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Sample records for achieves superior performance

  1. Achieving superior MEBES performance through the use of SPC programs and state-of-the-art facilities

    NASA Astrophysics Data System (ADS)

    Braz, Linda A.

    1993-06-01

    A MEBES III system can perform at levels that far exceed those published by the manufacturer. To achieve this, the photomask facility must be capable of maintaining extremely tight temperature controls. In addition, noise free power must be utilized and Class 10 cleanliness maintained. Through the use of a statistical process control (SPC) program generated at Etec, the MEBES performance can be monitored. Anomalies in system performance can be immediately identified and corrected without losing production masks. Impending system problems such as needed gun changes, gun centering, aperture changes, and charging of plates can be recognized and corrected before MEBES system performance would exceed our specifications. This paper also describes some of the unique facility designs/controls and demonstrated, through results, how these contribute to the MEBES performance.

  2. 28 CFR 2.60 - Superior program achievement.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 28 Judicial Administration 1 2010-07-01 2010-07-01 false Superior program achievement. 2.60 Section 2.60 Judicial Administration DEPARTMENT OF JUSTICE PAROLE, RELEASE, SUPERVISION AND RECOMMITMENT OF PRISONERS, YOUTH OFFENDERS, AND JUVENILE DELINQUENTS United States Code Prisoners and Parolees §...

  3. The Business Value of Superior Energy Performance

    SciTech Connect

    McKane, Aimee; Scheihing, Paul; Evans, Tracy; Glatt, Sandy; Meffert, William

    2015-08-04

    Industrial facilities participating in the U.S. Department of Energy’s (US DOE) Superior Energy Performance (SEP) program are finding that it provides them with significant business value. This value starts with the implementation of ISO 50001-Energy management system standard, which provides an internationally-relevant framework for integration of energy management into an organization’s business processes. The resulting structure emphasizes effective use of available data and supports continual improvement of energy performance. International relevance is particularly important for companies with a global presence or trading interests, providing them with access to supporting ISO standards and a growing body of certified companies representing the collective knowledge of communities of practice. This paper examines the business value of SEP, a voluntary program that builds on ISO 50001, inviting industry to demonstrate an even greater commitment through third-party verification of energy performance improvement to a specified level of achievement. Information from 28 facilities that have already achieved SEP certification will illustrate key findings concerning both the value and the challenges from SEP/ISO 50001 implementation. These include the facilities’ experience with implementation, internal and external value of third-party verification of energy performance improvement; attractive payback periods and the importance of SEP tools and guidance. US DOE is working to bring the program to scale, including the Enterprise-Wide Accelerator (SEP for multiple facilities in a company), the Ratepayer-Funded Program Accelerator (supporting tools for utilities and program administrators to include SEP in their program offerings), and expansion of the program to other sectors and industry supply chains.

  4. Bioinspired layered materials with superior mechanical performance.

    PubMed

    Cheng, Qunfeng; Jiang, Lei; Tang, Zhiyong

    2014-04-15

    Nature has inspired researchers to construct structures with ordered layers as candidates for new materials with high mechanical performance. As a prominent example, nacre, also known as mother of pearl, consists of a combination of inorganic plates (aragonite calcium carbonate, 95% by volume) and organic macromolecules (elastic biopolymer, 5% by volume) and shows a unique combination of strength and toughness. Investigations of its structure reveal that the hexagonal platelets of calcium carbonate and the amorphous biopolymer are alternatively assembled into the orderly layered structure. The delicate interface between the calcium carbonate and the biopolymer is well defined. Both the building blocks that make up these assembled layers and the interfaces between the inorganic and organic components contribute to the excellent mechanical property of natural nacre. In this Account, we summarize recent research from our group and from others on the design of bioinspired materials composed by layering various primitive materials. We focus particular attention on nanoscale carbon materials. Using several examples, we describe how the use of different combinations of layered materials leads to particular properties. Flattened double-walled carbon nanotubes (FDWCNTs) covalently cross-linked in a thermoset three-dimensional (3D) network produced the materials with the highest strength. The stiffest layered materials were generated from borate orthoester covalent bonding between adjacent graphene oxide (GO) nanosheets, and the toughest layered materials were fabricated with Al2O3 platelets and chitosan via hydrogen bonding. These new building blocks, such as FDWCNTs and GO, and the replication of the elaborate micro-/nanoscale interface of natural nacre have provided many options for developing new high performance artificial materials. The interface designs for bioinspired layered materials are generally categorized into (1) hydrogen bonding, (2) ionic bonding, and (3

  5. Advanced bit establishes superior performance in Ceuta field

    SciTech Connect

    Mensa-Wilmot, G.

    1999-11-01

    A new-generation polycrystalline diamond compact (PDC) bit is redefining operational efficiency and reducing drilling costs in the Ceuta field, in the Lago de Maracaibo area of Venezuela. Its unique cutting structure and advancements in PDC cutter technology have established superior performance in this challenging application. The paper describes the new-generation PDC bit, advanced technology PDC cutters, and performance. A table gives cost per foot evaluation.

  6. Type A Performance Standards and Goal Achievement.

    ERIC Educational Resources Information Center

    Ward, Clay H.

    Achievement striving is a central dimension of the Type A behavior pattern. To investigate the relationship between Type A behavior pattern, personal performance goals, and goal achievement on two general information tests, 126 undergraduates participated in a two-phase study. First, behavior patterns were assessed using the Framingham Type A…

  7. Assessing the Costs and Benefits of the Superior Energy Performance Program

    SciTech Connect

    Therkelsen, Peter; McKane, Aimee; Sabouini, Ridah; Evans, Tracy

    2013-07-01

    Industrial companies are seeking to manage energy consumption and costs, mitigate risks associated with energy, and introduce transparency into reports of their energy performance achievements. Forty industrial facilities are participating in the U.S. DOE supported Superior Energy Performance (SEP) program in which facilities implement an energy management system based on the ISO 50001 standard, and pursue third-party verification of their energy performance improvements. SEP certification provides industrial facilities recognition for implementing a consistent, rigorous, internationally recognized business process for continually improving energy performance and achievement of established energy performance improvement targets. This paper focuses on the business value of SEP and ISO 50001, providing an assessment of the costs and benefits associated with SEP implementation at nine SEP-certified facilities across a variety of industrial sectors. These cost-benefit analyses are part of the U.S. DOE?s contribution to the Global Superior Energy Performance (GSEP) partnership, a multi-country effort to demonstrate, using facility data, that energy management system implementation enables companies to improve their energy performance with a greater return on investment than business-as-usual (BAU) activity. To examine the business value of SEP certification, interviews were conducted with SEP-certified facilities. The costs of implementing the SEP program, including internal facility staff time, are described and a marginal payback of SEP certification has been determined. Additionally, more qualitative factors with regard to the business value and challenges related to SEP and ISO 50001 implementation are summarized.

  8. Interactions Between Teaching Performance and Student Achievement.

    ERIC Educational Resources Information Center

    Hsu, Yi-Ming; White, William F.

    There are two purposes for this study: first, to examine the relationship between college students' achievement and their ratings of instructors; second, to validate the two selected evaluation instruments that were designed specially for assessing teaching performance at the higher education level. Two evaluation inventories were selected for…

  9. Capturing Naturally Occurring Superior Performance in the Laboratory: Translational Research on Expert Performance

    ERIC Educational Resources Information Center

    Ericsson, K. Anders; Williams, A. Mark

    2007-01-01

    One of the central challenges to studying highly skilled performance in the laboratory is methodological. It is necessary to develop standardized methods that allow investigators to make experts repeatedly reproduce their superior performance in the laboratory. The recent increase in demand for translational research has raised related issues of…

  10. Breakfast Intake and Composition is Associated with Superior Academic Achievement in Elementary School Children

    PubMed Central

    Ptomey, Lauren T.; Steger, Felicia L.; Schubert, Matthew M.; Lee, Jaehoon; Willis, Erik A.; Sullivan, Debra K.; Szabo-Reed, Amanda N.; Washburn, Richard A.; Donnelly, Joseph E.

    2016-01-01

    Objective To determine if breakfast consumption or content affects academic achievement measured by standardized tests. Methods Baseline data was collected in fall of 2011 from 698 students (50.5% female, age=7.5±0.6 yrs.) living in the state of Kansas. Academic achievement was assessed using three components from the Wechsler Individual Achievement Test (WIAT-III). Prior to taking the WIAT-III, participants completed a breakfast recall of all the foods and drinks consumed that morning, which was analyzed using NDS-R. WIAT-III scores were compared between breakfast and non-breakfast consumers in a sample (n=162) matched for age, sex, race, education level of both parents, household income, BMI, and cardiovascular fitness, and Pearson correlations were calculated from all breakfast eaters (n=617) between test performance and components of the breakfast. Results When compared to non-breakfast consumers, the breakfast consumers had significantly higher scores in all three WIAT-III components (all p<0.05). In breakfast consumers, servings of fruit juice were negatively correlated with reading comprehension and fluency standard score and mathematics standard score (both p<0.0001), and greater servings of whole grains were significantly related to higher scores in reading comprehension and fluency and mathematics (both p<0.05). Conclusion Both breakfast consumption and the content may be associated with improved standardized test performance in elementary school students. PMID:26697955

  11. Achieving High Performance Perovskite Solar Cells

    NASA Astrophysics Data System (ADS)

    Yang, Yang

    2015-03-01

    Recently, metal halide perovskite based solar cell with the characteristics of rather low raw materials cost, great potential for simple process and scalable production, and extreme high power conversion efficiency (PCE), have been highlighted as one of the most competitive technologies for next generation thin film photovoltaic (PV). In UCLA, we have realized an efficient pathway to achieve high performance pervoskite solar cells, where the findings are beneficial to this unique materials/devices system. Our recent progress lies in perovskite film formation, defect passivation, transport materials design, interface engineering with respect to high performance solar cell, as well as the exploration of its applications beyond photovoltaics. These achievements include: 1) development of vapor assisted solution process (VASP) and moisture assisted solution process, which produces perovskite film with improved conformity, high crystallinity, reduced recombination rate, and the resulting high performance; 2) examination of the defects property of perovskite materials, and demonstration of a self-induced passivation approach to reduce carrier recombination; 3) interface engineering based on design of the carrier transport materials and the electrodes, in combination with high quality perovskite film, which delivers 15 ~ 20% PCEs; 4) a novel integration of bulk heterojunction to perovskite solar cell to achieve better light harvest; 5) fabrication of inverted solar cell device with high efficiency and flexibility and 6) exploration the application of perovskite materials to photodetector. Further development in film, device architecture, and interfaces will lead to continuous improved perovskite solar cells and other organic-inorganic hybrid optoelectronics.

  12. Biological Motion Task Performance Predicts Superior Temporal Sulcus Activity

    ERIC Educational Resources Information Center

    Herrington, John D.; Nymberg, Charlotte; Schultz, Robert T.

    2011-01-01

    Numerous studies implicate superior temporal sulcus (STS) in the perception of human movement. More recent theories hold that STS is also involved in the "understanding" of human movement. However, almost no studies to date have associated STS function with observable variability in action understanding. The present study directly associated STS…

  13. The Effects of Attribution and Social Context on Superiors' Influence and Interaction with Low Performing Subordinates.

    ERIC Educational Resources Information Center

    Tjosvold, Dean

    1985-01-01

    Ninety managers interacted with low performing workers who demonstrated either insufficient ability or motivation. Results indicated that cooperative superiors expected mutual assistance, communicated supportively, and gave assistance. Superiors used threats and disliked low effort subordinates but wanted to work again with low ability…

  14. Achieving scale strategies for sustained competitive performance.

    PubMed

    Grube, Mark E; Gish, Ryan S; Tkach, Sasha N

    2008-05-01

    Growth to achieve scale requires the following strategic initiatives: Having a clear understanding of what the organization is and what it wants to become. Ensuring a structured and rigorous growth process. Leveraging size to achieve benefits of scale. Recognizing the importance of physicians, ambulatory care, and primary care. Establishing and maintaining accountability as growth occurs.

  15. Advanced Organic Permeable-Base Transistor with Superior Performance.

    PubMed

    Klinger, Markus P; Fischer, Axel; Kaschura, Felix; Scholz, Reinhard; Lüssem, Björn; Kheradmand-Boroujeni, Bahman; Ellinger, Frank; Kasemann, Daniel; Leo, Karl

    2015-12-16

    An optimized vertical organic permeable-base transistor (OPBT) competing with the best organic field-effect transistors in performance, while employing low-cost fabrication techniques, is presented. The OPBT stands out by its excellent power efficiency at the highest frequencies.

  16. Superior Ballistic Impact Resistance Achieved by the Co-Base Alloy Haynes 25

    NASA Technical Reports Server (NTRS)

    Hebsur, Mohan G.; Noebe, Ronald D.; Revilock, Duane M.

    2003-01-01

    The fan case in a jet engine is required to contain a fan blade in the rare event of a blade loss during operation. Because of its function, the fan case is the largest structural component in high-bypass-ratio turbofan engines used in commercial aircraft. Therefore, the use of lighter and stronger materials would be advantageous in most engines and is practically a necessity in the latest generation of high-bypass engines. Small panels, 7 in. wide by 7 in. long, of a number of metallic alloys were impact tested at room temperature with a 0.50-caliber blunt-nose titanium alloy projectile at the NASA Glenn Research Center (ref. 1). These metallic systems included several high-strength aluminum (Al) alloys, Al-based laminates, aluminum metal matrix composites (Al-MMCs), nickel-base superalloys (Inconel 718 and 625), several titanium (Ti) alloys in different heat treated conditions, 304L stainless steel, a stainless-steel-based laminate, and a high strength steel (Nitronic 60). It was determined that a simple Co-base alloy (Haynes 25) had the best impact resistance on an areal weight basis. Haynes 25 was at least 10 percent better than IMI 550, the best titanium alloy tested to date, and it was far superior to other metals, especially at higher impact velocities (greater than 1100 ft/sec). Because this material could be ideal for fan containment applications in supersonic aircraft as a replacement for titanium, impact tests were also conducted at 371 oC and compared with results from alloys tested at elevated temperature under previous programs (i.e., Inconel 718, Ti-6242, M-152, Timetal 21S, and Aeromet 100). Although cobalt-base alloys are used in some high-temperature engine applications, to our knowledge they are not used in any containment systems. Advantages of cobalt over titanium include lower cost, easier processing, better high-temperature strength, and no fire hazard if tip rub occurs. Future plans include testing of lightweight sandwich panels with Haynes

  17. Dobutamine stress echo is superior to exercise stress testing in achieving target heart rate among patients on beta blockers.

    PubMed

    Sabbath, Adam; Pack, Michael; Markiewicz, Richard; John, Jooby; Gaballa, Mohamed; Goldman, Steven; Thai, Hoang

    2005-01-01

    Published guidelines recommend continuing beta-adrenergic receptor blockade in patients undergoing stress testing. We evaluated the role of pharmacological versus exercise stress testing in achieving target heart rate (THR) among patients on beta-adrenergic blockade. We compared data from 140 patients who underwent dobutamine stress echo (DSE) and 143 patients who underwent exercise treadmill testing (ETT). In both groups, beta-adrenergic blocker was continued at the time of stress testing. Overall, patients undergoing DSE achieved THR more frequently than ETT. With beta-adrenergic blockade, DSE patients met THR more frequently than ETT patients (p < 0.001). Without beta-adrenergic blockade, there was no difference between either modality in achieving THR. In both DSE and ETT patients, absence of beta-adrenergic blockade increased the odds of achieving THR [odds ratio (OR): 2.46, p = 0.042 and OR: 7.44, p < 0.001, respectively]. Atropine use with DSE increased the odds of achieving THR (OR: 3.76, p = 0.006). In conclusion, pharmacological stress testing appears to be superior to exercise stress testing in achieving THR among patients on beta-adrenergic blockade.

  18. Superior austempered ductile iron (ADI) properties achieved by prior hot isostatic pressing (HIP)

    SciTech Connect

    LaGoy, J.L.; Widmer, R.; Zick, D.H.

    1996-12-31

    Ductile iron obtained from different foundries and cast by dissimilar methods has been successfully hot isostatically pressed (HIPed) before austempering to achieve substantially higher ductilities, without significant detriment to other properties, than those reached by austempering along. HIP was attempted to solve different mechanical deficiencies in austempered ductile iron (ADI) such as the lack of ductility in higher strength grades, inconsistent mechanical properties, and service life limitations. A variety of HIP temperatures were analyzed from near the austenitizing region up to within 56 C (100 F) of the melting point of ductile iron. Microporosity was eliminated by HIP at all temperatures, and subsequent austempering revealed a uniform ADI microstructure. HIP proved successful with both unencapsulated castings and those enclosed within steel canisters. Additional benefits caused by HIP processing of ductile iron castings without the austempering treatment include a significant decrease in mechanical property data scatter, high hardness at reasonable ductility levels, and a substantially reduced scrap rate.

  19. Dealloying-driven nanoporous palladium with superior electrochemical actuation performance

    NASA Astrophysics Data System (ADS)

    Zhang, Jie; Bai, Qingguo; Zhang, Zhonghua

    2016-03-01

    Metal-hydrogen (in particular, Pd-H) interactions have been receiving considerable attention over the past 150 years within the scope of hydrogen storage, catalytic hydrogenation, hydrogen embrittlement and hydrogen-induced interfacial failure. Here, for the first time, we show that the coupling of hydrogen adsorption and absorption could trigger giant reversible strain in bulk nanoporous Pd (np-Pd) in a weakly adsorbed NaF electrolyte. The bulk np-Pd with a hierarchically porous structure and a ligament/channel size of ~10 nm was fabricated using a dealloying strategy with compositional/structural design of the precursor. The np-Pd actuator exhibits a giant reversible strain of up to 3.28% (stroke of 137.8 μm), which is a 252% enhancement in comparison to the state-of-the-art value of 1.3% in np-AuPt. The strain rate (~10-5 s-1) of np-Pd is two orders of magnitude higher than that of current metallic actuators. Moreover, the volume-/mass-specific strain energy density (10.71 MJ m-3/3811 J kg-1) of np-Pd reaches the highest level compared with that of previously reported actuator materials. The outstanding actuation performance of np-Pd could be attributed to the coupling of hydrogen adsorption/absorption and its unique hierarchically nanoporous structure. Our findings provide valuable information for the design of novel high-performance metallic actuators.Metal-hydrogen (in particular, Pd-H) interactions have been receiving considerable attention over the past 150 years within the scope of hydrogen storage, catalytic hydrogenation, hydrogen embrittlement and hydrogen-induced interfacial failure. Here, for the first time, we show that the coupling of hydrogen adsorption and absorption could trigger giant reversible strain in bulk nanoporous Pd (np-Pd) in a weakly adsorbed NaF electrolyte. The bulk np-Pd with a hierarchically porous structure and a ligament/channel size of ~10 nm was fabricated using a dealloying strategy with compositional/structural design of the

  20. Plasma performance in JET: Achievements and projections

    SciTech Connect

    Gibson, A.

    1988-01-01

    An account is given of recent experimental advances on JET, especially as they relate to fusion performance. Scaling relations are used to identify the critical parameters which need to be optimized to secure the best fusion performance. Finally the established best performance of JET is used as a base to project the performance to be expected in future D-T operation. 13 refs., 20 figs., 6 tabs.

  1. Achievement Components of Stanford-Binet Performance.

    ERIC Educational Resources Information Center

    Washington, Ernest D.; And Others

    A curriculum was devised by working backward from Stanford-Binet items to specification of a universe of content for which the Stanford-Binet could serve as a content-valid achievement test. It was reasoned that this curriculum should home. This curriculum was tested on 20 4-year-old disadvantaged children in Champaign-Urbana, Illinois. The…

  2. Development of an Enhanced Payback Function for the Superior Energy Performance Program

    SciTech Connect

    Therkelsen, Peter; Rao, Prakash; McKane, Aimee; Sabouni, Ridah; Sheihing, Paul

    2015-08-03

    The U.S. DOE Superior Energy Performance (SEP) program provides recognition to industrial and commercial facilities that achieve certification to the ISO 50001 energy management system standard and third party verification of energy performance improvements. Over 50 industrial facilities are participating and 28 facilities have been certified in the SEP program. These facilities find value in the robust, data driven energy performance improvement result that the SEP program delivers. Previous analysis of SEP certified facility data demonstrated the cost effectiveness of SEP and identified internal staff time to be the largest cost component related to SEP implementation and certification. This paper analyzes previously reported and newly collected data of costs and benefits associated with the implementation of an ISO 50001 and SEP certification. By disaggregating “sunk energy management system (EnMS) labor costs”, this analysis results in a more accurate and detailed understanding of the costs and benefits of SEP participation. SEP is shown to significantly improve and sustain energy performance and energy cost savings, resulting in a highly attractive return on investment. To illustrate these results, a payback function has been developed and is presented. On average facilities with annual energy spend greater than $2M can expect to implement SEP with a payback of less than 1.5 years. Finally, this paper also observes and details decreasing facility costs associated with implementing ISO 50001 and certifying to the SEP program, as the program has improved from pilot, to demonstration, to full launch.

  3. The advantage of a decreasing right-hand superiority: the influence of laterality on a selected musical skill (sight reading achievement).

    PubMed

    Kopiez, Reinhard; Galley, Niels; Lee, Ji In

    2006-01-01

    In this study, the unrehearsed performance of music, known as 'sight reading', is used as a model to examine the influence of motoric laterality on highly challenging musical performance skills. As expertise research has shown, differences in this skill can be partially explained by factors such as accumulated practise and an early start to training. However, up until now, neurobiological factors that may influence highly demanding instrumental performance have been widely neglected. In an experiment with 52 piano students at a German university music department, we could show that the most challenging musical skill, sight reading (which is characterized by extreme demands on the performer's real time information processing), is positively correlated with decreasing right-hand superiority of performers. Laterality was measured by the differences between left and right-hand performance in a speed tapping task. SR achievement was measured using an accompanying task paradigm. An overall superiority of 22% for non-right-handed pianists was found. This effect is gender-related and stronger in non-right-handed males (r(24) = -0.49, p<0.05) than in non-right-handed females (r(28) = -0.16, p>0.05). We conclude that non-right-handed motoric laterality is associated with neurobiological advantages required for sight reading, an extremely demanding musical subskill.

  4. The advantage of a decreasing right-hand superiority: the influence of laterality on a selected musical skill (sight reading achievement).

    PubMed

    Kopiez, Reinhard; Galley, Niels; Lee, Ji In

    2006-01-01

    In this study, the unrehearsed performance of music, known as 'sight reading', is used as a model to examine the influence of motoric laterality on highly challenging musical performance skills. As expertise research has shown, differences in this skill can be partially explained by factors such as accumulated practise and an early start to training. However, up until now, neurobiological factors that may influence highly demanding instrumental performance have been widely neglected. In an experiment with 52 piano students at a German university music department, we could show that the most challenging musical skill, sight reading (which is characterized by extreme demands on the performer's real time information processing), is positively correlated with decreasing right-hand superiority of performers. Laterality was measured by the differences between left and right-hand performance in a speed tapping task. SR achievement was measured using an accompanying task paradigm. An overall superiority of 22% for non-right-handed pianists was found. This effect is gender-related and stronger in non-right-handed males (r(24) = -0.49, p<0.05) than in non-right-handed females (r(28) = -0.16, p>0.05). We conclude that non-right-handed motoric laterality is associated with neurobiological advantages required for sight reading, an extremely demanding musical subskill. PMID:16321405

  5. Performance improvements from imagery: evidence that internal visual imagery is superior to external visual imagery for slalom performance

    PubMed Central

    Callow, Nichola; Roberts, Ross; Hardy, Lew; Jiang, Dan; Edwards, Martin Gareth

    2013-01-01

    We report three experiments investigating the hypothesis that use of internal visual imagery (IVI) would be superior to external visual imagery (EVI) for the performance of different slalom-based motor tasks. In Experiment 1, three groups of participants (IVI, EVI, and a control group) performed a driving-simulation slalom task. The IVI group achieved significantly quicker lap times than EVI and the control group. In Experiment 2, participants performed a downhill running slalom task under both IVI and EVI conditions. Performance was again quickest in the IVI compared to EVI condition, with no differences in accuracy. Experiment 3 used the same group design as Experiment 1, but with participants performing a downhill ski-slalom task. Results revealed the IVI group to be significantly more accurate than the control group, with no significant differences in time taken to complete the task. These results support the beneficial effects of IVI for slalom-based tasks, and significantly advances our knowledge related to the differential effects of visual imagery perspectives on motor performance. PMID:24155710

  6. Superior Chemical Sensing Performance of Black Phosphorus: Comparison with MoS2 and Graphene.

    PubMed

    Cho, Soo-Yeon; Lee, Youhan; Koh, Hyeong-Jun; Jung, Hyunju; Kim, Jong-Seon; Yoo, Hae-Wook; Kim, Jihan; Jung, Hee-Tae

    2016-08-01

    Superior chemical sensing performance of black phosphorus (BP) is demonstrated by comparison with MoS2 and graphene. Dynamic sensing measurements of multichannel detection show that BP displays highly sensitive, selective, and fast-responsive NO2 sensing performance compared to the other representative 2D sensing materials. PMID:27283330

  7. Superior performance with sCMOS over EMCCD in super-resolution optical fluctuation imaging

    NASA Astrophysics Data System (ADS)

    Chen, Xuanze; Zeng, Zhiping; Li, Rongqin; Xue, Boxin; Xi, Peng; Sun, Yujie

    2016-06-01

    Super-resolution optical fluctuation imaging (SOFI) is a fast and low-cost live-cell optical nanoscopy for extracting subdiffraction information from the statistics of fluorescence intensity fluctuation. As SOFI is based on the fluctuation statistics, rather than the detection of single molecules, it poses unique requirements for imaging detectors, which still lack a systematic evaluation. Here, we analyze the influences of pixel sizes, frame rates, noise levels, and different gains in SOFI with simulations and experimental tests. Our analysis shows that the smaller pixel size and faster readout speed of scientific-grade complementary metal oxide semiconductor (sCMOS) enables SOFI to achieve high spatiotemporal resolution with a large field-of-view, which is especially beneficial for live-cell super-resolution imaging. Overall, as the performance of SOFI is relatively insensitive to the signal-to-noise ratio (SNR), the gain in pixel size and readout speed exceeds the loss in SNR, indicating sCMOS is superior to electron multiplying charge coupled device in context to SOFI in many cases. Super-resolution imaging of cellular microtubule structures with high-order SOFI is experimentally demonstrated at large field-of-view, taking advantage of the large pixel number and fast frame rate of sCMOS cameras.

  8. Using the 2 x 2 Framework of Achievement Goals to Predict Achievement Emotions and Academic Performance

    ERIC Educational Resources Information Center

    Putwain, David W.; Sander, Paul; Larkin, Derek

    2013-01-01

    Previous work has established how achievement emotions are related to the trichotomous model of achievement goals, and how they predict academic performance. In our study we examine relations using an additional, mastery-avoidance goal, and whether outcome-focused emotions are predicted by mastery as well as performance goals. Results showed that…

  9. Achievement Goals and Achievement Emotions: Testing a Model of Their Joint Relations with Academic Performance

    ERIC Educational Resources Information Center

    Pekrun, Reinhard; Elliot, Andrew J.; Maier, Markus A.

    2009-01-01

    The authors propose a theoretical model linking achievement goals and achievement emotions to academic performance. This model was tested in a prospective study with undergraduates (N = 213), using exam-specific assessments of both goals and emotions as predictors of exam performance in an introductory-level psychology course. The findings were…

  10. Revising superior planning performance in chess players: the impact of time restriction and motivation aspects.

    PubMed

    Unterrainer, Josef Martin; Kaller, Christoph Philipp; Leonhart, Rainer; Rahm, Benjamin

    2011-01-01

    In a previous study (Unterrainer, Kaller, Halsband, & Rahm, 2006), chess players outperformed non-chess players in the Tower of London planning task but exhibited disproportionately longer processing times. This pattern of results raises the question of whether chess players' planning capabilities are superior or whether the results reflect differences in the speed-accuracy trade-off between the groups, possibly attributable to sports motivation. The present study was designed to disambiguate these alternative suggestions by implementing various constraints on planning time and by assessing self-reported motivation. In contrast to the previous study, chess players' performance was not superior, independently of whether problems had to be solved with (Experiment 1) or without (Experiment 2) time limits. As expected, chess players reported higher overall trait and state motivation scores across both experiments. These findings revise the notion of superior planning performance in chess players. In consequence, they do not conform with the assumption of a general transfer of chess-related planning expertise to other cognitive domains, instead suggesting that superior performance may be possible only under specific circumstances such as receiving competitive instructions.

  11. Superior mechanical performance of highly porous, anisotropic nanocellulose-montmorillonite aerogels prepared by freeze casting.

    PubMed

    Donius, Amalie E; Liu, Andong; Berglund, Lars A; Wegst, Ulrike G K

    2014-09-01

    Directionally solidified nanofibrillated cellulose (NFC)-sodium-montmorillonite (MMT) composite aerogels with a honeycomb-like pore structure were compared with non-directionally frozen aerogels with equiaxed pore structure and identical composition and found to have superior functionalities. To explore structure-property correlations, three different aerogel compositions of 3wt% MMT, and 0.4wt%, 0.8wt%, and 1.2wt% NFC, respectively, were tested. Young׳s modulus, compressive strength and toughness were found to increase with increasing NFC content for both architectures. The modulus increased from 25.8kPa to 386kPa for the isotropic and from 2.13MPa to 3.86MPa for the anisotropic aerogels, the compressive yield strength increased from 3.3kPa to 18.0kPa for the isotropic and from 32.3kPa to 52.5kPa for the anisotropic aerogels, and the toughness increased from 6.3kJ/m(3) to 24.1kJ/m(3) for the isotropic and from 22.9kJ/m(3) to 46.2kJ/m(3) for the anisotropic aerogels. The great range of properties, which can be achieved through compositional as well as architectural variations, makes these aerogels highly attractive for a large range of applications, for which either a specific composition, or a particular pore morphology, or both are required. Finally, because NFC is flammable, gasification experiments were performed, which revealed that the inclusion of MMT increased the heat endurance and shape retention functions of the aerogels dramatically up to 800°C while the mechanical properties were retained up to 300°C. PMID:24905177

  12. The Role of Expertise Research and Human Factors in Capturing, Explaining, and Producing Superior Performance

    PubMed Central

    Charness, Neil; Tuffiash, Michael

    2009-01-01

    Objectives The goal of this article is to identify some of the major trends and findings in expertise research and their connections to human factors. Background Progress in the study of superior human performance has come from improved methods of measuring expertise and the development of better tools for revealing the mechanisms that support expert performance, such as protocol analysis and eye tracking. Methods We review some of the challenges of capturing superior human performance in the laboratory and the means by which the expert performance approach may overcome such challenges. We then discuss applications of the expert performance approach to a handful of domains that have long been of interest to human factors researchers. Results Experts depend heavily on domain-specific knowledge for superior performance, and such knowledge enables the expert to anticipate and prepare for future actions more efficiently. Training programs designed to focus learners’ attention on task-related knowledge and skills critical to expert performance have shown promise in facilitating skill acquisition among nonexperts and in reducing errors by experts on representative tasks. Conclusions Although significant challenges remain, there is encouraging progress in domains such as sports, aviation, and medicine in understanding some of the mechanisms underlying human expertise and in structuring training and tools to improve skilled performance. Applications Knowledge engineering techniques can capture expert knowledge and preserve it for organizations and for the development of expert systems. Understanding the mechanisms that underlie expert performance may provide insights into the structuring of better training programs for improving skill and in designing systems to support professional expertise. PMID:18689049

  13. Conservation and Achievement Test Performance among Fifth-Graders.

    ERIC Educational Resources Information Center

    Silliphant, Virginia M.; Cox, David L.

    The relationship between conservation and achievement is examined on specific tests and test items on the Stanford Achievement Test Battery used in the elementary years. Specifically, performance on two tests (Word Meaning and Arithmetic Concepts) were analyzed according to subjects level of thinking (concrete or formal) for total score,…

  14. Achieving Deeper Energy Savings in Federal Energy Performance Contracts

    DOE PAGES

    Shonder, John A.; Nasseri, Cyrus

    2015-01-01

    Legislation requires each agency of the US federal government to reduce the aggregate energy use index of its buildings by 30% by 2015, with respect to a 2003 baseline. The declining availability of appropriated funding means that energy performance contracting will be key to achieving this goal. Historically however, energy performance contracts have been able to reduce energy use by only about 20% over baseline. Achieving 30% energy reductions using performance contracting will require new approaches and a specific focus on achieving higher energy savings, both by ESCOs and by agencies. This paper describes some of the ways federal agenciesmore » are meeting this challenge, and presents results from the efforts of one agency the US General Services Administration -- to achieve deeper energy savings in conventional energy savings performance contracts.« less

  15. Achieving Deeper Energy Savings in Federal Energy Performance Contracts

    SciTech Connect

    Shonder, John A.; Nasseri, Cyrus

    2015-01-01

    Legislation requires each agency of the US federal government to reduce the aggregate energy use index of its buildings by 30% by 2015, with respect to a 2003 baseline. The declining availability of appropriated funding means that energy performance contracting will be key to achieving this goal. Historically however, energy performance contracts have been able to reduce energy use by only about 20% over baseline. Achieving 30% energy reductions using performance contracting will require new approaches and a specific focus on achieving higher energy savings, both by ESCOs and by agencies. This paper describes some of the ways federal agencies are meeting this challenge, and presents results from the efforts of one agency the US General Services Administration -- to achieve deeper energy savings in conventional energy savings performance contracts.

  16. Gender-Based Differential Item Performance in Mathematics Achievement Items.

    ERIC Educational Resources Information Center

    Doolittle, Allen E.

    A procedure for the detection of differential item performance (DIP) is used to investigate the relationships between characteristics of mathematics achievement items and gender differences in performance. Eight randomly equivalent samples of high school seniors were each given a unique form of the ACT Assessment Mathematics Usage Test (ACTM).…

  17. Patterns of Change in Psychological Variables Leading up to Competition in Superior Versus Inferior Performers.

    PubMed

    Boat, Ruth; Taylor, Ian M

    2015-06-01

    The study explored patterns of change in a number of potentially performance-related variables (i.e., fatigue, social support, self-efficacy, autonomous motivation, mental skills) during the lead-up to a competitive triathlon, and whether these patterns of change differed for relatively superior versus inferior performers. Forty-two triathletes completed an inventory measuring the study variables every other day during a 2-week period leading up to competition. Performance was assessed using participants' race time, and using a self-referenced relative score compared with personal best times. Multilevel growth curve analyses revealed significant differences in growth trajectories over the 2-week period in mental skills use, social support, and fatigue. The results provide novel insight into how athletes' fluctuating psychological state in the 2 weeks before competition may be crucial in determining performance. PMID:26265338

  18. Achieving High Performance on the i860 Microprocessor

    NASA Technical Reports Server (NTRS)

    Lee, King; Kutler, Paul (Technical Monitor)

    1998-01-01

    The i860 is a high performance microprocessor used in the Intel Touchstone project. This paper proposes a paradigm for programming the i860 that is modelled on the vector instructions of the Cray computers. Fortran callable assembler subroutines were written that mimic the concurrent vector instructions of the Cray. Cache takes the place of vector registers. Using this paradigm we have achieved twice the performance of compiled code on a traditional solve.

  19. The Effect of Contiguity on Informational Achievement and Psychomotor Performance.

    ERIC Educational Resources Information Center

    Hudson, Donald W.

    Using a randomized block design and involving the participation of 73 fifth, sixth, and seventh grade pupils, this study sought to ascertain the relative effects of traditional, varied and integrated contiguity on the achievement of information content and the performance of a psychomotor task. The informational content selected for the study…

  20. Effects of Motivational and Situational Variables on Achievement Performance.

    ERIC Educational Resources Information Center

    Boker, John R.; Games, Paul A.

