracy was lower during threat than safe conditions at low and medium but not high load, and reaction times were faster during threat than safe conditions at high load but did not differ at other loads. Additionally, anxiety-potentiated startle was greater during low and medium than high load. Thus, the interactions of anxiety with working memory appear similar in adolescents and adults. Whether these similarities reflect common neural mechanisms would need to be assessed using functional neuroimaging. Published 2015. This article is a U.S. Government work and is in the public domain in the USA.

Post-retirement voluntary work and psychological functioning among older Chinese in Hong Kong.

PubMed

Wu, Anise M S; Tang, Catherine S K; Yan, Elsie C W

2005-03-01

This study examined demographic and psychosocial differences between older Chinese volunteers and non-volunteers. The influences of work-related factors on older Chinese volunteers' post-retirement psychological functioning and life satisfaction were also explored. A total of 501 older Chinese in Hong Kong were individually interviewed. About 65% of them were involved in community voluntary work since their retirement, with an average of four hours per week. Compared to those without voluntary work experiences, older Chinese volunteers had higher educational attainment and reported better physical health, higher self-efficacy, greater life satisfaction, and less psychological distress. Results from hierarchical regression analyses showed that salient correlates of a low level of psychological distress in older Chinese volunteers were high educational attainment, high self-efficacy, perceived good physical health, and high levels of perceived rewards and satisfaction from voluntary work. Self-efficacy and perceived rewards from voluntary work were also salient correlates of life satisfaction for older Chinese volunteers. As hypothesized, work-related factors of perceived rewards and work satisfaction remained significant correlates of older volunteers' psychological well-being, even after controlling for demographic and individual psychosocial factors. Limitations and implications of the study were also discussed.

Do Effort and Reward at Work Predict Changes in Cognitive Function? First Longitudinal Results from the Representative German Socio-Economic Panel

PubMed Central

Riedel, Natalie; Siegrist, Johannes; Wege, Natalia; Loerbroks, Adrian; Angerer, Peter; Li, Jian

2017-01-01

It has been suggested that work characteristics, such as mental demands, job control, and occupational complexity, are prospectively related to cognitive function. However, current evidence on links between psychosocial working conditions and cognitive change over time is inconsistent. In this study, we applied the effort–reward imbalance model that allows to build on previous research on mental demands and to introduce reward-based learning as a principle with beneficial effect on cognitive function. We aimed to investigate whether high effort, high reward, and low over-commitment in 2006 were associated with positive changes in cognitive function in terms of perceptual speed and word fluency (2006–2012), and whether the co-manifestation of high effort and high reward would yield the strongest association. To this end, we used data on 1031 employees who participated in a large and representative study. Multivariate linear regression analyses supported our main hypotheses (separate and combined effects of effort and reward), particularly on changes in perceptual speed, whereas the effects of over-commitment did not reach the level of statistical significance. Our findings extend available knowledge by examining the course of cognitive function over time. If corroborated by further evidence, organization-based measures in the workplace can enrich efforts towards preventing cognitive decline in ageing workforces. PMID:29140258

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.

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.

Work function determination of promising electrode materials for thermionic energy converters

NASA Technical Reports Server (NTRS)

Jacobson, D.; Storms, E.; Skaggs, B.; Kouts, T.; Jaskie, J.; Manda, M.

1976-01-01

The work function determinations of candidate materials for low temperature (1400 K) thermionics through vacuum emission tests are discussed. Two systems, a vacuum emission test vehicle and a thermionic emission microscope are used for emission measurements. Some nickel and cobalt based super alloys were preliminarily examined. High temperature physical properties and corrosion behavior of some super alloy candidates are presented. The corrosion behavior of sodium is of particular interest since topping cycles might use sodium heat transfer loops. A Marchuk tube was designed for plasma discharge studies with the carbide and possibly some super alloy samples. A series of metal carbides and other alloys were fabricated and tested in a special high temperature mass spectrometer. This information coupled with work function determinations was evaluated in an attempt to learn how electron bonding occurs in transition alloys.

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.

Transition to College and Students with High Functioning Autism Spectrum Disorder: Strategy Considerations for School Counselors

ERIC Educational Resources Information Center

Dipeolu, Abiola O.; Storlie, Cassandra; Johnson, Carol

2014-01-01

There are limited school counseling resources that address the unique post high school transition issues faced by students with High-functioning Autism Spectrum Disorder (HASD). While many school counselors have excellent skills in assessment, advising, and career planning, it is worthwhile to expand these to include working with students with…

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.

A low knee voltage and high breakdown voltage of 4H-SiC TSBS employing poly-Si/Ni Schottky scheme

NASA Astrophysics Data System (ADS)

Kim, Dong Young; Seok, Ogyun; Park, Himchan; Bahng, Wook; Kim, Hyoung Woo; Park, Ki Cheol

2018-02-01

We report a low knee voltage and high breakdown voltage 4H-SiC TSBS employing poly-Si/Ni dual Schottky contacts. A knee voltage was significantly improved from 0.75 to 0.48 V by utilizing an alternative low work-function material of poly-Si as an anode electrode. Also, reverse breakdown voltage was successfully improved from 901 to 1154 V due to a shrunk low-work-function Schottky region by a proposed self-align etching process between poly-Si and SiC. SiC TSBS with poly-Si/Ni dual Schottky scheme is a suitable structure for high-efficiency rectification and high-voltage blocking operation.

Boosting the power conversion efficiency of perovskite solar cells using self-organized polymeric hole extraction layers with high work function.

PubMed

Lim, Kyung-Geun; Kim, Hak-Beom; Jeong, Jaeki; Kim, Hobeom; Kim, Jin Young; Lee, Tae-Woo

2014-10-08

A self-organized hole extraction layer (SOHEL) with high work function (WF) is designed for energy level alignment with the ionization potential level of CH3 NH3 PbI3 . The SOHEL increases the built-in potential, photocurrent, and power conversion efficiency (PCE) of CH3 NH3 PbI3 perovskite solar cells. Thus, interface engineering of the positive electrode of solution-processed planar heterojunction solar cells using a high-WF SOHEL is a very effective way to achieve high device efficiency (PCE = 11.7% on glass). © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

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.

Dissociative tendencies and individual differences in high hypnotic suggestibility.

PubMed

Terhune, Devin Blair; Cardeña, Etzel; Lindgren, Magnus

2011-03-01

Inconsistencies in the relationship between dissociation and hypnosis may result from heterogeneity among highly suggestible individuals, in particular the existence of distinct highly suggestible subtypes that are of relevance to models of psychopathology and the consequences of trauma. This study contrasted highly suggestible subtypes high or low in dissociation on measures of hypnotic responding, cognitive functioning, and psychopathology. Twenty-one low suggestible (LS), 19 low dissociative highly suggestible (LDHS), and 11 high dissociative highly suggestible (HDHS) participants were administered hypnotic suggestibility scales and completed measures of free recall, working memory capacity, imagery, fantasy-proneness, psychopathology, and exposure to stressful life events. HDHS participants were more responsive to positive and negative hallucination suggestions and experienced greater involuntariness during hypnotic responding. They also exhibited impaired working memory capacity, elevated pathological fantasy and dissociative symptomatology, and a greater incidence of exposure to stressful life events. In contrast, LDHS participants displayed superior object visual imagery. These results provide further evidence for two highly suggestible subtypes: a dissociative subtype characterised by deficits in executive functioning and a predisposition to psychopathology, and a subtype that exhibits superior imagery and no observable deficits in functioning.

Employment activities and experiences of adults with high-functioning autism and Asperger’s Disorder.

PubMed

Baldwin, Susanna; Costley, Debra; Warren, Anthony

2014-10-01

There is limited large-scale empirical research into the working lives of adults who have an autism spectrum disorder with no co-occurring intellectual disability. Drawing on data from a national survey, this report describes the employment activities and experiences of 130 adults with Asperger's Disorder (AD) and high functioning autism (HFA) in Australia. Outcome measures include current occupation; occupational skill level and alignment with educational attainment; type of job contract; hours of work; support received to find work; support received in the workplace; and positive and negative experiences of employment. The findings confirm and expand upon existing evidence that adults with AD and HFA, despite their capacity and willingness to work, face significant disadvantages in the labour market and a lack of understanding and support in employment settings.

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.

Prognostic factors for duration of sickness absence due to musculoskeletal disorders.

PubMed

Lötters, Freek; Burdorf, Alex

2006-02-01

The purpose of this prospective cohort study with 1-year follow-up was to determine prognostic factors for duration of sickness absence due to musculoskeletal disorders. Workers were included when on sickness absence of 2 to 6 weeks due to musculoskeletal disorders. A self-administered questionnaire was used to collect personal and work-related factors, pain, functional disability, and general health perceptions. Statistical analysis was done with Cox proportional hazard regression with an interaction variable with time for every risk factor of interest. Univariate and multivariate analyses were performed on musculoskeletal disorders and, separately, for low back pain. The main factors that were associated with longer sickness absence were older age, gender, perceived physical workload, and poorer general health for neck, shoulder and upper extremity disorders, and functional disability, sciatica, worker's own perception of the ability of return to work, and chronic complaints for low back pain. Workers with a high perceived physical work load returned to work increasingly slower over time than expected, whereas workers with a high functional disability returned to work increasingly faster over time. High pain intensity is a major prognostic factor for duration of sickness absence, especially in low back pain. The different disease-specific risk profiles for prolonged sickness absence indicate that low back pain and upper extremity disorders need different approaches when applying intervention strategies with the aim of early return to work. The interaction of perceived physical workload with time suggests that perceived physical workload would increasingly hamper return to work and, hence, supports the need for workplace interventions among workers off work for prolonged periods.

White matter hyperintensities and cognitive reserve during a working memory task: a functional magnetic resonance imaging study in cognitively normal older adults.

PubMed

Fernández-Cabello, Sara; Valls-Pedret, Cinta; Schurz, Matthias; Vidal-Piñeiro, Dídac; Sala-Llonch, Roser; Bargallo, Nuria; Ros, Emilio; Bartrés-Faz, David

2016-12-01

Cognitive reserve (CR) models posit that lifestyle factors such as education modulate the relationship between brain damage and cognition. However, the functional correlates of CR in healthy aging are still under investigation. White matter hyperintensities (WMHs) are a common age-associated finding that impacts cognition. In this study, we used functional magnetic resonance imaging to characterize the patterns of brain activation during a working memory task in older participants with high and low levels of education (as a proxy of CR) and high and low WMH volumes. Ninety older volunteers (aged 63-76 years) and 16 young adults (aged 21-27) completed the study. We found that older adults with higher education had better working memory performance than their less educated peers. Among the highly educated participants, those with WMH over-recruited areas engaged by young volunteers and showed activation in additional cortical and subcortical structures. However, those with low WMH differed little with respect to their younger counterparts. Our findings demonstrate that the functional mechanisms subtending the effects of education, as a proxy of CR, are modulated according to the WMH burden. Copyright © 2016 Elsevier Inc. All rights reserved.

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.

An exploratory study of the effects of spatial working-memory load on prefrontal activation in low- and high-performing elderly.

PubMed

Vermeij, Anouk; van Beek, Arenda H E A; Reijs, Babette L R; Claassen, Jurgen A H R; Kessels, Roy P C

2014-01-01

Older adults show more bilateral prefrontal activation during cognitive performance than younger adults, who typically show unilateral activation. This over-recruitment has been interpreted as compensation for declining structure and function of the brain. Here we examined how the relationship between behavioral performance and prefrontal activation is modulated by different levels of working-memory load. Eighteen healthy older adults (70.8 ± 5.0 years; MMSE 29.3 ± 0.9) performed a spatial working-memory task (n-back). Oxygenated ([O2Hb]) and deoxygenated ([HHb]) hemoglobin concentration changes were registered by two functional Near-Infrared Spectroscopy (fNIRS) channels located over the left and right prefrontal cortex. Increased working-memory load resulted in worse performance compared to the control condition. [O2Hb] increased with rising working-memory load in both fNIRS channels. Based on the performance in the high working-memory load condition, the group was divided into low and high performers. A significant interaction effect of performance level and hemisphere on [O2Hb] increase was found, indicating that high performers were better able to keep the right prefrontal cortex engaged under high cognitive demand. Furthermore, in the low performers group, individuals with a larger decline in task performance from the control to the high working-memory load condition had a larger bilateral increase of [O2Hb]. The high performers did not show a correlation between performance decline and working-memory load related prefrontal activation changes. Thus, additional bilateral prefrontal activation in low performers did not necessarily result in better cognitive performance. Our study showed that bilateral prefrontal activation may not always be successfully compensatory. Individual behavioral performance should be taken into account to be able to distinguish successful and unsuccessful compensation or declined neural efficiency.

Impact of bimetal electrodes on dielectric properties of TiO2 and Al-doped TiO2 films.

PubMed

Kim, Seong Keun; Han, Sora; Jeon, Woojin; Yoon, Jung Ho; Han, Jeong Hwan; Lee, Woongkyu; Hwang, Cheol Seong

2012-09-26

Rutile structured Al-doped TiO(2) (ATO) and TiO(2) films were grown on bimetal electrodes (thin Ru/thick TiN, Pt, and Ir) for high-performance capacitors. The work function of the top Ru layer decreased on TiN and increased on Pt and Ir when it was thinner than ~2 nm, suggesting that the lower metal within the electrodes influences the work function of the very thin Ru layer. The use of the lower electrode with a high work function for bottom electrode eventually improves the leakage current properties of the capacitor at a very thin Ru top layer (≤2 nm) because of the increased Schottky barrier height at the interface between the dielectric and the bottom electrode. The thin Ru layer was necessary to achieve the rutile structured ATO and TiO(2) dielectric films.

Unimpaired Perception of Social and Physical Causality, but Impaired Perception of Animacy in High Functioning Children with Autism

ERIC Educational Resources Information Center

Congiu, Sara; Schlottmann, Anne; Ray, Elizabeth

2010-01-01

We investigated perception of social and physical causality and animacy in simple motion events, for high-functioning children with autism (CA = 13, VMA = 9.6). Children matched 14 different animations to pictures showing physical, social or non-causality. In contrast to previous work, children with autism performed at a high level similar to…

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…

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.

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.

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.

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.

A functional polymorphism of the MAOA gene is associated with neural responses to induced anger control.

PubMed

Denson, Thomas F; Dobson-Stone, Carol; Ronay, Richard; von Hippel, William; Schira, Mark M

2014-07-01

Aggressiveness is highly heritable. Recent experimental work has linked individual differences in a functional polymorphism of the monoamine oxidase-A gene (MAOA) to anger-driven aggression. Other work has implicated the dorsal ACC (dACC) in cognitive-emotional control and the amygdala in emotional arousal. The present imaging genetics study investigated dACC and amygdala reactivity to induced anger control as a function of MAOA genotype. A research assistant asked 38 healthy male undergraduates to control their anger in response to an insult by a rude experimenter. Men with the low-expression allele showed increased dACC and amygdala activation after the insult, but men with the high-expression allele did not. Both dACC and amygdala activation independently mediated the relationship between MAOA genotype and self-reported anger control. Moreover, following the insult, men with the high-functioning allele showed functional decoupling between the amygdala and dACC, but men with the low-functioning allele did not. These results suggest that heightened dACC and amygdala activation and their connectivity are neuroaffective mechanisms underlying anger control in participants with the low-functioning allele of the MAOA gene.

Executive Functioning in Highly Talented Soccer Players

PubMed Central

Verburgh, Lot; Scherder, Erik J. A.; van Lange, Paul A.M.; Oosterlaan, Jaap

2014-01-01

Executive functions might be important for successful performance in sports, particularly in team sports requiring quick anticipation and adaptation to continuously changing situations in the field. The executive functions motor inhibition, attention and visuospatial working memory were examined in highly talented soccer players. Eighty-four highly talented youth soccer players (mean age 11.9), and forty-two age-matched amateur soccer players (mean age 11.8) in the age range 8 to 16 years performed a Stop Signal task (motor inhibition), the Attention Network Test (alerting, orienting, and executive attention) and a visuospatial working memory task. The highly talented soccer players followed the talent development program of the youth academy of a professional soccer club and played at the highest national soccer competition for their age. The amateur soccer players played at a regular soccer club in the same geographical region as the highly talented soccer players and play in a regular regional soccer competition. Group differences were tested using analyses of variance. The highly talented group showed superior motor inhibition as measured by stop signal reaction time (SSRT) on the Stop Signal task and a larger alerting effect on the Attention Network Test, indicating an enhanced ability to attain and maintain an alert state. No group differences were found for orienting and executive attention and visuospatial working memory. A logistic regression model with group (highly talented or amateur) as dependent variable and executive function measures that significantly distinguished between groups as predictors showed that these measures differentiated highly talented soccer players from amateur soccer players with 89% accuracy. Highly talented youth soccer players outperform youth amateur players on suppressing ongoing motor responses and on the ability to attain and maintain an alert state; both may be essential for success in soccer. PMID:24632735

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.

In Search of Joy in Practice: A Report of 23 High-Functioning Primary Care Practices

PubMed Central

Sinsky, Christine A.; Willard-Grace, Rachel; Schutzbank, Andrew M.; Sinsky, Thomas A.; Margolius, David; Bodenheimer, Thomas

2013-01-01

We highlight primary care innovations gathered from high-functioning primary care practices, innovations we believe can facilitate joy in practice and mitigate physician burnout. To do so, we made site visits to 23 high-performing primary care practices and focused on how these practices distribute functions among the team, use technology to their advantage, improve outcomes with data, and make the job of primary care feasible and enjoyable as a life’s vocation. Innovations identified include (1) proactive planned care, with previsit planning and previsit laboratory tests; (2) sharing clinical care among a team, with expanded rooming protocols, standing orders, and panel management; (3) sharing clerical tasks with collaborative documentation (scribing), nonphysician order entry, and streamlined prescription management; (4) improving communication by verbal messaging and in-box management; and (5) improving team functioning through co-location, team meetings, and work flow mapping. Our observations suggest that a shift from a physician-centric model of work distribution and responsibility to a shared-care model, with a higher level of clinical support staff per physician and frequent forums for communication, can result in high-functioning teams, improved professional satisfaction, and greater joy in practice. PMID:23690328

Comparing current definitions of return to work: a measurement approach.

PubMed

Steenstra, I A; Lee, H; de Vroome, E M M; Busse, J W; Hogg-Johnson, S J

2012-09-01

Return-to-work (RTW) status is an often used outcome in work and health research. In low back pain, work is regarded as a normal activity a worker should return to in order to fully recover. Comparing outcomes across studies and even jurisdictions using different definitions of RTW can be challenging for readers in general and when performing a systematic review in particular. In this study, the measurement properties of previously defined RTW outcomes were examined with data from two studies from two countries. Data on RTW in low back pain (LBP) from the Canadian Early Claimant Cohort (ECC); a workers' compensation based study, and the Dutch Amsterdam Sherbrooke Evaluation (ASE) study were analyzed. Correlations between outcomes, differences in predictive validity when using different outcomes and construct validity when comparing outcomes to a functional status outcome were analyzed. In the ECC all definitions were highly correlated and performed similarly in predictive validity. When compared to functional status, RTW definitions in the ECC study performed fair to good on all time points. In the ASE study all definitions were highly correlated and performed similarly in predictive validity. The RTW definitions, however, failed to compare or compared poorly with functional status. Only one definition compared fairly on one time point. Differently defined outcomes are highly correlated, give similar results in prediction, but seem to differ in construct validity when compared to functional status depending on societal context or possibly birth cohort. Comparison of studies using different RTW definitions appears valid as long as RTW status is not considered as a measure of functional status.

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.

WISC-IV and WIAT-II Profiles in Children with High-Functioning Autism

ERIC Educational Resources Information Center

Mayes, Susan Dickerson; Calhoun, Susan L.

2008-01-01

Children with high-functioning autism earned above normal scores on the Wechsler Intelligence Scale for Children-Fourth Edition (WISC-IV) Perceptual Reasoning and Verbal Comprehension Indexes and below normal scores on the Working Memory and Processing Speed Indexes and Wechsler Individual Achievement Test-Second Edition (WIAT-II) Written…

Effects of Functional Groups in Redox-Active Organic Molecules: A High-Throughput Screening Approach

DOE PAGES

Pelzer, Kenley M.; Cheng, Lei; Curtiss, Larry A.

2016-12-08

Nonaqueous redox flow batteries have attracted recent attention with their potential for high electrochemical storage capacity, with organic electrolytes serving as solvents with a wide electrochemical stability window. Organic molecules can also serve as electroactive species, where molecules with low reduction potentials or high oxidation potentials can provide substantial chemical energy. To identify promising electrolytes in a vast chemical space, high-throughput screening (HTS) of candidate molecules plays an important role, where HTS is used to calculate properties of thousands of molecules and identify a few organic molecules worthy of further attention in battery research. Here, in this work, we presentmore » reduction and oxidation potentials obtained from HTS of 4178 molecules. The molecules are composed of base groups of five- or six-membered rings with one or two functional groups attached, with the set of possible functional groups including both electron-withdrawing and electron-donating groups. In addition to observing the trends in potentials that result from differences in organic base groups and functional groups, we analyze the effects of molecular characteristics such as multiple bonds, Hammett parameters, and functional group position. In conclusion, this work provides useful guidance in determining how the identities of the base groups and functional groups are correlated with desirable reduction and oxidation potentials.« less

Effects of Functional Groups in Redox-Active Organic Molecules: A High-Throughput Screening Approach

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

Pelzer, Kenley M.; Cheng, Lei; Curtiss, Larry A.

Nonaqueous redox flow batteries have attracted recent attention with their potential for high electrochemical storage capacity, with organic electrolytes serving as solvents with a wide electrochemical stability window. Organic molecules can also serve as electroactive species, where molecules with low reduction potentials or high oxidation potentials can provide substantial chemical energy. To identify promising electrolytes in a vast chemical space, high-throughput screening (HTS) of candidate molecules plays an important role, where HTS is used to calculate properties of thousands of molecules and identify a few organic molecules worthy of further attention in battery research. Here, in this work, we presentmore » reduction and oxidation potentials obtained from HTS of 4178 molecules. The molecules are composed of base groups of five- or six-membered rings with one or two functional groups attached, with the set of possible functional groups including both electron-withdrawing and electron-donating groups. In addition to observing the trends in potentials that result from differences in organic base groups and functional groups, we analyze the effects of molecular characteristics such as multiple bonds, Hammett parameters, and functional group position. In conclusion, this work provides useful guidance in determining how the identities of the base groups and functional groups are correlated with desirable reduction and oxidation potentials.« less

Transparent amorphous oxide semiconductors for organic electronics: Application to inverted OLEDs

PubMed Central

Hosono, Hideo; Toda, Yoshitake; Kamiya, Toshio; Watanabe, Satoru

2017-01-01

Efficient electron transfer between a cathode and an active organic layer is one key to realizing high-performance organic devices, which require electron injection/transport materials with very low work functions. We developed two wide-bandgap amorphous (a-) oxide semiconductors, a-calcium aluminate electride (a-C12A7:e) and a-zinc silicate (a-ZSO). A-ZSO exhibits a low work function of 3.5 eV and high electron mobility of 1 cm2/(V · s); furthermore, it also forms an ohmic contact with not only conventional cathode materials but also anode materials. A-C12A7:e has an exceptionally low work function of 3.0 eV and is used to enhance the electron injection property from a-ZSO to an emission layer. The inverted electron-only and organic light-emitting diode (OLED) devices fabricated with these two materials exhibit excellent performance compared with the normal type with LiF/Al. This approach provides a solution to the problem of fabricating oxide thin-film transistor-driven OLEDs with both large size and high stability. PMID:28028243

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.

NIR spectroscopic investigation of m. vastus lateralis in patients with mitochondrial myopathies as detected by respirometric investigation of mitochondrial function in skinned fibers

NASA Astrophysics Data System (ADS)

Gellerich, Frank N.; Mueller, Tobias; Nioka, Shoko; Hertel, Katrin; Schulte-Mattler, Wilhelm J.; Zierz, Stephan; Chance, Britton

1998-01-01

Noninvasive measurement of changes in oxygenation of human skeletal muscle can be done with a dual-wavelength near infrared (NIR) spectrophotometer. This allows a noninvasive investigation of muscle mitochondria. An exercise protocol was developed to study the load dependent changes in oxygenation of m. vastus lateralis of myopathic patients. On a bicycle ergometer exercise was done periodically. One period consisted of 1.5 min exercise followed by 3 min rest. Work load in the first period was 20 W, and was increased by 10 W for each subsequent period until maximal work load was reached. In 12 healthy volunteers we observed oxygenation of muscle during periods of low work load (warm-up effect). During periods of high work load the muscle deoxygenated. The work load at transition from oxygenation to deoxygenation (deoxygenation threshold) in controls was 75 W. In 3 patients with myopathies, in addition to NIR- spectroscopy, function of mitochondria of specimen of m. vastus lateralis was investigated biochemically. Muscle fibers were skinned with saponin and investigated with high resolution respirometry and multiple substrate-inhibitor- titration. Mitochondrial function was impaired in patients who had abnormal findings in NIR spectroscopy.

NIR spectroscopic investigation of m. vastus lateralis in patients with mitochondrial myopathies as detected by respirometric investigation of mitochondrial function in skinned fibers

NASA Astrophysics Data System (ADS)

Gellerich, Frank N.; Mueller, Tobias; Nioka, Shoko; Hertel, Katrin; Schulte-Mattler, Wilhelm J.; Zierz, Stephan; Chance, Britton

1997-12-01

Noninvasive measurement of changes in oxygenation of human skeletal muscle can be done with a dual-wavelength near infrared (NIR) spectrophotometer. This allows a noninvasive investigation of muscle mitochondria. An exercise protocol was developed to study the load dependent changes in oxygenation of m. vastus lateralis of myopathic patients. On a bicycle ergometer exercise was done periodically. One period consisted of 1.5 min exercise followed by 3 min rest. Work load in the first period was 20 W, and was increased by 10 W for each subsequent period until maximal work load was reached. In 12 healthy volunteers we observed oxygenation of muscle during periods of low work load (warm-up effect). During periods of high work load the muscle deoxygenated. The work load at transition from oxygenation to deoxygenation (deoxygenation threshold) in controls was 75 W. In 3 patients with myopathies, in addition to NIR- spectroscopy, function of mitochondria of specimen of m. vastus lateralis was investigated biochemically. Muscle fibers were skinned with saponin and investigated with high resolution respirometry and multiple substrate-inhibitor- titration. Mitochondrial function was impaired in patients who had abnormal findings in NIR spectroscopy.

The Quest for Ordinary Lives: The Integrated Post-School Vocational Functioning of 50 Workers with Significant Disabilities

ERIC Educational Resources Information Center

Brown, Lou; Shiraga, Betsy; Kessler, Kim

2006-01-01

An extensive report is made of the work histories of 50 adults with significant disabilities who are served by Community Work Services, Inc., in Madison, Wisconsin. The primary purpose is to share information about the integrated vocational functioning of these adults, 90% of whom exited high school 15-24 years ago. A second purpose is to…

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

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

Work disability remains a major problem in rheumatoid arthritis in the 2000s: data from 32 countries in the QUEST-RA study.

PubMed

Sokka, Tuulikki; Kautiainen, Hannu; Pincus, Theodore; Verstappen, Suzanne M M; Aggarwal, Amita; Alten, Rieke; Andersone, Daina; Badsha, Humeira; Baecklund, Eva; Belmonte, Miguel; Craig-Müller, Jürgen; da Mota, Licia Maria Henrique; Dimic, Alexander; Fathi, Nihal A; Ferraccioli, Gianfranco; Fukuda, Wataru; Géher, Pál; Gogus, Feride; Hajjaj-Hassouni, Najia; Hamoud, Hisham; Haugeberg, Glenn; Henrohn, Dan; Horslev-Petersen, Kim; Ionescu, Ruxandra; Karateew, Dmitry; Kuuse, Reet; Laurindo, Ieda Maria Magalhaes; Lazovskis, Juris; Luukkainen, Reijo; Mofti, Ayman; Murphy, Eithne; Nakajima, Ayako; Oyoo, Omondi; Pandya, Sapan C; Pohl, Christof; Predeteanu, Denisa; Rexhepi, Mjellma; Rexhepi, Sylejman; Sharma, Banwari; Shono, Eisuke; Sibilia, Jean; Sierakowski, Stanislaw; Skopouli, Fotini N; Stropuviene, Sigita; Toloza, Sergio; Valter, Ivo; Woolf, Anthony; Yamanaka, Hisashi

2010-01-01

Work disability is a major consequence of rheumatoid arthritis (RA), associated not only with traditional disease activity variables, but also more significantly with demographic, functional, occupational, and societal variables. Recent reports suggest that the use of biologic agents offers potential for reduced work disability rates, but the conclusions are based on surrogate disease activity measures derived from studies primarily from Western countries. The Quantitative Standard Monitoring of Patients with RA (QUEST-RA) multinational database of 8,039 patients in 86 sites in 32 countries, 16 with high gross domestic product (GDP) (>24K US dollars (USD) per capita) and 16 low-GDP countries (<11K USD), was analyzed for work and disability status at onset and over the course of RA and clinical status of patients who continued working or had stopped working in high-GDP versus low-GDP countries according to all RA Core Data Set measures. Associations of work disability status with RA Core Data Set variables and indices were analyzed using descriptive statistics and regression analyses. At the time of first symptoms, 86% of men (range 57%-100% among countries) and 64% (19%-87%) of women <65 years were working. More than one third (37%) of these patients reported subsequent work disability because of RA. Among 1,756 patients whose symptoms had begun during the 2000s, the probabilities of continuing to work were 80% (95% confidence interval (CI) 78%-82%) at 2 years and 68% (95% CI 65%-71%) at 5 years, with similar patterns in high-GDP and low-GDP countries. Patients who continued working versus stopped working had significantly better clinical status for all clinical status measures and patient self-report scores, with similar patterns in high-GDP and low-GDP countries. However, patients who had stopped working in high-GDP countries had better clinical status than patients who continued working in low-GDP countries. The most significant identifier of work disability in all subgroups was Health Assessment Questionnaire (HAQ) functional disability score. Work disability rates remain high among people with RA during this millennium. In low-GDP countries, people remain working with high levels of disability and disease activity. Cultural and economic differences between societies affect work disability as an outcome measure for RA.

Work disability remains a major problem in rheumatoid arthritis in the 2000s: data from 32 countries in the QUEST-RA Study

PubMed Central

2010-01-01

Introduction Work disability is a major consequence of rheumatoid arthritis (RA), associated not only with traditional disease activity variables, but also more significantly with demographic, functional, occupational, and societal variables. Recent reports suggest that the use of biologic agents offers potential for reduced work disability rates, but the conclusions are based on surrogate disease activity measures derived from studies primarily from Western countries. Methods The Quantitative Standard Monitoring of Patients with RA (QUEST-RA) multinational database of 8,039 patients in 86 sites in 32 countries, 16 with high gross domestic product (GDP) (>24K US dollars (USD) per capita) and 16 low-GDP countries (<11K USD), was analyzed for work and disability status at onset and over the course of RA and clinical status of patients who continued working or had stopped working in high-GDP versus low-GDP countries according to all RA Core Data Set measures. Associations of work disability status with RA Core Data Set variables and indices were analyzed using descriptive statistics and regression analyses. Results At the time of first symptoms, 86% of men (range 57%-100% among countries) and 64% (19%-87%) of women <65 years were working. More than one third (37%) of these patients reported subsequent work disability because of RA. Among 1,756 patients whose symptoms had begun during the 2000s, the probabilities of continuing to work were 80% (95% confidence interval (CI) 78%-82%) at 2 years and 68% (95% CI 65%-71%) at 5 years, with similar patterns in high-GDP and low-GDP countries. Patients who continued working versus stopped working had significantly better clinical status for all clinical status measures and patient self-report scores, with similar patterns in high-GDP and low-GDP countries. However, patients who had stopped working in high-GDP countries had better clinical status than patients who continued working in low-GDP countries. The most significant identifier of work disability in all subgroups was Health Assessment Questionnaire (HAQ) functional disability score. Conclusions Work disability rates remain high among people with RA during this millennium. In low-GDP countries, people remain working with high levels of disability and disease activity. Cultural and economic differences between societies affect work disability as an outcome measure for RA. PMID:20226018

Functional Analysis in Long-Term Operation of High Power UV-LEDs in Continuous Fluoro-Sensing Systems for Hydrocarbon Pollution

PubMed Central

Arques-Orobon, Francisco Jose; Nuñez, Neftali; Vazquez, Manuel; Gonzalez-Posadas, Vicente

2016-01-01

This work analyzes the long-term functionality of HP (High-power) UV-LEDs (Ultraviolet Light Emitting Diodes) as the exciting light source in non-contact, continuous 24/7 real-time fluoro-sensing pollutant identification in inland water. Fluorescence is an effective alternative in the detection and identification of hydrocarbons. The HP UV-LEDs are more advantageous than classical light sources (xenon and mercury lamps) and helps in the development of a low cost, non-contact, and compact system for continuous real-time fieldwork. This work analyzes the wavelength, output optical power, and the effects of viscosity, temperature of the water pollutants, and the functional consistency for long-term HP UV-LED working operation. To accomplish the latter, an analysis of the influence of two types 365 nm HP UV-LEDs degradation under two continuous real-system working mode conditions was done, by temperature Accelerated Life Tests (ALTs). These tests estimate the mean life under continuous working conditions of 6200 h and for cycled working conditions (30 s ON & 30 s OFF) of 66,000 h, over 7 years of 24/7 operating life of hydrocarbon pollution monitoring. In addition, the durability in the face of the internal and external parameter system variations is evaluated. PMID:26927113

Functional Analysis in Long-Term Operation of High Power UV-LEDs in Continuous Fluoro-Sensing Systems for Hydrocarbon Pollution.

PubMed

Arques-Orobon, Francisco Jose; Nuñez, Neftali; Vazquez, Manuel; Gonzalez-Posadas, Vicente

2016-02-26

This work analyzes the long-term functionality of HP (High-power) UV-LEDs (Ultraviolet Light Emitting Diodes) as the exciting light source in non-contact, continuous 24/7 real-time fluoro-sensing pollutant identification in inland water. Fluorescence is an effective alternative in the detection and identification of hydrocarbons. The HP UV-LEDs are more advantageous than classical light sources (xenon and mercury lamps) and helps in the development of a low cost, non-contact, and compact system for continuous real-time fieldwork. This work analyzes the wavelength, output optical power, and the effects of viscosity, temperature of the water pollutants, and the functional consistency for long-term HP UV-LED working operation. To accomplish the latter, an analysis of the influence of two types 365 nm HP UV-LEDs degradation under two continuous real-system working mode conditions was done, by temperature Accelerated Life Tests (ALTs). These tests estimate the mean life under continuous working conditions of 6200 h and for cycled working conditions (30 s ON & 30 s OFF) of 66,000 h, over 7 years of 24/7 operating life of hydrocarbon pollution monitoring. In addition, the durability in the face of the internal and external parameter system variations is evaluated.

‘Activity-silent’ working memory in prefrontal cortex: a dynamic coding framework

PubMed Central

Stokes, Mark G.

2015-01-01

Working memory (WM) provides the functional backbone to high-level cognition. Maintenance in WM is often assumed to depend on the stationary persistence of neural activity patterns that represent memory content. However, accumulating evidence suggests that persistent delay activity does not always accompany WM maintenance but instead seems to wax and wane as a function of the current task relevance of memoranda. Furthermore, new methods for measuring and analysing population-level patterns show that activity states are highly dynamic. At first glance, these dynamics seem at odds with the very nature of WM. How can we keep a stable thought in mind while brain activity is constantly changing? This review considers how neural dynamics might be functionally important for WM maintenance. PMID:26051384

Changes in cognitive functions of students in the transitional period from elementary school to junior high school.

PubMed

Mizuno, Kei; Tanaka, Masaaki; Fukuda, Sanae; Sasabe, Tetsuya; Imai-Matsumura, Kyoko; Watanabe, Yasuyoshi

2011-05-01

When students proceed to junior high school from elementary school, rapid changes in the environment occur, which may cause various behavioral and emotional problems. However, the changes in cognitive functions during this transitional period have rarely been studied. In 158 elementary school students from 4th- to 6th-grades and 159 junior high school students from 7th- to 9th-grades, we assessed various cognitive functions, including motor processing, spatial construction ability, semantic fluency, immediate memory, delayed memory, spatial and non-spatial working memory, and selective, alternative, and divided attention. Our findings showed that performance on spatial and non-spatial working memory, alternative attention, divided attention, and semantic fluency tasks improved from elementary to junior high school. In particular, performance on alternative and divided attention tasks improved during the transitional period from elementary to junior high school. Our finding suggests that development of alternative and divided attention is of crucial importance in the transitional period from elementary to junior high school. Copyright © 2010 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved.

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

PubMed

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

2014-05-01

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

Working Memory and Intelligence Are Highly Related Constructs, but Why?

ERIC Educational Resources Information Center

Colom, Roberto; Abad, Francisco J.; Quiroga, M. Angeles; Shih, Pei Chun; Flores-Mendoza, Carmen

2008-01-01

Working memory and the general factor of intelligence (g) are highly related constructs. However, we still don't know why. Some models support the central role of simple short-term storage, whereas others appeal to executive functions like the control of attention. Nevertheless, the available empirical evidence does not suffice to get an answer,…

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.

[Relationship between the frequency of work-related stress and prevalence of functional dyspepsia in Lima Geriatric Army Hospital].

PubMed

Valenzuela Narváez, Daniel Raúl; Gayoso Cervantes, Milagros

2017-01-01

To determine the relationship between the frequency of work-related stress and prevalence of functional dyspepsia in a sample of 218 military older 50 years in 2010 in Lima Military Hospital Geriatric. Descriptive and explanatory study and for the data collection on stress, were used the Vital Events Scale Holmes-Rahe and clinical records for clinical and upper endoscopy registration that comply the criteria of Rome III for functional dyspepsia. For processing and data analysis the statistical software package SPSS (Statistical Package for Social Sciences) was used. 100% of military showed some level of work stress during the study year; thus, 36.7% had a high level, 31.2% medium or moderate level, and 32.1% had low stress level; these percentages medium and high stress levels accounted for 67.9%. These results establish that job stress is a common discomfort in the study population (tabulated Chi2 = 3.841, chi2 observed = 27,908). Regarding functional dyspepsia prevalence of 37.2%, which indicates that it is a common condition in those military (tabular Z = 1.96, Z c = 9.163) it was determined. There is a significant relationship between the frequency of work-related stress and prevalence of functional dyspepsia in military activity in older than 50 years (tabulated Chi2 = 5.991, chi2 observed = 28,878, contingency coefficient = 0.342).

FMRI of visual working memory in high school football players.

PubMed

Shenk, Trey E; Robinson, Meghan E; Svaldi, Diana O; Abbas, Kausar; Breedlove, Katherine M; Leverenz, Larry J; Nauman, Eric A; Talavage, Thomas M

2015-01-01

Visual working memory deficits have been observed in at-risk athletes. This study uses a visual N-back working memory functional magnetic resonance imaging task to longitudinally assess asymptomatic football athletes for abnormal activity. Athletes were increasingly "flagged" as the season progressed. Flagging may provide early detection of injury.

On thermophysical effects on the surface of functional nanostructured materials obtained with the application of femtosecond laser pulses

NASA Astrophysics Data System (ADS)

Babenko, D. D.; Dmitriev, A. S.; Makarov, P. G.; Mikhailova, I. A.

2017-11-01

In recent years, a great scientific and practical interest is caused by functional energy surfaces, modified for certain technological problems. The urgency of the work is to develop promising technologies for thermal and nuclear power engineering, methods for converting solar energy, cooling low-current and high-current electronics devices, energy storage and transport systems on the basis of studying and developing new ways of creating and modifying the functional surfaces of heat exchange and other devices. Modified functional surfaces must have a number of new mechanical and thermophysical properties, including mechanical strength, a new surface morphology for controlling the processes of wetting and spreading working fluids on them, and have high efficiency from the viewpoint of thermohydrodynamic processes of flow and heat and mass transfer of working fluids to them. Among the various ways of modifying surfaces, recently, the method of surface exposure to femtosecond laser pulses (FLI) has become widespread. The technology of femtosecond laser surface treatment (FLPO) of solid materials has shown high efficiency, reliability, high productivity and a huge variety of modification methods. The paper presents new results on the study of thermophysical phenomena - the wetting and spreading of drops of various liquids, the study of the hysteresis of the contact angle, the study of evaporation and boiling processes on functional energy surfaces modified by femtosecond laser pulses. It is shown that in the majority of cases the presence of regular or stochastic nanostructures on the surface leads to a very strong change in the basic properties of the surface, which makes it possible to use such a technology to quickly and efficiently modify and obtain functional energy surfaces for certain predetermined purposes.

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.

Associations of work characteristics, employee strain and self-perceived quality of care in Emergency Departments: A cross-sectional study.

PubMed

Weigl, Matthias; Schneider, Anna

2017-01-01

The individual and shared effects of adverse work characteristics on patient care in Emergency Departments (ED) are yet not well understood. We investigated the associations of self-reported ED work characteristics, work-related strain, and perceived quality of care. Questionnaire-based survey with standardized measures among N=53 ED professionals (i.e., nurses, physicians, and administration staff). The study was conducted in the interdisciplinary ED of a German community hospital. A high prevalence of work-related strain was observed: 66.0% of ED professionals showed high levels of emotional exhaustion and 55.6% showed irritation scores above the cut-off value. ED staff reported high supervisor support and autonomy, paired with high time pressure and patient-related stressors. Multivariate analyses revealed that high time pressure and low supervisor support were associated with high work-related strain. Low staffing was related to inferior quality of ED care. ED work systems involve high competing demands for ED professionals with substantial risks for work-related strain. Moreover, adverse ED work characteristics comprise risks for high quality patient care. Our results suggest that promoting work characteristics might foster ED staff functioning on the job as well as improve ED patient care. Copyright © 2016 Elsevier Ltd. All rights reserved.

Employment Activities and Experiences of Adults with High-Functioning Autism and Asperger's Disorder

ERIC Educational Resources Information Center

Baldwin, Susanna; Costley, Debra; Warren, Anthony

2014-01-01

There is limited large-scale empirical research into the working lives of adults who have an autism spectrum disorder with no co-occurring intellectual disability. Drawing on data from a national survey, this report describes the employment activities and experiences of 130 adults with Asperger's Disorder (AD) and high functioning autism (HFA) in…

How Stimulus and Task Complexity Affect Monitoring in High-Functioning Adults with Autism Spectrum Disorder

ERIC Educational Resources Information Center

Koolen, Sophieke; Vissers, Constance Th. W. M.; Egger, Jos I. M.; Verhoeven, Ludo

2014-01-01

The present study examined whether individuals with autism spectrum disorder (ASD) are able to update and monitor working memory representations of visual input, and whether performance is influenced by stimulus and task complexity. 15 high-functioning adults with ASD and 15 controls were asked to allocate either elements of abstract figures or…

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.

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.

Graded recombination layers for multijunction photovoltaics.

PubMed

Koleilat, Ghada I; Wang, Xihua; Sargent, Edward H

2012-06-13

Multijunction devices consist of a stack of semiconductor junctions having bandgaps tuned across a broad spectrum. In solar cells this concept is used to increase the efficiency of photovoltaic harvesting, while light emitters and detectors use it to achieve multicolor and spectrally tunable behavior. In series-connected current-matched multijunction devices, the recombination layers must allow the hole current from one cell to recombine, with high efficiency and low voltage loss, with the electron current from the next cell. We recently reported a tandem solar cell in which the recombination layer was implemented using a progression of n-type oxides whose doping densities and work functions serve to connect, with negligible resistive loss at solar current densities, the constituent cells. Here we present the generalized conditions for design of efficient graded recombination layer solar devices. We report the number of interlayers and the requirements on work function and doping of each interlayer, to bridge an work function difference as high as 1.6 eV. We also find solutions that minimize the doping required of the interlayers in order to minimize optical absorption due to free carriers in the graded recombination layer (GRL). We demonstrate a family of new GRL designs experimentally and highlight the benefits of the progression of dopings and work functions in the interlayers.

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.

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.

Transparent Carbon Nanotube layers as cathodes in OLEDs

NASA Astrophysics Data System (ADS)

Papadimitratos, Alexios; Nasibulin, Albert; Kauppinen, Esko; Zakhidov, Anvar; Solarno Inc Collaboration; Aalto University Collaboration; UT Dallas Collaboration

2011-03-01

Organic Light Emitting diodes (OLEDs) have attracted high interest in recent years due to their potential use in future lighting and display applications. Reported work on OLEDs traditionally utilizes low work function materials as cathodes that are expensive to fabricate because of the high vacuum processing. Transparent carbon nanotube (CNT) sheets have excellent mechanical and electrical properties. We have already shown earlier that multi-wall (MWCNT) as well as single CNT (SWCNT) sheets can be used as effective anodes in bright OLEDs [,]. The true advantage of using the CNT sheets lies in flexible devices and new architectures with CNT sheet as layers in tandem devices with parallel connection. In this work, we are investigating the possibility of using SWCNT as cathodes in OLEDs. SWCNT sheets have been reported to show lower work function compared to MWCNT. Our work attempts to demonstrate transparent OLED devices with CNT anodes and cathodes. In the process, OLEDs with CNT cathodes have been fabricated in normal and inverted configurations using inorganic oxides (MoO3,ZnO) as invertion layers.

Brain and effort: brain activation and effort-related working memory in healthy participants and patients with working memory deficits.

PubMed

Engström, Maria; Landtblom, Anne-Marie; Karlsson, Thomas

2013-01-01

Despite the interest in the neuroimaging of working memory, little is still known about the neurobiology of complex working memory in tasks that require simultaneous manipulation and storage of information. In addition to the central executive network, we assumed that the recently described salience network [involving the anterior insular cortex (AIC) and the anterior cingulate cortex (ACC)] might be of particular importance to working memory tasks that require complex, effortful processing. Healthy participants (n = 26) and participants suffering from working memory problems related to the Kleine-Levin syndrome (KLS) (a specific form of periodic idiopathic hypersomnia; n = 18) participated in the study. Participants were further divided into a high- and low-capacity group, according to performance on a working memory task (listening span). In a functional magnetic resonance imaging (fMRI) study, participants were administered the reading span complex working memory task tapping cognitive effort. The fMRI-derived blood oxygen level dependent (BOLD) signal was modulated by (1) effort in both the central executive and the salience network and (2) capacity in the salience network in that high performers evidenced a weaker BOLD signal than low performers. In the salience network there was a dichotomy between the left and the right hemisphere; the right hemisphere elicited a steeper increase of the BOLD signal as a function of increasing effort. There was also a stronger functional connectivity within the central executive network because of increased task difficulty. The ability to allocate cognitive effort in complex working memory is contingent upon focused resources in the executive and in particular the salience network. Individual capacity during the complex working memory task is related to activity in the salience (but not the executive) network so that high-capacity participants evidence a lower signal and possibly hence a larger dynamic response.

Brain and effort: brain activation and effort-related working memory in healthy participants and patients with working memory deficits

PubMed Central

Engström, Maria; Landtblom, Anne-Marie; Karlsson, Thomas

2013-01-01

Despite the interest in the neuroimaging of working memory, little is still known about the neurobiology of complex working memory in tasks that require simultaneous manipulation and storage of information. In addition to the central executive network, we assumed that the recently described salience network [involving the anterior insular cortex (AIC) and the anterior cingulate cortex (ACC)] might be of particular importance to working memory tasks that require complex, effortful processing. Method: Healthy participants (n = 26) and participants suffering from working memory problems related to the Kleine–Levin syndrome (KLS) (a specific form of periodic idiopathic hypersomnia; n = 18) participated in the study. Participants were further divided into a high- and low-capacity group, according to performance on a working memory task (listening span). In a functional magnetic resonance imaging (fMRI) study, participants were administered the reading span complex working memory task tapping cognitive effort. Principal findings: The fMRI-derived blood oxygen level dependent (BOLD) signal was modulated by (1) effort in both the central executive and the salience network and (2) capacity in the salience network in that high performers evidenced a weaker BOLD signal than low performers. In the salience network there was a dichotomy between the left and the right hemisphere; the right hemisphere elicited a steeper increase of the BOLD signal as a function of increasing effort. There was also a stronger functional connectivity within the central executive network because of increased task difficulty. Conclusion: The ability to allocate cognitive effort in complex working memory is contingent upon focused resources in the executive and in particular the salience network. Individual capacity during the complex working memory task is related to activity in the salience (but not the executive) network so that high-capacity participants evidence a lower signal and possibly hence a larger dynamic response. PMID:23616756

Prognostic factors for return-to-work following surgery for carpal tunnel syndrome: a systematic review.

PubMed

Peters, Susan; Johnston, Venerina; Hines, Sonia; Ross, Mark; Coppieters, Michel

2016-09-01

Carpal tunnel syndrome (CTS) is a common problem, that can be effectively managed by surgery. Screening for prognostic factors is important to identify workers who are at a greater risk of a poor work outcome in order to implement tailored interventions to facilitate their return-to-work. To synthesize the best available evidence on the association of preoperative prognostic factors with work-related outcomes in people who have undergone carpal tunnel surgery. Participants included those who were employed at the time of surgery, underwent carpal tunnel surgery and planned to return-to-work. The primary outcome was return-to-work. Quantitative studies investigating at least one prognostic factor for a work-related outcome in studies of workers who had carpal tunnel surgery were considered. Eleven electronic databases were searched from their respective inception date up to July 2015. A total of 3893 publications were reviewed. The quality of the included studies was assessed by two reviewers using a modified version of an appraisal tool (Joanna Briggs Institute Meta-analysis of Statistical Assessment and Review Instrument [JBI-MAStARI]). The following criteria were evaluated: study population representativeness, clearly defined prognostic factors and outcomes, potential confounding variables and appropriate statistical analysis. Data extraction was performed using a modified version of the standardized extraction tool from JBI-MAStARI. Statistical pooling was not possible. Findings are presented in tables and narrative format. Eleven studies (13 publications) investigating 93 prognostic factors for delayed return-to-work or prolonged work disability outcomes and 27 prognostic factors for work role functioning in 4187 participants were identified.Prognostic factors associated with workers' increased likelihood of an earlier return-to-work in a moderate-to-high-quality study included worker expected or desired fewer days off work, occupation, lower pain anxiety and if CTS had not altered their work role.Prognostic factors for a poorer work-related outcome included older age, lower household income, greater upper extremity functional limitation, greater than two musculoskeletal pain sites, lower recovery expectations, worse mental health status, job accommodation availability, high job strain, high job demands with high job control, poor co-worker relationships, poor baseline work role functioning, less-supportive workplace policies, preoperative work absence due to CTS or work disability of any cause, workers' compensation status, attorney involvement, and post-diagnosis surgical wait time. For workers who have had carpal tunnel surgery, there are a number of factors which may be modified in order to improve return-to-work times.