    Problem-solving performance and goal-setting behavior were investigated in 156 undergraduates who, on Mehrabian's Achievement Scales, demonstrated either the motive to approach success or the motive to avoid failure. Different expectations of success or failure were induced by fictitious preperformance information. The degree of success or failure…

  1. Insights into collaborative separation process of photogenerated charges and superior performance of solar cells

    NASA Astrophysics Data System (ADS)

    Liu, Xiangyang; Wang, Shun; Zheng, Haiwu; Gu, Yuzong

    2016-07-01

    ZnO nanowires/Cu4Bi4S9 (ZnO/CBS) and ZnO nanowires/CBS-graphene nanoplates (ZnO/CBS-GNs), as well as two types of solar cells were prepared. The photovoltaic responses of CBS-GNs and ZnO/CBS-GNs can be improved with incorporation of GNs. The transient surface photovoltage (TPV) can provide detailed information on the separation and transport of photogenerated carriers. The multichannel separation process from the TPVs indicates that the macro-photoelectric signals can be attributed to the photogenerated charges separated at the interface of CBS/GNs, rather than CBS/ZnO. The multi-interfacial recombination is the major carrier loss, and the hole selective p-V2O5 can efficiently accelerate the charge extraction to the external circuit. The ZnO/CBS-GNs cell exhibits the superior performance, and the highest efficiency is 10.9%. With the adequate interfaces of CBS/GNs, GNs conductive network, energy level matching, etc., the excitons can easily diffuse to the interface of CBS/GNs, and the separated electrons and holes can be collected quickly, inducing the high photoelectric properties. Here, a facile strategy for solid state solar cells with superior performance presents a potential application.

  2. Nanotubes within transition metal silicate hollow spheres: Facile preparation and superior lithium storage performances

    SciTech Connect

    Zhang, Fan; An, Yongling; Zhai, Wei; Gao, Xueping; Feng, Jinkui; Ci, Lijie; Xiong, Shenglin

    2015-10-15

    Highlights: • The hollow Co{sub 2}SiO{sub 4}, MnSiO{sub 3} and CuSiO{sub 3} were successfully prepared by a facile hydrothermal method using SiO{sub 2} nanosphere. • The hollow Co{sub 2}SiO{sub 4}, MnSiO{sub 3} and CuSiO{sub 3} were tested as anode materials for lithium batteries. • The hollow Co{sub 2}SiO{sub 4}, MnSiO{sub 3} and CuSiO{sub 3} delivered superior electrochemical performance. • The lithium storage mechanism is probe via cyclic voltammetry and XPS. - Abstract: A series of transition metal silicate hollow spheres, including cobalt silicate (Co{sub 2}SiO{sub 4}), manganese silicate (MnSiO{sub 3}) and copper silicate (CuSiO{sub 3}.2H{sub 2}O, CuSiO{sub 3} as abbreviation in the text) were prepared via a simple and economic hydrothermal method by using silica spheres as chemical template. Time-dependent experiments confirmed that the resultants formed a novel type of hierarchical structure, hollow spheres assembled by numerous one-dimensional (1D) nanotubes building blocks. For the first time, the transition metal silicate hollow spheres were characterized as novel anode materials of Li-ion battery, which presented superior lithium storage capacities, cycle performance and rate performance. The 1D nanotubes assembly and hollow interior endow this kind of material facilitate fast lithium ion and electron transport and accommodate the big volume change during the conversion reactions. Our study shows that low-cost transition metal silicate with rationally designed nanostructures can be promising anode materials for high capacity lithium-ion battery.

  3. Metrics help rural hospitals achieve world-class performance.

    PubMed

    Goodspeed, Scott W

    2006-01-01

    This article describes the emerging trend of using metrics in rural hospitals to achieve world-class performance. This trend is a response to the fact that rural hospitals have small patient volumes yet must maintain a profit margin in order to fulfill their mission to the community. The conceptual idea for this article is based largely on Robert Kaplan and David Norton's Balanced Scorecard articles in the Harvard Business Review. The ideas also come from the experiences of the 60-plus rural hospitals that are using the Balanced Scorecard and their implementation of metrics to influence performance and behavior. It is indeed possible for rural hospitals to meet and exceed the unique needs of patients and physicians (customers), to achieve healthy profit margins, and to be the rural hospital of choice that employees are proud to work for. PMID:17518021

  4. Mechanical robust BiSbTe alloys with superior thermoelectric performance: A case study of stable hierarchical nanostructured thermoelectric materials

    NASA Astrophysics Data System (ADS)

    Su, Xianli; Zheng, Yun; Tang, Xinfeng; Uher, Ctirad; Tang's Group Team; Uher's Group Team

    2015-03-01

    Poor machinability and susceptibility to brittle fracture of commercial ingots often impose significant limitations on the manufacturing process and durability of thermoelectric devices. In this study, melt spinning combined with plasma activated sintering (MS-PAS) method is employed with commercial p-type zone-melted (ZM) ingots of Bi0.5Sb1.5Te3. This fast synthesis approach achieves hierarchical structures and in-situ nanoscale precipitates, resulting in the simultaneous improvement of thermoelectric performance and mechanical properties. Benefitting from a strong suppression of the lattice thermal conductivity, a peak ZT of 1.22 is achieved at 340 K in MS-PAS synthesized structures, representing about a 40% enhancement over that of ZM ingots. Moreover, MS-PAS specimens with hierarchical structures exhibit superior machinability and mechanical properties with an almost 30% enhancement in the fracture toughness, eightfold and a factor of six increase in the compressive and flexural strength respectively. We wish to acknowledge support from the National Basic Research Program of China (973 program) under Project 2013CB632502.

  5. Active vacuum brazing of CNT films to metal substrates for superior electron field emission performance

    NASA Astrophysics Data System (ADS)

    Longtin, Rémi; Sanchez-Valencia, Juan Ramon; Shorubalko, Ivan; Furrer, Roman; Hack, Erwin; Elsener, Hansrudolf; Gröning, Oliver; Greenwood, Paul; Rupesinghe, Nalin; Teo, Kenneth; Leinenbach, Christian; Gröning, Pierangelo

    2015-02-01

    The joining of macroscopic films of vertically aligned multiwalled carbon nanotubes (CNTs) to titanium substrates is demonstrated by active vacuum brazing at 820 °C with a Ag-Cu-Ti alloy and at 880 °C with a Cu-Sn-Ti-Zr alloy. The brazing methodology was elaborated in order to enable the production of highly electrically and thermally conductive CNT/metal substrate contacts. The interfacial electrical resistances of the joints were measured to be as low as 0.35 Ω. The improved interfacial transport properties in the brazed films lead to superior electron field-emission properties when compared to the as-grown films. An emission current of 150 μA was drawn from the brazed nanotubes at an applied electric field of 0.6 V μm-1. The improvement in electron field-emission is mainly attributed to the reduction of the contact resistance between the nanotubes and the substrate. The joints have high re-melting temperatures up to the solidus temperatures of the alloys; far greater than what is achievable with standard solders, thus expanding the application potential of CNT films to high-current and high-power applications where substantial frictional or resistive heating is expected.

  6. Concurrent engineering accelerates development of new slim hole bits to provide superior performance and reliability

    SciTech Connect

    Neal, P.A.

    1996-09-01

    The successful use of concurrent engineering to expedite new product development requires thoughtful selection of the project team, and clear performance objectives. Concurrent engineering, when properly implemented, can yield a superior product, with less development time, lower cost and greater product consistency. For critical applications, such as rock bits for slim hole drilling, product reliability is paramount. Slim hole bits require tighter process control to minimize variations that could impact bearing and seal clearances, bearing surface finishes, insert retention, and drilling efficiency of the bit. Greater durability and longer bit life are enhanced when the design and manufacturing processes are concurrently developed. The success of concurrently engineering a 4 3/4 inch slim hole insert bit for re-entry horizontal drilling had a direct impact on the cost of drilling, setting a world record in Canada for most footage drilled and reducing the cost per foot on a well in Hobbs, New Mexico by 40%. The total time required for the project to move from conception to successful bit run was 25% faster than traditional project development efforts. The paper will examine the development process of the 4 3/4 inch slim hole bit with emphasis on selecting a successful project team, establishing clear performance objectives and an analysis of field results from the initial field test which will demonstrate the attainment of the established objectives.

  7. Testing the performance of technical trading rules in the Chinese markets based on superior predictive test

    NASA Astrophysics Data System (ADS)

    Wang, Shan; Jiang, Zhi-Qiang; Li, Sai-Ping; Zhou, Wei-Xing

    2015-12-01

    Technical trading rules have a long history of being used by practitioners in financial markets. The profitable ability and efficiency of technical trading rules are yet controversial. In this paper, we test the performance of more than seven thousand traditional technical trading rules on the Shanghai Securities Composite Index (SSCI) from May 21, 1992 through June 30, 2013 and China Securities Index 300 (CSI 300) from April 8, 2005 through June 30, 2013 to check whether an effective trading strategy could be found by using the performance measurements based on the return and Sharpe ratio. To correct for the influence of the data-snooping effect, we adopt the Superior Predictive Ability test to evaluate if there exists a trading rule that can significantly outperform the benchmark. The result shows that for SSCI, technical trading rules offer significant profitability, while for CSI 300, this ability is lost. We further partition the SSCI into two sub-series and find that the efficiency of technical trading in sub-series, which have exactly the same spanning period as that of CSI 300, is severely weakened. By testing the trading rules on both indexes with a five-year moving window, we find that during the financial bubble from 2005 to 2007, the effectiveness of technical trading rules is greatly improved. This is consistent with the predictive ability of technical trading rules which appears when the market is less efficient.

  8. Carbon-coated lithium titanium phosphate nanoporous microplates with superior electrochemical performance

    NASA Astrophysics Data System (ADS)

    Huang, Zhifeng; Liu, Li; Zhou, Qian; Tan, Jinli; Yan, Zichao; Xia, Dongdong; Shu, Hongbo; Yang, Xiukang; Wang, Xianyou

    2015-10-01

    In this study, we report a facile method to synthesize carbon-coated LiTi2(PO4)3 nanoporous microplates (LTP/C MPs) using ethylenediamine as the chelating agent and carbon source. The as-prepared LTP/C MPs with thickness of 0.4 μm consist of interconnected nanosized particles embedded in nano-thickness carbon layer and well-dispersed nanopores. The carbon layer significantly improves the electrochemical performance of LiTi2(PO4)3 microplates. LTP/C MPs deliver a reversible capacity of 121 mAh g-1 at 0.2C (1C = 138 mAh g-1) and show a remarkable capacity retention of 94.2% over 100 cycles when matched with Li metal counter electrode. It also presents excellent electrochemical properties as anode material for aqueous rechargeable lithium batteries (ARLBs). LTP/C MPs//LiMn2O4 ARLB shows a high discharge capacity of 76 mAh g-1 at 20 mA g-1 and superior rate capability. The results suggest a practical stratagem to develop a novel composite in which the carbon is coated with LiTi2(PO4)3 nanoporous microplates, which can become one of the promising electrode materials for both non-aqueous and aqueous lithium ion batteries.

  9. Right Occipital Cortex Activation Correlates with Superior Odor Processing Performance in the Early Blind

    PubMed Central

    Grandin, Cécile B.; Dricot, Laurence; Plaza, Paula; Lerens, Elodie; Rombaux, Philippe; De Volder, Anne G.

    2013-01-01

    Using functional magnetic resonance imaging (fMRI) in ten early blind humans, we found robust occipital activation during two odor-processing tasks (discrimination or categorization of fruit and flower odors), as well as during control auditory-verbal conditions (discrimination or categorization of fruit and flower names). We also found evidence for reorganization and specialization of the ventral part of the occipital cortex, with dissociation according to stimulus modality: the right fusiform gyrus was most activated during olfactory conditions while part of the left ventral lateral occipital complex showed a preference for auditory-verbal processing. Only little occipital activation was found in sighted subjects, but the same right-olfactory/left-auditory-verbal hemispheric lateralization was found overall in their brain. This difference between the groups was mirrored by superior performance of the blind in various odor-processing tasks. Moreover, the level of right fusiform gyrus activation during the olfactory conditions was highly correlated with individual scores in a variety of odor recognition tests, indicating that the additional occipital activation may play a functional role in odor processing. PMID:23967263

  10. T-gate aligned nanotube radio frequency transistors and circuits with superior performance.

    PubMed

    Che, Yuchi; Lin, Yung-Chen; Kim, Pyojae; Zhou, Chongwu

    2013-05-28

    In this paper, we applied self-aligned T-gate design to aligned carbon nanotube array transistors and achieved an extrinsic current-gain cutoff frequency (ft) of 25 GHz, which is the best on-chip performance for nanotube radio frequency (RF) transistors reported to date. Meanwhile, an intrinsic current-gain cutoff frequency up to 102 GHz is obtained, comparable to the best value reported for nanotube RF transistors. Armed with the excellent extrinsic RF performance, we performed both single-tone and two-tone measurements for aligned nanotube transistors at a frequency up to 8 GHz. Furthermore, we utilized T-gate aligned nanotube transistors to construct mixing and frequency doubling analog circuits operated in gigahertz frequency regime. Our results confirm the great potential of nanotube-based circuit applications and indicate that nanotube transistors are promising building blocks in high-frequency electronics.

  11. Phthalonitrile-Based Carbon Foam with High Specific Mechanical Strength and Superior Electromagnetic Interference Shielding Performance.

    PubMed

    Zhang, Liying; Liu, Ming; Roy, Sunanda; Chu, Eng Kee; See, Kye Yak; Hu, Xiao

    2016-03-23

    Electromagnetic interference (EMI) performance materials are urgently needed to relieve the increasing stress over electromagnetic pollution problems arising from the growing demand for electronic and electrical devices. In this work, a novel ultralight (0.15 g/cm(3)) carbon foam was prepared by direct carbonization of phthalonitrile (PN)-based polymer foam aiming to simultaneously achieve high EMI shielding effectiveness (SE) and deliver effective weight reduction without detrimental reduction of the mechanical properties. The carbon foam prepared by this method had specific compressive strength of ∼6.0 MPa·cm(3)/g. High EMI SE of ∼51.2 dB was achieved, contributed by its intrinsic nitrogen-containing structure (3.3 wt% of nitrogen atoms). The primary EMI shielding mechanism of such carbon foam was determined to be absorption. Moreover, the carbon foams showed excellent specific EMI SE of 341.1 dB·cm(3)/g, which was at least 2 times higher than most of the reported material. The remarkable EMI shielding performance combined with high specific compressive strength indicated that the carbon foam could be considered as a low-density and high-performance EMI shielding material for use in areas where mechanical integrity is desired.

  12. Assessment of physician performance in Alberta: the Physician Achievement Review

    PubMed Central

    Hall, W; Violato, C; Lewkonia, R; Lockyer, J; Fidler, H; Toews, J; Jennett, P; Donoff, M; Moores, D

    1999-01-01

    The College of Physicians and Surgeons of Alberta, in collaboration with the Universities of Calgary and Alberta, has developed a program to routinely assess the performance of physicians, intended primarily for quality improvement in medical practice. The Physician Achievement Review (PAR) provides a multidimensional view of performance through structured feedback to physicians. The program will also provide a new mechanism for identifying physicians for whom more detailed assessment of practice performance or medical competence may be needed. Questionnaires were created to assess an array of performance attributes, and then appropriate assessors were designated--the physician himself or herself (self-evaluation), patients, medical peers, consultants and referring physicians, and non-physician coworkers. A pilot study with 308 physician volunteers was used to evaluate the psychometric and statistical properties of the questionnaires and to develop operating policies. The pilot surveys showed good statistical validity and technical reliability of the PAR questionnaires. For only 28 (9.1%) of the physicians were the PAR results more than one standard deviation from the peer group means for 3 or more of the 5 major domains of assessment (self, patients, peers, consultants and coworkers). In post-survey feedback, two-thirds of the physicians indicated that they were considering or had implemented changes to their medical practice on the basis of their PAR data. The estimated operating cost of the PAR program is approximately $200 per physician. In February 1999, on the basis of the operating experience and the results of the pilot survey, the College of Physicians and Surgeons of Alberta implemented this innovative program, in which all Alberta physicians will be required to participate every 5 years. PMID:10420867

  13. Electrochemical activation of carbon cloth in aqueous inorganic salt solution for superior capacitive performance

    NASA Astrophysics Data System (ADS)

    Ye, Dong; Yu, Yao; Tang, Jie; Liu, Lin; Wu, Yue

    2016-05-01

    Carbon cloth (CC) is an inexpensive and highly conductive textile with excellent mechanical flexibility and strength; it holds great promise as an electrode material for flexible supercapacitors. However, pristine CC has such a low surface area and poor electrochemical activity that the energy storage capability is usually very poor. Herein, we report a green method, two-step electrochemical activation in an aqueous solution of inorganic salts, to significantly enhance the capacitance of CC for supercapacitor application. Micro-cracks, exfoliated carbon fiber shells, and oxygen-containing functional groups (OFGs) were introduced onto the surface of the carbon filament. This resulted in an enhancement of over two orders of magnitude in capacitance compared to that of the bare CC electrode, reaching up to a maximum areal capacitance of 505.5 mF cm-2 at the current density of 6 mA cm-2 in aqueous H2SO4 electrolyte. Electrochemical reduction of CC electrodes led to the removal of most electrochemically unstable surface OFGs, resulting in superior charging/discharging rate capability and excellent cycling stability. Although the activated CC electrode contained a high-level of surface oxygen functional groups (~15 at%), it still exhibited a remarkable charging-discharging rate capability, retaining ~88% of the capacitance when the charging rate increased from 6 to 48 mA cm-2. Moreover, the activated CC electrode exhibited excellent cycling stability with ~97% capacitance remaining after 10 000 cycles at a current density of 24 mA cm-2. A symmetrical supercapacitor based on the activated CC exhibited an ideal capacitive behavior and fast charge-discharge properties. Such a simple, environment-friendly, and cost-effective strategy to activate CC shows great potential in the fabrication of high-performance flexible supercapacitors.Carbon cloth (CC) is an inexpensive and highly conductive textile with excellent mechanical flexibility and strength; it holds great promise as

  14. Science Achievement for All: Improving Science Performance and Closing Achievement Gaps

    ERIC Educational Resources Information Center

    Jackson, Julie K.; Ash, Gwynne

    2012-01-01

    This article addresses the serious and growing need to improve science instruction and science achievement for all students. We will describe the results of a 3-year study that transformed science instruction and student achievement at two high-poverty ethnically diverse public elementary schools in Texas. The school-wide intervention included…

  15. Achieving fast timing performance with multiplexed SiPMs

    NASA Astrophysics Data System (ADS)

    Bieniosek, M. F.; Cates, J. W.; Levin, C. S.

    2016-04-01

    Using time of flight (ToF) measurements for positron emission tomography (PET) is an attractive avenue for increasing the signal to noise (SNR) ratio of PET images. However, achieving excellent time resolution required for high SNR gain using silicon photomultipliers (SiPM) requires many resource heavy high bandwidth readout channels. A method of multiplexing many SiPM signals into a single electronic channel would greatly simplify ToF PET systems. However, multiplexing SiPMs degrades time resolution because of added dark counts and signal shaping. In this work the relative contribution of dark counts and signal shaping to timing degradation is simulated and a baseline correction technique to mitigate the effect of multiplexing on the time resolution of analog SiPMs is simulated and experimentally verified. A charge sharing network for multiplexing is proposed and tested. Results show a full width at half maximum (FWHM) coincidence time resolution of 232+/- 2 ps for a single 3 mm  ×  3 mm  ×  20 mm LYSO scintillation crystals coupled to an array of sixteen 3 mm  ×  3 mm SiPMs that are multiplexed to a single timing channel (in addition to 4 position channels). A 4× 4 array of 3 mm  ×  3 mm  ×  20 mm LFS crystals showed an average FWHM coincidence time resolution of 278+/- 7 ps using the same timing scheme. All experiments were performed at room temperature with no thermal regulation. These results show that excellent time resolution for ToF can be achieved with a highly multiplexed analog SiPM readout.

  16. Non-Superior Disembedding Performance in Children with High-Functioning Autism and Its Cognitive Style Account

    ERIC Educational Resources Information Center

    Chen, Fei; Lemonnier, Eric; Lazartigues, Alain; Planche, Pascale

    2008-01-01

    Some early studies showed a superior disembedding performance in autistic people while other studies found no difference between autistic and controls. The present study aimed to assess such disembedding ability in 14 boys with high-functioning autism (HFA) and 14 chronological age and non-verbal IQ matched typically developed boys using an…

  17. Science Achievement for All: Improving Science Performance and Closing Achievement Gaps

    NASA Astrophysics Data System (ADS)

    Jackson, Julie K.; Ash, Gwynne

    2012-11-01

    This article addresses the serious and growing need to improve science instruction and science achievement for all students. We will describe the results of a 3-year study that transformed science instruction and student achievement at two high-poverty ethnically diverse public elementary schools in Texas. The school-wide intervention included purposeful planning, inquiry science instruction, and contextually rich academic science vocabulary development. In combination, these instructional practices rapidly improved student-science learning outcomes and narrowed achievement gaps across diverse student populations.

  18. Separation of Performance-Approach and Performance-Avoidance Achievement Goals : A Broader Analysis

    ERIC Educational Resources Information Center

    Murayama, Kou; Elliot, Andrew J.; Yamagata, Shinji

    2011-01-01

    In the literature on achievement goals, performance-approach goals (striving to do better than others) and performance-avoidance goals (striving to avoid doing worse than others) tend to exhibit a moderate to high correlation, raising questions about whether the 2 goals represent distinct constructs. In the current article, we sought to examine…

  19. Enhancing reproductive performance in dairy buffalo: major constraints and achievements.

    PubMed

    Nanda, A S; Brar, P S; Prabhakar, S

    2003-01-01

    Buffalo are of high economic importance for farmers in several developing countries but reproductive performance is poor. A large proportion of heifers attain puberty at 3-5 years of age. A good quality diet supplemented with extra nutrients reduces the age of puberty, whereas the effects of administration of exogenous GnRH or equine chorionic gonadotrophin (eCG) are equivocal. The incidence of anoestrus in buffalo ranges from 20 to 80% depending on season. Most buffalo cease ovarian cyclicity during hot summers probably due to the combined effects of nutrition, environment and management. Keeping buffalo cool by wallowing, water sprinklers or shade improves fertility. Supplementary feeding with Urea Molasses Multi-nutrient Blocks (UMMB) for 60 days before calving enhances the early onset of postpartum oestrus. Regular UMMB supplementation also improves pregnancy rates in anoestrous non-pregnant buffalo. Prepartum vaginal prolapse is hereditary and eradication can be achieved by genetic selective breeding programmes. Treatment with calcium, phosphorus and progesterone gives only transient relief to clinical cases. Uterine torsion is the most common cause of dystocia (70%). Deployment of Sharma's detorsion method and anti-stress measures increase survival rates in cases presented within 36 h. In conclusion, greater understanding about the effects of better year-round nutrition, improved management and markers for logical breeding programmes are essential to curtail the incidence of the reproductive disorders that reduce buffalo fertility.

  20. Factors Related to How Superiors Establish Goals and Review Performance for Their Subordinates.

    ERIC Educational Resources Information Center

    Carroll, Stephen J., Jr.; And Others

    The objective of the study was to identify the characteristics of the superior, the subordinate, and the situation which were related to the manner in which the "Management by Objectives" (MBO) process is carried out. Data collected from 112 managers in a national industrial firm was used in the analysis. Previous research with this data had…

  1. Superior Performance of Aptamer in Tumor Penetration over Antibody: Implication of Aptamer-Based Theranostics in Solid Tumors

    PubMed Central

    Xiang, Dongxi; Zheng, Conglong; Zhou, Shu-Feng; Qiao, Shuxi; Tran, Phuong Ha-Lien; Pu, Chunwen; Li, Yong; Kong, Lingxue; Kouzani, Abbas Z.; Lin, Jia; Liu, Ke; Li, Lianhong; Shigdar, Sarah; Duan, Wei

    2015-01-01

    Insufficient penetration of therapeutic agents into tumor tissues results in inadequate drug distribution and lower intracellular concentration of drugs, leading to the increase of drug resistance and resultant failure of cancer treatment. Targeted drug delivery to solid tumors followed by complete drug penetration and durable retention will significantly improve clinical outcomes of cancer therapy. Monoclonal antibodies have been commonly used in clinic for cancer treatment, but their limitation of penetrating into tumor tissues still remains because of their large size. Aptamers, as “chemical antibodies”, are 15-20 times smaller than antibodies. To explore whether aptamers are superior to antibodies in terms of tumor penetration, we carried out the first comprehensive study to compare the performance of an EpCAM aptamer with an EpCAM antibody in theranostic applications. Penetration and retention were studied in in vitro three-dimensional tumorspheres, in vivo live animal imaging and mouse colorectal cancer xenograft model. We found that the EpCAM aptamer can not only effectively penetrate into the tumorsphere cores but can also be retained by tumor sphere cells for at least 24 h, while limited tumor penetration by EpCAM antibody was observed after 4 h incubation. As observed from in vivo live animal imaging, EpCAM aptamers displayed a maximum tumor uptake at around 10 min followed by a rapid clearance after 80 min, while the signal of peak uptake and disappearance of antibody appeared at 3 h and 6 h after intravenous injection, respectively. The signal of PEGylated EpCAM aptamers in xenograft tumors was sustained for 26 h, which was 4.3-fold longer than that of the EpCAM antibody. Consistently, there were 1.67-fold and 6.6-fold higher accumulation of PEGylated aptamer in xenograft tumors than that of antibody, at 3 h and 24 h after intravenous administration, respectively. In addition, the aptamer achieved at least a 4-time better tumor penetration in

  2. Mesoporous TiO2-B Microspheres with Superior Rate Performance for Lithium Ion Batteries

    SciTech Connect

    Liu, Hansan; Bi, Zhonghe; Sun, Xiao-Guang; Unocic, Raymond R; Paranthaman, Mariappan Parans; Dai, Sheng; Brown, Gilbert M

    2011-01-01

    Mesoporous TiO2-B microsperes with a favorable material architecture are designed and synthesized for high power lithium ion batteries. This material, combining the advantages of fast lithium transport with a pseudocapacitive mechanism, adequate electrode-electrolyte contact and compact particle packing in electrode layer, shows superior high-rate charge-discharge capability and long-time cyclability for lithium ion batteries.

  3. Covalently coupled hybrid of graphitic carbon nitride with reduced graphene oxide as a superior performance lithium-ion battery anode.

    PubMed

    Fu, Yongsheng; Zhu, Junwu; Hu, Chong; Wu, Xiaodong; Wang, Xin

    2014-11-01

    An in situ chemical synthetic approach has been designed for the fabrication of a covalently coupled hybrid consisting of graphitic carbon nitride (g-C3N4) with reduced graphene oxide (rGO) with differing g-C3N4/rGO ratio. The epoxy groups of graphene oxide (GO) undergo a nucleophilic substitution reaction with dicyandiamide (C2H4N4) to form the C2H4N4-GO composite via a covalent C-N bond, and then both the in situ polymerization of C2H4N4 and the thermal reduction of GO can be achieved at higher temperatures, forming the covalently coupled g-C3N4-rGO. FT-IR, CP-MAS NMR and XPS analyses, clearly revealed a covalent interaction between the g-C3N4 and rGO sheets. The g-C3N4-rGO exhibits an unprecedented high, stable and reversible capacity of 1525 mA h g(-1) at a current density of 100 mA g(-1) after 50 cycles. Even at a large current density of 1000 mA g(-1), a reversible capacity of 943 mA h g(-1) can still be retained. The superior electrochemical performance of g-C3N4-rGO is attributed to the specific characteristics of the unique nanostructure of g-C3N4-rGO and the concerted effects of g-C3N4 and rGO, including covalent interactions between the two moieties, the good conductivity and high special surface area of the nanocomposite, as well as the template effect of the planar amino group of g-C3N4 for the dispersed decoration of Li(+) ions.

  4. Partnering through Training and Practice to Achieve Performance Improvement

    ERIC Educational Resources Information Center

    Lyons, Paul R.

    2010-01-01

    This article presents a partnership effort among managers, trainers, and employees to spring to life performance improvement using the performance templates (P-T) approach. P-T represents a process model as well as a method of training leading to performance improvement. Not only does it add to our repertoire of training and performance management…

  5. Electrochemical design of mesoporous Pt-Ru alloy films with various compositions toward superior electrocatalytic performance.

    PubMed

    Wang, Hongjing; Imura, Masataka; Nemoto, Yoshihiro; Wang, Liang; Jeong, Hu Young; Yokoshima, Tokihiko; Terasaki, Osamu; Yamauchi, Yusuke

    2012-10-01

    Mesoporous Pt-Ru alloy films with various compositions were synthesized by electrochemical plating in an aqueous surfactant solution. After the removal of surfactants, continuous mesoporous Pt-Ru alloy films possessing uniform mesopores with diameter about 7 nm were obtained. The Ru content in the films could be controlled from 0 to 13 at % by changing the precursor compositions. For all the films, the mesostructural periodicities and the mesopore sizes in the films were not changed. Due to the mesoporous structure and the doped Ru content, our mesoporous Pt-Ru films showed superior electrocatalytic activity for methanol oxidation reaction in comparison with the commercially available Pt catalyst.

  6. Student Achievement and Education System Performance in a Developing Country

    ERIC Educational Resources Information Center

    Marshall, Jeffery H.; Chinna, Ung; Hok, Ung Ngo; Tinon, Souer; Veasna, Meung; Nissay, Put

    2012-01-01

    The global spread of national assessment testing activities, and the growing pressure to move beyond basic measures of participation in educational monitoring, means that student achievement measures are likely to become increasingly relevant indicators of systemic progress in the developing world. Using data from the CESSP project in Cambodia,…

  7. Achievement Goals, Motivation, and Performance: A Closer Look.

    ERIC Educational Resources Information Center

    Urdan, Tim; Pajares, Frank; Lapin, Amy Z.

    An achievement goal theory framework was used to examine the relations among goals and a number of other motivational constructs in a sample of middle school students. Participants were 189 eighth graders from a public school in the south. In one session students completed the attitude measures and in another session they completed a mathematics…

  8. Concurrently adjusting interrelated control parameters to achieve optimal engine performance

    SciTech Connect

    Jiang, Li; Lee, Donghoon; Yilmaz, Hakan; Stefanopoulou, Anna

    2015-12-01

    Methods and systems for real-time engine control optimization are provided. A value of an engine performance variable is determined, a value of a first operating condition and a value of a second operating condition of a vehicle engine are detected, and initial values for a first engine control parameter and a second engine control parameter are determined based on the detected first operating condition and the detected second operating condition. The initial values for the first engine control parameter and the second engine control parameter are adjusted based on the determined value of the engine performance variable to cause the engine performance variable to approach a target engine performance variable. In order to cause the engine performance variable to approach the target engine performance variable, adjusting the initial value for the first engine control parameter necessitates a corresponding adjustment of the initial value for the second engine control parameter.

  9. Achieving intelligent performance in autonomous on-road driving

    NASA Astrophysics Data System (ADS)

    Schlenoff, Craig I.; Evans, John M.; Barbera, Anthony J.; Albus, James S.; Messina, Elena R.; Balakirsky, Stephen B.

    2004-12-01

    This paper describes NIST"s efforts in evaluating what it will take to achieve autonomous human-level driving skills in terms of time and funding. NIST has approached this problem from several perspectives: considering the current state-of-the-art in autonomous navigation and extrapolating from there, decomposing the tasks identified by the Department of Transportation for on-road driving and comparing that with accomplishments to date, analyzing computing power requirements by comparison with the human brain, and conducting a Delphi Forecast using the expert researchers in the field of autonomous driving. A detailed description of each of these approaches is provided along with the major finding from each approach and an overall picture of what it will take to achieve human level driving skills in autonomous vehicles.

  10. Orchestrating ACO success: how top performers achieve shared savings.

    PubMed

    Harris, John M; Elizondo, Idette; Brown, Amanda M

    2016-03-01

    Leaders of the top-performing accountable care organizations in the Medicare Shared Savings Program attribute the success of their organizations in large part to seven strategies: Seek action-oriented leadership. Transform primary care physician practices. Keep patients out of the emergency department. Ensure all transitions are smooth. Make effective use of available data. Share information on physician performance. Keep patients engaged.

  11. Effectiveness of a refuge for Lake Trout in Western Lake Superior II: Simulation of future performance

    USGS Publications Warehouse

    Akins, Andrea L; Hansen, Michael J.; Seider, Michael J.

    2015-01-01

    Historically, Lake Superior supported one of the largest and most diverse Lake Trout Salvelinus namaycush fisheries in the Laurentian Great Lakes, but Lake Trout stocks collapsed due to excessive fishery exploitation and predation by Sea Lampreys Petromyzon marinus. Lake Trout stocking, Sea Lamprey control, and fishery regulations, including a refuge encompassing Gull Island Shoal (Apostle Islands region), were used to enable recovery of Lake Trout stocks that used this historically important spawning shoal. Our objective was to determine whether future sustainability of Lake Trout stocks will depend on the presence of the Gull Island Shoal Refuge. We constructed a stochastic age-structured simulation model to assess the effect of maintaining the refuge as a harvest management tool versus removing the refuge. In general, median abundances of age-4, age-4 and older (age-4+), and age-8+ fish collapsed at lower instantaneous fishing mortality rates (F) when the refuge was removed than when the refuge was maintained. With the refuge in place, the F that resulted in collapse depended on the rate of movement into and out of the refuge. Too many fish stayed in the refuge when movement was low (0–2%), and too many fish became vulnerable to fishing when movement was high (≥22%); thus, the refuge was more effective at intermediate rates of movement (10–11%). With the refuge in place, extinction did not occur at any simulated level of F, whereas refuge removal led to extinction at all combinations of commercial F and recreational F. Our results indicate that the Lake Trout population would be sustained by the refuge at all simulated F-values, whereas removal of the refuge would risk population collapse at much lower F (0.700–0.744). Therefore, the Gull Island Shoal Refuge is needed to sustain the Lake Trout population in eastern Wisconsin waters of Lake Superior.

  12. Some methods for achieving more efficient performance of fuel assemblies

    NASA Astrophysics Data System (ADS)

    Boltenko, E. A.

    2014-07-01

    More efficient operation of reactor plant fuel assemblies can be achieved through the use of new technical solutions aimed at obtaining more uniform distribution of coolant over the fuel assembly section, more intense heat removal on convex heat-transfer surfaces, and higher values of departure from nucleate boiling ratio (DNBR). Technical solutions using which it is possible to obtain more intense heat removal on convex heat-transfer surfaces and higher DNBR values in reactor plant fuel assemblies are considered. An alternative heat removal arrangement is described using which it is possible to obtain a significantly higher power density in a reactor plant and essentially lower maximal fuel rod temperature.

  13. Orchestrating ACO success: how top performers achieve shared savings.

    PubMed

    Harris, John M; Elizondo, Idette; Brown, Amanda M

    2016-03-01

    Leaders of the top-performing accountable care organizations in the Medicare Shared Savings Program attribute the success of their organizations in large part to seven strategies: Seek action-oriented leadership. Transform primary care physician practices. Keep patients out of the emergency department. Ensure all transitions are smooth. Make effective use of available data. Share information on physician performance. Keep patients engaged. PMID:27183758

  14. Graphite assisted synthesis of nanoparticles interconnected porous two-dimensional LiMn2O4 nanoplates with superior performance

    NASA Astrophysics Data System (ADS)

    Tan, X. H.; Liu, H. Q.; Jiang, Y.; Liu, G. Y.; Guo, Y. J.; Wang, H. F.; Sun, L. F.; Chu, W. G.

    2016-10-01

    A facile graphite assisted approach is proposed to synthesize high performance LiMn2O4 nanostructures. Graphite plates with different sizes and thicknesses are found to have different influences on the structure, morphology and performance of LiMn2O4. Larger and thicker graphite plates result in 2-D porous LiMn2O4 nanoplates whereas smaller and thinner ones lead to the formation of dispersed nanoparticles. Despite the smaller lattice constant, the shorter Lisbnd O and longer Mnsbnd O bonds, and the lower BET surface area compared to dispersed LiMn2O4 nanoparticles, LiMn2O4 nanoplates formed by primary nanoparticles with similar sizes and morphologies exhibit the superior performance because of the better interparticle electronic conductivity. LiMn2O4 nanoplates show the discharge capacity of 104 mAh g-1 at 50 C and the capacity retention of 70.0% after 1000 cycles for 1 C at RT, better than the corresponding values, 95 mAh g-1 and 64.5% for dispersed LiMn2O4 nanoparticles, respectively. The more superior performance of LiMn2O4 nanoplates compared to dispersed LiMn2O4 nanoparticles is particularly manifested in the case of lower percentage conductive additive, which is very significant for practical application. This simple, cost effective, green and up scalable approach can also be employed to synthesize other 2-D nanostructured materials.

  15. Achieving Transformational Materials Performance in a New Era of Science

    ScienceCinema

    John Sarrao

    2016-07-12

    The inability of current materials to meet performance requirements is a key stumbling block for addressing grand challenges in energy and national security. Fortunately, materials research is on the brink of a new era - a transition from observation and validation of materials properties to prediction and control of materials performance. In this talk, I describe the nature of the current challenge, the prospects for success, and a specific facility concept, MaRIE, that will provide the needed capabilities to meet these challenges, especially for materials in extreme environments. MaRIE, for Matter-Radiation Interactions in Extremes, is Los Alamos' concept to realize this vision of 21st century materials research. This vision will be realized through enhancements to the current LANSCE accelerator, development of a fourth-generation x-ray light source co-located with the proton accelerator, and a comprehensive synthesis and characterization facility focused on controlling complex materials and the defect/structure link to materials performance.

  16. Striving for Excellence Sometimes Hinders High Achievers: Performance-Approach Goals Deplete Arithmetical Performance in Students with High Working Memory Capacity

    PubMed Central

    Crouzevialle, Marie; Smeding, Annique; Butera, Fabrizio

    2015-01-01

    We tested whether the goal to attain normative superiority over other students, referred to as performance-approach goals, is particularly distractive for high-Working Memory Capacity (WMC) students—that is, those who are used to being high achievers. Indeed, WMC is positively related to high-order cognitive performance and academic success, a record of success that confers benefits on high-WMC as compared to low-WMC students. We tested whether such benefits may turn out to be a burden under performance-approach goal pursuit. Indeed, for high achievers, aiming to rise above others may represent an opportunity to reaffirm their positive status—a stake susceptible to trigger disruptive outcome concerns that interfere with task processing. Results revealed that with performance-approach goals—as compared to goals with no emphasis on social comparison—the higher the students’ WMC, the lower their performance at a complex arithmetic task (Experiment 1). Crucially, this pattern appeared to be driven by uncertainty regarding the chances to outclass others (Experiment 2). Moreover, an accessibility measure suggested the mediational role played by status-related concerns in the observed disruption of performance. We discuss why high-stake situations can paradoxically lead high-achievers to sub-optimally perform when high-order cognitive performance is at play. PMID:26407097

  17. Striving for Excellence Sometimes Hinders High Achievers: Performance-Approach Goals Deplete Arithmetical Performance in Students with High Working Memory Capacity.

    PubMed

    Crouzevialle, Marie; Smeding, Annique; Butera, Fabrizio

    2015-01-01

    We tested whether the goal to attain normative superiority over other students, referred to as performance-approach goals, is particularly distractive for high-Working Memory Capacity (WMC) students-that is, those who are used to being high achievers. Indeed, WMC is positively related to high-order cognitive performance and academic success, a record of success that confers benefits on high-WMC as compared to low-WMC students. We tested whether such benefits may turn out to be a burden under performance-approach goal pursuit. Indeed, for high achievers, aiming to rise above others may represent an opportunity to reaffirm their positive status-a stake susceptible to trigger disruptive outcome concerns that interfere with task processing. Results revealed that with performance-approach goals-as compared to goals with no emphasis on social comparison-the higher the students' WMC, the lower their performance at a complex arithmetic task (Experiment 1). Crucially, this pattern appeared to be driven by uncertainty regarding the chances to outclass others (Experiment 2). Moreover, an accessibility measure suggested the mediational role played by status-related concerns in the observed disruption of performance. We discuss why high-stake situations can paradoxically lead high-achievers to sub-optimally perform when high-order cognitive performance is at play. PMID:26407097

  18. Lignocellulose Nanofiber-Reinforced Polystyrene Produced from Composite Microspheres Obtained in Suspension Polymerization Shows Superior Mechanical Performance.

    PubMed

    Ballner, Daniel; Herzele, Sabine; Keckes, Jozef; Edler, Matthias; Griesser, Thomas; Saake, Bodo; Liebner, Falk; Potthast, Antje; Paulik, Christian; Gindl-Altmutter, Wolfgang

    2016-06-01

    A facile approach to obtaining cellulose nanofiber-reinforced polystyrene with greatly improved mechanical performance compared to unreinforced polystyrene is presented. Cellulose nanofibers were obtained by mechanical fibrillation of partially delignified wood (MFLC) and compared to nanofibers obtained from bleached pulp. Residual hemicellulose and lignin imparted amphiphilic surface chemical character to MFLC, which enabled the stabilization of emulsions of styrene in water. Upon suspension polymerization of styrene from the emulsion, polystyrene microspheres coated in MFLC were obtained. When processed into polymer sheets by hot-pressing, improved bending strength and superior impact toughness was observed for the polystyrene-MFLC composite compared to the un-reinforced polystyrene. PMID:27163488

  19. Lignocellulose Nanofiber-Reinforced Polystyrene Produced from Composite Microspheres Obtained in Suspension Polymerization Shows Superior Mechanical Performance.

    PubMed

    Ballner, Daniel; Herzele, Sabine; Keckes, Jozef; Edler, Matthias; Griesser, Thomas; Saake, Bodo; Liebner, Falk; Potthast, Antje; Paulik, Christian; Gindl-Altmutter, Wolfgang

    2016-06-01

    A facile approach to obtaining cellulose nanofiber-reinforced polystyrene with greatly improved mechanical performance compared to unreinforced polystyrene is presented. Cellulose nanofibers were obtained by mechanical fibrillation of partially delignified wood (MFLC) and compared to nanofibers obtained from bleached pulp. Residual hemicellulose and lignin imparted amphiphilic surface chemical character to MFLC, which enabled the stabilization of emulsions of styrene in water. Upon suspension polymerization of styrene from the emulsion, polystyrene microspheres coated in MFLC were obtained. When processed into polymer sheets by hot-pressing, improved bending strength and superior impact toughness was observed for the polystyrene-MFLC composite compared to the un-reinforced polystyrene.

  20. Functional traits contributed to the superior performance of the exotic species Robinia pseudoacacia: a comparison with the native tree Sophora japonica.

    PubMed

    Luo, Yujie; Yuan, Yifu; Wang, Renqing; Liu, Jian; Du, Ning; Guo, Weihua

    2016-03-01

    Functional traits determine the ecological strategies of plants and therefore are widely considered to feature in the success of invasive species. By comparing a widespread exotic invasive species Robinia pseudoacacia L. with a related native one Sophora japonica L., this research aimed to study strategies of R. pseudoacacia for superior performance from the perspective of functional traits. We conducted a greenhouse experiment in which seedlings of R. pseudoacacia and S. japonica were grown separately under a factorial combination of two light regimes and three levels of nitrogen (N) fertilization, including a control and two levels intended to represent ambient and future levels of N deposition in Chinese forests. After 90 days of treatment, performance and functional traits were determined for the two species, the former referred to as the total biomass (TB) that directly affected fitness. Trait plasticity and integration (the pattern and extent of functional covariance among different plant traits) were analyzed and compared. We found that the two species showed significantly different plastic responses to light increase: in the low-light regime, they were similar in performance and functional traits, while in the high-light regime, R. pseudoacacia achieved a significantly higher TB and a suite of divergent but advantageous functional traits versus S. japonica, such as significantly greater photosynthetic capacity and leaf N concentration, and lower carbon-to-N ratio and root-to-shoot ratio, which conferred it the greater performance. Moreover, across the light gradient, R. pseudoacacia showed higher correlations between photosynthetic capacity and other functional traits than S. japonica. In contrast, N deposition showed little impact on our experiment. Our results suggested that across light regimes, three aspects of functional traits contributed to the superior performance of R. pseudoacacia: functional trait divergence, significantly different plasticity of

  1. Functional traits contributed to the superior performance of the exotic species Robinia pseudoacacia: a comparison with the native tree Sophora japonica.

    PubMed

    Luo, Yujie; Yuan, Yifu; Wang, Renqing; Liu, Jian; Du, Ning; Guo, Weihua

    2016-03-01

    Functional traits determine the ecological strategies of plants and therefore are widely considered to feature in the success of invasive species. By comparing a widespread exotic invasive species Robinia pseudoacacia L. with a related native one Sophora japonica L., this research aimed to study strategies of R. pseudoacacia for superior performance from the perspective of functional traits. We conducted a greenhouse experiment in which seedlings of R. pseudoacacia and S. japonica were grown separately under a factorial combination of two light regimes and three levels of nitrogen (N) fertilization, including a control and two levels intended to represent ambient and future levels of N deposition in Chinese forests. After 90 days of treatment, performance and functional traits were determined for the two species, the former referred to as the total biomass (TB) that directly affected fitness. Trait plasticity and integration (the pattern and extent of functional covariance among different plant traits) were analyzed and compared. We found that the two species showed significantly different plastic responses to light increase: in the low-light regime, they were similar in performance and functional traits, while in the high-light regime, R. pseudoacacia achieved a significantly higher TB and a suite of divergent but advantageous functional traits versus S. japonica, such as significantly greater photosynthetic capacity and leaf N concentration, and lower carbon-to-N ratio and root-to-shoot ratio, which conferred it the greater performance. Moreover, across the light gradient, R. pseudoacacia showed higher correlations between photosynthetic capacity and other functional traits than S. japonica. In contrast, N deposition showed little impact on our experiment. Our results suggested that across light regimes, three aspects of functional traits contributed to the superior performance of R. pseudoacacia: functional trait divergence, significantly different plasticity of

  2. The Effects of Parental Involvement on Student Achievement in Three Michigan Performance Contracting Programs.

    ERIC Educational Resources Information Center

    Gillum, Ronald M.; And Others

    Reading achievement of students in second to sixth grade in three school districts participating in a performance-contracting program was tested, using the Stanford Achievement Test and the Metropolitan Achievement Test, at the beginning and the end of the school year. The performance contract for each of the districts included a…

  3. Achieving high sustained performance in an unstructured mesh CFD application

    SciTech Connect

    Keyes, D E; Anderson, W K; Gropp, W D; Kaushik, D K; Smith, B F

    1999-12-10

    This paper highlights a three-year project by an interdisciplinary team on a legacy F77 computational fluid dynamics code, with the aim of demonstrating that implicit unstructured grid simulations can execute at rates not far from those of explicit structured grid codes, provided attention is paid to data motion complexity and the reuse of data positioned at the levels of the memory hierarchy closest to the processor, in addition to traditional operation count complexity. The demonstration code is from NASA and the enabling parallel hardware and (freely available) software toolkit are from DOE, but the resulting methodology should be broadly applicable, and the hardware limitations exposed should allow programmers and vendors of parallel platforms to focus with greater encouragement on sparse codes with indirect addressing. This snapshot of ongoing work shows a performance of 15 microseconds per degree of freedom to steady-state convergence of Euler flow on a mesh with 2.8 million vertices using 3072 dual-processor nodes of ASCI Red, corresponding to a sustained floating-point rate of 0.227 Tflop/s.

  4. Antisaccade performance in schizophrenia: a neural model of decision making in the superior colliculus

    PubMed Central

    Cutsuridis, Vassilis; Kumari, Veena; Ettinger, Ulrich

    2014-01-01

    Antisaccade performance deficits in schizophrenia are generally interpreted as an impaired top–down inhibitory signal failing to suppress the erroneous response. We recorded the antisaccade performance (error rates and latencies) of healthy and schizophrenia subjects performing the mirror antisaccade task. A neural rise-to-threshold model of antisaccade performance was developed to uncover the biophysical mechanisms giving rise to the observed deficits in schizophrenia. Schizophrenia patients displayed greater variability in the antisaccade and corrected antisaccade latency distributions, increased error rates and decreased corrected errors, relative to healthy participants. Our model showed that (1) increased variability is due to a more noisy accumulation of information by schizophrenia patients, but their confidence level required before making a decision is unaffected, and (2) competition between the correct and erroneous decision processes, and not a third top-down inhibitory signal suppressing the erroneous response, accounts for the antisaccade performance of healthy and schizophrenia subjects. Local competition further ensured that a correct antisaccade is never followed by an error prosaccade. PMID:24574953

  5. Ruthenium nanocrystals as cathode catalysts for lithium-oxygen batteries with a superior performance

    PubMed Central

    Sun, Bing; Munroe, Paul; Wang, Guoxiu

    2013-01-01

    The key factor to improve the electrochemical performance of Li-O2 batteries is to find effective cathode catalysts to promote the oxygen reduction and oxygen evolution reactions. Herein, we report the synthesis of an effective cathode catalyst of ruthenium nanocrystals supported on carbon black substrate by a surfactant assisting method. The as-prepared ruthenium nanocrystals exhibited an excellent catalytic activity as cathodes in Li-O2 batteries with a high reversible capacity of about 9,800 mAh g−1, a low charge-discharge over-potential (about 0.37 V), and an outstanding cycle performance up to 150 cycles (with a curtaining capacity of 1,000 mAh g−1). The electrochemical testing shows that ruthenium nanocrystals can significantly reduce the charge potential comparing to carbon black catalysts, which demonstrated that ruthenium based nanomaterials could be effective cathode catalysts for high performance lithium- O2 batteries. PMID:23873349

  6. White Matter Microstructure in Superior Longitudinal Fasciculus Associated with Spatial Working Memory Performance in Children

    ERIC Educational Resources Information Center

    Vestergaard, Martin; Madsen, Kathrine Skak; Baare, William F. C.; Skimminge, Arnold; Ejersbo, Lisser Rye; Ramsoy, Thomas Z.; Gerlach, Christian; Akeson, Per; Paulson, Olaf B.; Jernigan, Terry L.

    2011-01-01

    During childhood and adolescence, ongoing white matter maturation in the fronto-parietal cortices and connecting fiber tracts is measurable with diffusion-weighted imaging. Important questions remain, however, about the links between these changes and developing cognitive functions. Spatial working memory (SWM) performance improves significantly…

  7. Early detection monitoring of aquatic invasive species: Measuring performance success in a Lake Superior pilot network

    EPA Science Inventory

    The Great Lakes Water Quality Agreement, Annex 6 calls for a U.S.-Canada, basin-wide aquatic invasive species early detection network by 2015. The objective of our research is to explore survey design strategies that can improve detection efficiency, and to develop performance me...

  8. Vertically-aligned BCN nanotube arrays with superior performance in electrochemical capacitors.

    PubMed

    Zhou, Junshuang; Li, Na; Gao, Faming; Zhao, Yufeng; Hou, Li; Xu, Ziming

    2014-08-15

    Electrochemical capacitors (EC) have received tremendous interest due to their high potential to satisfy the urgent demand in many advanced applications. The development of new electrode materials is considered to be the most promising approach to enhance the EC performance substantially. Herein, we present a high-capacity capacitor material based on vertically-aligned BC₂N nanotube arrays (VA-BC₂NNTAs) synthesized by low temperature solvothermal route. The obtained VA-BC₂NNTAs display the good aligned nonbuckled tubular structure, which could indeed advantageously enhance capacitor performance. VA-BC₂NNTAs exhibit an extremely high specific capacitance, 547 Fg(-1), which is about 2-6 times larger than that of the presently available carbon-based materials. Meanwhile, VA-BC₂NNTAs maintain an excellent rate capability and high durability. All these characteristics endow VA-BC₂NNTAs an alternative promising candidate for an efficient electrode material for electrochemical capacitors (EC).

  9. High concentration nitrogen doped carbon nanotube anodes with superior Li+ storage performance for lithium rechargeable battery application

    NASA Astrophysics Data System (ADS)

    Li, Xifei; Liu, Jian; Zhang, Yong; Li, Yongliang; Liu, Hao; Meng, Xiangbo; Yang, Jinli; Geng, Dongsheng; Wang, Dongniu; Li, Ruying; Sun, Xueliang

    2012-01-01

    A floating catalyst chemical vapor deposition method has been developed to synthesize carbon nanotubes doped with a high concentration of nitrogen. Their electrochemical performance as anodes for lithium ion batteries (LIBs) in comparison to pristine carbon nanotubes (CNTs) has been investigated. X-ray photoelectron spectroscopy results indicated that the nitrogen content reaches as high as 16.4 at.%. Bamboo-like compartments were fabricated as shown by high resolution transmission electron microscopy. High concentration nitrogen doped carbon nanotubes (HN-CNTs) show approximately double reversible capacity of CNTs: 494 mAh g-1 vs. 260 mAh g-1, and present a much better rate capability than CNTs. The significantly superior electrochemical performance could be related to the high electrical conductivity and the larger number of defect sites in HN-CNTs for anodes of LIBs.

  10. A graphene-based smart catalytic system with superior catalytic performances and temperature responsive catalytic behaviors.

    PubMed

    Qi, Junjie; Lv, Weipeng; Zhang, Guanghui; Li, Yang; Zhang, Guoliang; Zhang, Fengbao; Fan, Xiaobin

    2013-07-21

    We have successfully developed a unique graphene-based smart catalytic system which consists of the graphene supported Au-Pt bimetallic nanocatalyst with a well-defined core-shell structure and a dextran-based temperature-responsive polymer. The unique catalytic system possesses excellent catalytic performances and the catalytic activities could be readily switched on or off at different temperature windows. PMID:23740038

  11. 39 CFR 3055.1 - Annual reporting of service performance achievements.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 39 Postal Service 1 2011-07-01 2011-07-01 false Annual reporting of service performance achievements. 3055.1 Section 3055.1 Postal Service POSTAL REGULATORY COMMISSION PERSONNEL SERVICE PERFORMANCE AND CUSTOMER SATISFACTION REPORTING Annual Reporting of Service Performance Achievements §...

  12. 39 CFR 3055.30 - Periodic reporting of service performance achievements.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 39 Postal Service 1 2011-07-01 2011-07-01 false Periodic reporting of service performance achievements. 3055.30 Section 3055.30 Postal Service POSTAL REGULATORY COMMISSION PERSONNEL SERVICE PERFORMANCE AND CUSTOMER SATISFACTION REPORTING Periodic Reporting of Service Performance Achievements §...

  13. 39 CFR 3055.2 - Contents of the annual report of service performance achievements.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 39 Postal Service 1 2011-07-01 2011-07-01 false Contents of the annual report of service performance achievements. 3055.2 Section 3055.2 Postal Service POSTAL REGULATORY COMMISSION PERSONNEL SERVICE PERFORMANCE AND CUSTOMER SATISFACTION REPORTING Annual Reporting of Service Performance Achievements §...

  14. Cobalt-based metal organic framework with superior lithium anodic performance

    NASA Astrophysics Data System (ADS)

    Hu, Xiaoshi; Hu, Huiping; Li, Chao; Li, Tian; Lou, Xiaobing; Chen, Qun; Hu, Bingwen

    2016-10-01

    The reversible charging of a Co-1,4-benzenedicarboxylate MOF (Co-BDC MOF) prepared via an one-pot solvothermal method was studied for use as the anode in a Li-ion cell. It was found that this MOF anode provides high reversible capacities (1090 and 611 mA h g-1 at current densities of 0.2 and 1 A g-1, respectively), and an impressive rate performance. Such an outstanding Li-ion storage property has not been reported previously for the LIB anodes within the MOFs category. Ex-situ X-ray photoelectron spectroscopy (XPS) and infrared spectroscopy (IR) studies of this material at different state of charge suggest that cobalt stays at Co2+ state during discharge/charge process, so that in this case Li+ may be inserted into the organic moiety without the direct participation of cobalt ions.

  15. Multifunctional graphene sheets embedded in silicone encapsulant for superior performance of light-emitting diodes.

    PubMed

    Lee, Seungae; Hong, Jin-Yong; Jang, Jyongsik

    2013-07-23

    Graphene nanosheets with uniform shape are successfully incorporated into a silicone encapsulant of a light-emitting diode (LED) using a solvent-exchange approach which is a facile and straightforward method. The graphene nanosheets embedded in the silicone encapsulant have a multifunctional role which improves the performance of light-emitting diodes. The presence of graphene gives rise to effective heat dissipation, improvement of protection ability from external stimuli, such as moisture and hazardous gas, and enhancement of mechanical properties such as elastic modulus and fracture toughness. Consequently, the LEDs composed of a graphene-embedded silicone encapsulant exhibit long-term stability without loss of luminous efficiency by addition of relatively small amounts of graphene. This novel strategy offers a feasible candidate for their practical or industrial applications. PMID:23758228

  16. Sub-10 nm Ta Channel Responsible for Superior Performance of a HfO2 Memristor

    NASA Astrophysics Data System (ADS)

    Jiang, Hao; Han, Lili; Lin, Peng; Wang, Zhongrui; Jang, Moon Hyung; Wu, Qing; Barnell, Mark; Yang, J. Joshua; Xin, Huolin L.; Xia, Qiangfei

    2016-06-01

    Memristive devices are promising candidates for the next generation non-volatile memory and neuromorphic computing. It has been widely accepted that the motion of oxygen anions leads to the resistance changes for valence-change-memory (VCM) type of materials. Only very recently it was speculated that metal cations could also play an important role, but no direct physical characterizations have been reported yet. Here we report a Ta/HfO2/Pt memristor with fast switching speed, record high endurance (120 billion cycles) and reliable retention. We programmed the device to 24 discrete resistance levels, and also demonstrated over a million (220) epochs of potentiation and depression, suggesting that our devices can be used for both multi-level non-volatile memory and neuromorphic computing applications. More importantly, we directly observed a sub-10 nm Ta-rich and O-deficient conduction channel within the HfO2 layer that is responsible for the switching. This work deepens our understanding of the resistance switching mechanism behind oxide-based memristive devices and paves the way for further device performance optimization for a broad spectrum of applications.

  17. Vertical jumping performance of bonobo (Pan paniscus) suggests superior muscle properties.

    PubMed

    Scholz, Melanie N; D'Août, Kristiaan; Bobbert, Maarten F; Aerts, Peter

    2006-09-01

    Vertical jumping was used to assess muscle mechanical output in bonobos and comparisons were drawn to human jumping. Jump height, defined as the vertical displacement of the body centre of mass during the airborne phase, was determined for three bonobos of varying age and sex. All bonobos reached jump heights above 0.7 m, which greatly exceeds typical human maximal performance (0.3-0.4m). Jumps by one male bonobo (34 kg) and one human male (61.5 kg) were analysed using an inverse dynamics approach. Despite the difference in size, the mechanical output delivered by the bonobo and the human jumper during the push-off was similar: about 450 J, with a peak power output close to 3000 W. In the bonobo, most of the mechanical output was generated at the hips. To account for the mechanical output, the muscles actuating the bonobo's hips (directly and indirectly) must deliver muscle-mass-specific power and work output of 615 Wkg-1 and 92 Jkg-1, respectively. This was twice the output expected on the basis of muscle mass specific work and power in other jumping animals but seems physiologically possible. We suggest that the difference is due to a higher specific force (force per unit of cross-sectional area) in the bonobo.

  18. Vertical jumping performance of bonobo (Pan paniscus) suggests superior muscle properties

    PubMed Central

    Scholz, Melanie N; D'Août, Kristiaan; Bobbert, Maarten F; Aerts, Peter

    2006-01-01

    Vertical jumping was used to assess muscle mechanical output in bonobos and comparisons were drawn to human jumping. Jump height, defined as the vertical displacement of the body centre of mass during the airborne phase, was determined for three bonobos of varying age and sex. All bonobos reached jump heights above 0.7 m, which greatly exceeds typical human maximal performance (0.3–0.4 m). Jumps by one male bonobo (34 kg) and one human male (61.5 kg) were analysed using an inverse dynamics approach. Despite the difference in size, the mechanical output delivered by the bonobo and the human jumper during the push-off was similar: about 450 J, with a peak power output close to 3000 W. In the bonobo, most of the mechanical output was generated at the hips. To account for the mechanical output, the muscles actuating the bonobo's hips (directly and indirectly) must deliver muscle-mass-specific power and work output of 615 W kg−1 and 92 J kg−1, respectively. This was twice the output expected on the basis of muscle mass specific work and power in other jumping animals but seems physiologically possible. We suggest that the difference is due to a higher specific force (force per unit of cross-sectional area) in the bonobo. PMID:16901837

  19. Sub-10 nm Ta Channel Responsible for Superior Performance of a HfO2 Memristor

    PubMed Central

    Jiang, Hao; Han, Lili; Lin, Peng; Wang, Zhongrui; Jang, Moon Hyung; Wu, Qing; Barnell, Mark; Yang, J. Joshua; Xin, Huolin L.; Xia, Qiangfei

    2016-01-01

    Memristive devices are promising candidates for the next generation non-volatile memory and neuromorphic computing. It has been widely accepted that the motion of oxygen anions leads to the resistance changes for valence-change-memory (VCM) type of materials. Only very recently it was speculated that metal cations could also play an important role, but no direct physical characterizations have been reported yet. Here we report a Ta/HfO2/Pt memristor with fast switching speed, record high endurance (120 billion cycles) and reliable retention. We programmed the device to 24 discrete resistance levels, and also demonstrated over a million (220) epochs of potentiation and depression, suggesting that our devices can be used for both multi-level non-volatile memory and neuromorphic computing applications. More importantly, we directly observed a sub-10 nm Ta-rich and O-deficient conduction channel within the HfO2 layer that is responsible for the switching. This work deepens our understanding of the resistance switching mechanism behind oxide-based memristive devices and paves the way for further device performance optimization for a broad spectrum of applications. PMID:27334443

  20. Designed Synthesis of Transition Metal/Oxide Hierarchical Peapods Array with the Superior Lithium Storage Performance

    PubMed Central

    Zhang, Huijuan; Bai, Yuanjuan; Zhang, Yan; Li, Xiao; Feng, Yangyang; Liu, Qing; Wu, Kai; Wang, Yu

    2013-01-01

    In this report, a novel hierarchical peapoded array with Co3O4 nanoparticles encapsulated in graphitized carbon fiber is introduced for the first time. The unique peapoded structure is suitable for the excellent anode in LIBs and demonstrates enhanced rate capability, cyclability and prolonged lifespan, e.g. the specific capacity can reach up to 1150 mAh/g. All the enhanced electrochemical performance is reasonably derived from the peapod-like and aligned conformation. Furthermore, due to the specialty of the structure and the versatility of Co3O4, the composite will find more applications in specific catalysis, biomedicine, electronics, optoelectronic engineering and gas sensing. The fabrication strategy developed here is also a rational and universal approach towards peapod-like architecture and has significantly widened the specific functional material domain we created before. In our design, more peapod-like aligned samples with various nanoparticles, e.g. oxides, phosphides, even nitrides, encapsulated in graphitized carbon fibers, have been lifted on the research agenda and the results will be presented soon. PMID:24056414

  1. Superior Antifouling Performance of a Zwitterionic Peptide Compared to an Amphiphilic, Non-Ionic Peptide.

    PubMed

    Ye, Huijun; Wang, Libing; Huang, Renliang; Su, Rongxin; Liu, Boshi; Qi, Wei; He, Zhimin

    2015-10-14

    The aim of this study was to explore the influence of amphiphilic and zwitterionic structures on the resistance of protein adsorption to peptide self-assembled monolayers (SAMs) and gain insight into the associated antifouling mechanism. Two kinds of cysteine-terminated heptapeptides were studied. One peptide had alternating hydrophobic and hydrophilic residues with an amphiphilic sequence of CYSYSYS. The other peptide (CRERERE) was zwitterionic. Both peptides were covalently attached onto gold substrates via gold-thiol bond formation. Surface plasmon resonance analysis results showed that both peptide SAMs had ultralow or low protein adsorption amounts of 1.97-11.78 ng/cm2 in the presence of single proteins. The zwitterionic peptide showed relatively higher antifouling ability with single proteins and natural complex protein media. We performed molecular dynamics simulations to understand their respective antifouling behaviors. The results indicated that strong surface hydration of peptide SAMs contributes to fouling resistance by impeding interactions with proteins. Compared to the CYSYSYS peptide, more water molecules were predicted to form hydrogen-bonding interactions with the zwitterionic CRERERE peptide, which is in agreement with the antifouling test results. These findings reveal a clear relation between peptide structures and resistance to protein adsorption, facilitating the development of novel peptide-containing antifouling materials.

  2. Sub-10 nm Ta Channel Responsible for Superior Performance of a HfO2 Memristor.

    PubMed

    Jiang, Hao; Han, Lili; Lin, Peng; Wang, Zhongrui; Jang, Moon Hyung; Wu, Qing; Barnell, Mark; Yang, J Joshua; Xin, Huolin L; Xia, Qiangfei

    2016-06-23

    Memristive devices are promising candidates for the next generation non-volatile memory and neuromorphic computing. It has been widely accepted that the motion of oxygen anions leads to the resistance changes for valence-change-memory (VCM) type of materials. Only very recently it was speculated that metal cations could also play an important role, but no direct physical characterizations have been reported yet. Here we report a Ta/HfO2/Pt memristor with fast switching speed, record high endurance (120 billion cycles) and reliable retention. We programmed the device to 24 discrete resistance levels, and also demonstrated over a million (2(20)) epochs of potentiation and depression, suggesting that our devices can be used for both multi-level non-volatile memory and neuromorphic computing applications. More importantly, we directly observed a sub-10 nm Ta-rich and O-deficient conduction channel within the HfO2 layer that is responsible for the switching. This work deepens our understanding of the resistance switching mechanism behind oxide-based memristive devices and paves the way for further device performance optimization for a broad spectrum of applications.

  3. Boredom in Achievement Settings: Exploring Control-Value Antecedents and Performance Outcomes of a Neglected Emotion

    ERIC Educational Resources Information Center

    Pekrun, Reinhard; Goetz, Thomas; Daniels, Lia M.; Stupnisky, Robert H.; Perry, Raymond P.

    2010-01-01

    The linkages of achievement-related boredom with students' appraisals and performance outcomes were examined in a series of 5 exploratory, cross-sectional, and predictive investigations. Studies 1 and 2 assessed students' boredom in a single achievement episode (i.e., state achievement boredom); Studies 3, 4, and 5 focused on their habitual…

  4. Ultra-small Fe3O4 nanoparticle decorated graphene nanosheets with superior cyclic performance and rate capability

    NASA Astrophysics Data System (ADS)

    Chen, Yu; Song, Bohang; Lu, Li; Xue, Junmin

    2013-07-01

    Advanced anode materials for next generation lithium ion batteries have attracted great interest due to the ever increasing demand for powerful, light-weight, and compact electrical devices. In this work, graphene nanosheets decorated with ultra-small Fe3O4 nanoparticles (USIO/G) were synthesized via a facile hydrothermal method. Compared with other reported Fe3O4-based anode composites, USIO/G demonstrated superior cyclic ability and excellent rate capability owing to its ultra-small size of active lithium storage sites, Fe3O4, with an average diameter less than 5 nm. Furthermore, graphene nanosheets played an important role in the overall electrochemical performance of the composite by enhancing the electrical conductivity, forming a flexible network, and providing extra lithium storage sites. The obtained composites were tested for electrochemical performance for a total number of 2120 cycles: a rate capability test with current densities ranged from 90 to 7200 mA g-1 for 920 cycles, followed by a cycling test at 1800 mA g-1 for 1200 cycles. For the rate capability test, steady reversible capacities were delivered under each current density with final reversible capacities of 1177, 1096, 833, 488, 242, and 146 mA h g-1 at 90, 180, 900, 1800, 3600, and 7200 mA g-1, respectively. The subsequent cyclic test demonstrated the superior cyclic stability of USIO/G and a reversible capacity of 437 mA h g-1 at the 2120th cycle was delivered.Advanced anode materials for next generation lithium ion batteries have attracted great interest due to the ever increasing demand for powerful, light-weight, and compact electrical devices. In this work, graphene nanosheets decorated with ultra-small Fe3O4 nanoparticles (USIO/G) were synthesized via a facile hydrothermal method. Compared with other reported Fe3O4-based anode composites, USIO/G demonstrated superior cyclic ability and excellent rate capability owing to its ultra-small size of active lithium storage sites, Fe3O4, with

  5. Sacrificial template-directed synthesis of mesoporous magnesium oxide architectures with superior performance for organic dye adsorption [corrected].

    PubMed

    Ai, Lunhong; Yue, Haitao; Jiang, Jing

    2012-09-01

    Mesoporous MgO architectures were successfully synthesized by the direct thermal transformation of the sacrificial oxalate template. The as-prepared mesoporous architectures were characterized by X-ray diffraction (XRD), scanning electronic microscopy (SEM), transmission electron microscopy (TEM), X-ray energy dispersive spectroscopy (EDS), Fourier transform infrared spectroscopy (FTIR), and nitrogen adsorption-desorption techniques. The MgO architectures showed extraordinary adsorption capacity and rapid adsorption rate for removal of Congo red (CR) from water. The maximum adsorption capacity of the MgO architectures toward CR reached 689.7 mg g⁻¹, much higher than most of the previously reported hierarchical adsorbents. The CR removal process was found to obey the Langmuir adsorption model and its kinetics followed pseudo-second-order rate equation. The superior adsorption performance of the mesoporous MgO architectures could be attributed to the unique mesoporous structure, high specific surface area as well as strong electrostatic interaction.

  6. Performance Trajectories and Performance Gaps as Achievement Effect-Size Benchmarks for Educational Interventions

    ERIC Educational Resources Information Center

    Bloom, Howard S.; Hill, Carolyn J.; Black, Alison Rebeck; Lipsey, Mark W.

    2008-01-01

    Two complementary approaches to developing empirical benchmarks for achievement effect sizes in educational interventions are explored. The first approach characterizes the natural developmental progress in achievement made by students from one year to the next as effect sizes. Data for seven nationally standardized achievement tests show large…

  7. Students' Achievement Goals, Emotion Perception Ability and Affect and Performance in the Classroom: A Multilevel Examination

    ERIC Educational Resources Information Center

    Vassiou, Aikaterini; Mouratidis, Athanasios; Andreou, Eleni; Kafetsios, Konstantinos

    2016-01-01

    Performance at school is affected not only by students' achievement goals but also by emotional exchanges among classmates and their teacher. In this study, we investigated relationships between students' achievement goals and emotion perception ability and class affect and performance. Participants were 949 Greek adolescent students in 49 classes…

  8. A Comparison of Low Performing Students' Achievements in Factoring Cubic Polynomials Using Three Different Strategies

    ERIC Educational Resources Information Center

    Ogbonnaya, Ugorji I.; Mogari, David L.; Machisi, Eric

    2013-01-01

    In this study, repeated measures design was employed to compare low performing students' achievements in factoring cubic polynomials using three strategies. Twenty-five low-performing Grade 12 students from a secondary school in Limpopo province took part in the study. Data was collected using achievement test and was analysed using repeated…

  9. Predicting Examination Performance Using an Expanded Integrated Hierarchical Model of Test Emotions and Achievement Goals

    ERIC Educational Resources Information Center

    Putwain, Dave; Deveney, Carolyn

    2009-01-01

    The aim of this study was to examine an expanded integrative hierarchical model of test emotions and achievement goal orientations in predicting the examination performance of undergraduate students. Achievement goals were theorised as mediating the relationship between test emotions and performance. 120 undergraduate students completed…

  10. Facile synthesis of core-shell structured PANI-Co3O4 nanocomposites with superior electrochemical performance in supercapacitors

    NASA Astrophysics Data System (ADS)

    Hai, Zhenyin; Gao, Libo; Zhang, Qiang; Xu, Hongyan; Cui, Danfeng; Zhang, Zengxing; Tsoukalas, Dimitris; Tang, Jun; Yan, Shubin; Xue, Chenyang

    2016-01-01

    Core-shell structured PANI-Co3O4 nanocomposites for supercapacitor applications were synthesized by combination of carbon-assisted method and in situ polymerization method. The crystalline structure, optical band gap, morphology, and hydrophilic property, as the major factors affecting the performances of supercapacitors, were investigated by X-ray diffraction (XRD), UV-vis spectrophotometry (UV-vis), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and water contact angle (WCA). The core-shell structured PANI-Co3O4 nanocomposites are characterized by amorphous PANI, small bandgaps, large surface area and favorable hydrophilicity, which indicates the superior electrochemical performances of the nanocomposites as electrode material for supercapacitors. Cyclic voltammetry (CV), galvanostatic charge/discharge and electrochemical impedance spectroscopy (EIS) measurements were conducted in 6 M KOH aqueous solution to evaluate the electrochemical performances. The results shows that core-shell structured PANI-Co3O4 nanocomposites exhibit a high specific capacitance of 1184 F g-1 at 1.25 A g-1, excellent cycling stability of a capacitance retention of 84.9% after 1000 galvanostatic charge/discharge cycles, good electrical conductivity and ion diffusion behavior.