Effects of Contact-Induced Doping on the Behaviors of Organic Photovoltaic Devices

DOE PAGES

Wang, Jian; Xu, Liang; Lee, Yun -Ju; ...

2015-10-09

Substrates can significantly affect the electronic properties of organic semiconductors. In this paper, we report the effects of contact-induced doping, arising from charge transfer between a high work function hole extraction layer (HEL) and the organic active layer, on organic photovoltaic device performance. Employing a high work function HEL is found to increase doping in the active layer and decrease photocurrent. Combined experimental and modeling investigations reveal that higher doping increases polaron–exciton quenching and carrier recombination within the field-free region. Consequently, there exists an optimal HEL work function that enables a large built-in field while keeping the active layer dopingmore » low. This value is found to be ~0.4 eV larger than the pinning level of the active layer material. As a result, these understandings establish a criterion for optimal design of the HEL when adapting a new active layer system and can shed light on optimizing performance in other organic electronic devices.« less

Studies of thermionic materials for space power applications

NASA Technical Reports Server (NTRS)

1972-01-01

The effect of microstructures of tungsten cladding on the transport rates of carbide fuel components was studied at 2073 K. hyperstoichiometric 90UC-10ZrC containing 4 wt% tungsten was clad with six types of tungsten material of 40 mil thickness. Screening tests of 1000 hours were carried out, and then selected samples were subjected to long-term tests up to 10,000 hours. The results indicate that the microstructures strongly affect the transport rates of carbide fuel components. The conditions for preparing (110) oriented cylindrical chloride tungsten emitters of high vacuum work functions were also investigated. Specimen sets were deposited on fluoride tungsten substrates for evaluating the effects of various deposition parameters on the degree and uniformity of the (110) preferred orientation and the vacuum work function. Long-term tests showed that the high vacuum work function of a cylindrical emitter was stable and the chloride tungsten to fluoride tungsten bond remained in excellent shape after 4850 hours at 2073 K.

The Effect of Pressure on High- and Low-Working-Memory Students: An Elaboration of the Choking under Pressure Hypothesis

ERIC Educational Resources Information Center

Wang, Zuowei; Shah, Priti

2014-01-01

Sample: Fifty-three third and fourth graders from China participated in this study. Method: Participants' working memory (WM) was assessed by the Automated Operation Span task. Then, they solved mental addition problems of different types under low- and high-pressure conditions. Performance was analysed as a function of pressure condition, working…

The association between retirement and emotional well-being: does prior work-family conflict matter?

PubMed

Coursolle, Kathryn M; Sweeney, Megan M; Raymo, James M; Ho, Jeong-Hwa

2010-09-01

This study investigates whether the association between retirement and emotional well-being depends on prior experience of work-family conflict. We use data from the 1993 and 2004 waves of the Wisconsin Longitudinal Study to estimate linear regression models of 2 dimensions of emotional well-being-depressive symptoms and positive psychological functioning. We also use fixed effects models to investigate whether key findings persist after controlling for stable, but unobserved, characteristics of individuals. Retirement is associated with relatively fewer depressive symptoms among individuals who reported high levels of work stress interfering with family life in late midlife. We find suggestive evidence of a similar association with respect to positive psychological functioning after accounting for unobserved characteristics of individuals. Among individuals reporting high levels of family stress spillover into work life at late midlife, our results suggest that retirement tends to be associated with better emotional well-being among men than among women. Retirement may come more as a relief than as a stressor for individuals previously experiencing high levels of work demands interfering with family life. However, particularly among women, retirement may not relieve the burdens of family life stressors.

Fluid intelligence and executive functioning more alike than different?

PubMed

van Aken, Loes; Kessels, Roy P C; Wingbermühle, Ellen; van der Veld, William M; Egger, Jos I M

2016-02-01

Fluid intelligence (Gf) has been related to executive functioning (EF) in previous studies, and it is also known to be correlated with crystallized intelligence (Gc). The present study includes representative measures of Gf, Gc, and EF frequently used in clinical practice to examine this Gf-EF relation. It is hypothesised that the Gf-EF relation is higher than the Gc-EF relation, and that working memory in particular (as a measure of EF) shows a high contribution to this relation. Confirmatory factor analysis was performed on a mixed neuropsychiatric and non-clinical sample consisting of 188 participants, using the Kaufman Adolescent and Adult Intelligence Test, and three executive tasks of the Cambridge Neuropsychological Test Automated Battery, covering working memory, planning skills, and set shifting. The model fitted the data well [χ²(24)=35.25, p=0.07, RMSEA=0.050]. A very high correlation between Gf and EF was found (0.91), with working memory being the most profound indicator. A moderate to high correlation between Gc and EF was present. Current results are consistent with findings of a strong relation between Gf and working memory. Gf and EF are highly correlated. Gf dysfunction in neuropsychiatric patients warrants further EF examination and vice versa. It is discussed that results confirm the need to distinguish between specific versus general fluid/executive functioning, the latter being more involved when task complexity and novelty increase. This distinction can provide a more refined differential diagnosis and improve neuropsychiatric treatment indication.

Auditory evoked functions in ground crew working in high noise environment of Mumbai airport.

PubMed

Thakur, L; Anand, J P; Banerjee, P K

2004-10-01

The continuous exposure to the relatively high level of noise in the surroundings of an airport is likely to affect the central pathway of the auditory system as well as the cognitive functions of the people working in that environment. The Brainstem Auditory Evoked Responses (BAER), Mid Latency Response (MLR) and P300 response of the ground crew employees working in Mumbai airport were studied to evaluate the effects of continuous exposure to high level of noise of the surroundings of the airport on these responses. BAER, P300 and MLR were recorded by using a Nicolet Compact-4 (USA) instrument. Audiometry was also monitored with the help of GSI-16 Audiometer. There was a significant increase in the peak III latency of the BAER in the subjects exposed to noise compared to controls with no change in their P300 values. The exposed group showed hearing loss at different frequencies. The exposure to the high level of noise caused a considerable decline in the auditory conduction upto the level of the brainstem with no significant change in conduction in the midbrain, subcortical areas, auditory cortex and associated areas. There was also no significant change in cognitive function as measured by P300 response.

The effects of working memory training on functional brain network efficiency.

PubMed

Langer, Nicolas; von Bastian, Claudia C; Wirz, Helen; Oberauer, Klaus; Jäncke, Lutz

2013-10-01

The human brain is a highly interconnected network. Recent studies have shown that the functional and anatomical features of this network are organized in an efficient small-world manner that confers high efficiency of information processing at relatively low connection cost. However, it has been unclear how the architecture of functional brain networks is related to performance in working memory (WM) tasks and if these networks can be modified by WM training. Therefore, we conducted a double-blind training study enrolling 66 young adults. Half of the subjects practiced three WM tasks and were compared to an active control group practicing three tasks with low WM demand. High-density resting-state electroencephalography (EEG) was recorded before and after training to analyze graph-theoretical functional network characteristics at an intracortical level. WM performance was uniquely correlated with power in the theta frequency, and theta power was increased by WM training. Moreover, the better a person's WM performance, the more their network exhibited small-world topology. WM training shifted network characteristics in the direction of high performers, showing increased small-worldness within a distributed fronto-parietal network. Taken together, this is the first longitudinal study that provides evidence for the plasticity of the functional brain network underlying WM. Copyright © 2013 Elsevier Ltd. All rights reserved.

Organizational nostalgia lowers turnover intentions by increasing work meaning: The moderating role of burnout.

PubMed

Leunissen, Joost M; Sedikides, Constantine; Wildschut, Tim; Cohen, Taya R

2018-01-01

We report 3 studies addressing the relevance of organizational nostalgia for the meaning that employees ascribe to their work (work meaning). We hypothesized, and found, that organizational nostalgia enhances work meaning and thereby reduces turnover intentions. In Study 1, an employee survey, spontaneously experienced organizational nostalgia was associated with higher work meaning. In Study 2, an organizational-nostalgia induction increased work meaning, which subsequently predicted lowered turnover intentions. In Study 3, an organizational-nostalgia induction increased work meaning and thereby lowered turnover intentions, especially among employees who reported relatively high levels of burnout. When burnout is high, organizational nostalgia functions as a rich source of meaning that benefits employees' work experience. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Executive Function and Temperamental Fear Concurrently Predict Deception in School-Aged Children.

PubMed

Babkirk, Sarah; Saunders, Lauren V; Solomon, Beylul; Kessel, Ellen M; Crossman, Angela; Gokhan, Nurper; Dennis, Tracy A

The decision to intentionally withhold truthful information, or deception, is a key component of moral development and may be a precursor to more serious anti-social tendencies. Two factors, executive function and temperamental fear are each thought to influence childhood deception. Few studies, however, have explored deception in relation to both of these factors simultaneously. This was the goal of the present study. Executive function, as measured by a working memory task, and temperamental fear, as measured via maternal report were assessed in relation to observed deceptive behavior among 6 - 9-year-old children ( N = 43). Results showed that children displaying high working memory capacity and high temperamental fear were more likely to exhibit deceptive behavior. Implications for predictors of childhood deception and applications for moral education are discussed.

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.

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

[Current status of operations in community general support centers and the correlation of personal traits, work environment and occupational stress].

PubMed

Yamaguchi, Yoshie

2010-01-01

The purpose of this study was to identify the current status of operations at community general support centers which provide coordination for elderly care and the correlation of personal traits, work environment and the occupational stress of the staff. Subjects of the study were 251 staff members of community general support centers. The current status of operations at the community general support centers and the personal traits, work environment, effort-remuneration imbalance model (ERI) and general health questionnaire (GHQ) were surveyed. The initial analysis involved a comparison by a chi-square test on: The effort-remuneration ratio (E/R ratio) of personal traits and work environment, risk of over-commitment (OC), and GHQ score. To explore the correlation between the E/R ratio of the three GHQ groups (low, middle and high score groups) and the OC value, one-way analysis of variance was performed. Out of the four basic functions of the community general support centers, 22.0% of the respondents noted that "establishment of a regional, comprehensive/multi-tiered service network" was functioning, and 50.4% of respondents noted that "comprehensive and continuous care management" was functioning. The average effort score was 15.5 +/- 5.3, approximately double the average value of preceding studies. Significant differences found in GHQ scores were related to working hours (p<0.001) and anxiety was related to task content (p<0.001). Moreover, a higher GHQ score was accompanied by a higher E/R ratio and as a result of the multiple comparison, a marked difference was observed between the GHQ low score group and the GHQ high score group (p<0.001), and a significant difference was also found between the GHQ low score group and GHQ medium score group (p=0.012). Items observed to have significant correlation with high E/R ratio were: "Weekly working hours of 50 h or more" (OR: 10.38, 95% CI: 2.52-42.70), "Unstable employment" (OR: 2.75, 95% CI: 1.22-6.21) and "Anxiety related to task content" (OR: 17.04, 95% CI: 3.57-81.24). Items observed to have significant correlation with OC value risk factors were: "Weekly working hours of 50 h or more" (OR: 8.04, 95% CI: 1.99-32.41) and "Anxiety related to task content" (OR: 4.60, 95% CI: 2.04-10.37). We conclude that the basic functions of the community general support centers are not presently very functional. The stress levels of the community general support center staff are high and their health levels are low. This indicates that staff are forced to work with anxiety related to task content under conditions of poor pay and long working hours.

Task Engagement in Young Adults with High-Functioning Autism Spectrum Disorders: Generalization Effects of Behavioral Skills Training

ERIC Educational Resources Information Center

Palmen, Annemiek; Didden, Robert

2012-01-01

This study evaluated the effectiveness of a behavioral skills training package on task engagement in six young adults with high-functioning ASD who worked in a regular job-training setting. Experimental sessions were implemented in a small-group training format in a therapy room using unknown tasks. Data were collected on participant's off-task…

Dryden historian Christian Gelzer explains functions of a high-altitude pressure suit to (left to right) Brandon Blankenship, Garrett Clay and Eddie Patterson

NASA Image and Video Library

2004-06-22

NASA Dryden historian Christian Gelzer explains functions of the high-altitude pressure suit he is wearing to (left to right) Brandon Blankenship and Garrett Clay of Lancaster and Eddie Patterson of Tehachapi during Take Your Children to Work Day activities at NASA Dryden Flight Research Center June 22.

Incorporating Functional Imaging Information into rpFNA Analysis for Breast Cancer Detection in High Risk Women

DTIC Science & Technology

2010-03-01

TITLE: INCORPORATING FUNCTIONAL IMAGING INFORMATION TO rpFNA ANALYSIS FOR BREAST CANCER DETECTION IN HIGH-RISK WOMEN PRINCIPAL INVESTIGATOR...Imaging Information into rpFNA 5a. CONTRACT NUMBER Analysis for Breast Cancer Detection in High Risk Women 5b. GRANT NUMBER W81XWH-08-1-0192 5c...results of random periareolar fine needle aspiration (rpFNA) in women at high risk for breast cancer. In this second year of work, efforts have been

Negative ion source with hollow cathode discharge plasma

DOEpatents

Hershcovitch, Ady; Prelec, Krsto

1983-01-01

A negative ion source of the type where negative ions are formed by bombarding a low-work-function surface with positive ions and neutral particles from a plasma, wherein a highly ionized plasma is injected into an anode space containing the low-work-function surface. The plasma is formed by hollow cathode discharge and injected into the anode space along the magnetic field lines. Preferably, the negative ion source is of the magnetron type.

Protection of brain and pancreas from high-fat diet: effects of catechin and caffeine.

PubMed

Unno, Keiko; Yamamoto, Hiroyuki; Maeda, Ken-Ichi; Takabayashi, Fumiyo; Yoshida, Hirotoshi; Kikunaga, Naomi; Takamori, Nina; Asahina, Shunsuke; Iguchi, Kazuaki; Sayama, Kazutoshi; Hoshino, Minoru

2009-02-16

To investigate the effect of a high-fat diet on brain and pancreas functions, we used SAMP10 mice that have characteristics of brain atrophy and cognitive dysfunction with aging. Simultaneously, we investigated the effect of green tea catechin consumption on high-fat diet feeding, because green tea catechin has been reported to improve brain atrophy, brain dysfunction and obesity. The body weight of mice fed a high-fat diet from 2 to 12 months was higher than that of the control, although the calorie intake was not. The high-fat diet also increased insulin secretion; however, the hypersecretion of insulin and obesity were suppressed when mice were fed a high-fat diet with green tea catechin and caffeine. Furthermore, brain atrophy was suppressed and the working memory, tested using Y-maze, improved in mice fed a high-fat diet containing green tea catechin and caffeine. The secretion of insulin might affect both obesity and brain function. A strong correlation was found between working memory and insulin release in mice fed a high-fat diet with green tea catechin and/or caffeine. The results indicate the protective effect of green tea catechin and caffeine on the functions of brain and pancreas in mice fed a high-fat diet.

Impact of IQ Discrepancy on Executive Function in High-Functioning Autism: Insight into Twice Exceptionality

ERIC Educational Resources Information Center

Kalbfleisch, M. Layne; Loughan, Ashlee R.

2012-01-01

We examined the impact of IQ discrepancy (IQD) within (1) and above (1+) one standard deviation on executive function in HFA using the BRIEF. We hypothesized that IQD would benefit executive function. IQD 1 is hallmarked by deficits in BRIEF indices and subscales inhibit, shift, initiate, working memory, planning and organization, and monitor…

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.

Relationship between cognitive functions and prevalence of fatigue in elementary and junior high school students.

PubMed

Mizuno, Kei; Tanaka, Masaaki; Fukuda, Sanae; Imai-Matsumura, Kyoko; Watanabe, Yasuyoshi

2011-06-01

Fatigue is a common complaint among elementary and junior high school students, and is related to poor academic performance. Since grade-dependent development of cognitive functions also influences academic performance, we attempted to determine whether cognitive functions were associated with the prevalence of fatigue. Participants were 148 elementary school students from 4th- to 6th-grades and 152 junior high school students from 7th- to 9th-grades. Participants completed a questionnaire about fatigue (Japanese version of the Chalder Fatigue Scale) and paper-and-pencil and computerized cognitive tests which could evaluate the abilities of motor processing, immediate, delayed and working memory, selective, divided and alternative attention, retrieve learned material, and spatial construction. We found that in multivariate logistic regression analyses adjusted for grade and gender, slow motor processing was positively correlated with the prevalence of fatigue in the elementary school students and decreases in working memory and divided and alternative attention processing were positively correlated with the prevalence of fatigue in the junior high school students. The grade-dependent development of cognitive function influences the severity of fatigue in elementary and junior high school students. Copyright © 2010 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved.

Heat stress, dehydration, and kidney function in sugarcane cutters in El Salvador--A cross-shift study of workers at risk of Mesoamerican nephropathy.

PubMed

García-Trabanino, Ramón; Jarquín, Emmanuel; Wesseling, Catharina; Johnson, Richard J; González-Quiroz, Marvin; Weiss, Ilana; Glaser, Jason; José Vindell, Juan; Stockfelt, Leo; Roncal, Carlos; Harra, Tamara; Barregard, Lars

2015-10-01

An epidemic of progressive kidney failure afflicts sugarcane workers in Central America. Repeated high-intensity work in hot environments is a possible cause. To assess heat stress, dehydration, biomarkers of renal function and their possible associations. A secondary aim was to evaluate the prevalence of pre-shift renal damage and possible causal factors. Sugarcane cutters (N=189, aged 18-49 years, 168 of them male) from three regions in El Salvador were examined before and after shift. Cross-shift changes in markers of dehydration and renal function were examined and associations with temperature, work time, region, and fluid intake were assessed. Pre-shift glomerular filtration rate was estimated (eGFR) from serum creatinine. The mean work-time was 4 (1.4-11) hours. Mean workday temperature was 34-36 °C before noon, and 39-42 °C at noon. The mean liquid intake during work was 0.8L per hour. There were statistically significant changes across shift. The mean urine specific gravity, urine osmolality and creatinine increased, and urinary pH decreased. Serum creatinine, uric acid and urea nitrogen increased, while chloride and potassium decreased. Pre-shift serum uric acid levels were remarkably high and pre-shift eGFR was reduced (<60 mL/min) in 23 male workers (14%). The high prevalence of reduced eGFR, and the cross-shift changes are consistent with recurrent dehydration from strenuous work in a hot and humid environment as an important causal factor. The pathophysiology may include decreased renal blood flow, high demands on tubular reabsorption, and increased levels of uric acid. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

A longitudinal study of neuropsychological functioning and academic achievement in children with and without signs of attention-deficit/hyperactivity disorder.

PubMed

Rennie, Brandon; Beebe-Frankenberger, Margaret; Swanson, H Lee

2014-01-01

Attention-deficit/hyperactivity disorder (ADHD) in childhood is associated with poor academic functioning. Deficits in academic functioning have proven to be less responsive to intervention than behavioral deficits in this population, yet the causes of this academic underperformance are not well understood. The purpose of this study is to examine the relationship between ADHD and academic performance in elementary-aged children in a developmental context. To do this, we study important cognitive variables and academic achievement over a three-year timeframe. Based on teacher ratings of ADHD, children were divided into a high symptom group (n = 17) and a low symptom group (n = 34). A thorough battery of cognitive and academic tests was administered at Time 1 and again 2 years later. Cognitive measures focused specifically on working memory and response inhibition. RESULTS indicate that children who have high levels of ADHD signs differ from their low-sign peers in academic achievement and in several cognitive domains. Differences in cognitive functioning show a developmental trend consistent with earlier developmental delays in response inhibition and later delays in working memory. Working memory appears to be particularly important in several academic domains. Importantly, in a longitudinal model, working memory was more predictive of math achievement for students demonstrating signs of ADHD than for those who did not. The relationship between these cognitive variables and academic functioning are explicated in the domains of reading, math, and problem solving.

Training on Movement Figure-Ground Discrimination Remediates Low-Level Visual Timing Deficits in the Dorsal Stream, Improving High-Level Cognitive Functioning, Including Attention, Reading Fluency, and Working Memory.

PubMed

Lawton, Teri; Shelley-Tremblay, John

2017-01-01

The purpose of this study was to determine whether neurotraining to discriminate a moving test pattern relative to a stationary background, figure-ground discrimination, improves vision and cognitive functioning in dyslexics, as well as typically-developing normal students. We predict that improving the speed and sensitivity of figure-ground movement discrimination ( PATH to Reading neurotraining) acts to remediate visual timing deficits in the dorsal stream, thereby improving processing speed, reading fluency, and the executive control functions of attention and working memory in both dyslexic and normal students who had PATH neurotraining more than in those students who had no neurotraining. This prediction was evaluated by measuring whether dyslexic and normal students improved on standardized tests of cognitive skills following neurotraining exercises, more than following computer-based guided reading ( Raz-Kids ( RK )). The neurotraining used in this study was visually-based training designed to improve magnocellular function at both low and high levels in the dorsal stream: the input to the executive control networks coding working memory and attention. This approach represents a paradigm shift from the phonologically-based treatment for dyslexia, which concentrates on high-level speech and reading areas. This randomized controlled-validation study was conducted by training the entire second and third grade classrooms (42 students) for 30 min twice a week before guided reading. Standardized tests were administered at the beginning and end of 12-weeks of intervention training to evaluate improvements in academic skills. Only movement-discrimination training remediated both low-level visual timing deficits and high-level cognitive functioning, including selective and sustained attention, reading fluency and working memory for both dyslexic and normal students. Remediating visual timing deficits in the dorsal stream revealed the causal role of visual movement discrimination training in improving high-level cognitive functions such as attention, reading acquisition and working memory. This study supports the hypothesis that faulty timing in synchronizing the activity of magnocellular with parvocellular visual pathways in the dorsal stream is a fundamental cause of dyslexia and being at-risk for reading problems in normal students, and argues against the assumption that reading deficiencies in dyslexia are caused by phonological or language deficits, requiring a paradigm shift from phonologically-based treatment of dyslexia to a visually-based treatment. This study shows that visual movement-discrimination can be used not only to diagnose dyslexia early, but also for its successful treatment, so that reading problems do not prevent children from readily learning.

Training on Movement Figure-Ground Discrimination Remediates Low-Level Visual Timing Deficits in the Dorsal Stream, Improving High-Level Cognitive Functioning, Including Attention, Reading Fluency, and Working Memory

PubMed Central

Lawton, Teri; Shelley-Tremblay, John

2017-01-01

The purpose of this study was to determine whether neurotraining to discriminate a moving test pattern relative to a stationary background, figure-ground discrimination, improves vision and cognitive functioning in dyslexics, as well as typically-developing normal students. We predict that improving the speed and sensitivity of figure-ground movement discrimination (PATH to Reading neurotraining) acts to remediate visual timing deficits in the dorsal stream, thereby improving processing speed, reading fluency, and the executive control functions of attention and working memory in both dyslexic and normal students who had PATH neurotraining more than in those students who had no neurotraining. This prediction was evaluated by measuring whether dyslexic and normal students improved on standardized tests of cognitive skills following neurotraining exercises, more than following computer-based guided reading (Raz-Kids (RK)). The neurotraining used in this study was visually-based training designed to improve magnocellular function at both low and high levels in the dorsal stream: the input to the executive control networks coding working memory and attention. This approach represents a paradigm shift from the phonologically-based treatment for dyslexia, which concentrates on high-level speech and reading areas. This randomized controlled-validation study was conducted by training the entire second and third grade classrooms (42 students) for 30 min twice a week before guided reading. Standardized tests were administered at the beginning and end of 12-weeks of intervention training to evaluate improvements in academic skills. Only movement-discrimination training remediated both low-level visual timing deficits and high-level cognitive functioning, including selective and sustained attention, reading fluency and working memory for both dyslexic and normal students. Remediating visual timing deficits in the dorsal stream revealed the causal role of visual movement discrimination training in improving high-level cognitive functions such as attention, reading acquisition and working memory. This study supports the hypothesis that faulty timing in synchronizing the activity of magnocellular with parvocellular visual pathways in the dorsal stream is a fundamental cause of dyslexia and being at-risk for reading problems in normal students, and argues against the assumption that reading deficiencies in dyslexia are caused by phonological or language deficits, requiring a paradigm shift from phonologically-based treatment of dyslexia to a visually-based treatment. This study shows that visual movement-discrimination can be used not only to diagnose dyslexia early, but also for its successful treatment, so that reading problems do not prevent children from readily learning. PMID:28555097

Executive and Visuo-Motor Function in Adolescents and Adults with Autism Spectrum Disorder

ERIC Educational Resources Information Center

Sachse, Michael; Schlitt, Sabine; Hainz, Daniela; Ciaramidaro, Angela; Schirman, Shella; Walter, Henrik; Poustka, Fritz; Bolte, Sven; Freitag, Christine M.

2013-01-01

This study broadly examines executive (EF) and visuo-motor function in 30 adolescent and adult individuals with high-functioning autism spectrum disorder (ASD) in comparison to 28 controls matched for age, gender, and IQ. ASD individuals showed impaired spatial working memory, whereas planning, cognitive flexibility, and inhibition were spared.…

Students' Recognition of Function Transformations' Themes Associated with the Algebraic Representation

ERIC Educational Resources Information Center

Daher, Wajeeh M.; Anabousi, Anlam A.

2015-01-01

The topic of function transformations is a difficult mathematical topic for school and college students. This article examines how students conceive function transformations after working with GeoGebra, when this conceiving relates to the algebraic representation. The research participants were 19 ninth grade high achieving students who learned,…

Spectral observations of hole injection with transition metal oxides for an efficient organic light-emitting diode

NASA Astrophysics Data System (ADS)

Chiu, Tien-Lung; Chuang, Ya-Ting

2015-02-01

Transition metal oxides, such as molybdenum trioxide (MoO3), tungsten trioxide (WO3) and vanadium pent-oxide (V2O5), are well-known hole injection materials used for organic electronic devices. These materials promote work functions of anodes, reduce energy barriers, and facilitate hole transport at the interface between the inorganic anode and organic hole-transporting layer (HTL). In this study, we characterized the transmittance spectra and work function of these materials. Furthermore, we employed a hole-injection layer (HIL) in a blue phosphorescent organic light-emitting diode (OLED) to evaluate their hole-injection capacity by detecting the variation in the emission spectra. Thus, we utilized an OLED structure that has fast electron transporting dynamics to establish the recombination zone located at emitting layer and a partial HTL close to the anode. We used these three transition metal oxides individually as HILs sandwiched between the ITO anode and HTL and concluded that the strength of emissive light from the HTL was determined by their hole-injection capacity, depending on work function. The small amount of HTL emission light of the V2O5 OLED was explained by the high work function of 5.8 eV for the V2O5 film. However, the V2O5 OLED demonstrated the least favorable optoelectrical performance because of its low transmittance and high resistance of the V2O5 film. Ultimately, the 5 nm-MoO3 OLED exhibited the highest device performance because of its high material conductivity and transparency in the visible band.

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.

[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

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

Text mining and network analysis to find functional associations of genes in high altitude diseases.

PubMed

Bhasuran, Balu; Subramanian, Devika; Natarajan, Jeyakumar

2018-05-02

Travel to elevations above 2500 m is associated with the risk of developing one or more forms of acute altitude illness such as acute mountain sickness (AMS), high altitude cerebral edema (HACE) or high altitude pulmonary edema (HAPE). Our work aims to identify the functional association of genes involved in high altitude diseases. In this work we identified the gene networks responsible for high altitude diseases by using the principle of gene co-occurrence statistics from literature and network analysis. First, we mined the literature data from PubMed on high-altitude diseases, and extracted the co-occurring gene pairs. Next, based on their co-occurrence frequency, gene pairs were ranked. Finally, a gene association network was created using statistical measures to explore potential relationships. Network analysis results revealed that EPO, ACE, IL6 and TNF are the top five genes that were found to co-occur with 20 or more genes, while the association between EPAS1 and EGLN1 genes is strongly substantiated. The network constructed from this study proposes a large number of genes that work in-toto in high altitude conditions. Overall, the result provides a good reference for further study of the genetic relationships in high altitude diseases. Copyright © 2018 Elsevier Ltd. All rights reserved.

Does adolescent risk taking imply weak executive function? A prospective study of relations between working memory performance, impulsivity, and risk taking in early adolescence.

PubMed

Romer, Daniel; Betancourt, Laura M; Brodsky, Nancy L; Giannetta, Joan M; Yang, Wei; Hurt, Hallam

2011-09-01

Studies of brain development suggest that the increase in risk taking observed during adolescence may be due to insufficient prefrontal executive function compared to a more rapidly developing subcortical motivation system. We examined executive function as assessed by working memory ability in a community sample of youth (n = 387, ages 10 to 12 at baseline) in three annual assessments to determine its relation to two forms of impulsivity (sensation seeking and acting without thinking) and a wide range of risk and externalizing behavior. Using structural equation modeling, we tested a model in which differential activation of the dorsal and ventral striatum produces imbalance in the function of these brain regions. For youth high in sensation seeking, both regions were predicted to develop with age. However, for youth high in the tendency to act without thinking, the ventral striatum was expected to dominate. The model predicted that working memory ability would exhibit (1) early weakness in youth high in acting without thinking but (2) growing strength in those high in sensation seeking. In addition, it predicted that (3) acting without thinking would be more strongly related to risk and externalizing behavior than sensation seeking. Finally, it predicted that (4) controlling for acting without thinking, sensation seeking would predict later increases in risky and externalizing behavior. All four of these predictions were confirmed. The results indicate that the rise in sensation seeking that occurs during adolescence is not accompanied by a deficit in executive function and therefore requires different intervention strategies from those for youth whose impulsivity is characterized by early signs of acting without thinking. © 2011 Blackwell Publishing Ltd.

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.

Working memory and attentional bias on reinforcing efficacy of food.

PubMed

Carr, Katelyn A; Epstein, Leonard H

2017-09-01

Reinforcing efficacy of food, or the relationship between food prices and purchasing, is related to obesity status and energy intake in adults. Determining how to allocate resources for food is a decision making process influenced by executive functions. Attention to appetitive cues, as well as working memory capacity, or the ability to flexibly control attention while mentally retaining information, may be important executive functions involved in food purchasing decisions. In two studies, we examined how attention bias to food and working memory capacity are related to reinforcing efficacy of both high energy-dense and low energy-dense foods. The first study examined 48 women of varying body mass index (BMI) and found that the relationship between attentional processes and reinforcing efficacy was moderated by working memory capacity. Those who avoid food cues and had high working memory capacity had the lowest reinforcing efficacy, as compared to those with low working memory capacity. Study 2 systematically replicated the methods of study 1 with assessment of maintained attention in a sample of 48 overweight/obese adults. Results showed the relationship between maintained attention to food cues and reinforcing efficacy was moderated by working memory capacity. Those with a maintained attention to food and high working memory capacity had higher reinforcing efficacy than low working memory capacity individuals. These studies suggest working memory capacity moderated the relationship between different aspects of attention and food reinforcement. Understanding how decision making process are involved in reinforcing efficacy may help to identify future intervention targets. Copyright © 2017 Elsevier Ltd. All rights reserved.

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

Burke, J.V.

The published work on exact penalization is indeed vast. Recently this work has indicated an intimate relationship between exact penalization, Lagrange multipliers, and problem stability or calmness. In the present work we chronicle this development within a simple idealized problem framework, wherein we unify, extend, and refine much of the known theory. In particular, most of the foundations for constrained optimization are developed with the aid of exact penalization techniques. Our approach is highly geometric and is based upon the elementary subdifferential theory for distance functions. It is assumed that the reader is familiar with the theory of convex setsmore » and functions. 54 refs.« less

Skill Flexibility among Schoolteachers: Operationalization and Organizational Implications.

ERIC Educational Resources Information Center

Rosenblatt, Zehava; Inbal, Batia

1999-01-01

Investigates effects of skill flexibility on Israeli secondary teachers' work attitudes and job performance. Both role and functional flexibility were associated with improved teachers' work performance; role flexibility is linked to high organizational commitment and low powerlessness. Principals appreciate skill flexibility, but organizational…

Kitchen Units for the Classroom.

ERIC Educational Resources Information Center

Illinois Univ., Urbana. Agricultural Experiment Station.

This study is concerned with functional standards for storage of equipment, use of space, and arrangement of work centers in kitchen units for four students within a high school foods laboratory. Lists of equipment and measurements for storage areas are given for each work center. (FS)

Work instability and financial loss in early inflammatory arthritis.

PubMed

Looper, Karl J; Mustafa, Sally S; Zelkowitz, Phyllis; Purden, Margaret; Baron, Murray

2012-12-01

Inflammatory arthritis is associated with a high degree of work instability and financial burden. In this study, we examine the extent of work instability and financial loss as well as their association with disease characteristics during the first 18 months of inflammatory arthritis. One hundred and four patients in the early phase (more than 6 weeks, < 18 months) of inflammatory arthritis were recruited from a larger early inflammatory arthritis registry. Questionnaires recorded sociodemographic data and disease characteristics, including pain assessed using the Short Form McGill Pain Questionnaire (MPQ) and physical functioning measured with the Medical Outcomes Study Short Form 36 (SF-36) physical functioning score. The Rheumatoid Arthritis Work Instability Scale (RA-WIS) was used to measure patient-perceived functioning in the workplace and the Financial Loss Questionnaire (FLQ) measured the impact on family finances. Participants' mean age was 56 years, 70.2% were female and 49.0% were working. Average yearly household income was < 60 000 Canadian dollars (CAD) for 38.5% of the sample. Of our working patients, 43% had a medium or high risk of work loss as measured by the RA-WIS and 35% reported a financial loss. On multivariate analysis, MPQ and SF-36 contributed to the dependent variable work instability, while age and SF-36 contributed to financial loss. This study identifies pain and physical dysfunction as potential modifiable risk factors for negative socioeconomic repercussions of illness in early inflammatory arthritis. © 2012 The Authors International Journal of Rheumatic Diseases © 2012 Asia Pacific League of Associations for Rheumatology and Wiley Publishing Asia Pty Ltd.

Design of nanostructured-based glucose biosensors

NASA Astrophysics Data System (ADS)

Komirisetty, Archana; Williams, Frances; Pradhan, Aswini; Konda, Rajini B.; Dondapati, Hareesh; Samantaray, Diptirani

2012-04-01

This paper presents the design of glucose sensors that will be integrated with advanced nano-materials, bio-coatings and electronics to create novel devices that are highly sensitive, inexpensive, accurate, and reliable. In the work presented, a glucose biosensor and its fabrication process flow have been designed. The device is based on electrochemical sensing using a working electrode with bio-functionalized zinc oxide (ZnO) nano-rods. Among all metal oxide nanostructures, ZnO nano-materials play a significant role as a sensing element in biosensors due to their properties such as high isoelectric point (IEP), fast electron transfer, non-toxicity, biocompatibility, and chemical stability which are very crucial parameters to achieve high sensitivity. Amperometric enzyme electrodes based on glucose oxidase (GOx) are used due to their stability and high selectivity to glucose. The device also consists of silicon dioxide and titanium layers as well as platinum working and counter electrodes and a silver/silver chloride reference electrode. Currently, the biosensors are being fabricated using the process flow developed. Once completed, the sensors will be bio-functionalized and tested to characterize their performance, including their sensitivity and stability.

Negative ion source with hollow cathode discharge plasma

DOEpatents

Hershcovitch, A.; Prelec, K.

1980-12-12

A negative ion source of the type where negative ions are formed by bombarding a low-work-function surface with positive ions and neutral particles from a plasma, wherein a highly ionized plasma is injected into an anode space containing the low-work-function surface is described. The plasma is formed by hollow cathode discharge and injected into the anode space along the magnetic field lines. Preferably, the negative ion source is of the magnetron type.

Evolution of Metastable Defects and Its Effect on the Electronic Properties of MoS2 Films.

PubMed

Precner, M; Polaković, T; Qiao, Qiao; Trainer, D J; Putilov, A V; Di Giorgio, C; Cone, I; Zhu, Y; Xi, X X; Iavarone, M; Karapetrov, G

2018-04-30

We report on structural and electronic properties of defects in chemical vapor-deposited monolayer and few-layer MoS 2 films. Scanning tunneling microscopy, Kelvin probe force microscopy, and transmission electron microscopy were used to obtain high resolution images and quantitative measurements of the local density of states, work function and nature of defects in MoS 2 films. We track the evolution of defects that are formed under heating and electron beam irradiation. We observe formation of metastable domains with different work function values after annealing the material in ultra-high vacuum to moderate temperatures. We attribute these metastable values of the work function to evolution of crystal defects forming during the annealing. The experiments show that sulfur vacancies formed after exposure to elevated temperatures diffuse, coalesce, and migrate bringing the system from a metastable to equilibrium ground state. The process could be thermally or e-beam activated with estimated energy barrier for sulfur vacancy migration of 0.6 eV in single unit cell MoS 2 . Even at equilibrium conditions, the work function and local density of states values are strongly affected near grain boundaries and edges. The results provide initial estimates of the thermal budgets available for reliable fabrication of MoS 2 -based integrated electronics and indicate the importance of defect control and layer passivation.

Using Solution Strategies to Examine and Promote High-School Students' Understanding of Exponential Functions: One Teacher's Attempt

ERIC Educational Resources Information Center

Brendefur, Jonathan

2014-01-01

Much research has been conducted on how elementary students develop mathematical understanding and subsequently how teachers might use this information. This article builds on this type of work by investigating how one high-school algebra teacher designs and conducts a lesson on exponential functions. Through a lesson study format she studies with…

Bio-Inspired Human-Level Machine Learning

DTIC Science & Technology

2015-10-25

extensions to high-level cognitive functions such as anagram solving problem. 15. SUBJECT TERMS 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF...extensions to high-level cognitive functions such as anagram solving problem. We expect that the bio-inspired human-level machine learning combined with...numbers of 1011 neurons and 1014 synaptic connections in the human brain. In previous work, we experimentally demonstrated the feasibility of cognitive

Executive Function and Temperamental Fear Concurrently Predict Deception in School-Aged Children

PubMed Central

Babkirk, Sarah; Saunders, Lauren V.; Solomon, Beylul; Kessel, Ellen M.; Crossman, Angela; Gokhan, Nurper; Dennis, Tracy A.

2015-01-01

The decision to intentionally withhold truthful information, or deception, is a key component of moral development and may be a precursor to more serious anti-social tendencies. Two factors, executive function and temperamental fear are each thought to influence childhood deception. Few studies, however, have explored deception in relation to both of these factors simultaneously. This was the goal of the present study. Executive function, as measured by a working memory task, and temperamental fear, as measured via maternal report were assessed in relation to observed deceptive behavior among 6 – 9-year-old children (N = 43). Results showed that children displaying high working memory capacity and high temperamental fear were more likely to exhibit deceptive behavior. Implications for predictors of childhood deception and applications for moral education are discussed. PMID:26880858

A locus coeruleus-norepinephrine account of individual differences in working memory capacity and attention control.

PubMed

Unsworth, Nash; Robison, Matthew K

2017-08-01

Studies examining individual differences in working memory capacity (WMC) have suggested that low WMC individuals have particular deficits in attention control processes compared to high WMC individuals. In the current article we suggest that part of the WMC-attention control relation is due to variation in the functioning of the locus coeruleus-norepinephrine system (LC-NE). Specifically, we suggest that because of dysregulation of LC-NE functioning, the fronto-parietal control network for low WMC individuals is only weakly activated, resulting in greater default-mode network activity (and greater mind-wandering) for low WMC individuals compared to high WMC individuals. This results in disrupted attention control and overall more erratic performance (more lapses of attention) for low WMC individuals than for high WMC individuals. This framework is used to examine previous studies of individual differences in WMC and attention control, and new evidence is examined on the basis of predictions of the framework to pupillary responses as an indirect marker of LC-NE functioning.

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.

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

PubMed

Bakker, Arnold B; Oerlemans, Wido G M

2016-08-17

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

Work culture among healthcare personnel in a palliative medicine unit.

PubMed

André, Beate; Sjøvold, Endre; Rannestad, Toril; Holmemo, Marte; Ringdal, Gerd I

2013-04-01

Understanding and assessing health care personnel's work culture in palliative care is important, as a conflict between "high tech" and "high touch" is present. Implementing necessary changes in behavior and procedures may imply a profound challenge, because of this conflict. The aim of this study was to explore the work culture at a palliative medicine unit (PMU). Healthcare personnel (N = 26) at a PMU in Norway comprising physicians, nurses, physiotherapists, and others filled in a questionnaire about their perception of the work culture at the unit. The Systematizing Person-Group Relations (SPGR) method was used for gathering data and for the analyses. This method applies six different dimensions representing different aspects of a work culture (Synergy, Withdrawal, Opposition, Dependence, Control, and Nurture) and each dimension has two vectors applied. The method seeks to explore which aspects dominate the particular work culture, identifying challenges, limitations, and opportunities. The findings were compared with a reference group of 347 ratings of well-functioning Norwegian organizations, named the "Norwegian Norm." The healthcare personnel working at the PMU had significantly higher scores than the "Norwegian Norm" in both vectors in the "Withdrawal" dimension and significant lower scores in both vectors in the "Synergy," "Control," and "Dependence" dimensions. Healthcare personnel at the PMU have a significantly different perception of their work culture than do staff in "well-functioning organizations" in several dimensions. The low score in the "Synergy" and "Control" dimensions indicate lack of engagement and constructive goal orientation behavior, and not being in a position to change their behavior. The conflict between "high tech" and "high touch" at a PMU seems to be an obstacle when implementing new procedures and alternative courses of action.

Graphene oxide/graphene vertical heterostructure electrodes for highly efficient and flexible organic light emitting diodes

NASA Astrophysics Data System (ADS)

Jia, S.; Sun, H. D.; Du, J. H.; Zhang, Z. K.; Zhang, D. D.; Ma, L. P.; Chen, J. S.; Ma, D. G.; Cheng, H. M.; Ren, W. C.

2016-05-01

The relatively high sheet resistance, low work function and poor compatibility with hole injection layers (HILs) seriously limit the applications of graphene as transparent conductive electrodes (TCEs) for organic light emitting diodes (OLEDs). Here, a graphene oxide/graphene (GO/G) vertical heterostructure is developed as TCEs for high-performance OLEDs, by directly oxidizing the top layer of three-layer graphene films with ozone treatment. Such GO/G heterostructure electrodes show greatly improved optical transmittance, a large work function, high stability, and good compatibility with HIL materials (MoO3 in this work). Moreover, the conductivity of the heterostructure is not sacrificed compared to the pristine three-layer graphene electrodes, but is significantly higher than that of pristine two-layer graphene films. In addition to high flexibility, OLEDs with different emission colors based on the GO/G heterostructure TCEs show much better performance than those based on indium tin oxide (ITO) anodes. Green OLEDs with GO/G heterostructure electrodes have the maximum current efficiency and power efficiency, as high as 82.0 cd A-1 and 98.2 lm W-1, respectively, which are 36.7% (14.8%) and 59.2% (15.0%) higher than those with pristine graphene (ITO) anodes. These findings open up the possibility of using graphene for next generation high-performance flexible and wearable optoelectronics with high stability.The relatively high sheet resistance, low work function and poor compatibility with hole injection layers (HILs) seriously limit the applications of graphene as transparent conductive electrodes (TCEs) for organic light emitting diodes (OLEDs). Here, a graphene oxide/graphene (GO/G) vertical heterostructure is developed as TCEs for high-performance OLEDs, by directly oxidizing the top layer of three-layer graphene films with ozone treatment. Such GO/G heterostructure electrodes show greatly improved optical transmittance, a large work function, high stability, and good compatibility with HIL materials (MoO3 in this work). Moreover, the conductivity of the heterostructure is not sacrificed compared to the pristine three-layer graphene electrodes, but is significantly higher than that of pristine two-layer graphene films. In addition to high flexibility, OLEDs with different emission colors based on the GO/G heterostructure TCEs show much better performance than those based on indium tin oxide (ITO) anodes. Green OLEDs with GO/G heterostructure electrodes have the maximum current efficiency and power efficiency, as high as 82.0 cd A-1 and 98.2 lm W-1, respectively, which are 36.7% (14.8%) and 59.2% (15.0%) higher than those with pristine graphene (ITO) anodes. These findings open up the possibility of using graphene for next generation high-performance flexible and wearable optoelectronics with high stability. Electronic supplementary information (ESI) available: XPS spectra, Raman spectra, sheet resistance and transmittance of graphene films with different numbers of layers and different ozone treatment times, doping effect of MoO3 on graphene and GO/G electrodes, performance of green OLEDs with different graphene anodes, a movie showing the flexibility of device. See DOI: 10.1039/c6nr01649a

Efficiency at rest: magnetoencephalographic resting-state connectivity and individual differences in verbal working memory.

PubMed

del Río, David; Cuesta, Pablo; Bajo, Ricardo; García-Pacios, Javier; López-Higes, Ramón; del-Pozo, Francisco; Maestú, Fernando

2012-11-01

Inter-individual differences in cognitive performance are based on an efficient use of task-related brain resources. However, little is known yet on how these differences might be reflected on resting-state brain networks. Here we used Magnetoencephalography resting-state recordings to assess the relationship between a behavioral measurement of verbal working memory and functional connectivity as measured through Mutual Information. We studied theta (4-8 Hz), low alpha (8-10 Hz), high alpha (10-13 Hz), low beta (13-18 Hz) and high beta (18-30 Hz) frequency bands. A higher verbal working memory capacity was associated with a lower mutual information in the low alpha band, prominently among right-anterior and left-lateral sensors. The results suggest that an efficient brain organization in the domain of verbal working memory might be related to a lower resting-state functional connectivity across large-scale brain networks possibly involving right prefrontal and left perisylvian areas. Copyright © 2012 Elsevier B.V. All rights reserved.

Cooptimization of Adhesion and Power Conversion Efficiency of Organic Solar Cells by Controlling Surface Energy of Buffer Layers.

PubMed

Lee, Inhwa; Noh, Jonghyeon; Lee, Jung-Yong; Kim, Taek-Soo

2017-10-25

Here, we demonstrate the cooptimization of the interfacial fracture energy and power conversion efficiency (PCE) of poly[N-9'-heptadecanyl-2,7-carbazole-alt-5,5-(4',7'-di-2-thienyl-2',1',3'-benzothiadiazole)] (PCDTBT)-based organic solar cells (OSCs) by surface treatments of the buffer layer. The investigated surface treatments of the buffer layer simultaneously changed the crack path and interfacial fracture energy of OSCs under mechanical stress and the work function of the buffer layer. To investigate the effects of surface treatments, the work of adhesion values were calculated and matched with the experimental results based on the Owens-Wendt model. Subsequently, we fabricated OSCs on surface-treated buffer layers. In particular, ZnO layers treated with poly[(9,9-bis(3'-(N,N-dimethylamino)propyl)-2,7-fluorene)-alt-2,7-(9,9-dioctylfluorene)] (PFN) simultaneously satisfied the high mechanical reliability and PCE of OSCs by achieving high work of adhesion and optimized work function.

Expanding Knowledge Gaps: The Function of Fictions in Teaching Materials after the 2011 Swedish High School Reform

ERIC Educational Resources Information Center

Graeske, Caroline

2016-01-01

The aim in the study is to analyze how work with fiction is organized in six textbooks for senior high school in Sweden after the school reform 2011. Research into Swedish teaching materials has been neglected in recent years and there is a knowledge gap about how the work with fictions is affected by the reform in 2011. In the study quantitative…

Morse oscillator propagator in the high temperature limit I: Theory

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

Toutounji, Mohamad, E-mail: Mtoutounji@uaeu.ac.ae

2017-02-15

In an earlier work of the author the time evolution of Morse oscillator was studied analytically and exactly at low temperatures whereupon optical correlation functions were calculated using Morse oscillator coherent states were employed. Morse oscillator propagator in the high temperature limit is derived and a closed form of its corresponding canonical partition function is obtained. Both diagonal and off-diagonal forms of Morse oscillator propagator are derived in the high temperature limit. Partition functions of diatomic molecules are calculated. - Highlights: • Derives the quantum propagator of Morse oscillator in the high temperature limit. • Uses the resulting diagonal propagatormore » to derive a closed form of Morse oscillator partition function. • Provides a more sophisticated formula of the quantum propagator to test the accuracy of the herein results.« less

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.

Structural and functional rich club organization of the brain in children and adults.

PubMed

Grayson, David S; Ray, Siddharth; Carpenter, Samuel; Iyer, Swathi; Dias, Taciana G Costa; Stevens, Corinne; Nigg, Joel T; Fair, Damien A

2014-01-01

Recent studies using Magnetic Resonance Imaging (MRI) have proposed that the brain's white matter is organized as a rich club, whereby the most highly connected regions of the brain are also highly connected to each other. Here we use both functional and diffusion-weighted MRI in the human brain to investigate whether the rich club phenomena is present with functional connectivity, and how this organization relates to the structural phenomena. We also examine whether rich club regions serve to integrate information between distinct brain systems, and conclude with a brief investigation of the developmental trajectory of rich-club phenomena. In agreement with prior work, both adults and children showed robust structural rich club organization, comprising regions of the superior medial frontal/dACC, medial parietal/PCC, insula, and inferior temporal cortex. We also show that these regions were highly integrated across the brain's major networks. Functional brain networks were found to have rich club phenomena in a similar spatial layout, but a high level of segregation between systems. While no significant differences between adults and children were found structurally, adults showed significantly greater functional rich club organization. This difference appeared to be driven by a specific set of connections between superior parietal, insula, and supramarginal cortex. In sum, this work highlights the existence of both a structural and functional rich club in adult and child populations with some functional changes over development. It also offers a potential target in examining atypical network organization in common developmental brain disorders, such as ADHD and Autism.