  11. Performance evaluation of iterative reconstruction algorithms for achieving CT radiation dose reduction - a phantom study.

    PubMed

    Dodge, Cristina T; Tamm, Eric P; Cody, Dianna D; Liu, Xinming; Jensen, Corey T; Wei, Wei; Kundra, Vikas; Rong, X John

    2016-01-01

    The purpose of this study was to characterize image quality and dose performance with GE CT iterative reconstruction techniques, adaptive statistical iterative recontruction (ASiR), and model-based iterative reconstruction (MBIR), over a range of typical to low-dose intervals using the Catphan 600 and the anthropomorphic Kyoto Kagaku abdomen phantoms. The scope of the project was to quantitatively describe the advantages and limitations of these approaches. The Catphan 600 phantom, supplemented with a fat-equivalent oval ring, was scanned using a GE Discovery HD750 scanner at 120 kVp, 0.8 s rotation time, and pitch factors of 0.516, 0.984, and 1.375. The mA was selected for each pitch factor to achieve CTDIvol values of 24, 18, 12, 6, 3, 2, and 1 mGy. Images were reconstructed at 2.5 mm thickness with filtered back-projection (FBP); 20%, 40%, and 70% ASiR; and MBIR. The potential for dose reduction and low-contrast detectability were evaluated from noise and contrast-to-noise ratio (CNR) measurements in the CTP 404 module of the Catphan. Hounsfield units (HUs) of several materials were evaluated from the cylinder inserts in the CTP 404 module, and the modulation transfer function (MTF) was calculated from the air insert. The results were con-firmed in the anthropomorphic Kyoto Kagaku abdomen phantom at 6, 3, 2, and 1mGy. MBIR reduced noise levels five-fold and increased CNR by a factor of five compared to FBP below 6mGy CTDIvol, resulting in a substantial improvement in image quality. Compared to ASiR and FBP, HU in images reconstructed with MBIR were consistently lower, and this discrepancy was reversed by higher pitch factors in some materials. MBIR improved the conspicuity of the high-contrast spatial resolution bar pattern, and MTF quantification confirmed the superior spatial resolution performance of MBIR versus FBP and ASiR at higher dose levels. While ASiR and FBP were relatively insensitive to changes in dose and pitch, the spatial resolution for MBIR

  12. Unlocking the Origin of Superior Performance of a Si-Ge Core-Shell Nanowire Quantum Dot Field Effect Transistor.

    PubMed

    Dhungana, Kamal B; Jaishi, Meghnath; Pati, Ranjit

    2016-07-13

    The sustained advancement in semiconducting core-shell nanowire technology has unlocked a tantalizing route for making next generation field effect transistor (FET). Understanding how to control carrier mobility of these nanowire channels by applying a gate field is the key to developing a high performance FET. Herein, we have identified the switching mechanism responsible for the superior performance of a Si-Ge core-shell nanowire quantum dot FET over its homogeneous Si counterpart. A quantum transport approach is used to investigate the gate-field modulated switching behavior in electronic current for ultranarrow Si and Si-Ge core-shell nanowire quantum dot FETs. Our calculations reveal that for the ON state, the gate-field induced transverse localization of the wave function restricts the carrier transport to the outer (shell) layer with the pz orbitals providing the pathway for tunneling of electrons in the channels. The higher ON state current in the Si-Ge core-shell nanowire FET is attributed to the pz orbitals that are distributed over the entire channel; in the case of Si nanowire, the participating pz orbital is restricted to a few Si atoms in the channel resulting in a smaller tunneling current. Within the gate bias range considered here, the transconductance is found to be substantially higher in the case of a Si-Ge core-shell nanowire FET than in a Si nanowire FET, which suggests a much higher mobility in the Si-Ge nanowire device.

  13. Superior thermoelectric performance in PbTe-PbS pseudo-binary. Extremely low thermal conductivity and modulated carrier concentration

    DOE PAGES

    Wu, D.; Zhao, L. -D.; Tong, X.; Li, W.; Wu, L.; Tan, Q.; Pei, Y.; Huang, L.; Li, J. -F.; Zhu, Y.; et al

    2015-05-19

    Lead chalcogenides have exhibited their irreplaceable role as thermoelectric materials at the medium temperature range, owing to highly degenerate electronic bands and intrinsically low thermal conductivities. PbTe-PbS pseudo-binary has been paid extensive attentions due to the even lower thermal conductivity which originates largely from the coexistence of both alloying and phase-separated precipitations. To investigate the competition between alloying and phase separation and its pronounced effect on the thermoelectric performance in PbTe-PbS, we systematically studied Spark Plasma Sintered (SPSed), 3 at% Na- doped (PbTe)1-x(PbS)x samples with x=10%, 15%, 20%, 25%, 30% and 35% by means of transmission electron microscopy (TEM) observationsmore » and theoretical calculations. Corresponding to the lowest lattice thermal conductivity as a result of the balance between point defect- and precipitates- scattering, the highest figure of merit ZT~2.3 was obtained at 923 K when PbS phase fraction x is at 20%. The consistently lower lattice thermal conductivities in SPSed samples compared with corresponding ingots, resulting from the powdering and follow-up consolidation processes, also contribute to the observed superior ZT. Notably, the onset of carrier concentration modulation ~600 K due to excessive Na’s diffusion and re-dissolution leads to the observed saturations of electrical transport properties, which is believed equally crucial to the outstanding thermoelectric performance of SPSed PbTe-PbS samples.« less

  14. Unlocking the Origin of Superior Performance of a Si-Ge Core-Shell Nanowire Quantum Dot Field Effect Transistor.

    PubMed

    Dhungana, Kamal B; Jaishi, Meghnath; Pati, Ranjit

    2016-07-13

    The sustained advancement in semiconducting core-shell nanowire technology has unlocked a tantalizing route for making next generation field effect transistor (FET). Understanding how to control carrier mobility of these nanowire channels by applying a gate field is the key to developing a high performance FET. Herein, we have identified the switching mechanism responsible for the superior performance of a Si-Ge core-shell nanowire quantum dot FET over its homogeneous Si counterpart. A quantum transport approach is used to investigate the gate-field modulated switching behavior in electronic current for ultranarrow Si and Si-Ge core-shell nanowire quantum dot FETs. Our calculations reveal that for the ON state, the gate-field induced transverse localization of the wave function restricts the carrier transport to the outer (shell) layer with the pz orbitals providing the pathway for tunneling of electrons in the channels. The higher ON state current in the Si-Ge core-shell nanowire FET is attributed to the pz orbitals that are distributed over the entire channel; in the case of Si nanowire, the participating pz orbital is restricted to a few Si atoms in the channel resulting in a smaller tunneling current. Within the gate bias range considered here, the transconductance is found to be substantially higher in the case of a Si-Ge core-shell nanowire FET than in a Si nanowire FET, which suggests a much higher mobility in the Si-Ge nanowire device. PMID:27280769

  15. Superior thermoelectric performance in PbTe-PbS pseudo-binary. Extremely low thermal conductivity and modulated carrier concentration

    SciTech Connect

    Wu, D.; Zhao, L. -D.; Tong, X.; Li, W.; Wu, L.; Tan, Q.; Pei, Y.; Huang, L.; Li, J. -F.; Zhu, Y.; Kanatzidis, M. G.; He, J.

    2015-05-19

    Lead chalcogenides have exhibited their irreplaceable role as thermoelectric materials at the medium temperature range, owing to highly degenerate electronic bands and intrinsically low thermal conductivities. PbTe-PbS pseudo-binary has been paid extensive attentions due to the even lower thermal conductivity which originates largely from the coexistence of both alloying and phase-separated precipitations. To investigate the competition between alloying and phase separation and its pronounced effect on the thermoelectric performance in PbTe-PbS, we systematically studied Spark Plasma Sintered (SPSed), 3 at% Na- doped (PbTe)1-x(PbS)x samples with x=10%, 15%, 20%, 25%, 30% and 35% by means of transmission electron microscopy (TEM) observations and theoretical calculations. Corresponding to the lowest lattice thermal conductivity as a result of the balance between point defect- and precipitates- scattering, the highest figure of merit ZT~2.3 was obtained at 923 K when PbS phase fraction x is at 20%. The consistently lower lattice thermal conductivities in SPSed samples compared with corresponding ingots, resulting from the powdering and follow-up consolidation processes, also contribute to the observed superior ZT. Notably, the onset of carrier concentration modulation ~600 K due to excessive Na’s diffusion and re-dissolution leads to the observed saturations of electrical transport properties, which is believed equally crucial to the outstanding thermoelectric performance of SPSed PbTe-PbS samples.

  16. Superior Light-Harvesting Heteroleptic Ruthenium(II) Complexes with Electron-Donating Antennas for High Performance Dye-Sensitized Solar Cells.

    PubMed

    Chen, Wang-Chao; Kong, Fan-Tai; Li, Zhao-Qian; Pan, Jia-Hong; Liu, Xue-Peng; Guo, Fu-Ling; Zhou, Li; Huang, Yang; Yu, Ting; Dai, Song-Yuan

    2016-08-01

    Three heteroleptic polypyridyl ruthenium complexes, RC-41, RC-42, and RC-43, with efficient electron-donating antennas in the ancillary ligands were designed, synthesized, and characterized as sensitizers for dye-sensitized solar cell. All the RC dye sensitizers showed remarkable light-harvesting capacity and broadened absorption range. Significantly, RC-43 obtained the lower energy metal-ligand charge transfer (MLCT) band peaked at 557 nm with a high molar extinction coefficient of 27 400 M(-1) cm(-1). In conjunction with TiO2 photoanode of submicrospheres and iodide-based electrolytes, the DSSCs sensitizing with the RC sensitizers, achieved impressively high short-circuit current density (19.04 mA cm(-2) for RC-41, 19.83 mA cm(-2) for RC-42, and 20.21 mA cm(-2) for RC-43) and power conversion efficiency (10.07% for RC-41, 10.52% for RC-42, and 10.78% for RC-43). The superior performances of RC dye sensitizers were attributed to the enhanced light-harvesting capacity and incident-photon-to-current efficiency (IPCE) caused by the introduction of electron-donating antennas in the ancillary ligands. The interfacial charge recombination/regeneration kinetics and electron lifetime were further evaluated by the electrochemical impedance spectroscopy (EIS) and transient absorption spectroscopy (TAS). These data decisively revealed the dependences on the photovoltaic performance of ruthenium sensitizers incorporating electron-donating antennas. PMID:27409513

  17. Superior Light-Harvesting Heteroleptic Ruthenium(II) Complexes with Electron-Donating Antennas for High Performance Dye-Sensitized Solar Cells.

    PubMed

    Chen, Wang-Chao; Kong, Fan-Tai; Li, Zhao-Qian; Pan, Jia-Hong; Liu, Xue-Peng; Guo, Fu-Ling; Zhou, Li; Huang, Yang; Yu, Ting; Dai, Song-Yuan

    2016-08-01

    Three heteroleptic polypyridyl ruthenium complexes, RC-41, RC-42, and RC-43, with efficient electron-donating antennas in the ancillary ligands were designed, synthesized, and characterized as sensitizers for dye-sensitized solar cell. All the RC dye sensitizers showed remarkable light-harvesting capacity and broadened absorption range. Significantly, RC-43 obtained the lower energy metal-ligand charge transfer (MLCT) band peaked at 557 nm with a high molar extinction coefficient of 27 400 M(-1) cm(-1). In conjunction with TiO2 photoanode of submicrospheres and iodide-based electrolytes, the DSSCs sensitizing with the RC sensitizers, achieved impressively high short-circuit current density (19.04 mA cm(-2) for RC-41, 19.83 mA cm(-2) for RC-42, and 20.21 mA cm(-2) for RC-43) and power conversion efficiency (10.07% for RC-41, 10.52% for RC-42, and 10.78% for RC-43). The superior performances of RC dye sensitizers were attributed to the enhanced light-harvesting capacity and incident-photon-to-current efficiency (IPCE) caused by the introduction of electron-donating antennas in the ancillary ligands. The interfacial charge recombination/regeneration kinetics and electron lifetime were further evaluated by the electrochemical impedance spectroscopy (EIS) and transient absorption spectroscopy (TAS). These data decisively revealed the dependences on the photovoltaic performance of ruthenium sensitizers incorporating electron-donating antennas.

  18. Construct Validity of the Computerized Continuous Performance Test with Measures of Intelligence, Achievement, and Behavior.

    ERIC Educational Resources Information Center

    Campbell, Janice Whitten; And Others

    1991-01-01

    Administered Continuous Performance Test (CPT), Wechsler Intelligence Scale for Children-Revised, Wide Range Achievement Test-Revised, Bender Visual-Motor Gestalt Test, and reading comprehension subtest of Peabody Individual Achievement Test to 54 school-aged children and adolescents referred for evaluation of learning disabilities. Parents…

  19. Cognitive Performance, School Behavior, and Achievement of Children from One-Parent Households.

    ERIC Educational Resources Information Center

    Hetherington, E. Mavis; And Others

    This report reviews the research literature on the effects of divorce and one-parent childrearing on academic achievement and intellectual functioning in children. Life changes following the decision to separate are described along with scholastic achievement measured by IQ and aptitude tests and patterns of cognitive performance. Factors…

  20. Do Performance Goals Promote Learning? A Pattern Analysis of Singapore Students' Achievement Goals

    ERIC Educational Resources Information Center

    Luo, Wenshu; Paris, Scott G.; Hogan, David; Luo, Zhiqiang

    2011-01-01

    This study investigated how achievement goals are combined to affect students' learning. We used a multiple goals perspective, based on mastery (i.e., mastery approach) and performance (including both approach and avoidance components) goals, to examine the achievement goal patterns of 1697 Singapore Secondary 3 students in their math study. Four…

  1. College Performance of New Maryland High School Graduates. Student Outcome and Achievement Report (SOAR)

    ERIC Educational Resources Information Center

    Maryland Higher Education Commission, 2009

    2009-01-01

    The 2009 SOAR (Student Outcome and Achievement Report) relies upon two sets of data, the academic performance data (which are collected directly from the colleges and universities) and the SAT (Scholastic Assessment Test)/ACT (American College Testing Program) data, to examine the relationship between students' academic achievements and…

  2. The Effects of Gender and Attributions on Achievement Motivation and Subsequent Performance.

    ERIC Educational Resources Information Center

    Carlson, Sibylle J.; Latta, R. Michael

    One attributional model of achievement proposes that individuals attribute their own and others' performance outcomes to one or more of four causes, i.e., ability, effort, task difficulty, and luck, and that such attributions have motivational significance for subsequent achievement-related behavior. The effects of gender, level of resultant…

  3. Superior electrochemical performance of Li3VO4/NiO/Ni electrode via a coordinated electrochemical reconstruction

    NASA Astrophysics Data System (ADS)

    Ni, Shibing; Zhang, Jicheng; Lv, Xiaohu; Yang, Xuelin; Zhang, Lulu

    2015-09-01

    Coordinated electrochemical effect between Li3VO4 and NiO occurs in Li3VO4/NiO/Ni electrodes owing to the close potential regions of lithiation and delithiation for Li3VO4 and NiO. Remarkably, Li3VO4/NiO/Ni with bottom nanowalls and upper micro-flowers architecture undergoes a novel coordinated electrochemical reconstruction owing to well coordinated morphology variation of Li3VO4 and NiO in lithiation and delithiation process, which leads to the formation of a new symmetrical porous architecture in cycling, resulting in superior electrochemical performance. At a specific current of 70 mA g-1, it exhibits discharge and charge capacity of 860 and 631 mAh g-1 in the initial cycle, maintaining of 612 and 604 mAh g-1 after 100 cycles. After 60 cycles at various specific currents from 54 to 2700 mA g-1, the discharge and charge capacity can restore to 612 mAh g-1 when reverting the specific current to 54 mA g-1.

  4. A methodology to assess performance of human-robotic systems in achievement of collective tasks

    NASA Technical Reports Server (NTRS)

    Howard, Ayanna M.

    2005-01-01

    In this paper, we present a methodology to assess system performance of human-robotic systems in achievement of collective tasks such as habitat construction, geological sampling, and space exploration.

  5. Performance-Based Assessment, Science Festival Exhibit Presentations, and Elementary Science Achievement.

    ERIC Educational Resources Information Center

    Parker, Verilette A.; Gerber, Brian L.

    2002-01-01

    Describes the effective use of performance-based assessment for evaluating fifth- and sixth-grade student achievement as demonstrated by student exhibit presentations at a science festival. Individual evaluation scores and group negotiated evaluations were consistent. (Author/MM)

  6. Performance-Approach and Performance-Avoidance Classroom Goals and the Adoption of Personal Achievement Goals

    ERIC Educational Resources Information Center

    Schwinger, Malte; Stiensmeier-Pelster, Joachim

    2011-01-01

    Background: Students' perceptions of classroom goals influence their adoption of personal goals. To assess different forms of classroom goals, recent studies have favoured an overall measure of performance classroom goals, compared to a two-dimensional assessment of performance-approach and performance-avoidance classroom goals (PAVCG). Aims: This…

  7. Can achievement emotions be used to better understand motivation, learning, and performance in medical education?

    PubMed

    Artino, Anthony R; Holmboe, Eric S; Durning, Steven J

    2012-01-01

    In this article, we consider an emergent theory of human emotion. The overarching purpose of the article is to introduce medical education researchers to the notion of achievement emotions and provide a brief overview of how this work can inform the theory, research, and practice of medical education. First, we define achievement emotions and describe one of the leading contemporary theories of achievement emotions, control-value theory (Pekrun R. 2006. The control-value theory of achievement emotions: Assumptions, corollaries, and implications for educational research and practice. Educ Psychol Rev 18:315-341.). Next, we distinguish between different types of achievement emotions, their proximal causes, and their consequences for motivation, learning, and performance, and we discuss several implications for educational practice. Finally, we end with a call for more research on achievement emotions in medical education to facilitate our understanding of emotions and their impact on important educational outcomes.

  8. A Meta-Analysis of Self-Reported Achievement Goals and Nonself-Report Performance across Three Achievement Domains (Work, Sports, and Education)

    PubMed Central

    Van Yperen, Nico W.; Blaga, Monica; Postmes, Tom

    2014-01-01

    During the past three decades, the achievement goal approach to achievement motivation has emerged as an influential area of research, and is dedicated to understanding the reasons behind the individual’s drive to achieve competence and performance. However, the current literature on achievement goals is segmented rather than integrated. That is, citations across the three major and distinct achievement domains (work, education, and sports) are more the exception than the rule and similarities and differences between findings for the different achievement domains have yet to be tested. The purpose of the present study was to examine the relationships between self-reported achievement goals and nonself-report performance through meta-analysis, and the moderating potential of achievement domain. Identifying achievement domain as moderator improves our understanding to which contexts we can (not) generalize conclusions to, it helps to understand seemingly inconsistent findings, and opens avenues for future research on the underlying processes. Because the achievement goal (AG) measure used in a study is partially confounded with achievement domain, we examined the moderating role of this variable as well. Our findings suggest that – overall – approach goals (either mastery or performance) were associated positively with performance attainment, whereas avoidance goals (either mastery or performance) were associated negatively with performance attainment. These relationships were moderated by achievement domain. For example, relative to the education or work domain, in the sports domain, we did not observe negative correlations between avoidance goals and performance. The absence of statistical moderation due to AG measure suggests that the observed moderation of achievement domain cannot be explained by the AG measure utilized. We suggest further steps to integrate the achievement goal literature, and accordingly, to broaden and deepen understanding of

  9. A meta-analysis of self-reported achievement goals and nonself-report performance across three achievement domains (work, sports, and education).

    PubMed

    Van Yperen, Nico W; Blaga, Monica; Postmes, Tom

    2014-01-01

    During the past three decades, the achievement goal approach to achievement motivation has emerged as an influential area of research, and is dedicated to understanding the reasons behind the individual's drive to achieve competence and performance. However, the current literature on achievement goals is segmented rather than integrated. That is, citations across the three major and distinct achievement domains (work, education, and sports) are more the exception than the rule and similarities and differences between findings for the different achievement domains have yet to be tested. The purpose of the present study was to examine the relationships between self-reported achievement goals and nonself-report performance through meta-analysis, and the moderating potential of achievement domain. Identifying achievement domain as moderator improves our understanding to which contexts we can (not) generalize conclusions to, it helps to understand seemingly inconsistent findings, and opens avenues for future research on the underlying processes. Because the achievement goal (AG) measure used in a study is partially confounded with achievement domain, we examined the moderating role of this variable as well. Our findings suggest that - overall - approach goals (either mastery or performance) were associated positively with performance attainment, whereas avoidance goals (either mastery or performance) were associated negatively with performance attainment. These relationships were moderated by achievement domain. For example, relative to the education or work domain, in the sports domain, we did not observe negative correlations between avoidance goals and performance. The absence of statistical moderation due to AG measure suggests that the observed moderation of achievement domain cannot be explained by the AG measure utilized. We suggest further steps to integrate the achievement goal literature, and accordingly, to broaden and deepen understanding of performance

  10. A comparison of Nannochloropsis salina growth performance in two outdoor pond designs: conventional raceways versus the ARID pond with superior temperature management

    SciTech Connect

    Crowe, Braden J.; Attalah, Said; Agrawal, Shweta; Waller, Peter; Ryan, Randy; Van Wagenen, Jonathan M.; Chavis, Aaron R.; Kyndt, John; Kacira, Murat; Ogden, Kimberly L.; Huesemann, Michael H.

    2012-10-01

    The present study examines how climatic conditions and pond design affect the growth performance of microalgae. From January to April of 2011, outdoor batch cultures of Nannochloropsis salina were grown in three replicate 780 L conventional raceways, as well as in an experimental 7500 L ARID (Algae Raceway Integrated Design) pond. The ARID culture system utilizes a series of 8 to 20 cm deep basins and a 1.5 m deep canal to enhance light exposure and mitigate temperature variations and extremes. The ARID culture reached the stationary phase 27 days earlier than the conventional raceways, which can be attributed to its superior temperature management and shallower basins. On a night when the air temperature dropped to -9 °C, the water temperature was 18 °C higher in the ARID pond than in the conventional raceways. Lipid and fatty acid content ranged from 16 - 25 % and 5 - 15 %, respectively, as a percentage of AFDW. Palmitic, palmitoleic, and eicosapentaenoic acid comprised the majority of fatty acids. While the ARID culture system achieved nearly double the volumetric productivity relative to the conventional raceways (0.023 vs 0.013 g L-1day-1), areal biomass productivities were of similar magnitude in both pond systems (3.34 vs. 3.47 g m-2day-1), suggesting that the ARID pond design has to be further optimized, most likely by increasing the culture depth or operating at higher cell densities while maintaining adequate mixing.

  11. Prediction of intrinsic motivation and sports performance using 2 x 2 achievement goal framework.

    PubMed

    Li, Chiung-Huang; Chi, Likang; Yeh, Suh-Ruu; Guo, Kwei-Bin; Ou, Cheng-Tsung; Kao, Chun-Chieh

    2011-04-01

    The purpose of this study was to examine the influence of 2 x 2 achievement goals on intrinsic motivation and performance in handball. Participants were 164 high school athletes. All completed the 2 x 2 Achievement Goals Questionnaire for Sport and the Intrinsic Motivation subscale of the Sport Motivation Scale; the coach for each team rated his athletes' overall sports performance. Using simultaneous-regression analyses, mastery-approach goals positively predicted both intrinsic motivation and performance in sports, whereas performance-avoidance goals negatively predicted sports performance. These results suggest that athletes who pursue task mastery and improvement of their competence perform well and enjoy their participation. In contrast, those who focus on avoiding normative incompetence perform poorly.

  12. Universal Factors of Student Achievement in High-Performing Eastern and Western Countries

    ERIC Educational Resources Information Center

    Lee, Jihyun

    2014-01-01

    This study investigates whether a common set of student attitudes and behavioral tendencies can account for academic achievement across different, especially high-performing, countries via analysis of the PISA 2009 international data set. The 13 countries examined are 5 of the top-performing Eastern countries/systems, namely Shanghai China, South…

  13. 39 CFR 3055.31 - Contents of the Quarterly Report of service performance achievements.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 39 Postal Service 1 2011-07-01 2011-07-01 false Contents of the Quarterly Report of service performance achievements. 3055.31 Section 3055.31 Postal Service POSTAL REGULATORY COMMISSION PERSONNEL SERVICE PERFORMANCE AND CUSTOMER SATISFACTION REPORTING Periodic Reporting of Service...

  14. The Effects of the Classroom Performance System on Student Participation, Attendance, and Achievement

    ERIC Educational Resources Information Center

    Termos, Mohamad Hani

    2013-01-01

    The Classroom Performance System (CPS) is an instructional technology that increases student performance and promotes active learning. This study assessed the effect of the CPS on student participation, attendance, and achievement in multicultural college-level anatomy and physiology classes, where students' first spoken language is not…

  15. Bottom-up SiO2 embedded carbon nanotube electrodes with superior performance for integration in implantable neural microsystems.

    PubMed

    Musa, Silke; Rand, Danielle R; Cott, Daire J; Loo, Josine; Bartic, Carmen; Eberle, Wolfgang; Nuttin, Bart; Borghs, Gustaaf

    2012-06-26

    The reliable integration of carbon nanotube (CNT) electrodes in future neural probes requires a proper embedding of the CNTs to prevent damage and toxic contamination during fabrication and also to preserve their mechanical integrity during implantation. Here we describe a novel bottom-up embedding approach where the CNT microelectrodes are encased in SiO(2) and Parylene C with lithographically defined electrode openings. Vertically aligned CNTs are grown on microelectrode arrays using low-temperature plasma-enhanced chemical vapor deposition compatible with wafer-scale CMOS processing. Electrodes with 5, 10, and 25 μm diameter are realized. The CNT electrodes are characterized by electrochemical impedance spectroscopy and cyclic voltammetry and compared against cofabricated Pt and TiN electrodes. The superior performance of the CNTs in terms of impedance (≤4.8 ± 0.3 kΩ at 1 kHz) and charge-storage capacity (≥513.9 ± 61.6 mC/cm(2)) is attributed to an increased wettability caused by the removal of the SiO(2) embedding in buffered hydrofluoric acid. Infrared spectroscopy reveals an unaltered chemical fingerprint of the CNTs after fabrication. Impedance monitoring during biphasic current pulsing with increasing amplitudes provides clear evidence of the onset of gas evolution at CNT electrodes. Stimulation is accordingly considered safe for charge densities ≤40.7 mC/cm(2). In addition, prolonged stimulation with 5000 biphasic current pulses at 8.1, 40.7, and 81.5 mC/cm(2) increases the CNT electrode impedance at 1 kHz only by 5.5, 1.2, and 12.1%, respectively. Finally, insertion of CNT electrodes with and without embedding into rat brains demonstrates that embedded CNTs are mechanically more stable than non-embedded CNTs. PMID:22551016

  16. Superior endurance performance of nonvolatile memory devices based on discrete storage in surface-nitrided Si nanocrystals

    NASA Astrophysics Data System (ADS)

    Yu, Jie; Chen, Kunji; Ma, Zhongyuan; Zhang, Xinxin; Jiang, Xiaofan; Huang, Xinfan; Zhang, Yongxing; Wang, Lingling

    2016-01-01

    The surface-nitrided silicon nanocrystals (Si-NCs) floating gate nonvolatile memory (NVM) devices were fabricated by 0.13 μm node CMOS technology. The surface-nitrided Si-NCs were formed in-situ by low-pressure chemical vapor deposition and followed by nitridation treatment in NH3 ambient. It is found that the nitridation treatment not only enhances the control effect of gate voltage on channel carriers by passivation of the Si-NCs surface defects but also suppresses releasing of the stored carriers among the neighboring Si-NCs and leakage from Si-NCs to channel through the tunneling oxide by a silicon nitride cover layer acted as potential barrier. Consequently, the storage carriers are fully discrete in the Si-NCs, which are different from that in the conventional poly-crystal Si or SONOS floating gate NVM devices. The surface-nitrided Si-NCs NVM devices show lower subthreshold swing value of 0.13 V/decade, faster P/E speed characteristics of 1 μs at ±7 V, and good retention characteristics at room temperature. Furthermore, due to the improvement of the tunneling oxide quality by nitridation treatment, the stable memory window of 1.7 V has been kept after 107 P/E cycles, showing superior endurance characteristics with the good retention characteristics. Our fabrication of surface-nitrided Si-NCs floating gate NVM is compatible with the standard CMOS technology, which may be employed in the 3-D NAND technology to further improve the device performance.

  17. Boasts are a boost: achievement prime self-reactivity predicts subsequent academic performance.

    PubMed

    Gramzow, Richard H; Johnson, Camille S; Willard, Greg

    2014-03-01

    The present research tests the hypothesis that self-reactivity following an achievement prime reflects the strength of achievement goals and is a predictor of future goal-relevant performance. In Studies 1-3, undergraduates reported their grade-point averages (GPAs) following either an achievement goal prime or a control prime. Academic exaggeration (higher self-reported than official GPA) was the indicator of self-reactivity to the prime. Study 1 involved a direct achievement goal prime, whereas Studies 2 and 3 involved indirect priming techniques. In all 3 experiments, greater academic exaggeration following the achievement goal prime (but not the control prime) predicted better academic performance a semester later (based on official records). Study 4 demonstrated that the magnitude of students' GPA goals mediated the association between academic exaggeration and subsequent performance (1 year later). The fact that self-reactivity to a single achievement goal prime in the lab predicted later performance in "real life" suggests that individual differences in reactivity to a specific prime can signal much broader motivational orientations related to the primed goal. PMID:24588092

  18. The impact of the achievement motive on athletic performance in adolescent football players.

    PubMed

    Zuber, Claudia; Conzelmann, Achim

    2014-01-01

    Researchers largely agree that there is a positive relationship between achievement motivation and athletic performance, which is why the achievement motive is viewed as a potential criterion for talent. However, the underlying mechanism behind this relationship remains unclear. In talent and performance models, main effect, mediator and moderator models have been suggested. A longitudinal study was carried out among 140 13-year-old football talents, using structural equation modelling to determine which model best explains how hope for success (HS) and fear of failure (FF), which are the aspects of the achievement motive, motor skills and abilities that affect performance. Over a period of half a year, HS can to some extent explain athletic performance, but this relationship is not mediated by the volume of training, sport-specific skills or abilities, nor is the achievement motive a moderating variable. Contrary to expectations, FF does not explain any part of performance. Aside from HS, however, motor abilities and in particular skills also predict a significant part of performance. The study confirms the widespread assumption that the development of athletic performance in football depends on multiple factors, and in particular that HS is worth watching in the medium term as a predictor of talent.

  19. A practice-specificity-based model of arousal for achieving peak performance.

    PubMed

    Movahedi, Ahmadreza; Sheikh, Mahmood; Bagherzadeh, Fazlolah; Hemayattalab, Rasool; Ashayeri, Hassan

    2007-11-01

    The authors propose a practice-specificity-based model of arousal for achieving peak performance. The study included 37 healthy male physical education students whom they randomly assigned to a high-arousal (n = 19) or low-arousal group (n = 18). To manipulate participants' level of arousal, the authors used motivational techniques. They used heart rate and the Sport Competition Anxiety Test (R. Martens, 1977) to measure the level of arousal that participants achieved. At the determined and given arousal state, the 2 groups performed the task (basketball free throws) for 18 sessions. Both groups performed a retention test at the 2 arousal levels immediately after the last exercise session, in the posttest, and after 10 days. Results showed that both groups learned the task similarly and achieved their peak performance at their experienced arousal level. When tested at an arousal level that differed from the one that they experienced throughout practice sessions, participants' performance had deteriorated significantly. Performance of the task seemed to have integrated with the arousal level of the participants during the task learning. The findings of this study suggest a practice-specificity-based explanation for achieving peak performance.

  20. Student Achievement for Whom? High-Performing and Still "Playing the Game," the Meaning of School Achievement among High Achieving African American Students

    ERIC Educational Resources Information Center

    Wiggan, Greg

    2014-01-01

    The preponderance of the research on African American students has generally focused on issues of school failure and underperformance. While the literature on high achieving Black students is sparse, very little is known about these students' school experiences and the meanings that they assign to achievement. Using student-based inquiry…

  1. Performance-based alternative assessments as a means of eliminating gender achievement differences on science tests

    NASA Astrophysics Data System (ADS)

    Brown, Norman Merrill

    1998-09-01

    Historically, researchers have reported an achievement difference between females and males on standardized science tests. These differences have been reported to be based upon science knowledge, abstract reasoning skills, mathematical abilities, and cultural and social phenomena. This research was designed to determine how mastery of specific science content from public school curricula might be evaluated with performance-based assessment models, without producing gender achievement differences. The assessment instruments used were Harcourt Brace Educational Measurement's GOALSsp°ler: A Performance-Based Measure of Achievement and the performance-based portion of the Stanford Achievement Testspcopyright, Ninth Edition. The identified independent variables were test, gender, ethnicity, and grade level. A 2 x 2 x 6 x 12 (test x gender x ethnicity x grade) factorial experimental design was used to organize the data. A stratified random sample (N = 2400) was selected from a national pool of norming data: N = 1200 from the GOALSsp°ler group and N = 1200 from the SAT9spcopyright group. The ANOVA analysis yielded mixed results. The factors of test, gender, ethnicity by grade, gender by grade, and gender by grade by ethnicity failed to produce significant results (alpha = 0.05). The factors yielding significant results were ethnicity, grade, and ethnicity by grade. Therefore, no significant differences were found between female and male achievement on these performance-based assessments.

  2. Predicting subjective vitality and performance in sports: the role of passion and achievement goals.

    PubMed

    Li, Chiung-Huang

    2010-06-01

    The major purpose of this study was to test the hypothesized paths from dualistic passions through achievement goals to subjective vitality and performance in sports. 645 high school athletes participated. The proposed structural equation model, with relationships between dualistic passions and subjective vitality and sports performance mediated by achievement goals, fit the data well, especially for mastery-approach and performance-approach goals. Harmonious and obsessive passions may lead athletes to high performance via the adoption of mastery-approach goals. However, these passions seem to have two paths influencing personal functioning: direct effects make players feel energetic, and indirect effects on subjective vitality through adoption of mastery-approach and performance-approach goals.

  3. Achievement goals, task performance, and interest: why perceived goal difficulty matters.

    PubMed

    Senko, Corwin; Harackiewicz, Judith M

    2005-12-01

    In field studies, mastery goals, which focus on developing skill, often predict task interest but not actual performance. Performance-approach goals, which focus on outperforming others, instead often predict strong performance but not interest. Two experiments tested the hypothesis that these distinct goal effects trace to goal difficulty perceptions. In each study, participants assigned to a performance-approach goal perceived their goal to be harder, and therefore felt more performance pressure, than those assigned to a mastery goal. Among participants low in dispositional achievement orientation, this experience translated into lower task interest when pursuing the performance-approach goal. However, participants in both studies also performed the activity better when pursuing this goal instead of a standard mastery goal, although this was not mediated by self-reported goal difficulty perceptions. Finally, further demonstrating the role of goal difficulty, a mastery goal manipulated to appear more difficult than a standard mastery goal produced effects matching the performance-approach goal.