Functional Assessment to Predict Capacity for Work in a Population of School-Leavers with Disabilities

ERIC Educational Resources Information Center

Eagar, Kathy; Green, Janette; Gordon, Robert; Owen, Alan; Masso, Malcolm; Williams, Kathryn

2006-01-01

This study reports on an assessment system for school-leavers with disabilities to identify their capacity for work and the type of transition-to-work programme best suited to each person. Participants were 1,556 high school students in four cohorts who left school between 1999 and 2002. Each school-leaver was assessed by rehabilitation…

College Students with High-Functioning Autism Spectrum Disorder: Best Practices for Successful Transition to the World of Work

ERIC Educational Resources Information Center

Dipeolu, Abiola O.; Storlie, Cassandra; Johnson, Carol

2015-01-01

The transition from college to work is a challenging time for students with autism spectrum disorder. College counselors who understand the challenges students face adjusting to the world of work can position themselves to be change agents for this population. This article illuminates the challenges facing these students to help close the…

Research on AutoCAD secondary development and function expansion based on VBA technology

NASA Astrophysics Data System (ADS)

Zhang, Runmei; Gu, Yehuan

2017-06-01

AutoCAD is the most widely used drawing tool among the similar design drawing products. In the process of drawing different types of design drawings of the same product, there are a lot of repetitive and single work contents. The traditional manual method uses a drawing software AutoCAD drawing graphics with low efficiency, high error rate and high input cost shortcomings and many more. In order to solve these problems, the design of the parametric drawing system of the hot-rolled I-beam (steel beam) cross-section is completed by using the VBA secondary development tool and the Access database software with large-capacity storage data, and the analysis of the functional extension of the plane drawing and the parametric drawing design in this paper. For the secondary development of AutoCAD functions, the system drawing work will be simplified and work efficiency also has been greatly improved. This introduction of parametric design of AutoCAD drawing system to promote the industrial mass production and related industries economic growth rate similar to the standard I-beam hot-rolled products.

Everyday Functioning and Cognitive Correlates in Healthy Older Adults with Subjective Cognitive Concerns

PubMed Central

McAlister, Courtney; Schmitter-Edgecombe, Maureen

2016-01-01

Objective Few studies have examined functional abilities and complaints in healthy older adults with subjective cognitive concerns (SCC). The aims of this study were to assess everyday functioning in healthy older adults reporting high and low amounts of SCC, and examine cognitive correlates of functional abilities. Method Twenty-six healthy older adults with high SCC, and 25 healthy older adults with low SCC, as well as their knowledgeable informants completed the Instrumental Activities of Daily Living-Compensation (IADL-C), a questionnaire measure of everyday functioning. Results After controlling for depression, the high SCC group self-reported significantly more everyday difficulties on the IADL-C, including all subdomains. Compared to the low SCC group, informants for the high SCC group endorsed more difficulties on the IADL-C and specifically the social skills subdomain. For the high SCC group, poorer self-report of everyday functioning was related to poorer executive functioning and temporal order memory. Conclusions These findings indicate that there may be subtle functional changes that occur early in the spectrum of cognitive decline in individuals with high SCC, and these functional changes are evident to informants. Further work is needed to investigate whether individuals with both SCC and functional difficulties are at an even higher risk for progression to mild cognitive impairment. PMID:27240886

Topological Properties of Some Integrated Circuits for Very Large Scale Integration Chip Designs

NASA Astrophysics Data System (ADS)

Swanson, S.; Lanzerotti, M.; Vernizzi, G.; Kujawski, J.; Weatherwax, A.

2015-03-01

This talk presents topological properties of integrated circuits for Very Large Scale Integration chip designs. These circuits can be implemented in very large scale integrated circuits, such as those in high performance microprocessors. Prior work considered basic combinational logic functions and produced a mathematical framework based on algebraic topology for integrated circuits composed of logic gates. Prior work also produced an historically-equivalent interpretation of Mr. E. F. Rent's work for today's complex circuitry in modern high performance microprocessors, where a heuristic linear relationship was observed between the number of connections and number of logic gates. This talk will examine topological properties and connectivity of more complex functionally-equivalent integrated circuits. The views expressed in this article are those of the author and do not reflect the official policy or position of the United States Air Force, Department of Defense or the U.S. Government.

An internal variable constitutive model for the large deformation of metals at high temperatures

NASA Technical Reports Server (NTRS)

Brown, Stuart; Anand, Lallit

1988-01-01

The advent of large deformation finite element methodologies is beginning to permit the numerical simulation of hot working processes whose design until recently has been based on prior industrial experience. Proper application of such finite element techniques requires realistic constitutive equations which more accurately model material behavior during hot working. A simple constitutive model for hot working is the single scalar internal variable model for isotropic thermal elastoplasticity proposed by Anand. The model is recalled and the specific scalar functions, for the equivalent plastic strain rate and the evolution equation for the internal variable, presented are slight modifications of those proposed by Anand. The modified functions are better able to represent high temperature material behavior. The monotonic constant true strain rate and strain rate jump compression experiments on a 2 percent silicon iron is briefly described. The model is implemented in the general purpose finite element program ABAQUS.

Effectiveness of family work interventions on schizophrenia: evidence from a multicentre study in Catalonia.

PubMed

Tomás, Esther Pousa; Hurtado, Gemma; Noguer, Sílvia; Domènech, Cristina; García, Montse; López, Nuria; Negredo, Maríacruz; Penadés, Rafael; Reinares, María; Serrano, Dolors; Dolz, Montse; Gallo, Pedro

2012-11-01

Despite their proven efficacy, family work interventions on families of patients with schizophrenia are not being implemented in routine clinical practice in contexts where expressed emotion levels among caregivers are relatively high. This study aimed to explore the effectiveness of a family work intervention in a Mediterranean environment in Catalonia, Spain. Participants were 23 patients and 35 key relatives in five different clinical settings. The family intervention was provided by 10 trained health care professionals during a nine-month period. A six-month follow-up was also conducted. Statistically significant improvements were found in patients' clinical status, global functioning and social functioning levels, as well as in caregivers' burden of care. These results were maintained during follow-up. This is the first study to explore the effectiveness of family intervention in a high-expressed emotion context in Catalonia. The findings add weight to the growing literature supporting these interventions in different cultural settings.

Possibilities of the ErgoScope high fidelity work simulator in skill assessment, skill development and vocational aptitude tests of physically disabled persons.

PubMed

Izsó, Lajos; Székely, Ildikó; Dános, László

2015-01-01

The aim of this paper - based on the extensive experiences of the authors gained by using one particular work simulator - is to present some promising possibilities of the application of this (and any other similar) work simulator in the field of skill assessment, skill development and vocational aptitude tests of physically disabled persons. During skill assessment and development, as parts of the therapy, the focus is on the disabled functions. During vocational aptitude tests, however, the focus is already on the functions that remained intact and therefore can be the basis of returning to work. Some factual examples are provided to realize the proposed possibilities in practice.

Effects of tennis play on executive function in 6-11-year-old children: a 12-month longitudinal study.

PubMed

Ishihara, Toru; Mizuno, Masao

2018-06-01

The present study aimed to assess the effects of 12 months of frequent tennis play on executive functions and the relationships of daily moderate-to-vigorous physical activity (MVPA), physical competence, and enjoyment of playing tennis to executive functions in children. Thirty-two children (6-11 years old) who had regularly played tennis (once a week; mean = 3 years, range = 0-6 years) before the study were enrolled in a 12-month intervention. Participants were allocated into two groups: low-dose (maintain current frequency of tennis play, N = 19) or high-dose (increased frequency of tennis play to four times per week, N = 13). Participants' MVPA, physical competence, enjoyment of playing tennis, and executive functions (i.e. inhibitory control, working memory, and cognitive flexibility) were evaluated before and after this intervention. The high-dose group demonstrated a greater improvement in working memory than the low-dose group, while there was no group difference in MVPA, physical competence, and enjoyment of playing tennis. Changes in MVPA were associated with improvements in cognitive flexibility. Changes in physical competence were associated with improvements in working memory and cognitive flexibility. Changes in the enjoyment of playing tennis were associated with improvements in inhibitory control. The current findings suggest that replacement of MVPA with sports activity, such as tennis enhances executive functions development, and suggest that sports programmes that seek to build competence and enjoyment might help support the development of executive functions in children.

Focusing on attention: the effects of working memory capacity and load on selective attention.

PubMed

Ahmed, Lubna; de Fockert, Jan W

2012-01-01

Working memory (WM) is imperative for effective selective attention. Distractibility is greater under conditions of high (vs. low) concurrent working memory load (WML), and in individuals with low (vs. high) working memory capacity (WMC). In the current experiments, we recorded the flanker task performance of individuals with high and low WMC during low and high WML, to investigate the combined effect of WML and WMC on selective attention. In Experiment 1, distractibility from a distractor at a fixed distance from the target was greater when either WML was high or WMC was low, but surprisingly smaller when both WML was high and WMC low. Thus we observed an inverted-U relationship between reductions in WM resources and distractibility. In Experiment 2, we mapped the distribution of spatial attention as a function of WMC and WML, by recording distractibility across several target-to-distractor distances. The pattern of distractor effects across the target-to-distractor distances demonstrated that the distribution of the attentional window becomes dispersed as WM resources are limited. The attentional window was more spread out under high compared to low WML, and for low compared to high WMC individuals, and even more so when the two factors co-occurred (i.e., under high WML in low WMC individuals). The inverted-U pattern of distractibility effects in Experiment 1, replicated in Experiment 2, can thus be explained by differences in the spread of the attentional window as a function of WM resource availability. The current findings show that limitations in WM resources, due to either WML or individual differences in WMC, affect the spatial distribution of attention. The difference in attentional constraining between high and low WMC individuals demonstrated in the current experiments helps characterise the nature of previously established associations between WMC and controlled attention.

Rhodium-catalyzed C-H functionalization with N-acylsaccharins.

PubMed

Wu, Hongxiang; Liu, Tingting; Cui, Ming; Li, Yue; Jian, Junsheng; Wang, Hui; Zeng, Zhuo

2017-01-18

A rhodium-catalyzed C-H functionalization with activated amides by decarbonylation has been developed. Notably, this is the first C-H arylation employing N-acylsaccharins as coupling partners to give biaryls in good to excellent yields. The highlight of the work is the high tolerance of functional groups such as formyl, ester, and vinyl and the use of a removable directing group.

Evolution of High Mobility Group Nucleosome-Binding Proteins and Its Implications for Vertebrate Chromatin Specialization

PubMed Central

González-Romero, Rodrigo; Eirín-López, José M.; Ausió, Juan

2015-01-01

High mobility group (HMG)-N proteins are a family of small nonhistone proteins that bind to nucleosomes (N). Despite the amount of information available on their structure and function, there is an almost complete lack of information on the molecular evolutionary mechanisms leading to their exclusive differentiation. In the present work, we provide evidence suggesting that HMGN lineages constitute independent monophyletic groups derived from a common ancestor prior to the diversification of vertebrates. Based on observations of the functional diversification across vertebrate HMGN proteins and on the extensive silent nucleotide divergence, our results suggest that the long-term evolution of HMGNs occurs under strong purifying selection, resulting from the lineage-specific functional constraints of their different protein domains. Selection analyses on independent lineages suggest that their functional specialization was mediated by bursts of adaptive selection at specific evolutionary times, in a small subset of codons with functional relevance—most notably in HMGN1, and in the rapidly evolving HMGN5. This work provides useful information to our understanding of the specialization imparted on chromatin metabolism by HMGNs, especially on the evolutionary mechanisms underlying their functional differentiation in vertebrates. PMID:25281808

Cytoskeleton Molecular Motors: Structures and Their Functions in Neuron.

PubMed

Xiao, Qingpin; Hu, Xiaohui; Wei, Zhiyi; Tam, Kin Yip

2016-01-01

Cells make use of molecular motors to transport small molecules, macromolecules and cellular organelles to target region to execute biological functions, which is utmost important for polarized cells, such as neurons. In particular, cytoskeleton motors play fundamental roles in neuron polarization, extension, shape and neurotransmission. Cytoskeleton motors comprise of myosin, kinesin and cytoplasmic dynein. F-actin filaments act as myosin track, while kinesin and cytoplasmic dynein move on microtubules. Cytoskeleton motors work together to build a highly polarized and regulated system in neuronal cells via different molecular mechanisms and functional regulations. This review discusses the structures and working mechanisms of the cytoskeleton motors in neurons.

Modality Specificity and Integration in Working Memory: Insights from Visuospatial Bootstrapping

ERIC Educational Resources Information Center

Allen, Richard J.; Havelka, Jelena; Falcon, Thomas; Evans, Sally; Darling, Stephen

2015-01-01

The question of how meaningful associations between verbal and spatial information might be utilized to facilitate working memory performance is potentially highly instructive for models of memory function. The present study explored how separable processing capacities within specialized domains might each contribute to this, by examining the…

Artistic Works for Children.

ERIC Educational Resources Information Center

Cieslikowski, Jerzy

This paper discusses the nature and function of children's literature and theater. Artistic creative work for children is constituted not only by literature but also by the theater, film, radio and television. Children's literature used to be an art of narration, a verbal text coupled with gesture. Modern, highly technical communication media have…

Simple mechanism whereby the F1-ATPase motor rotates with near-perfect chemomechanical energy conversion

PubMed Central

Saita, Ei-ichiro; Suzuki, Toshiharu; Kinosita, Kazuhiko; Yoshida, Masasuke

2015-01-01

F1-ATPase is a motor enzyme in which a central shaft γ subunit rotates 120° per ATP in the cylinder made of α3β3 subunits. During rotation, the chemical energy of ATP hydrolysis (ΔGATP) is converted almost entirely into mechanical work by an elusive mechanism. We measured the force for rotation (torque) under various ΔGATP conditions as a function of rotation angles of the γ subunit with quasi-static, single-molecule manipulation and estimated mechanical work (torque × traveled angle) from the area of the function. The torque functions show three sawtooth-like repeats of a steep jump and linear descent in one catalytic turnover, indicating a simple physical model in which the motor is driven by three springs aligned along a 120° rotation angle. Although the second spring is unaffected by ΔGATP, activation of the first spring (timing of the torque jump) delays at low [ATP] (or high [ADP]) and activation of the third spring delays at high [Pi]. These shifts decrease the size and area of the sawtooth (magnitude of the work). Thus, F1-ATPase responds to the change of ΔGATP by shifting the torque jump timing and uses ΔGATP for the mechanical work with near-perfect efficiency. PMID:26195785

Working memory training improves emotion regulation ability: Evidence from HRV.

PubMed

Xiu, Lichao; Zhou, Renlai; Jiang, Yihan

2016-03-01

Emotion regulation during social situations plays a pivotal role in health and interpersonal functioning. In this study, we propose a working memory training approach to improve emotion regulation ability. This training promotes an updating function that is a crucial modulated process for emotion regulation. In the present study, the participants in the training group completed a running memory task over 20 days of training. Their working memory capability and high-frequency heart rate variability (HF-HRV) data on pretest and posttest were assessed and analyzed. Compared with the control group, the training group's reaction time in the 2-back working memory task was reduced significantly. In addition, the HF-HRV in the emotion regulation condition was increased after the 20-day training, which indicates that the working memory training effect could transfer to emotion regulation. In other words, working memory training improved emotion regulation ability. Copyright © 2015 Elsevier Inc. All rights reserved.

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.

Self Esteem, Information Search and Problem Solving Efficiency.

DTIC Science & Technology

1979-05-01

Weiss (1977, 1978) has shown that low self esteem workers are more likely to model the role behaviors and work values of superiors than are high self ...task where search is functional. Results showed that, as expected, low self esteem subjects searched for more information, search was functional and low ...situation. He has also argued that high self esteem individuals search for less information on problem solving tasks and are therefore less likely to

Data Modeling Using Finite Differences

ERIC Educational Resources Information Center

Rhoads, Kathryn; Mendoza Epperson, James A.

2017-01-01

The Common Core State Standards for Mathematics (CCSSM) states that high school students should be able to recognize patterns of growth in linear, quadratic, and exponential functions and construct such functions from tables of data (CCSSI 2010). In their work with practicing secondary teachers, the authors found that teachers may make some tacit…

Chlorinated indium tin oxide electrode by InCl{sub 3} aqueous solution for high-performance organic light-emitting diodes

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

Hu, Yun; Wang, Bo; Wang, Zhao-Kui, E-mail: zkwang@suda.edu.cn, E-mail: lsliao@suda.edu.cn

2016-04-11

The authors develop a facile and effective method to produce the chlorinated indium tin oxide (Cl-ITO) treated by InCl{sub 3} aqueous solution and UV/ozone. The work function of the Cl-ITO achieved by this treatment is as high as 5.69 eV, which is increased by 1.09 eV compared with that of the regular ITO without any treatment. Further investigation proved that the enhancement of the work function is attributed to the formation of In-Cl bonds on the Cl-ITO surface. Green phosphorescent organic light-emitting devices based on the Cl-ITO electrodes exhibit excellent electroluminescence performance, elongating lifetime due to the improvement in hole injection.

Functional insights from proteome-wide structural modeling of Treponema pallidum subspecies pallidum, the causative agent of syphilis.

PubMed

Houston, Simon; Lithgow, Karen Vivien; Osbak, Kara Krista; Kenyon, Chris Richard; Cameron, Caroline E

2018-05-16

Syphilis continues to be a major global health threat with 11 million new infections each year, and a global burden of 36 million cases. The causative agent of syphilis, Treponema pallidum subspecies pallidum, is a highly virulent bacterium, however the molecular mechanisms underlying T. pallidum pathogenesis remain to be definitively identified. This is due to the fact that T. pallidum is currently uncultivatable, inherently fragile and thus difficult to work with, and phylogenetically distinct with no conventional virulence factor homologs found in other pathogens. In fact, approximately 30% of its predicted protein-coding genes have no known orthologs or assigned functions. Here we employed a structural bioinformatics approach using Phyre2-based tertiary structure modeling to improve our understanding of T. pallidum protein function on a proteome-wide scale. Phyre2-based tertiary structure modeling generated high-confidence predictions for 80% of the T. pallidum proteome (780/978 predicted proteins). Tertiary structure modeling also inferred the same function as primary structure-based annotations from genome sequencing pipelines for 525/605 proteins (87%), which represents 54% (525/978) of all T. pallidum proteins. Of the 175 T. pallidum proteins modeled with high confidence that were not assigned functions in the previously annotated published proteome, 167 (95%) were able to be assigned predicted functions. Twenty-one of the 175 hypothetical proteins modeled with high confidence were also predicted to exhibit significant structural similarity with proteins experimentally confirmed to be required for virulence in other pathogens. Phyre2-based structural modeling is a powerful bioinformatics tool that has provided insight into the potential structure and function of the majority of T. pallidum proteins and helped validate the primary structure-based annotation of more than 50% of all T. pallidum proteins with high confidence. This work represents the first T. pallidum proteome-wide structural modeling study and is one of few studies to apply this approach for the functional annotation of a whole proteome.

A functional promoter variant of the human formimidoyltransferase cyclodeaminase (FTCD) gene is associated with working memory performance in young but not older adults.

PubMed

Greenwood, Pamela M; Schmidt, Kevin; Lin, Ming-Kuan; Lipsky, Robert; Parasuraman, Raja; Jankord, Ryan

2018-06-21

The central role of working memory in IQ and the high heritability of working memory performance motivated interest in identifying the specific genes underlying this heritability. The FTCD (formimidoyltransferase cyclodeaminase) gene was identified as a candidate gene for allelic association with working memory in part from genetic mapping studies of mouse Morris water maze performance. The present study tested variants of this gene for effects on a delayed match-to-sample task of a large sample of younger and older participants. The rs914246 variant, but not the rs914245 variant, of the FTCD gene modulated accuracy in the task for younger, but not older, people under high working memory load. The interaction of haplotype × distance × load had a partial eta squared effect size of 0.015. Analysis of simple main effects had partial eta squared effect sizes ranging from 0.012 to 0.040. A reporter gene assay revealed that the C allele of the rs914246 genotype is functional and a main factor regulating FTCD gene expression. This study extends previous work on the genetics of working memory by revealing that a gene in the glutamatergic pathway modulates working memory in young people but not in older people. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

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.

M18. Lack of Generalization From a High-Dose, Well-Powered Randomized Controlled Trial of Working Memory-Focused Training for Schizophrenia

PubMed Central

Nienow, Tasha; MacDonald, Angus

2017-01-01

Abstract Background: Cognitive deficits contribute to the functional disability associated with schizophrenia. Cognitive training has shown promise as a method of intervention; however, there is considerable variability in the implementation of this approach. The aim of this study was to test the efficacy of a high dose of cognitive training that targeted working memory-related functions. Methods: A randomized, double blind, active placebo-controlled, clinical trial was conducted with 80 outpatients with schizophrenia (mean age 46.44 years, 25% female). Patients were randomized to either working memory-based cognitive training or a computer skills training course that taught computer applications. In both conditions, participants received an average of 3 hours of training weekly for 16 weeks. Cognitive and functional outcomes were assessed with the MATRICS Consensus Cognitive Battery, N-Back performance, 2 measures of functional capacity (UPSA and SSPA) and a measure of community functioning, the Social Functioning Scale. Results: An intent-to-treat analysis found that patients who received cognitive training demonstrated significantly greater change on a trained task (Word N-Back), F(78) = 21.69, P < .0001, and a novel version of a trained task (Picture N-Back) as compared to those in the comparison condition, F(78) = 13.59, P = .002. However, only very modest support was found for generalization of training gains. A trend for an interaction was found on the MCCB Attention Domain score, F(78) = 2.56, P = .12. Participants who received cognitive training demonstrated significantly improved performance, t(39) = 3.79, P = .001, while those in computer skills did not, t(39) = 1.07, P = .37. Conclusion: A well-powered, high-dose, working memory focused, computer-based, cognitive training protocol produced only a small effect in patients with schizophrenia. Results indicate the importance of measuring generalization from training tasks in cognitive remediation studies. Computer-based training was not an effective method of producing change in cognition in patients with schizophrenia.

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.

Functional brain microstate predicts the outcome in a visuospatial working memory task.

PubMed

Muthukrishnan, Suriya-Prakash; Ahuja, Navdeep; Mehta, Nalin; Sharma, Ratna

2016-11-01

Humans have limited capacity of processing just up to 4 integrated items of information in the working memory. Thus, it is inevitable to commit more errors when challenged with high memory loads. However, the neural mechanisms that determine the accuracy of response at high memory loads still remain unclear. High temporal resolution of Electroencephalography (EEG) technique makes it the best tool to resolve the temporal dynamics of brain networks. EEG-defined microstate is the quasi-stable scalp electrical potential topography that represents the momentary functional state of brain. Thus, it has been possible to assess the information processing currently performed by the brain using EEG microstate analysis. We hypothesize that the EEG microstate preceding the trial could determine its outcome in a visuospatial working memory (VSWM) task. Twenty-four healthy participants performed a high memory load VSWM task, while their brain activity was recorded using EEG. Four microstate maps were found to represent the functional brain state prior to the trials in the VSWM task. One pre-trial microstate map was found to determine the accuracy of subsequent behavioural response. The intracranial generators of the pre-trial microstate map that determined the response accuracy were localized to the visuospatial processing areas at bilateral occipital, right temporal and limbic cortices. Our results imply that the behavioural outcome in a VSWM task could be determined by the intensity of activation of memory representations in the visuospatial processing brain regions prior to the trial. Copyright © 2016 Elsevier B.V. All rights reserved.

The effect of obturator bulb height on speech in maxillectomy patients.

PubMed

Kwon, H B; Chang, S W; Lee, S H

2011-03-01

The purpose of this study was to compare the speech function of low height bulb obturators with that of high height bulb obturators. Thirteen maxillectomy patients, who underwent post-operative prosthodontic rehabilitations, were included. Two obturators of the same design except for different bulb heights were fabricated for each maxillectomy patient. One of the two obturators had high bulb design and the other had low bulb design. After one of the obturators was used for a period of 3 weeks, the patient's speaking functions were evaluated by measuring nasalance scores, formant frequencies, and vowel working space areas. The same procedures were repeated with the second obturator following another 3-week period of usage. In addition, the effect of delivery sequence and anatomic conditions related to maxillectomy were analysed. The results demonstrated that the nasalance scores with the low bulb obturators were significantly higher than those with the high bulb obturators. There were no significant differences in formant frequencies based on the bulb height of the obturators. The vowel working spaces for the two obturators were similar in shape and there were no significant differences between the vowel working space areas created by the two obturators. The delivery sequence affected the results. However, there were no significant differences related to the other anatomical variables. Although low bulb obturators might function similarly with high bulb obturators in terms of the articulation of speech, they would exhibit a difficulty in controlling hypernasality in maxillectomy patients. © 2010 Blackwell Publishing Ltd.

Factors that promote or hinder young disabled people in work participation: a systematic review.

PubMed

Achterberg, T J; Wind, H; de Boer, A G E M; Frings-Dresen, M H W

2009-06-01

The aim of this systematic review was to study factors which promote or hinder young disabled people entering the labor market. We systematically searched PubMed (by means of MESH and text words), EMBASE, PsycINFO, Web of Science and CINAHL for studies regarding (1) disabled patients diagnosed before the age of 18 years and (2) factors of work participation. Out of 1,268 retrieved studies and 28 extended studies from references and four from experts, ten articles were included. Promoting factors are male gender, high educational level, age at survey, low depression scores, high dispositional optimism and high psychosocial functioning. Female and low educational level gives high odds of unemployment just like low IQ, inpatient treatment during follow up, epilepsy, motor impairment, wheelchair dependency, functional limitations, co-morbidity, physical disability and chronic health conditions combined with mental retardation. High dose cranial radiotherapy, type of cancer, and age of diagnosis also interfered with employment. Of the promoting factors, education appeared to be important, and several physical obstructions were found to be hindering factors. The last mentioned factors can be influenced in contrast to for instance age and gender. However, to optimize work participation of this group of young disabled it is important to know the promoting or hindering influence for employment.

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.

Respiratory symptoms and lung function in relation to wood dust and monoterpene exposure in the wood pellet industry.

PubMed

Löfstedt, Håkan; Hagström, Katja; Bryngelsson, Ing-Liss; Holmström, Mats; Rask-Andersen, Anna

2017-06-01

Wood pellets are used as a source of renewable energy for heating purposes. Common exposures are wood dust and monoterpenes, which are known to be hazardous for the airways. The purpose of this study was to study the effect of occupational exposure on respiratory health in wood pellet workers. Thirty-nine men working with wood pellet production at six plants were investigated with a questionnaire, medical examination, allergy screening, spirometry, and nasal peak expiratory flow (nasal PEF). Exposure to wood dust and monoterpenes was measured. The wood pellet workers reported a higher frequency of nasal symptoms, dry cough, and asthma medication compared to controls from the general population. There were no differences in nasal PEF between work and leisure time. A lower lung function than expected (vital capacity [VC], 95%; forced vital capacity in 1 second [FEV 1 ], 96% of predicted) was noted, but no changes were noted during shifts. There was no correlation between lung function and years working in pellet production. Personal measurements of wood dust at work showed high concentrations (0.16-19 mg/m 3 ), and exposure peaks when performing certain work tasks. Levels of monoterpenes were low (0.64-28 mg/m 3 ). There was no association between exposure and acute lung function effects. In this study of wood pellet workers, high levels of wood dust were observed, and that may have influenced the airways negatively as the study group reported upper airway symptoms and dry cough more frequently than expected. The wood pellet workers had both a lower VC and FEV 1 than expected. No cross-shift changes were found.

Respiratory symptoms and lung function in relation to wood dust and monoterpene exposure in the wood pellet industry

PubMed Central

Löfstedt, Håkan; Hagström, Katja; Bryngelsson, Ing-Liss; Holmström, Mats; Rask-Andersen, Anna

2017-01-01

Introduction Wood pellets are used as a source of renewable energy for heating purposes. Common exposures are wood dust and monoterpenes, which are known to be hazardous for the airways. The purpose of this study was to study the effect of occupational exposure on respiratory health in wood pellet workers. Materials and methods Thirty-nine men working with wood pellet production at six plants were investigated with a questionnaire, medical examination, allergy screening, spirometry, and nasal peak expiratory flow (nasal PEF). Exposure to wood dust and monoterpenes was measured. Results The wood pellet workers reported a higher frequency of nasal symptoms, dry cough, and asthma medication compared to controls from the general population. There were no differences in nasal PEF between work and leisure time. A lower lung function than expected (vital capacity [VC], 95%; forced vital capacity in 1 second [FEV1], 96% of predicted) was noted, but no changes were noted during shifts. There was no correlation between lung function and years working in pellet production. Personal measurements of wood dust at work showed high concentrations (0.16–19 mg/m3), and exposure peaks when performing certain work tasks. Levels of monoterpenes were low (0.64–28 mg/m3). There was no association between exposure and acute lung function effects. Conclusions In this study of wood pellet workers, high levels of wood dust were observed, and that may have influenced the airways negatively as the study group reported upper airway symptoms and dry cough more frequently than expected. The wood pellet workers had both a lower VC and FEV1 than expected. No cross-shift changes were found. PMID:28276782

Health-related quality of life in children with high-functioning autism.

PubMed

Potvin, Marie-Christine; Snider, Laurie; Prelock, Patricia A; Wood-Dauphinee, Sharon; Kehayia, Eva

2015-01-01

The health-related quality of life of school-aged children with high-functioning autism is poorly understood. The objectives of this study were to compare the health-related quality of life of children with high-functioning autism to that of typically developing peers and to compare child-self and parent-proxy reports of health-related quality of life of children. A cross-sectional study of children with high-functioning autism (n = 30) and peers (n = 31) was conducted using the Pediatric Quality of Life Inventory 4.0 Generic Core Scales. Children with high-functioning autism had significantly poorer health-related quality of life than peers whether reported by themselves (p < .001) or their parents (p < .001), although disagreement (intra-class coefficient = -.075) between children and parental scores suggested variance in points of view. This study specifically investigated health-related quality of life in children with high-functioning autism as compared to a sample of peers, from the child's perspective. It strengthens earlier findings that children with high-functioning autism experience poorer health-related quality of life than those without this disorder and points to the importance of clinicians working with families to identify areas in a child's life that promote or hinder their sense of well-being. © The Author(s) 2013.

Electrical characterization of fluorinated benzothiadiazole based conjugated copolymer - a promising material for high-performance solar cells

NASA Astrophysics Data System (ADS)

Toušek, J.; Toušková, J.; Remeš, Z.; Chomutová, R.; Čermák, J.; Helgesen, M.; Carlé, J. E.; Krebs, F. C.

2015-12-01

Measurements of electrical conductivity, electron work function, carrier mobility of holes and the diffusion length of excitons were performed on samples of conjugated polymers relevant to polymer solar cells. A state of the art fluorinated benzothiadiazole based conjugated copolymer (PBDTTHD - DTBTff) was studied and benchmarked against the reference polymer poly-3-hexylthiophene (P3HT). We employed, respectively, four electrode conductivity measurements, Kelvin probe work function measurements, carrier mobility using charge extraction by linearly increasing voltage (CELIV) measurements and diffusion length determinaton using surface photovoltage measurements.

Literacy in the Work Force. Report Number 947.

ERIC Educational Resources Information Center

Lund, Leonard; McGuire, E. Patrick

Up to 10 percent of U.S. workers are either functionally illiterate or marginally literate. These workers increase the operational costs of their employers and restrain companies' flexibility. The high school graduates of the 1990s will exacerbate the problem by entering the work force with marginal literacy skills. A survey of 1,600 manufacturing…

Fostering Positive Youth Development through Work-Based Learning: The Cristo Rey Model

ERIC Educational Resources Information Center

Bempechat, Janine; Kenny, Maureen; Blustein, David L.; Seltzer, Joanne

2014-01-01

This chapter presents findings of a three-year longitudinal study of academic motivation and school engagement among low-income high school students enrolled in a corporate work-study program. Our findings demonstrate ways in which the workplace functioned for students as a conduit of emotional resources, offering instrumental support from caring…

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.

Content Area Reading: A Functional Approach.

ERIC Educational Resources Information Center

Plecki, Gerard D.

The implementation of a content reading program at Urbana High School, Urbana, Illinois, is discussed in this document. Reading staff hired with Title VII funds offered assistance to all teachers in the high school by working with classroom teachers in their classes for 60 minutes of class time per week. Free reading time devoted to high-interest…

The association of social functioning, social relationships and the receipt of compensation with time to return to work following unintentional injuries to Victorian workers.

PubMed

Clay, Fiona J; Fitzharris, Michael; Kerr, Emily; McClure, Roderick J; Watson, Wendy L

2012-09-01

Understanding individual factors associated with return to work (RTW) post-injury is an important goal of compensation systems research. The aim of the present study was to determine factors associated with time to return to work following acute unintentional injuries. A prospective cohort study was conducted in Victoria, Australia. The cohort comprised 133 persons who were employed at the time they were admitted to one of three study hospitals. Baseline health status data was obtained retrospectively at one-week post-injury and participants were further surveyed at 1, 6, 12, 26 and 52 weeks post-injury to measure recovery. Multivariate Cox proportional hazards regression analysis was used to examine the association between potential prognostic factors and time to RTW during the 12 month study. At the end of 12 months follow-up, 81.2% of the study cohort had returned to work. Older age, increased injury severity, self reported symptomatic pain and poor mental health at 1 week post-injury were associated with extended time to RTW. A significant statistical interaction between the receipt of compensation and high social functioning as measured by the SF-36 or strong social relationships as measured by the Assessment of Quality of Life was associated with earlier RTW. Participants reporting strong social relationships and high social functioning at 1 week post-injury and entitled to injury compensation returned to work 2.05 and 3.66 times earlier respectively, than similar participants with no entitlement to compensation. Both injury-related and psychosocial factors were associated with the duration of time to RTW following acute unintentional injuries. This study replicated previously reported findings on social functioning and compensation from an independent acute trauma sample. Programs or policies to improve social functioning early post-injury may provide opportunities to improve the duration of time to RTW following injury.

MoOx modified ZnGaO based transparent conducting oxides

NASA Astrophysics Data System (ADS)

Dutta, Titas; Gupta, P.; Bhosle, V.; Narayan, J.

2009-03-01

We report here the growth of high work function bilayered structures of thin MoOx (2.0

Rhenium-phthalocyanine molecular nanojunction with high magnetic anisotropy and high spin filtering efficiency

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

Li, J.; Institute of Nanomaterial and Nanostructure, Changsha University of Science and Technology, Changsha 410114; Hu, J.

2015-07-20

Using the density functional and non-equilibrium Green's function approaches, we studied the magnetic anisotropy and spin-filtering properties of various transition metal-Phthalocyanine molecular junctions across two Au electrodes. Our important finding is that the Au-RePc-Au junction has both large spin filtering efficiency (>80%) and large magnetic anisotropy energy, which makes it suitable for device applications. To provide insights for the further experimental work, we discussed the correlation between the transport property, magnetic anisotropy, and wave function features of the RePc molecule, and we also illustrated the possibility of controlling its magnetic state.

ResourceCheck: Assess Your District's Resource Use

ERIC Educational Resources Information Center

Education Resource Strategies, 2013

2013-01-01

For over a decade, Education Resource Strategies, Inc. (ERS) has helped leaders of urban school districts strategically reallocate their resources to improve student performance. This work identifies seven Core Transformational Strategies that support high-performing schools; in high-functioning districts, resources (people, time, and money) are…

[The testing system for OCP of the digital X-ray machine].

PubMed

Wang, Yan; Mo, Guoming; Wang, Juru; Zhou, Tao; Yu, Jianguo

2011-09-01

In this paper, we designed a testing system for operator control panel of a high-voltage and high-frequency X-ray machine, and an online testing software for functional components, in order to help the testing engineers to improve their work efficiency.

Impact of neurocognition on social and role functioning in individuals at clinical high risk for psychosis.

PubMed

Carrión, Ricardo E; Goldberg, Terry E; McLaughlin, Danielle; Auther, Andrea M; Correll, Christoph U; Cornblatt, Barbara A

2011-08-01

Cognitive deficits have been well documented in schizophrenia and have been shown to impair quality of life and to compromise everyday functioning. Recent studies of adolescents and young adults at high risk for developing psychosis show that neurocognitive impairments are detectable before the onset of psychotic symptoms. However, it remains unclear how cognitive impairments affect functioning before the onset of psychosis. The authors assessed cognitive impairment in adolescents at clinical high risk for psychosis and examined its impact on social and role functioning. A sample of 127 treatment-seeking patients at clinical high risk for psychosis and a group of 80 healthy comparison subjects were identified and recruited for research in the Recognition and Prevention Program. At baseline, participants were assessed with a comprehensive neurocognitive battery as well as measures of social and role functioning. Relative to healthy comparison subjects, clinical high-risk patients showed significant impairments in the domains of processing speed, verbal memory, executive function, working memory, visuospatial processing, motor speed, sustained attention, and language. Clinical high-risk patients also displayed impaired social and role functioning at baseline. Among patients with attenuated positive symptoms, processing speed was related to social and role functioning at baseline. These findings demonstrate that cognitive and functional impairments are detectable in patients at clinical high risk for psychosis before the onset of psychotic illness and that processing speed appears to be an important cognitive predictor of poor functioning.

Impact of Neurocognition on Social and Role Functioning in Individuals at Clinical High Risk for Psychosis

PubMed Central

Carrión, Ricardo E.; Goldberg, Terry E.; McLaughlin, Danielle; Auther, Andrea M.; Correll, Christoph U.; Cornblatt, Barbara A.

2011-01-01

Objective Cognitive deficits have been well documented in schizophrenia and have been shown to impair quality of life and to compromise everyday functioning. Recent studies of adolescents and young adults at high risk for developing psychosis show that neurocognitive impairments are detectable before the onset of psychotic symptoms. However, it remains unclear how cognitive impairments affect functioning before the onset of psychosis. The authors assessed cognitive impairment in adolescents at clinical high risk for psychosis and examined its impact on social and role functioning. Method A sample of 127 treatment-seeking patients at clinical high risk for psychosis and a group of 80 healthy comparison subjects were identified and recruited for research in the Recognition and Prevention Program. At baseline, participants were assessed with a comprehensive neurocognitive battery as well as measures of social and role functioning. Results Relative to healthy comparison subjects, clinical high-risk patients showed significant impairments in the domains of processing speed, verbal memory, executive function, working memory, visuospatial processing, motor speed, sustained attention, and language. Clinical high-risk patients also displayed impaired social and role functioning at baseline. Among patients with attenuated positive symptoms, processing speed was related to social and role functioning at baseline. Conclusions These findings demonstrate that cognitive and functional impairments are detectable in patients at clinical high risk for psychosis before the onset of psychotic illness and that processing speed appears to be an important cognitive predictor of poor functioning. PMID:21536691

Decision Support System Requirements Definition for Human Extravehicular Activity Based on Cognitive Work Analysis

PubMed Central

Miller, Matthew James; McGuire, Kerry M.; Feigh, Karen M.

2016-01-01

The design and adoption of decision support systems within complex work domains is a challenge for cognitive systems engineering (CSE) practitioners, particularly at the onset of project development. This article presents an example of applying CSE techniques to derive design requirements compatible with traditional systems engineering to guide decision support system development. Specifically, it demonstrates the requirements derivation process based on cognitive work analysis for a subset of human spaceflight operations known as extravehicular activity. The results are presented in two phases. First, a work domain analysis revealed a comprehensive set of work functions and constraints that exist in the extravehicular activity work domain. Second, a control task analysis was performed on a subset of the work functions identified by the work domain analysis to articulate the translation of subject matter states of knowledge to high-level decision support system requirements. This work emphasizes an incremental requirements specification process as a critical component of CSE analyses to better situate CSE perspectives within the early phases of traditional systems engineering design. PMID:28491008

Decision Support System Requirements Definition for Human Extravehicular Activity Based on Cognitive Work Analysis.

PubMed

Miller, Matthew James; McGuire, Kerry M; Feigh, Karen M

2017-06-01

The design and adoption of decision support systems within complex work domains is a challenge for cognitive systems engineering (CSE) practitioners, particularly at the onset of project development. This article presents an example of applying CSE techniques to derive design requirements compatible with traditional systems engineering to guide decision support system development. Specifically, it demonstrates the requirements derivation process based on cognitive work analysis for a subset of human spaceflight operations known as extravehicular activity . The results are presented in two phases. First, a work domain analysis revealed a comprehensive set of work functions and constraints that exist in the extravehicular activity work domain. Second, a control task analysis was performed on a subset of the work functions identified by the work domain analysis to articulate the translation of subject matter states of knowledge to high-level decision support system requirements. This work emphasizes an incremental requirements specification process as a critical component of CSE analyses to better situate CSE perspectives within the early phases of traditional systems engineering design.

Ultrahigh-sensitive sensing platform based on p-type dumbbell-like Co3O4 network

NASA Astrophysics Data System (ADS)

Zhou, Tingting; Zhang, Tong; Zhang, Rui; Lou, Zheng; Deng, Jianan; Wang, Lili

2017-12-01

Development of high performance room temperature sensors remains a grand challenge for high demand of practical application. Metal oxide semiconductors (MOSs) have many advantages over others due to their easy functionalization, high surface area, and low cost. However, they typically need a high work temperature during sensing process. Here, p-type sensing layer is reported, consisting of pore-rich dumbbell-like Co3O4 particles (DP-Co3O4) with intrinsic high catalytic activity. The gas sensor (GS) based DP-Co3O4 catalyst exhibits ultrahigh NH3 sensing activity along with excellent stability over other structure based NH3 GSs in room temperature work environment. In addition, the unique structure of DP-Co3O4 with pore-rich and high catalytic activity endows fast gas diffusion rate and high sensitivity at room temperature. Taken together, the findings in this work highlight the merit of integrating highly active materials in p-type materials, offering a framework to develop high-sensitivity room temperature sensing platforms.

Bioengineering a Human Plasma-Based Epidermal Substitute With Efficient Grafting Capacity and High Content in Clonogenic Cells

PubMed Central

Alexaline, Maia M.; Trouillas, Marina; Nivet, Muriel; Bourreau, Emilie; Leclerc, Thomas; Duhamel, Patrick; Martin, Michele T.; Doucet, Christelle; Fortunel, Nicolas O.

2015-01-01

Cultured epithelial autografts (CEAs) produced from a small, healthy skin biopsy represent a lifesaving surgical technique in cases of full-thickness skin burn covering >50% of total body surface area. CEAs also present numerous drawbacks, among them the use of animal proteins and cells, the high fragility of keratinocyte sheets, and the immaturity of the dermal-epidermal junction, leading to heavy cosmetic and functional sequelae. To overcome these weaknesses, we developed a human plasma-based epidermal substitute (hPBES) for epidermal coverage in cases of massive burn, as an alternative to traditional CEA, and set up critical quality controls for preclinical and clinical studies. In this study, phenotypical analyses in conjunction with functional assays (clonal analysis, long-term culture, or in vivo graft) showed that our new substitute fulfills the biological requirements for epidermal regeneration. hPBES keratinocytes showed high potential for cell proliferation and subsequent differentiation similar to healthy skin compared with a well-known reference material, as ascertained by a combination of quality controls. This work highlights the importance of integrating relevant multiparameter quality controls into the bioengineering of new skin substitutes before they reach clinical development. Significance This work involves the development of a new bioengineered epidermal substitute with pertinent functional quality controls. The novelty of this work is based on this quality approach. PMID:25848122

Bioengineering a human plasma-based epidermal substitute with efficient grafting capacity and high content in clonogenic cells.

PubMed

Alexaline, Maia M; Trouillas, Marina; Nivet, Muriel; Bourreau, Emilie; Leclerc, Thomas; Duhamel, Patrick; Martin, Michele T; Doucet, Christelle; Fortunel, Nicolas O; Lataillade, Jean-Jacques

2015-06-01

Cultured epithelial autografts (CEAs) produced from a small, healthy skin biopsy represent a lifesaving surgical technique in cases of full-thickness skin burn covering >50% of total body surface area. CEAs also present numerous drawbacks, among them the use of animal proteins and cells, the high fragility of keratinocyte sheets, and the immaturity of the dermal-epidermal junction, leading to heavy cosmetic and functional sequelae. To overcome these weaknesses, we developed a human plasma-based epidermal substitute (hPBES) for epidermal coverage in cases of massive burn, as an alternative to traditional CEA, and set up critical quality controls for preclinical and clinical studies. In this study, phenotypical analyses in conjunction with functional assays (clonal analysis, long-term culture, or in vivo graft) showed that our new substitute fulfills the biological requirements for epidermal regeneration. hPBES keratinocytes showed high potential for cell proliferation and subsequent differentiation similar to healthy skin compared with a well-known reference material, as ascertained by a combination of quality controls. This work highlights the importance of integrating relevant multiparameter quality controls into the bioengineering of new skin substitutes before they reach clinical development. This work involves the development of a new bioengineered epidermal substitute with pertinent functional quality controls. The novelty of this work is based on this quality approach. ©AlphaMed Press.

Shift Work and Sleep: Medical Implications and Management

PubMed Central

Jehan, Shazia; Zizi, Ferdinand; Pandi-Perumal, Seithikurippu R; Myers, Alyson K; Auguste, Evan; Jean-Louis, Girardin; McFarlane, Samy I

2018-01-01

The primary occupation of a worker can play an important role in achieving good sleep, as well as good physical and mental health. Shift Work Sleep Disorder (SWSD) is a condition that results from working atypical shifts (i.e. other than the typical 9 am to 5 pm schedule). Individuals who manifest SWSD usually complaint of trouble sleeping, excessive sleepiness and fatigue which interfere with overall functioning. Misalignment of circadian timing system results in undesirable health consequences. Among shift workers, good sleep is essential for efficient functioning. Disturbed sleep is associated with anxiety, depression, poor physical and mental health and eventually, leads to impaired quality of life. The economic burden of undiagnosed, under-and untreated shift work is high. The healthcare workers and policymakers can play a pivotal role in dealing with this issue by educating the public and providing them with adequate privileges to perform their work. PMID:29517053

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

Highly selective covalent organic functionalization of epitaxial graphene

NASA Astrophysics Data System (ADS)

Bueno, Rebeca A.; Martínez, José I.; Luccas, Roberto F.; Del Árbol, Nerea Ruiz; Munuera, Carmen; Palacio, Irene; Palomares, Francisco J.; Lauwaet, Koen; Thakur, Sangeeta; Baranowski, Jacek M.; Strupinski, Wlodek; López, María F.; Mompean, Federico; García-Hernández, Mar; Martín-Gago, José A.

2017-05-01

Graphene functionalization with organics is expected to be an important step for the development of graphene-based materials with tailored electronic properties. However, its high chemical inertness makes difficult a controlled and selective covalent functionalization, and most of the works performed up to the date report electrostatic molecular adsorption or unruly functionalization. We show hereafter a mechanism for promoting highly specific covalent bonding of any amino-terminated molecule and a description of the operating processes. We show, by different experimental techniques and theoretical methods, that the excess of charge at carbon dangling-bonds formed on single-atomic vacancies at the graphene surface induces enhanced reactivity towards a selective oxidation of the amino group and subsequent integration of the nitrogen within the graphene network. Remarkably, functionalized surfaces retain the electronic properties of pristine graphene. This study opens the door for development of graphene-based interfaces, as nano-bio-hybrid composites, fabrication of dielectrics, plasmonics or spintronics.

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

Daily job demands and employee work engagement: The role of daily transformational leadership behavior.

PubMed

Breevaart, Kimberley; Bakker, Arnold B

2018-07-01

Using job demands-resources (JD-R) theory, the present study integrates the challenge stressor-hindrance stressor framework and leadership theory to investigate the relationship between daily transformational leadership behavior and employee work engagement. We hypothesized that daily transformational leadership behavior (a) sustains employee work engagement on days characterized by high challenge job demands, and (b) protects work engagement on days characterized by high hindrance job demands. Teachers filled out a short online questionnaire at the end of each workday during a 2-week period (N = 271 × 5.68 days = 1539). Results of latent moderated structural equation modeling showed that teachers' daily challenge demands (workload and cognitive demands) had a positive relationship with work engagement on the days transformational leadership was high (vs. low). In addition, teachers' daily hindrance demands (role-conflict, but not family to work conflict) had a negative relationship with work engagement on the days transformational leadership was low (vs. high). These findings show that the function of transformational leadership behavior changes from day to day, and depends on the type of job demand. We discuss the practical and theoretical implications of these findings. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

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.

A tensorial approach to access cognitive workload related to mental arithmetic from EEG functional connectivity estimates.

PubMed

Dimitriadis, S I; Sun, Yu; Kwok, K; Laskaris, N A; Bezerianos, A

2013-01-01

The association of functional connectivity patterns with particular cognitive tasks has long been a topic of interest in neuroscience, e.g., studies of functional connectivity have demonstrated its potential use for decoding various brain states. However, the high-dimensionality of the pairwise functional connectivity limits its usefulness in some real-time applications. In the present study, the methodology of tensor subspace analysis (TSA) is used to reduce the initial high-dimensionality of the pairwise coupling in the original functional connectivity network to a space of condensed descriptive power, which would significantly decrease the computational cost and facilitate the differentiation of brain states. We assess the feasibility of the proposed method on EEG recordings when the subject was performing mental arithmetic task which differ only in the difficulty level (easy: 1-digit addition v.s. 3-digit additions). Two different cortical connective networks were detected, and by comparing the functional connectivity networks in different work states, it was found that the task-difficulty is best reflected in the connectivity structure of sub-graphs extending over parietooccipital sites. Incorporating this data-driven information within original TSA methodology, we succeeded in predicting the difficulty level from connectivity patterns in an efficient way that can be implemented so as to work in real-time.

Can reactivity to stress and family environment explain memory and executive function performance in early and middle childhood?

PubMed

Piccolo, Luciane da Rosa; Salles, Jerusa Fumagalli de; Falceto, Olga Garcia; Fernandes, Carmen Luiza; Grassi-Oliveira, Rodrigo

2016-01-01

According to the literature, children's overall reactivity to stress is associated with their socioeconomic status and family environment. In turn, it has been shown that reactivity to stress is associated with cognitive performance. However, few studies have systematically tested these three constructs together. To investigate the relationship between family environment, salivary cortisol measurements and children's memory and executive function performance. Salivary cortisol levels of 70 children aged 9 or 10 years were measured before and after performing tasks designed to assess memory and executive functions. Questionnaires on socioeconomic issues, family environment and maternal psychopathologies were administered to participants' families during the children's early childhood and again when they reached school age. Data were analyzed by calculating correlations between variables and conducting hierarchical regression. High cortisol levels were associated with poorer working memory and worse performance in tasks involving executive functions, and were also associated with high scores for maternal psychopathology (during early childhood and school age) and family dysfunction. Family environment variables and changes in cortisol levels explain around 20% of the variance in performance of cognitive tasks. Family functioning and maternal psychopathology in early and middle childhood and children's stress levels were associated with children's working memory and executive functioning.

Thermoelectricity in fullerene-metal heterojunctions.

PubMed

Yee, Shannon K; Malen, Jonathan A; Majumdar, Arun; Segalman, Rachel A

2011-10-12

Thermoelectricty in heterojunctions, where a single-molecule is trapped between metal electrodes, has been used to understand transport properties at organic-inorganic interfaces. (1) The transport in these systems is highly dependent on the energy level alignment between the molecular orbitals and the Fermi level (or work function) of the metal contacts. To date, the majority of single-molecule measurements have focused on simple small molecules where transport is dominated through the highest occupied molecular orbital. (2, 3) In these systems, energy level alignment is limited by the absence of electrode materials with low Fermi levels (i.e., large work functions). Alternatively, more controllable alignment between molecular orbitals and the Fermi level can be achieved with molecules whose transport is dominated by the lowest unoccupied molecular orbital (LUMO) because of readily available metals with lower work functions. Herein, we report molecular junction thermoelectric measurements of fullerene molecules (i.e., C(60), PCBM, and C(70)) trapped between metallic electrodes (i.e., Pt, Au, Ag). Fullerene junctions demonstrate the first strongly n-type molecular thermopower corresponding to transport through the LUMO, and the highest measured magnitude of molecular thermopower to date. While the electronic conductance of fullerenes is highly variable, due to fullerene's variable bonding geometries with the electrodes, the thermopower shows predictable trends based on the alignment of the LUMO with the work function of the electrodes. Both the magnitude and trend of the thermopower suggest that heterostructuring organic and inorganic materials at the nanoscale can further enhance thermoelectric performance, therein providing a new pathway for designing thermoelectric materials.

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

Structural brain and neuropsychometric changes associated with pediatric bipolar disorder with psychosis.

PubMed

James, Anthony; Hough, Morgan; James, Susan; Burge, Linda; Winmill, Louise; Nijhawan, Sunita; Matthews, Paul M; Zarei, Mojtaba

2011-02-01

To identify neuropsychological and structural brain changes using a combination of high-resolution structural and diffusion tensor imaging in pediatric bipolar disorder (PBD) with psychosis (presence of delusions and or hallucinations). We recruited 15 patients and 20 euthymic age- and gender-matched healthy controls. All subjects underwent high-resolution structural and diffusion tensor imaging. Voxel-based morphometry (VBM), tract-based spatial statistics (TBSS), and probabilistic tractography were used to analyse magnetic resonance imaging data. The PBD subjects had normal overall intelligence with specific impairments in working memory, executive function, language function, and verbal memory. Reduced gray matter (GM) density was found in the left orbitofrontal cortex, left pars triangularis, right premotor cortex, occipital cortex, right occipital fusiform gyrus, and right crus of the cerebellum. TBSS analysis showed reduced fractional anisotropy (FA) in the anterior corpus callosum. Probabilistic tractography from this cluster showed that this region of the corpus callosum is connected with the prefrontal cortices, including those regions whose density is decreased in PBD. In addition, FA change was correlated with verbal memory and working memory, while more widespread reductions in GM density correlated with working memory, executive function, language function, and verbal memory. The findings suggest widespread cortical changes as well as specific involvement of interhemispheric prefrontal tracts in PBD, which may reflect delayed myelination in these tracts. © 2011 John Wiley and Sons A/S.

Evolution of Metastable Defects and Its Effect on the Electronic Properties of MoS 2 Films

DOE PAGES

Precner, Marian; Polakovic, T.; Qiao, Qiao; ...

2018-04-30

Here, we report on structural and electronic properties of defects in chemical vapor-deposited monolayer and few-layer MoS 2 films. Scanning tunneling microscopy, Kelvin probe force microscopy, and transmission electron microscopy were used to obtain high resolution images and quantitative measurements of the local density of states, work function and nature of defects in MoS 2 films. We track the evolution of defects that are formed under heating and electron beam irradiation. We observe formation of metastable domains with different work function values after annealing the material in ultra-high vacuum to moderate temperatures. We attribute these metastable values of the workmore » function to evolution of crystal defects forming during the annealing. The experiments show that sulfur vacancies formed after exposure to elevated temperatures diffuse, coalesce, and migrate bringing the system from a metastable to equilibrium ground state. The process could be thermally or e-beam activated with estimated energy barrier for sulfur vacancy migration of 0.6 eV in single unit cell MoS 2. Even at equilibrium conditions, the work function and local density of states values are strongly affected near grain boundaries and edges. The results provide initial estimates of the thermal budgets available for reliable fabrication of MoS 2-based integrated electronics and indicate the importance of defect control and layer passivation.« less

Evolution of Metastable Defects and Its Effect on the Electronic Properties of MoS 2 Films

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

Precner, Marian; Polakovic, T.; Qiao, Qiao

Here, we report on structural and electronic properties of defects in chemical vapor-deposited monolayer and few-layer MoS 2 films. Scanning tunneling microscopy, Kelvin probe force microscopy, and transmission electron microscopy were used to obtain high resolution images and quantitative measurements of the local density of states, work function and nature of defects in MoS 2 films. We track the evolution of defects that are formed under heating and electron beam irradiation. We observe formation of metastable domains with different work function values after annealing the material in ultra-high vacuum to moderate temperatures. We attribute these metastable values of the workmore » function to evolution of crystal defects forming during the annealing. The experiments show that sulfur vacancies formed after exposure to elevated temperatures diffuse, coalesce, and migrate bringing the system from a metastable to equilibrium ground state. The process could be thermally or e-beam activated with estimated energy barrier for sulfur vacancy migration of 0.6 eV in single unit cell MoS 2. Even at equilibrium conditions, the work function and local density of states values are strongly affected near grain boundaries and edges. The results provide initial estimates of the thermal budgets available for reliable fabrication of MoS 2-based integrated electronics and indicate the importance of defect control and layer passivation.« less

An Integrated Study on a Novel High Temperature High Entropy Alloy

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

Yang, Shizhong

2016-12-31

This report summarizes our recent works of theoretical modeling, simulation, and experimental validation of the simulation results on the new refractory high entropy alloy (HEA) design and oxide doped refractory HEA research. The simulation of the stability and thermal dynamics simulation on potential thermal stable candidates were performed and related HEA with oxide doped samples were synthesized and characterized. The HEA ab initio density functional theory and molecular dynamics physical property simulation methods and experimental texture validation techniques development, achievements already reached, course work development, students and postdoc training, and future improvement research directions are briefly introduced.

Anxiety and Depression in Academic Performance: An Exploration of the Mediating Factors of Worry and Working Memory

ERIC Educational Resources Information Center

Owens, Matthew; Stevenson, Jim; Hadwin, Julie A.; Norgate, Roger

2012-01-01

Anxiety and depression are linked to lower academic performance. It is proposed that academic performance is reduced in young people with high levels of anxiety or depression as a function of increased test-specific worry that impinges on working memory central executive processes. Participants were typically developing children (12 to…

Peer Effects and Human Capital Accumulation: the Externalities of ADD. NBER Working Paper No. 14354

ERIC Educational Resources Information Center

Aizer, Anna

2008-01-01

Although recent work has shown that peers affect human capital accumulation, the mechanisms are not well understood. Knowing why high achieving peers matter, because of their innate ability, disciplined behavior or some other factor, has important implications for our understanding of the education production function and for how we organize…

Exploring How Pain Leads to Productivity Loss in Primary Care Consulters for Osteoarthritis: A Prospective Cohort Study

PubMed Central

Wilkie, Ross; Hay, Elaine M.; Croft, Peter; Pransky, Glenn

2015-01-01

Objective Osteoarthritis pain has become a leading cause of decreased productivity and work disability in older workers, a major concern in primary care. How osteoarthritis pain leads to decreased productivity at work is unclear; the aim of this study was to elucidate causal mechanisms and thus identify potential opportunities for intervention. Methods Population-based prospective cohort study of primary care consulters with osteoarthritis. Path analysis was used to test proposed mechanisms by examining the association between pain at baseline, and onset of work productivity loss at three years for mediation by physical limitation, depression, poor sleep and poor coping mechanisms. Results High pain intensity was associated with onset of work productivity loss (Adjusted Odds Ratio 2.5; 95%CI 1.3, 4.8). About half of the effect of pain on work productivity was a direct effect, and half was mediated by the impact of pain on physical function. Depression, poor sleep quality and poor coping did not mediate the association between high pain intensity and onset of work productivity loss. Conclusions As pain is a major cause of work productivity loss, results suggest that decreasing pain should be a major focus. However, successfully improving function may have an indirect effect by decreasing the impact of pain on work productivity, especially important as significant pain reduction is often difficult to achieve. Although depression, sleep problems, and coping strategies may be directly related to work productivity loss, addressing these issues may not have much effect on the significant impact of pain on work productivity. PMID:25849594

Exploring how pain leads to productivity loss in primary care consulters for osteoarthritis: a prospective cohort study.

PubMed

Wilkie, Ross; Hay, Elaine M; Croft, Peter; Pransky, Glenn

2015-01-01

Osteoarthritis pain has become a leading cause of decreased productivity and work disability in older workers, a major concern in primary care. How osteoarthritis pain leads to decreased productivity at work is unclear; the aim of this study was to elucidate causal mechanisms and thus identify potential opportunities for intervention. Population-based prospective cohort study of primary care consulters with osteoarthritis. Path analysis was used to test proposed mechanisms by examining the association between pain at baseline, and onset of work productivity loss at three years for mediation by physical limitation, depression, poor sleep and poor coping mechanisms. High pain intensity was associated with onset of work productivity loss (Adjusted Odds Ratio 2.5; 95%CI 1.3, 4.8). About half of the effect of pain on work productivity was a direct effect, and half was mediated by the impact of pain on physical function. Depression, poor sleep quality and poor coping did not mediate the association between high pain intensity and onset of work productivity loss. As pain is a major cause of work productivity loss, results suggest that decreasing pain should be a major focus. However, successfully improving function may have an indirect effect by decreasing the impact of pain on work productivity, especially important as significant pain reduction is often difficult to achieve. Although depression, sleep problems, and coping strategies may be directly related to work productivity loss, addressing these issues may not have much effect on the significant impact of pain on work productivity.

The Role of Fludrocortisone in Cognition and Mood in Patients with Primary Adrenal Insufficiency (Addison's Disease).

PubMed

Schultebraucks, Katharina; Wingenfeld, Katja; Otte, Christian; Quinkler, Marcus

2016-01-01

Primary adrenal insufficiency (AI) requires hormone replacement therapy with fludrocortisone and hydrocortisone stimulating glucocorticoid (GR) and mineralocorticoid receptors (MR). Evidence from animal and human studies shows that MR function is crucial for cognitive function and mood. Regarding patients with AI, very little is known about the role of MR in cognitive function and mood. A repeated-measures within-subject design was used to determine whether cognitive function and mood are related to MR occupation in patients with AI. Intraindividually, patients were examined twice, with 1 week between testing days: once with fludrocortisone (high MR occupation) and once without fludrocortisone (low MR occupation). All patients kept their stable regimen of hydrocortisone. The assessment of cognitive function included executive function, attention, and verbal, visuospatial and working memory. Additionally, mood and blood pressure were measured. Verbal memory improved significantly during high MR occupation (after fludrocortisone intake) compared to low MR occupation [without fludrocortisone, t(29) = -2.1, p = 0.046]. There were trend level differences in the Number-Combination test [t(29) = -1.9, p = 0.074] and in the Stroop interference task [t(29) = -1.9, p = 0.068]. No significant differences in visuospatial and working memory were found. Furthermore, the current mood state was better during high MR occupation compared to low MR occupation [t(29) = -2.4, p = 0.023] as was diastolic blood pressure [F(2, 29) = 3.6, p = 0.07]. Cognitive function and mood in patients with AI depend in part on MR occupation. Because the medium effect size indicates a potential clinical significance, further studies should systematically examine which dosages of fludrocortisone are associated with optimal cognitive function and mood in AI patients. © 2015 S. Karger AG, Basel.

NIH Toolbox Cognition Battery (NIHTB-CB): list sorting test to measure working memory.

PubMed

Tulsky, David S; Carlozzi, Noelle; Chiaravalloti, Nancy D; Beaumont, Jennifer L; Kisala, Pamela A; Mungas, Dan; Conway, Kevin; Gershon, Richard

2014-07-01

The List Sorting Working Memory Test was designed to assess working memory (WM) as part of the NIH Toolbox Cognition Battery. List Sorting is a sequencing task requiring children and adults to sort and sequence stimuli that are presented visually and auditorily. Validation data are presented for 268 participants ages 20 to 85 years. A subset of participants (N=89) was retested 7 to 21 days later. As expected, the List Sorting Test had moderately high correlations with other measures of working memory and executive functioning (convergent validity) but a low correlation with a test of receptive vocabulary (discriminant validity). Furthermore, List Sorting demonstrates expected changes over the age span and has excellent test-retest reliability. Collectively, these results provide initial support for the construct validity of the List Sorting Working Memory Measure as a measure of working memory. However, the relationship between the List Sorting Test and general executive function has yet to be determined.

NIH Toolbox Cognition Battery (NIHTB-CB): The List Sorting Test to Measure Working Memory

PubMed Central

Tulsky, David S.; Carlozzi, Noelle; Chiaravalloti, Nancy D.; Beaumont, Jennifer L.; Kisala, Pamela A.; Mungas, Dan; Conway, Kevin; Gershon, Richard

2015-01-01

The List Sorting Working Memory Test was designed to assess working memory (WM) as part of the NIH Toolbox Cognition Battery. List Sorting is a sequencing task requiring children and adults to sort and sequence stimuli that are presented visually and auditorily. Validation data are presented for 268 participants ages 20 to 85 years. A subset of participants (N=89) was retested 7 to 21 days later. As expected, the List Sorting Test had moderately high correlations with other measures of working memory and executive functioning (convergent validity) but a low correlation with a test of receptive vocabulary (discriminant validity). Furthermore, List Sorting demonstrates expected changes over the age span and has excellent test-retest reliability. Collectively, these results provide initial support the construct validity of the List Sorting Working Memory Measure as a measure of working memory. However, the relation between the List Sorting Test and general executive function has yet to be determined. PMID:24959983

A Novel Ni/WOX/W Resistive Random Access Memory with Excellent Retention and Low Switching Current

NASA Astrophysics Data System (ADS)

Chien, Wei-Chih; Chen, Yi-Chou; Lee, Feng-Ming; Lin, Yu-Yu; Lai, Erh-Kun; Yao, Yeong-Der; Gong, Jeng; Horng, Sheng-Fu; Yeh, Chiao-Wen; Tsai, Shih-Chang; Lee, Ching-Hsiung; Huang, Yu-Kai; Chen, Chun-Fu; Kao, Hsiao-Feng; Shih, Yen-Hao; Hsieh, Kuang-Yeu; Lu, Chih-Yuan

2011-04-01

The behavior of WOX resistive random access memory (ReRAM) is a strong function of the top electrode material, which controls the conduction mechanism and the forming process. When using a top electrode with low work function, the current conduction is limited by space charges. On the other hand, the mechanism becomes thermionic emission for devices with a high work function top electrode. These (thermionic) devices are also found to have higher initial resistance, reduced forming current, and larger resistance window. Based on these insights and considering the compatibility to complementary metal-oxide-semiconductor (CMOS) process, we proposed to use Ni as the top electrode for high performance WOX ReRAM devices. The new Ni/WOX/W device can be switched at a low current density less than 8×105 A/cm2, with RESET/SET resistance ratio greater than 100, and extremely good data retention of more than 300 years at 85 °C.

High efficiency protein separation with organosilane assembled silica coated magnetic nanoparticles

NASA Astrophysics Data System (ADS)

Chang, Jeong Ho; Kang, Ki Ho; Choi, Jinsub; Jeong, Young Keun

2008-10-01

This work describes the development of high efficiency protein separation with functionalized organosilanes on the surface of silica coated magnetic nanoparticles. The magnetic nanoparticles were synthesized with average particle size of 9 nm and silica coated magnetic nanoparticles were obtained by controlling the coating thicknesses on magnetic nanoparticles. The silica coating thickness could be uniformly sized with a diameter of 10-40 nm by a sol-gel approach. The surface modification was performed with four kinds of functionalized organosilanes such as carboxyl, aldehyde, amine, and thiol groups. The protein separation work with organosilane assembled silica coated magnetic nanoparticles was achieved for model proteins such as bovine serum albumin (BSA) and lysozyme (LSZ) at different pH conditions. Among the various functionalities, the thiol group showed good separation efficiency due to the change of electrostatic interactions and protein conformational structure. The adsorption efficiency of BSA and LSZ was up to 74% and 90% corresponding pH 4.65 and pH 11.

Members of the YjgF/YER057c/UK114 family of proteins inhibit phosphoribosylamine synthesis in vitro.

PubMed

Lambrecht, Jennifer A; Browne, Beth Ann; Downs, Diana M

2010-11-05

The YjgF/YER057c/UK114 family of proteins is highly conserved across all three domains of life and currently lacks a consensus biochemical function. Analysis of Salmonella enterica strains lacking yjgF has led to a working model in which YjgF functions to remove potentially toxic secondary products of cellular enzymes. Strains lacking yjgF synthesize the thiamine precursor phosphoribosylamine (PRA) by a TrpD-dependent mechanism that is not present in wild-type strains. Here, PRA synthesis was reconstituted in vitro with anthranilate phosphoribosyltransferase (TrpD), threonine dehydratase (IlvA), threonine, and phosphoribosyl pyrophosphate. TrpD-dependent PRA formation in vitro was inhibited by S. enterica YjgF and the human homolog UK114. Thus, the work herein describes the first biochemical assay for diverse members of the highly conserved YjgF/YER057c/UK114 family of proteins and provides a means to dissect the cellular functions of these proteins.

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.

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.

Polarized pressure dependence of the anisotropic dielectric functions of highly oriented poly(p-phenylene vinylene)

NASA Astrophysics Data System (ADS)

Morandi, V.; Galli, M.; Marabelli, F.; Comoretto, D.

2010-04-01

In this work, we combined an experimental technique and a detailed data analysis to investigate the influence of an applied pressure on the anisotropic dielectric functions of highly oriented poly(p-phenylene vinylene) (PPV). The dielectric constants were derived from polarized reflectance spectra recorded through a diamond anvil cell up to 50 kbar. The presence of the diamond anvils strongly affects measured spectra requiring the development in an optical model able to take all spurious effects into account. A parametric procedure was then applied to derive the complex dielectric constants for both polarizations as a function of pressure. A detailed analysis of their pressure dependence allows addressing the role of intermolecular interactions and electron-phonon coupling in highly oriented PPV.

Electrophysiological Measures of Resting State Functional Connectivity and Their Relationship with Working Memory Capacity in Childhood

ERIC Educational Resources Information Center

Barnes, Jessica J.; Woolrich, Mark W.; Baker, Kate; Colclough, Giles L.; Astle, Duncan E.

2016-01-01

Functional connectivity is the statistical association of neuronal activity time courses across distinct brain regions, supporting specific cognitive processes. This coordination of activity is likely to be highly important for complex aspects of cognition, such as the communication of fluctuating task goals from higher-order control regions to…

Design Development Plans for Altamont Junior High School, Klamath Falls, Oregon.

ERIC Educational Resources Information Center

Lutes and Amundson, Architects and Community Planners, Springfield, OR.

The architects, with the teaching staff, administration, students, and community, worked as a team to make a coordinated statement of the physical, functional, and esthetic proposals for a new school. The space and functional requirements of each teaching area have been documented and analyzed to arrive at a realistic appraisal of need for the…

Violence Prevention and Students with Disabilities: Thinking Functionally and Providing Evidence Based Supports and Accommodations

ERIC Educational Resources Information Center

Rosenberg, Michael S.

2012-01-01

Students with disabilities who engage in high rates of challenging behaviors require educators who employ function-based thinking and have a particular sensitivity to the wide range of factors that influence student behavior. In essence, educators working with special needs students need to know what makes their instruction "special"; they must…

Focusing on Attention: The Effects of Working Memory Capacity and Load on Selective Attention

PubMed Central

Ahmed, Lubna; de Fockert, Jan W.

2012-01-01

Background Working memory (WM) is imperative for effective selective attention. Distractibility is greater under conditions of high (vs. low) concurrent working memory load (WML), and in individuals with low (vs. high) working memory capacity (WMC). In the current experiments, we recorded the flanker task performance of individuals with high and low WMC during low and high WML, to investigate the combined effect of WML and WMC on selective attention. Methodology/Principal Findings In Experiment 1, distractibility from a distractor at a fixed distance from the target was greater when either WML was high or WMC was low, but surprisingly smaller when both WML was high and WMC low. Thus we observed an inverted-U relationship between reductions in WM resources and distractibility. In Experiment 2, we mapped the distribution of spatial attention as a function of WMC and WML, by recording distractibility across several target-to-distractor distances. The pattern of distractor effects across the target-to-distractor distances demonstrated that the distribution of the attentional window becomes dispersed as WM resources are limited. The attentional window was more spread out under high compared to low WML, and for low compared to high WMC individuals, and even more so when the two factors co-occurred (i.e., under high WML in low WMC individuals). The inverted-U pattern of distractibility effects in Experiment 1, replicated in Experiment 2, can thus be explained by differences in the spread of the attentional window as a function of WM resource availability. Conclusions/Significance The current findings show that limitations in WM resources, due to either WML or individual differences in WMC, affect the spatial distribution of attention. The difference in attentional constraining between high and low WMC individuals demonstrated in the current experiments helps characterise the nature of previously established associations between WMC and controlled attention. PMID:22952636

Computational design of nanoparticle drug delivery systems for selective targeting

NASA Astrophysics Data System (ADS)

Duncan, Gregg A.; Bevan, Michael A.

2015-09-01

Ligand-functionalized nanoparticles capable of selectively binding to diseased versus healthy cell populations are attractive for improved efficacy of nanoparticle-based drug and gene therapies. However, nanoparticles functionalized with high affinity targeting ligands may lead to undesired off-target binding to healthy cells. In this work, Monte Carlo simulations were used to quantitatively determine net surface interactions, binding valency, and selectivity between targeted nanoparticles and cell surfaces. Dissociation constant, KD, and target membrane protein density, ρR, are explored over a range representative of healthy and cancerous cell surfaces. Our findings show highly selective binding to diseased cell surfaces can be achieved with multiple, weaker affinity targeting ligands that can be further optimized by varying the targeting ligand density, ρL. Using the approach developed in this work, nanomedicines can be optimally designed for exclusively targeting diseased cells and tissues.Ligand-functionalized nanoparticles capable of selectively binding to diseased versus healthy cell populations are attractive for improved efficacy of nanoparticle-based drug and gene therapies. However, nanoparticles functionalized with high affinity targeting ligands may lead to undesired off-target binding to healthy cells. In this work, Monte Carlo simulations were used to quantitatively determine net surface interactions, binding valency, and selectivity between targeted nanoparticles and cell surfaces. Dissociation constant, KD, and target membrane protein density, ρR, are explored over a range representative of healthy and cancerous cell surfaces. Our findings show highly selective binding to diseased cell surfaces can be achieved with multiple, weaker affinity targeting ligands that can be further optimized by varying the targeting ligand density, ρL. Using the approach developed in this work, nanomedicines can be optimally designed for exclusively targeting diseased cells and tissues. Electronic supplementary information (ESI) available: Movie showing simulation renderings of targeted (ρL = 1820/μm2, KD = 120 μM) nanoparticle selective binding to cancer (ρR = 256/μm2) vs. healthy (ρR = 64/μm2) cell surfaces. Target membrane proteins have linear color scale depending on binding energy ranging from white when unbound (URL = 0) to red when tightly bound (URL = UM). See DOI: 10.1039/c5nr03691g

Sensing Properties of GO and Amine-Silica Nanoparticles Functionalized QCM Sensors for Detection of Formaldehyde

NASA Astrophysics Data System (ADS)

Wang, Zhenqiang; Yang, Mingqing; He, Junhui

2014-12-01

In the current work, graphene oxides (GO) and Amine-Functionalized Silica Nanoparticles (NH2-SNs) were used as sensing layer on quart crystal microbalance (QCM) for detection of HCHO gas. The GO and NH2-SNs functionalized QCM resonators all had a significant response to HCHO gas. The sensitivity of GO functionalized QCM resonator is 0.04 Hz/(μgṡppm), which is four times as high as that of NH2-SNs functionalized QCM resonator (0.01 Hz/(μgṡppm)). The GO functionalized QCM resonators would be of benefit in area of environmental applications.

Project Summary Report

NASA Technical Reports Server (NTRS)

Upchurch, Christopher

2011-01-01

The project, being the development of resource management applications, consisted entirely of my own effort. From deliverable requirements provided by my mentor, and some functional requirement additions generated through design reviews, It was my responsibility to implement the requested features as well as possible, given the resources available. For the most part development work consisted of database programming and functional testing using real resource data. Additional projects I worked on included some firing room console training, configuring the new NE-A microcontroller development lab network, mentoring high school CubeSat students, and managing the NE interns' component of the mentor appreciation ceremony.

Note: Work function change measurement via improved Anderson method

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

Sabik, A., E-mail: sabik@ifd.uni.wroc.pl; Gołek, F.; Antczak, G.

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

Assessing the Driver’s Current Level of Working Memory Load with High Density Functional Near-infrared Spectroscopy: A Realistic Driving Simulator Study

PubMed Central

Unni, Anirudh; Ihme, Klas; Jipp, Meike; Rieger, Jochem W.

2017-01-01

Cognitive overload or underload results in a decrease in human performance which may result in fatal incidents while driving. We envision that driver assistive systems which adapt their functionality to the driver’s cognitive state could be a promising approach to reduce road accidents due to human errors. This research attempts to predict variations of cognitive working memory load levels in a natural driving scenario with multiple parallel tasks and to reveal predictive brain areas. We used a modified version of the n-back task to induce five different working memory load levels (from 0-back up to 4-back) forcing the participants to continuously update, memorize, and recall the previous ‘n’ speed sequences and adjust their speed accordingly while they drove for approximately 60 min on a highway with concurrent traffic in a virtual reality driving simulator. We measured brain activation using multichannel whole head, high density functional near-infrared spectroscopy (fNIRS) and predicted working memory load level from the fNIRS data by combining multivariate lasso regression and cross-validation. This allowed us to predict variations in working memory load in a continuous time-resolved manner with mean Pearson correlations between induced and predicted working memory load over 15 participants of 0.61 [standard error (SE) 0.04] and a maximum of 0.8. Restricting the analysis to prefrontal sensors placed over the forehead reduced the mean correlation to 0.38 (SE 0.04), indicating additional information gained through whole head coverage. Moreover, working memory load predictions derived from peripheral heart rate parameters achieved much lower correlations (mean 0.21, SE 0.1). Importantly, whole head fNIRS sampling revealed increasing brain activation in bilateral inferior frontal and bilateral temporo-occipital brain areas with increasing working memory load levels suggesting that these areas are specifically involved in workload-related processing. PMID:28424602

Assessing the Driver's Current Level of Working Memory Load with High Density Functional Near-infrared Spectroscopy: A Realistic Driving Simulator Study.

PubMed

Unni, Anirudh; Ihme, Klas; Jipp, Meike; Rieger, Jochem W

2017-01-01

Cognitive overload or underload results in a decrease in human performance which may result in fatal incidents while driving. We envision that driver assistive systems which adapt their functionality to the driver's cognitive state could be a promising approach to reduce road accidents due to human errors. This research attempts to predict variations of cognitive working memory load levels in a natural driving scenario with multiple parallel tasks and to reveal predictive brain areas. We used a modified version of the n-back task to induce five different working memory load levels (from 0-back up to 4-back) forcing the participants to continuously update, memorize, and recall the previous 'n' speed sequences and adjust their speed accordingly while they drove for approximately 60 min on a highway with concurrent traffic in a virtual reality driving simulator. We measured brain activation using multichannel whole head, high density functional near-infrared spectroscopy (fNIRS) and predicted working memory load level from the fNIRS data by combining multivariate lasso regression and cross-validation. This allowed us to predict variations in working memory load in a continuous time-resolved manner with mean Pearson correlations between induced and predicted working memory load over 15 participants of 0.61 [standard error (SE) 0.04] and a maximum of 0.8. Restricting the analysis to prefrontal sensors placed over the forehead reduced the mean correlation to 0.38 (SE 0.04), indicating additional information gained through whole head coverage. Moreover, working memory load predictions derived from peripheral heart rate parameters achieved much lower correlations (mean 0.21, SE 0.1). Importantly, whole head fNIRS sampling revealed increasing brain activation in bilateral inferior frontal and bilateral temporo-occipital brain areas with increasing working memory load levels suggesting that these areas are specifically involved in workload-related processing.

Executive function in children with high and low attentional skills: correspondences between behavioural and cognitive profiles.

PubMed

Scope, Alison; Empson, Janet; McHale, Sue

2010-06-01

Cognitive performance was compared between two groups of typically developing children, who had been observed and rated as differing significantly in their attentional skills at school. The participants were 24 8- and 9-year-old children scoring poorly relative to peers, on a classroom observation scale and teacher rating scale for attention, hyperactivity, and impulsivity [low-attentional skills (LAS) group] and 24 sex- and age-matched children scoring at a high level compared to peers [high-attentional skills (HAS) group]. The two groups were compared on a series of cognitive tasks to assess executive function (EF). The LAS group performed within the typical range yetat a significantly lower level than the HAS group on the majority of the EF tasks administered, namely working memory and inhibition measures, even though there were no significant differences between the groups on a measure of intellectual ability. Working memory measures followed by measures of inhibition emerged as the best predictors of group membership. These findings provide empirical evidence that there are individual differences in attentional skills. Specifically, that there is a relationship between behavioural inattention, hyperactivity, and impulsivity and cognitive performance on working memory and inhibitory control tasks.

Measuring Work Functioning: Validity of a Weighted Composite Work Functioning Approach.

PubMed

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

2015-09-01

To examine the construct validity of a weighted composite work functioning measurement approach. Workers (health-impaired/healthy) (n = 117) completed a composite measure survey that recorded four central work functioning aspects with existing scales: capacity to work, quality of work performance, quantity of work, and recovery from work. Previous derived weights reflecting the relative importance of these aspects of work functioning were used to calculate the composite weighted work functioning score of the workers. Work role functioning, productivity, and quality of life were used for validation. Correlations were calculated and norms applied to examine convergent and divergent construct validity. A t test was conducted and a norm applied to examine discriminative construct validity. Overall the weighted composite work functioning measure demonstrated construct validity. As predicted, the weighted composite score correlated (p < .001) strongly (r > .60) with work role functioning and productivity (convergent construct validity), and moderately (.30 < r < .60) with physical quality of life and less strongly than work role functioning and productivity with mental quality of life (divergent validity). Further, the weighted composite measure detected that health-impaired workers show with a large effect size (Cohen's d > .80) significantly worse work functioning than healthy workers (discriminative validity). The weighted composite work functioning measurement approach takes into account the relative importance of the different work functioning aspects and demonstrated good convergent, fair divergent, and good discriminative construct validity.

Multilevel quantum Otto heat engines with identical particles

NASA Astrophysics Data System (ADS)

Huang, X. L.; Guo, D. Y.; Wu, S. L.; Yi, X. X.

2018-02-01

A quantum Otto heat engine is studied with multilevel identical particles trapped in one-dimensional box potential as working substance. The symmetrical wave function for Bosons and the anti-symmetrical wave function for Fermions are considered. In two-particle case, we focus on the ratios of W^i (i=B,F) to W_s, where W^B and W^F are the work done by two Bosons and Fermions, respectively, and W_s is the work output of a single particle under the same conditions. Due to the symmetrical of the wave functions, the ratios are not equal to 2. Three different regimes, low-temperature regime, high-temperature regime, and intermediate-temperature regime, are analyzed, and the effects of energy level number and the differences between the two baths are calculated. In the multiparticle case, we calculate the ratios of W^i_M/M to W_s, where W^i_M/M can be seen as the average work done by a single particle in multiparticle heat engine. For other working substances whose energy spectrum has the form of E_n˜ n^2, the results are similar. For the case E_n˜ n, two different conclusions are obtained.

Age-dependent and -independent changes in attention-deficit/hyperactivity disorder (ADHD) during spatial working memory performance.

PubMed

Bollmann, Steffen; Ghisleni, Carmen; Poil, Simon-Shlomo; Martin, Ernst; Ball, Juliane; Eich-Höchli, Dominique; Klaver, Peter; O'Gorman, Ruth L; Michels, Lars; Brandeis, Daniel

2017-06-01

Attention-deficit/hyperactivity disorder (ADHD) has been associated with spatial working memory as well as frontostriatal core deficits. However, it is still unclear how the link between these frontostriatal deficits and working memory function in ADHD differs in children and adults. This study examined spatial working memory in adults and children with ADHD, focussing on identifying regions demonstrating age-invariant or age-dependent abnormalities. We used functional magnetic resonance imaging to examine a group of 26 children and 35 adults to study load manipulated spatial working memory in patients and controls. In comparison to healthy controls, patients demonstrated reduced positive parietal and frontostriatal load effects, i.e., less increase in brain activity from low to high load, despite similar task performance. In addition, younger patients showed negative load effects, i.e., a decrease in brain activity from low to high load, in medial prefrontal regions. Load effect differences between ADHD and controls that differed between age groups were found predominantly in prefrontal regions. Age-invariant load effect differences occurred predominantly in frontostriatal regions. The age-dependent deviations support the role of prefrontal maturation and compensation in ADHD, while the age-invariant alterations observed in frontostriatal regions provide further evidence that these regions reflect a core pathophysiology in ADHD.

Inverted amorphous silicon solar cell utilizing cermet layers

DOEpatents

Hanak, Joseph J.

1979-01-01

An amorphous silicon solar cell incorporating a transparent high work function metal cermet incident to solar radiation and a thick film cermet contacting the amorphous silicon opposite to said incident surface.

Diagnosing and improving functioning in interdisciplinary health care teams.

PubMed

Blackmore, Gail; Persaud, D David

2012-01-01

Interdisciplinary teams play a key role in the delivery of health care. Team functioning can positively or negatively impact the effective and efficient delivery of health care services as well as the personal well-being of group members. Additionally, teams must be able and willing to work together to achieve team goals within a climate that reflects commitment to team goals, accountability, respect, and trust. Not surprisingly, dysfunctional team functioning can limit the success of interdisciplinary health care teams. The first step in improving dysfunctional team function is to conduct an analysis based on criteria necessary for team success, and this article provides meaningful criteria for doing such an analysis. These are the following: a common team goal, the ability and willingness to work together to achieve team goals, decision making, communication, and team member relationships. High-functioning interdisciplinary teams must exhibit features of good team function in all key domains. If a team functions well in some domains and needs to improve in others, targeted strategies are described that can be used to improve team functioning.

2D Superparamagnetic Tantalum Carbide Composite MXenes for Efficient Breast-Cancer Theranostics

PubMed Central

Liu, Zhuang; Lin, Han; Zhao, Menglong; Dai, Chen; Zhang, Shengjian; Peng, Weijun; Chen, Yu

2018-01-01

Background: The emergence of two-dimensional MXenes has spurred their versatile applications in broad fields, but the exploring of novel MXene-based family members and their potential applications in theranostic nanomedicine (concurrent diagnostic imaging and therapy) have been rarely explored. In this work, we report the construction of a novel superparamagnetic MXene-based theranostic nanoplatform for efficient breast-cancer theranostics, which was based on intriguing tantalum carbide (Ta4C3) MXene and its further rational surface-superparamagnetic iron-oxide functionalization (Ta4C3-IONP-SPs composite MXenes) for efficient breast-cancer theranostic. Methods: The fabrication of ultrathin Ta4C3 nanosheets was based on an exfoliation strategy and superparamagnetic iron oxide nanoparticles were in-situ grown onto the surface of Ta4C3 MXene according to the redox reaction of MXene. Ta4C3-IONP MXenes were modified with soybean phospholipid (SP) to guarantee high stability in physiological conditions. The photothermal therapy, contrast-enhanced CT, T2-weighted magnetic resonance imaging and the high biocompatibility of these composite nanosheets have also been evaluated in vitro at cellular level and in vivo on mice breast tumor allograft tumor model. Results: The Ta component of Ta4C3-IONP-SPs exhibits high performance for contrast-enhanced CT imaging because of its high atomic number and high X-ray attenuation coefficient, and the integrated superparamagnetic IONPs act as excellent contrast agents for T2-weighted magnetic resonance imaging. Especially, these Ta4C3-IONP-SPs composite nanosheets with high photothermal-conversion efficiency (η: 32.5%) has achieved complete tumor eradication without reoccurrence, verifying their highly efficient breast-tumor photo-ablation performance. Conclusion: This work not only significantly broadens the biomedical applications of MXene-based nanoplatforms (Ta4C3 MXene) by exploring their novel family members and further functionalization strategies (magnetic functionalization in this work), but also provides a novel and efficient theranostic nanoplatform for efficient breast-cancer theranostics. PMID:29556347

Real-time state estimation in a flight simulator using fNIRS.

PubMed

Gateau, Thibault; Durantin, Gautier; Lancelot, Francois; Scannella, Sebastien; Dehais, Frederic

2015-01-01

Working memory is a key executive function for flying an aircraft. This function is particularly critical when pilots have to recall series of air traffic control instructions. However, working memory limitations may jeopardize flight safety. Since the functional near-infrared spectroscopy (fNIRS) method seems promising for assessing working memory load, our objective is to implement an on-line fNIRS-based inference system that integrates two complementary estimators. The first estimator is a real-time state estimation MACD-based algorithm dedicated to identifying the pilot's instantaneous mental state (not-on-task vs. on-task). It does not require a calibration process to perform its estimation. The second estimator is an on-line SVM-based classifier that is able to discriminate task difficulty (low working memory load vs. high working memory load). These two estimators were tested with 19 pilots who were placed in a realistic flight simulator and were asked to recall air traffic control instructions. We found that the estimated pilot's mental state matched significantly better than chance with the pilot's real state (62% global accuracy, 58% specificity, and 72% sensitivity). The second estimator, dedicated to assessing single trial working memory loads, led to 80% classification accuracy, 72% specificity, and 89% sensitivity. These two estimators establish reusable blocks for further fNIRS-based passive brain computer interface development.

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.

Exposure to maltreatment and urban violence in children working on the streets in São Paulo, Brazil: factors associated with street work.

PubMed

Mello, Andrea F; Maciel, Mariana R; Fossaluza, Victor; Paula, Cristiane S de; Grassi-Oliveira, Rodrigo; Cavalcante-Nóbrega, Luciana P; Cividanes, Giuliana C; Soussumi, Yusaku; Soussumi, Sonia P; Perissinotti, Dirce N M; Bordin, Isabel A; Mello, Marcelo F; Mari, Jair J

2014-09-01

To quantitatively study the exposure to childhood maltreatment and urban violence in children from families with at least one child working on the streets and to investigate the relationship between these factors and street work. Families who participated in a nongovernmental organization (NGO) program to eliminate child labor were included. Data concerning sociodemographic characteristics, punishment methods used in the family environment against the children, five types of abuse and neglect perpetrated by the caregivers, urban violence exposure and family functioning were collected. The sample included 126 children who were working on the streets and 65 siblings who were not working on the streets. Caregivers reported high levels of severe physical punishment. The children reported high levels of abuse and neglect, and high levels of urban violence exposure. The families showed a predominance of dysfunctional and unsatisfactory relationships. A multiple logistic regression model showed that age older than 12 years and severe physical punishment at home were associated with street work. Interventions to decrease the risk of child street work should be family-focused and should aim to reduce violence in the family environment.

[Use of high frequency cinematography in diagnosis of globus sensation].

PubMed

Alberty, J; Oelerich, M

1996-09-01

Globus pharyngis is a frequent symptom in patients who consult an otolaryngologist. In many cases, routine diagnostic work-up including history, clinical examination, and barium swallow fail to revealing the underlying pathogenesis. In a retrospective study, we present 51 selected patients suffering from globus pharyngis of unknown origin who were investigated by high-speed cineradiography in a standardized manner. Twenty-four of the patients enrolled in the study (47.1%) showed functional and/or structural swallowing disorders. In 13 cases (25.5%) dyskinesias of the superior esophagus sphincter muscle were found. Five of these patients (9.8%) also had an inconstant hypopharyngeal diverticulum. Six cases (11.8%) showed laryngeal penetration or tracheal aspiration. In four cases (7.8%) functional disorders of pharyngeal, and in three cases (5.9%) functional disorders of oral bolus transport were found. Furthermore one hypopharyngeal web (1.9%) and two benign tumors (3.9%) were detected. In many cases, varying combinations of these findings occurred. Using high-speed cineradiography for evaluation of globus pharyngis results in an increased incidence of pathologic findings, and thus is an important method for interdisciplinary diagnostic work up of patients suffering from this symptom.

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.

Harvesting Vibrational Energy Using Material Work Functions

PubMed Central

Varpula, Aapo; Laakso, Sampo J.; Havia, Tahvo; Kyynäräinen, Jukka; Prunnila, Mika

2014-01-01

Vibration energy harvesters scavenge energy from mechanical vibrations to energise low power electronic devices. In this work, we report on vibration energy harvesting scheme based on the charging phenomenon occurring naturally between two bodies with different work functions. Such work function energy harvester (WFEH) is similar to electrostatic energy harvester with the fundamental distinction that neither external power supplies nor electrets are needed. A theoretical model and description of different operation modes of WFEHs are presented. The WFEH concept is tested with macroscopic experiments, which agree well with the model. The feasibility of miniaturizing WFEHs is shown by simulating a realistic MEMS device. The WFEH can be operated as a charge pump that pushes charge and energy into an energy storage element. We show that such an operation mode is highly desirable for applications and that it can be realised with either a charge shuttle or with switches. The WFEH is shown to give equal or better output power in comparison to traditional electrostatic harvesters. Our findings indicate that WFEH has great potential in energy harvesting applications. PMID:25348004

Why employees with higher challenging appraisals style are more affectively engaged at work? The role of challenging stressors: a moderated mediation model.

PubMed

Lin, Shin-Huei; Wu, Chia-Huei; Chen, Mei-Yen; Chen, Lung Hung

2014-10-01

Challenging stressors have been positively linked to various work outcomes. However, the role of individual differences in stress appraisal in shaping the function of challenging stressors and work outcomes has been rarely discussed. Drawing on the individual differences perspective, the authors propose that employees higher in challenge appraisal are more likely to have challenging stressors and are more responsive to such stressors to have a higher positive affect at work. Results obtained from 117 employees supported the hypotheses. The results indicated that challenge appraisal is positively related to challenging stressors. In addition, challenging stressors has a positive association with positive affect at work when challenge appraisal is high but has a null association when challenge appraisal is low. The findings suggest that challenging stressors does not necessarily bring positive work outcomes as suggested in past studies and highlight the importance of considering dispositional tendency in stress appraisal when looking into the function of challenging stressors and work outcomes. © 2014 International Union of Psychological Science.

Assessing Verbal Functioning in South African School Beginners from Diverse Socioeconomic Backgrounds: A Comparison between Verbal Working Memory and Vocabulary Measures

ERIC Educational Resources Information Center

Cockcroft, Kate; Bloch, Lauren; Moolla, Azra

2016-01-01

This study investigated whether measures of verbal working memory are less sensitive to children's socioeconomic background than traditional vocabulary measures. Participants were 120 school beginners, divided into high and low socioeconomic groups. The groups contained equal numbers of English first-language and second-language speakers. All were…

A Functional High-Throughput Assay of Myelination in Vitro

DTIC Science & Technology

2013-07-01

feasibility of developing microengineered human neural tissues that can be assessed non-invasively. A population of neurons has been derived from human...physiological responses in microengineered tissue constructs has been demonstrated. This works represents a unique combination of enabling...and recording from microengineered tissues. All progress and results discussed in this report are in regard to the revised Statement of Work

The Influence of Working Memory on Reading and Creative Writing Processes in a Second Language.

ERIC Educational Resources Information Center

Abu-Rabia, Salim

2003-01-01

Investigates the working memory (WM) processing and storage functions; whether WM in writing follows the same process as in reading; and the influence of WM on creative writing. Focuses on high school students (n=47). Finds relationships between WM measures and reading and writing in English as a Second Language. Includes references. (CMK)

The effect of motivation on working memory: an fMRI and SEM study.

PubMed

Szatkowska, Iwona; Bogorodzki, Piotr; Wolak, Tomasz; Marchewka, Artur; Szeszkowski, Wojciech

2008-09-01

This study investigated the effective connectivity between prefrontal regions of human brain supporting motivational influence on working memory. Functional magnetic resonance imaging (fMRI) and structural equation modeling (SEM) were used to examine the interaction between the lateral orbitofrontal (OFC), medial OFC, and dorsolateral prefrontal (DLPFC) regions in the left and right hemisphere during performance of the verbal 2-back working memory task under two reinforcement conditions. The "low-motivation" condition was not associated with monetary reinforcement, while the "high-motivation" condition involved the probability of winning a certain amount of money. In the "low-motivation" condition, the OFC regions in both hemispheres positively influenced the left DLPFC activity. In the "high-motivation" condition, the connectivity in the network including the right OFC regions and left DLPFC changed from positive to negative, whereas the positive connectivity in the network composed of the left OFC and left DLPFC became slightly enhanced compared with the "low-motivation" condition. However, only the connection between the right lateral OFC and left DLPFC showed a significant condition-dependent change in the strength of influence conveyed through the pathway. This change appears to be the functional correlate of motivational influence on verbal working memory.

Whole-brain functional connectivity during acquisition of novel grammar: Distinct functional networks depend on language learning abilities.

PubMed

Kepinska, Olga; de Rover, Mischa; Caspers, Johanneke; Schiller, Niels O

2017-03-01

In an effort to advance the understanding of brain function and organisation accompanying second language learning, we investigate the neural substrates of novel grammar learning in a group of healthy adults, consisting of participants with high and average language analytical abilities (LAA). By means of an Independent Components Analysis, a data-driven approach to functional connectivity of the brain, the fMRI data collected during a grammar-learning task were decomposed into maps representing separate cognitive processes. These included the default mode, task-positive, working memory, visual, cerebellar and emotional networks. We further tested for differences within the components, representing individual differences between the High and Average LAA learners. We found high analytical abilities to be coupled with stronger contributions to the task-positive network from areas adjacent to bilateral Broca's region, stronger connectivity within the working memory network and within the emotional network. Average LAA participants displayed stronger engagement within the task-positive network from areas adjacent to the right-hemisphere homologue of Broca's region and typical to lower level processing (visual word recognition), and increased connectivity within the default mode network. The significance of each of the identified networks for the grammar learning process is presented next to a discussion on the established markers of inter-individual learners' differences. We conclude that in terms of functional connectivity, the engagement of brain's networks during grammar acquisition is coupled with one's language learning abilities. Copyright © 2016 Elsevier B.V. All rights reserved.

Inferring probabilistic stellar rotation periods using Gaussian processes

NASA Astrophysics Data System (ADS)

Angus, Ruth; Morton, Timothy; Aigrain, Suzanne; Foreman-Mackey, Daniel; Rajpaul, Vinesh

2018-02-01

Variability in the light curves of spotted, rotating stars is often non-sinusoidal and quasi-periodic - spots move on the stellar surface and have finite lifetimes, causing stellar flux variations to slowly shift in phase. A strictly periodic sinusoid therefore cannot accurately model a rotationally modulated stellar light curve. Physical models of stellar surfaces have many drawbacks preventing effective inference, such as highly degenerate or high-dimensional parameter spaces. In this work, we test an appropriate effective model: a Gaussian Process with a quasi-periodic covariance kernel function. This highly flexible model allows sampling of the posterior probability density function of the periodic parameter, marginalizing over the other kernel hyperparameters using a Markov Chain Monte Carlo approach. To test the effectiveness of this method, we infer rotation periods from 333 simulated stellar light curves, demonstrating that the Gaussian process method produces periods that are more accurate than both a sine-fitting periodogram and an autocorrelation function method. We also demonstrate that it works well on real data, by inferring rotation periods for 275 Kepler stars with previously measured periods. We provide a table of rotation periods for these and many more, altogether 1102 Kepler objects of interest, and their posterior probability density function samples. Because this method delivers posterior probability density functions, it will enable hierarchical studies involving stellar rotation, particularly those involving population modelling, such as inferring stellar ages, obliquities in exoplanet systems, or characterizing star-planet interactions. The code used to implement this method is available online.

High indoor CO2 concentrations in an office environment increases the transcutaneous CO2 level and sleepiness during cognitive work.

PubMed

Vehviläinen, Tommi; Lindholm, Harri; Rintamäki, Hannu; Pääkkönen, Rauno; Hirvonen, Ari; Niemi, Olli; Vinha, Juha

2016-01-01

The purpose of this study is to perform a multiparametric analysis on the environmental factors, the physiological stress reactions in the body, the measured alertness, and the subjective symptoms during simulated office work. Volunteer male subjects were monitored during three 4-hr work meetings in an office room, both in a ventilated and a non-ventilated environment. The environmental parameters measured included CO(2), temperature, and relative humidity. The physiological test battery consisted of measuring autonomic nervous system functions, salivary stress hormones, blood's CO(2)- content and oxygen saturation, skin temperatures, thermal sensations, vigilance, and sleepiness. The study shows that we can see physiological changes caused by high CO(2) concentration. The findings support the view that low or moderate level increases in concentration of CO(2) in indoor air might cause elevation in the blood's transcutaneously assessed CO(2). The observed findings are higher CO(2) concentrations in tissues, changes in heart rate variation, and an increase of peripheral blood circulation during exposure to elevated CO(2) concentration. The subjective parameters and symptoms support the physiological findings. This study shows that a high concentration of CO(2) in indoor air seem to be one parameter causing physiological effects, which can decrease the facility user's functional ability. The correct amount of ventilation with relation to the number of people using the facility, functional air distribution, and regular breaks can counteract the decrease in functional ability. The findings of the study suggest that merely increasing ventilation is not necessarily a rational solution from a technical-economical viewpoint. Instead or in addition, more comprehensive, anthropocentric planning of space is needed as well as instructions and new kinds of reference values for the design and realization of office environments.

THYROID HORMONE REVERSES AGING-INDUCED MYOCARDIAL FATTY ACID OXIDATION DEFECTS AND IMPROVES THE RESPONSE TO ACUTELY INCREASED AFTERLOAD

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

Ledee, Dolena; Portman, Michael A.; Kajimoto, Masaki

Background: Subclinical hypothyroidism occurs during aging in humans and mice and may contribute to development of heart failure. Aging also impairs myocardial fatty acid oxidation, causing increased reliance on flux through pyruvate dehydrogenase (PDH) to maintain function. We hypothesize that the metabolic changes in aged hearts make them less tolerant to acutely increased work and that thyroid hormone reverses these defects. Methods: Studies were performed on young (Young, 4-6 months) and aged (Old, 22-24 months) C57/BL6 mice at standard (50 mmHg) and high afterload (80 mmHg). Another aged group received thyroid hormone for 3 weeks (Old-TH, high afterload only). Functionmore » was measured in isolated working hearts along with substrate fractional contributions (Fc) to the citric acid cycle (CAC) using perfusate with 13C labeled lactate, pyruvate, glucose and unlabeled palmitate and insulin. Results: Cardiac function was similar between Young and Old mice at standard afterload. Palmitate Fc was reduced but no individual carbohydrate contributions differed. CAC and individual substrate fluxes decreased in aged. At high afterload, -dP/dT was decreased in Old versus Young. Similar to low afterload, palmitate Fc was decreased in Old. Thyroid hormone reversed aging-induced changes in palmitate Fc and flux while significantly improving cardiac function. Conclusion: The aged heart shows diminished ability to increase cardiac work due to substrate limitations, primarily impaired fatty acid oxidation. The heart accommodates slightly by increasing efficiency through oxidation of carbohydrate substrates. Thyroid hormone supplementation in aged mice significantly improves cardiac function potentially through restoration of fatty acid oxidation.« less

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.