  4. Performance on large-scale science tests: Item attributes that may impact achievement scores

    NASA Astrophysics Data System (ADS)

    Gordon, Janet Victoria

    Significant differences in achievement among ethnic groups persist on the eighth-grade science Washington Assessment of Student Learning (WASL). The WASL measures academic performance in science using both scenario and stand-alone question types. Previous research suggests that presenting target items connected to an authentic context, like scenario question types, can increase science achievement scores especially in underrepresented groups and thus help to close the achievement gap. The purpose of this study was to identify significant differences in performance between gender and ethnic subgroups by question type on the 2005 eighth-grade science WASL. MANOVA and ANOVA were used to examine relationships between gender and ethnic subgroups as independent variables with achievement scores on scenario and stand-alone question types as dependent variables. MANOVA revealed no significant effects for gender, suggesting that the 2005 eighth-grade science WASL was gender neutral. However, there were significant effects for ethnicity. ANOVA revealed significant effects for ethnicity and ethnicity by gender interaction in both question types. Effect sizes were negligible for the ethnicity by gender interaction. Large effect sizes between ethnicities on scenario question types became moderate to small effect sizes on stand-alone question types. This indicates the score advantage the higher performing subgroups had over the lower performing subgroups was not as large on stand-alone question types compared to scenario question types. A further comparison examined performance on multiple-choice items only within both question types. Similar achievement patterns between ethnicities emerged; however, achievement patterns between genders changed in boys' favor. Scenario question types appeared to register differences between ethnic groups to a greater degree than stand-alone question types. These differences may be attributable to individual differences in cognition

  5. Quantitative Guidance for Stove Usage and Performance to Achieve Health and Environmental Targets

    PubMed Central

    Chiang, Ranyee A.

    2015-01-01

    Background Displacing the use of polluting and inefficient cookstoves in developing countries is necessary to achieve the potential health and environmental benefits sought through clean cooking solutions. Yet little quantitative context has been provided on how much displacement of traditional technologies is needed to achieve targets for household air pollutant concentrations or fuel savings. Objectives This paper provides instructive guidance on the usage of cooking technologies required to achieve health and environmental improvements. Methods We evaluated different scenarios of displacement of traditional stoves with use of higher performing technologies. The air quality and fuel consumption impacts were estimated for these scenarios using a single-zone box model of indoor air quality and ratios of thermal efficiency. Results Stove performance and usage should be considered together, as lower performing stoves can result in similar or greater benefits than a higher performing stove if the lower performing stove has considerably higher displacement of the baseline stove. Based on the indoor air quality model, there are multiple performance–usage scenarios for achieving modest indoor air quality improvements. To meet World Health Organization guidance levels, however, three-stone fire and basic charcoal stove usage must be nearly eliminated to achieve the particulate matter target (< 1–3 hr/week), and substantially limited to meet the carbon monoxide guideline (< 7–9 hr/week). Conclusions Moderate health gains may be achieved with various performance–usage scenarios. The greatest benefits are estimated to be achieved by near-complete displacement of traditional stoves with clean technologies, emphasizing the need to shift in the long term to near exclusive use of clean fuels and stoves. The performance–usage scenarios are also provided as a tool to guide technology selection and prioritize behavior change opportunities to maximize impact. Citation

  6. Performance-Approach Goal Effects on Achievement under Low versus High Challenge Conditions

    ERIC Educational Resources Information Center

    Senko, Corwin; Durik, Amanda M.; Patel, Lily; Lovejoy, Chelsea M.; Valentiner, David

    2013-01-01

    Two studies examined the effects of university students' achievement goals on performance under low versus high challenge conditions. The first was a laboratory experiment in which participants were assigned goals to pursue on a novel mathematics task alleged to be simple or complex to use. The second was a survey study in which students set goals…

  7. Immigrant Children's Educational Achievement in Western Countries: Origin, Destination, and Community Effects on Mathematical Performance

    ERIC Educational Resources Information Center

    Levels, Mark; Dronkers, Jaap; Kraaykamp, Gerbert

    2008-01-01

    This article explores the extent to which macro-level characteristics of destination countries, origin countries, and immigrant communities help explain differences in immigrant children's educational achievement. Using data from the 2003 PISA survey, we analyze the mathematical performance of 7,403 pupils from 35 different origin countries in 13…

  8. Relationships Among Simple Measures of Reading and Performance on Standardized Achievement Tests.

    ERIC Educational Resources Information Center

    Deno, Stanley L.; And Others

    Three concurrent validity studies were conducted to determine the relationship between performances on formative measures of reading and standardized achievement measures of reading. Correlational analyses for five formative measures and three standardized measures provided evidence for the validity of Words in Isolation, Words in Context, and…

  9. Improving Achievement in Low-Performing Schools: Key Results for School Leaders

    ERIC Educational Resources Information Center

    Ward, Randolph E.; Burke, Mary Ann

    2004-01-01

    As accountability in schools becomes more crucial, educators are looking for comprehensive and innovative management practices that respond to challenges and realities of student academic achievement. In order to improve academic performance and the quality of instruction, the entire school community needs to be involved. This book provides six…

  10. Academic Performance in African American Undergraduates: Effects of Cultural Mistrust, Educational Value, and Achievement Motivation

    ERIC Educational Resources Information Center

    Caldwell, Taisha; Obasi, Ezemenari M.

    2010-01-01

    The current study examined achievement motivation, the value of education, cultural mistrust, and academic performance in 202 African American college students attending both Historically Black Colleges and Universities (HBCUs) and a Predominately White Institution (PWI). Results using hierarchical multiple regression established that the three…

  11. Gender, Geographic Locations, Achievement Goals and Academic Performance of Secondary School Students from Borno State, Nigeria

    ERIC Educational Resources Information Center

    Musa, Alice K.J.

    2013-01-01

    The paper examined gender, geography location, achievement goals and academic performance of senior secondary school students in Borno State, Nigeria. The sample consists of 827 students from 18 public boarding secondary schools across South and North of Borno State: 414 (50.1 per cent) males and 413 (49.9 per cent) are females; 414 (50.1 per…

  12. Reading Achievement, Mastery, and Performance Goal Structures among Students with Learning Disabilities: A Nonlinear Perspective

    ERIC Educational Resources Information Center

    Sideridis, Georgios D.; Stamovlasis, Dimitrios; Antoniou, Faye

    2016-01-01

    The purpose of the present study was to examine the hypothesis that a nonlinear relationship exists between a performance-classroom climate and the reading achievement of adolescent students with learning disabilities (LD). Participants were 62 students with LD (Grades 5-9) from public elementary schools in northern Greece. Classroom climate was…

  13. Four Language Skills Performance, Academic Achievement, and Learning Strategy Use in Preservice Teacher Training Programs

    ERIC Educational Resources Information Center

    Shawer, Saad Fathy

    2016-01-01

    This article examines the differences in language learning strategies (LLS) use between preservice teachers of English as a foreign language (EFL) and Arabic as a second language (ASL). It also examines the relationship between LLS use and language performance (academic achievement and four language skills) among ASL students. The study made use…

  14. Performance Concern, Contingent Self-Worth, and Responses to Repeated Achievement Failure in Second Graders

    ERIC Educational Resources Information Center

    Smiley, Patricia A.; Coulson, Sheri L.; Greene, Joelle K.; Bono, Katherine L.

    2010-01-01

    Individual differences in emotion, cognitions, and task choice following achievement failure are found among four- to seven-year-olds. However, neither performance deterioration during failure nor generalization after failure--aspects of the helpless pattern in 10-year-olds--have been reliably demonstrated in this age group. In the present study,…

  15. Teaching to the Tails: Teacher Performance Pay and the Distribution of Student Achievement

    ERIC Educational Resources Information Center

    Loyalka, Prashant; Sylvia, Sean; Liu, Chengfang; Chu, James; Rozelle, Scott

    2015-01-01

    Growing evidence suggests that teachers in developing countries often have weak or misaligned incentives for improving student outcomes. In response, policymakers and researchers have proposed performance pay as a way to improve student outcomes by tying concrete measures like achievement scores to teacher pay. While evidence from randomized…

  16. Marked for Success: Secondary School Performance and University Achievement in Biology

    ERIC Educational Resources Information Center

    Comer, Keith; Broght, Erik; Sampson, Kaylene

    2011-01-01

    Building on Shulruf, Hattie and Tumen (2008), this work examines the capacity of various National Certificate in Educational Achievement (NCEA)-derived models to predict first-year performance in Biological Sciences at a New Zealand university. We compared three models: (1) the "best-80" indicator as used by several New Zealand…

  17. Setting Student Performance Standards: The Role of Achievement Level Descriptions in the Standard Setting Process.

    ERIC Educational Resources Information Center

    Bourque, Mary Lyn

    This paper looks at using descriptions of subject matter content to assist in the development and interpretation of student performance on the National Assessment of Educational Progress (NAEP). These descriptions of content, called achievement level descriptions (ALDs), were initially conceptualized as exemplary statements of the knowledge and…

  18. Expressing International Educational Achievement in Terms of U.S. Performance Standards: Linking NAEP Achievement Levels to TIMSS

    ERIC Educational Resources Information Center

    Phillips, Gary W.

    2007-01-01

    Educators, researchers, and policymakers have considerable interest in how the American educational system compares to those in other countries. One major index for comparison is student academic achievement. This paper links the scale of the "National Assessment of Educational Progress" ("NAEP") to the scale of the "Third International…

  19. A Comparison of Nannochloropsis salina Growth Performance in Two Outdoor Pond Designs: Conventional Raceways versus the ARID Pond with Superior Temperature Management

    SciTech Connect

    Crowe, Braden; Attalah, Said; Agrawal, Shweta; Waller, Peter; Ryan, Randy; Van Wagenen, Jon; Chavis, Aaron; Kyndt, John; Kacira, Murat; Ogden, Kim L.; Huesemann, Michael

    2012-01-01

    The present study examines how climatic conditions and pond design affect the growth performance of microalgae. From January to April of 2011, outdoor batch cultures of Nannochloropsis salina were grown in three replicate 780 L conventional raceways, as well as in an experimental 7500 L algae raceway integrated design (ARID) pond. The ARID culture system utilizes a series of 8-20 cm deep basins and a 1.5 m deep canal to enhance light exposure and mitigate temperature variations and extremes. The ARID culture reached the stationary phase 27 days earlier than the conventional raceways, which can be attributed to its superior temperature management and shallower basins. On a night when the air temperature dropped to -9°C, the water temperature was 18°C higher in the ARID pond than in the conventional raceways. Lipid and fatty acid content ranged from 16 to 25% and from 5 to15%, respectively, as a percentage of AFDW. Palmitic, palmitoleic, and eicosapentaenoic acids comprised the majority of fatty acids. While the ARID culture system achieved nearly double the volumetric productivity relative to the conventional raceways (0.023 versus 0.013 g L-1day-1), areal biomass productivities were of similar magnitude in both pond systems (3.47 versus 3.34 g m-2day-1), suggesting that the ARID pond design has to be further optimized, most likely by increasing the culture depth or operating at higher cell densities while maintaining adequate mixing.

  20. Comparing standardized measures of diligence and achievement with dental student academic performance.

    PubMed

    Jedrychowski, Joseph; Lindemann, Robert

    2005-04-01

    Utilizing a reliable and valid instrument to measure a student's application of energy and effort towards a goal (diligence) or the ability to reach goals (achievement) would enable dental educators to anticipate academic performance. This knowledge could be used to better distribute faculty and educational resources, as additional tutors could be provided for students who score low on diligence and achievement instruments. In this study, fourth-year dental students completed the Diligence Inventory and the NachNaff Scale (which measures desire to achieve) immediately prior to graduation. The scores from both inventories were correlated with nine measures of academic performance. For males, the NachNaff Scale positively correlated (p<.05) only with the quantity of exceptional performance reports (EPR) and for females negatively correlated only with science DAT scores. The modest positive correlations, which differ for gender, suggest that the NachNaff may be of limited use to predict dental student performance. For males, the Total Diligence mean positively correlated with EPR and National Board Parts I and II scores. For females, the Total Diligence mean positively correlated with EPR and a predental biology-chemistry-physics grade composite. Given the simplicity of the Diligence Inventory and its significant correlations with academic performance demonstrated in this study, it appears to be a useful tool to gain insight into students' diligence in striving to obtain goals.

  1. The honeymoon effect in job performance - Temporal increases in the predictive power of achievement motivation

    NASA Technical Reports Server (NTRS)

    Helmreich, Robert L.; Sawin, Linda L.; Carsrud, Alan L.

    1986-01-01

    Correlations between a job performance criterion and personality measures reflecting achievement motivation and an interpersonal orientation were examined at three points in time after completion of job training for a sample of airline reservations agents. Although correlations between the personality predictors and performance were small and nonsignificant for the 3-month period after beginning the job, by the end of six and eight months a number of significant relationships had emerged. Implications for the utility of personality measures in selection and performance prediction are discussed.

  2. How to achieve performance portable code using OpenACC compiler directives?

    NASA Astrophysics Data System (ADS)

    Lapillonne, Xavier; Fuhrer, Oliver

    2014-05-01

    In view of adapting the weather and climate model COSMO to future architectures a new version of the model capable of running on graphics processing units (GPUs) has been developed. A large part of the code has been ported using compiler directives based on the OpenACC programming model. In order to achieve the best performance on GPUs several optimizations have been introduced for time critical components, mostly in the so-called physical parameterizations. Some of these modifications unfortunately degrade performance on traditional CPUs. Being a large community code, the COSMO model is required to perform well on both hybrid and CPU-only supercomputers. The current practical solution is to have separate source files for GPU and CPU execution, which may in the long-term result in maintenance issues. Considering the physical parameterization responsible for the atmospheric radiative transfer computations, we first present the restructuring techniques necessary to achieve performance on the GPU. We then show that some parts of the code are compute bound on the CPU while memory bound limited on the GPU, leading to different requirements in terms of optimization. We finally discuss various solutions to achieve a portable and maintainable code, both in terms of possible improvement of the OpenACC standard or in terms of programming strategy.

  3. Daily Online Testing in Large Classes: Boosting College Performance while Reducing Achievement Gaps

    PubMed Central

    Pennebaker, James W.; Gosling, Samuel D.; Ferrell, Jason D.

    2013-01-01

    An in-class computer-based system, that included daily online testing, was introduced to two large university classes. We examined subsequent improvements in academic performance and reductions in the achievement gaps between lower- and upper-middle class students in academic performance. Students (N = 901) brought laptop computers to classes and took daily quizzes that provided immediate and personalized feedback. Student performance was compared with the same data for traditional classes taught previously by the same instructors (N = 935). Exam performance was approximately half a letter grade above previous semesters, based on comparisons of identical questions asked from earlier years. Students in the experimental classes performed better in other classes, both in the semester they took the course and in subsequent semester classes. The new system resulted in a 50% reduction in the achievement gap as measured by grades among students of different social classes. These findings suggest that frequent consequential quizzing should be used routinely in large lecture courses to improve performance in class and in other concurrent and subsequent courses. PMID:24278176

  4. The effects of achievement goals on performance, enjoyment, and practice of a novel motor task.

    PubMed

    Kavussanu, Maria; Morris, Rebecca L; Ring, Christopher

    2009-10-01

    We examined the effects of trichotomous achievement goals on performance, enjoyment, and practice of a golf-putting task. Male (n = 39) and female (n = 63) undergraduate students participated in the experiment in exchange for course credit. Participants were assigned to a mastery, performance-approach, or performance-avoidance goal condition and completed seven blocks of 10 trials (one for baseline, four for the experimental phase, and two for the transfer phase) of a golf-putting task. Distance from the target was measured and performance measures of accuracy and consistency were calculated. Self-reported enjoyment during the baseline and experimental phases and practice during a 5-min period before and following the experimental task were also assessed. Performance accuracy and consistency improved similarly among the three groups. Individuals in all three conditions reported enjoying the task to the same extent. Mastery participants practiced for longer than performance-approach participants during the practice period. Performance-avoidance participants did not differ significantly from the other two groups. The three goals were equally effective in promoting performance and enjoyment of the golf-putting task. The differential practice results for the two performance goals suggest that they should be considered separately. PMID:19735037

  5. The effect of workshop groups on achievement goals and performance in biology: An outcome evaluation

    NASA Astrophysics Data System (ADS)

    Born, Wendi Kay

    This two-year quasi-experiment evaluated the effect of peer-led workshop groups on performance of minority and majority undergraduate biology students in a three-course series and investigated motivational explanations for performance differences. The workshop intervention used was modeled after a program pioneered by Treisman (1992) at the University of California. Majority volunteers randomly assigned to workshops (n = 61) performed between 1/2 and 1 standard deviation better than those assigned to the control group (n = 60; p < .05) in each quarter without spending more time studying. During Quarter 1, workshop minority students (n = 25) showed a pattern of increasing exam performance in comparison to historic control minority students (n = 21), who showed a decreasing pattern (p < .05). Although sex differences in biology performance were a focus of investigation, none were detected. Motivational predictions derived from the hierarchical model of approach and avoidance achievement motivation (Elliot & Church, 1997) were partially supported. Self-report survey measures of achievement goals, modeled after those used by Elliot and colleagues, were requested from all enrolled students. Volunteers (n = 121) reported higher average levels of approach and avoidance goals than nonvolunteers (n = 439; p < .05) and the relationship of goals to performance was moderated by volunteer status. Performance of volunteers was negatively related to avoidance of failure goals (r = .41, p < .01) and unrelated to performance approach goals. Performance of nonvolunteers was unrelated to avoidance of failure goals and positively related to performance approach goals (r = .28, p < .01). Mastery goals were unrelated to performance for all students. Results were inconsistent with Dweck and Leggett's (1988) theory of mastery vs. performance orientation, but were similar to results found by Elliot and colleagues. Contrary to hypotheses, motivational goals did not mediate performance for

  6. Social jetlag, academic achievement and cognitive performance: Understanding gender/sex differences.

    PubMed

    Díaz-Morales, Juan F; Escribano, Cristina

    2015-01-01

    Adolescents in high school suffer from circadian misalignment, undersleeping on weekdays and oversleeping on weekends. Since high schools usually impose early schedules, adolescents suffer from permanent social jetlag (SJL) and thus are a suitable population to study the effects of SJL on both academic and cognitive performance. In this study, 796 adolescents aged 12-16 years reported information about their sleep habits, morningness-eveningness (M-E), cognitive abilities and grade point average (GPA). Time in bed on both weekdays and weekends was not related to cognitive abilities, and only time in bed on weekdays was related to academic achievement. SJL was negatively related to academic achievement, cognitive abilities (except for vocabulary and verbal fluency abilities) and general cognitive ability (g), whereas M-E was slightly positively related to academic achievement and marginally negatively related to inductive reasoning. Results separated by sex/gender indicated that SJL may be more detrimental to girls' performance, as it was negatively related to a greater number of cognitive abilities and GPA.

  7. FeS anchored reduced graphene oxide nanosheets as advanced anode material with superior high-rate performance for alkaline secondary batteries

    NASA Astrophysics Data System (ADS)

    Shangguan, Enbo; Guo, Litan; Li, Fei; Wang, Qin; Li, Jing; Li, Quanmin; Chang, Zhaorong; Yuan, Xiao-Zi

    2016-09-01

    A new nanocomposite formulation of the iron-based anode for alkaline secondary batteries is proposed. For the first time, FeS nanoparticles anchored on reduced graphene oxide (RGO) nanosheets are synthesized via a facile, environmentally friendly direct-precipitation approach. In this nanocomposite, FeS nanoparticles are anchored uniformly and tightly on the surface of RGO nanosheets. As an alkaline battery anode, the FeS@RGO electrode delivers a superior high-rate charge/discharge capability and outstanding cycling stability, even at a condition without any conductive additives and a high electrode loading of ∼40 mg cm-2. At high charge/discharge rates of 5C, 10C and 20C (6000 mA g-1), the FeS@RGO electrode presents a specific capacity of ∼288, 258 and 220 mAh g-1, respectively. Moreover, the FeS@RGO electrode exhibits an admirable long cycling stability with a superior capacity retention of 87.6% for 300 cycles at a charge/discharge rate of 2C. The excellent electrochemical properties of the FeS@RGO electrode can be stemmed from the high specific surface area, peculiar electric conductivity and robust sheet-anchored structure of the FeS@RGO nanocomposite. By virtue of its superior fast charge/discharge properties, the FeS@RGO nanocomposite is suitable as an advanced anode material for high-performance alkaline secondary batteries.

  8. A Green Synthesis of Nanosheet-Constructed Pd Particles in an Ionic Liquid and Their Superior Electrocatalytic Performance.

    PubMed

    Zhang, Baohua; Xue, Yiguo; Xue, Zhimin; Li, Zhonghao; Hao, Jingcheng

    2015-12-21

    The ionic liquid 1-ethyl-3-methylimidazolium acetate ([EMIM]Ac) is investigated as a solvent for the synthesis of Pd particles. Interestingly, nanosheet-constructed Pd particles could be successfully synthesized in [EMIM]Ac without any additional reducing agent and template under ionothermal conditions. [EMIM]Ac itself works as the solvent, the reducing agent, and the template for the formation of these interesting Pd particles, making this method complementary to the well-known ionic-liquid-precursor approach. Furthermore, [EMIM]Ac can be recycled with no loss of activity for the formation of nanosheet-constructed Pd particles within our studied cycles. Specifically, the nanosheet-constructed Pd particles exhibit superior electrocatalytic activity and stability towards ethanol oxidation and formic acid oxidation compared with commercially available Pd black catalyst, thus demonstrating their promising applications in fuel-cell area. The current approach, thus, presents a green approach towards the synthesis of Pd particles, using only a simple palladium salt and an ionic liquid. PMID:26463254

  9. Superior intrinsic thermoelectric performance with zT of 1.8 in single-crystal and melt-quenched highly dense Cu(2-x)Se bulks.

    PubMed

    Zhao, Lan-ling; Wang, Xiao-lin; Wang, Ji-yang; Cheng, Zhen-xiang; Dou, Shi-xue; Wang, Jun; Liu, Li-qiang

    2015-01-08

    Practical applications of the high temperature thermoelectric materials developed so far are partially obstructed by the costly and complicated fabrication process. In this work, we put forward two additional important properties for thermoelectric materials, high crystal symmetry and congruent melting. We propose that the recently discovered thermoelectric material Cu2-xSe, with figure of merit, zT, over 1.5 at T of ~ 1000 K, should meet these requirements, based on our analysis of its crystal structure and the Cu-Se binary phase diagram. We found that its excellent thermoelectric performance is intrinsic, and less dependent on grain size, while highly dense samples can be easily fabricated by a melt-quenching approach. Our results reveal that the melt-quenched samples and single crystals exhibit almost the same superior thermoelectric performance, with zT as high as 1.7-1.8 at T of ~973 K. Our findings not only provide a cheap and fast fabrication method for highly dense Cu(2-x)Se bulks with superior thermoelectric performance, paving the way for possible commercialization of Cu2-xSe as an outstanding component in practical thermoelectric modules, but also provide guidance in searching for new classes of thermoelectric systems with high crystal symmetry or further improving the cost performance of other existing congruent-melting thermoelectric materials.

  10. High performances CNTFETs achieved using CNT networks for selective gas sensing

    NASA Astrophysics Data System (ADS)

    Gorintin, Louis; Bondavalli, Paolo; Legagneux, Pierre; Pribat, Didier

    2009-08-01

    Our study deals with the utilization of carbon nanotubes networks based transistors with different metal electrodes for highly selective gas sensing. Indeed, carbon nanotubes networks can be used as semi conducting materials to achieve good performances transistors. These devices are extremely sensitive to the change of the Schottky barrier heights between Single Wall Carbon Nanotubes (SWCNTs) and drain/source metal electrodes: the gas adsorption creates an interfacial dipole that modifies the metal work function and so the bending and the height of the Schottky barrier at the contacts. Moreover each gas interacts specifically with each metal identifying a sort of electronic fingerprinting. Using airbrush technique for deposition, we have been able to achieve uniform random networks of carbon nanotubes suitable for large area applications and mass production such as fabrication of CNT based gas sensors. These networks enable us to achieve transistors with on/off ratio of more than 5 orders of magnitude. To reach these characteristics, the density of the CNT network has been adjusted in order to reach the percolation threshold only for semi-conducting nanotubes. These optimized devices have allowed us to tune the sensitivity (improving it) of our sensors for highly selective detection of DiMethyl-Methyl-Phosphonate (DMMP, a sarin stimulant), and even volatile drug precursors using Pd, Au and Mo electrodes.

  11. Wind/tornado design criteria, development to achieve required probabilistic performance goals

    SciTech Connect

    Ng, D.S.

    1991-06-01

    This paper describes the strategy for developing new design criteria for a critical facility to withstand loading induced by the wind/tornado hazard. The proposed design requirements for resisting wind/tornado loads are based on probabilistic performance goals. The proposed design criteria were prepared by a Working Group consisting of six experts in wind/tornado engineering and meteorology. Utilizing their best technical knowledge and judgment in the wind/tornado field, they met and discussed the methodologies and reviewed available data. A review of the available wind/tornado hazard model for the site, structural response evaluation methods, and conservative acceptance criteria lead to proposed design criteria that has a high probability of achieving the required performance goals.

  12. Performance Achievements and Challenges for FELs based on Energy Recovered Linacs

    SciTech Connect

    Geoffrey Krafft

    2006-08-27

    During the past decade several groups have assembled free electron lasers based on energy recovered linacs (ERLs). Such arrangements have been built to obtain high average power electron and photon beams, by using high repetition rate beam pulses driving FEL oscillators. In this paper the performance of many existing and several proposed facilities from around the world are reviewed. Going forward, many questions must be addressed to achieve still better performance including: higher average current injectors, better optimized accelerating cavities, higher energy acceptance and lower loss beam recirculation systems, and better optical cavity designs for dealing with the optical beam power circulating in the ERL FELs. This paper presents some of the current thinking on each of these issues.

  13. Effectiveness of a refuge for lake trout in western Lake Superior I: Empirical analysis of past performance

    USGS Publications Warehouse

    Johnson, Melissa J.; Hansen, Michael J.; Seider, Michael J.

    2015-01-01

    The Gull Island Shoal Refuge was created in 1976 in response to overfishing of the Lake Trout Salvelinus namaycush population in the Apostle Islands region of western Lake Superior. Our objective was to evaluate effectiveness of the refuge by determining whether Lake Trout abundance, growth, maturity, and mortality differed inside and outside the refuge. We compared abundance of wild and stocked fish captured inside and outside the refuge during spring large-mesh gill-net and summer graded-mesh gill-net surveys. We compared growth and mortality during four periods corresponding to four generations of wild Lake Trout, including the last generation that hatched before the refuge was instituted (sampled in 1981–1984) and three generations that were protected by the refuge (sampled in 1985–1992, 1993–2000, and 2001–2010). Maturity of wild fish inside and outside the refuge was compared only for the latter period (2001–2010) because maturity was not assessed earlier. After the refuge was created, wild Lake Trout abundance increased and stocked Lake Trout abundance decreased. Wild adults and juveniles were more abundant inside than outside the refuge, and stocked adults were less abundant inside than outside the refuge. Growth of wild fish did not differ inside versus outside the refuge before 2001, but wild fish grew faster to a shorter asymptotic length inside than outside the refuge during 2001–2010. Wild fish matured at a similar length but an older age inside than outside the refuge during 2001–2010. Survival of wild fish did not differ inside versus outside the refuge before 1993, but mortality was lower inside than outside the refuge during later periods (1993–2000 and 2001–2010). We conclude that the Gull Island Shoal Refuge enhanced the population growth of wild Lake Trout in the Apostle Islands region and should be retained in the future to sustain conditions that favor population growth.

  14. HuCAL PLATINUM, a synthetic Fab library optimized for sequence diversity and superior performance in mammalian expression systems.

    PubMed

    Prassler, Josef; Thiel, Stefanie; Pracht, Catrin; Polzer, Andrea; Peters, Solveig; Bauer, Marion; Nörenberg, Stephanie; Stark, Yvonne; Kölln, Johanna; Popp, Andreas; Urlinger, Stefanie; Enzelberger, Markus

    2011-10-14

    This article describes the design of HuCAL (human combinatorial antibody library) PLATINUM, an optimized, second-generation, synthetic human Fab antibody library with six trinucleotide-randomized complementarity-determining regions (CDRs). Major improvements regarding the optimized antibody library sequence space were implemented. Sequence space optimization is considered a multistep process that includes the analysis of unproductive antibody sequences in order to, for example, avoid motifs such as potential N-glycosylation sites, which are undesirable in antibody production. Gene optimization has been used to improve expression of the antibody master genes in the library context. As a result, full-length IgGs derived from the library show both significant improvements in expression levels and less undesirable glycosylation sites when compared to the previous HuCAL GOLD library. Additionally, in-depth analysis of sequences from public databases revealed that diversity of CDR-H3 is a function of loop length. Based upon this analysis, the relatively uniform diversification strategy used in the CDR-H3s of the previous HuCAL libraries was changed to a length-dependent design, which replicates the natural amino acid distribution of CDR-H3 in the human repertoire. In a side-by-side comparison of HuCAL GOLD and HuCAL PLATINUM, the new library concept led to isolation of about fourfold more unique sequences and to a higher number of high-affinity antibodies. In the majority of HuCAL PLATINUM projects, 100-300 antibodies each having different CDR-H3s are obtained against each antigen. This increased diversity pool has been shown to significantly benefit functional antibody profiling and screening for superior biophysical properties.

  15. Evaluation of additional cooking procedures to achieve lethality microbiological performance standards for large, intact meat products.

    PubMed

    Haneklaus, A N; Harris, K B; Cuervo, M P; Ilhak, O I; Lucia, L M; Castillo, A; Hardin, M D; Osburn, W N; Savell, J W

    2011-10-01

    The U.S. Department of Agriculture Food Safety and Inspection Service (USDA-FSIS) has a specific lethality performance standard for ready-to-eat products. To assist meat processing establishments in meeting the performance standard, USDA-FSIS developed Appendix A, which provides guidelines for cooking temperatures, times, and relative humidity. This project determined whether the USDA-FSIS performance standards for lethality were met when using parameters other than those identified in Appendix A to cook large hams and beef inside rounds. The effects of alternative lethality parameters on the reduction of Salmonella Typhimurium and coliforms and on the toxin production of Staphylococcus aureus were evaluated. Large (9- to 12-kg) cured bone-in hams (n = 80) and large (8- to 13-kg) uncured beef inside rounds (n = 80) were used in this study. The products were subjected to 1 of 10 treatments defined by combinations of final internal product temperatures (48.9, 54.4, 60.0, 65.6, or 71.1°C) and batch oven relative humidities (50 or 90 % ). For all treatments, at least a 6.5-log reduction in Salmonella Typhimurium was achieved. The coliform counts were also substantially reduced for both hams and rounds. Across all treatments for both products, S. aureus toxin production was not detected. The relative humidity did not alter the lethality effectiveness for any of the treatments. The final internal temperatures and relative humidity combinations used in this project achieved the lethality performance standard established by USDA-FSIS for fully cooked, ready-to-eat products. PMID:22004824

  16. Achieving High Performance in AC-Field Driven Organic Light Sources

    PubMed Central

    Xu, Junwei; Carroll, David L.; Smith, Gregory M.; Dun, Chaochao; Cui, Yue

    2016-01-01

    Charge balance in organic light emitting structures is essential to simultaneously achieving high brightness and high efficiency. In DC-driven organic light emitting devices (OLEDs), this is relatively straight forward. However, in the newly emerging, capacitive, field-activated AC-driven organic devices, charge balance can be a challenge. In this work we introduce the concept of gating the compensation charge in AC-driven organic devices and demonstrate that this can result in exceptional increases in device performance. To do this we replace the insulator layer in a typical field-activated organic light emitting device with a nanostructured, wide band gap semiconductor layer. This layer acts as a gate between the emitter layer and the voltage contact. Time resolved device characterization shows that, at high-frequencies (over 40 kHz), the semiconductor layer allows for charge accumulation in the forward bias, light generating part of the AC cycle and charge compensation in the negative, quiescent part of the AC cycle. Such gated AC organic devices can achieve a non-output coupled luminance of 25,900 cd/m2 with power efficiencies that exceed both the insulator-based AC devices and OLEDs using the same emitters. This work clearly demonstrates that by realizing balanced management of charge, AC-driven organic light emitting devices may well be able to rival today’s OLEDs in performance. PMID:27063414

  17. Achieving High Performance in AC-Field Driven Organic Light Sources.

    PubMed

    Xu, Junwei; Carroll, David L; Smith, Gregory M; Dun, Chaochao; Cui, Yue

    2016-04-11

    Charge balance in organic light emitting structures is essential to simultaneously achieving high brightness and high efficiency. In DC-driven organic light emitting devices (OLEDs), this is relatively straight forward. However, in the newly emerging, capacitive, field-activated AC-driven organic devices, charge balance can be a challenge. In this work we introduce the concept of gating the compensation charge in AC-driven organic devices and demonstrate that this can result in exceptional increases in device performance. To do this we replace the insulator layer in a typical field-activated organic light emitting device with a nanostructured, wide band gap semiconductor layer. This layer acts as a gate between the emitter layer and the voltage contact. Time resolved device characterization shows that, at high-frequencies (over 40 kHz), the semiconductor layer allows for charge accumulation in the forward bias, light generating part of the AC cycle and charge compensation in the negative, quiescent part of the AC cycle. Such gated AC organic devices can achieve a non-output coupled luminance of 25,900 cd/m(2) with power efficiencies that exceed both the insulator-based AC devices and OLEDs using the same emitters. This work clearly demonstrates that by realizing balanced management of charge, AC-driven organic light emitting devices may well be able to rival today's OLEDs in performance.

  18. High-Achieving High School Students and Not so High-Achieving College Students: A Look at Lack of Self-Control, Academic Ability, and Performance in College

    ERIC Educational Resources Information Center

    Honken, Nora B.; Ralston, Patricia A. S.

    2013-01-01

    This study investigated the relationship among lack of self-control, academic ability, and academic performance for a cohort of freshman engineering students who were, with a few exceptions, extremely high achievers in high school. Structural equation modeling analysis led to the conclusion that lack of self-control in high school, as measured by…

  19. A Comparison of Performance in Solving Arithmetical Word Problems by Children with Different Levels of Achievement in Mathematics and Reading

    ERIC Educational Resources Information Center

    Reikeras, Elin K. L.

    2009-01-01

    Performance in consistent arithmetical word problems was assessed in 941 pupils aged eight (N = 415), ten (N = 274), and thirteen (N = 252) classified in four achievement groups by standardised achievement tests: low achievement in both mathematics and reading (MLRL), in mathematics only (ML-only), in reading only (RL-only), and normal achievement…

  20. On the achievable performance using variable geometry active secondary suspension systems in commercial vehicles

    NASA Astrophysics Data System (ADS)

    Evers, Willem-Jan; Besselink, Igo; Teerhuis, Arjan; Nijmeijer, Henk

    2011-10-01

    There is a need to further improve driver comfort in commercial vehicles. The variable geometry active suspension offers an interesting option to achieve this in an energy efficient way. However, the optimal control strategy and the overal performance potential remains unclear. The aim of this paper is to quantify the level of performance improvement that can theoretically be obtained by replacing a conventional air sprung cabin suspension design with a variable geometry active suspension. Furthermore, the difference between the use of a linear quadratic (LQ) optimal controller and a classic skyhook controller is investigated. Hereto, an elementary variable geometry actuator model and experimentally validated four degrees of freedom quarter truck model are adopted. The results show that the classic skyhook controller gives a relatively poor performance while a comfort increase of 17-28% can be obtained with the LQ optimal controller, depending on the chosen energy weighting. Furthermore, an additional 75% comfort increase and 77% energy cost reduction can be obtained, with respect to the fixed gain energy optimal controller, using condition-dependent control gains. So, it is concluded that the performance potential using condition-dependent controllers is huge, and that the use of the classic skyhook control strategy should, in general, be avoided when designing active secondary suspensions for commercial vehicles.