Non-pharmacological interventions for preventing job loss in workers with inflammatory arthritis.

PubMed

Hoving, Jan L; Lacaille, Diane; Urquhart, Donna M; Hannu, Timo J; Sluiter, Judith K; Frings-Dresen, Monique H W

2014-11-06

Work participation of patients with inflammatory arthritis (IA) is important not only economically but also for physical and psychological health. There is no Cochrane Review to date on studies of non-pharmacological interventions specifically aimed at preventing job loss in people with IA. To assess the effects of non-pharmacological interventions that aim to prevent job loss, work absenteeism or improve work functioning for employees with IA (rheumatoid arthritis (RA), ankylosing spondylitis (AS), psoriatic arthritis (PsA), other spondylarthritis (SpA) or IA associated with connective tissue diseases, such as Systemic Lupus Erythematosus (SLE)). We searched the following databases from inception up to 30 April 2014; The Cochrane Library (including Cochrane Central Register of Controlled Trials, i.e. CENTRAL and DARE), MEDLINE (PubMed), EMBASE (Embase.com), CINAHL (EbSCOhost), ClinicalTrials.gov and PsycINFO (ProQuest). We did not impose language restrictions in the search. We included randomised controlled trials (RCTs) that evaluated interventions aimed at preventing job loss in adults of working age (18 to 65 years) diagnosed with IA, including RA, AS, PsA, SpA or other types of IA. Primary outcomes were job loss and sickness absenteeism and the secondary outcome was work functioning. Two review authors independently selected trials for inclusion, extracted data and assessed risk of bias in the included RCTs. We included three RCTs with a total of 414 participants at risk of job loss. The majority of participants had IA, most with RA and to a lesser degree AS. The interventions aimed to prevent job loss and improve work functioning in several ways: firstly by evaluating work changes or adaptations and secondly by providing any person-directed interventions including vocational counselling, advice or education. Interventions directly targeted at the work environment were minimal and included workplace visits (one trial) or any actions by an occupational physician (one trial). The duration or dose of the interventions varied from two 1.5-hour sessions (one RCT) over five months, two consultation and multidisciplinary treatments during three months (one RCT), to six to eight individual or group sessions over six months (also one RCT). All participants were recruited through rheumatology clinics, both in or outside hospitals. Included trials investigated job loss (n = two RCTs; 382 participants), work absenteeism and work functioning (n = one RCT; 32 participants). Overall, we evaluated the two smaller trials as having a high risk of bias and the large trial as having a low risk of bias. Trials showed marked differences in how they performed on risk of bias items, particularly on performance bias.We assessed the quality of the evidence using the GRADE approach and judged there to be very low quality evidence across the three reported outcomes. Of the two RCTs investigating job loss, the larger one (n = 242 participants) reported a large statistically significant reduction in job loss (relative risk (RR) = 0.35, 95% confidence interval (CI) 0.18 to 0.68) and the other RCT (n = 140) reported similar effects in both groups, although the CI was very wide (RR = 1.05, 95% CI 0.53 to 2.06). The latter one probably suffered from performance bias and we judged it to have a high risk of bias. The one small trial investigating sickness absenteeism found uncertain results at six months' follow-up (MD = -2.42 days, 95% CI -5.03 to 0.19). Finally, in the same small trial investigating work functioning using the Rheumatoid Arthritis-Work Instability Scale (RA-WIS), there was a moderate improvement of intermediate term work functioning (six months; scale range 0 to 23; mean improvement -4.67 points, 95% CI -8.43 to -0.91). We identified no adverse effects in the publications of the three trials. This Cochrane review of three RCTs found very low quality evidence overall for job loss prevention interventions having an effect on job loss, work absenteeism and work functioning in workers with inflammatory arthritis. While this review highlights that further high quality RCTs are required, the results suggest that these strategies have potential to be effective.

Searches for New Physics Using High Mass Dimuons at the CDF II Experiment

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

Karagoz Unel, Muge

2004-12-01

This work describes the measurement of inclusive jets cross section in the D0 experiment. This cross section is computed as a function of jet transverse momentum, in several rapidity intervals. This quantity is sensitive to the proton structure and is crucial for the determination of parton distribution functions (PDF), essentially for the gluon at high proton momentum fraction. The measurement presented here gives the first values obtained for Tevatron Run II for the cross section in several rapidity intervals, for an integrated luminosity of 143 pb -1. The results are in agreement, within the uncertainties, with theoretical Standard Model predictions,more » showing no evidence for new physics. This work points out the aspects of the detector which need better understanding to reach Run I precision and to constrain the PDFs.« less

Back-gated graphene anode for more efficient thermionic energy converters

DOE PAGES

Yuan, Hongyuan; Riley, Daniel C.; Shen, Zhi-Xun; ...

2016-12-15

Thermionic energy converters (TECs) are a direct heat-to-electricity conversion technology with great potential for high efficiency and scalability. However, space charge barrier in the inter-electrode gap and high anode work function are major obstacles toward realizing high efficiency. Here, we demonstrate for the first time a prototype TEC using a back-gated graphene anode, a barium dispenser cathode, and a controllable inter-electrode gap as small as 17 µm, which simultaneously addresses these two obstacles. This leads to an electronic conversion efficiency of 9.8% at cathode temperature of 1000 °C, the highest reported by far. We first demonstrate that electrostatic gating ofmore » graphene by a 20 nm HfO 2 dielectric layer changes the graphene anode work function by 0.63 eV, as observed from the current-voltage characteristics of the TEC. Next, we show that the efficiency increases by a factor of 30.6 by reducing the gap from 1 mm down to 17 µm, after a mono-layer of Ba is deposited on graphene by the dispenser cathode. Lastlu, we show that electrostatic gating of graphene further reduces the graphene work function from 1.85 to 1.69 eV, leading to an additional 67% enhancement in TEC efficiency. Note that the overall efficiency using the back-gated graphene anode is 6.7 times higher compared with that of a TEC with a tungsten anode and the same inter-electrode gap.« less

Back-gated graphene anode for more efficient thermionic energy converters

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

Yuan, Hongyuan; Riley, Daniel C.; Shen, Zhi-Xun

Thermionic energy converters (TECs) are a direct heat-to-electricity conversion technology with great potential for high efficiency and scalability. However, space charge barrier in the inter-electrode gap and high anode work function are major obstacles toward realizing high efficiency. Here, we demonstrate for the first time a prototype TEC using a back-gated graphene anode, a barium dispenser cathode, and a controllable inter-electrode gap as small as 17 µm, which simultaneously addresses these two obstacles. This leads to an electronic conversion efficiency of 9.8% at cathode temperature of 1000 °C, the highest reported by far. We first demonstrate that electrostatic gating ofmore » graphene by a 20 nm HfO 2 dielectric layer changes the graphene anode work function by 0.63 eV, as observed from the current-voltage characteristics of the TEC. Next, we show that the efficiency increases by a factor of 30.6 by reducing the gap from 1 mm down to 17 µm, after a mono-layer of Ba is deposited on graphene by the dispenser cathode. Lastlu, we show that electrostatic gating of graphene further reduces the graphene work function from 1.85 to 1.69 eV, leading to an additional 67% enhancement in TEC efficiency. Note that the overall efficiency using the back-gated graphene anode is 6.7 times higher compared with that of a TEC with a tungsten anode and the same inter-electrode gap.« less

Versatile Synthesis of Amino Acid Functional Polymers without Protection Group Chemistry.

PubMed

Brisson, Emma R L; Xiao, Zeyun; Franks, George V; Connal, Luke A

2017-01-09

The copolymerization of N-isopropylacrylamide (NiPAm) with aldehyde functional monomers facilitates postpolymerization functionalization with amino acids via reductive amination, negating the need for protecting groups. In reductive amination, the imine formed from the condensation reaction between an amine and an aldehyde is reduced to an amine. In this work, we categorize amino acids into four classes based on the functionality of their side chains (acidic, polar neutral, neutral, and basic) and use their amine groups in condensation reactions with aldehyde functional polymers. The dynamic nature of the imine as well as the versatility of reductive amination to functionalize a polymer with a range of amino acids is highlighted. In this manner, amino acid functional polymers are synthesized without the use of protecting groups with high yields, demonstrating the high functional group tolerance of carbonyl condensation chemistry and the subsequent reduction of the imine. Prior to the reduction of the imine bond, transimination reactions are used to demonstrate dynamic polymers that shuffle from a glycine- to a histidine-functional polymer.

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.

Does social support from family and friends work as a buffer against reactions to stressful life events such as terminal cancer?

PubMed

Ringdal, Gerd Inger; Ringdal, Kristen; Jordhøy, Marit S; Kaasa, Stein

2007-03-01

To examine the relationship between social support and emotional functioning and stress reactions. Our hypothesis is that patients who reported a high degree of social support will experience better emotional functioning and less serious stress reactions than patients with a low degree of social support. The sample was comprised of 434 patients at the Palliative Medicine Unit (PMU), University Hospital of Trondheim in Norway. The patients completed a questionnaire monthly including questions about social support from the MacAdam's Scale, subjective stress measured by the Impact of Event Scale (IES), and emotional functioning measured by the subscale in the EORTC QLQ-30. Although our hypothesis was not supported at the baseline assessment, it was supported at the second assessment, 2 months later. Patients with high social support reported better emotional functioning and less serious stress reactions, in terms of lower scores on the IES avoidance subscale, than patients with a low degree of social support. SIGNIFICANCE OF THE RESULTS: The mixed findings may indicate that social support has only small effects on emotional functioning and stress reactions. Our results on the second assessment indicate, however, that social support might work as a buffer against reactions toward external stressful events such as terminal cancer.

Histology Atlas of the Developing Mouse Hepatobiliary System with Emphasis on Embryonic Days 9.5-18.5

PubMed Central

Crawford, Laura Wilding; Foley, Julie F.; Elmore, Susan A.

2012-01-01

Animal model phenotyping, in utero exposure toxiciy studies, and investigation into causes of embryonic, fetal, or perinatal deaths have required pathologists to recognize and diagnose developmental disorders in spontaneous and engineered mouse models of disease. In mammals, the liver is the main site of hematopoiesis during fetal development, has endocrine and exocrine functions important for maintaining homeostasis in fetal and adult life; and performs other functions including waste detoxification, production and removal of glucose, glycogen storage, triglyceride and fatty acid processing, and serum protein production. Due to its role in many critical functions, alterations in the size, morphology, or function(s) of the liver often lead to embryonic lethality. Many publications and websites describe individual aspects of hepatobiliary development at defined stages. However, no single resource provides a detailed histological evaluation of H&E-stained sections of the developing murine liver and biliary systems using high-magnification and high-resolution color images. The work herein provides a histology atlas of hepatobiliary development between embryonic days 9.5-18.5. Although the focus of this work is normal hepatobiliary development, common defects in liver development are also described as a reference for pathologists who may be asked to phenotype mice with congenital, inherited, or treatment-related hepatobiliary defects. PMID:20805319

Academic stress and active learning of nursing students: A cross-sectional study.

PubMed

Magnavita, Nicola; Chiorri, Carlo

2018-06-08

The active role of nursing students is particularly important in the delivery of health care, since playing an active role at the bedside and the use of active and collaborative engagement of students in the nursing activities has been associated with improved student learning. This is consistent with Karasek's learning hypothesis, but it has never been tested on nursing students. This study aimed at investigating whether nursing students in high control conditions reported lower levels of work impairment than students in the conditions with low control, compared them with a group of healthcare workers (HCWs), and tested the moderating role of social support at work. 633 nursing students and 160 HCWs completed the Nursing Work Functioning Questionnaire (NWFQ), and the Demand-Control-Support questionnaire (DCS). Results showed that nursing students reported higher levels of work impairment and were less likely to be classified as active (high demand/high control) or low strain (low demand/high control) than HCWs, and that social support at work moderated the association between being in active or low strain condition and work impairment. Programs to enhance the learning of nursing students must not only fight strain and isolation but must also promote active learning, by increasing the control over the job, team work, and support from teachers. Copyright © 2018. Published by Elsevier Ltd.

Recovery to Preinterventional Functioning, Return-to-Work, and Life Satisfaction After Treatment of Unruptured Aneurysms.

PubMed

Backes, Daan; Rinkel, Gabriel J E; van der Schaaf, Irene C; Nij Bijvank, Jenny A; Verweij, Bon H; Visser-Meily, Johanna M A; Post, Marcel W; Algra, Ale; Vergouwen, Mervyn D I

2015-06-01

The eventual goal of preventive treatment of unruptured intracranial aneurysms is to increase the number of life years with high life satisfaction. Insight in the time with reduced functioning, working capacity, and life satisfaction after aneurysm treatment is pivotal to balance the pros and cons of preventive aneurysm occlusion. We sent a questionnaire on time-to-recovery to preintervention functioning and return-to-work and life satisfaction to patients treated for an unruptured aneurysm between 2000 and 2013. Changes in life satisfaction before treatment, during recovery, and at follow-up were assessed with Wilcoxon signed-rank tests. The questionnaire was sent to 159 patients of whom 110 (69%) responded. The mean follow-up time after aneurysm treatment was 6 years (SD 4). Fifty-four patients had endovascular and 56 had microsurgical occlusion. Complete recovery to preintervention functioning was reported by 81% (95% confidence interval [CI], 74-88) of patients, with a median time-to-recovery of 3 months (range 0-48). Complete work recovery was reported by 78% (95% CI, 66-87) of patients. The proportion of patients with high life satisfaction reduced from 76% (95% CI, 67-84) before treatment to 52% (95% CI, 43-61) during the period of recovery (P<0.01) and restored largely at long-term follow-up (67% [95% CI, 59-76], P=0.08). Life satisfaction is significantly reduced during the period of recovery after treatment of unruptured aneurysms. In the long-term, ≈1 out of 5 patients reports incomplete recovery. These treatment effects should be kept in mind when considering preventive aneurysm treatment. Prospective studies are needed to better compare these losses in patients treated for unruptured aneurysms with those who had subarachnoid hemorrhage. © 2015 American Heart Association, Inc.

Reproducibility in Natural Language Processing: A Case Study of Two R Libraries for Mining PubMed/MEDLINE.

PubMed

Cohen, K Bretonnel; Xia, Jingbo; Roeder, Christophe; Hunter, Lawrence E

2016-05-01

There is currently a crisis in science related to highly publicized failures to reproduce large numbers of published studies. The current work proposes, by way of case studies, a methodology for moving the study of reproducibility in computational work to a full stage beyond that of earlier work. Specifically, it presents a case study in attempting to reproduce the reports of two R libraries for doing text mining of the PubMed/MEDLINE repository of scientific publications. The main findings are that a rational paradigm for reproduction of natural language processing papers can be established; the advertised functionality was difficult, but not impossible, to reproduce; and reproducibility studies can produce additional insights into the functioning of the published system. Additionally, the work on reproducibility lead to the production of novel user-centered documentation that has been accessed 260 times since its publication-an average of once a day per library.

[Industrial hygiene for subway train operators].

PubMed

Elizarov, B B; Sin'kov, A V

1995-01-01

Subway train drivers work in specific conditions of underground surroundings, face psychoemotional stress due to high intensity of signals analyzed in short time for the decision, prominent responsibility for passengers' lives. The work is also associated with significant levels of noise, minor artificial illumination, air pollution with dust and unfavorable microclimate. By the end of working shift the drivers demonstrate marked changes in blood pressure, prolonged oculomotor reactions, depressed visual function. Morbidity with transitory disablement is high among the drivers, presenting especially cardiovascular and gastrointestinal diseases. Unfavorable changes of ageing process are seen in the drivers over 35, in age group of 40-49 years (with length of service at least 20 years). The complex investigations helped to elaborate hygienic norms for new subway cars, to base rational schedule ot work and rest for the drivers.

Dosimetric characterization of the (60)Co BEBIG Co0.A86 high dose rate brachytherapy source using PENELOPE.

PubMed

Guerrero, Rafael; Almansa, Julio F; Torres, Javier; Lallena, Antonio M

2014-12-01

(60)Co sources are being used as an alternative to (192)Ir sources in high dose rate brachytherapy treatments. In a recent document from AAPM and ESTRO, a consensus dataset for the (60)Co BEBIG (model Co0.A86) high dose rate source was prepared by using results taken from different publications due to discrepancies observed among them. The aim of the present work is to provide a new calculation of the dosimetric characteristics of that (60)Co source according to the recommendations of the AAPM and ESTRO report. Radial dose function, anisotropy function, air-kerma strength, dose rate constant and absorbed dose rate in water have been calculated and compared to the results of previous works. Simulations using the two different geometries considered by other authors have been carried out and the effect of the cable density and length has been studied. Copyright © 2014 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

Studies of high coverage oxidation of the Cu(100) surface using low energy positrons

NASA Astrophysics Data System (ADS)

Fazleev, N. G.; Maddox, W. B.; Weiss, A. H.

2012-02-01

The study of oxidation of single crystal metal surfaces is important in understanding the corrosive and catalytic processes associated with thin film metal oxides. The structures formed on oxidized transition metal surfaces vary from simple adlayers of chemisorbed oxygen to more complex structures which result from the diffusion of oxygen into subsurface regions. In this work we present the results of theoretical studies of positron surface and bulk states and annihilation probabilities of surface-trapped positrons with relevant core electrons at the oxidized Cu(100) surface under conditions of high oxygen coverage. Calculations are performed for various high coverage missing row structures ranging between 0.50 and 1.50 ML oxygen coverage. The results of calculations of positron binding energy, positron work function, and annihilation characteristics of surface trapped positrons with relevant core electrons as function of oxygen coverage are compared with experimental data obtained from studies of oxidation of the Cu(100) surface using positron annihilation induced Auger electron spectroscopy (PAES).

Extremely efficient flexible organic light-emitting diodes with modified graphene anode

NASA Astrophysics Data System (ADS)

Han, Tae-Hee; Lee, Youngbin; Choi, Mi-Ri; Woo, Seong-Hoon; Bae, Sang-Hoon; Hong, Byung Hee; Ahn, Jong-Hyun; Lee, Tae-Woo

2012-02-01

Although graphene films have a strong potential to replace indium tin oxide anodes in organic light-emitting diodes (OLEDs), to date, the luminous efficiency of OLEDs with graphene anodes has been limited by a lack of efficient methods to improve the low work function and reduce the sheet resistance of graphene films to the levels required for electrodes. Here, we fabricate flexible OLEDs by modifying the graphene anode to have a high work function and low sheet resistance, and thus achieve extremely high luminous efficiencies (37.2 lm W-1 in fluorescent OLEDs, 102.7 lm W-1 in phosphorescent OLEDs), which are significantly higher than those of optimized devices with an indium tin oxide anode (24.1 lm W-1 in fluorescent OLEDs, 85.6 lm W-1 in phosphorescent OLEDs). We also fabricate flexible white OLED lighting devices using the graphene anode. These results demonstrate the great potential of graphene anodes for use in a wide variety of high-performance flexible organic optoelectronics.

One-pot exfoliation, functionalization, and size manipulation of graphene sheets: efficient system for biomedical applications.

PubMed

Bani, Farhad; Bodaghi, Ali; Dadkhah, Abbas; Movahedi, Soodabeh; Bodaghabadi, Narges; Sadeghizadeh, Majid; Adeli, Mohsen

2018-05-01

In this work, we reported a facile method to produce stable aqueous graphene dispersion through direct exfoliation of graphite by modified hyperbranched polyglycerol. Size of graphene sheets was manipulated by simultaneous exfoliation and sonication of graphite, and functionalized graphene sheets with narrow size distribution were obtained. The polyglycerol-functionalized graphene sheets exhibited highly efficient cellular uptake and photothermal conversion, enabling it to serve as a photothermal agent for cancer therapy.

Atomic layer deposited TaCy metal gates: Impact on microstructure, electrical properties, and work function on HfO2 high-k dielectrics

NASA Astrophysics Data System (ADS)

Triyoso, D. H.; Gregory, R.; Schaeffer, J. K.; Werho, D.; Li, D.; Marcus, S.; Wilk, G. D.

2007-11-01

TaCy has been reported to have the appropriate work function for negative metal-oxide semiconductor metal in high-k metal-oxide field-effect transistors. As device size continues to shrink, a conformal deposition for metal gate electrodes is needed. In this work, we report on the development and characterization of a novel TaCy process by atomic layer deposition (ALD). Detailed physical properties of TaCy films are studied using ellipsometry, a four-point probe, Rutherford backscattering spectrometry (RBS), x-ray photoelectron spectroscopy (XPS), and x-ray diffraction (XRD). RBS and XPS analysis indicate that TaCy films are near-stoichiometric, nitrogen free, and have low oxygen impurities. Powder XRD spectra showed that ALD films have a cubic microstructure. XPS carbon bonding studies revealed that little or no glassy carbon is present in the bulk of the film. Excellent electrical properties are obtained using ALD TaCy as a metal gate electrode. Well-behaved capacitance-voltage characteristics with ALD HfO2 gate dielectrics are demonstrated for TaCy thicknesses of 50, 100, and 250 Å. A low fixed charge (˜2-4×10-11 cm-2) is observed for all ALD HfO2/ALD TaCy devices. Increasing the thickness of ALD TaCy results in a decrease in work function (4.77 to 4.54 eV) and lower threshold voltages.

Evolution of high mobility group nucleosome-binding proteins and its implications for vertebrate chromatin specialization.

PubMed

González-Romero, Rodrigo; Eirín-López, José M; Ausió, Juan

2015-01-01

High mobility group (HMG)-N proteins are a family of small nonhistone proteins that bind to nucleosomes (N). Despite the amount of information available on their structure and function, there is an almost complete lack of information on the molecular evolutionary mechanisms leading to their exclusive differentiation. In the present work, we provide evidence suggesting that HMGN lineages constitute independent monophyletic groups derived from a common ancestor prior to the diversification of vertebrates. Based on observations of the functional diversification across vertebrate HMGN proteins and on the extensive silent nucleotide divergence, our results suggest that the long-term evolution of HMGNs occurs under strong purifying selection, resulting from the lineage-specific functional constraints of their different protein domains. Selection analyses on independent lineages suggest that their functional specialization was mediated by bursts of adaptive selection at specific evolutionary times, in a small subset of codons with functional relevance-most notably in HMGN1, and in the rapidly evolving HMGN5. This work provides useful information to our understanding of the specialization imparted on chromatin metabolism by HMGNs, especially on the evolutionary mechanisms underlying their functional differentiation in vertebrates. © The Author 2014. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

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.

Dissociation of working memory processing associated with native and second languages: PET investigation.

PubMed

Kim, Jae-Jin; Kim, Myung Sun; Lee, Jae Sung; Lee, Dong Soo; Lee, Myung Chul; Kwon, Jun Soo

2002-04-01

Verbal working memory plays a significant role in language comprehension and problem-solving. The prefrontal cortex has been suggested as a critical area in working memory. Given that domain-specific dissociations of working memory may exist within the prefrontal cortex, it is possible that there may also be further functional divisions within the verbal working memory processing. While differences in the areas of the brain engaged in native and second languages have been demonstrated, little is known about the dissociation of verbal working memory associated with native and second languages. We have used H2(15)O positron emission tomography in 14 normal subjects in order to identify the neural correlates selectively involved in working memory of native (Korean) and second (English) languages. All subjects were highly proficient in the native language but poorly proficient in the second language. Cognitive tasks were a two-back task for three kinds of visually presented objects: simple pictures, English words, and Korean words. The anterior portion of the right dorsolateral prefrontal cortex and the left superior temporal gyrus were activated in working memory for the native language, whereas the posterior portion of the right dorsolateral prefrontal cortex and the left inferior temporal gyrus were activated in working memory for the second language. The results suggest that the right dorsolateral prefrontal cortex and left temporal lobe may be organized into two discrete, language-related functional systems. Internal phonological processing seems to play a predominant role in working memory processing for the native language with a high proficiency, whereas visual higher order control does so for the second language with a low proficiency. (C)2002 Elsevier Science (USA).

Nebraska State Plan Career Education Project. Final Performance Report for Period Ending June 30, 1977.

ERIC Educational Resources Information Center

Nebraska State Dept. of Education, Lincoln.

The Nebraska state career education plan was developed to assist individuals in developing essential educational and career skills for responsible functioning. The plan, linking the school and work world, extends chronologically: elementary level--career awareness, middle/junior high school level--career exploration, and senior high school…

High-order time-marching reinitialization for regional level-set functions

NASA Astrophysics Data System (ADS)

Pan, Shucheng; Lyu, Xiuxiu; Hu, Xiangyu Y.; Adams, Nikolaus A.

2018-02-01

In this work, the time-marching reinitialization method is extended to compute the unsigned distance function in multi-region systems involving arbitrary number of regions. High order and interface preservation are achieved by applying a simple mapping that transforms the regional level-set function to the level-set function and a high-order two-step reinitialization method which is a combination of the closest point finding procedure and the HJ-WENO scheme. The convergence failure of the closest point finding procedure in three dimensions is addressed by employing a proposed multiple junction treatment and a directional optimization algorithm. Simple test cases show that our method exhibits 4th-order accuracy for reinitializing the regional level-set functions and strictly satisfies the interface-preserving property. The reinitialization results for more complex cases with randomly generated diagrams show the capability our method for arbitrary number of regions N, with a computational effort independent of N. The proposed method has been applied to dynamic interfaces with different types of flows, and the results demonstrate high accuracy and robustness.

Impact of high-κ dielectric and metal nanoparticles in simultaneous enhancement of programming speed and retention time of nano-flash memory

NASA Astrophysics Data System (ADS)

Pavel, Akeed A.; Khan, Mehjabeen A.; Kirawanich, Phumin; Islam, N. E.

2008-10-01

A methodology to simulate memory structures with metal nanocrystal islands embedded as floating gate in a high-κ dielectric material for simultaneous enhancement of programming speed and retention time is presented. The computational concept is based on a model for charge transport in nano-scaled structures presented earlier, where quantum mechanical tunneling is defined through the wave impedance that is analogous to the transmission line theory. The effects of substrate-tunnel dielectric conduction band offset and metal work function on the tunneling current that determines the programming speed and retention time is demonstrated. Simulation results confirm that a high-κ dielectric material can increase programming current due to its lower conduction band offset with the substrate and also can be effectively integrated with suitable embedded metal nanocrystals having high work function for efficient data retention. A nano-memory cell designed with silver (Ag) nanocrystals embedded in Al 2O 3 has been compared with similar structure consisting of Si nanocrystals in SiO 2 to validate the concept.

Electrocortical and ocular indices of attention to fearful and neutral faces presented under high and low working memory load.

PubMed

MacNamara, Annmarie; Schmidt, Joseph; Zelinsky, Gregory J; Hajcak, Greg

2012-12-01

Working memory load reduces the late positive potential (LPP), consistent with the notion that functional activation of the DLPFC attenuates neural indices of sustained attention. Visual attention also modulates the LPP. In the present study, we sought to determine whether working memory load might exert its influence on ERPs by reducing fixations to arousing picture regions. We simultaneously recorded eye-tracking and EEG while participants performed a working memory task interspersed with the presentation of task-irrelevant fearful and neutral faces. As expected, fearful compared to neutral faces elicited larger N170 and LPP amplitudes; in addition, working memory load reduced the N170 and the LPP. Participants made more fixations to arousing regions of neutral faces and faces presented under high working memory load. Therefore, working memory load did not induce avoidance of arousing picture regions and visual attention cannot explain load effects on the N170 and LPP. Copyright © 2012 Elsevier B.V. All rights reserved.

A Dynamic Simulation of Musculoskeletal Function in the Mouse Hindlimb During Trotting Locomotion

PubMed Central

Charles, James P.; Cappellari, Ornella; Hutchinson, John R.

2018-01-01

Mice are often used as animal models of various human neuromuscular diseases, and analysis of these models often requires detailed gait analysis. However, little is known of the dynamics of the mouse musculoskeletal system during locomotion. In this study, we used computer optimization procedures to create a simulation of trotting in a mouse, using a previously developed mouse hindlimb musculoskeletal model in conjunction with new experimental data, allowing muscle forces, activation patterns, and levels of mechanical work to be estimated. Analyzing musculotendon unit (MTU) mechanical work throughout the stride allowed a deeper understanding of their respective functions, with the rectus femoris MTU dominating the generation of positive and negative mechanical work during the swing and stance phases. This analysis also tested previous functional inferences of the mouse hindlimb made from anatomical data alone, such as the existence of a proximo-distal gradient of muscle function, thought to reflect adaptations for energy-efficient locomotion. The results do not strongly support the presence of this gradient within the mouse musculoskeletal system, particularly given relatively high negative net work output from the ankle plantarflexor MTUs, although more detailed simulations could test this further. This modeling analysis lays a foundation for future studies of the control of vertebrate movement through the development of neuromechanical simulations. PMID:29868576

A computational study on the electronic and field emission properties of Mg and Si doped AlN nanocones

NASA Astrophysics Data System (ADS)

Saedi, Leila; Soleymanabadi, Hamed; Panahyab, Ataollah

2018-05-01

Following an experimental work, we explored the effect of replacing an Al atom of an AlN nanocone by Si or Mg atom on its electronic and field emission properties using density functional theory calculations. We found that both Si-doping and Mg-doping increase the electrical conductivity of AlN nanocone, but their influences on the filed emission properties are significantly different. The Si-doping increases the electron concentration of AlN nanocone and results in a large electron mobility and a low work function, whereas Mg-doping leads to a high hole concentration below the conduction level and increases the work function in agreement with the experimental results. It is predicted that Si-doped AlN nanocones show excellent filed emission performance with higher emitted electron current density compared to the pristine AlN nanocone. But the Mg-doping meaningfully decreases the emitted electron current density from the surface of AlN nanocone. The Mg-doping can increase the work function about 41.9% and the Si-doping can decrease it about 6.3%. The Mg-doping and Si-doping convert the AlN nanocone to a p-type and n-type semiconductors, respectively. Our results explain in a molecular level what observed in the experiment.

Microcontact printing of self-assembled monolayers to pattern the light-emission of polymeric light-emitting diodes

NASA Astrophysics Data System (ADS)

Brondijk, J. J.; Li, X.; Akkerman, H. B.; Blom, P. W. M.; de Boer, B.

2009-04-01

By patterning a self-assembled monolayer (SAM) of thiolated molecules with opposing dipole moments on a gold anode of a polymer light-emitting diode (PLED), the charge injection and, therefore, the light-emission of the device can be controlled with a micrometer-scale resolution. Gold surfaces were modified with SAMs based on alkanethiols and perfluorinated alkanethiols, applied by microcontact printing, and their work functions have been measured. The molecules form a chemisorbed monolayer of only ˜1.5 nm on the gold surface, thereby locally changing the work function of the metal. Kelvin probe measurements show that the local work function can be tuned from 4.3 to 5.5 eV, which implies that this anode can be used as a hole blocking electrode or as a hole injecting electrode, respectively, in PLEDs based on poly( p-phenylene vinylene) (PPV) derivatives. By microcontact printing of SAMs with opposing dipole moments, the work function was locally modified and the charge injection in the PLED could be controlled down to the micrometer length scale. Consequently, the local light-emission exhibits a high contrast. Microcontact printing of SAMs is a simple and inexpensive method to pattern, with micrometer resolution, the light-emission for low-end applications like static displays.

Executive function in middle childhood and the relationship with theory of mind.

PubMed

Wilson, Jennifer; Andrews, Glenda; Hogan, Christy; Wang, Si; Shum, David H K

2018-01-01

A group of 126 typically developing children (aged 5-12 years) completed three cool executive function tasks (spatial working memory, stop signal, intra-extra dimensional shift), two hot executive function tasks (gambling, delay of gratification), one advanced theory of mind task (strange stories with high versus low affective tone), and a vocabulary test. Older children performed better than younger children, consistent with the protracted development of hot and cool executive functions and theory of mind. Multiple regression analyses showed that hot and cool executive functions were correlated but they predicted theory of mind in different ways.

Development of Fast and Reliable Free-Energy Density Functional Methods for Simulations of Dense Plasmas from Cold- to Hot-Temperature Regimes

NASA Astrophysics Data System (ADS)

Karasiev, V. V.

2017-10-01

Free-energy density functional theory (DFT) is one of the standard tools in high-energy-density physics used to determine the fundamental properties of dense plasmas, especially in cold and warm regimes when quantum effects are essential. DFT is usually implemented via the orbital-dependent Kohn-Sham (KS) procedure. There are two challenges of conventional implementation: (1) KS computational cost becomes prohibitively expensive at high temperatures; and (2) ground-state exchange-correlation (XC) functionals do not take into account the XC thermal effects. This talk will address both challenges and report details of the formal development of new generalized gradient approximation (GGA) XC free-energy functional which bridges low-temperature (ground state) and high-temperature (plasma) limits. Recent progress on development of functionals for orbital-free DFT as a way to address the second challenge will also be discussed. This material is based upon work supported by the Department of Energy National Nuclear Security Administration under Award Number DE-NA0001944.

U-shaped associations between time in bed and the physical and mental functioning of Japanese civil servants: the roles of work, family, behavioral and sleep quality characteristics.

PubMed

Sekine, M; Tatsuse, T; Cable, N; Chandola, T; Marmot, M

2014-09-01

This study aimed to evaluate (i) whether work, family, behavioral and sleep quality characteristics differ among individuals with different time in bed (TIB), and (ii) whether and how much the U-shaped associations between TIB and health can be explained by these characteristics. Participants were 3510 employees (2371 males and 1139 females) aged 20-65 years working in local government in Japan. They completed a questionnaire regarding work, family, and behavioral characteristics. Sleep quality and physical and mental functioning were evaluated using the Pittsburgh Sleep Quality Index and the Short Form 36. High job demands, long work hours, and high work-family conflict were more prevalent among those with short TIB. Those with long TIB had daily drinking habits. Whereas those with short TIB had poor sleep, mainly due to poor subjective sleep quality and daytime dysfunction, those with long TIB had poor sleep, mainly due to long sleep latency, poor sleep efficiency and sleep disturbances. The U-shaped associations between TIB and poor physical and mental health, with the best health observed in those spending ~8 h in bed, weakened considerably after adjustment for sleep quality, followed by work and family characteristics. After adjusting for behavioral characteristics and long-standing illnesses, the associations hardly changed. The U-shaped associations between TIB and health may be explained by U-shaped associations between TIB and poor sleep and psychosocial stress in work and family life. Copyright © 2014 Elsevier B.V. All rights reserved.

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

Ali, Amjad Majid; Albert, Don; Andersson, Par

SLURM is an open source, fault-tolerant, and highly scalable cluster management and job scheduling system for large and small computer clusters. As a cluster resource manager, SLURM has three key functions. First, it allocates exclusive and/or non-exclusive access to resources (compute nodes) to users for some duration of time so they can perform work. Second, it provides a framework for starting, executing, and monitoring work 9normally a parallel job) on the set of allocated nodes. Finally, it arbitrates conflicting requests for resources by managing a queue of pending work.

Interprocess Communication in Highly Distributed Systems - A Workshop Report - 20 to 22, November 1978.

DTIC Science & Technology

1979-12-01

Links between processes can be aLlocated strictLy to controL functions. In fact, the degree of separation of control and data is an important research is...delays or Loss of control messages. Cognoscienti agree that message-passing IPC schemes are equivalent in "power" to schemes which employ shared...THEORETICAL WORK Page 55 SECTION 6 THEORETICAL WORK 6.1 WORKING GRUP JIM REP.OR STRUCTURE of Discussion: Distributed system without central (or any) control

Total Quality Management: Will It Work in the System Program Office?

DTIC Science & Technology

1990-05-01

Quality Management (TQM) is a relatively new philosophy of management which has high-level Department of Defense support and is presently being implemented in the Air Force. In the Air Force Systems Command, weapon system development and acquisition are carried out in System Program Offices (SPOs), staffed with various functionally oriented specialists supplied to the System Program Director by functional ’home offices’ via a matrix management scheme. Can TQM, relying as it does on cross-functional cooperation and on processes which cross functional lines, be

Children with low working memory and children with ADHD: same or different?

PubMed

Holmes, Joni; Hilton, Kerry A; Place, Maurice; Alloway, Tracy P; Elliott, Julian G; Gathercole, Susan E

2014-01-01

The purpose of this study was to compare working memory (WM), executive function, academic ability, and problem classroom behaviors in children aged 8-11 years who were either identified via routine screening as having low WM, or had been diagnosed with ADHD. Standardized assessments of WM, executive function and reading and mathematics were administered to 83 children with ADHD, 50 children with low WM and 50 typically developing children. Teachers rated problem behaviors on checklists measuring attention, hyperactivity/impulsivity, oppositional behavior, and difficulties associated with executive function in the classroom. The ADHD and low WM groups had highly similar WM and executive function profiles, but were distinguished in two key respects: children with ADHD had higher levels of rated and observed impulsive behavior, and children with low WM had slower response times. Possible mechanisms for these common and distinct deficits are discussed.

Children with low working memory and children with ADHD: same or different?

PubMed Central

Holmes, Joni; Hilton, Kerry A.; Place, Maurice; Alloway, Tracy P.; Elliott, Julian G.; Gathercole, Susan E.

2014-01-01

The purpose of this study was to compare working memory (WM), executive function, academic ability, and problem classroom behaviors in children aged 8–11 years who were either identified via routine screening as having low WM, or had been diagnosed with ADHD. Standardized assessments of WM, executive function and reading and mathematics were administered to 83 children with ADHD, 50 children with low WM and 50 typically developing children. Teachers rated problem behaviors on checklists measuring attention, hyperactivity/impulsivity, oppositional behavior, and difficulties associated with executive function in the classroom. The ADHD and low WM groups had highly similar WM and executive function profiles, but were distinguished in two key respects: children with ADHD had higher levels of rated and observed impulsive behavior, and children with low WM had slower response times. Possible mechanisms for these common and distinct deficits are discussed. PMID:25538599

Azobenzene-functionalized carbon nanotubes as high-energy density solar thermal fuels.

PubMed

Kolpak, Alexie M; Grossman, Jeffrey C

2011-08-10

Solar thermal fuels, which reversibly store solar energy in molecular bonds, are a tantalizing prospect for clean, renewable, and transportable energy conversion/storage. However, large-scale adoption requires enhanced energy storage capacity and thermal stability. Here we present a novel solar thermal fuel, composed of azobenzene-functionalized carbon nanotubes, with the volumetric energy density of Li-ion batteries. Our work also demonstrates that the inclusion of nanoscale templates is an effective strategy for design of highly cyclable, thermally stable, and energy-dense solar thermal fuels.

U-Shaped and Surface Functionalized Polymer Optical Fiber Probe for Glucose Detection.

PubMed

Azkune, Mikel; Ruiz-Rubio, Leire; Aldabaldetreku, Gotzon; Arrospide, Eneko; Pérez-Álvarez, Leyre; Bikandi, Iñaki; Zubia, Joseba; Vilas-Vilela, Jose Luis

2017-12-25

In this work we show an optical fiber evanescent wave absorption probe for glucose detection in different physiological media. High selectivity is achieved by functionalizing the surface of an only-core poly(methyl methacrylate) (PMMA) polymer optical fiber with phenilboronic groups, and enhanced sensitivity by using a U-shaped geometry. Employing a supercontinuum light source and a high-resolution spectrometer, absorption measurements are performed in the broadband visible light spectrum. Experimental results suggest the feasibility of such a fiber probe as a low-cost and selective glucose detector.

The Development of Metaphor Comprehension and Its Relationship with Relational Verbal Reasoning and Executive Function.

PubMed

Carriedo, Nuria; Corral, Antonio; Montoro, Pedro R; Herrero, Laura; Ballestrino, Patricia; Sebastián, Iraia

2016-01-01

Our main objective was to analyse the different contributions of relational verbal reasoning (analogical and class inclusion) and executive functioning to metaphor comprehension across development. We postulated that both relational reasoning and executive functioning should predict individual and developmental differences. However, executive functioning would become increasingly involved when metaphor comprehension is highly demanding, either because of the metaphors' high difficulty (relatively novel metaphors in the absence of a context) or because of the individual's special processing difficulties, such as low levels of reading experience or low semantic knowledge. Three groups of participants, 11-year-olds, 15-year-olds and young adults, were assessed in different relational verbal reasoning tasks-analogical and class-inclusion-and in executive functioning tasks-updating information in working memory, inhibition, and shifting. The results revealed clear progress in metaphor comprehension between ages 11 and 15 and between ages 15 and 21. However, the importance of executive function in metaphor comprehension was evident by age 15 and was restricted to updating information in working memory and cognitive inhibition. Participants seemed to use two different strategies to interpret metaphors: relational verbal reasoning and executive functioning. This was clearly shown when comparing the performance of the "more efficient" participants in metaphor interpretation with that of the "less efficient" ones. Whereas in the first case none of the executive variables or those associated with relational verbal reasoning were significantly related to metaphor comprehension, in the latter case, both groups of variables had a clear predictor effect.

The effectiveness of high-intensity versus low-intensity back schools in an occupational setting: a pragmatic randomized controlled trial.

PubMed

Heymans, Martijn W; de Vet, Henrica C W; Bongers, Paulien M; Knol, Dirk L; Koes, Bart W; van Mechelen, Willem

2006-05-01

Randomized controlled trial. To compare high- and low-intensity back schools with usual care in occupational health care. The content and intensity of back schools vary widely and the methodologic quality of randomized controlled trials is generally weak. Until now, no back school has proven to be superior for workers sick-listed because of subacute nonspecific low back pain. Workers (n = 299) sick-listed for a period of 3 to 6 weeks because of nonspecific low back pain were recruited by the occupational physician and randomly assigned to a high-intensity back school, a low-intensity back school, or care as usual. Outcome measures were days until return to work, total days of sick-leave, pain, functional status, kinesiophobia, and perceived recovery and were assessed at baseline and at 3 and 6 months of follow-up. Principal analyses were performed according to the intention-to-treat principle. We randomly allocated 299 workers. Workers in the low-intensity back school returned to work faster compared with usual care and the high-intensity back school, with hazard ratios of 1.4 (P = 0.06) and 1.3 (P = 0.09), respectively. The comparison between high-intensity back school and usual care resulted in a hazard ratio of 1.0 (P = 0.83). The median number of sick-leave days was 68, 75, and 85 in the low-intensity back school, usual care, and high-intensity back school, respectively. Beneficial effects on functional status and kinesiophobia were found at 3 months in favor of the low-intensity back school. No substantial differences on pain and perceived recovery were found between groups. The low-intensity back school was most effective in reducing work absence, functional disability, and kinesiophobia, and more workers in this group scored a higher perceived recovery during the 6-month follow-up.

Chemical Approaches for Structure and Function of RNA in Postgenomic Era

PubMed Central

Ro-Choi, Tae Suk; Choi, Yong Chun

2012-01-01

In the study of cellular RNA chemistry, a major thrust of research focused upon sequence determinations for decades. Structures of snRNAs (4.5S RNA I (Alu), U1, U2, U3, U4, U5, and U6) were determined at Baylor College of Medicine, Houston, Tex, in an earlier time of pregenomic era. They show novel modifications including base methylation, sugar methylation, 5′-cap structures (types 0–III) and sequence heterogeneity. This work offered an exciting problem of posttranscriptional modification and underwent numerous significant advances through technological revolutions during pregenomic, genomic, and postgenomic eras. Presently, snRNA research is making progresses involved in enzymology of snRNA modifications, molecular evolution, mechanism of spliceosome assembly, chemical mechanism of intron removal, high-order structure of snRNA in spliceosome, and pathology of splicing. These works are destined to reach final pathway of work “Function and Structure of Spliceosome” in addition to exciting new exploitation of other noncoding RNAs in all aspects of regulatory functions. PMID:22347623

Thermionic converter performance with oxide collectors

NASA Technical Reports Server (NTRS)

Lieb, D.; Goodale, D.; Briere, T.; Balestra, C.

1977-01-01

Thermionic converters using a variety of metal oxide collector surfaces have been fabricated and tested. Both work function and power output data are presented and evaluated. Oxides of barium, strontium, zinc, tungsten and titanium have been incorporated into a variable spacing converter. Tungsten oxide was found to give the highest converter performance and to furnish oxygen for the emitter at the same time. Oxygenated emitters operate at reduced cesium pressure with an increase in electrode spacing. Electron spectroscopy for chemical analysis (ESCA) performed on several tungsten oxide collectors showed cesium penetration of the oxide layer, possibly forming a cesium tungstate bronze. Titanium oxide showed high performance but did not furnish oxygen for the emitter; strontium oxide, in the form of a sprayed layer, appeared to dissociate in the presence of cesium. Sprayed coatings of barium and zinc oxides produced collector work functions of about 1.3 eV, but had excessive series resistance. Lanthanum hexaboride, in combination with oxygen introduced through a silver tube, and cesium produced a low work function collector and better than average performance.

Pattern Genes Suggest Functional Connectivity of Organs

NASA Astrophysics Data System (ADS)

Qin, Yangmei; Pan, Jianbo; Cai, Meichun; Yao, Lixia; Ji, Zhiliang

2016-05-01

Human organ, as the basic structural and functional unit in human body, is made of a large community of different cell types that organically bound together. Each organ usually exerts highly specified physiological function; while several related organs work smartly together to perform complicated body functions. In this study, we present a computational effort to understand the roles of genes in building functional connection between organs. More specifically, we mined multiple transcriptome datasets sampled from 36 human organs and tissues, and quantitatively identified 3,149 genes whose expressions showed consensus modularly patterns: specific to one organ/tissue, selectively expressed in several functionally related tissues and ubiquitously expressed. These pattern genes imply intrinsic connections between organs. According to the expression abundance of the 766 selective genes, we consistently cluster the 36 human organs/tissues into seven functional groups: adipose & gland, brain, muscle, immune, metabolism, mucoid and nerve conduction. The organs and tissues in each group either work together to form organ systems or coordinate to perform particular body functions. The particular roles of specific genes and selective genes suggest that they could not only be used to mechanistically explore organ functions, but also be designed for selective biomarkers and therapeutic targets.

Electronic medical records and physician stress in primary care: results from the MEMO Study

PubMed Central

Babbott, Stewart; Manwell, Linda Baier; Brown, Roger; Montague, Enid; Williams, Eric; Schwartz, Mark; Hess, Erik; Linzer, Mark

2014-01-01

Background Little has been written about physician stress that may be associated with electronic medical records (EMR). Objective We assessed relationships between the number of EMR functions, primary care work conditions, and physician satisfaction, stress and burnout. Design and participants 379 primary care physicians and 92 managers at 92 clinics from New York City and the upper Midwest participating in the 2001–5 Minimizing Error, Maximizing Outcome (MEMO) Study. A latent class analysis identified clusters of physicians within clinics with low, medium and high EMR functions. Main measures We assessed physician-reported stress, burnout, satisfaction, and intent to leave the practice, and predictors including time pressure during visits. We used a two-level regression model to estimate the mean response for each physician cluster to each outcome, adjusting for physician age, sex, specialty, work hours and years using the EMR. Effect sizes (ES) of these relationships were considered small (0.14), moderate (0.39), and large (0.61). Key results Compared to the low EMR cluster, physicians in the moderate EMR cluster reported more stress (ES 0.35, p=0.03) and lower satisfaction (ES −0.45, p=0.006). Physicians in the high EMR cluster indicated lower satisfaction than low EMR cluster physicians (ES −0.39, p=0.01). Time pressure was associated with significantly more burnout, dissatisfaction and intent to leave only within the high EMR cluster. Conclusions Stress may rise for physicians with a moderate number of EMR functions. Time pressure was associated with poor physician outcomes mainly in the high EMR cluster. Work redesign may address these stressors. PMID:24005796

The Relevance of the Functional 5-HT1A Receptor Polymorphism for Attention and Working Memory Processes during Mental Rotation of Characters

ERIC Educational Resources Information Center

Beste, Christian; Heil, Martin; Domschke, Katharina; Konrad, Carsten

2010-01-01

Numerous lines of research indicate that attentional processes, working memory and saccadic processes are highly interrelated. In the current study, we examine the relation between these processes with respect to their cognitive-neurophysiological and neurobiological background by means of event-related potentials (ERPs) in a sample of N = 72…

Youth Apprenticeships and School-to-Work Transition: Current Knowledge and Legislative Strategy. EQW Working Papers.

ERIC Educational Resources Information Center

Osterman, Paul; Iannozzi, Maria

For many youths, the early years in the labor market are characterized not by an absence of jobs but rather by a "churning" process that often delays the benefits of high school educational experiences for several years. Youth apprenticeship programs should be designed to serve as a strategy/vehicle of school reform, function as a labor market…

Impact of Group Work and Extended Essay Writing on Online Advanced Placement Program® Student Performance. Research Report. ETS RR-07-22

ERIC Educational Resources Information Center

Handwerk, Phil

2007-01-01

Online high schools are growing significantly in number, popularity, and function. However, little empirical data has been published about the effectiveness of these institutions. This research examined the frequency of group work and extended essay writing among online Advanced Placement Program® (AP®) students, and how these tasks may have…

Continued Development of Expert System Tools for NPSS Engine Diagnostics

NASA Technical Reports Server (NTRS)

Lewandowski, Henry

1996-01-01

The objectives of this grant were to work with previously developed NPSS (Numerical Propulsion System Simulation) tools and enhance their functionality; explore similar AI systems; and work with the High Performance Computing Communication (HPCC) K-12 program. Activities for this reporting period are briefly summarized and a paper addressing the implementation, monitoring and zooming in a distributed jet engine simulation is included as an attachment.

Successful Training of Filtering Mechanisms in Multiple Object Tracking Does Not Transfer to Filtering Mechanisms in a Visual Working Memory Task: Behavioral and Electrophysiological Evidence

ERIC Educational Resources Information Center

Arend, Anna M.; Zimmer, Hubert D.

2012-01-01

In this training study, we aimed to selectively train participants' filtering mechanisms to enhance visual working memory (WM) efficiency. The highly restricted nature of visual WM capacity renders efficient filtering mechanisms crucial for its successful functioning. Filtering efficiency in visual WM can be measured via the lateralized change…

Bio-psychosocial determinants of time lost from work following non life threatening acute orthopaedic trauma

PubMed Central

2010-01-01

Background To determine factors predicting the duration of time away from work following acute orthopaedic non life threatening trauma Methods Prospective cohort study conducted at four hospitals in Victoria, Australia. The cohort comprised 168 patients aged 18-64 years who were working prior to the injury and sustained a range of acute unintentional orthopaedic injuries resulting in hospitalization. Baseline data was obtained by survey and medical record review. Multivariate Cox proportional hazards regression analysis was used to examine the association between potential predictors and the duration of time away from work during the six month study. The study achieved 89% follow-up. Results Of the 168 participants recruited to the study, 68% returned to work during the six month study. Multivariate Cox proportional hazards regression analysis identified that blue collar work, negative pain attitudes with respect to work, high initial pain intensity, injury severity, older age, initial need for surgery, the presence of co-morbid health conditions at study entry and an orthopaedic injury to more than one region were associated with extended duration away from work following the injury. Participants in receipt of compensation who reported high social functioning at two weeks were 2.58 times more likely to have returned to work than similar participants reporting low social functioning. When only those who had returned to work were considered, the participant reported reason for return to work " to fill the day" was a significant predictor of earlier RTW [RR 2.41 (95% C.I 1.35-4.30)] whereas "financial security" and "because they felt able to" did not achieve significance. Conclusions Many injury-related and psycho social factors affect the duration of time away from work following orthopaedic injury. Some of these are potentially modifiable and may be amenable to intervention. Further consideration of the reasons provided by participants for returning to work may provide important opportunities for social marketing approaches designed to alleviate the financial and social burden associated with work disability. PMID:20051124

Bio-psychosocial determinants of time lost from work following non life threatening acute orthopaedic trauma.

PubMed

Clay, Fiona J; Newstead, Stuart V; Watson, Wendy L; Ozanne-Smith, Joan; McClure, Roderick J

2010-01-05

To determine factors predicting the duration of time away from work following acute orthopaedic non life threatening trauma Prospective cohort study conducted at four hospitals in Victoria, Australia. The cohort comprised 168 patients aged 18-64 years who were working prior to the injury and sustained a range of acute unintentional orthopaedic injuries resulting in hospitalization. Baseline data was obtained by survey and medical record review. Multivariate Cox proportional hazards regression analysis was used to examine the association between potential predictors and the duration of time away from work during the six month study. The study achieved 89% follow-up. Of the 168 participants recruited to the study, 68% returned to work during the six month study. Multivariate Cox proportional hazards regression analysis identified that blue collar work, negative pain attitudes with respect to work, high initial pain intensity, injury severity, older age, initial need for surgery, the presence of co-morbid health conditions at study entry and an orthopaedic injury to more than one region were associated with extended duration away from work following the injury. Participants in receipt of compensation who reported high social functioning at two weeks were 2.58 times more likely to have returned to work than similar participants reporting low social functioning. When only those who had returned to work were considered, the participant reported reason for return to work " to fill the day" was a significant predictor of earlier RTW [RR 2.41 (95% C.I 1.35-4.30)] whereas "financial security" and "because they felt able to" did not achieve significance. Many injury-related and psycho social factors affect the duration of time away from work following orthopaedic injury. Some of these are potentially modifiable and may be amenable to intervention. Further consideration of the reasons provided by participants for returning to work may provide important opportunities for social marketing approaches designed to alleviate the financial and social burden associated with work disability.

Air stable organic-inorganic nanoparticles hybrid solar cells

DOEpatents

Qian, Lei; Yang, Jihua; Xue, Jiangeng; Holloway, Paul H.

2015-09-29

A solar cell includes a low work function cathode, an active layer of an organic-inorganic nanoparticle composite, a ZnO nanoparticle layer situated between and physically contacting the cathode and active layers; and a transparent high work function anode that is a bilayer electrode. The inclusion of the ZnO nanoparticle layer results in a solar cell displaying a conversion efficiency increase and reduces the device degradation rate. Embodiments of the invention are directed to novel ZnO nanoparticles that are advantageous for use as the ZnO nanoparticle layers of the novel solar cells and a method to prepare the ZnO nanoparticles.

Compressive Detection of Highly Overlapped Spectra Using Walsh-Hadamard-Based Filter Functions.

PubMed

Corcoran, Timothy C

2018-03-01

In the chemometric context in which spectral loadings of the analytes are already known, spectral filter functions may be constructed which allow the scores of mixtures of analytes to be determined in on-the-fly fashion directly, by applying a compressive detection strategy. Rather than collecting the entire spectrum over the relevant region for the mixture, a filter function may be applied within the spectrometer itself so that only the scores are recorded. Consequently, compressive detection shrinks data sets tremendously. The Walsh functions, the binary basis used in Walsh-Hadamard transform spectroscopy, form a complete orthonormal set well suited to compressive detection. A method for constructing filter functions using binary fourfold linear combinations of Walsh functions is detailed using mathematics borrowed from genetic algorithm work, as a means of optimizing said functions for a specific set of analytes. These filter functions can be constructed to automatically strip the baseline from analysis. Monte Carlo simulations were performed with a mixture of four highly overlapped Raman loadings and with ten excitation-emission matrix loadings; both sets showed a very high degree of spectral overlap. Reasonable estimates of the true scores were obtained in both simulations using noisy data sets, proving the linearity of the method.

Topographical memory for newly-learned maps is differentially affected by route-based versus landmark-based learning: a functional MRI study.

PubMed

Beatty, Erin L; Muller-Gass, Alexandra; Wojtarowicz, Dorothy; Jobidon, Marie-Eve; Smith, Ingrid; Lam, Quan; Vartanian, Oshin

2018-04-11

Humans rely on topographical memory to encode information about spatial aspects of environments. However, even though people adopt different strategies when learning new maps, little is known about the impact of those strategies on topographical memory, and their neural correlates. To examine that issue, we presented participants with 40 unfamiliar maps, each of which displayed one major route and three landmarks. Half were instructed to memorize the maps by focusing on the route, whereas the other half memorized the maps by focusing on the landmarks. One day later, the participants were tested on their ability to distinguish previously studied 'old' maps from completely unfamiliar 'new' maps under conditions of high and low working memory load in the functional MRI scanner. Viewing old versus new maps was associated with relatively greater activation in a distributed set of regions including bilateral inferior temporal gyrus - an important region for recognizing visual objects. Critically, whereas the performance of participants who had followed a route-based strategy dropped to chance level under high working memory load, participants who had followed a landmark-based strategy performed at above chance levels under both high and low working memory load - reflected by relatively greater activation in the left inferior parietal lobule (i.e. rostral part of the supramarginal gyrus known as area PFt). Our findings suggest that landmark-based learning may buffer against the effects of working memory load during recognition, and that this effect is represented by the greater involvement of a brain region implicated in both topographical and working memory.

CdTe layer structures for X-ray and gamma-ray detection directly grown on the Medipix readout-chip by MBE

NASA Astrophysics Data System (ADS)

Vogt, A.; Schütt, S.; Frei, K.; Fiederle, M.

2017-11-01

This work investigates the potential of CdTe semiconducting layers used for radiation detection directly deposited on the Medipix readout-chip by MBE. Due to the high Z-number of CdTe and the low electron-hole pair creation energy a thin layer suffices for satisfying photon absorption. The deposition takes place in a modified MBE system enabling growth rates up to 10 μm/h while the UHV conditions allow the required high purity for detector applications. CdTe sensor layers deposited on silicon substrates show resistivities up to 5.8 × 108 Ω cm and a preferred (1 1 1) orientation. However, the resistivity increases with higher growth temperature and the orientation gets more random. Additionally, the deposition of a back contact layer sequence in one process simplifies the complex production of an efficient contact on CdTe with aligned work functions. UPS measurements verify a decrease of the work function of 0.62 eV induced by Te doping of the CdTe.

[ROLE OF THE SYMPATHOADRENOMEDULLARY SYSTEM IN FORMATION OF PILOT'S ADAPTATION TO FLIGHT LOADS].

PubMed

Sukhoterin, A F; Pashchenko, P S; Plakhov, N N; Zhuravlev, A G

2015-01-01

Purpose of the work was to evaluate the sympathoadrenomedullary functions and associated psychophysiological reactions of pilots as a function of flight hours on highly maneuverable aircraft. Volunteers to the investigation were 78 pilots (41 pilots of maneuverable aircraft and 37 pilots of bombers and transporters). Selected methods were to enable comprehensive evaluation of the body functioning against flight loads. Our results evidence that piloting of high maneuverable aircraft but not of bombing and transporting aircrafts activates the sympathoadrenomedullary system significantly. This is particularly common to young pilots with the total flying time less than 1000 hours. Adaptive changes to flight factors were noted to develop with age and experience.

Highly efficient inverted polymer solar cells based on a cross-linkable water-/alcohol-soluble conjugated polymer interlayer.

PubMed

Zhang, Kai; Zhong, Chengmei; Liu, Shengjian; Mu, Cheng; Li, Zhengke; Yan, He; Huang, Fei; Cao, Yong

2014-07-09

A cross-linkable water/alcohol soluble conjugated polymer (WSCP) material poly[9,9-bis(6'-(N,N-diethylamino)propyl)-fluorene-alt-9,9-bis(3-ethyl(oxetane-3-ethyloxy)-hexyl) fluorene] (PFN-OX) was designed. The cross-linkable nature of PFN-OX is good for fabricating inverted polymer solar cells (PSCs) with well-defined interface and investigating the detailed working mechanism of high-efficiency inverted PSCs based on poly[4,8-bis(2-ethylhexyloxyl)benzo[1,2-b:4,5-b']dithio-phene-2,6-diyl-alt-ethylhexyl-3-fluorothithieno[3,4-b]thiophene-2-carboxylate-4,6-diyl] (PTB7) and (6,6)-phenyl-C71-butyric acid methyl ester (PC71BM) blend active layer. The detailed working mechanism of WSCP materials in high-efficiency PSCs were studied and can be summarized into the following three effects: a) PFN-OX tunes cathode work function to enhance open-circuit voltage (Voc); b) PFN-OX dopes PC71BM at interface to facilitate electron extraction; and c) PFN-OX extracts electrons and blocks holes to enhance fill factor (FF). On the basis of this understanding, the hole-blocking function of the PFN-OX interlayer was further improved with addition of a ZnO layer between ITO and PFN-OX, which led to inverted PSCs with a power conversion efficiency of 9.28% and fill factor high up to 74.4%.

Functional roles of the cingulo-frontal network in performance on working memory.

PubMed

Kondo, Hirohito; Morishita, Masanao; Osaka, Naoyuki; Osaka, Mariko; Fukuyama, Hidenao; Shibasaki, Hiroshi

2004-01-01

We examined the relationship between brain activities and task performance on working memory. A large-scale study was initially administered to identify good and poor performers using the operation span and reading span tasks. On the basis of those span scores, we divided 20 consenting participants into high- and low-span groups. In an fMRI study, the participants performed verification of arithmetic problems and retention of target words either concurrently or separately. The behavioral results showed that performance was better in the high-span group than in the low-span group under a dual-task condition, but not under two single-task conditions. The anterior cingulate cortex (ACC), left prefrontal cortex (PFC), left inferior frontal cortex, and bilateral parietal cortex were primarily activated for both span groups. We found that signal changes in the ACC were greater in the high-span group than in the low-span group under the dual-task condition, but not under the single-task conditions. Structural equation modeling indicated that an estimate of effective connectivity from the ACC to the left PFC was positive for the high-span group and negative for the-low span group, suggesting that closer cooperation between the two brain regions was strongly related to working memory performance. We conclude that central executive functioning for attention shifting is modulated by the cingulo-frontal network.

Theoretical studies of thermionic conversion of solar energy with graphene as emitter and collector

NASA Astrophysics Data System (ADS)

Olawole, Olukunle C.; De, Dilip Kumar

2018-01-01

Thermionic energy conversion (TEC) using nanomaterials is an emerging field of research. It is known that graphene can withstand temperatures as high as 4600 K in vacuum, and it has been shown that its work function can be engineered from a high value (for monolayer/bilayer) of 4.6 eV to as low as 0.7 eV. Such attractive electronic properties (e.g., good electrical conductivity and high dielectric constant) make engineered graphene a good candidate as an emitter and collector in a thermionic energy converter for harnessing solar energy efficiently. We have used a modified Richardson-Dushman equation and have adopted a model where the collector temperature could be controlled through heat extraction in a calculated amount and a magnet can be attached on the back surface of the collector for future control of the space-charge effect. Our work shows that the efficiency of solar energy conversion also depends on power density falling on the emitter surface, and that a power conversion efficiency of graphene-based solar TEC as high as 55% can be easily achieved (in the absence of the space-charge effect) through proper choice of work functions, collector temperature, and emissivity of emitter surfaces. Such solar energy conversion would reduce our dependence on silicon solar panels and offers great potential for future renewable energy utilization.

Predicting changes in sleep complaints from baseline values and changes in work demands, work control, and work preoccupation--the WOLF-project.

PubMed

Åkerstedt, Torbjörn; Nordin, Maria; Alfredsson, Lars; Westerholm, Peter; Kecklund, Göran

2012-01-01

Stress as a cause of disturbed sleep is often taken for granted, but the longitudinal evidence is limited. The aim of this study was to evaluate new cases of poor sleep as a function of changes in reported work demands, work control, and work preoccupation. Longitudinal study of change with measures occurring twice within a 5-year interval during a period when the prevalence of impaired sleep was increasing in Sweden. The sample of companies was taken from northern Sweden (Norrland) and included 3637 individuals from the "WOLF Norrland" longitudinal cohort, collected through company health services. During the measurement period, 16% of those studied developed new cases of impaired sleep. Logistic regressions adjusted for demographics, work environment factors, and disturbed sleep at T1 period one showed a significant increase in new cases for high work demands and high work preoccupation (OR=1.37; Ci=1.09-1.72 and OR=1.80; CI=1.42-2.28, respectively). The analysis of change in the predictors showed effects of a change from low to high work demands (OR=1.39; Ci=1.00-1.95) on new cases of impaired sleep. Consistent high work demands (high at both points) showed a similar increase (OR=1.49; Ci=1.06-2.11) but no effect was seen for reduced demands. Change in work preoccupation yielded stronger effects with OR=2.47 (1.78-2.47) for increased work preoccupation and OR=3.79 (2.70-5.31) for consistent high work preoccupation. Also, a reduction in work preoccupation was associated with a reduction in new cases of disturbed sleep. Control at work was not related to sleep. Stratification with respect to gender mainly led to fewer significant results (particularly for women) due to larger confidence intervals. It was concluded that self-reported work preoccupation predicts subsequent impairment of sleep and that increased preoccupation is associated with new cases of impaired sleep. Similar, but weaker, results were obtained for work demands. Copyright © 2011 Elsevier B.V. All rights reserved.

Quantifying Health Status and Function in Marfan Syndrome.

PubMed

Rao, Sandesh S; Venuti, Kristen D; Dietz, Harry C; Sponseller, Paul D

2016-01-01

Two hundred thirty patients were prospectively enrolled in this study and completed various portions of the Short Form 36 and a study-specific questionnaire (visual analog scale 1 to 10, comprising three separate questionnaires) to evaluate quality of life and function in patients with Marfan syndrome. The greatest health concern was cardiac problems (high in 70% of patients), followed by spine issues and generalized fatigue (both high, in 53%). The most severe reported pain involved the back: 105 patients (46%) rated pain as 6 to 10 on the visual analog scale. Among the 72 patients who responded to work life questions, work hours were reduced because of treatment in 59 (82%) or directly because of Marfan syndrome in 29 (40%). Across all Short Form 36 domains, patients scored significantly lower than United States population norms (p<.05); physical health scores were considerably lower than mental health scores.

An extensive investigation of work function modulated trapezoidal recessed channel MOSFET

NASA Astrophysics Data System (ADS)

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

2017-11-01

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

Visual-spatial processing and working-memory load as a function of negative and positive psychotic-like experiences.

PubMed

Abu-Akel, A; Reniers, R L E P; Wood, S J

2016-09-01

Patients with schizophrenia show impairments in working-memory and visual-spatial processing, but little is known about the dynamic interplay between the two. To provide insight into this important question, we examined the effect of positive and negative symptom expressions in healthy adults on perceptual processing while concurrently performing a working-memory task that requires the allocations of various degrees of cognitive resources. The effect of positive and negative symptom expressions in healthy adults (N = 91) on perceptual processing was examined in a dual-task paradigm of visual-spatial working memory (VSWM) under three conditions of cognitive load: a baseline condition (with no concurrent working-memory demand), a low VSWM load condition, and a high VSWM load condition. Participants overall performed more efficiently (i.e., faster) with increasing cognitive load. This facilitation in performance was unrelated to symptom expressions. However, participants with high-negative, low-positive symptom expressions were less accurate in the low VSWM condition compared to the baseline and the high VSWM load conditions. Attenuated, subclinical expressions of psychosis affect cognitive performance that is impaired in schizophrenia. The "resource limitations hypothesis" may explain the performance of the participants with high-negative symptom expressions. The dual-task of visual-spatial processing and working memory may be beneficial to assessing the cognitive phenotype of individuals with high risk for schizophrenia spectrum disorders.

Real-Time State Estimation in a Flight Simulator Using fNIRS

PubMed Central

Gateau, Thibault; Durantin, Gautier; Lancelot, Francois; Scannella, Sebastien; Dehais, Frederic

2015-01-01

Working memory is a key executive function for flying an aircraft. This function is particularly critical when pilots have to recall series of air traffic control instructions. However, working memory limitations may jeopardize flight safety. Since the functional near-infrared spectroscopy (fNIRS) method seems promising for assessing working memory load, our objective is to implement an on-line fNIRS-based inference system that integrates two complementary estimators. The first estimator is a real-time state estimation MACD-based algorithm dedicated to identifying the pilot’s instantaneous mental state (not-on-task vs. on-task). It does not require a calibration process to perform its estimation. The second estimator is an on-line SVM-based classifier that is able to discriminate task difficulty (low working memory load vs. high working memory load). These two estimators were tested with 19 pilots who were placed in a realistic flight simulator and were asked to recall air traffic control instructions. We found that the estimated pilot’s mental state matched significantly better than chance with the pilot’s real state (62% global accuracy, 58% specificity, and 72% sensitivity). The second estimator, dedicated to assessing single trial working memory loads, led to 80% classification accuracy, 72% specificity, and 89% sensitivity. These two estimators establish reusable blocks for further fNIRS-based passive brain computer interface development. PMID:25816347

Study of multi-functional precision optical measuring system for large scale equipment

NASA Astrophysics Data System (ADS)

Jiang, Wei; Lao, Dabao; Zhou, Weihu; Zhang, Wenying; Jiang, Xingjian; Wang, Yongxi

2017-10-01

The effective application of high performance measurement technology can greatly improve the large-scale equipment manufacturing ability. Therefore, the geometric parameters measurement, such as size, attitude and position, requires the measurement system with high precision, multi-function, portability and other characteristics. However, the existing measuring instruments, such as laser tracker, total station, photogrammetry system, mostly has single function, station moving and other shortcomings. Laser tracker needs to work with cooperative target, but it can hardly meet the requirement of measurement in extreme environment. Total station is mainly used for outdoor surveying and mapping, it is hard to achieve the demand of accuracy in industrial measurement. Photogrammetry system can achieve a wide range of multi-point measurement, but the measuring range is limited and need to repeatedly move station. The paper presents a non-contact opto-electronic measuring instrument, not only it can work by scanning the measurement path but also measuring the cooperative target by tracking measurement. The system is based on some key technologies, such as absolute distance measurement, two-dimensional angle measurement, automatically target recognition and accurate aiming, precision control, assembly of complex mechanical system and multi-functional 3D visualization software. Among them, the absolute distance measurement module ensures measurement with high accuracy, and the twodimensional angle measuring module provides precision angle measurement. The system is suitable for the case of noncontact measurement of large-scale equipment, it can ensure the quality and performance of large-scale equipment throughout the process of manufacturing and improve the manufacturing ability of large-scale and high-end equipment.

Sequestration of U(VI) from Acidic, Alkaline, and High Ionic-Strength Aqueous Media by Functionalized Magnetic Mesoporous Silica Nanoparticles: Capacity and Binding Mechanisms

EPA Science Inventory

Uranium (VI) exhibits little adsorption onto sediment minerals in acidic, alkaline or high ionic-strength aqueous media that often occur in U mining or contaminated sites, which makes U(VI) very mobile and difficult to sequester. In this work, magnetic mesoporous silica nanoparti...

Quality of life at sea in Polish seafarer's evaluation.

PubMed

Jeżewska, Maria; Grubman-Nowak, Marta; Moryś, Joanna

2015-01-01

Work at sea is highly burdening, hazardous and stressful. Environmental, physical, and psychosociological factors have a great impact on the seafarer's quality of life and work. The research is a part of a broader psychological project performed on people working at sea in Poland during a period of 2011-2014. This report presents the self-evaluation of life quality conducted by a total of 1,700 Polish seafarers who took part in the study. The average age of the group was 45. Following methods were used: WHOQOL-BREF and the "Survey for people working at sea". Polish seafarers gave the highest rates to their social relationships (16.27), then the psychological functioning (15.62), and environment (15.51). The physical domain gave the lowest rates (14.63). The results have shown that quality of life of Polish seafarers is quite high.

Nicotine effects on brain function and functional connectivity in schizophrenia.

PubMed

Jacobsen, Leslie K; D'Souza, D Cyril; Mencl, W Einar; Pugh, Kenneth R; Skudlarski, Pawel; Krystal, John H

2004-04-15

Nicotine in tobacco smoke can improve functioning in multiple cognitive domains. High rates of smoking among schizophrenic patients may reflect an effort to remediate cognitive dysfunction. Our primary aim was to determine whether nicotine improves cognitive function by facilitating activation of brain regions mediating task performance or by facilitating functional connectivity. Thirteen smokers with schizophrenia and 13 smokers with no mental illness were withdrawn from tobacco and underwent functional magnetic resonance imaging (fMRI) scanning twice, once after placement of a placebo patch and once after placement of a nicotine patch. During scanning, subjects performed an n-back task with two levels of working memory load and of selective attention load. During the most difficult (dichotic 2-back) task condition, nicotine improved performance of schizophrenic subjects and worsened performance of control subjects. Nicotine also enhanced activation of a network of regions, including anterior cingulate cortex and bilateral thalamus, and modulated thalamocortical functional connectivity to a greater degree in schizophrenic than in control subjects during dichotic 2-back task performance. In tasks that tax working memory and selective attention, nicotine may improve performance in schizophrenia patients by enhancing activation of and functional connectivity between brain regions that mediate task performance.

Removing function model and experiments on ultrasonic polishing molding die

NASA Astrophysics Data System (ADS)

Huang, Qitai; Ni, Ying; Yu, Jingchi

2010-10-01

Low temperature glass molding technology is the main method on volume-producing high precision middle and small diameter optical cells in the future. While the accuracy of the molding die will effect the cell precision, so the high precision molding die development is one of the most important part of the low temperature glass molding technology. The molding die is manufactured from high rigid and crisp metal alloy, with the ultrasonic vibration character of high vibration frequency and concentrative energy distribution; abrasive particles will impact the rigid metal alloy surface with very high speed that will remove the material from the work piece. Ultrasonic can make the rigid metal alloy molding die controllable polishing and reduce the roughness and surface error. Different from other ultrasonic fabrication method, untouched ultrasonic polishing is applied on polish the molding die, that means the tool does not touch the work piece in the process of polishing. The abrasive particles vibrate around the balance position with high speed and frequency under the drive of ultrasonic vibration in the liquid medium and impact the workspace surface, the energy of abrasive particles come from ultrasonic vibration, while not from the direct hammer blow of the tool. So a nummular vibrator simple harmonic vibrates on an infinity plane surface is considered as a model of ultrasonic polishing working condition. According to Huygens theory the sound field distribution on a plane surface is analyzed and calculated, the tool removing function is also deduced from this distribution. Then the simple point ultrasonic polishing experiment is proceeded to certificate the theory validity.

Effects of increasing left ventricular filling pressure in patients with acute myocardial infarction

PubMed Central

Russell, Richard O.; Rackley, Charles E.; Pombo, Jaoquin; Hunt, David; Potanin, Constantine; Dodge, Harold T.

1970-01-01

Left ventricular performance in 19 patients with acute myocardial infarction has been evaluated by measuring left ventricular response in terms of cardiac output, stroke volume, work, and power to progressive elevation of filling pressure accomplished by progressive expansion of blood volume with rapid infusion of low molecular weight dextran. Such infusion can elevate the cardiac output, stroke volume, work, and power and thus delineate the function of the left ventricle by Frank-Starling function curves. Left ventricular filling pressure in the range of 20-24 mm Hg was associated with the peak of the curves and when the filling pressure exceeded this range, the curves became flattened or decreased. An increase in cardiac output could be maintained for 4 or more hr. Patients with a flattened function curve had a high mortality in the ensuing 8 wk. The function curve showed improvement in myocardial function during the early convalescence. When left ventricular filling pressure is monitored directly or as pulmonary artery end-diastolic pressure, low molecular weight dextran provides a method for assessment of left ventricular function. Images PMID:5431663

Whole Genome Expression in Peripheral-Blood Samples of Workers Professionally Exposed to Polycyclic Aromatic Hydrocarbons

PubMed Central

Wu, Ming-Tsang; Lee, Tzu-Chi; Su, Hung-Ju; Huang, Jie-Len; Peng, Chiung-Yu; Wang, Weihsin; Chou, Ting-Yu; Lin, Ming-Yen; Lin, Wen-Yi; Huang, Chia-Tsuan; Pan, Chih-Hong; Ho, Chi-Kung

2011-01-01

This study aims to examine global gene expression profiles before and after the work-shift among coke-oven workers (COW). COW work six consecutive days and then take two days off. Two blood and urine samples in each worker were collected before starting to work after two-days off and end-of-shift in the sixth-day work in 2009. Altered gene expressions (ratio of gene expression levels between end-of-shift and pre-shift work) were performed by Human OneArray expression system which probes ∼30,000-transcription expression profiling of human genes. Sixteen workers, all men, were enrolled in this study. Median urinary 1-hydroxypyrene (1OHP) levels (μmole/mole creatinine) in end-of-shift work were significantly higher than those in pre-shift work (2.58 vs. 0.29, p = 0.0002). Among the 20,341 genes which passed experimental quality control, 26 gene expression changes, 7 positive and 19 negative, were highly correlated with across-the-shift urinary 1OHP levels (end-of-shift – pre-shift 1OHP) (p-value < 0.001). The high and low exposure groups of across-the-shift urinary 1OHP levels dichotomized in ∼2.00 μmole/mole creatinine were able to be distinguished by these 26 genes. Some of them are known to be involved in apoptosis, chromosome stability/DNA repair, cell cycle control/tumor suppressor, cell adhesion, development/spermatogenesis, immune function, and neuronal cell function. These findings in COW will be an ideal model to study the relationship of PAHs exposure with acute changes of gene expressions. PMID:21854004

A parallel approach of COFFEE objective function to multiple sequence alignment

NASA Astrophysics Data System (ADS)

Zafalon, G. F. D.; Visotaky, J. M. V.; Amorim, A. R.; Valêncio, C. R.; Neves, L. A.; de Souza, R. C. G.; Machado, J. M.

2015-09-01

The computational tools to assist genomic analyzes show even more necessary due to fast increasing of data amount available. With high computational costs of deterministic algorithms for sequence alignments, many works concentrate their efforts in the development of heuristic approaches to multiple sequence alignments. However, the selection of an approach, which offers solutions with good biological significance and feasible execution time, is a great challenge. Thus, this work aims to show the parallelization of the processing steps of MSA-GA tool using multithread paradigm in the execution of COFFEE objective function. The standard objective function implemented in the tool is the Weighted Sum of Pairs (WSP), which produces some distortions in the final alignments when sequences sets with low similarity are aligned. Then, in studies previously performed we implemented the COFFEE objective function in the tool to smooth these distortions. Although the nature of COFFEE objective function implies in the increasing of execution time, this approach presents points, which can be executed in parallel. With the improvements implemented in this work, we can verify the execution time of new approach is 24% faster than the sequential approach with COFFEE. Moreover, the COFFEE multithreaded approach is more efficient than WSP, because besides it is slightly fast, its biological results are better.

MIPS bacterial genomes functional annotation benchmark dataset.

PubMed

Tetko, Igor V; Brauner, Barbara; Dunger-Kaltenbach, Irmtraud; Frishman, Goar; Montrone, Corinna; Fobo, Gisela; Ruepp, Andreas; Antonov, Alexey V; Surmeli, Dimitrij; Mewes, Hans-Wernen

2005-05-15

Any development of new methods for automatic functional annotation of proteins according to their sequences requires high-quality data (as benchmark) as well as tedious preparatory work to generate sequence parameters required as input data for the machine learning methods. Different program settings and incompatible protocols make a comparison of the analyzed methods difficult. The MIPS Bacterial Functional Annotation Benchmark dataset (MIPS-BFAB) is a new, high-quality resource comprising four bacterial genomes manually annotated according to the MIPS functional catalogue (FunCat). These resources include precalculated sequence parameters, such as sequence similarity scores, InterPro domain composition and other parameters that could be used to develop and benchmark methods for functional annotation of bacterial protein sequences. These data are provided in XML format and can be used by scientists who are not necessarily experts in genome annotation. BFAB is available at http://mips.gsf.de/proj/bfab

Quality engineering tools focused on high power LED driver design using boost power stages in switch mode

NASA Astrophysics Data System (ADS)

Ileana, Ioan; Risteiu, Mircea; Marc, Gheorghe

2016-12-01

This paper is a part of our research dedicated to high power LED lamps designing. The boost-up selected technology wants to meet driver producers' tendency in the frame of efficiency and disturbances constrains. In our work we used modeling and simulation tools for implementing scenarios of the driver work when some controlling functions are executed (output voltage/ current versus input voltage and fixed switching frequency, input and output electric power transfer versus switching frequency, transient inductor voltage analysis, and transient out capacitor analysis). Some electrical and thermal stress conditions are also analyzed. Based on these aspects, a high reliable power LED driver has been designed.

WISC-IV and WIAT-II profiles in children with high-functioning autism.

PubMed

Mayes, Susan Dickerson; Calhoun, Susan L

2008-03-01

Children with high-functioning autism earned above normal scores on the Wechsler Intelligence Scale for Children-Fourth Edition (WISC-IV) Perceptual Reasoning and Verbal Comprehension Indexes and below normal scores on the Working Memory and Processing Speed Indexes and Wechsler Individual Achievement Test-Second Edition (WIAT-II) Written Expression. Full Scale IQ (FSIQ) and reading and math scores were similar to the norm. Profiles were consistent with previous WISC-III research, except that the new WISC-IV motor-free visual reasoning subtests (Matrix Reasoning and Picture Concepts) were the highest of the nonverbal subtests. The WISC-IV may be an improvement over the WISC-III for children with high-functioning autism because it captures their visual reasoning strength, while identifying their attention, graphomotor, and processing speed weaknesses. FSIQ was the best single predictor of academic achievement.

The influence of hydrogenation and oxygen vacancies on molybdenum oxides work function and gap states for application in organic optoelectronics.

PubMed

Vasilopoulou, Maria; Douvas, Antonios M; Georgiadou, Dimitra G; Palilis, Leonidas C; Kennou, Stella; Sygellou, Labrini; Soultati, Anastasia; Kostis, Ioannis; Papadimitropoulos, Giorgos; Davazoglou, Dimitris; Argitis, Panagiotis

2012-10-03

Molybdenum oxide is used as a low-resistance anode interfacial layer in applications such as organic light emitting diodes and organic photovoltaics. However, little is known about the correlation between its stoichiometry and electronic properties, such as work function and occupied gap states. In addition, despite the fact that the knowledge of the exact oxide stoichiometry is of paramount importance, few studies have appeared in the literature discussing how this stoichiometry can be controlled to permit the desirable modification of the oxide's electronic structure. This work aims to investigate the beneficial role of hydrogenation (the incorporation of hydrogen within the oxide lattice) versus oxygen vacancy formation in tuning the electronic structure of molybdenum oxides while maintaining their high work function. A large improvement in the operational characteristics of both polymer light emitting devices and bulk heterojunction solar cells incorporating hydrogenated Mo oxides as hole injection/extraction layers was achieved as a result of favorable energy level alignment at the metal oxide/organic interface and enhanced charge transport through the formation of a large density of gap states near the Fermi level.

Cognitive remediation therapy (CRT) benefits more to patients with schizophrenia with low initial memory performances.

PubMed

Pillet, Benoit; Morvan, Yannick; Todd, Aurelia; Franck, Nicolas; Duboc, Chloé; Grosz, Aimé; Launay, Corinne; Demily, Caroline; Gaillard, Raphaël; Krebs, Marie-Odile; Amado, Isabelle

2015-01-01

Cognitive deficits in schizophrenia mainly affect memory, attention and executive functions. Cognitive remediation is a technique derived from neuropsychology, which aims to improve or compensate for these deficits. Working memory, verbal learning, and executive functions are crucial factors for functional outcome. Our purpose was to assess the impact of the cognitive remediation therapy (CRT) program on cognitive difficulties in patients with schizophrenia, especially on working memory, verbal memory, and cognitive flexibility. We collected data from clinical and neuropsychological assessments in 24 patients suffering from schizophrenia (Diagnostic and Statistical Manual of mental Disorders-Fourth Edition, DSM-IV) who followed a 3-month (CRT) program. Verbal and visuo-spatial working memory, verbal memory, and cognitive flexibility were assessed before and after CRT. The Wilcoxon test showed significant improvements on the backward digit span, on the visual working memory span, on verbal memory and on flexibility. Cognitive improvement was substantial when baseline performance was low, independently from clinical benefit. CRT is effective on crucial cognitive domains and provides a huge benefit for patients having low baseline performance. Such cognitive amelioration appears highly promising for improving the outcome in cognitively impaired patients.

Enhanced electron emission from coated metal targets: Effect of surface thickness on performance

NASA Astrophysics Data System (ADS)

Madas, Saibabu; Mishra, S. K.; Upadhyay Kahaly, Mousumi

2018-03-01

In this work, we establish an analytical formalism to address the temperature dependent electron emission from a metallic target with thin coating, operating at a finite temperature. Taking into account three dimensional parabolic energy dispersion for the target (base) material and suitable thickness dependent energy dispersion for the coating layer, Fermi Dirac statistics of electron energy distribution and Fowler's mechanism of the electron emission, we discuss the dependence of the emission flux on the physical properties such as the Fermi level, work function, thickness of the coating material, and operating temperature. Our systematic estimation of how the thickness of coating affects the emission current demonstrates superior emission characteristics for thin coating layer at high temperature (above 1000 K), whereas in low temperature regime, a better response is expected from thicker coating layer. This underlying fundamental behavior appears to be essentially identical for all configurations when work function of the coating layer is lower than that of the bulk target work function. The analysis and predictions could be useful in designing new coated materials with suitable thickness for applications in the field of thin film devices and field emitters.

Scalable Functionalized Graphene Nano-platelets as Tunable Cathodes for High-performance Lithium Rechargeable Batteries

PubMed Central

Kim, Haegyeom; Lim, Hee-Dae; Kim, Sung-Wook; Hong, Jihyun; Seo, Dong-Hwa; Kim, Dae-chul; Jeon, Seokwoo; Park, Sungjin; Kang, Kisuk

2013-01-01

High-performance and cost-effective rechargeable batteries are key to the success of electric vehicles and large-scale energy storage systems. Extensive research has focused on the development of (i) new high-energy electrodes that can store more lithium or (ii) high-power nano-structured electrodes hybridized with carbonaceous materials. However, the current status of lithium batteries based on redox reactions of heavy transition metals still remains far below the demands required for the proposed applications. Herein, we present a novel approach using tunable functional groups on graphene nano-platelets as redox centers. The electrode can deliver high capacity of ~250 mAh g−1, power of ~20 kW kg−1 in an acceptable cathode voltage range, and provide excellent cyclability up to thousands of repeated charge/discharge cycles. The simple, mass-scalable synthetic route for the functionalized graphene nano-platelets proposed in this work suggests that the graphene cathode can be a promising new class of electrode. PMID:23514953

Symptoms of ADHD in children with high-functioning autism are related to impaired verbal working memory and verbal delayed recall.

PubMed

Andersen, Per Normann; Hovik, Kjell Tore; Skogli, Erik Winther; Egeland, Jens; Oie, Merete

2013-01-01

Symptoms similar to those found in Attention-Deficit/Hyperactivity Disorder (ADHD) often occur in children with Autism Spectrum Disorders (ASD). The objective of the current study was to compare verbal working memory, acquisition and delayed recall in children with High-Functioning Autism (HFA) to children with ADHD and typically developing children (TDC). Thirty-eight children with HFA, 79 with ADHD and 50 TDC (age 8-17) were assessed with a letter/number sequencing task and a verbal list-learning task. To investigate the possible influence of attention problems in children with HFA, we divided the HFA group into children with (HFA+) or without (HFA-) "attention problems" according to the Child Behaviour Checklist 6-18. The children with HFA+ displayed significant impairment compared to TDC on all three neurocognitive measures, while the children with HFA- were significantly impaired compared to TDC only on the working memory and acquisition measures. In addition, the HFA+ group scored significantly below the HFA- group and the ADHD group on the verbal working memory and delayed recall measures. The results support the proposition that children with HFA+, HFA-, and ADHD differ not only on a clinical level but also on a neurocognitive level which may have implications for treatment.

Dynamic reconfiguration of frontal brain networks during executive cognition in humans

PubMed Central

Braun, Urs; Schäfer, Axel; Walter, Henrik; Erk, Susanne; Romanczuk-Seiferth, Nina; Haddad, Leila; Schweiger, Janina I.; Grimm, Oliver; Heinz, Andreas; Tost, Heike; Meyer-Lindenberg, Andreas; Bassett, Danielle S.

2015-01-01

The brain is an inherently dynamic system, and executive cognition requires dynamically reconfiguring, highly evolving networks of brain regions that interact in complex and transient communication patterns. However, a precise characterization of these reconfiguration processes during cognitive function in humans remains elusive. Here, we use a series of techniques developed in the field of “dynamic network neuroscience” to investigate the dynamics of functional brain networks in 344 healthy subjects during a working-memory challenge (the “n-back” task). In contrast to a control condition, in which dynamic changes in cortical networks were spread evenly across systems, the effortful working-memory condition was characterized by a reconfiguration of frontoparietal and frontotemporal networks. This reconfiguration, which characterizes “network flexibility,” employs transient and heterogeneous connectivity between frontal systems, which we refer to as “integration.” Frontal integration predicted neuropsychological measures requiring working memory and executive cognition, suggesting that dynamic network reconfiguration between frontal systems supports those functions. Our results characterize dynamic reconfiguration of large-scale distributed neural circuits during executive cognition in humans and have implications for understanding impaired cognitive function in disorders affecting connectivity, such as schizophrenia or dementia. PMID:26324898

The impact of new-generation physicians on the function of academic anesthesiology departments.

PubMed

Kapur, Patricia A

2007-12-01

Academic departments of anesthesiology have had to adapt a wide variety of clinical and educational work functions to the viewpoints, values and normative expectations of the newer generations of physicians who now present themselves for training as well as for faculty employment. This commentary will elaborate on key points that academic departments must recognize and incorporate into their functional and organizational imperatives in order to remain successful with regard to physician recruitment and retention. Recognition of differences between newer-generation vs. established physician issues and concerns include differences in: learning style, teaching style, approach to clinical schedules and the concept of life-work balance, academic and personal motivation, desire for control of their work experience, effective productivity incentives, as well as communication style issues and implications thereof. The spectrum of physicians who contribute to the impact of these factors on contemporary academic anesthesiology departments include faculty, nonfaculty staff physicians, residents and medical students. Academic departments of anesthesiology which can successfully incorporate the changes and most importantly the functional and organizational flexibility needed to respond to the newer generations' worldview and so-called balanced goals will be able to best attract high-caliber housestaff and future faculty.

Productive Activities and Development of Frailty in Older Adults

PubMed Central

Jung, Yunkyung; Gruenewald, Tara L.; Seeman, Teresa E.

2010-01-01

Objective. Our aim was to examine whether engagement in productive activities, including volunteering, paid work, and childcare, protects older adults against the development of geriatric frailty. Methods. Data from the first (1988) and second (1991) waves of the MacArthur Study of Successful Aging, a prospective cohort study of high-functioning older adults aged 70–79 years (n = 1,072), was used to examine the hypothesis that engagement in productive activities is associated with lower levels of frailty 3 years later. Results. Engagement in productive activities at baseline was associated with a lower cumulative odds of frailty 3 years later in unadjusted models (odds ratio [OR] = 0.74, 95% confidence interval [CI] = 0.58–0.96) but not after adjusting for age, disability, and cognitive function (adjusted OR = 0.78, 95% CI = 0.60–1.01). Examination of productive activity domains showed that volunteering (but neither paid work nor childcare) was associated with a lower cumulative odds of frailty after adjusting for age, disability, and cognitive function. This relationship diminished and was no longer statistically significant after adjusting for personal mastery and religious service attendance. Discussion. Though high-functioning older adults who participate in productive activities are less likely to become frail, after adjusting for age, disability, and cognitive function, only volunteering is associated with a lower cumulative odds of frailty. PMID:20018794

The "long tail" of the protein tumbling correlation function: observation by (1)H NMR relaxometry in a wide frequency and concentration range.

PubMed

Roos, Matthias; Hofmann, Marius; Link, Susanne; Ott, Maria; Balbach, Jochen; Rössler, Ernst; Saalwächter, Kay; Krushelnitsky, Alexey

2015-12-01

Inter-protein interactions in solution affect the auto-correlation function of Brownian tumbling not only in terms of a simple increase of the correlation time, they also lead to the appearance of a weak slow component ("long tail") of the correlation function due to a slowly changing local anisotropy of the microenvironment. The conventional protocol of correlation time estimation from the relaxation rate ratio R1/R2 assumes a single-component tumbling correlation function, and thus can provide incorrect results as soon as the "long tail" is of relevance. This effect, however, has been underestimated in many instances. In this work we present a detailed systematic study of the tumbling correlation function of two proteins, lysozyme and bovine serum albumin, at different concentrations and temperatures using proton field-cycling relaxometry combined with R1ρ and R2 measurements. Unlike high-field NMR relaxation methods, these techniques enable a detailed study of dynamics on a time scale longer than the normal protein tumbling correlation time and, thus, a reliable estimate of the parameters of the "long tail". In this work we analyze the concentration dependence of the intensity and correlation time of the slow component and perform simulations of high-field (15)N NMR relaxation data demonstrating the importance of taking the "long tail" in the analysis into account.

L-Band Digital Aeronautical Communications System Engineering - Concepts of Use, Systems Performance, Requirements, and Architectures

NASA Technical Reports Server (NTRS)

Zelkin, Natalie; Henriksen, Stephen

2010-01-01

This NASA Contractor Report summarizes and documents the work performed to develop concepts of use (ConUse) and high-level system requirements and architecture for the proposed L-band (960 to 1164 MHz) terrestrial en route communications system. This work was completed as a follow-on to the technology assessment conducted by NASA Glenn Research Center and ITT for the Future Communications Study (FCS). ITT assessed air-to-ground (A/G) communications concepts of use and operations presented in relevant NAS-level, international, and NAS-system-level documents to derive the appropriate ConUse relevant to potential A/G communications applications and services for domestic continental airspace. ITT also leveraged prior concepts of use developed during the earlier phases of the FCS. A middle-out functional architecture was adopted by merging the functional system requirements identified in the bottom-up assessment of existing requirements with those derived as a result of the top-down analysis of ConUse and higher level functional requirements. Initial end-to-end system performance requirements were derived to define system capabilities based on the functional requirements and on NAS-SR-1000 and the Operational Performance Assessment conducted as part of the COCR. A high-level notional architecture of the L-DACS supporting A/G communication was derived from the functional architecture and requirements.

Visual bottle inspection performance in highly paced belt-conveyor systems.

PubMed

Saito, M; Tanaka, T

1977-12-01

The relation between visual work performance and a few variables with immediate effects, i.e, lighting, work speed, work spell, etc. was studied. At the same time, some physiological and behavioral variations obtained in the study were also discussed. Through experiments and surveys, the optimum conditions were found for each variable. Work performance, however, is affected in such a subtle, interactive and dynamic manner that the working conditions are to be adjusted by taking into account not only these variables having immediate effects but also those indirectly relating ones meeting real needs in the practical working fields. Improvement of some physical working conditions, such as lighting, produces only a transitory increase of performance which is very unstable unless other determinants of performance are simultaneously managed in a proper manner. The same applied to arrangement of the optimum work speed and work spell for highly paced visual inspection, variations in rejection rate and in physiological functions interacting with individual and other determinants. In order to maximize understanding of the integrated and synthesized manner of determinants, it is emphasized that work performance must be pursued in a considerably comprehensive framework from a long-term perspective.

Executive functioning in people with obsessive-compulsive personality traits: evidence of modest impairment.

PubMed

García-Villamisar, Domingo; Dattilo, John

2015-06-01

Investigations of executive dysfunctions among people with obsessive-compulsive personality disorders (OCPD) have yielded inconsistent results. The authors speculate that obsessive-compulsive personality traits (OCPT) from a nonclinical population may be associated with specific executive dysfunctions relative to working memory, attentional set-shifting, and planning. A sample consisting of 79 adults (39 females, 40 males) was divided into high and low scorers on the Personality Diagnostic Questionnaire-4 (PDQ-4; Hyler, 1994). In addition, these participants were interviewed using the SCID-II (First, Spitzer, Gibbon & Williams, 1997) to confirm the presence of symptoms of obsessive-compulsive personality. Participants completed a battery of executive tasks associated with the Cambridge Neuropsychological Test Automated Battery (CANTAB), including Spatial Working Memory, Intradimensional/Extradimensional (ID/ED), Attentional Set-Shifting, and Stockings of Cambridge. Also, self-report measures of executive functions as well as of anxiety and depressive symptoms were administered. The analysis of covariance revealed significant differences between participants with OCPT and controls on the Spatial Working Memory tasks, ID/ED tasks, Stockings of Cambridge, and the Dysexecutive Questionnaire (DEX). Nevertheless, there were no significant differences in the number of problems solved in minimum movements. These results suggest that executive dysfunctions are present in people with prominent OCPT and that there is a high convergence between clinical and ecological measures of executive functions in people with obsessive personality traits.

Materials characterization of impregnated W and W-Ir cathodes after oxygen poisoning

NASA Astrophysics Data System (ADS)

Polk, James E.; Capece, Angela M.

2015-05-01

Electric thrusters use hollow cathodes as the electron source for generating the plasma discharge and for beam neutralization. These cathodes contain porous tungsten emitters impregnated with BaO material to achieve a lower surface work function and are operated with xenon propellant. Oxygen contaminants in the xenon plasma can poison the emitter surface, resulting in a higher work function and increased operating temperature. This could lead directly to cathode failure by preventing discharge ignition or could accelerate evaporation of the BaO material. Exposures over hundreds of hours to very high levels of oxygen can result in increased temperatures, oxidation of the tungsten substrate, and the formation of surface layers of barium tungstates. In this work, we present results of a cathode test in which impregnated tungsten and tungsten-iridium emitters were operated with 100 ppm of oxygen in the xenon plasma for several hundred hours. The chemical and morphological changes were studied using scanning electron microscopy, energy dispersive spectroscopy, and laser profilometry. The results provide strong evidence that high concentrations of oxygen accelerate the formation of tungstate layers in both types of emitters, a phenomenon not inherent to normal cathode operation. Deposits of pure tungsten were observed on the W-Ir emitter, indicating that tungsten is preferentially removed from the surface and transported in the insert plasma. A W-Ir cathode surface will therefore evolve to a pure W composition, eliminating the work function benefit of W-Ir. However, the W-Ir emitter exhibited less erosion and redeposition at the upstream end than the pure W emitter.

Parametric performance of circumferentially grooved heat pipes with homogeneous and graded-porosity slab wicks at cryogenic temperatures. [methane and ethane working fluids

NASA Technical Reports Server (NTRS)

Groll, M.; Pittman, R. B.; Eninger, J. E.

1976-01-01

A recently developed, potentially high-performance nonarterial wick was extensively tested. This slab wick has an axially varying porosity which can be tailored to match the local stress imposed on the wick. The purpose of the tests was to establish the usefulness of the graded-porosity slab wick at cryogenic temperatures between 110 and 260 K, with methane and ethane as working fluids. For comparison, a homogeneous (i.e., uniform porosity) slab wick was also tested. The tests included: maximum heat pipe performance as a function of fluid inventory, maximum performance as a function of operating temperature, maximum performance as a function of evaporator elevation, and influence of slab wick orientation on performance. The experimental data were compared with theoretical predictions obtained with the GRADE computer program.

The Work Disability Functional Assessment Battery (WD-FAB): Feasibility and Psychometric Properties

PubMed Central

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

2015-01-01

Objectives To assess the feasibility and psychometric properties of eight scales covering two domains of the newly developed Work Disability Functional Assessment Battery (WD-FAB): physical function (PF) and behavioral health (BH) function. Design Cross-sectional. Setting Community. Participants Adults unable to work due to a physical (n=497) or mental (n=476) disability. Interventions None. Main Outcome Measures Each disability group responded to a survey consisting of the relevant WD-FAB scales and existing measures of established validity. The WD-FAB scales were evaluated with regard to data quality (score distribution; percent “I don’t know” responses), efficiency of administration (number of items required to achieve reliability criterion; time required to complete the scale) by computerized adaptive testing (CAT), and measurement accuracy as tested by person fit. Construct validity was assessed by examining both convergent and discriminant correlations between the WD-FAB scales and scores on same-domain and cross-domain established measures. Results Data quality was good and CAT efficiency was high across both WD-FAB domains. Measurement accuracy was very good for the PF scales; BH scales demonstrated more variability. Construct validity correlations, both convergent and divergent, between all WD-FAB scales and established measures were in the expected direction and range of magnitude. Conclusions The data quality, CAT efficacy, person fit and construct validity of the WD-FAB scales were well supported and suggest that the WD-FAB could be used to assess physical and behavioral health function related to work disability. Variation in scale performance suggests the need for future work on item replenishment and refinement, particularly regarding the Self-Efficacy scale. PMID:25528263

A new method of functionalized multi walled carbon nanotubes by natural oil for microorganism cells detection

NASA Astrophysics Data System (ADS)

Haider, Adawiya J.; Marzoog, Thorria R.; Hadi, Iman H.; Jameel, Zainab N.