  1. Achieving realistic performance and decison-making capabilities in computer-generated air forces

    NASA Astrophysics Data System (ADS)

    Banks, Sheila B.; Stytz, Martin R.; Santos, Eugene, Jr.; Zurita, Vincent B.; Benslay, James L., Jr.

    1997-07-01

    For a computer-generated force (CGF) system to be useful in training environments, it must be able to operate at multiple skill levels, exhibit competency at assigned missions, and comply with current doctrine. Because of the rapid rate of change in distributed interactive simulation (DIS) and the expanding set of performance objectives for any computer- generated force, the system must also be modifiable at reasonable cost and incorporate mechanisms for learning. Therefore, CGF applications must have adaptable decision mechanisms and behaviors and perform automated incorporation of past reasoning and experience into its decision process. The CGF must also possess multiple skill levels for classes of entities, gracefully degrade its reasoning capability in response to system stress, possess an expandable modular knowledge structure, and perform adaptive mission planning. Furthermore, correctly performing individual entity behaviors is not sufficient. Issues related to complex inter-entity behavioral interactions, such as the need to maintain formation and share information, must also be considered. The CGF must also be able to acceptably respond to unforeseen circumstances and be able to make decisions in spite of uncertain information. Because of the need for increased complexity in the virtual battlespace, the CGF should exhibit complex, realistic behavior patterns within the battlespace. To achieve these necessary capabilities, an extensible software architecture, an expandable knowledge base, and an adaptable decision making mechanism are required. Our lab has addressed these issues in detail. The resulting DIS-compliant system is called the automated wingman (AW). The AW is based on fuzzy logic, the common object database (CODB) software architecture, and a hierarchical knowledge structure. We describe the techniques we used to enable us to make progress toward a CGF entity that satisfies the requirements presented above. We present our design and

  2. A comprehensive approach to decipher biological computation to achieve next generation high-performance exascale computing.

    SciTech Connect

    James, Conrad D.; Schiess, Adrian B.; Howell, Jamie; Baca, Michael J.; Partridge, L. Donald; Finnegan, Patrick Sean; Wolfley, Steven L.; Dagel, Daryl James; Spahn, Olga Blum; Harper, Jason C.; Pohl, Kenneth Roy; Mickel, Patrick R.; Lohn, Andrew; Marinella, Matthew

    2013-10-01

    The human brain (volume=1200cm3) consumes 20W and is capable of performing > 10^16 operations/s. Current supercomputer technology has reached 1015 operations/s, yet it requires 1500m^3 and 3MW, giving the brain a 10^12 advantage in operations/s/W/cm^3. Thus, to reach exascale computation, two achievements are required: 1) improved understanding of computation in biological tissue, and 2) a paradigm shift towards neuromorphic computing where hardware circuits mimic properties of neural tissue. To address 1), we will interrogate corticostriatal networks in mouse brain tissue slices, specifically with regard to their frequency filtering capabilities as a function of input stimulus. To address 2), we will instantiate biological computing characteristics such as multi-bit storage into hardware devices with future computational and memory applications. Resistive memory devices will be modeled, designed, and fabricated in the MESA facility in consultation with our internal and external collaborators.

  3. 3D Polyaniline Architecture by Concurrent Inorganic and Organic Acid Doping for Superior and Robust High Rate Supercapacitor Performance

    PubMed Central

    Gawli, Yogesh; Banerjee, Abhik; Dhakras, Dipti; Deo, Meenal; Bulani, Dinesh; Wadgaonkar, Prakash; Shelke, Manjusha; Ogale, Satishchandra

    2016-01-01

    A good high rate supercapacitor performance requires a fine control of morphological (surface area and pore size distribution) and electrical properties of the electrode materials. Polyaniline (PANI) is an interesting material in supercapacitor context because it stores energy Faradaically. However in conventional inorganic (e.g. HCl) acid doping, the conductivity is high but the morphological features are undesirable. On the other hand, in weak organic acid (e.g. phytic acid) doping, interesting and desirable 3D connected morphological features are attained but the conductivity is poorer. Here the synergy of the positive quality factors of these two acid doping approaches is realized by concurrent and optimized strong-inorganic (HCl) and weak-organic (phytic) acid doping, resulting in a molecular composite material that renders impressive and robust supercapacitor performance. Thus, a nearly constant high specific capacitance of 350 F g−1 is realized for the optimised case of binary doping over the entire range of 1 A g−1 to 40 A g−1 with stability of 500 cycles at 40 A g−1. Frequency dependant conductivity measurements show that the optimized co-doped case is more metallic than separately doped materials. This transport property emanates from the unique 3D single molecular character of such system. PMID:26867570

  4. Academic task persistence of normally achieving ADHD and control boys: performance, self-evaluations, and attributions.

    PubMed

    Hoza, B; Pelham, W E; Waschbusch, D A; Kipp, H; Owens, J S

    2001-04-01

    The authors examined academic task persistence, pretask expectancies, self-evaluations, and attributions of boys with attention-deficit/hyperactivity disorder (ADHD) as compared with control boys. Participants were 83 ADHD boys and 66 control boys, all normally achieving. Prior to the task, performance expectancies were assessed. After a success-failure manipulation with find-a-word puzzles, performance on subsequent trials, self-evaluations, and attributions were evaluated. Compared with controls, ADHD boys solved fewer test puzzles, quit working more often, and found fewer words on a generalization task. Consistent with these behavioral findings, research assistants rated ADHD boys as less effortful and less cooperative than control boys. Although ADHD boys did not differ significantly from controls in their posttask self-evaluations, they did differ significantly from controls in some aspects of their attributions. Attributional data indicated that ADHD boys endorsed luck as a reason for success more strongly and lack of effort as a reason for failure less strongly than controls. PMID:11393604

  5. Ultrathin Na1.1V3O7.9 nanobelts with superior performance as cathode materials for lithium-ion batteries.

    PubMed

    Liang, Shuquan; Zhou, Jiang; Fang, Guozhao; Liu, Jing; Tang, Yan; Li, Xilin; Pan, Anqiang

    2013-09-11

    The Na1.1V3O7.9 nanobelts have been synthesized by a facile and scalable hydrothermal reaction with subsequent calcinations. The morphologies and the crystallinity of the nanobelts are largely determined by the calcination temperatures. Ultrathin nanobelts with a thickness around 20 nm can be obtained, and the TEM reveals that the nanobelts are composed of many stacked thinner belts. When evaluated as a cathode material for lithium batteries, the Na1.1V3O7.9 nanobelts exhibit high specific capacity, good rate capability, and superior long-term cyclic stability. A high specific capacity of 204 mA h g(-1) can be delivered at the current density of 100 mA g(-1). It shows excellent capacity retention of 95% after 200 cycles at the current density of 1500 mA g(-1). As demonstrated by the ex situ XRD results, the Na1.1V3O7.9 nanobelts have very good structural stability upon cycling. The superior electrochemical performances can be attributed to the ultra-thin nanobelts and the good structural stability of the Na1.1V3O7.9 nanobelts.

  6. Superior performance of highly flexible solid-state supercapacitor based on the ternary composites of graphene oxide supported poly(3,4-ethylenedioxythiophene)-carbon nanotubes

    NASA Astrophysics Data System (ADS)

    Zhou, Haihan; Zhai, Hua-Jin; Han, Gaoyi

    2016-08-01

    Ternary composite electrodes based on carbon nanotubes thin films (CNFs)-loaded graphene oxide (GO) supported poly(3,4-ethylenedioxythiophene)- carbon nanotubes (GO/PEDOT-CNTs) have been prepared via a facile one-step electrochemical codeposition method. The effect of long and short CNTs-incorporated composites (GO/PEDOT-lCNTs and GO/PEDOT-sCNTs) on the electrochemical behaviors of the electrodes is investigated and compared. Electrochemical measurements indicate that the incorporation of CNTs effectively improves the electrochemical performances of the GO/PEDOT electrodes. Long CNTs-incorporated GO/PEDOT-lCNTs electrodes have more superior electrochemical behaviors with respect to the short CNTs-incorporated GO/PEDOT-lCNTs electrodes, which can be attributed to the optimized composition and specific microstructures of the former. To verify the feasibility of the prepared composite electrodes for utilization as flexible supercapacitor, a solid-state supercapacitor using the CNFs-loaded GO/PEDOT-lCNTs electrodes is fabricated and tested. The device shows lightweight, ultrathin, and highly flexible features, which also has a high areal and volumetric specific capacitance (33.4 m F cm-2 at 10 mV s-1 and 2.7 F cm-3 at 0.042 A cm-3), superior rate capability, and excellent cycle stability (maintaining 97.5% for 5000 cycles). This highly flexible solid-state supercapacitor has great potential for applications in flexible electronics, roll-up display, and wearable devices.

  7. Preparation of Novel Li4 SiO4 Sorbents with Superior Performance at Low CO2 Concentration.

    PubMed

    Yang, Xinwei; Liu, Wenqiang; Sun, Jian; Hu, Yingchao; Wang, Wenyu; Chen, Hongqiang; Zhang, Yang; Li, Xian; Xu, Minghou

    2016-07-01

    This work produced Li4 SiO4 sorbents through an impregnated-suspension method to overcome its typical poor performance at low CO2 concentrations. A SiO2 colloidal solution and two different organic lithium precursors were selected. A bulgy surface morphology (and thus, the significantly enlarged reacting surface area) was obtained for Li4 SiO4 , which contributed to the high absorption capacity. As a result, the capacity in cyclic tests at 15 vol % CO2 was approximately 8 times higher than conventional Li4 SiO4 prepared through a solid-state reaction. The phenomenon of a progressively increasing capacity (i.e., sustainable usage) was observed over the 40 cycles investigated, and this increasing trend continued to the last cycle. Correspondingly, over the course of the multicycle absorption/ desorption processes, the sorbents evolve from lacking porosity to having a high number of micron-sized pores.

  8. Performance Trajectories and Performance Gaps as Achievement Effect-Size Benchmarks for Educational Interventions. MDRC Working Papers on Research Methodology

    ERIC Educational Resources Information Center

    Bloom, Howard S.; Hill, Carolyn J.; Black, Alison Rebeck; Lipsey, Mark W.

    2008-01-01

    This paper explores two complementary approaches to developing empirical benchmarks for achievement effect sizes in educational interventions. The first approach characterizes the natural developmental progress in achievement by students from one year to the next as effect sizes. Data for seven nationally standardized achievement tests show large…

  9. The Achievement Motivation-Performance Relationship as Moderated by Sex-Role Attitudes

    ERIC Educational Resources Information Center

    Thurber, Steven

    1976-01-01

    The moderating effect of sex-role attitudes in relation to the predictive validity of Mehrabian's achievement tendency scale for females is examined. The scale predicts better for academic achievement with females classified as non-traditional in sex-role orientation, and in social achievement for females classified as traditional. (Author/JKS)

  10. "Standards"-based Mathematics Curricula and Secondary Students' Performance on Standardized Achievement Tests

    ERIC Educational Resources Information Center

    Harwell, Michael R.; Post, Thomas R.; Maeda, Yukiko; Davis, Jon D.; Cutler, Arnold L.; Andersen, Edwin; Kahan, Jeremy A.

    2007-01-01

    The current study examined the mathematical achievement of high school students enrolled for 3 years in one of three NSF funded "Standards"-based curricula (IMP, CMIC, MMOW). The focus was on traditional topics in mathematics as measured by subtests of a standardized achievement test and a criterion-referenced test of mathematics achievement.…

  11. Measuring Emotions in Students' Learning and Performance: The Achievement Emotions Questionnaire (AEQ)

    ERIC Educational Resources Information Center

    Pekrun, Reinhard; Goetz, Thomas; Frenzel, Anne C.; Barchfeld, Petra; Perry, Raymond P.

    2011-01-01

    Aside from test anxiety scales, measurement instruments assessing students' achievement emotions are largely lacking. This article reports on the construction, reliability, internal validity, and external validity of the Achievement Emotions Questionnaire (AEQ) which is designed to assess various achievement emotions experienced by students in…

  12. Preparation of Novel Li4 SiO4 Sorbents with Superior Performance at Low CO2 Concentration.

    PubMed

    Yang, Xinwei; Liu, Wenqiang; Sun, Jian; Hu, Yingchao; Wang, Wenyu; Chen, Hongqiang; Zhang, Yang; Li, Xian; Xu, Minghou

    2016-07-01

    This work produced Li4 SiO4 sorbents through an impregnated-suspension method to overcome its typical poor performance at low CO2 concentrations. A SiO2 colloidal solution and two different organic lithium precursors were selected. A bulgy surface morphology (and thus, the significantly enlarged reacting surface area) was obtained for Li4 SiO4 , which contributed to the high absorption capacity. As a result, the capacity in cyclic tests at 15 vol % CO2 was approximately 8 times higher than conventional Li4 SiO4 prepared through a solid-state reaction. The phenomenon of a progressively increasing capacity (i.e., sustainable usage) was observed over the 40 cycles investigated, and this increasing trend continued to the last cycle. Correspondingly, over the course of the multicycle absorption/ desorption processes, the sorbents evolve from lacking porosity to having a high number of micron-sized pores. PMID:27312486

  13. Superior performance of liposomes over enzymatic amplification in a high-throughput assay for myoglobin in human serum.

    PubMed

    Edwards, Katie A; Meyers, Katherine J; Leonard, Barbara; Baeumner, Antje J

    2013-05-01

    Myoglobin is one of several cardiac markers which become elevated in the blood following an acute myocardial infarction and can aid in the diagnosis of a heart attack. Here, a sandwich immunoassay for myoglobin was developed, including a thorough optimization of fluorescent dye-encapsulating liposomes versus enzymatic amplification (alkaline phosphatase and horseradish peroxidase) at each step. The optimized microtiter plate-based assay was capable of detecting as low as 11.3 pg/mL myoglobin and was successfully applied for the quantification of myoglobin in human serum. In comparison to enzymatic approaches, the liposomes demonstrated lower limits of detection, significantly reduced limits of quantification, improved signal discrimination through substantial signal enhancement, and reduced assay time. Liposomes were stable and functional at ambient temperatures for over 400 days. Finally, ease of use was greater due to lack of reliance on additional reagents, non-time-based signal enhancement, and excellent photostability. Optimal conditions identified for enzymatic approaches can also be used for liposome amplification, which makes substitution of these liposomes into existing assays straightforward. Thus, the extensive studies carried out here suggest that liposomes may be incorporated into formats currently utilizing enzymatic enhanced fluorescence with a potential for increased performance on various levels.

  14. Coaxial electrospinning of WO3 nanotubes functionalized with bio-inspired Pd catalysts and their superior hydrogen sensing performance

    NASA Astrophysics Data System (ADS)

    Choi, Seon-Jin; Chattopadhyay, Saptarshi; Kim, Jae Jin; Kim, Sang-Joon; Tuller, Harry L.; Rutledge, Gregory C.; Kim, Il-Doo

    2016-04-01

    Macroporous WO3 nanotubes (NTs) functionalized with nanoscale catalysts were fabricated using coaxial electrospinning combined with sacrificial templating and protein-encapsulated catalysts. The macroporous thin-walled nanotubular structures were obtained by introducing colloidal polystyrene (PS) particles to a shell solution of W precursor and poly(vinylpyrrolidone). After coaxial electrospinning with a core liquid of mineral oil and subsequent calcination, open pores with an average diameter of 173 nm were formed on the surface of WO3 NTs due to decomposition of the PS colloids. In addition, catalytic Pd nanoparticles (NPs) were synthesized using bio-inspired protein cages, i.e., apoferritin, and uniformly dispersed within the shell solution and subsequently on the WO3 NTs. The resulting Pd functionalized macroporous WO3 NTs were demonstrated to be high performance hydrogen (H2) sensors. In particular, Pd-functionalized macroporous WO3 NTs exhibited a very high H2 response (Rair/Rgas) of 17.6 at 500 ppm with a short response time. Furthermore, the NTs were shown to be highly selective for H2 compared to other gases such as carbon monoxide (CO), ammonia (NH3), and methane (CH4). The results demonstrate a new synthetic method to prepare highly porous nanotubular structures with well-dispersed nanoscale catalysts, which can provide improved microstructures for chemical sensing.Macroporous WO3 nanotubes (NTs) functionalized with nanoscale catalysts were fabricated using coaxial electrospinning combined with sacrificial templating and protein-encapsulated catalysts. The macroporous thin-walled nanotubular structures were obtained by introducing colloidal polystyrene (PS) particles to a shell solution of W precursor and poly(vinylpyrrolidone). After coaxial electrospinning with a core liquid of mineral oil and subsequent calcination, open pores with an average diameter of 173 nm were formed on the surface of WO3 NTs due to decomposition of the PS colloids. In addition

  15. Monitoring the performance of community forestry to achieve REDD+ goals through geospatial methods

    NASA Astrophysics Data System (ADS)

    Gilani, H.; Krishna Gautam, S.; Murthy, M. S. R.; Koju, U. A.; Uddin, K.; Karky, B.

    2014-11-01

    Measurement, reporting and verification (MRV) is included in the Cancun, Mexico, in 2010 under climate change agreements, as one of the most critical elements necessary for the successful implementation of any reducing of emissions from deforestation and forest degradation and the role of conservation, sustainable management of forests and enhancement of forest carbon stocks in developing countries (REDD+) mechanism. Community forestry is recognised as a successful model for conserving forests, raising awareness among local people and decentralising the forest governance practices. In the world, Nepal is considered as a leader in community-based forest management. This study conducted in 16 community forests (2384.76 ha) of Kayar Khola watershed (8002 ha) of Chitwan district, Nepal. In this paper, satellite images IKONOS-2 (2002) and GeoEye-1 (2009 & 2012) were used which have 1 m and 0.5 m ground spatial distance (GSD) respectively. Geographic information system (GIS) participatory approach was embraced for the boundaries delineation of community forests. Geographic object-based image analysis (GEOBIA) classification technique was performed and overall accuracy 94 % with 92.91 % producer's and 96.2 % user's accuracies. Through change matrix method, 25.49 ha and 1.08 ha area deforested while 179.84 ha and 33.24 ha reforested in two time periods 2002-2009 and 2009-2012 respectively. Overall within 16 community forests, "Close broadleaved to Open broadleaved" 4.42 ha and 4 ha area is transferred between 2002-2009 and 2009-2012 respectively. While "Open broadleaved to Close broadleaved" 29.25 ha and 31.1 ha area is converted in seven years (2002-2009) and in three years (2009-2012) respectively. Coefficient of determination (R2) 0.833 achieved through a line-intercept transect between number of segmented and observed tree crowns. Maximum numbers of the counted trees exist below 20 m2, which show the forest of the study area is not mature and has capacity to

  16. On the Value of Intrinsic Rather than Traditional Achievement Goals for Performing Artists: A Short-Term Prospective Study

    ERIC Educational Resources Information Center

    Lacaille, Natalie; Koestner, Richard; Gaudreau, Patrick

    2007-01-01

    Educational researchers have examined the effect of achievement goals on student performance, and suggest that both mastery goals and performance-approach goals are beneficial, whereas performance-avoidance goals are harmful. Recent research proposes that these results may not be generalized in the domain of music. The purpose of the present study…

  17. Measuring Metacognition and Reaction Time: Further Findings on the Performances of General Education, Low-Achieving, and Institutionally Raised Students

    ERIC Educational Resources Information Center

    Al-Hilawani, Yasser A.; Abdullah, Ahmad A.

    2010-01-01

    The purpose of this study was to use the picture format to examine in depth the metacognitive performances and reaction time in general education, low-achieving, and institutionally raised students. Results revealed that institutionally raised students, unlike low-achieving students, took significantly the longest reaction time to finish the test…

  18. The relationship between medical students’ epistemological beliefs and achievement on a clinical performance examination

    PubMed Central

    Oh, Sun-A; Chung, Eun-Kyung; Han, Eui-Ryoung; Woo, Young-Jong; Kevin, Deiter

    2016-01-01

    Purpose: This study was to explore the relationship between clinical performance examination (CPX) achievement and epistemological beliefs to investigate the potentials of epistemological beliefs in ill-structured medical problem solving tasks. Methods: We administered the epistemological beliefs questionnaire (EBQ) to fourth-year medical students and correlated the results with their CPX scores. The EBQ comprised 61 items reflecting five belief systems: certainty of knowledge, source of knowledge, rigidity of learning, ability to learn, and speed of knowledge acquisition. The CPX included scores for history taking, physical examination, and patient-physician interaction. Results: The higher epistemological beliefs group obtained significantly higher scores on the CPX with regard to history taking and patient-physician interaction. The epistemological beliefs scores on certainty of knowledge and source of knowledge were significantly positively correlated with patient-physician interaction. The epistemological beliefs scores for ability to learn were significantly positively correlated with those for history taking, physical examination, and patient-physician interaction. Conclusion: Students with more sophisticated and advanced epistemological beliefs stances used more comprehensive and varied approaches in the patient-physician interaction. Therefore, educational efforts that encourage discussions pertaining to epistemological views should be considered to improve clinical reasoning and problem-solving competence in the clinic setting. PMID:26838566

  19. A hydrological modeling framework for defining achievable performance standards for pesticides.

    PubMed

    Rousseau, Alain N; Lafrance, Pierre; Lavigne, Martin-Pierre; Savary, Stéphane; Konan, Brou; Quilbé, Renaud; Jiapizian, Paul; Amrani, Mohamed

    2012-01-01

    This paper proposes a hydrological modeling framework to define achievable performance standards (APSs) for pesticides that could be attained after implementation of recommended management actions, agricultural practices, and available technologies (i.e., beneficial management practices [BMPs]). An integrated hydrological modeling system, Gestion Intégrée des Bassins versants à l'aide d'un Système Informatisé, was used to quantify APSs for six Canadian watersheds for eight pesticides: atrazine, carbofuran, dicamba, glyphosate, MCPB, MCPA, metolachlor, and 2,4-D. Outputs from simulation runs to predict pesticide concentration under current conditions and in response to implementation of two types of beneficial management practices (reduced pesticide application rate and 1- to 10-m-wide edge-of-field and/or riparian buffer strips, implemented singly or in combination) showed that APS values for scenarios with BMPs were less than those for current conditions. Moreover, APS values at the outlet of watersheds were usually less than ecological thresholds of good condition, when available. Upstream river reaches were at greater risk of having concentrations above a given ecological thresholds because of limited stream flows and overland loads of pesticides. Our integrated approach of "hydrological modeling-APS estimation-ecotoxicological significance" provides the most effective interpretation possible, for management and education purposes, of the potential biological impact of predicted pesticide concentrations in rivers.

  20. The effects of training and competition on achievement goals, motivational responses, and performance in a golf-putting task.

    PubMed

    van de Pol P, K C; Kavussanu, Maria; Ring, Christopher

    2012-12-01

    This study examined whether (a) training and competition influence achievement goals, effort, enjoyment, tension, and performance; (b) achievement goals mediate the effects of training and competition on effort, enjoyment, tension, and performance; and (c) the context influences the relationships between goals and effort, enjoyment, tension, and performance. Participants (32 males, 28 females; M age = 19.12 years) performed a golf-putting task in a training condition and a competition condition and completed measures of goal involvement, effort, enjoyment, and tension; putting performance was also measured. Both task and ego involvement varied across training and competition, and variation in ego involvement explained variation in effort and enjoyment between these conditions. Ego involvement positively predicted effort in training and performance in competition, and interacted positively with task involvement to predict effort and enjoyment in competition. Our findings suggest that the distinction between training and competition is a valuable one when examining individuals' achievement motivation. PMID:23204359

  1. The CryoSat Interferometer after 6 years in orbit: calibration and achievable performance

    NASA Astrophysics Data System (ADS)

    Scagliola, Michele; Fornari, Marco; De Bartolomei, Maurizio; Bouffard, Jerome; Parrinello, Tommaso

    2016-04-01

    The main payload of CryoSat is a Ku-band pulse width limited radar altimeter, called SIRAL (Synthetic interferometric radar altimeter). When commanded in SARIn (synthetic aperture radar interferometry) mode, through coherent along-track processing of the returns received from two antennas, the interferometric phase related to the first arrival of the echo is used to retrieve the angle of arrival of the scattering in the across-track direction. In fact, the across-track echo direction can be derived by exploiting the precise knowledge of the baseline vector (i.e. the vector between the two antennas centers of phase) and simple geometry. The end-to-end calibration strategy for the CryoSat interferometer consists on in-orbit calibration campaigns following the approach described in [1]. From the beginning of the CryoSat mission, about once a year the interferometer calibration campaigns have been periodically performed by rolling left and right the spacecraft of about ±0.4 deg. This abstract is aimed at presenting our analysis of the calibration parameters and of the achievable performance of the CryoSat interferometer over the 6 years of mission. Additionally, some further studies have been performed to assess the accuracy of the roll angle computed on ground as function of the aberration (the apparent displacement of a celestial object from its true position, caused by the relative motion of the observer and the object) correction applied to the attitude quaternions, provided by the Star Tracker mounted on-board. In fact, being the roll information crucial to obtain an accurate estimate of the angle of arrival, the data from interferometer calibration campaigns have been used to verify how the application of the aberration correction affects the roll information and, in turns, the measured angle of arrival. [1] Galin, N.; Wingham, D.J.; Cullen, R.; Fornari, M.; Smith, W.H.F.; Abdalla, S., "Calibration of the CryoSat-2 Interferometer and Measurement of Across

  2. Superior cycle performance and high reversible capacity of SnO2/graphene composite as an anode material for lithium-ion batteries

    PubMed Central

    Liu, Lilai; An, Maozhong; Yang, Peixia; Zhang, Jinqiu

    2015-01-01

    SnO2/graphene composite with superior cycle performance and high reversible capacity was prepared by a one-step microwave-hydrothermal method using a microwave reaction system. The SnO2/graphene composite was characterized by X-ray diffraction, thermogravimetric analysis, Fourier-transform infrared spectroscopy, Raman spectroscopy, scanning electron microscope, X-ray photoelectron spectroscopy, transmission electron microscopy and high resolution transmission electron microscopy. The size of SnO2 grains deposited on graphene sheets is less than 3.5 nm. The SnO2/graphene composite exhibits high capacity and excellent electrochemical performance in lithium-ion batteries. The first discharge and charge capacities at a current density of 100 mA g−1 are 2213 and 1402 mA h g−1 with coulomb efficiencies of 63.35%. The discharge specific capacities remains 1359, 1228, 1090 and 1005 mA h g−1 after 100 cycles at current densities of 100, 300, 500 and 700 mA g−1, respectively. Even at a high current density of 1000 mA g−1, the first discharge and charge capacities are 1502 and 876 mA h g−1, and the discharge specific capacities remains 1057 and 677 mA h g−1 after 420 and 1000 cycles, respectively. The SnO2/graphene composite demonstrates a stable cycle performance and high reversible capacity for lithium storage. PMID:25761938

  3. Superior cycle performance and high reversible capacity of SnO2/graphene composite as an anode material for lithium-ion batteries

    NASA Astrophysics Data System (ADS)

    Liu, Lilai; An, Maozhong; Yang, Peixia; Zhang, Jinqiu

    2015-03-01

    SnO2/graphene composite with superior cycle performance and high reversible capacity was prepared by a one-step microwave-hydrothermal method using a microwave reaction system. The SnO2/graphene composite was characterized by X-ray diffraction, thermogravimetric analysis, Fourier-transform infrared spectroscopy, Raman spectroscopy, scanning electron microscope, X-ray photoelectron spectroscopy, transmission electron microscopy and high resolution transmission electron microscopy. The size of SnO2 grains deposited on graphene sheets is less than 3.5 nm. The SnO2/graphene composite exhibits high capacity and excellent electrochemical performance in lithium-ion batteries. The first discharge and charge capacities at a current density of 100 mA g-1 are 2213 and 1402 mA h g-1 with coulomb efficiencies of 63.35%. The discharge specific capacities remains 1359, 1228, 1090 and 1005 mA h g-1 after 100 cycles at current densities of 100, 300, 500 and 700 mA g-1, respectively. Even at a high current density of 1000 mA g-1, the first discharge and charge capacities are 1502 and 876 mA h g-1, and the discharge specific capacities remains 1057 and 677 mA h g-1 after 420 and 1000 cycles, respectively. The SnO2/graphene composite demonstrates a stable cycle performance and high reversible capacity for lithium storage.

  4. One-dimensional porous nanofibers of Co3O4 on the carbon matrix from human hair with superior lithium ion storage performance

    NASA Astrophysics Data System (ADS)

    Tan, Yanli; Gao, Qiuming; Yang, Chunxiao; Yang, Kai; Tian, Weiqian; Zhu, Lihua

    2015-07-01

    One-dimensional (1D) hierarchical porous nanofibers of Co3O4 possessing of (220) facets on the carbon matrix from human hair (H2@Co3O4) with 20-30 nm in width and 3-5 μm in length are prepared by a facile solvothermal and calcination approach. The well crystallized small Co3O4 particles with the diameter of about 8-12 nm were closely aggregated together in the nanofibers. Electrochemical analyses show that the first discharge capacity of H2@Co3O4 electrode is 1368 mAh g-1 at the current density of 0.1 A g-1 based on the total mass of composite. A high reversible capacity of 916 mAh g -1 was obtained over 100 cycles at 0.1 A g-1, presenting a good cycling stability. When cycled at a high current density of 1 and 2 A g-1, the specific capacity of 659 and 573 mAh g-1 could be still achieved, respectively, indicating a superior power capability.

  5. One-dimensional porous nanofibers of Co3O4 on the carbon matrix from human hair with superior lithium ion storage performance

    PubMed Central

    Tan, Yanli; Gao, Qiuming; Yang, Chunxiao; Yang, Kai; Tian, Weiqian; Zhu, Lihua

    2015-01-01

    One-dimensional (1D) hierarchical porous nanofibers of Co3O4 possessing of (220) facets on the carbon matrix from human hair (H2@Co3O4) with 20–30 nm in width and 3–5 μm in length are prepared by a facile solvothermal and calcination approach. The well crystallized small Co3O4 particles with the diameter of about 8–12 nm were closely aggregated together in the nanofibers. Electrochemical analyses show that the first discharge capacity of H2@Co3O4 electrode is 1368 mAh g−1 at the current density of 0.1 A g−1 based on the total mass of composite. A high reversible capacity of 916 mAh g −1 was obtained over 100 cycles at 0.1 A g−1, presenting a good cycling stability. When cycled at a high current density of 1 and 2 A g−1, the specific capacity of 659 and 573 mAh g−1 could be still achieved, respectively, indicating a superior power capability. PMID:26201874

  6. Achievement First: Developing a Teacher Performance Management System That Recognizes Excellence

    ERIC Educational Resources Information Center

    Curtis, Rachel

    2011-01-01

    Teachers are the single most important school-related factor in students' learning, and improving student learning is the single most important goal at Achievement First (AF), a fast-growing public charter school network in the Northeast. To achieve this goal, the AF team has worked to establish a common understanding of effective instructional…

  7. To Master or Perform? Exploring Relations between Achievement Goals and Conceptual Change Learning

    ERIC Educational Resources Information Center

    Ranellucci, John; Muis, Krista R.; Duffy, Melissa; Wang, Xihui; Sampasivam, Lavanya; Franco, Gina M.

    2013-01-01

    Background: Research is needed to explore conceptual change in relation to achievement goal orientations and depth of processing. Aims: To address this need, we examined relations between achievement goals, use of deep versus shallow processing strategies, and conceptual change learning using a think-aloud protocol. Sample and Method:…

  8. How Do Relationships Influence Student Achievement? Understanding Student Performance from a General, Social Psychological Standpoint

    ERIC Educational Resources Information Center

    Aspelin, Jonas

    2012-01-01

    This article explores the influence of relationships on student achievement by examining empirical evidence and by adopting a social psychological theory. Initially, the issue is addressed from a national, Swedish context. Thereafter, two general questions are raised: (1) What is the influence of relationships on student achievement, according to…

  9. Performance-Based Music Ensembles' Effects on Academic Achievement: A Correlational Study

    ERIC Educational Resources Information Center

    Stevenson, Timothy Francis

    2013-01-01

    As increasing student achievement levels for all learners continues to drive the focus of education, identifying strategies and opportunities to accomplish this goal becomes progressively more important. This study explored the concepts of self-efficacy, self-efficacy for self-regulated learning, and self-efficacy for academic achievement in…

  10. Relationships of cognitive and metacognitive learning strategies to mathematics achievement in four high-performing East Asian education systems.

    PubMed

    Areepattamannil, Shaljan; Caleon, Imelda S

    2013-01-01

    The authors examined the relationships of cognitive (i.e., memorization and elaboration) and metacognitive learning strategies (i.e., control strategies) to mathematics achievement among 15-year-old students in 4 high-performing East Asian education systems: Shanghai-China, Hong Kong-China, Korea, and Singapore. In all 4 East Asian education systems, memorization strategies were negatively associated with mathematics achievement, whereas control strategies were positively associated with mathematics achievement. However, the association between elaboration strategies and mathematics achievement was a mixed bag. In Shanghai-China and Korea, elaboration strategies were not associated with mathematics achievement. In Hong Kong-China and Singapore, on the other hand, elaboration strategies were negatively associated with mathematics achievement. Implications of these findings are briefly discussed.

  11. Achievable Performance and Effective Interrogator Design for SAW RFID Sensor Tags

    NASA Technical Reports Server (NTRS)

    Barton, Richard J.

    2011-01-01

    For many NASA missions, remote sensing is a critical application that supports activities such as environmental monitoring, planetary science, structural shape and health monitoring, non-destructive evaluation, etc. The utility of the remote sensing devices themselves is greatly increased if they are passive that is, they do not require any on-board power supply such as batteries and if they can be identified uniquely during the sensor interrogation process. Additional passive sensor characteristics that enable greater utilization in space applications are small size and weight, long read ranges with low interrogator power, ruggedness, and operability in extreme environments (vacuum, extreme high/low temperature, high radiation, etc.) In this paper, we consider one very promising passive sensor technology, called surface acoustic wave (SAW) radio-frequency identification (RFID), that satisfies all of these criteria. Although SAW RFID tags have great potential for use in numerous space-based remote sensing applications, the limited collision resolution capability of current generation tags limits the performance in a cluttered sensing environment. That is, as more SAW-based sensors are added to the environment, numerous tag responses are superimposed at the receiver and decoding all or even a subset of the telemetry becomes increasingly difficult. Background clutter generated by reflectors other than the sensors themselves is also a problem, as is multipath interference and signal distortion, but the limiting factor in many remote sensing applications can be expected to be tag mutual interference. This problem may be greatly mitigated by proper design of the SAW tag waveform, but that remains an open research problem, and in the meantime, several other related questions remain to be answered including: What are the fundamental relationships between tag parameters such as bit-rate, time-bandwidth-product, SNR, and achievable collision resolution? What are the

  12. N-doped graphene layers encapsulated NiFe alloy nanoparticles derived from MOFs with superior electrochemical performance for oxygen evolution reaction

    NASA Astrophysics Data System (ADS)

    Feng, Yi; Yu, Xin-Yao; Paik, Ungyu

    2016-09-01

    Water splitting, an efficient approach for hydrogen production, is often hindered by unfavorable kinetics of oxygen evolution reaction (OER). In order to reduce the overpotential, noble metal oxides-based electrocatalysts like RuO2 and IrO2 are usually utilized. However, due to their scarcity, the development of cost-effective non-precious OER electrocatalysts with high efficiency and good stability is urgently required. Herein, we report a facile one-step annealing of metal-organic frameworks (MOFs) strategy to synthesize N-doped graphene layers encapsulated NiFe alloy nanoparticles (NiFe@C). Through tuning the nanoparticle size and calcination temperature, NiFe@C with an average size of around 16 nm obtained at 700 °C exhibits superior OER performance with an overpotential of only 281 mV at 10 mA cm‑2 and high durability. The facile synthesis method and excellent electrochemical performance show great potential of NiFe@C in replacing the precious metal-based electrocatalysts in the OER.

  13. N-doped graphene layers encapsulated NiFe alloy nanoparticles derived from MOFs with superior electrochemical performance for oxygen evolution reaction

    PubMed Central

    Feng, Yi; Yu, Xin-Yao; Paik, Ungyu

    2016-01-01

    Water splitting, an efficient approach for hydrogen production, is often hindered by unfavorable kinetics of oxygen evolution reaction (OER). In order to reduce the overpotential, noble metal oxides-based electrocatalysts like RuO2 and IrO2 are usually utilized. However, due to their scarcity, the development of cost-effective non-precious OER electrocatalysts with high efficiency and good stability is urgently required. Herein, we report a facile one-step annealing of metal-organic frameworks (MOFs) strategy to synthesize N-doped graphene layers encapsulated NiFe alloy nanoparticles (NiFe@C). Through tuning the nanoparticle size and calcination temperature, NiFe@C with an average size of around 16 nm obtained at 700 °C exhibits superior OER performance with an overpotential of only 281 mV at 10 mA cm−2 and high durability. The facile synthesis method and excellent electrochemical performance show great potential of NiFe@C in replacing the precious metal-based electrocatalysts in the OER. PMID:27658968

  14. One-step solvothermal deposition of ZnO nanorod arrays on a wood surface for robust superamphiphobic performance and superior ultraviolet resistance

    PubMed Central

    Yao, Qiufang; Wang, Chao; Fan, Bitao; Wang, Hanwei; Sun, Qingfeng; Jin, Chunde; Zhang, Hong

    2016-01-01

    In the present paper, uniformly large-scale wurtzite-structured ZnO nanorod arrays (ZNAs) were deposited onto a wood surface through a one-step solvothermal method. The as-prepared samples were characterized by X-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), thermogravimetry (TG), and differential thermal analysis (DTA). ZNAs with a diameter of approximately 85 nm and a length of approximately 1.5 μm were chemically bonded onto the wood surface through hydrogen bonds. The superamphiphobic performance and ultraviolet resistance were measured and evaluated by water or oil contact angles (WCA or OCA) and roll-off angles, sand abrasion tests and an artificially accelerated ageing test. The results show that the ZNA-treated wood demonstrates a robust superamphiphobic performance under mechanical impact, corrosive liquids, intermittent and transpositional temperatures, and water spray. Additionally, the as-prepared wood sample shows superior ultraviolet resistance. PMID:27775091

  15. The Relationship Between Achievement and Laboratory Skills to the Number of Experiments Performed by the High School Chemistry Student.

    ERIC Educational Resources Information Center

    Grosmark, Jay Waldo

    The purpose of this study was to determine the effectiveness of doubling the laboratory experiments and time in the laboratory on student achievement, performance on laboratory skills, and attitude toward high school chemistry. One hundred forty-three students were assigned either of two treatments. All students performed the same basic…

  16. The Influence of the Antecedent Variable on the Teachers' Performance through Achievement Motivation in Senior High School

    ERIC Educational Resources Information Center

    Dewi, Erni R.; Bundu, Patta; Tahmir, Suradi

    2016-01-01

    This study aims at analysing whether the antecedent variable directly affects the performance of the high school teachers or not. In addition, this research strives to find out whether the antecedent variable indirectly affects the teachers' performance through the achievement motivation of the high school teachers. It was a quantitative research…

  17. A Comprehensive Review of the Literature on the Effects of Breakfast on Mental Performance and Scholastic Achievement.

    ERIC Educational Resources Information Center

    Purnell, James P.

    A review of the literature on the effects of breakfast on mental performance and scholastic achievement reveals a dichotomy between the theoretical and the empirical literature. Whereas theoretical considerations maintain that breakfast makes a significant difference in mental performance in the late morning hours, empirical evidence can be…

  18. Using Performance Management To Achieve Quality Program Results. A Technical Assistance Guide. Research Report 89-03.

    ERIC Educational Resources Information Center

    Laventhol & Horwath, Philadelphia, PA.

    This guide provides assistance in using two primary management tools--the performance standards and performance-based, fixed unit price contracts--to achieve satisfactory results in Job Training Partnership Act (JTPA) programs. The guide is organized in six chapters. Chapter 1 reviews the original purpose of the JTPA and introduces the investment…

  19. Achievable Performance and Effective Interrogator Design for SAW RFID Sensor Tags

    NASA Technical Reports Server (NTRS)

    Barton Richard J.

    2012-01-01

    current generation tags limits the performance in a cluttered sensing environment. That is, as more SAW-based sensors are added to the environment, numerous tag responses are superimposed at the receiver and decoding all or even a subset of the telemetry becomes increasingly difficult. Background clutter generated by reflectors other than the sensors themselves is also a problem, as is multipath interference and signal distortion, but the limiting factor in many remote sensing applications can be expected to be tag mutual interference. This problem may be greatly mitigated by proper design of the SAW tag waveform, but that remains an open research problem, and in the meantime, several other related questions remain to be answered including: (1) What are the fundamental relationships between tag parameters such as bit-rate, time-bandwidth-product, SNR, and achievable collision resolution? (2) What are the differences in optimal or near-optimal interrogator designs between noise-limited environments and interference-limited environments? (3) What are the performance characteristics of different interrogator designs in term of parameters such as transmitter power level, range, and number of interfering tags? In this paper, we will present the results of a research effort aimed at providing at least partial answers to all of these questions.

  20. Tailoring copper valence states in CuOδ/γ-Al2O3 catalysts by an in situ technique induced superior catalytic performance for simultaneous elimination of NO and CO.

    PubMed

    Yao, Xiaojiang; Gao, Fei; Cao, Yuan; Tang, Changjin; Deng, Yu; Dong, Lin; Chen, Yi

    2013-09-28

    An in situ technique is employed to tailor the valence states of copper in CuOδ/γ-Al2O3 catalysts with the purpose of inducing superior catalytic performance for simultaneous elimination of NO and CO. The catalyst with zero-valent copper exhibits excellent catalytic performance, which is comparable with the conventional supported noble-metal catalysts. PMID:23925070

  1. Pictorial Superiority Effect

    ERIC Educational Resources Information Center

    Nelson, Douglas L.; And Others

    1976-01-01

    Pictures generally show superior recognition relative to their verbal labels. This experiment was designed to link this pictorial superiority effect to sensory or meaning codes associated with the two types of symbols. (Editor)

  2. The Relationship of Laboratory Performance Ratings, Information Achievement and Pencil-Paper Performance Test Scores in College-Level Electricity.

    ERIC Educational Resources Information Center

    Francis, Charles E.

    In this study, a pencil paper performance test (PPPT) was developed and administered to an experimental group of 46 students and a control group of 48 students to determine: (1) the difference between laboratory performance and the successful completion of a laboratory course in electricity, (2) the relationship between laboratory performance as…

  3. The case of the missing supercomputer performance : achieving optimal performance on the 8, 192 processors of ASCI Q

    SciTech Connect

    Petrini, F.; Kerbyson, D. J.; Pakin, S. D.

    2003-01-01

    In this paper we describe how we improved the effective performance of ASCI Q, the world's second-fastest supercomputer, to meet our expectations. Using an arsenal of performance-analysis techniques including analytical models, custom microbenchmarks, full applications, and simulators, we succeeded in observing a serious-but previously undetectable-performance problem. We identified the source of the problem, eliminated the problem, and 'closed the loop' by demonstrating improved application performance. We present our methodology and provide insight into performance analysis that is immediately applicable to other large-scale cluster-based supercomputers.

  4. Predicting End-of-Year Achievement Test Performance: A Comparison of Assessment Methods

    ERIC Educational Resources Information Center

    Kettler, Ryan J.; Elliott, Stephen N.; Kurz, Alexander; Zigmond, Naomi; Lemons, Christopher J.; Kloo, Amanda; Shrago, Jacqueline; Beddow, Peter A.; Williams, Leila; Bruen, Charles; Lupp, Lynda; Farmer, Jeanie; Mosiman, Melanie

    2014-01-01

    Motivated by the multiple-measures clause of recent federal policy regarding student eligibility for alternate assessments based on modified academic achievement standards (AA-MASs), this study examined how scores or combinations of scores from a diverse set of assessments predicted students' end-of-year proficiency status on statewide…

  5. The Relationship between Victimization at School and Achievement: The Cusp Catastrophe Model for Reading Performance

    ERIC Educational Resources Information Center

    Sideridis, Georgios D.; Antoniou, Faye; Stamovlasis, Dimitrios; Morgan, Paul L.

    2013-01-01

    We evaluated the relationship between victimization and academic achievement from a nonlinear perspective using a cusp catastrophe model. Participants were 62 students with identified learning disabilities (LD) using statewide criteria in Greece. Students participated in a 2-year cohort-sequential design. Reading assessments involved measures of…

  6. The Relationship Between Teacher Performance Evaluation Scores and Student Achievement: Evidence From Cincinnati

    ERIC Educational Resources Information Center

    Milanowski, Anthony

    2004-01-01

    In this article, I present the results of an analysis of the relationship between teacher evaluation scores and student achievement on district and state tests in reading, mathematics, and science in a large Midwestern U.S. school district. Within a value-added framework, I correlated the difference between predicted and actual student achievement…

  7. Performance Report for Project CLASS (Chinese Language Achievement through Sequential Study) 1997.

    ERIC Educational Resources Information Center

    Hu, Xue-mei

    Project CLASS (Chinese Language Achievement through Sequential Study), a federally-funded program, introduced the study of Chinese language and culture at Queen Ka'ahumanu Elementary School (Hawaii), forming the foundation of an instructional program to be continued through middle and high school, to meet state foreign language standards. It was…

  8. Understanding Student Goal Orientation Tendencies to Predict Student Performance: A 2x2 Achievement Goal Orientation

    ERIC Educational Resources Information Center

    Miller, Mark Alan

    2013-01-01

    The study tested the 2X2 model of the Achievement Goal Orientation (AGO) theory in a military technical training environment while using the Air Force Officers Qualifying Test's academic aptitude score to control for the differences in the students' academic aptitude. The study method was quantitative and the design was correlational.…

  9. Quality After-School Programming and Its Relationship to Achievement-Related Behaviors and Academic Performance

    ERIC Educational Resources Information Center

    Grassi, Annemarie M.

    2012-01-01

    The purpose of this study is to understand the relationship between quality social support networks developed through high quality afterschool programming and achievement amongst middle school and high school aged youth. This study seeks to develop a deeper understanding of how quality after-school programs influence a youth's developmental…

  10. Improving Low Achievers' Academic Performance at University by Changing the Social Value of Mastery Goals

    ERIC Educational Resources Information Center

    Dompnier, Benoît; Darnon, Céline; Meier, Emanuele; Brandner, Catherine; Smeding, Annique; Butera, Fabrizio

    2015-01-01

    Recent research has shown that, in a university context, mastery goals are highly valued and that students may endorse these goals either because they believe in their utility (i.e., social utility), in which case mastery goals are positively linked to achievement, or to create a positive image of themselves (i.e., social desirability), in which…

  11. Performance Report for Project CLASS (Chinese Language Achievement through Sequential Study), 1998.

    ERIC Educational Resources Information Center

    Hu, Xue-mei

    Project CLASS (Chinese Language Achievement through Sequential Study), a federally-funded program, introduced the study of Chinese language and culture at Queen Ka'ahumanu Elementary School (Hawaii), forming the foundation of an instructional program to be continued through middle and high school, to meet state foreign language standards. In its…

  12. "Standards"-Based Mathematics Curricula and Middle-Grades Students' Performance on Standardized Achievement Tests

    ERIC Educational Resources Information Center

    Post, Thomas R.; Harwell, Michael R.; Davis, Jon D.; Maeda, Yukiko; Cutler, Arnie; Andersen, Edwin; Kahan, Jeremy A.; Norman, Ke Wu

    2008-01-01

    This study examined achievement patterns of middle school students enrolled in Standards-based curricula, in particular those curricula that were funded from a solicitation of proposals through the National Science Foundation (NSF) in the early 1990s (NSF RFP 91-100). Approximately 1400 middle-grades students who had used either the Connected…

  13. Associations between Achievement Goal Orientations and Academic Performance Among Students at a UK Pharmacy School

    PubMed Central

    Hanna, Lezley-Anne; Hanna, Alan; Hall, Karen

    2015-01-01

    Objective. To ascertain goal orientations of pharmacy students and establish whether associations exist between academic performance, gender, or year of study. Methods. Goal orientations were assessed using a validated questionnaire. Respondents were categorized as high or low performers based on university grades. Associations and statistical significance were ascertained using parametric and nonparametric tests and linear regression, as appropriate. Results. A response rate of 60.7% was obtained. High performers were more likely to be female than male. The highest mean score was for mastery approach; the lowest for work avoidance. The mean score for work avoidance was significantly greater for low performers than for high performers and for males than for females. First-year students were most likely to have top scores in mastery and performance approaches. Conclusion. It is encouraging that the highest mean score was for mastery approach orientation, as goal orientation may play a role in academic performance of pharmacy students. PMID:26396273

  14. Nursing to achieve organizational performance: Consider the role of nursing intellectual capital.

    PubMed

    Harris, Alexandra

    2016-05-01

    The success and performance of healthcare organizations relies on the strategic management of knowledge. Nursing Intellectual Capital (NIC) has emerged as a concept involving nursing knowledge resources that create value in healthcare organizations. This article aims to discuss the importance of considering knowledge resources in the context of healthcare performance, with specific reference to NIC. Reflections are then provided on how leaders can look to advance NIC for improved performance. PMID:27060807

  15. The Effect of Performance Pay in Little Rock, Arkansas on Student Achievement. Research Brief

    ERIC Educational Resources Information Center

    Winters, Marcus; Greene, Jay; Ritter, Gary; Marsh, Ryan

    2008-01-01

    This paper examines evidence from a performance-pay program implemented in five Little Rock, Arkansas elementary schools between 2004 and 2007. Using a differences-in-differences approach, the evidence shows that students whose teachers were eligible for performance pay made substantially larger test score gains in math, reading, and language than…

  16. Predicting arithmetical achievement from neuro-psychological performance: a longitudinal study.

    PubMed

    Fayol, M; Barrouillet, P; Marinthe, C

    1998-08-01

    In this article, we show that the performances of 5- to 6-year-old children in arithmetic tests can be predicted from their performances in neuro-psychological tests administered a number of months in advance, independently of their level of development. PMID:9818514

  17. Achievement Investment Prowess: Identifying Cost Efficient Higher Performing Maine Public Schools

    ERIC Educational Resources Information Center

    Batista, Ida A.

    2006-01-01

    Throughout the United States the debate has been frequent, intense, and at times adversarial over how to fund education adequately. Maine has been trying to identify higher performing schools in the hope that practices that contribute to success at higher performing schools can be adapted at similar schools throughout the state. The 1997…

  18. Task Goal Attributes, n Achievement, and Supervisory Performance. Technical Report No. 30.

    ERIC Educational Resources Information Center

    Steers, Richard M.

    A review of the research literature on goal-setting in organizational settings reveals that goal-setting on an individual job results in better task performance. However, the processes behind their effectiveness is unclear. For example, how are various job attributes of task goals related to performance, and how do various individual differences…

  19. Patterns and predictors of adolescent academic achievement and performance in a sample of children with attention-deficit/hyperactivity disorder.

    PubMed

    Langberg, Joshua M; Molina, Brooke S G; Arnold, L Eugene; Epstein, Jeffery N; Altaye, Mekibib; Hinshaw, Stephen P; Swanson, James M; Wigal, Timothy; Hechtman, Lily

    2011-01-01

    The current study examined predictors of academic achievement, measured by standardized test scores, and performance, measured by school grades, in adolescents (Mn age = 16.8) who met diagnostic criteria for Attention-Deficit/Hyperactivity Disorder (ADHD)-Combined type in early childhood (Mn age = 8.5; N = 579). Several mediation models were also tested to determine whether ADHD medication use, receipt of special education services, classroom performance, homework completion, or homework management mediated the relationship between symptoms of ADHD and academic outcomes. Childhood predictors of adolescent achievement differed from those for performance. Classroom performance and homework management mediated the relationship between symptoms of inattention and academic outcomes. PMID:21722025

  20. High-Performance and Omnidirectional Thin-Film Amorphous Silicon Solar Cell Modules Achieved by 3D Geometry Design.

    PubMed

    Yu, Dongliang; Yin, Min; Lu, Linfeng; Zhang, Hanzhong; Chen, Xiaoyuan; Zhu, Xufei; Che, Jianfei; Li, Dongdong

    2015-11-01

    High-performance thin-film hydrogenated amorphous silicon solar cells are achieved by combining macroscale 3D tubular substrates and nanoscaled 3D cone-like antireflective films. The tubular geometry delivers a series of advantages for large-scale deployment of photovoltaics, such as omnidirectional performance, easier encapsulation, decreased wind resistance, and easy integration with a second device inside the glass tube. PMID:26418573

  1. Swine herds achieve high performance by culling low lifetime efficiency sows in early parity.

    PubMed

    Takanashi, Ariko; McTaggart, Iain; Koketsu, Yuzo

    2011-11-01

    Sow lifetime performance and by-parity performance were analyzed using a 3 by 3 factorial design, comprising 3 herd productivity groups and 3 sow efficiency groups. Data was obtained from 101 Japanese herds, totaling 173,526 parity records of 34,929 sows, for the years 2001 to 2006. Sows were categorized into 3 groups based on the lower and upper 25th percentiles of the annualized lifetime pigs born alive: low lifetime efficiency sows (LE sows), intermediate lifetime efficiency sows or high lifetime efficiency sows. Herds were grouped on the basis of the upper and lower 25th percentiles of pigs weaned per mated female per year, averaged over 6 years: high-, intermediate- or low-performing herds. Mixed-effects models were used for comparisons. LE sows in high-performing herds had 57.8 fewer lifetime nonproductive days and 0.5 earlier parity at removal than those in low-performing herds (P<0.05). The number of pigs born alive of LE sows continuously decreased from parity 1 to 5, whereas those of high lifetime efficiency sows gradually increased from parity 1 to 4 before decreasing up to parity ≥ 6 (P<0.05). In conclusion, the LE sows have a performance pattern of decreasing number of pigs born alive across parity. The present study also indicates that high-performing herds culled potential LE sows earlier than the other herds.

  2. Children's Achievement Expectations and Performance as a Function of Two Consecutive Reinforcement Experiences, Sex of Subject, and Sex of Experimenter

    ERIC Educational Resources Information Center

    Montanelli, Dale Soderman; Hill, Kennedy T.

    1969-01-01

    Presents research patterned on two earlier studies by the Crandalls 1963, 1964 on the effects of praise, criticism, and nonreaction on 10-year-old children involved in a marble-dropping task. The subjects tended to increase in performance and decrease in achievement expectancy when criticized. Table, graphs, and bibliography. (RW)

  3. Associative Verbal Encoding (a/v/e): A Measure of Language Performance and Its Relationship to Reading Achievement.

    ERIC Educational Resources Information Center

    Mickelson, Norma I.

    This study examined the assumption that language expression and reading performance are related processes. Subjects included a total of 676 nine-year-old children of heterogeneous socioeconomic status, intelligence, and achievement levels. Verbal fluency was defined as being a measure of associative verbal encoding (a/v/e), wherein children give…

  4. Why IEP Teams Assign Low Performers with Mild Disabilities to the Alternate Assessment Based on Alternate Achievement Standards

    ERIC Educational Resources Information Center

    Cho, Hyun-Jeong; Kingston, Neal

    2013-01-01

    The purpose of this case study was to determine teachers' rationales for assigning students with mild disabilities to alternate assessment based on alternate achievement standards (AA-AAS). In interviews, special educators stated that their primary considerations in making the assignments were low academic performance, student use of extended…

  5. Participation and Performance Reporting for the Alternate Assessment Based on Modified Achievement Standards (AA-MAS). Technical Report 58

    ERIC Educational Resources Information Center

    Albus, Deb; Thurlow, Martha L.; Lazarus, Sheryl S.

    2011-01-01

    This report examines publicly reported participation and performance data for the alternate assessment based on modified achievement standards (AA-MAS). The authors' analysis of these data included all states publicly reporting AA-MAS data, regardless of whether they had received approval to use the results for Title I accountability calculations.…

  6. The Relationship between Students' Reading Performance on Diagnostic Assessments and the Third Grade Reading Achievement Test in Ohio

    ERIC Educational Resources Information Center

    Hollinger, Jamie L.

    2009-01-01

    The purpose of this correlational study was twofold: to examine the relationship of students' reading performance on six different diagnostic reading assessments and the third grade Ohio Reading Achievement Test; and to assist educators in choosing the diagnostic assessments that best identify students at risk of failing the third grade Ohio…

  7. Relationships of Cognitive and Metacognitive Learning Strategies to Mathematics Achievement in Four High-Performing East Asian Education Systems

    ERIC Educational Resources Information Center

    Areepattamannil, Shaljan; Caleon, Imelda S.

    2013-01-01

    The authors examined the relationships of cognitive (i.e., memorization and elaboration) and metacognitive learning strategies (i.e., control strategies) to mathematics achievement among 15-year-old students in 4 high-performing East Asian education systems: Shanghai-China, Hong Kong-China, Korea, and Singapore. In all 4 East Asian education…

  8. Instructional Resources as Determinants of English Language Performance of Secondary School High-Achieving Students in Ibadan, Oyo State

    ERIC Educational Resources Information Center

    Adelodun, Gboyega Adelowo; Asiru, Abdulahi Babatunde

    2015-01-01

    This study examined the role played by instructional resources in enhancing performance of students, especially that of high-achievers, in English Language. The study is descriptive in nature and it adopted a survey design. Simple random sampling technique was used for the selection of fifty (50) SSI-SSIII students from five schools in Ibadan…

  9. Conscientiousness, Achievement Striving, and Intelligence as Performance Predictors in a Sample of German Psychology Students: Always a Linear Relationship?

    ERIC Educational Resources Information Center

    Ziegler, Matthias; Knogler, Maximilian; Buhner, Markus

    2009-01-01

    Studies on the interface between cognitive ability (intelligence) and personality in the prediction of academic performance have yielded mixed results so far. Especially an interaction between conscientiousness (and its facet achievement striving) and intelligence has been investigated. The hypothesis is that conscientiousness enhances the impact…

  10. Pilot Study: EatFit Impacts Sixth Graders' Academic Performance on Achievement of Mathematics and English Education Standards

    ERIC Educational Resources Information Center

    Shilts, Mical Kay; Lamp, Cathi; Horowitz, Marcel; Townsend, Marilyn S.

    2009-01-01

    Objective: Investigate the impact of a nutrition education program on student academic performance as measured by achievement of education standards. Design: Quasi-experimental crossover-controlled study. Setting: California Central Valley suburban elementary school (58% qualified for free or reduced-priced lunch). Participants: All sixth-grade…

  11. The Black-White-Other Achievement Gap: Testing Theories of Academic Performance among Multiracial and Monoracial Adolescents

    ERIC Educational Resources Information Center

    Herman, Melissa R.

    2009-01-01

    The study presented here tested three theories of racial differences in academic performance among monoracial and multiracial high school students. These theories (status attainment, oppositional culture, and educational attitudes) were developed to explain differences in achievement among monoracial groups, but the study tested how the theories…

  12. A University Engagement Model for Achieving Technology Adoption and Performance Improvement Impacts in Healthcare, Manufacturing, and Government

    ERIC Educational Resources Information Center

    McKinnis, David R.; Sloan, Mary Anne; Snow, L. David; Garimella, Suresh V.

    2014-01-01

    The Purdue Technical Assistance Program (TAP) offers a model of university engagement and service that is achieving technology adoption and performance improvement impacts in healthcare, manufacturing, government, and other sectors. The TAP model focuses on understanding and meeting the changing and challenging needs of those served, always…

  13. Patterns and Predictors of Adolescent Academic Achievement and Performance in a Sample of Children with Attention-Deficit/Hyperactivity Disorder

    ERIC Educational Resources Information Center

    Langberg, Joshua M.; Molina, Brooke S. G.; Arnold, L. Eugene; Epstein, Jeffery N.; Altaye, Mekibib; Hinshaw, Stephen P.; Swanson, James M.; Wigal, Timothy; Hechtman, Lily

    2011-01-01

    The current study examined predictors of academic achievement, measured by standardized test scores, and performance, measured by school grades, in adolescents (Mn = 16.8) who met diagnostic criteria for Attention-Deficit/Hyperactivity Disorder (ADHD)-Combined type in early childhood (Mn age = 8.5; N = 579). Several mediation models were also…

  14. Prior Mathematics Achievement, Cognitive Appraisals and Anxiety as Predictors of Finnish Students' Later Mathematics Performance and Career Orientation

    ERIC Educational Resources Information Center

    Kyttala, Minna; Bjorn, Piia Maria

    2010-01-01

    The aim of this two-year longitudinal study was to investigate the role and impact of prior mathematics performance, cognitive appraisals and mathematics-specific, affective anxiety in determining later mathematics achievement and future career orientation among Finnish adolescents. The basic ideas of the control-value theory, assumed to be…

  15. Locus of Control and Achievement Motivation as Moderators of the Expectancy-Academic Performance Relationship

    ERIC Educational Resources Information Center

    Batlis, Nick C.; Waters, L. K.

    1973-01-01

    Expectancy theory predictions of course performance were tested for a sample of 195 undergraduates; significant prediction was attained for the total sample using a log linear expectancy model. (Author)

  16. Assessing Medicare's hospital pay-for-performance programs and whether they are achieving their goals.

    PubMed

    Kahn, Charles N; Ault, Thomas; Potetz, Lisa; Walke, Thomas; Chambers, Jayne Hart; Burch, Samantha

    2015-08-01

    Three separate pay-for-performance programs affect the amount of Medicare payment for inpatient services to about 3,400 US hospitals. These payments are based on hospital performance on specified measures of quality of care. A growing share of Medicare hospital payments (6 percent by 2017) are dependent upon how hospitals perform under the Hospital Readmissions Reduction Program, the Value-Based Purchasing Program, and the Hospital-Acquired Condition Reduction Program. In 2015 four of five hospitals subject to these programs will be penalized under one or more of them, and more than one in three major teaching hospitals will be penalized under all three. Interactions among these programs should be considered going forward, including overlap among measures and differences in scoring performance. PMID:26240240

  17. Enhancing the photovoltaic performance and stability of QDSSCs using surface reinforced Pt nanostructures with controllable morphology and superior electrocatalysis via cost-effective chemical bath deposition.

    PubMed

    Rao, S Srinivasa; Durga, Ikkurthi Kanaka; Kang, Tae-Su; Kim, Soo-Kyoung; Punnoose, Dinah; Gopi, Chandu V V M; Eswar Reddy, Araveeti; Krishna, T N V; Kim, Hee-Je

    2016-02-28

    To make quantum-dot sensitized solar cells (QDSSCs) competitive, photovoltaic parameters such as the power conversion efficiency (PCE) and fill factor (FF) must become comparable to those of other emerging solar cell technologies. In the present study, a novel strategy has been successfully developed for a highly efficient surface-modified platinum (Pt) counter electrode (CE) with high catalytic activity and long-term stability in a polysulfide redox electrolyte. The reinforcement of the Pt surface was performed using a thin passivating layer of CuS, NiS, or CoS by simple chemical bath deposition techniques. This method was a more efficient method for reducing the electron recombination in QDSSCs. The optimized Pt/CuS CE shows a very low charge transfer resistance of 37.01 Ω, which is an order of magnitude lower than those of bare Pt (86.32 Ω), Pt/NiS (53.83 Ω), and Pt/CoS (73.51 Ω) CEs. Therefore, the Pt/CuS CEs show much greater catalytic activity in the polysulfide redox electrolyte than Pt, Pt/NiS and Pt/CoS CEs. As a result, under one-sun illumination (AM 1.5G, 100 mW cm(-2)), the Pt/CuS CE exhibits a PCE of 4.32%, which is higher than the values of 1.77%, 2.95%, and 3.25% obtained with bare Pt, Pt/CoS, and Pt/NiS CEs, respectively. The performance of the Pt/CuS CE was enhanced by the improved current density, Cu vacancies with increased S composition, and surface morphology, which enable rapid electron transport and lower the electron recombination rate for the polysulfide electrolyte redox couple. Electrochemical impedance spectroscopy and Tafel polarization revealed that the hybrid CEs reduce interfacial recombination and exhibit better electrochemical and photovoltaic performance compared with a bare Pt CE. The Pt/CuS CE also shows superior stability in the polysulfide electrolyte in a working state for over 10 h, resulting in a long-term electrode stability than Pt CE. PMID:26796086

  18. Enhancing the photovoltaic performance and stability of QDSSCs using surface reinforced Pt nanostructures with controllable morphology and superior electrocatalysis via cost-effective chemical bath deposition.

    PubMed

    Rao, S Srinivasa; Durga, Ikkurthi Kanaka; Kang, Tae-Su; Kim, Soo-Kyoung; Punnoose, Dinah; Gopi, Chandu V V M; Eswar Reddy, Araveeti; Krishna, T N V; Kim, Hee-Je

    2016-02-28

    To make quantum-dot sensitized solar cells (QDSSCs) competitive, photovoltaic parameters such as the power conversion efficiency (PCE) and fill factor (FF) must become comparable to those of other emerging solar cell technologies. In the present study, a novel strategy has been successfully developed for a highly efficient surface-modified platinum (Pt) counter electrode (CE) with high catalytic activity and long-term stability in a polysulfide redox electrolyte. The reinforcement of the Pt surface was performed using a thin passivating layer of CuS, NiS, or CoS by simple chemical bath deposition techniques. This method was a more efficient method for reducing the electron recombination in QDSSCs. The optimized Pt/CuS CE shows a very low charge transfer resistance of 37.01 Ω, which is an order of magnitude lower than those of bare Pt (86.32 Ω), Pt/NiS (53.83 Ω), and Pt/CoS (73.51 Ω) CEs. Therefore, the Pt/CuS CEs show much greater catalytic activity in the polysulfide redox electrolyte than Pt, Pt/NiS and Pt/CoS CEs. As a result, under one-sun illumination (AM 1.5G, 100 mW cm(-2)), the Pt/CuS CE exhibits a PCE of 4.32%, which is higher than the values of 1.77%, 2.95%, and 3.25% obtained with bare Pt, Pt/CoS, and Pt/NiS CEs, respectively. The performance of the Pt/CuS CE was enhanced by the improved current density, Cu vacancies with increased S composition, and surface morphology, which enable rapid electron transport and lower the electron recombination rate for the polysulfide electrolyte redox couple. Electrochemical impedance spectroscopy and Tafel polarization revealed that the hybrid CEs reduce interfacial recombination and exhibit better electrochemical and photovoltaic performance compared with a bare Pt CE. The Pt/CuS CE also shows superior stability in the polysulfide electrolyte in a working state for over 10 h, resulting in a long-term electrode stability than Pt CE.

  19. Well-Combined Magnetically Separable Hybrid Cobalt Ferrite/Nitrogen-Doped Graphene as Efficient Catalyst with Superior Performance for Oxygen Reduction Reaction.

    PubMed

    Lu, Lei; Hao, Qingli; Lei, Wu; Xia, Xifeng; Liu, Peng; Sun, Dongping; Wang, Xin; Yang, Xujie

    2015-11-18

    Catalysts with low-cost, high activity and stability toward oxygen reduction reaction (ORR) are extremely desirable, but its development still remains a great challenge. Here, a novel magnetically separable hybrid of multimetal oxide, cobalt ferrite (CoFe2O4), anchored on nitrogen-doped reduced graphene oxide (CoFe2O4/NG) is prepared via a facile solvothermal method followed by calcination at 500 °C. The structure of CoFe2O4/NG and the interaction of both components are analyzed by several techniques. The possible formation of Co/Fe-N interaction in the CoFe2O4/NG catalyst is found. As a result, the well-combination of CoFe2O4 nanoparticles with NG and its improved crystallinity lead to a synergistic and efficient catalyst with high performance to ORR through a four-electron-transfer process in alkaline medium. The CoFe2O4/NG exhibits particularly comparable catalytic activity as commercial Pt/C catalyst, and superior stability against methanol oxidation and CO poisoning. Meanwhile, it has been proved that both nitrogen doping and the spinel structure of CoFe2O4 can have a significant contribution to the catalytic activity by contrast experiments. Multimetal oxide hybrid demonstrates better catalysis to ORR than a single metal oxide hybrid. All results make the low-cost and magnetically separable CoFe2O4/NG a promising alternative for costly platinum-based ORR catalyst in fuel cells and metal-air batteries. PMID:26390018

  20. Modified surface loading process for achieving improved performance of the quantum dot-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Liu, Feng; Jin, Zhongxiu; Zhu, Jun; Xu, Yafeng; Zhou, Li; Dai, Songyuan

    2016-06-01

    Achieving high surface coverage of the colloidal quantum dots (QDs) on TiO2 films has been challenging for quantum dot-sensitized solar cells (QDSCs). Herein, a general surface engineering approach was proposed to increase the loading of these QDs. It was found that S2- treatment/QD re-uptake process can significantly improve the attachment of the QDs on TiO2 films. Surface concentration of the QDs was improved by ∼60%, which in turn greatly enhances light absorption and decreases carrier recombination in QDSCs. Ensuing QDSCs with optimized QD loading exhibit a power conversion efficiency of 3.66%, 83% higher than those fabricated with standard procedures.

  1. Performance of Students in Project-Based Science Classrooms on a National Measure of Science Achievement.

    ERIC Educational Resources Information Center

    Schneider, Rebecca M.; Krajcik, Joseph; Marx, Ronald W.; Soloway, Elliot

    2002-01-01

    Explores the performance of n=142 high schools students at the 1996 National Assessment of Educational Progress (NAEP) science test who are enrolled in a project based science (PBS) program as compared to a national sample of students. Recommends using inquiry-based approach such as PBS to implement reform in schools. (Contains 32 references.)…

  2. Initial Teacher Education: Does Self-Efficacy Influence Candidate Teacher Academic Achievement and Future Career Performance?

    ERIC Educational Resources Information Center

    Shawer, Saad F.

    2013-01-01

    This quantitative investigation examined the influence of low and high self-efficacy on candidate teacher academic performance in a foreign language teaching methodology course through testing the speculation that high self-efficacy levels would improve pedagogical-content knowledge (PCK). Positivism guided the research design at the levels of…

  3. Effects of Audio- and Videotape Models on Performance Achievement of Beginning Clarinetists.

    ERIC Educational Resources Information Center

    Linklater, Fraser

    1997-01-01

    Investigates the effects on home practice of three different types of cassette tapes (a videotape, a modeling audiotape, and a nonmodeling audiotape) on the performance of beginning clarinet students. Finds no significant impact on amount of weekly practice, of practice using tapes, or of parental help based on tape type. (DSK)

  4. Relationships among Reading Performance, Locus of Control and Achievement for Marginal Admission Students.

    ERIC Educational Resources Information Center

    Pepper, Roger S.; Drexler, John A., Jr.

    The first phase of the study was a 2 x 2 factorial design, with locus of control and instructional method (lecture and demonstration) as independent variables and honor point average (HPA) as the dependent variable. The second phase used correlational techniques to test the extent to which reading performance and traditional predictors of…

  5. "High" Achievers? Cannabis Access and Student Performance. CEP Discussion Paper No. 1340

    ERIC Educational Resources Information Center

    Marie, Olivier; Zölitz, Ulf

    2015-01-01

    This paper investigates how legal cannabis access affects student performance. Identification comes from an exceptional policy introduced in the city of Maastricht which discriminated legal access based on individuals' nationality. We apply a difference-in-difference approach using administrative panel data on over 54,000 course grades of local…

  6. Mayoral Governance and Student Achievement: How Mayor-Led Districts Are Improving School and Student Performance

    ERIC Educational Resources Information Center

    Wong, Kenneth K.; Shen, Francis X.