2018-05-01

In this work, new surfactants for Functionalization of Multi Walled Carbon Nanotubes (F-MWCNTs) with functional groups have been developed by using walnut oil, to improve their surface activity (solubility) and a create free reticules (functional groups) on it. MWCNTs were functionalized with walnut oil via ultra-sonication technique at 25°C for 1h with no drastic fragmentation of MWCNTs. Fourier Transformed Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), High Resolution Transmission Electron Microscopy (HRTEM) and have been employed for the characterizations and analysis. In addition, the antibacterial activity of functionalized MWCNTs against Gram negative. Escherichia coli (E. coli) and Gram positive Staphylococcus aureus (S. aureus) bacteria are examined.

Mild Jugular Compression Collar Ameliorated Changes in Brain Activation of Working Memory after One Soccer Season in Female High School Athletes.

PubMed

Yuan, Weihong; Dudley, Jonathan; Barber Foss, Kim D; Ellis, Jonathan D; Thomas, Staci; Galloway, Ryan T; DiCesare, Christopher A; Leach, James L; Adams, Janet; Maloney, Thomas; Gadd, Brooke; Smith, David; Epstein, Jeff N; Grooms, Dustin R; Logan, Kelsey; Howell, David R; Altaye, Mekibib; Myer, Gregory D

2018-06-01

Recent neuroimaging studies have suggested that repetitive subconcussive head impacts, even after only one sport season, may lead to pre- to post-season structural and functional alterations in male high school football athletes. However, data on female athletes are limited. In the current investigation, we aimed to (1) assess the longitudinal pre- to post-season changes in functional MRI (fMRI) of working memory and working memory performance, (2) quantify the association between the pre- to post-season change in fMRI of working memory and the exposure to head impact and working memory performance, and (3) assess whether wearing a neck collar designed to reduce intracranial slosh via mild compression of the jugular veins can ameliorate the changes in fMRI brain activation observed in the female high school athletes who did not wear collars after a full soccer season. A total of 48 female high school soccer athletes (age range: 14.00-17.97 years) were included in the study. These athletes were assigned to the non-collar group (n = 21) or to the collar group (n = 27). All athletes undewent MRI at both pre-season and post-season. In each session, a fMRI verbal N-Back task was used to engage working memory. A significant pre- to post-season increase in fMRI blood oxygen level dependent (BOLD) signal was demonstrated when performing the N-back working memory task in the non-collar group but not in the collar group, despite the comparable exposure to head impacts during the season between the two groups. The collar group demonstrated significantly smaller pre- to post-season change in fMRI BOLD signal than the non-collar group, suggesting a potential protective effect from the collar device. Significant correlations were also found between the pre- to post-season increase in fMRI brain activation and the decrease in task accuracy in the non-collar group, indicating an association between the compensatory mechanism in underlying neurophysiology and the alteration in the behavioral outcomes.

Effort-related functions of nucleus accumbens dopamine and associated forebrain circuits.

PubMed

Salamone, J D; Correa, M; Farrar, A; Mingote, S M

2007-04-01

Over the last several years, it has become apparent that there are critical problems with the hypothesis that brain dopamine (DA) systems, particularly in the nucleus accumbens, directly mediate the rewarding or primary motivational characteristics of natural stimuli such as food. Hypotheses related to DA function are undergoing a substantial restructuring, such that the classic emphasis on hedonia and primary reward is giving way to diverse lines of research that focus on aspects of instrumental learning, reward prediction, incentive motivation, and behavioral activation. The present review discusses dopaminergic involvement in behavioral activation and, in particular, emphasizes the effort-related functions of nucleus accumbens DA and associated forebrain circuitry. The effects of accumbens DA depletions on food-seeking behavior are critically dependent upon the work requirements of the task. Lever pressing schedules that have minimal work requirements are largely unaffected by accumbens DA depletions, whereas reinforcement schedules that have high work (e.g., ratio) requirements are substantially impaired by accumbens DA depletions. Moreover, interference with accumbens DA transmission exerts a powerful influence over effort-related decision making. Rats with accumbens DA depletions reallocate their instrumental behavior away from food-reinforced tasks that have high response requirements, and instead, these rats select a less-effortful type of food-seeking behavior. Along with prefrontal cortex and the amygdala, nucleus accumbens is a component of the brain circuitry regulating effort-related functions. Studies of the brain systems regulating effort-based processes may have implications for understanding drug abuse, as well as energy-related disorders such as psychomotor slowing, fatigue, or anergia in depression.

Simple Linux Utility for Resource Management

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

Jette, M.

2009-09-09

SLURM is an open source, fault-tolerant, and highly scalable cluster management and job scheduling system for large and small computer clusters. As a cluster resource manager, SLURM has three key functions. First, it allocates exclusive and/or non exclusive access to resources (compute nodes) to users for some duration of time so they can perform work. Second, it provides a framework for starting, executing, and monitoring work (normally a parallel job) on the set of allciated nodes. Finally, it arbitrates conflicting requests for resouces by managing a queue of pending work.

Selective Enhancement of Nucleases by Polyvalent DNA-Functionalized Gold Nanoparticles

PubMed Central

Prigodich, Andrew E.; Alhasan, Ali H.

2011-01-01

We demonstrate that polyvalent DNA-functionalized gold nanoparticles (DNA-Au NPs) selectively enhance Ribonuclease H (RNase H) activity, while inhibiting most biologically relevant nucleases. This combination of properties is particularly interesting in the context of gene regulation, since high RNase H activity results in rapid mRNA degradation and general nuclease inhibition results in high biological stability. We investigate the mechanism of selective RNase H activation and find that the high DNA density of DNA-Au NPs is responsible for this unusual behavior. This work adds to our understanding of polyvalent DNA-Au NPs as gene regulation agents, and suggests a new model for selectively controlling protein-nanoparticle interactions. PMID:21268581

Heterozygous deletion of the LRFN2 gene is associated with working memory deficits

PubMed Central

Thevenon, Julien; Souchay, Céline; Seabold, Gail K; Dygai-Cochet, Inna; Callier, Patrick; Gay, Sébastien; Corbin, Lucie; Duplomb, Laurence; Thauvin-Robinet, Christel; Masurel-Paulet, Alice; El Chehadeh, Salima; Avila, Magali; Minot, Delphine; Guedj, Eric; Chancenotte, Sophie; Bonnet, Marlène; Lehalle, Daphne; Wang, Ya-Xian; Kuentz, Paul; Huet, Frédéric; Mosca-Boidron, Anne-Laure; Marle, Nathalie; Petralia, Ronald S; Faivre, Laurence

2016-01-01

Learning disabilities (LDs) are a clinically and genetically heterogeneous group of diseases. Array-CGH and high-throughput sequencing have dramatically expanded the number of genes implicated in isolated intellectual disabilities and LDs, highlighting the implication of neuron-specific post-mitotic transcription factors and synaptic proteins as candidate genes. We report a unique family diagnosed with autosomal dominant learning disability and a 6p21 microdeletion segregating in three patients. The 870 kb microdeletion encompassed the brain-expressed gene LRFN2, which encodes for a synaptic cell adhesion molecule. Neuropsychological assessment identified selective working memory deficits, with borderline intellectual functioning. Further investigations identified a defect in executive function, and auditory-verbal processes. These data were consistent with brain MRI and FDG-PET functional brain imaging, which, when compared with controls, revealed abnormal brain volume and hypometabolism of gray matter structures implicated in working memory. We performed electron microscopy immunogold labeling demonstrating the localization of LRFN2 at synapses of cerebellar and hippocampal rat neurons, often associated with the NR1 subunit of N-methyl-D-aspartate receptors (NMDARs). Altogether, the combined approaches imply a role for LRFN2 in LD, specifically for working memory processes and executive function. In conclusion, the identification of familial cases of clinically homogeneous endophenotypes of LD might help in both the management of patients and genetic counseling for families. PMID:26486473

Exploring the work function variability and structural stability of VO2(1 1 0) surface upon noble metal (Ag, Au, Pt) adsorption and incorporation

NASA Astrophysics Data System (ADS)

Chen, Lanli; Cui, Yuanyuan; Shi, Siqi; Luo, Hongjie; Gao, Yanfeng

2018-08-01

Vanadium dioxide (VO2) has attracted great attention, with scientific and technological advances over the past few decades due to its reversible metal-insulator transition at 340 K. However, the high phase transition temperature (Tc) of VO2 limits its practical applications. Our first-principles calculations show that VO2(1 1 0) surfaces with adsorbed noble metals (Ag, Au, Pt) exhibit a lower work function compared with the clean surface and further induces a lower Tc due to charge transfer from the noble metals to the VO2(1 1 0) surface. However, the work functions of the VO2(1 1 0) surfaces after the incorporation of noble metals are higher than that of the clean surface. In addition, the results of formation energies of various configurations show that the VO2(1 1 0) surface with the adsorption and incorporation of Ag is energetically more favorable than those with Au and Pt. Therefore, it may be concluded that the adsorption and incorporation of noble metals can not only tailor the work function of VO2, in turn realizing the rational tuning of Tc of VO2, but also stabilize the structures of VO2 thin films. These results provide guidance for further exploration of VO2-based optical switching devices and smart windows.

Work function variation of MoS{sub 2} atomic layers grown with chemical vapor deposition: The effects of thickness and the adsorption of water/oxygen molecules

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

Kim, Jong Hun; Kim, Jae Hyeon; Park, Jeong Young, E-mail: peterlee@skku.edu, E-mail: jeongypark@kaist.ac.kr

2015-06-22

The electrical properties of two-dimensional atomic sheets exhibit remarkable dependences on layer thickness and surface chemistry. Here, we investigated the variation of the work function properties of MoS{sub 2} films prepared with chemical vapor deposition (CVD) on SiO{sub 2} substrates with the number of film layers. Wafer-scale CVD MoS{sub 2} films with 2, 4, and 12 layers were fabricated on SiO{sub 2}, and their properties were evaluated by using Raman and photoluminescence spectroscopies. In accordance with our X-ray photoelectron spectroscopy results, our Kelvin probe force microscopy investigation found that the surface potential of the MoS{sub 2} films increases by ∼0.15 eVmore » when the number of layers is increased from 2 to 12. Photoemission spectroscopy (PES) with in-situ annealing under ultra high vacuum conditions was used to directly demonstrate that this work function shift is associated with the screening effects of oxygen or water molecules adsorbed on the film surface. After annealing, it was found with PES that the surface potential decreases by ∼0.2 eV upon the removal of the adsorbed layers, which confirms that adsorbed species have a role in the variation in the work function.« less

Reliability, synchrony and noise

PubMed Central

Ermentrout, G. Bard; Galán, Roberto F.; Urban, Nathaniel N.

2008-01-01

The brain is noisy. Neurons receive tens of thousands of highly fluctuating inputs and generate spike trains that appear highly irregular. Much of this activity is spontaneous—uncoupled to overt stimuli or motor outputs—leading to questions about the functional impact of this noise. Although noise is most often thought of as disrupting patterned activity and interfering with the encoding of stimuli, recent theoretical and experimental work has shown that noise can play a constructive role—leading to increased reliability or regularity of neuronal firing in single neurons and across populations. These results raise fundamental questions about how noise can influence neural function and computation. PMID:18603311

Water/alcohol soluble conjugated polymers as highly efficient electron transporting/injection layer in optoelectronic devices.

PubMed

Huang, Fei; Wu, Hongbin; Cao, Yong

2010-07-01

Water/alcohol soluble conjugated polymers (WSCPs) can be processed from water or other polar solvents, which offer good opportunities to avoid interfacial mixing upon fabrication of multilayer polymer optoelectronic devices by solution processing, and can dramatically improve charge injection from high work-function metal cathode resulting in greatly enhancement of the device performance. In this critical review, the authors provide a brief review of recent developments in this field, including the materials design, functional principles, and their unique applications as interface modification layer in solution-processable multilayer optoelectronic devices (135 references).

High performance ZnO:Al films deposited on PET substrates using facing target sputtering

NASA Astrophysics Data System (ADS)

Guo, Tingting; Dong, Guobo; Gao, Fangyuan; Xiao, Yu; Chen, Qiang; Diao, Xungang

2013-10-01

ZnO:Al (ZAO) thin films have been deposited on flexible PET substrates using a plasma damage-free facing target sputtering system at room temperature. The structure, surface morphology, electrical and optical properties were investigated as a function of working power. All the samples have a highly preferred orientation of the c-axis perpendicular to the PET substrate and have a high quality surface. With increased working power, the carrier concentration changes slightly, the mobility increases at the beginning and decreases after it reaches a maximum value, in line with electrical conductivity. The figure of merit has been significantly improved with increasing of the working power. Under the optimized condition, the lowest resistivity of 1.3 × 10-3 Ω cm with a sheet resistance of 29 Ω/□ and the relative visible transmittance above 93% in the visible region were obtained.

Symmetry Energy Effects in the Neutron Star Properties

NASA Astrophysics Data System (ADS)

Alvarez-Castillo, D. E.; Kubis, S.

2012-12-01

The functional form of the nuclear symmetry energy has only been determined in a very narrow range of densities. Uncertainties concern both the low as well as the high density behaviour of this function. In this work different shapes of the symmetry energy, consistent with the experimental data, were introduced and their consequences for the crustal properties of neutron stars are presented. The resulting models are in agreement with astrophysical observations.

High-resolution (>5 800 time-bandwidth product) shear mode TeO2 deflector

NASA Astrophysics Data System (ADS)

Soos, Jolanta I.; Caviris, Nicholas P.; Phuvan, Sonlinh

1992-12-01

Acousto-optic deflectors play an important role in optical signal processing systems due to their real time processing capabilities, as well as their conversion capabilities of a function of time to a function of space and time. In this work Brimrose investigated the design and fabrication of state-of-the-art, very large time-bandwidth acousto-optic devices from TeO2 single crystals.

Discovering functional interdependence relationship in PPI networks for protein complex identification.

PubMed

Lam, Winnie W M; Chan, Keith C C

2012-04-01

Protein molecules interact with each other in protein complexes to perform many vital functions, and different computational techniques have been developed to identify protein complexes in protein-protein interaction (PPI) networks. These techniques are developed to search for subgraphs of high connectivity in PPI networks under the assumption that the proteins in a protein complex are highly interconnected. While these techniques have been shown to be quite effective, it is also possible that the matching rate between the protein complexes they discover and those that are previously determined experimentally be relatively low and the "false-alarm" rate can be relatively high. This is especially the case when the assumption of proteins in protein complexes being more highly interconnected be relatively invalid. To increase the matching rate and reduce the false-alarm rate, we have developed a technique that can work effectively without having to make this assumption. The name of the technique called protein complex identification by discovering functional interdependence (PCIFI) searches for protein complexes in PPI networks by taking into consideration both the functional interdependence relationship between protein molecules and the network topology of the network. The PCIFI works in several steps. The first step is to construct a multiple-function protein network graph by labeling each vertex with one or more of the molecular functions it performs. The second step is to filter out protein interactions between protein pairs that are not functionally interdependent of each other in the statistical sense. The third step is to make use of an information-theoretic measure to determine the strength of the functional interdependence between all remaining interacting protein pairs. Finally, the last step is to try to form protein complexes based on the measure of the strength of functional interdependence and the connectivity between proteins. For performance evaluation, PCIFI was used to identify protein complexes in real PPI network data and the protein complexes it found were matched against those that were previously known in MIPS. The results show that PCIFI can be an effective technique for the identification of protein complexes. The protein complexes it found can match more known protein complexes with a smaller false-alarm rate and can provide useful insights into the understanding of the functional interdependence relationships between proteins in protein complexes.

The Development of Metaphor Comprehension and Its Relationship with Relational Verbal Reasoning and Executive Function

PubMed Central

Montoro, Pedro R.; Herrero, Laura; Ballestrino, Patricia; Sebastián, Iraia

2016-01-01

Our main objective was to analyse the different contributions of relational verbal reasoning (analogical and class inclusion) and executive functioning to metaphor comprehension across development. We postulated that both relational reasoning and executive functioning should predict individual and developmental differences. However, executive functioning would become increasingly involved when metaphor comprehension is highly demanding, either because of the metaphors’ high difficulty (relatively novel metaphors in the absence of a context) or because of the individual’s special processing difficulties, such as low levels of reading experience or low semantic knowledge. Three groups of participants, 11-year-olds, 15-year-olds and young adults, were assessed in different relational verbal reasoning tasks—analogical and class-inclusion—and in executive functioning tasks—updating information in working memory, inhibition, and shifting. The results revealed clear progress in metaphor comprehension between ages 11 and 15 and between ages 15 and 21. However, the importance of executive function in metaphor comprehension was evident by age 15 and was restricted to updating information in working memory and cognitive inhibition. Participants seemed to use two different strategies to interpret metaphors: relational verbal reasoning and executive functioning. This was clearly shown when comparing the performance of the "more efficient" participants in metaphor interpretation with that of the "less efficient” ones. Whereas in the first case none of the executive variables or those associated with relational verbal reasoning were significantly related to metaphor comprehension, in the latter case, both groups of variables had a clear predictor effect. PMID:26954501

SiSSR: Simultaneous subdivision surface registration for the quantification of cardiac function from computed tomography in canines.

PubMed

Vigneault, Davis M; Pourmorteza, Amir; Thomas, Marvin L; Bluemke, David A; Noble, J Alison

2018-05-01

Recent improvements in cardiac computed tomography (CCT) allow for whole-heart functional studies to be acquired at low radiation dose (<2mSv) and high-temporal resolution (<100ms) in a single heart beat. Although the extraction of regional functional information from these images is of great clinical interest, there is a paucity of research into the quantification of regional function from CCT, contrasting with the large body of work in echocardiography and cardiac MR. Here we present the Simultaneous Subdivision Surface Registration (SiSSR) method: a fast, semi-automated image analysis pipeline for quantifying regional function from contrast-enhanced CCT. For each of thirteen adult male canines, we construct an anatomical reference mesh representing the left ventricular (LV) endocardium, obviating the need for a template mesh to be manually sculpted and initialized. We treat this generated mesh as a Loop subdivision surface, and adapt a technique previously described in the context of 3-D echocardiography to register these surfaces to the endocardium efficiently across all cardiac frames simultaneously. Although previous work performs the registration at a single resolution, we observe that subdivision surfaces naturally suggest a multiresolution approach, leading to faster convergence and avoiding local minima. We additionally make two notable changes to the cost function of the optimization, explicitly encouraging plausible biological motion and high mesh quality. Finally, we calculate an accepted functional metric for CCT from the registered surfaces, and compare our results to an alternate state-of-the-art CCT method. Published by Elsevier B.V.

New classes of piezoelectrics, ferroelectrics, and antiferroelectrics by first-principles high-throughput materials design

NASA Astrophysics Data System (ADS)

Bennett, Joseph

2013-03-01

Functional materials, such as piezoelectrics, ferroelectrics, and antiferroelectrics, exhibit large changes with applied fields and stresses. This behavior enables their incorporation into a wide variety of devices in technological fields such as energy conversion/storage and information processing/storage. Discovery of functional materials with improved performance or even new types of responses is thus not only a scientific challenge, but can have major impacts on society. In this talk I will review our efforts to uncover new families of functional materials using a combined crystallographic database/high-throughput first-principles approach. I will describe our work on the design and discovery of thousands of new functional materials, specifically the LiAlSi family as piezoelectrics, the LiGaGe family as ferroelectrics, and the MgSrSi family as antiferroelectrics.

Variance-based interaction index measuring heteroscedasticity

NASA Astrophysics Data System (ADS)

Ito, Keiichi; Couckuyt, Ivo; Poles, Silvia; Dhaene, Tom

2016-06-01

This work is motivated by the need to deal with models with high-dimensional input spaces of real variables. One way to tackle high-dimensional problems is to identify interaction or non-interaction among input parameters. We propose a new variance-based sensitivity interaction index that can detect and quantify interactions among the input variables of mathematical functions and computer simulations. The computation is very similar to first-order sensitivity indices by Sobol'. The proposed interaction index can quantify the relative importance of input variables in interaction. Furthermore, detection of non-interaction for screening can be done with as low as 4 n + 2 function evaluations, where n is the number of input variables. Using the interaction indices based on heteroscedasticity, the original function may be decomposed into a set of lower dimensional functions which may then be analyzed separately.

Impact of lifestyle dimensions on brain pathology and cognition

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

Schreiber, Stefanie; Vogel, Jacob; Schwimmer, Henry D.

Single lifestyle factors affect brain biomarkers and cognition. Here in this work, we addressed the covariance of various lifestyle elements and investigated their impact on positron emission tomography-based β-amyloid (Aβ), hippocampal volume, and cognitive function in aged controls. Lower Aβ burden was associated with a lifestyle comprising high cognitive engagement and low vascular risk, particularly in apolipoprotein E ε4 carriers. Although cognitive function was related to high lifetime cognitive engagement and low vascular risk, Aβ load had no relation to current cognitive function. The covariance between high adult socioeconomic status, high education, and low smoking prevalence predicted better cognitive functionmore » and this was mediated by larger hippocampal volume. Our data show that lifestyle is a complex construct composed of associated variables, some of which reflect factors operating over the life span and others which may be developmental. These factors affect brain health via different pathways, which may reinforce one another. Finally, our findings moreover support the importance of an intellectually enriched lifestyle accompanied by vascular health on both cognition and presumed cerebral mediators of cognitive function.« less

Impact of lifestyle dimensions on brain pathology and cognition

DOE PAGES

Schreiber, Stefanie; Vogel, Jacob; Schwimmer, Henry D.; ...

2016-01-30

Single lifestyle factors affect brain biomarkers and cognition. Here in this work, we addressed the covariance of various lifestyle elements and investigated their impact on positron emission tomography-based β-amyloid (Aβ), hippocampal volume, and cognitive function in aged controls. Lower Aβ burden was associated with a lifestyle comprising high cognitive engagement and low vascular risk, particularly in apolipoprotein E ε4 carriers. Although cognitive function was related to high lifetime cognitive engagement and low vascular risk, Aβ load had no relation to current cognitive function. The covariance between high adult socioeconomic status, high education, and low smoking prevalence predicted better cognitive functionmore » and this was mediated by larger hippocampal volume. Our data show that lifestyle is a complex construct composed of associated variables, some of which reflect factors operating over the life span and others which may be developmental. These factors affect brain health via different pathways, which may reinforce one another. Finally, our findings moreover support the importance of an intellectually enriched lifestyle accompanied by vascular health on both cognition and presumed cerebral mediators of cognitive function.« less

Programming Cell Adhesion for On-Chip Sequential Boolean Logic Functions.

PubMed

Qu, Xiangmeng; Wang, Shaopeng; Ge, Zhilei; Wang, Jianbang; Yao, Guangbao; Li, Jiang; Zuo, Xiaolei; Shi, Jiye; Song, Shiping; Wang, Lihua; Li, Li; Pei, Hao; Fan, Chunhai

2017-08-02

Programmable remodelling of cell surfaces enables high-precision regulation of cell behavior. In this work, we developed in vitro constructed DNA-based chemical reaction networks (CRNs) to program on-chip cell adhesion. We found that the RGD-functionalized DNA CRNs are entirely noninvasive when interfaced with the fluidic mosaic membrane of living cells. DNA toehold with different lengths could tunably alter the release kinetics of cells, which shows rapid release in minutes with the use of a 6-base toehold. We further demonstrated the realization of Boolean logic functions by using DNA strand displacement reactions, which include multi-input and sequential cell logic gates (AND, OR, XOR, and AND-OR). This study provides a highly generic tool for self-organization of biological systems.

Compact Embedded Wireless Sensor-Based Monitoring of Concrete Curing.

PubMed

Cabezas, Joaquín; Sánchez-Rodríguez, Trinidad; Gómez-Galán, Juan Antonio; Cifuentes, Héctor; González Carvajal, Ramón

2018-03-15

This work presents the design, construction and testing of a new embedded sensor system for monitoring concrete curing. A specific mote has been implemented to withstand the aggressive environment without affecting the measured variables. The system also includes a real-time monitoring application operating from a remote computer placed in a central location. The testing was done in two phases: the first in the laboratory, to validate the functional requirements of the developed devices; and the second on civil works to evaluate the functional features of the devices, such as range, robustness and flexibility. The devices were successfully implemented resulting in a low cost, highly reliable, compact and non-destructive solution.

Compact Embedded Wireless Sensor-Based Monitoring of Concrete Curing

PubMed Central

Cabezas, Joaquín; Sánchez-Rodríguez, Trinidad; González Carvajal, Ramón

2018-01-01

This work presents the design, construction and testing of a new embedded sensor system for monitoring concrete curing. A specific mote has been implemented to withstand the aggressive environment without affecting the measured variables. The system also includes a real-time monitoring application operating from a remote computer placed in a central location. The testing was done in two phases: the first in the laboratory, to validate the functional requirements of the developed devices; and the second on civil works to evaluate the functional features of the devices, such as range, robustness and flexibility. The devices were successfully implemented resulting in a low cost, highly reliable, compact and non-destructive solution. PMID:29543765

Electrokinetic pump

DOEpatents

Patel, Kamlesh D.

2007-11-20

A method for altering the surface properties of a particle bed. In application, the method pertains particularly to an electrokinetic pump configuration where nanoparticles are bonded to the surface of the stationary phase to alter the surface properties of the stationary phase including the surface area and/or the zeta potential and thus improve the efficiency and operating range of these pumps. By functionalizing the nanoparticles to change the zeta potential the electrokinetic pump is rendered capable of operating with working fluids having pH values that can range from 2-10 generally and acidic working fluids in particular. For applications in which the pump is intended to handle highly acidic solutions latex nanoparticles that are quaternary amine functionalized can be used.

Presenteeism, stress resilience, and physical activity in older manual workers: a person-centred analysis.

PubMed

Thogersen-Ntoumani, Cecilie; Black, Julie; Lindwall, Magnus; Whittaker, Anna; Balanos, George M

2017-12-01

This study used a person-centred approach to explore typologies of older manual workers based on presenteeism, stress resilience, and physical activity. Older manual workers ( n  = 217; 69.1% male; age range 50-77; M age = 57.11 years; SD = 5.62) from a range of UK-based organisations, representing different manual job roles, took part in the study. A cross-sectional survey design was used. Based on the three input variables: presenteeism, stress resilience and physical activity, four distinct profiles were identified on using Latent Profile Analysis. One group ('High sport/exercise and well-functioning'; 5.50%) engaged in high levels of sport/exercise and exhibited low levels of stress resilience and all types of presenteeism. Another profile ('Physically burdened'; 9.70%) reported high levels of work and leisure-time physical activity, low stress resilience, as well as high levels of presenteeism due to physical and time demands. A 'Moderately active and functioning' group (46.50%) exhibited moderate levels on all variables. Finally, the fourth profile ('Moderately active with high presenteeism'; 38.20%) reported engaging in moderate levels of physical activity and had relatively high levels of stress resilience, yet also high levels of presenteeism. The profiles differed on work affect and health perceptions largely in the expected directions. There were no differences between the profiles in socio-demographics. These results highlight complex within-person interactions between presenteeism, stress resilience, and physical activity in older manual workers. The identification of profiles of older manual workers who are at risk of poor health and functioning may inform targeted interventions to help retain them in the workforce for longer.

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

PubMed

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

2015-10-01

This study aims to (i) assess work functioning in employees returning to work with a major depression in remission, (ii) study the predictors of impaired work functioning. Participants diagnosed with major depressive disorder (MDD), on long term sick leave (mean 27 weeks) and treated in a specialized mental healthcare setting, were selected from an intervention study sample. They were eligible for this study if they were remitted from their depression and had returned to work for at least 50% of their contract hours at 18 month follow-up. Work functioning was assessed with the Work Limitations Questionnaire (WLQ) and the Need For Recovery scale (NFR). Potential predictors of impaired work functioning were demographic characteristics (assessed at baseline), health characteristics (assessed at baseline, six and twelve month follow-up), and personality- and work characteristics (assessed at 18 month follow-up). After their return to work with MDD in remission, employees were on average still impaired in their work functioning. Personality characteristics were the strongest predictor of this impaired work functioning, followed by health and work characteristics. In the final prediction model, only a passive reaction coping style remained as predictor. We used self-report data with respect to work functioning and work characteristics and not an assessment by a supervisor. Personality trait, coping style, and ability to manage the work environment should be addressed in mental health and return-to-work interventions. Subsequent improved work functioning may be beneficial for mental health and may reduce societal costs. Copyright © 2015 Elsevier B.V. All rights reserved.

JPRS Report, Science & Technology, Europe & Latin America

DTIC Science & Technology

1987-07-23

one test was done at the CERN, jointly with a number of Western European countries in an international high energy ...satellite remains in its orbit and functions flawlessly. We have received recognition from ESA in this as a significant developmental step, as the ... from the OECD has acquainted itself with research work on the technical level in Finland and given it high marks. The

Using High Performance Computing to Examine the Processes of Neurogenesis Underlying Pattern Separation/Completion of Episodic Information.

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

Aimone, James Bradley; Betty, Rita

Using High Performance Computing to Examine the Processes of Neurogenesis Underlying Pattern Separation/Completion of Episodic Information - Sandia researchers developed novel methods and metrics for studying the computational function of neurogenesis, thus generating substantial impact to the neuroscience and neural computing communities. This work could benefit applications in machine learning and other analysis activities.

Reproducibility in Natural Language Processing: A Case Study of Two R Libraries for Mining PubMed/MEDLINE

PubMed Central

Cohen, K. Bretonnel; Xia, Jingbo; Roeder, Christophe; Hunter, Lawrence E.

2018-01-01

There is currently a crisis in science related to highly publicized failures to reproduce large numbers of published studies. The current work proposes, by way of case studies, a methodology for moving the study of reproducibility in computational work to a full stage beyond that of earlier work. Specifically, it presents a case study in attempting to reproduce the reports of two R libraries for doing text mining of the PubMed/MEDLINE repository of scientific publications. The main findings are that a rational paradigm for reproduction of natural language processing papers can be established; the advertised functionality was difficult, but not impossible, to reproduce; and reproducibility studies can produce additional insights into the functioning of the published system. Additionally, the work on reproducibility lead to the production of novel user-centered documentation that has been accessed 260 times since its publication—an average of once a day per library. PMID:29568821

Job shop scheduling problem with late work criterion

NASA Astrophysics Data System (ADS)

Piroozfard, Hamed; Wong, Kuan Yew

2015-05-01

Scheduling is considered as a key task in many industries, such as project based scheduling, crew scheduling, flight scheduling, machine scheduling, etc. In the machine scheduling area, the job shop scheduling problems are considered to be important and highly complex, in which they are characterized as NP-hard. The job shop scheduling problems with late work criterion and non-preemptive jobs are addressed in this paper. Late work criterion is a fairly new objective function. It is a qualitative measure and concerns with late parts of the jobs, unlike classical objective functions that are quantitative measures. In this work, simulated annealing was presented to solve the scheduling problem. In addition, operation based representation was used to encode the solution, and a neighbourhood search structure was employed to search for the new solutions. The case studies are Lawrence instances that were taken from the Operations Research Library. Computational results of this probabilistic meta-heuristic algorithm were compared with a conventional genetic algorithm, and a conclusion was made based on the algorithm and problem.

The High Strain Rate Deformation Behavior of High Purity Magnesium and AZ31B Magnesium Alloy

NASA Astrophysics Data System (ADS)

Livescu, Veronica; Cady, Carl M.; Cerreta, Ellen K.; Henrie, Benjamin L.; Gray, George T.

The deformation in compression of pure magnesium and AZ31B magnesium alloy, both with a strong basal pole texture, has been investigated as a function of temperature, strain rate, and specimen orientation. The mechanical response of both metals is highly dependent upon the orientation of loading direction with respect to the basal pole. Specimens compressed along the basal pole direction have a high sensitivity to strain rate and temperature and display a concave down work hardening behavior. Specimens loaded perpendicularly to the basal pole have a yield stress that is relatively insensitive to strain rate and temperature and a work hardening behavior that is parabolic and then linearly upwards. Both specimen orientations display a mechanical response that is sensitive to temperature and strain rate. Post mortem characterization of the pure magnesium was conducted on a subset of specimens to determine the microstructural and textural evolution during deformation and these results are correlated with the observed work hardening behavior and strain rate sensitivities were calculated.

Comprehensive Study of Lanthanum Aluminate High-Dielectric-Constant Gate Oxides for AdvancedCMOS Devices

PubMed Central

Suzuki, Masamichi

2012-01-01

A comprehensive study of the electrical and physical characteristics of Lanthanum Aluminate (LaAlO3) high-dielectric-constant gate oxides for advanced CMOS devices was performed. The most distinctive feature of LaAlO3 as compared with Hf-based high-k materials is the thermal stability at the interface with Si, which suppresses the formation of a low-permittivity Si oxide interfacial layer. Careful selection of the film deposition conditions has enabled successful deposition of an LaAlO3 gate dielectric film with an equivalent oxide thickness (EOT) of 0.31 nm. Direct contact with Si has been revealed to cause significant tensile strain to the Si in the interface region. The high stability of the effective work function with respect to the annealing conditions has been demonstrated through comparison with Hf-based dielectrics. It has also been shown that the effective work function can be tuned over a wide range by controlling the La/(La + Al) atomic ratio. In addition, gate-first n-MOSFETs with ultrathin EOT that use sulfur-implanted Schottky source/drain technology have been fabricated using a low-temperature process. PMID:28817057

Managing a Modern University Research Center.

ERIC Educational Resources Information Center

Veres, John G., III

1988-01-01

The university research center of the future will function best to serve the rapidly changing public and private demand for services with a highly trained core staff, adequately funded and equipped, whose morale and quality of work performance is a prime consideration. (MSE)

Working memory and executive functions: effects of training on academic achievement.

PubMed

Titz, Cora; Karbach, Julia

2014-11-01

The aim of this review is to illustrate the role of working memory and executive functions for scholastic achievement as an introduction to the question of whether and how working memory and executive control training may improve academic abilities. The review of current research showed limited but converging evidence for positive effects of process-based complex working-memory training on academic abilities, particularly in the domain of reading. These benefits occurred in children suffering from cognitive and academic deficits as well as in healthy students. Transfer of training to mathematical abilities seemed to be very limited and to depend on the training regime and the characteristics of the study sample. A core issue in training research is whether high- or low-achieving children benefit more from cognitive training. Individual differences in terms of training-related benefits suggested that process-based working memory and executive control training often induced compensation effects with larger benefits in low performing individuals. Finally, we discuss the effects of process-based training in relation to other types of interventions aimed at improving academic achievement.

High-speed and high-fidelity system and method for collecting network traffic

DOEpatents

Weigle, Eric H [Los Alamos, NM

2010-08-24

A system is provided for the high-speed and high-fidelity collection of network traffic. The system can collect traffic at gigabit-per-second (Gbps) speeds, scale to terabit-per-second (Tbps) speeds, and support additional functions such as real-time network intrusion detection. The present system uses a dedicated operating system for traffic collection to maximize efficiency, scalability, and performance. A scalable infrastructure and apparatus for the present system is provided by splitting the work performed on one host onto multiple hosts. The present system simultaneously addresses the issues of scalability, performance, cost, and adaptability with respect to network monitoring, collection, and other network tasks. In addition to high-speed and high-fidelity network collection, the present system provides a flexible infrastructure to perform virtually any function at high speeds such as real-time network intrusion detection and wide-area network emulation for research purposes.

Simulation of electron energy loss spectra of nanomaterials with linear-scaling density functional theory

DOE PAGES

Tait, E. W.; Ratcliff, L. E.; Payne, M. C.; ...

2016-04-20

Experimental techniques for electron energy loss spectroscopy (EELS) combine high energy resolution with high spatial resolution. They are therefore powerful tools for investigating the local electronic structure of complex systems such as nanostructures, interfaces and even individual defects. Interpretation of experimental electron energy loss spectra is often challenging and can require theoretical modelling of candidate structures, which themselves may be large and complex, beyond the capabilities of traditional cubic-scaling density functional theory. In this work, we present functionality to compute electron energy loss spectra within the onetep linear-scaling density functional theory code. We first demonstrate that simulated spectra agree withmore » those computed using conventional plane wave pseudopotential methods to a high degree of precision. The ability of onetep to tackle large problems is then exploited to investigate convergence of spectra with respect to supercell size. As a result, we apply the novel functionality to a study of the electron energy loss spectra of defects on the (1 0 1) surface of an anatase slab and determine concentrations of defects which might be experimentally detectable.« less

Meta-analysis of neuropsychological measures of executive functioning in children and adolescents with high-functioning autism spectrum disorder.

PubMed

Lai, Chun Lun Eric; Lau, Zoe; Lui, Simon S Y; Lok, Eugenia; Tam, Venus; Chan, Quinney; Cheng, Koi Man; Lam, Siu Man; Cheung, Eric F C

2017-05-01

Existing literature on the profile of executive dysfunction in autism spectrum disorder showed inconsistent results. Age, comorbid attention-deficit/hyperactivity disorder (ADHD) and cognitive abilities appeared to play a role in confounding the picture. Previous meta-analyses have focused on a few components of executive functions. This meta-analysis attempted to delineate the profile of deficit in several components of executive functioning in children and adolescents with high-functioning autism spectrum disorder (HFASD). Ninety-eight English published case-control studies comparing children and adolescents with HFASD with typically developing controls using well-known neuropsychological measures to assess executive functions were included. Results showed that children and adolescents with HFASD were moderately impaired in verbal working memory (g = 0.67), spatial working memory (g = 0.58), flexibility (g = 0.59), planning (g = 0.62), and generativity (g = 0.60) except for inhibition (g = 0.41). Subgroup analysis showed that impairments were still significant for flexibility (g = 0.57-0.61), generativity (g = 0.52-0.68), and working memory (g = 0.49-0.56) in a sample of autism spectrum disorder (ASD) subjects without comorbid ADHD or when the cognitive abilities of the ASD group and the control group were comparable. This meta-analysis confirmed the presence of executive dysfunction in children and adolescents with HFASD. These deficits are not solely accounted for by the effect of comorbid ADHD and the general cognitive abilities. Our results support the executive dysfunction hypothesis and contribute to the clinical understanding and possible development of interventions to alleviate these deficits in children and adolescents with HFASD. Autism Res 2017, 10: 911-939. © 2016 International Society for Autism Research, Wiley Periodicals, Inc. © 2016 International Society for Autism Research, Wiley Periodicals, Inc.

Working Memory and Reasoning Benefit from Different Modes of Large-scale Brain Dynamics in Healthy Older Adults.

PubMed

Lebedev, Alexander V; Nilsson, Jonna; Lövdén, Martin

2018-07-01

Researchers have proposed that solving complex reasoning problems, a key indicator of fluid intelligence, involves the same cognitive processes as solving working memory tasks. This proposal is supported by an overlap of the functional brain activations associated with the two types of tasks and by high correlations between interindividual differences in performance. We replicated these findings in 53 older participants but also showed that solving reasoning and working memory problems benefits from different configurations of the functional connectome and that this dissimilarity increases with a higher difficulty load. Specifically, superior performance in a typical working memory paradigm ( n-back) was associated with upregulation of modularity (increased between-network segregation), whereas performance in the reasoning task was associated with effective downregulation of modularity. We also showed that working memory training promotes task-invariant increases in modularity. Because superior reasoning performance is associated with downregulation of modular dynamics, training may thus have fostered an inefficient way of solving the reasoning tasks. This could help explain why working memory training does little to promote complex reasoning performance. The study concludes that complex reasoning abilities cannot be reduced to working memory and suggests the need to reconsider the feasibility of using working memory training interventions to attempt to achieve effects that transfer to broader cognition.

Psychometric evaluation of the Work Readiness Questionnaire in schizophrenia.

PubMed

Potkin, Steven G; Bugarski-Kirola, Dragana; Edgar, Chris J; Soliman, Sherif; Le Scouiller, Stephanie; Kunovac, Jelena; Miguel Velasco, Eugenio; Garibaldi, George M

2016-04-01

Unemployment can negatively impact quality of life among patients with schizophrenia. Employment status depends on ability, opportunity, education, and cultural influences. A clinician-rated scale of work readiness, independent of current work status, can be a valuable assessment tool. A series of studies were conducted to create and validate a Work Readiness Questionnaire (WoRQ) for clinicians to assess patient ability to engage in socially useful activity, independent of work availability. Content validity, test-retest and inter-rater reliability, and construct validity were evaluated in three separate studies. Content validity was supported. Cronbach's α was 0.91, in the excellent range. Clinicians endorsed WoRQ concepts, including treatment adherence, physical appearance, social competence, and symptom control. The final readiness decision showed good test-retest reliability and moderate inter-rater reliability. Work readiness was associated with higher function and lower levels of negative symptoms. Low positive and high negative predictive values confirmed the concept validity. The WoRQ has suitable psychometric properties for use in a clinical trial for patients with a broad range of symptom severity. The scale may be applicable to assess therapeutic interventions. It is not intended to assess eligibility for supported work interventions. The WoRQ is suitable for use in schizophrenia clinical trials to assess patient work functional potential.

Fast cholesterol detection using flow injection microfluidic device with functionalized carbon nanotubes based electrochemical sensor.

PubMed

Wisitsoraat, A; Sritongkham, P; Karuwan, C; Phokharatkul, D; Maturos, T; Tuantranont, A

2010-12-15

This work reports a new cholesterol detection scheme using functionalized carbon nanotube (CNT) electrode in a polydimethylsiloxane/glass based flow injection microfluidic chip. CNTs working, silver reference and platinum counter electrode layers were fabricated on the chip by sputtering and low temperature chemical vapor deposition methods. Cholesterol oxidase prepared in polyvinyl alcohol solution was immobilized on CNTs by in-channel flow technique. Cholesterol analysis based on flow injection chronoamperometric measurement was performed in 150-μm-wide and 150-μm-deep microchannels. Fast and sensitive real-time detection was achieved with high throughput of more than 60 samples per hour and small sample volume of 15 μl. The cholesterol sensor had a linear detection range between 50 and 400 mg/dl. In addition, low cross-sensitivities toward glucose, ascorbic acid, acetaminophen and uric acid were confirmed. The proposed system is promising for clinical diagnostics of cholesterol with high speed real-time detection capability, very low sample consumption, high sensitivity, low interference and good stability. Copyright © 2010 Elsevier B.V. All rights reserved.

Functional specificity for high-level linguistic processing in the human brain.

PubMed

Fedorenko, Evelina; Behr, Michael K; Kanwisher, Nancy

2011-09-27

Neuroscientists have debated for centuries whether some regions of the human brain are selectively engaged in specific high-level mental functions or whether, instead, cognition is implemented in multifunctional brain regions. For the critical case of language, conflicting answers arise from the neuropsychological literature, which features striking dissociations between deficits in linguistic and nonlinguistic abilities, vs. the neuroimaging literature, which has argued for overlap between activations for linguistic and nonlinguistic processes, including arithmetic, domain general abilities like cognitive control, and music. Here, we use functional MRI to define classic language regions functionally in each subject individually and then examine the response of these regions to the nonlinguistic functions most commonly argued to engage these regions: arithmetic, working memory, cognitive control, and music. We find little or no response in language regions to these nonlinguistic functions. These data support a clear distinction between language and other cognitive processes, resolving the prior conflict between the neuropsychological and neuroimaging literatures.

Amorphous transparent conducting oxides in context: Work function survey, trends, and facile modification

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

Yeh, T. C.; Zhu, Q.; Buchholz, D. B.

2015-03-01

The work functions of various amorphous and crystalline transparent conducting oxides (TCO5) were measured using Kelvin probe. The films, made by pulsed laser deposition, exhibited varying work functions dependent on the composition and deposition parameters. Tin oxide showed the largest work functions of the oxides measured, while zinc oxide showed the lowest. Binary and ternary combinations of the basis TCOs showed intermediate work functions dependent on the endpoint components. Amorphous TCO5, important in OPV and other technological applications, exhibited similar work functions to their crystalline counterparts. UV/ozone treatment of TCOs temporarily increased the work function, consistent with proposed defect mechanismsmore » associated with near-surface changes in carrier content and Fermi level. Finally, a method for facile adjustment of the work function of commercial TCOs by atomic layer deposition (ALD) capping layers was presented, illustrated by the growth of zinc oxide layers on commercial crystalline ITO films.« less

Amorphous transparent conducting oxides in context: Work function survey, trends, and facile modification

NASA Astrophysics Data System (ADS)

Yeh, T. C.; Zhu, Q.; Buchholz, D. B.; Martinson, A. B.; Chang, R. P. H.; Mason, T. O.

2015-03-01

The work functions of various amorphous and crystalline transparent conducting oxides (TCOs) were measured using Kelvin probe. The films, made by pulsed laser deposition, exhibited varying work functions dependent on the composition and deposition parameters. Tin oxide showed the largest work functions of the oxides measured, while zinc oxide showed the lowest. Binary and ternary combinations of the basis TCOs showed intermediate work functions dependent on the endpoint components. Amorphous TCOs, important in OPV and other technological applications, exhibited similar work functions to their crystalline counterparts. UV/ozone treatment of TCOs temporarily increased the work function, consistent with proposed defect mechanisms associated with near-surface changes in carrier content and Fermi level. Finally, a method for facile adjustment of the work function of commercial TCOs by atomic layer deposition (ALD) capping layers was presented, illustrated by the growth of zinc oxide layers on commercial crystalline ITO films.

Dynamic reconfiguration of human brain functional networks through neurofeedback.

PubMed

Haller, Sven; Kopel, Rotem; Jhooti, Permi; Haas, Tanja; Scharnowski, Frank; Lovblad, Karl-Olof; Scheffler, Klaus; Van De Ville, Dimitri

2013-11-01

Recent fMRI studies demonstrated that functional connectivity is altered following cognitive tasks (e.g., learning) or due to various neurological disorders. We tested whether real-time fMRI-based neurofeedback can be a tool to voluntarily reconfigure brain network interactions. To disentangle learning-related from regulation-related effects, we first trained participants to voluntarily regulate activity in the auditory cortex (training phase) and subsequently asked participants to exert learned voluntary self-regulation in the absence of feedback (transfer phase without learning). Using independent component analysis (ICA), we found network reconfigurations (increases in functional network connectivity) during the neurofeedback training phase between the auditory target region and (1) the auditory pathway; (2) visual regions related to visual feedback processing; (3) insula related to introspection and self-regulation and (4) working memory and high-level visual attention areas related to cognitive effort. Interestingly, the auditory target region was identified as the hub of the reconfigured functional networks without a-priori assumptions. During the transfer phase, we again found specific functional connectivity reconfiguration between auditory and attention network confirming the specific effect of self-regulation on functional connectivity. Functional connectivity to working memory related networks was no longer altered consistent with the absent demand on working memory. We demonstrate that neurofeedback learning is mediated by widespread changes in functional connectivity. In contrast, applying learned self-regulation involves more limited and specific network changes in an auditory setup intended as a model for tinnitus. Hence, neurofeedback training might be used to promote recovery from neurological disorders that are linked to abnormal patterns of brain connectivity. Copyright © 2013 Elsevier Inc. All rights reserved.

Medically unexplained physical symptoms and work functioning over 2 years: their association and the influence of depressive and anxiety disorders and job characteristics.

PubMed

den Boeft, Madelon; Twisk, Jos W R; Hoekstra, Trynke; Terluin, Berend; Penninx, Brenda W J H; van der Wouden, Johannes C; Numans, Mattijs E; van der Horst, Henriette E

2016-04-14

Medically unexplained physical symptoms (MUPS) are highly prevalent and may affect work functioning. In this study we aimed to assess the longitudinal association between MUPS and work functioning over 2 years and the influence of job characteristics and depressive and anxiety disorders on this association. We assessed the longitudinal association between MUPS and work functioning, operationalized in terms of absenteeism and disability at work, in 1887 working participants from the Netherlands Study of Depression and Anxiety (NESDA). The NESDA study population included participants with a current depressive and/or anxiety disorder, participants with a lifetime risk and/or subthreshold symptoms and healthy controls. Absenteeism was assessed with the Health and Labour Questionnaire Short Form and disability with the World Health Organization Disability Assessment Schedule II. MUPS were measured with the Four Dimensional Symptom Questionnaire. Measurements were taken at baseline and at 2 years follow-up. We used mixed model analyses to correct for the dependency of observations within participants. MUPS were positively associated with disability (regression coefficient 0.304; 95% CI 0.281-0.327) and with short and long-term absenteeism over 2 years (OR 1.030, 95% CI 1.016-1.045; OR 1.099, 95% CI 1.085-1.114). After adjusting for depressive disorders, anxiety disorders and job characteristics, associations weakened but remained significant. Our results show that MUPS were positively associated with disability and absenteeism over 2 years, even after adjusting for depressive and anxiety disorders and job characteristics. This suggests that early identification of MUPS and adequate management is important.

Which components of health information technology will drive financial value?

PubMed

Kern, Lisa M; Wilcox, Adam; Shapiro, Jason; Dhopeshwarkar, Rina V; Kaushal, Rainu

2012-08-01

The financial effects of electronic health records (EHRs) and health information exchange (HIE) are largely unknown, despite unprecedented federal incentives for their use. We sought to understand which components of EHRs and HIE are most likely to drive financial savings in the ambulatory, inpatient, and emergency department settings. Framework development and a national expert panel. We searched the literature to identify functionalities enabled by EHRs and HIE across the 3 healthcare settings. We rated each of 233 functionality-setting combinations on their likelihood of having a positive financial effect. We validated the top-scoring functionalities with a panel of 28 national experts, and we compared the high-scoring functionalities with Stage 1 meaningful use criteria. We identified 54 high-scoring functionality- setting combinations, 27 for EHRs and 27 for HIE. Examples of high-scoring functionalities included providing alerts for expensive medications, providing alerts for redundant lab orders, sending and receiving imaging reports, and enabling structured medication reconciliation. Of the 54 high-scoring functionalities, 25 (46%) are represented in Stage 1 meaningful use. Many of the functionalities not yet represented in meaningful use correspond with functionalities that focus directly on healthcare utilization and costs rather than on healthcare quality per se. This work can inform the development and selection of future meaningful use measures; inform implementation efforts, as clinicians and hospitals choose from among a "menu" of measures for meaningful use; and inform evaluation efforts, as investigators seek to measure the actual financial impact of EHRs and HIE.

Nitrile functionalized halloysite nanotubes/poly(arylene ether nitrile) nanocomposites: Interface control, characterization, and improved properties

NASA Astrophysics Data System (ADS)

Wan, Xinyi; Zhan, Yingqing; Zeng, Guangyong; He, Yi

2017-01-01

To develop high-performance halloysite nanotube (HNT)-based nanocomposites, the two key issues need to be considered: precise interface control and the dispersal of HNTs. This study presents an efficient way to functionalize halloysite nanotubes with 3-aminophenoxy-phthalonitrile, followed by compounding with poly(arylene ether nitrile) (PEN), to prepare functional nanocomposite films. The surface functionalization of HNTs was characterized and confirmed by Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS), and transmission electron microscopy (TEM). Compared with neat PEN, the tensile strength and modulus of the resulting PEN nanocomposites with 3 wt% functionalized HNTs were found to increase by 25.7% and 20.7%, respectively. The good dispersion and high capacitance of the dielectric layer resulted in PEN/HNTs nancomposites with enhanced dielectric permittivity and relatively low dielectric loss. Moreover, the addition of functional HNTs greatly improved the thermal stability of PEN, which could be further enhanced through the chemical cross-linking reaction between the functional HNTs and the PEN matrix. This work provides a new path toward obtaining advanced polymer-based nanocomposites with functional properties.

Self-interest and other-orientation in organizational behavior: implications for job performance, prosocial behavior, and personal initiative.

PubMed

De Dreu, Carsten K W; Nauta, Aukje

2009-07-01

In this article, the authors develop the self-concern and other-orientation as moderators hypothesis. The authors argue that many theories on work behavior assume humans to be either self-interested or to be social in nature with strong other-orientation but that this assumption is empirically invalid and may lead to overly narrow models of work behavior. The authors instead propose that self-concern and other-orientation are independent. The authors also propose that job performance, prosocial behavior, and personal initiative are a function of (a) individual-level attributes, such as job characteristics when employees are high in self-concern, and (b) group-level attributes, such as justice climate when employees are high in other-orientation. Three studies involving 4 samples of employees from a variety of organizations support these propositions. Implications are discussed for theory on work behavior and interventions geared toward job enrichment and team-based working.

TH-A-9A-04: Incorporating Liver Functionality in Radiation Therapy Treatment Planning

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

Wu, V; Epelman, M; Feng, M

2014-06-15

Purpose: Liver SBRT patients have both variable pretreatment liver function (e.g., due to degree of cirrhosis and/or prior treatments) and sensitivity to radiation, leading to high variability in potential liver toxicity with similar doses. This work aims to explicitly incorporate liver perfusion into treatment planning to redistribute dose to preserve well-functioning areas without compromising target coverage. Methods: Voxel-based liver perfusion, a measure of functionality, was computed from dynamic contrast-enhanced MRI. Two optimization models with different cost functions subject to the same dose constraints (e.g., minimum target EUD and maximum critical structure EUDs) were compared. The cost functions minimized were EUDmore » (standard model) and functionality-weighted EUD (functional model) to the liver. The resulting treatment plans delivering the same target EUD were compared with respect to their DVHs, their dose wash difference, the average dose delivered to voxels of a particular perfusion level, and change in number of high-/low-functioning voxels receiving a particular dose. Two-dimensional synthetic and three-dimensional clinical examples were studied. Results: The DVHs of all structures of plans from each model were comparable. In contrast, in plans obtained with the functional model, the average dose delivered to high-/low-functioning voxels was lower/higher than in plans obtained with its standard counterpart. The number of high-/low-functioning voxels receiving high/low dose was lower in the plans that considered perfusion in the cost function than in the plans that did not. Redistribution of dose can be observed in the dose wash differences. Conclusion: Liver perfusion can be used during treatment planning potentially to minimize the risk of toxicity during liver SBRT, resulting in better global liver function. The functional model redistributes dose in the standard model from higher to lower functioning voxels, while achieving the same target EUD and satisfying dose limits to critical structures. This project is funded by MCubed and grant R01-CA132834.« less

Evidence for a double dissociation of articulatory rehearsal and non-articulatory maintenance of phonological information in human verbal working memory.

PubMed

Trost, Sarah; Gruber, Oliver

2012-01-01

Recent functional neuroimaging studies have provided evidence that human verbal working memory is represented by two complementary neural systems, a left lateralized premotor-parietal network implementing articulatory rehearsal and a presumably phylogenetically older bilateral anterior-prefrontal/inferior-parietal network subserving non-articulatory maintenance of phonological information. In order to corroborate these findings from functional neuroimaging, we performed a targeted behavioural study in patients with very selective and circumscribed brain lesions to key regions suggested to support these different subcomponents of human verbal working memory. Within a sample of over 500 neurological patients assessed with high-resolution structural magnetic resonance imaging, we identified 2 patients with corresponding brain lesions, one with an isolated lesion to Broca's area and the other with a selective lesion bilaterally to the anterior middle frontal gyrus. These 2 patients as well as groups of age-matched healthy controls performed two circuit-specific verbal working memory tasks. In this way, we systematically assessed the hypothesized selective behavioural effects of these brain lesions on the different subcomponents of verbal working memory in terms of a double dissociation. Confirming prior findings, the lesion to Broca's area led to reduced performance under articulatory rehearsal, whereas the non-articulatory maintenance of phonological information was unimpaired. Conversely, the bifrontopolar brain lesion was associated with impaired non-articulatory phonological working memory, whereas performance under articulatory rehearsal was unaffected. The present experimental neuropsychological study in patients with specific and circumscribed brain lesions confirms the hypothesized double dissociation of two complementary brain systems underlying verbal working memory in humans. In particular, the results demonstrate the functional relevance of the anterior prefrontal cortex for non-articulatory maintenance of phonological information and, in this way, provide further support for the evolutionary-based functional-neuroanatomical model of human working memory. Copyright © 2012 S. Karger AG, Basel.

Advanced Airborne Defensive Laser for Incorporation on Strike Fighter Aircraft

DTIC Science & Technology

2017-09-01

Systems within the Pod The Cyclops pod contains several systems working together to perform the high - level functions. The status of these systems must be...by the aircraft is limited, and Cyclops power requirements are high . commercial off-the-shelf (COTS) Ram Air Turbines are available and are...Supply Subsystem The Cyclops pod must generate its own power due to lack of available power from the aircraft; therefore, the Power supply has high

A theory of viscoplasticity accounting for internal damage

NASA Technical Reports Server (NTRS)

Freed, A. D.; Robinson, D. N.

1988-01-01

A constitutive theory for use in structural and durability analyses of high temperature isotropic alloys is presented. Constitutive equations based upon a potential function are determined from conditions of stability and physical considerations. The theory is self-consistent; terms are not added in an ad hoc manner. It extends a proven viscoplastic model by introducing the Kachanov-Rabotnov concept of net stress. Material degradation and inelastic deformation are unified; they evolve simultaneously and interactively. Both isotropic hardening and material degradation evolve with dissipated work which is the sum of inelastic work and internal work. Internal work is a continuum measure of the stored free energy resulting from inelastic deformation.

Connected Functional Working Spaces: A Framework for the Teaching and Learning of Functions at Upper Secondary Level

ERIC Educational Resources Information Center

Minh, Tran Kiem; Lagrange, Jean-Baptiste

2016-01-01

This paper aims at contributing to remedy the narrow treatment of functions at upper secondary level. Assuming that students make sense of functions by working on functional situations in distinctive settings, we propose to consider functional working spaces inspired by geometrical working spaces. We analyse a classroom situation based on a…

Phytozome Comparative Plant Genomics Portal

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

Goodstein, David; Batra, Sajeev; Carlson, Joseph

2014-09-09

The Dept. of Energy Joint Genome Institute is a genomics user facility supporting DOE mission science in the areas of Bioenergy, Carbon Cycling, and Biogeochemistry. The Plant Program at the JGI applies genomic, analytical, computational and informatics platforms and methods to: 1. Understand and accelerate the improvement (domestication) of bioenergy crops 2. Characterize and moderate plant response to climate change 3. Use comparative genomics to identify constrained elements and infer gene function 4. Build high quality genomic resource platforms of JGI Plant Flagship genomes for functional and experimental work 5. Expand functional genomic resources for Plant Flagship genomes

Interrelated structure of high altitude atmospheric profiles

NASA Technical Reports Server (NTRS)

Engler, N. A.; Goldschmidt, M. A.

1972-01-01

A preliminary development of a mathematical model to compute probabilities of thermodynamic profiles is presented. The model assumes an exponential expression for pressure and utilizes the hydrostatic law and equation of state in the determination of density and temperature. It is shown that each thermodynamic variable can be factored into the produce of steady state and perturbation functions. The steady state functions have profiles similar to those of the 1962 standard atmosphere while the perturbation functions oscillate about 1. Limitations of the model and recommendations for future work are presented.

The effect of stress induction on working memory in patients with psychogenic nonepileptic seizures.

PubMed

Bakvis, Patricia; Spinhoven, Philip; Putman, Peter; Zitman, Frans G; Roelofs, Karin

2010-11-01

Although psychogenic nonepileptic seizures (PNES) are considered a stress-induced paroxysmal disintegration of cognitive functions, it remains unknown whether stress indeed impairs cognitive integrative functions, such as working memory (WM), in patients with PNES. An N-back task with emotional distracters (angry, happy, and neutral faces) was administered at baseline and after stress induction (Cold Pressor Test) to 19 patients with PNES and 20 matched healthy controls. At baseline, patients displayed increased WM interference for the facial distracters. After stress induction, group differences generalized to the no-distracter condition. Within patients, high cortisol stress responses were associated with larger stress-induced WM impairments in the no-distracter condition. These findings demonstrate that patients' cognitive integrative functions are impaired by social distracters and stress induction. Moreover, the stress- and cortisol-related generalization of the relative WM impairments offers a promising experimental model for the characteristic paroxysmal disintegration of attentional and mnemonic functions in patients with PNES associated with stress. Copyright © 2010 Elsevier Inc. All rights reserved.

The Effect of Executive Function on Science Achievement Among Normally Developing 10-Year Olds

NASA Astrophysics Data System (ADS)

Lederman, Sheri G.

Executive function (EF) is an umbrella term used to identify a set of discrete but interrelated cognitive abilities that enable individuals to engage in goal-directed, future-oriented action in response to a novel context. Developmental studies indicate that EF is predictive of reading and math achievement in middle childhood. The purpose of this study was to identify the association between EF and science achievement among normally developing 10 year olds. A sample of fifth grade students from a Northeastern suburban community participated in tests of EF, science, and intelligence. Consistent with adult models of EF, principal components analysis identified a three-factor model of EF organization in middle childhood, including cognitive flexibility, working memory, and inhibition. Multiple regression analyses revealed that executive function processes of cognitive flexibility, working memory, and inhibition were all predictive of science performance. Post hoc analyses revealed that high-performing science students differed significantly from low-performing students in both cognitive flexibility and working memory. These findings suggest that complex academic demands specific to science achievement rely on the emergence and maturation of EF components.

Subtypes and comorbidity in mathematical learning disabilities: Multidimensional study of verbal and visual memory processes is key to understanding.

PubMed

Szűcs, D

2016-01-01

A large body of research suggests that mathematical learning disability (MLD) is related to working memory impairment. Here, I organize part of this literature through a meta-analysis of 36 studies with 665 MLD and 1049 control participants. I demonstrate that one subtype of MLD is associated with reading problems and weak verbal short-term and working memory. Another subtype of MLD does not have associated reading problems and is linked to weak visuospatial short-term and working memory. In order to better understand MLD we need to precisely define potentially modality-specific memory subprocesses and supporting executive functions, relevant for mathematical learning. This can be achieved by taking a multidimensional parametric approach systematically probing an extended network of cognitive functions. Rather than creating arbitrary subgroups and/or focus on a single factor, highly powered studies need to position individuals in a multidimensional parametric space. This will allow us to understand the multidimensional structure of cognitive functions and their relationship to mathematical performance. © 2016 Elsevier B.V. All rights reserved.

Chemically doped three-dimensional porous graphene monoliths for high-performance flexible field emitters.

PubMed

Kim, Ho Young; Jeong, Sooyeon; Jeong, Seung Yol; Baeg, Kang-Jun; Han, Joong Tark; Jeong, Mun Seok; Lee, Geon-Woong; Jeong, Hee Jin

2015-03-12

Despite the recent progress in the fabrication of field emitters based on graphene nanosheets, their morphological and electrical properties, which affect their degree of field enhancement as well as the electron tunnelling barrier height, should be controlled to allow for better field-emission properties. Here we report a method that allows the synthesis of graphene-based emitters with a high field-enhancement factor and a low work function. The method involves forming monolithic three-dimensional (3D) graphene structures by freeze-drying of a highly concentrated graphene paste and subsequent work-function engineering by chemical doping. Graphene structures with vertically aligned edges were successfully fabricated by the freeze-drying process. Furthermore, their number density could be controlled by varying the composition of the graphene paste. Al- and Au-doped 3D graphene emitters were fabricated by introducing the corresponding dopant solutions into the graphene sheets. The resulting field-emission characteristics of the resulting emitters are discussed. The synthesized 3D graphene emitters were highly flexible, maintaining their field-emission properties even when bent at large angles. This is attributed to the high crystallinity and emitter density and good chemical stability of the 3D graphene emitters, as well as to the strong interactions between the 3D graphene emitters and the substrate.

Neuromuscular control of lumbar instability following static work of various loads.

PubMed

Le, Brook; Davidson, Bradley; Solomonow, Deborah; Zhou, Bing He; Lu, Yun; Patel, Vikas; Solomonow, Moshe

2009-01-01

Neuromuscular control of lumbar stability following exposure to prolonged static work, under low and high loads, was assessed in the in vivo feline model. Six sessions of 10 min work at 20N with 10 min between rest was compared to a group subjected to the same protocol but carrying high loads of 60N. Displacement and tension developed in the spine at the instant the multifidus muscles applied stabilizing contractions, and their amplitudes were obtained from their electromyogram (EMG). Significant (P < 0.001) laxity developed in the various viscoelastic tissues of the lumbar spine that did not recover during and up to 7 h of rest postwork. Simultaneously, there was a significant (P < 0.001) decrease in muscular activity in the 3-4 h immediately postwork under low load but only during the first hour in the high load group. After that period the musculature compensated for the laxity of the viscoelastic tissues by a significant (P < 0.001) increase in activity in the high-load group and a nonsignificant increase in the low group. It was concluded that during 1-3 h immediately poststatic work a significant decrease in the stabilizing function of viscoelastic tissues together with a significant decrease in muscular activity is present, and they render the spine unstable and exposed to high risk of injury. Performance of prolonged static work under low loads, while not harmful during the work, cannot be designated as a "no-risk" condition, as it may result in injury postwork.

Are disease severity, sleep-related problems, and anxiety associated with work functioning in patients with obstructive sleep apnoea?

PubMed

Timkova, Vladimira; Nagyova, Iveta; Reijneveld, Sijmen A; Tkacova, Ruzena; van Dijk, Jitse P; Bültmann, Ute

2018-04-17

To examine whether Obstructive Sleep Apnoea severity, sleep-related problems, and anxiety are associated with work functioning in Obstructive Sleep Apnoea patients, when controlled for age, gender and type of occupation. To investigate whether anxiety moderates the associations between sleep-related problems and work functioning. We included 105 Obstructive Sleep Apnoea patients (70% male; mean age 46.62 ± 9.79 years). All patients completed the Pittsburgh Sleep Quality Index, the Epworth Sleepiness Scale, the Beck Anxiety Inventory, and the Work Role Functioning Questionnaire-2.0. Obstructive Sleep Apnoea-severity, poor nighttime sleep quality, and anxiety were univariately associated with impaired work functioning. Multivariate analyzes revealed that poor perceived sleep quality was more strongly associated with work functioning than sleep efficiency and daily disturbances. Anxiety was strongly associated with impaired work functioning. After adding anxiety, the explained variance in work functioning increased from 20% to 25%. Anxiety moderated the association between low and medium levels of nighttime sleep quality problems and work functioning. Poor perceived sleep quality and anxiety were strongly associated with impaired work functioning in Obstructive Sleep Apnoea patients. These findings may help to optimize management, standard treatment, and work functioning in people with Obstructive Sleep Apnoea when confirmed in longitudinal studies. Implications for Rehabilitation Studies show an impairment of functional status, including work functioning, in obstructive sleep apnea patients. Aside from physical disorders, obstructive sleep apnea patients often experience mental problems, such as anxiety. As many people with obstructive sleep apnea are undiagnosed, our results demonstrate to employers and healthcare professionals the need to encourage patients for obstructive sleep apnea screening, especially in the situation of impaired work functioning, increased anxiety, and poor sleep quality. The associations between obstructive sleep apnea, sleep and anxiety might increase the awareness of health professionals towards optimizing diagnostic accuracy and standard treatment.

Work fluctuations for Bose particles in grand canonical initial states.

PubMed

Yi, Juyeon; Kim, Yong Woon; Talkner, Peter

2012-05-01

We consider bosons in a harmonic trap and investigate the fluctuations of the work performed by an adiabatic change of the trap curvature. Depending on the reservoir conditions such as temperature and chemical potential that provide the initial equilibrium state, the exponentiated work average (EWA) defined in the context of the Crooks relation and the Jarzynski equality may diverge if the trap becomes wider. We investigate how the probability distribution function (PDF) of the work signals this divergence. It is shown that at low temperatures the PDF is highly asymmetric with a steep fall-off at one side and an exponential tail at the other side. For high temperatures it is closer to a symmetric distribution approaching a Gaussian form. These properties of the work PDF are discussed in relation to the convergence of the EWA and to the existence of the hypothetical equilibrium state to which those thermodynamic potential changes refer that enter both the Crooks relation and the Jarzynski equality.

[Occupational complexity and late-life memory and reasoning abilities].

PubMed

Ishioka, Yoshiko; Gondo, Yasuyuki; Masui, Yukie; Nakagawa, Takeshi; Tabuchi, Megumi; Ogawa, Madoka; Kamide, Kei; Ikebe, Kazunori; Arai, Yasumichi; Ishizaki, Tatsuro; Takahashi, Ryutaro

2015-08-01

This study examined the associations between the complexity of an individual's primary lifetime occupation and his or her late-life memory and reasoning performance, using data from 824 community-dwelling participants aged 69-72 years. The complexity of work with data, people, and things was evaluated based on the Japanese job complexity score. The associations between occupational complexity and participant's memory and reasoning abilities were examined in multiple regression analyses. An association was found between more comple work with people and higher memory performance, as well as between more complex work with data and higher reasoning performance, after having controlled for gender, school records, and education. Further, an interaction effect was observed between gender and complexity of work with data in relation to reasoning performance: work involving a high degree of complexity with data was associated with high reasoning performance in men. These findings suggest the need to consider late-life cognitive functioning within the context of adulthood experiences, specifically those related to occupation and gender.

Respiratory effects among rubberwood furniture factory workers in Thailand.

PubMed

Sriproed, Salakjit; Osiri, Pramuk; Sujirarat, Dusit; Chantanakul, Suttinun; Harncharoen, Kitiphong; Ong-artborirak, Parichat; Woskie, Susan R

2013-01-01

Respiratory symptoms and pulmonary function were examined among 89 rubberwood furniture factory workers. Acute and chronic irritant symptoms were assessed, lung function was measured both pre- and post-shift and personal inhalable dust exposure determined. The only symptoms with a significant increase among high dust level-exposed workers (>1 mg/m(3)) were those related to nasal irritation. High dust level-exposed workers had a significant cross-shift decrease in forced expiratory volume in 1 second/forced vital capacity (FEV(1)/FVC) compared with low dust level-exposed workers and increases in inhalable dust concentration levels (mg/m(3)) were significantly associated with decreases in the peak expiratory flow (PEF) across the work shift. For percent predicted pulmonary function levels, a significant decrement in PEF was found for high versus low rubberwood dust level-exposed workers, after controlling for confounders. These findings suggest the need for an occupational standard for rubberwood dust in Thailand.

Age differences in high frequency phasic heart rate variability and performance response to increased executive function load in three executive function tasks

PubMed Central

Byrd, Dana L.; Reuther, Erin T.; McNamara, Joseph P. H.; DeLucca, Teri L.; Berg, William K.

2015-01-01

The current study examines similarity or disparity of a frontally mediated physiological response of mental effort among multiple executive functioning tasks between children and adults. Task performance and phasic heart rate variability (HRV) were recorded in children (6 to 10 years old) and adults in an examination of age differences in executive functioning skills during periods of increased demand. Executive load levels were varied by increasing the difficulty levels of three executive functioning tasks: inhibition (IN), working memory (WM), and planning/problem solving (PL). Behavioral performance decreased in all tasks with increased executive demand in both children and adults. Adults’ phasic high frequency HRV was suppressed during the management of increased IN and WM load. Children’s phasic HRV was suppressed during the management of moderate WM load. HRV was not suppressed during either children’s or adults’ increasing load during the PL task. High frequency phasic HRV may be most sensitive to executive function tasks that have a time-response pressure, and simply requiring performance on a self-paced task requiring frontal lobe activation may not be enough to generate HRV responsitivity to increasing demand. PMID:25798113

Autonomous multifunctional nanobrushes-autonomous materials

NASA Astrophysics Data System (ADS)

Ghasemi-Nejhad, Mehrdad N.; Tius, Marcus A.

2007-04-01

In this work, taking advantage of carbon nanotubes' small size, and exceptional mechanical, chemical and electrical properties, we report on a series of nano-synthesis procedures that combine conventional chemical vapor deposition and selective substrate area growth followed by chemical functionalizations to fabricate functionalized nano-brushes from aligned carbon nanotube arrays and chemically selective functional groups. The high aspect ratio and small dimension, mechanical stability and flexibility, surface chemical and adhesive characteristics of carbon nanotubes provide opportunities to create nano-brushes with selected chemical functionalities. The nano-brushes are made from aligned multi-walled carbon nanotube bristles grafted onto long SiC fiber handles in various configurations and functionalized with various chemical functional groups. These nano-brushes can easily be manipulated physically, either manually or with the aid of motors. Here, we explain the autonomous characteristics of the functionalized nano-brushes employing functional chemical groups such that the nano-brush can potentially collect various metal particles, ions, and contaminants from liquid solutions and the air environment, autonomously. These functionalized multiwalled carbon nanotube based nano-brushes can work swiftly in both liquid and air environments. With surface modification and functionalization, the nanotube nano-brushes can potentially become a versatile nano-devices in many chemical and biological applications, where they can autonomously pick up the particles they encounter since they can be chemically programmed to function as Autonomous Chemical Nano Robots (ACNR).

Biological monitoring of glazers exposed to lead in the ceramics industry in Iran.

PubMed

Shouroki, Fatemeh Kargar; Shahtaheri, Seyed Jamaleddin; Golbabaei, Farideh; Barkhordari, Abolfazle; Rahimi-Froushani, Abbas

2015-01-01

Exposure to heavy metals, particularly lead, takes place in the ceramics industry. Lead is used in glaze to produce smooth and brilliant surfaces; thus, there is a likelihood of occupational adverse effects on humans. Urine samples were collected from 49 glazers at the start and end of the work shifts (98 samples). Solid phase extraction was used for separation and pre-concentration of the analyte. Samples were analysed by inductively coupled plasma-atomic emission spectroscopy (ICP-AES). Lung function tests were performed on both control and lead exposed subjects. Statistical analysis of covariance (ANCOVA) was used to evaluate the data obtained. The concentration of lead in glazers was 6.37 times higher than in the control group. Lung functions were significantly lower in the glazers compared to the control group (p < 0.001). Results showed that poor ventilation systems, overtime work and work history are effective determinants of high exposure levels.

Overcoming barriers to work participation for patients with postpoliomyelitis syndrome.

PubMed

Ten Katen, Kim; Beelen, Anita; Nollet, Frans; Frings-Dresen, Monique H W; Sluiter, Judith K

2011-01-01

This study aimed to explore the perceived work ability of patients with postpoliomyelitis syndrome (PPS), to identify barriers and factors that are impeding or conducive, respectively, to work participation, and to identify possible interventions. Qualitative cross-sectional interview study with 17 subjects with PPS, 12 women and 5 men, mean age 49 years (SD: 11). Semi-structured interviews were held with the subjects in their homes, with the aid of a topic list. The COREQ criteria list for qualitative research was used as guideline in design and analysis. Thirteen out of 17 subjects rated their work ability six or higher on a scale from 0 to 10. Most subjects worked in an administrative, educational or managerial function. Five subjects stopped working, four worked between 0 and 20 h/week and eight worked between 20 and 40 h/week. Factors conducive to working were physical adaptations in the workplace, accessibility of the workplace and high decision latitude. Barriers to full work ability in PPS patients were high physical job demands, low social support and the symptoms of PPS, especially fatigue and pain. These findings suggest that work-oriented interventions aimed at preventing PPS patients from dropping out of the workforce should primarily focus on reducing physical job demands, arranging adaptations in the workplace and increasing job control.

Alcohol Attenuates Load-related Activation During a Working Memory Task: Relation to Level of Response to Alcohol

PubMed Central

Paulus, Martin P.; Tapert, Susan F.; Pulido, Carmen; Schuckit, Marc A.

2008-01-01

Background A low level of response to alcohol is a major risk factor for the development of alcohol dependence, but neural correlates of this marker are unclear. Method Ten healthy volunteers were classified by median split on level of response to alcohol and underwent 2 sessions of functional magnetic resonance imaging following ingestion of a moderate dose of alcohol and a placebo. The blood oxygen level–dependent activation to an event-related visual working memory test was examined. Results The subjects exhibited longer response latencies and more errors as a function of increasing working memory load and showed a load-dependent increase in activation in dorsolateral prefrontal cortex, posterior parietal cortex, and visual cortex. Alcohol did not affect performance (errors or response latency), but attenuated the working memory load–dependent activation in the dorsolateral prefrontal cortex. During the placebo condition, individuals with a low level of response to alcohol showed greater activation in dorsolateral prefrontal cortex and posterior parietal cortex than those with a high level of response to alcohol. During the alcohol condition, groups showed similar attenuation of load-dependent brain activation in these regions. Conclusion Low-level responders relative to high-level responders exhibited an increased working memory load–dependent activation in dorsolateral prefrontal cortex and posterior parietal cortex when not exposed to alcohol. This increase in brain response was attenuated in low-level responders after ingesting a moderate dose of alcohol. PMID:16899039

Neuropsychological Functioning in Adolescents and Young Adults at Genetic Risk for Schizophrenia and Affective Psychoses: Results from the Harvard and Hillside Adolescent High Risk Studies

PubMed Central

Seidman, Larry J.; Giuliano, Anthony J.; Smith, Christopher W.; Stone, William S.; Glatt, Stephen J.; Meyer, Eric; Faraone, Stephen V.; Tsuang, Ming T.; Cornblatt, Barbara

2006-01-01

Siblings and offspring of persons with schizophrenia carry elevated genetic risk for the illness and manifest attentional and memory impairments. Because less is known about other neuropsychological functions and their specificity in adolescents, we conducted a genetic high-risk (HR) study of schizophrenia (HR-SCZ) and affective psychosis (HR-AFF). Participants (ages 12–25) were from the Harvard Adolescent High-Risk and Hillside Family studies, including 73 HR-SCZ, 18 HR-AFF, and 84 community controls (CCs) recruited in metropolitan Boston and New York. Groups were compared on overall neurocognitive functioning, 6 domains, and 13 test scores, controlling for age, parental education, and correlated data within families. The HR-SCZ group was significantly impaired overall, while the HR-AFF group demonstrated a trend toward overall impairment. HR-SCZ subjects showed significantly lower Verbal Ability (d = .73) and Executive Functioning/Working Memory (d = .47) than CCs. HR-AFF subjects showed reduced Verbal Ability (d = .64) compared to CCs. Excluding 12 CCs with a parental history of depression (without psychosis) led to larger differences between HR and CC groups across domains. Moreover, HR-SCZ and CC group differences in Verbal Memory (d = .39) and Visual-Spatial (d = .34) became statistically significant. There were no significant differences between HR-SCZ and HR-AFF groups. Data support a modest neuropsychological deficit in persons at genetic HR for psychosis, with a broader range of deficits in HR-SCZ. Future work should assess the relationship of neurocognition to adaptive functioning and possible onset of psychosis in HR samples. Ascertainment criteria for controls may markedly influence results and interpretation of group differences. PMID:16707777

High work-function hole transport layers by self-assembly using a fluorinated additive

DOE PAGES

Mauger, Scott A.; Li, Jun; Özmen, Özge Tüzün; ...

2013-10-30

The hole transport polymer poly(3,4-ethylenedioxythiophene):poly(4-styrenesulfonate) (PEDOT:PSS) derives many of its favorable properties from a PSS-rich interfacial layer that forms spontaneously during coating. Since PEDOT:PSS is only usable as a blend it is not possible to study PEDOT:PSS without this interfacial layer. Through the use of the self-doped polymer sulfonated poly(thiophene-3-[2-(2-methoxyethoxy) ethoxy]-2,5-diyl) (S-P3MEET) and a polyfluorinated ionomer (PFI) it is possible to compare transparent conducting organic films with and without interfacial layers and to understand their function. Using neutron reflectometry, we show that PFI preferentially segregates at the top surface of the film during coating and forms a thermally stable surfacemore » layer. Because of this distribution we find that even small amounts of PFI increase the electron work function of the HTL. We also find that annealing at 150°C and above reduces the work function compared to samples heated at lower temperatures. Using near edge x-ray absorption fine structure spectroscopy and gas chromatography we show that this reduction in work function is due to S-P3MEET being doped by PFI. Organic photovoltaic devices with S-P3MEET/PFI hole transport layers yield higher power conversion efficiency than devices with pure S-P3MEET or PEDOT:PSS hole transport layers. Additionally, devices with a doped interface layer of S-P3MEET/PFI show superior performance to those with un-doped S-P3MEET.« less

Novel trends in pair distribution function approaches on bulk systems with nanoscale heterogeneities

DOE PAGES

Emil S. Bozin; Billinge, Simon J. L.

2016-07-29

Novel materials for high performance applications increasingly exhibit structural order on the nanometer length scale; a domain where crystallography, the basis of Rietveld refinement, fails [1]. In such instances the total scattering approach, which treats Bragg and diffuse scattering on an equal basis, is a powerful approach. In recent years, the analysis of the total scattering data became an invaluable tool and the gold standard for studying nanocrystalline, nanoporous, and disordered crystalline materials. The data may be analyzed in reciprocal space directly, or Fourier transformed to the real-space atomic pair distribution function (PDF) and this intuitive function examined for localmore » structural information. Here we give a number of illustrative examples, for convenience picked from our own work, of recent developments and applications of total scattering and PDF analysis to novel complex materials. There are many other wonderful examples from the work of others.« less

In situ synthesis of silver nanoparticles uniformly distributed on polydopamine-coated silk fibers for antibacterial application.

PubMed

Lu, Zhisong; Xiao, Jing; Wang, Ying; Meng, Mei

2015-08-15

Fabrication of silver nanoparticles (AgNPs)-modified silk for antibacterial application is one of the hottest topics in the textile material research. However, the utilization of a polymer as both 3-dimensional matrix and reductant for the in-situ synthesis of AgNPs on silk fibers has not been realized. In this work, a facile, efficient and green approach was developed to in-situ grow AgNPs on the polydopamine (PDA)-functionalized silk. AgNPs with the size of 30-90 nm were uniformly deposited on the silk fiber surface with the PDA coating layer as a reduction reagent. The AgNPs exhibit excellent face-centered cubic crystalline structures. The bacterial growth curve and inhibition zone assays clearly demonstrate the antibacterial properties of the functionalized silk. Both high Ag(+) release level and long-time release profile were observed for the as-prepared AgNPs-PDA-coated silk, indicating the high-density loading of AgNPs and the possible long-term antibacterial effects. This work may provide a new method for the preparation of AgNPs-functionalized silk with antibacterial activity for the clothing and textile industry. Copyright © 2015 Elsevier Inc. All rights reserved.

Increased functional properties and thermal stability of flexible cellulose nanocrystal/ZnO films.

PubMed

Lizundia, E; Urruchi, A; Vilas, J L; León, L M

2016-01-20

In this work we attempt to improve the functional properties and thermal stability of cellulose nanocrystal (CNC) films by means of eco-friendly materials and processes. Mechanically flexible films of closely packed CNCs with concentrations up to 5 wt.% of zinc oxide (ZnO) nanoparticles have been prepared by a simple, standard and environmentally friendly method using solely water. Results reveal that ultraviolet light is blocked by 98.5% at 1 wt.% ZnO while good transparency is maintained. A sharp hydrophobicity increase is observed with the addition of ZnO which would enhance the durability of films by decreasing the water diffusion through the material. The thermal degradation activation energy (E) presents an increase of 141%, denoting a high thermal stability of films, which would result beneficial for their potential application in the field of flexible electronics. Mechanical results demonstrate a high structural integrity of CNC/ZnO as a result of the occurring strong cellulosic inter- and intramolecular interactions within the closely packed CNC network. In overall, this work highlights the potential for environmentally friendly processing of sustainable nanostructured functional materials based on cellulose. Copyright © 2015 Elsevier Ltd. All rights reserved.

Work Functions for Models of Scandate Surfaces

NASA Technical Reports Server (NTRS)

Mueller, Wolfgang

1997-01-01

The electronic structure, surface dipole properties, and work functions of scandate surfaces have been investigated using the fully relativistic scattered-wave cluster approach. Three different types of model surfaces are considered: (1) a monolayer of Ba-Sc-O on W(100), (2) Ba or BaO adsorbed on Sc2O3 + W, and (3) BaO on SC2O3 + WO3. Changes in the work function due to Ba or BaO adsorption on the different surfaces are calculated by employing the depolarization model of interacting surface dipoles. The largest work function change and the lowest work function of 1.54 eV are obtained for Ba adsorbed on the Sc-O monolayer on W(100). The adsorption of Ba on Sc2O3 + W does not lead to a low work function, but the adsorption of BaO results in a work function of about 1.6-1.9 eV. BaO adsorbed on Sc2O3 + WO3, or scandium tungstates, may also lead to low work functions.

Allocating effort and anticipating pleasure in schizophrenia: Relationship with real world functioning.

PubMed

Serper, M; Payne, E; Dill, C; Portillo, C; Taliercio, J

2017-10-01

Poor motivation to engage in goal-oriented behavior has been recognized as a hallmark feature of schizophrenia spectrum disorders (SZ). Low drive in SZ may be related to anticipating rewards as well as to poor working memory. However, few studies to date have examined beliefs about self-efficacy and satisfaction for future rewards (anticipatory pleasure). Additionally, few studies to date have examined how these deficits may impact SZ patients' real world functioning. The present study examined SZ patients' (n=57) anticipatory pleasure, working memory, self-efficacy and real world functioning in relation to their negative symptom severity. Results revealed that SZ patients' negative symptom severity was related to decisions in effort allocation and reward probability, working memory deficits, self-efficacy and anticipatory pleasure for future reward. Effort allocation deficits also predicted patients' daily functioning skills. SZ patients with high levels of negative symptoms are not merely effort averse, but have more difficulty effectively allocating effort and anticipating pleasure engaging in effortful activities. It may be the case that continuously failing to achieve reinforcement from engagement and participation may lead SZ patients to form certain negative beliefs about their abilities which contributes to amotivation and cognitive deficits. Lastly, our findings provide further support for a link between SZ patients functional daily living skills their effort allocation. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Standing Up for Learning: A Pilot Investigation on the Neurocognitive Benefits of Stand-Biased School Desks

PubMed Central

Mehta, Ranjana K.; Shortz, Ashley E.; Benden, Mark E.

2015-01-01

Standing desks have proven to be effective and viable solutions to combat sedentary behavior among children during the school day in studies around the world. However, little is known regarding the potential of such interventions on cognitive outcomes in children over time. The purpose of this pilot study was to determine the neurocognitive benefits, i.e., improvements in executive functioning and working memory, of stand-biased desks and explore any associated changes in frontal brain function. 34 freshman high school students were recruited for neurocognitive testing at two time points during the school year: (1) in the fall semester and (2) in the spring semester (after 27.57 (1.63) weeks of continued exposure). Executive function and working memory was evaluated using a computerized neurocognitive test battery, and brain activation patterns of the prefrontal cortex were obtained using functional near infrared spectroscopy. Continued utilization of the stand-biased desks was associated with significant improvements in executive function and working memory capabilities. Changes in corresponding brain activation patterns were also observed. These findings provide the first preliminary evidence on the neurocognitive benefits of standing desks, which to date have focused largely on energy expenditure. Findings obtained here can drive future research with larger samples and multiple schools, with comparison groups that may in turn implicate the importance of stand-biased desks, as simple environmental changes in classrooms, on enhancing children’s cognitive functioning that drive their cognitive development and impact educational outcomes. PMID:26703700

Effect of Thermomechanical Processing on the Microstructure, Properties, and Work Behavior of a Ti50.5 Ni29.5 Pt20 High-Temperature Shape Memory Alloy

NASA Technical Reports Server (NTRS)

Noebe, Ronald; Draper, Susan; Gaydosh, Darrell; Garga, Anita; Lerch, Brad; Penney, Nicholas; Begelow, Glen; Padula, Santo, II; Brown, Jeff

2006-01-01

TiNiPt shape memory alloys are particularly promising for use as solid state actuators in environments up to 300 C, due to a reasonable balance of properties, including acceptable work output. However, one of the challenges to commercializing a viable high-temperature shape memory alloy (HTSMA) is to establish the appropriate primary and secondary processing techniques for fabrication of the material in a required product form such as rod and wire. Consequently, a Ti(50.5)Ni(29.5)Pt20 alloy was processed using several techniques including single-pass high-temperature extrusion, multiple-pass high-temperature extrusion, and cold drawing to produce bar stock, thin rod, and fine wire, respectively. The effects of heat treatment on the hardness, grain size, room temperature tensile properties, and transformation temperatures of hot- and cold-worked material were examined. Basic tensile properties as a function of temperature and the strain-temperature response of the alloy under constant load, for the determination of work output, were also investigated for various forms of the Ti(50.5)Ni(29.5)Pt20 alloy, including fine wire.

Effects of emotional stimuli on working memory processes in male criminal offenders with borderline and antisocial personality disorder.

PubMed

Prehn, Kristin; Schulze, Lars; Rossmann, Sabine; Berger, Christoph; Vohs, Knut; Fleischer, Monika; Hauenstein, Karlheinz; Keiper, Peter; Domes, Gregor; Herpertz, Sabine C

2013-02-01

OBJECTIVE. In the present study, we aimed to investigate the influence of concurrently presented emotional stimuli on cognitive task processing in violent criminal offenders primarily characterized by affective instability. METHODS. Fifteen male criminal offenders with antisocial and borderline personality disorder (ASPD and BPD) and 17 healthy controls underwent functional magnetic resonance imaging (fMRI) while performing a working memory task with low and high working memory load. In a second experimental run, to investigate the interaction of emotion and cognition, we presented emotionally neutral, low, or high salient social scenes in the background of the task. RESULTS. During the memory task without pictures, both groups did not differ in general task performance and neural representation of working memory processes. During the memory task with emotional background pictures, however, ASPD-BPD subjects compared to healthy controls showed delayed responses and enhanced activation of the left amygdala in the presence of emotionally high salient pictures independent of working memory load. CONCLUSIONS. These results illustrate an interaction of emotion and cognition in affective instable individuals with enhanced reactivity to emotionally salient stimuli which might be an important factor regarding the understanding of aggressive and violent behaviour in these individuals.

The Influence of High Computer Access on Schoolwork and Student Empowerment: An Exploratory Study of the Nashville ACOT Site.

ERIC Educational Resources Information Center

Fisher, Charles W.

This study examines the relationship between high computer access and "student empowerment" at the Nashville, Tennessee, site of the Apple Classroom of Tomorrow (ACOT) project. The study rests on the premise that school learning is a function of the work carried out by students in school, and that schoolwork is experienced by students as…

Capabilities for managing high-volume production of electric engineering equipment at the Electrochemical Production Plant

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

Podlednev, V.M.

1996-04-01

The Electromechanical Production Plant is essentially a research center with experimental facilities and power full testing base. Major products of the plant today include heat pipes and devices of their basis of different functions and power from high temperature ranges to cryogenics. This report describes work on porous titanium and carbon-graphite current collectors, electrocatalyst synthesis, and electrocatalyst applications.

The Structure of Working Memory Abilities across the Adult Life Span

PubMed Central

Hale, Sandra; Rose, Nathan S.; Myerson, Joel; Strube, Michael J; Sommers, Mitchell; Tye-Murray, Nancy; Spehar, Brent

2010-01-01

The present study addresses three questions regarding age differences in working memory: (1) whether performance on complex span tasks decreases as a function of age at a faster rate than performance on simple span tasks; (2) whether spatial working memory decreases at a faster rate than verbal working memory; and (3) whether the structure of working memory abilities is different for different age groups. Adults, ages 20–89 (n=388), performed three simple and three complex verbal span tasks and three simple and three complex spatial memory tasks. Performance on the spatial tasks decreased at faster rates as a function of age than performance on the verbal tasks, but within each domain, performance on complex and simple span tasks decreased at the same rates. Confirmatory factor analyses revealed that domain-differentiated models yielded better fits than models involving domain-general constructs, providing further evidence of the need to distinguish verbal and spatial working memory abilities. Regardless of which domain-differentiated model was examined, and despite the faster rates of decrease in the spatial domain, age group comparisons revealed that the factor structure of working memory abilities was highly similar in younger and older adults and showed no evidence of age-related dedifferentiation. PMID:21299306

Energy level alignment at molecule-metal interfaces from an optimally tuned range-separated hybrid functional

NASA Astrophysics Data System (ADS)

Liu, Zhen-Fei; Egger, David A.; Refaely-Abramson, Sivan; Kronik, Leeor; Neaton, Jeffrey B.

2017-03-01

The alignment of the frontier orbital energies of an adsorbed molecule with the substrate Fermi level at metal-organic interfaces is a fundamental observable of significant practical importance in nanoscience and beyond. Typical density functional theory calculations, especially those using local and semi-local functionals, often underestimate level alignment leading to inaccurate electronic structure and charge transport properties. In this work, we develop a new fully self-consistent predictive scheme to accurately compute level alignment at certain classes of complex heterogeneous molecule-metal interfaces based on optimally tuned range-separated hybrid functionals. Starting from a highly accurate description of the gas-phase electronic structure, our method by construction captures important nonlocal surface polarization effects via tuning of the long-range screened exchange in a range-separated hybrid in a non-empirical and system-specific manner. We implement this functional in a plane-wave code and apply it to several physisorbed and chemisorbed molecule-metal interface systems. Our results are in quantitative agreement with experiments, the both the level alignment and work function changes. Our approach constitutes a new practical scheme for accurate and efficient calculations of the electronic structure of molecule-metal interfaces.

Working Memory Capacity and Fluid Intelligence: Maintenance and Disengagement.

PubMed

Shipstead, Zach; Harrison, Tyler L; Engle, Randall W

2016-11-01

Working memory capacity and fluid intelligence have been demonstrated to be strongly correlated traits. Typically, high working memory capacity is believed to facilitate reasoning through accurate maintenance of relevant information. In this article, we present a proposal reframing this issue, such that tests of working memory capacity and fluid intelligence are seen as measuring complementary processes that facilitate complex cognition. Respectively, these are the ability to maintain access to critical information and the ability to disengage from or block outdated information. In the realm of problem solving, high working memory capacity allows a person to represent and maintain a problem accurately and stably, so that hypothesis testing can be conducted. However, as hypotheses are disproven or become untenable, disengaging from outdated problem solving attempts becomes important so that new hypotheses can be generated and tested. From this perspective, the strong correlation between working memory capacity and fluid intelligence is due not to one ability having a causal influence on the other but to separate attention-demanding mental functions that can be contrary to one another but are organized around top-down processing goals. © The Author(s) 2016.

[Workload, work satisfaction and burnout among Hungarian female residents. Results of representative, online survey].

PubMed

Győrffy, Zsuzsa; Girasek, Edmond

2014-11-16

Years of residency are the most challenging period of a medical carrier. The aim of this study was to analyze female residents' (n = 380) workload, work satisfaction and burnout. Data in this representative, cross-sectional epidemiological study were obtained from online questionnaires completed by 380 female residents. For a wider interpretation of the data, male residents (n = 176) were included in the analysis as a control group. The average weakly work hours of female residents were 66 hours and 70% of them felt overloaded. The medium and high level personal accomplishment was 75.9%, the emotional exhaustion was 58% and the medium and high level of depersonalization subscale was 53%. Female residents were mostly dissatisfied with working conditions, financial status, and prestige of her work. Dissatisfaction with the Hungarian health system was about 80% and nearly a quarter of respondents were considering working abroad. Female residents represent the "critical mass" of the young doctors. Residents' well-being is an important indicator of the functioning and effectiveness of the health care system.

Electronic properties of functionalized (5,5) beryllium oxide nanotubes.

PubMed

Chigo Anota, Ernesto; Cocoletzi, Gregorio Hernández

2013-05-01

Using the density functional theory (DFT) we study the structural and electronic properties of functionalized (5,5) chirality single wall beryllium oxide nanotubes (SW-BeONTs), i.e. armchair nanotubes. The nanotube surface and ends are functionalized by the hydroxyl (OH) functional group. Our calculations consider the Hamprecht-Cohen-Tozer-Handy functional in the generalized gradient approximation (HCTH-GGA) to deal with the exchange-correlation energies, and the base function with double polarization (DNP). The geometry optimization of both defects free and with point defects nanotubes is done applying the criterion of minimum energy. Six configurations are considered: The OH oriented toward the Be (on the surface and at the end), toward the O (on the surface and at the end) and placed at the nanotube ends. Simulation results show that the nanotube functionalization takes place at the nanotube ends with the BeO bond displaying hydrogen-like bridge bonds. Moreover the nanotube semiconductor behavior remains unchanged. The polarity is high (it shows a transition from covalent to ionic) favoring solvatation. On the other hand, the work function low value suggests this to be a good candidate for the device fabrication. When the nanotube contains surface point defects the work function is reduced which provides excellent possibilities for the use of this material in the electronic industry. Copyright © 2013 Elsevier Inc. All rights reserved.

Investigation of surface potentials in reduced graphene oxide flake by Kelvin probe force microscopy

NASA Astrophysics Data System (ADS)

Negishi, Ryota; Takashima, Kai; Kobayashi, Yoshihiro

2018-06-01

The surface potential (SP) of reduced graphene oxide (rGO) flakes prepared by thermal treatments of GO under several conditions was analyzed by Kelvin probe force microscopy. The low-crystalline rGO flakes in which a significant amount of oxygen functional groups and structural defects remain have a much lower SP than mechanically exfoliated graphene free from oxygen and defects. On the other hand, the highly crystalline rGO flake after a thermal treatment for the efficient removal of oxygen functional groups and healing of structural defects except for domain boundary shows SP equivalent to that of the mechanically exfoliated graphene. These results indicate that the work function of rGO is sensitively modulated by oxygen functional groups and structural defects remaining after the thermal reduction process, but is not affected significantly by the domain boundary remaining after the healing of structural defects through the thermal treatment at high temperature.

Functional Characterization of a Novel Shape Memory Alloy

NASA Astrophysics Data System (ADS)

Collado, M.; Cabás, R.; San Juan, J.; López-Ferreño, I.

2014-07-01

A novel shape memory alloy (SMA) has been developed as an alternative to currently available alloys. This alloy, commercially known by its proprietary brand SMARQ, shows a higher working range of temperatures with respect to the SMA materials used until now in actuators, limited to environment temperatures below 90 °C. SMARQ is a high temperature SMA (HTSMA) based on a fully European material technology and production processes, which allows the manufacture of high quality products, with tuneable transformation temperatures up to 200 °C. Both, material and production processes have been evaluated for its use in space applications. A full characterization test campaign has been completed in order to obtain the material properties and check its suitability to be used as active material in space actuators. In order to perform the functional characterization of the material, it has been considered as the key element of a basic SMA actuator, consisting in the SMA wire and the mechanical and electrical interfaces. The functional tests presented in this work have been focused on the actuator behavior when heated by means of an electrical current. Alloy composition has been adjusted in order to match a transition temperature (As) of +145 °C, which satisfies the application requirements of operating temperatures in the range of -70 and +125 °C. Details of the tests and results of the characterization test campaign, focused in the material unique properties for their use in actuators, will be presented in this work. Some application examples in the field of space mechanisms and actuators, currently under development, will be summarized as part of this work, demonstrating the technology suitability as active material for space actuators.

Metronidazole as a protector of cells from electromagnetic radiation of extremely high frequencies

NASA Astrophysics Data System (ADS)

Kuznetsov, Pavel E.; Malinina, Ulia A.; Popyhova, Era B.; Rogacheva, Svetlana M.; Somov, Alexander U.

2006-08-01

It is well known that weak electromagnetic fields of extremely high frequencies cause significant modification of the functional status of biological objects of different levels of organization. The aim of the work was to study the combinatory effect of metronidazole - the drug form of 1-(2'hydroxiethil)-2-methil-5-nitroimidazole - and electromagnetic radiation of extremely high frequencies (52...75 GHz) on the hemolytic stability of erythrocytes and hemotaxis activity of Infusoria Paramecium caudatum.

Scale Refinement and Initial Evaluation of a Behavioral Health Function Measurement Tool for Work Disability Evaluation

PubMed Central

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

2014-01-01

Objectives To use item response theory (IRT) data simulations to construct and perform initial psychometric testing of a newly developed instrument, the Social Security Administration Behavioral Health Function (SSA-BH) instrument, that aims to assess behavioral health functioning relevant to the context of work. Design Cross-sectional survey followed by item response theory (IRT) calibration data simulations Setting Community Participants A sample of individuals applying for SSA disability benefits, claimants (N=1015), and a normative comparative sample of US adults (N=1000) Interventions None. Main Outcome Measure Social Security Administration Behavioral Health Function (SSA-BH) measurement instrument Results Item response theory analyses supported the unidimensionality of four SSA-BH scales: Mood and Emotions (35 items), Self-Efficacy (23 items), Social Interactions (6 items), and Behavioral Control (15 items). All SSA-BH scales demonstrated strong psychometric properties including reliability, accuracy, and breadth of coverage. High correlations of the simulated 5- or 10- item CATs with the full item bank indicated robust ability of the CAT approach to comprehensively characterize behavioral health function along four distinct dimensions. Conclusions Initial testing and evaluation of the SSA-BH instrument demonstrated good accuracy, reliability, and content coverage along all four scales. Behavioral function profiles of SSA claimants were generated and compared to age and sex matched norms along four scales: Mood and Emotions, Behavioral Control, Social Interactions, and Self-Efficacy. Utilizing the CAT based approach offers the ability to collect standardized, comprehensive functional information about claimants in an efficient way, which may prove useful in the context of the SSA’s work disability programs. PMID:23542404