    2013-01-01

    Mayoral control and accountability is one of very few major education reforms that aim at governance coherence in this nation's highly fragmented urban school systems. A primary feature of mayoral governance is that it holds the office of the mayor accountable for school performance. As an institutional redesign, mayoral governance integrates…

  7. Aural Dictation Affects High Achievement in Sight Singing, Performance and Composition Skills

    ERIC Educational Resources Information Center

    Rogers, Melissa

    2013-01-01

    The nature of skill acquisition has long been of interest to music educators. This study considers the research context for relationships between aural dictation, sight singing, performance and composition skills. Then, relationships between these skill areas are quantitatively investigated using data from the Australian New South Wales Music 2…

  8. Paying Teachers According to Student Achievement: Questions regarding Pay-for-Performance Models in Public Education

    ERIC Educational Resources Information Center

    Caillier, James

    2010-01-01

    In an effort to correct for perceived deficiencies in the No Child Left Behind Act, value-added models were proposed as a way to find out how much students learned in schools and classrooms throughout the school year. What has garnered much controversy regarding the value-added model, however, is the attempt to link pay and tenure to performance.…

  9. Teacher Performance Pay Signals and Student Achievement: Are Signals Accurate, and How well Do They Work?

    ERIC Educational Resources Information Center

    Manzeske, David; Garland, Marshall; Williams, Ryan; West, Benjamin; Kistner, Alexandra Manzella; Rapaport, Amie

    2016-01-01

    High-performing teachers tend to seek out positions at more affluent or academically challenging schools, which tend to hire more experienced, effective educators. Consequently, low-income and minority students are more likely to attend schools with less experienced and less effective educators (see, for example, DeMonte & Hanna, 2014; Office…

  10. Believe, and you will achieve: changes over time in self-efficacy, engagement, and performance.

    PubMed

    Ouweneel, Else; Schaufeli, Wilmar B; Le Blanc, Pascale M

    2013-07-01

    In order to answer the question whether changes in students' self-efficacy levels co-vary with similar changes in engagement and performance, a field study and an experimental study were conducted among university students. In order to do this, we adopted a subgroup approach. We created "natural" (Study 1) and manipulated (Study 2) subgroups based upon their change in self-efficacy over time and examined whether these subgroups showed similar changes over time in engagement and performance. The results of both studies are partly in line with Social Cognitive Theory, in that they confirm that changes in self-efficacy may have a significant impact on students' changes in cognition and motivation (i.e. engagement), as well as behavior (i.e. performance). More specifically, our results show that students' increases/decreases in self-efficacy were related to corresponding increases/decreases in their study engagement and task performance over time. Examining the consequences of changes in students' self-efficacy levels seems promising, both for research and practice.

  11. A Cross-Sectional Evaluation of Student Achievement Using Standardized and Performance-Based Tests

    ERIC Educational Resources Information Center

    Pinter, Brad; Matchock, Robert L.; Charles, Eric P.; Balch, William R.

    2014-01-01

    Three groups of undergraduates (42 senior graduating psychology majors, 27 first-year premajors taking introductory psychology, and 24 first-year, high-performing nonmajors taking introductory psychology) completed the Psychology Major Field Test (MFT) and a short-answer (SA) essay test on reasoning about core knowledge in psychology. Graduating…

  12. Short Circuits or Superconductors? Effects of Group Composition on High-Achieving Students' Science Assessment Performance.

    ERIC Educational Resources Information Center

    Webb, Noreen M.; Nemer, Kariane Mari; Zuniga, Stephen

    2002-01-01

    Studied the effects of group ability composition (homogeneous versus heterogeneous) on group processes and outcomes for high-ability students completing science assessments. Results for 83 high ability students show the quality of group functioning serves as the strongest predictor of high-ability students' performance and explained much of the…

  13. Identifying Intellectually Superior Black Children.

    ERIC Educational Resources Information Center

    Ryan, Judith S.

    1983-01-01

    The effectiveness of several methods used to identify intellectually superior black children was evaluated. Findings suggest that less commonly used identification methods, such as parents' opinion and the Leiter International Performance Scale, may point out these children more accurately than do traditional measures. (Author/PP)

  14. Superior mesenteric artery syndrome.

    PubMed Central

    Ahmed, A. R.; Taylor, I.

    1997-01-01

    Superior mesenteric artery syndrome is a rare and controversial form of upper intestinal obstruction in which the third part of the duodenum is compressed by the overlying superior mesenteric artery. Any disease process decreasing the angle between the superior mesenteric artery and the abdominal aorta can result in the external compression of the duodenum and subsequent intestinal obstruction. The aetiology, presentation, investigation and management of this unusual condition are discussed. PMID:9497945

  15. Achieving supercomputer performance for neural net simulation with an array of digital signal processors

    SciTech Connect

    Muller, U.A.; Baumle, B.; Kohler, P.; Gunzinger, A.; Guggenbuhl, W.

    1992-10-01

    Music, a DSP-based system with a parallel distributed-memory architecture, provides enormous computing power yet retains the flexibility of a general-purpose computer. Reaching a peak performance of 2.7 Gflops at a significantly lower cost, power consumption, and space requirement than conventional supercomputers, Music is well suited to computationally intensive applications such as neural network simulation. 12 refs., 9 figs., 2 tabs.

  16. Recognition of staff nurse job performance and achievements: staff and manager perceptions.

    PubMed

    Cronin, S N; Becherer, D

    1999-01-01

    Recognition for job performance is central to staff nurse morale. However, little research has been done to identify recognition methods most valued by nurses themselves. The authors report results of a multisite survey conducted to compare staff and manager perceptions of meaningful recognition behaviors. They provide data for developing management interventions that may help to improve morale and increase retention. Given the financial constraints of the current environment, the nonmonetary recognition practices identified are of particular significance.

  17. Athlete Atypicity on the Edge of Human Achievement: Performances Stagnate after the Last Peak, in 1988

    PubMed Central

    Berthelot, Geoffroy; Tafflet, Muriel; El Helou, Nour; Len, Stéphane; Escolano, Sylvie; Guillaume, Marion; Nassif, Hala; Tolaïni, Julien; Thibault, Valérie; Desgorces, François Denis; Hermine, Olivier; Toussaint, Jean-François

    2010-01-01

    The growth law for the development of top athletes performances remains unknown in quantifiable sport events. Here we present a growth model for 41351 best performers from 70 track and field (T&F) and swimming events and detail their characteristics over the modern Olympic era. We show that 64% of T&F events no longer improved since 1993, while 47% of swimming events stagnated after 1990, prior to a second progression step starting in 2000. Since then, 100% of swimming events continued to progress. We also provide a measurement of the atypicity for the 3919 best performances (BP) of each year in every event. The secular evolution of this parameter for T&F reveals four peaks; the most recent (1988) followed by a major stagnation. This last peak may correspond to the most recent successful attempt to push forward human physiological limits. No atypicity trend is detected in swimming. The upcoming rarefaction of new records in sport may be delayed by technological innovations, themselves depending upon economical constraints. PMID:20098706

  18. When performance-approach goals predict academic achievement and when they do not: a social value approach.

    PubMed

    Dompnier, Benoît; Darnon, Céline; Butera, Fabrizio

    2013-09-01

    Research on achievement goal promotion at University has shown that performance-approach goals are perceived as a means to succeed at University (high social utility) but are not appreciated (low social desirability). We argue that such a paradox could explain why research has detected that performance-approach goals consistently predict academic grades. First-year psychology students answered a performance-approach goal scale with standard, social desirability and social utility instructions. Participants' grades were recorded at the end of the semester. Results showed that the relationship between performance-approach goals and grades was inhibited by the increase of these goals' social desirability and facilitated by the increase of their social utility, revealing that the predictive validity of performance-approach goals depends on social value.

  19. Motivation and Performance within a Collaborative Computer-Based Modeling Task: Relations between Students' Achievement Goal Orientation, Self-Efficacy, Cognitive Processing, and Achievement

    ERIC Educational Resources Information Center

    Sins, Patrick H. M.; van Joolingen, Wouter R.; Savelsbergh, Elwin R.; van Hout-Wolters, Bernadette

    2008-01-01

    Purpose of the present study was to test a conceptual model of relations among achievement goal orientation, self-efficacy, cognitive processing, and achievement of students working within a particular collaborative task context. The task involved a collaborative computer-based modeling task. In order to test the model, group measures of…

  20. A conceptual framework for achieving performance enhancing drug compliance in sport.

    PubMed

    Donovan, Robert J; Egger, Garry; Kapernick, Vicki; Mendoza, John

    2002-01-01

    There has been, and continues to be, widespread international concern about athletes' use of banned performance enhancing drugs (PEDs). This concern culminated in the formation of the World Anti-Doping Agency (WADA) in November 1999. To date, the main focus on controlling the use of PEDs has been on testing athletes and the development of tests to detect usage. Although athletes' beliefs and values are known to influence whether or not an athlete will use drugs, little is known about athletes' beliefs and attitudes, and the limited empirical literature shows little use of behavioural science frameworks to guide research methodology, results interpretation, and intervention implications. Mindful of this in preparing its anti-doping strategy for the 2000 Olympics, the Australian Sports Drug Agency (ASDA) in 1997 commissioned a study to assess the extent to which models of attitude-behaviour change in the public health/injury prevention literature had useful implications for compliance campaigns in the sport drug area. A preliminary compliance model was developed from three behavioural science frameworks: social cognition models; threat (or fear) appeals; and instrumental and normative approaches. A subsequent review of the performance enhancing drug literature confirmed that the overall framework was consistent with known empirical data, and therefore had at least face validity if not construct validity. The overall model showed six major inputs to an athlete's attitudes and intentions with respect to performance enhancing drug usage: personality factors, threat appraisal, benefit appraisal, reference group influences, personal morality and legitimacy. The model demonstrated that a comprehensive, fully integrated programme is necessary for maximal effect, and provides anti-doping agencies with a structured framework for strategic planning and implementing interventions. Programmes can be developed in each of the six major areas, with allocation of resources to each

  1. A conceptual framework for achieving performance enhancing drug compliance in sport.

    PubMed

    Donovan, Robert J; Egger, Garry; Kapernick, Vicki; Mendoza, John

    2002-01-01

    There has been, and continues to be, widespread international concern about athletes' use of banned performance enhancing drugs (PEDs). This concern culminated in the formation of the World Anti-Doping Agency (WADA) in November 1999. To date, the main focus on controlling the use of PEDs has been on testing athletes and the development of tests to detect usage. Although athletes' beliefs and values are known to influence whether or not an athlete will use drugs, little is known about athletes' beliefs and attitudes, and the limited empirical literature shows little use of behavioural science frameworks to guide research methodology, results interpretation, and intervention implications. Mindful of this in preparing its anti-doping strategy for the 2000 Olympics, the Australian Sports Drug Agency (ASDA) in 1997 commissioned a study to assess the extent to which models of attitude-behaviour change in the public health/injury prevention literature had useful implications for compliance campaigns in the sport drug area. A preliminary compliance model was developed from three behavioural science frameworks: social cognition models; threat (or fear) appeals; and instrumental and normative approaches. A subsequent review of the performance enhancing drug literature confirmed that the overall framework was consistent with known empirical data, and therefore had at least face validity if not construct validity. The overall model showed six major inputs to an athlete's attitudes and intentions with respect to performance enhancing drug usage: personality factors, threat appraisal, benefit appraisal, reference group influences, personal morality and legitimacy. The model demonstrated that a comprehensive, fully integrated programme is necessary for maximal effect, and provides anti-doping agencies with a structured framework for strategic planning and implementing interventions. Programmes can be developed in each of the six major areas, with allocation of resources to each

  2. Achieving Equivalent Academic Performance Between Campuses Using a Distributed Education Model

    PubMed Central

    McCall, Kenneth L.; Raehl, Cynthia L.; Smith, Quentin R.; Lockman, Paul R.

    2009-01-01

    Objectives To demonstrate that students in competency-based anatomy and pharmaceutical calculations courses performed similarly whether enrolled in the classes through distance education or face-to-face lectures. Methods Student outcomes data including module examination scores, final course grades, and student demographics data were collected, merged, and analyzed. Results Mean module examination final scores and final course grades did not significantly differ between students at the lecture site and students at the remote site. Conclusions The competency-based anatomy and pharmaceutical calculations courses, whether remote or at the lecture site, provided equitable learning opportunities and roughly equivalent learning outcomes for students. PMID:19777103

  3. Achieving Reproducible Performance of Electrochemical, Folding Aptamer-Based Sensors on Microelectrodes: Challenges and Prospects

    PubMed Central

    2015-01-01

    Combining specific recognition capabilities with the excellent spatiotemporal resolution of small electrodes represents a promising methodology in bioanalytical and chemical sensing. In this paper, we report the development of reproducible electrochemical, aptamer-based (E-AB) sensors on a gold microelectrode platform. Specifically, we develop microscale sensors (25 μm diameter) for two representative small molecule targets–adenosine triphosphate and tobramycin. Furthermore, we report on the challenges encountered at this size scale including small-magnitude signals and interference from the irreversible reduction of dissolved oxygen and present methods to circumvent these challenges. Through the electrochemical deposition of dendritic gold nanostructures, we demonstrate microscale sensors with improved performance by increasing signal-to-noise and consequently sensitivity. Finally, we report on the use of the nonspecific adsorption of serum proteins as an additional layer of surface passivation for stable sensor performance. The sensor development here represents general guidelines for fabricating electrochemical, folding aptamer-based sensors on small-scale electrodes. PMID:25337781

  4. Balance the Carrier Mobility To Achieve High Performance Exciplex OLED Using a Triazine-Based Acceptor.

    PubMed

    Hung, Wen-Yi; Chiang, Pin-Yi; Lin, Shih-Wei; Tang, Wei-Chieh; Chen, Yi-Ting; Liu, Shih-Hung; Chou, Pi-Tai; Hung, Yi-Tzu; Wong, Ken-Tsung

    2016-02-01

    A star-shaped 1,3,5-triazine/cyano hybrid molecule CN-T2T was designed and synthesized as a new electron acceptor for efficient exciplex-based OLED emitter by mixing with a suitable electron donor (Tris-PCz). The CN-T2T/Tris-PCz exciplex emission shows a high ΦPL of 0.53 and a small ΔET-S = -0.59 kcal/mol, affording intrinsically efficient fluorescence and highly efficient exciton up-conversion. The large energy level offsets between Tris-PCz and CN-T2T and the balanced hole and electron mobility of Tris-PCz and CN-T2T, respectively, ensuring sufficient carrier density accumulated in the interface for efficient generation of exciplex excitons. Employing a facile device structure composed as ITO/4% ReO3:Tris-PCz (60 nm)/Tris-PCz (15 nm)/Tris-PCz:CN-T2T(1:1) (25 nm)/CN-T2T (50 nm)/Liq (0.5 nm)/Al (100 nm), in which the electron-hole capture is efficient without additional carrier injection barrier from donor (or acceptor) molecule and carriers mobilities are balanced in the emitting layer, leads to a highly efficient green exciplex OLED with external quantum efficiency (EQE) of 11.9%. The obtained EQE is 18% higher than that of a comparison device using an exciplex exhibiting a comparable ΦPL (0.50), in which TCTA shows similar energy levels but higher hole mobility as compared with Tris-PCz. Our results clearly indicate the significance of mobility balance in governing the efficiency of exciplex-based OLED. Exploiting the Tris-PCz:CN-T2T exciplex as the host, we further demonstrated highly efficient yellow and red fluorescent OLEDs by doping 1 wt % Rubrene and DCJTB as emitter, achieving high EQE of 6.9 and 9.7%, respectively.

  5. Balance the Carrier Mobility To Achieve High Performance Exciplex OLED Using a Triazine-Based Acceptor.

    PubMed

    Hung, Wen-Yi; Chiang, Pin-Yi; Lin, Shih-Wei; Tang, Wei-Chieh; Chen, Yi-Ting; Liu, Shih-Hung; Chou, Pi-Tai; Hung, Yi-Tzu; Wong, Ken-Tsung

    2016-02-01

    A star-shaped 1,3,5-triazine/cyano hybrid molecule CN-T2T was designed and synthesized as a new electron acceptor for efficient exciplex-based OLED emitter by mixing with a suitable electron donor (Tris-PCz). The CN-T2T/Tris-PCz exciplex emission shows a high ΦPL of 0.53 and a small ΔET-S = -0.59 kcal/mol, affording intrinsically efficient fluorescence and highly efficient exciton up-conversion. The large energy level offsets between Tris-PCz and CN-T2T and the balanced hole and electron mobility of Tris-PCz and CN-T2T, respectively, ensuring sufficient carrier density accumulated in the interface for efficient generation of exciplex excitons. Employing a facile device structure composed as ITO/4% ReO3:Tris-PCz (60 nm)/Tris-PCz (15 nm)/Tris-PCz:CN-T2T(1:1) (25 nm)/CN-T2T (50 nm)/Liq (0.5 nm)/Al (100 nm), in which the electron-hole capture is efficient without additional carrier injection barrier from donor (or acceptor) molecule and carriers mobilities are balanced in the emitting layer, leads to a highly efficient green exciplex OLED with external quantum efficiency (EQE) of 11.9%. The obtained EQE is 18% higher than that of a comparison device using an exciplex exhibiting a comparable ΦPL (0.50), in which TCTA shows similar energy levels but higher hole mobility as compared with Tris-PCz. Our results clearly indicate the significance of mobility balance in governing the efficiency of exciplex-based OLED. Exploiting the Tris-PCz:CN-T2T exciplex as the host, we further demonstrated highly efficient yellow and red fluorescent OLEDs by doping 1 wt % Rubrene and DCJTB as emitter, achieving high EQE of 6.9 and 9.7%, respectively. PMID:26820247

  6. Avoiding superior tilt in reverse shoulder arthroplasty: a review of the literature and technical recommendations.

    PubMed

    Laver, Lior; Garrigues, Grant E

    2014-10-01

    Superior tilt of the baseplate component in reverse total shoulder arthroplasty leads to tensile baseplate forces and may be a contributor to early loosening. The risk factors for this implant malposition include inadequate exposure through a superior approach and superior glenoid bone deficiency that obscures the native glenoid tilt. Here we review our preoperative evaluation and surgical management strategies to avoid superior tilt. Adequate exposure with a superior approach can be achieved but requires not just proper surgical technique but also careful patient selection. We propose that the superior approach be considered only for acute proximal humerus fractures or in patients when the following criteria are met: no prior open surgery on the shoulder; more than 30° of passive external rotation at 0° of abduction; no medial humeral osteophytes; and any superior migration must be reducible with a sulcus test during examination under anesthesia. Avoiding superior tilt when there is significant superior glenoid erosion can be accomplished with humeral head autograft, most easily performed through a deltopectoral approach. Preoperative templating is critical to determine proper graft thickness, inclination, reaming depth, and harvest technique. PMID:25220202

  7. Tuning interactions between zeolite and supported metal by physical-sputtering to achieve higher catalytic performances

    PubMed Central

    Li, Xin-Gang; Liu, Cheng; Sun, Jian; Xian, Hui; Tan, Yi-Sheng; Jiang, Zheng; Taguchi, Akira; Inoue, Mitsuhiro; Yoneyama, Yoshiharu; Abe, Takayuki; Tsubaki, Noritatsu

    2013-01-01

    To substitute for petroleum, Fischer-Tropsch synthesis (FTS) is an environmentally benign process to produce synthetic diesel (n-paraffin) from syngas. Industrially, the synthetic gasoline (iso-paraffin) can be produced with a FTS process followed by isomerization and hydrocracking processes over solid-acid catalysts. Herein, we demonstrate a cobalt nano-catalyst synthesized by physical-sputtering method that the metallic cobalt nano-particles homogeneously disperse on the H-ZSM5 zeolite support with weak Metal-Support Interactions (MSI). This catalyst performed the high gasoline-range iso-paraffin productivity through the combined FTS, isomerization and hydrocracking reactions. The weak MSI results in the easy reducibility of the cobalt nano-particles; the high cobalt dispersion accelerates n-paraffin diffusion to the neighboring acidic sites on the H-ZSM5 support for isomerization and hydrocracking. Both factors guarantee its high CO conversion and iso-paraffin selectivity. This physical-sputtering technique to synthesize the supported metallic nano-catalyst is a promising way to solve the critical problems caused by strong MSI for various processes. PMID:24085106

  8. High-performance partially aligned semiconductive single-walled carbon nanotube transistors achieved with a parallel technique.

    PubMed

    Wang, Yilei; Pillai, Suresh Kumar Raman; Chan-Park, Mary B

    2013-09-01

    Single-walled carbon nanotubes (SWNTs) are widely thought to be a strong contender for next-generation printed electronic transistor materials. However, large-scale solution-based parallel assembly of SWNTs to obtain high-performance transistor devices is challenging. SWNTs have anisotropic properties and, although partial alignment of the nanotubes has been theoretically predicted to achieve optimum transistor device performance, thus far no parallel solution-based technique can achieve this. Herein a novel solution-based technique, the immersion-cum-shake method, is reported to achieve partially aligned SWNT networks using semiconductive (99% enriched) SWNTs (s-SWNTs). By immersing an aminosilane-treated wafer into a solution of nanotubes placed on a rotary shaker, the repetitive flow of the nanotube solution over the wafer surface during the deposition process orients the nanotubes toward the fluid flow direction. By adjusting the nanotube concentration in the solution, the nanotube density of the partially aligned network can be controlled; linear densities ranging from 5 to 45 SWNTs/μm are observed. Through control of the linear SWNT density and channel length, the optimum SWNT-based field-effect transistor devices achieve outstanding performance metrics (with an on/off ratio of ~3.2 × 10(4) and mobility 46.5 cm(2) /Vs). Atomic force microscopy shows that the partial alignment is uniform over an area of 20 × 20 mm(2) and confirms that the orientation of the nanotubes is mostly along the fluid flow direction, with a narrow orientation scatter characterized by a full width at half maximum (FWHM) of <15° for all but the densest film, which is 35°. This parallel process is large-scale applicable and exploits the anisotropic properties of the SWNTs, presenting a viable path forward for industrial adoption of SWNTs in printed, flexible, and large-area electronics.

  9. Achieving high performance polymer optoelectronic devices for high efficiency, long lifetime and low fabrication cost

    NASA Astrophysics Data System (ADS)

    Huang, Jinsong

    This thesis described three types of organic optoelectronic devices: polymer light emitting diodes (PLED), polymer photovoltaic solar cell, and organic photo detector. The research in this work focuses improving their performance including device efficiency, operation lifetime simplifying fabrication process. With further understanding in PLED device physics, we come up new device operation model and improved device architecture design. This new method is closely related to understanding of the science and physics at organic/metal oxide and metal oxide/metal interface. In our new device design, both material and interface are considered in order to confine and balance all injected carriers, which has been demonstrated very be successful in increasing device efficiency. We created two world records in device efficiency: 18 lm/W for white emission fluorescence PLED, 22 lm/W for red emission phosphorescence PLED. Slow solvent drying process has been demonstrated to significantly increase device efficiency in poly(3-hexylthiophene) (P3HT) and [6,6]-phenyl C 61-butyric acid methyl ester (PCBM) mixture polymer solar cell. From the mobility study by time of flight, the increase of efficiency can be well correlated to the improved carrier transport property due to P3HT crystallization during slow solvent drying. And it is found that, similar to PLED, balanced carrier mobility is essential in high efficient polymer solar cell. There is also a revolution in our device fabrication method. A unique device fabrication method is presented by an electronic glue based lamination process combined with interface modification as a one-step polymer solar cell fabrication process. It can completely skip the thermal evaporation process, and benefit device lifetime by several merits: no air reactive. The device obtained is metal free, semi-transparent, flexible, self-encapsulated, and comparable efficiency with that by regular method. We found the photomultiplication (PM) phenomenon in C

  10. Pre-transplant achievement of negativity in minimal residual disease and French-American-British L1 morphology predict superior outcome after allogeneic transplant for Philadelphia chromosome positive acute lymphoblastic leukemia: an analysis of Southeast Asian patients.

    PubMed

    Ma, Liyuan; Hao, Siguo; Diong, Colin; Goh, Yeow-Tee; Gopalakrishnan, Sathish; Ho, Aloysius; Hwang, William; Koh, Liang-Piu; Koh, Mickey; Lim, Zi-Yi; Loh, Yvonne; Poon, Michelle; Tan, Lip-Kun; Tan, Patrick; Linn, Yeh-Ching

    2015-05-01

    To better understand predictive factors and improve the clinical outcome of allogeneic transplant for patients with Philadelphia positive acute lymphoblastic leukemia, we analyzed 67 Southeast Asian patients transplanted in our institutions. Multivariate analysis showed that disease status before transplant, year of transplant and, interestingly, French-American-British (FAB) subtype had a significant impact on overall survival (OS) and non-relapse mortality. Patients who were minimal residual disease (MRD) negative at transplant had a 3-year OS of 73% compared to those who were MRD positive (45%) and refractory (0%). The 3-year cumulative incidence of relapse was 18% and 36% for the MRD negative and positive groups, respectively. FAB L1 subtype had a significantly superior 3-year OS of 63% vs. 29% for L2 subtype. Pre-transplant use of a tyrosine kinase inhibitor significantly improved outcomes in univariate but not multivariate analysis, as it served to induce more patients into MRD negativity, which was the factor that directly improved transplant outcome.

  11. Metrics, Dollars, and Systems Change: Learning from Washington State's Student Achievement Initiative to Design Effective Postsecondary Performance Funding Policies. A State Policy Brief

    ERIC Educational Resources Information Center

    Jenkins, Davis; Shulock, Nancy

    2013-01-01

    The Student Achievement Initiative (SAI), adopted by the Washington State Board for Community and Technical Colleges in 2007, is one of a growing number of performance funding programs that have been dubbed "performance funding 2.0." Unlike previous performance funding models, the SAI rewards colleges for students' intermediate achievements along…

  12. Writing superiority in cued recall.

    PubMed

    Fueller, Carina; Loescher, Jens; Indefrey, Peter

    2013-01-01

    In list learning paradigms with free recall, written recall has been found to be less susceptible to intrusions of related concepts than spoken recall when the list items had been visually presented. This effect has been ascribed to the use of stored orthographic representations from the study phase during written recall (Kellogg, 2001). In other memory retrieval paradigms, by contrast, either better recall for modality-congruent items or an input-independent writing superiority effect have been found (Grabowski, 2005). In a series of four experiments using a paired associate learning paradigm we tested (a) whether output modality effects on verbal recall can be replicated in a paradigm that does not involve the rejection of semantically related intrusion words, (b) whether a possible superior performance for written recall was due to a slower response onset for writing as compared to speaking in immediate recall, and (c) whether the performance in paired associate word recall was correlated with performance in an additional episodic memory recall task. We observed better written recall in the first half of the recall phase, irrespective of the modality in which the material was presented upon encoding. An explanation for this effect based on longer response latencies for writing and hence more time for memory retrieval could be ruled out by showing that the effect persisted in delayed response versions of the task. Although there was some evidence that stored additional episodic information may contribute to the successful retrieval of associate words, this evidence was only found in the immediate response experiments and hence is most likely independent from the observed output modality effect. In sum, our results from a paired associate learning paradigm suggest that superior performance for written vs. spoken recall cannot be (solely) explained in terms of additional access to stored orthographic representations from the encoding phase. Our findings rather

  13. Multimedia OC12 parallel interface using VCSEL array to achieve high-performance cost-effective optical interconnections

    NASA Astrophysics Data System (ADS)

    Chang, Edward S.

    1996-09-01

    ribbon cable, and MT connectors to achieve a high-performance, low-cost parallel link. A logical model of a multimedia server with parallel connections to an ATM switch, and to clients is presented. The design of the parallel optical link is analyzed. Furthermore, the link configured for testing, the test method, and test results are presented to confirm the analysis and to assure reliable link performance.

  14. A Comparison of Nannochloropsis salina Growth Performance in Two Outdoor Pond Designs: Conventional Raceways versus the ARID Pond with Superior Temperature Management

    DOE PAGES

    Crowe, Braden; Attalah, Said; Agrawal, Shweta; Waller, Peter; Ryan, Randy; Van Wagenen, Jon; Chavis, Aaron; Kyndt, John; Kacira, Murat; Ogden, Kim L.; et al

    2012-01-01

    The present study examines how climatic conditions and pond design affect the growth performance of microalgae. From January to April of 2011, outdoor batch cultures of Nannochloropsis salina were grown in three replicate 780 L conventional raceways, as well as in an experimental 7500 L algae raceway integrated design (ARID) pond. The ARID culture system utilizes a series of 8-20 cm deep basins and a 1.5 m deep canal to enhance light exposure and mitigate temperature variations and extremes. The ARID culture reached the stationary phase 27 days earlier than the conventional raceways, which can be attributed to its superiormore » temperature management and shallower basins. On a night when the air temperature dropped to -9°C, the water temperature was 18°C higher in the ARID pond than in the conventional raceways. Lipid and fatty acid content ranged from 16 to 25% and from 5 to15%, respectively, as a percentage of AFDW. Palmitic, palmitoleic, and eicosapentaenoic acids comprised the majority of fatty acids. While the ARID culture system achieved nearly double the volumetric productivity relative to the conventional raceways (0.023 versus 0.013 g L-1day-1), areal biomass productivities were of similar magnitude in both pond systems (3.47 versus 3.34 g m-2day-1), suggesting that the ARID pond design has to be further optimized, most likely by increasing the culture depth or operating at higher cell densities while maintaining adequate mixing.« less

  15. Phase Tuning of Nanostructured Gallium Oxide via Hybridization with Reduced Graphene Oxide for Superior Anode Performance in Li-Ion Battery: An Experimental and Theoretical Study.

    PubMed

    Patil, Sharad B; Kim, In Young; Gunjakar, Jayavant L; Oh, Seung Mi; Eom, Taedaehyeong; Kim, Hyungjun; Hwang, Seong-Ju

    2015-08-26

    The crystal phase of nanostructured metal oxide can be effectively controlled by the hybridization of gallium oxide with reduced graphene oxide (rGO) at variable concentrations. The change of the ratio of Ga2O3/rGO is quite effective in tailoring the crystal structure and morphology of nanostructured gallium oxide hybridized with rGO. This is the first example of the phase control of metal oxide through a change of the content of rGO hybridized. The calculations based on density functional theory (DFT) clearly demonstrate that the different surface formation energy and Ga local symmetry of Ga2O3 phases are responsible for the phase transition induced by the change of rGO content. The resulting Ga2O3-rGO nanocomposites show promising electrode performance for lithium ion batteries. The intermediate Li-Ga alloy phases formed during the electrochemical cycling are identified with the DFT calculations. Among the present Ga2O3-rGO nanocomposites, the material with mixed α-Ga2O3/β-Ga2O3/γ-Ga2O3 phase can deliver the largest discharge capacity with the best cyclability and rate characteristics, highlighting the importance of the control of Ga2O3/rGO ratio in optimizing the electrode activity of the composite materials. The present study underscores the usefulness of the phase-control of nanostructured metal oxides achieved by the change of rGO content in exploring novel functional nanocomposite materials. PMID:26258574

  16. Phase Tuning of Nanostructured Gallium Oxide via Hybridization with Reduced Graphene Oxide for Superior Anode Performance in Li-Ion Battery: An Experimental and Theoretical Study.

    PubMed

    Patil, Sharad B; Kim, In Young; Gunjakar, Jayavant L; Oh, Seung Mi; Eom, Taedaehyeong; Kim, Hyungjun; Hwang, Seong-Ju

    2015-08-26

    The crystal phase of nanostructured metal oxide can be effectively controlled by the hybridization of gallium oxide with reduced graphene oxide (rGO) at variable concentrations. The change of the ratio of Ga2O3/rGO is quite effective in tailoring the crystal structure and morphology of nanostructured gallium oxide hybridized with rGO. This is the first example of the phase control of metal oxide through a change of the content of rGO hybridized. The calculations based on density functional theory (DFT) clearly demonstrate that the different surface formation energy and Ga local symmetry of Ga2O3 phases are responsible for the phase transition induced by the change of rGO content. The resulting Ga2O3-rGO nanocomposites show promising electrode performance for lithium ion batteries. The intermediate Li-Ga alloy phases formed during the electrochemical cycling are identified with the DFT calculations. Among the present Ga2O3-rGO nanocomposites, the material with mixed α-Ga2O3/β-Ga2O3/γ-Ga2O3 phase can deliver the largest discharge capacity with the best cyclability and rate characteristics, highlighting the importance of the control of Ga2O3/rGO ratio in optimizing the electrode activity of the composite materials. The present study underscores the usefulness of the phase-control of nanostructured metal oxides achieved by the change of rGO content in exploring novel functional nanocomposite materials.

  17. The Effect of Retesting on End-of-Semester Performance in High School Chemistry at Three Levels of Previous Science Achievement.

    ERIC Educational Resources Information Center

    Deboer, George E.

    1981-01-01

    Examines whether retesting: (1) affects achievement of students (N=95) grouped according to previous achievement in science; and (2) influences students to delay studying and perform at a low level on initial tests. Also examines whether procrastination of retested students is affected by their achievement level. (DS)

  18. Quality of education predicts performance on the Wide Range Achievement Test-4th Edition Word Reading subtest.

    PubMed

    Sayegh, Philip; Arentoft, Alyssa; Thaler, Nicholas S; Dean, Andy C; Thames, April D

    2014-12-01

    The current study examined whether self-rated education quality predicts Wide Range Achievement Test-4th Edition (WRAT-4) Word Reading subtest and neurocognitive performance, and aimed to establish this subtest's construct validity as an educational quality measure. In a community-based adult sample (N = 106), we tested whether education quality both increased the prediction of Word Reading scores beyond demographic variables and predicted global neurocognitive functioning after adjusting for WRAT-4. As expected, race/ethnicity and education predicted WRAT-4 reading performance. Hierarchical regression revealed that when including education quality, the amount of WRAT-4's explained variance increased significantly, with race/ethnicity and both education quality and years as significant predictors. Finally, WRAT-4 scores, but not education quality, predicted neurocognitive performance. Results support WRAT-4 Word Reading as a valid proxy measure for education quality and a key predictor of neurocognitive performance. Future research should examine these findings in larger, more diverse samples to determine their robust nature.

  19. Case study: Comparison of motivation for achieving higher performance between self-directed and manager-directed aerospace engineering teams

    NASA Astrophysics Data System (ADS)

    Erlick, Katherine

    "The stereotype of engineers is that they are not people oriented; the stereotype implies that engineers would not work well in teams---that their task emphasis is a solo venture and does not encourage social aspects of collaboration" (Miner & Beyerlein, 1999, p. 16). The problem is determining the best method of providing a motivating environment where design engineers may contribute within a team in order to achieve higher performance in the organization. Theoretically, self-directed work teams perform at higher levels. But, allowing a design engineer to contribute to the team while still maintaining his or her anonymity is the key to success. Therefore, a motivating environment must be established to encourage greater self-actualization in design engineers. The purpose of this study is to determine the favorable motivational environment for design engineers and describe the comparison between two aerospace design-engineering teams: one self-directed and the other manager directed. Following the comparison, this study identified whether self-direction or manager-direction provides the favorable motivational environment for operating as a team in pursuit of achieving higher performance. The methodology used in this research was the case study focusing on the team's levels of job satisfaction and potential for higher performance. The collection of data came from three sources, (a) surveys, (b) researcher observer journal and (c) collection of artifacts. The surveys provided information regarding personal behavior characteristics, potentiality for higher performance and motivational attributes. The researcher journal provided information regarding team dynamics, individual interaction, conflict and conflict resolution. The milestone for performance was based on the collection of artifacts from the two teams. The findings from this study illustrated that whether the team was manager-directed or self-directed does not appear to influence the needs and wants of the

  20. Functional Organosulfide Electrolyte Promotes an Alternate Reaction Pathway to Achieve High Performance in Lithium-Sulfur Batteries.

    PubMed

    Chen, Shuru; Dai, Fang; Gordin, Mikhail L; Yu, Zhaoxin; Gao, Yue; Song, Jiangxuan; Wang, Donghai

    2016-03-18

    Lithium-sulfur (Li-S) batteries have recently received great attention because they promise to provide energy density far beyond current lithium ion batteries. Typically, Li-S batteries operate by conversion of sulfur to reversibly form different soluble lithium polysulfide intermediates and insoluble lithium sulfides through multistep redox reactions. Herein, we report a functional electrolyte system incorporating dimethyl disulfide as a co-solvent that enables a new electrochemical reduction pathway for sulfur cathodes. This pathway uses soluble dimethyl polysulfides and lithium organosulfides as intermediates and products, which can boost cell capacity and lead to improved discharge-charge reversibility and cycling performance of sulfur cathodes. This electrolyte system can potentially enable Li-S batteries to achieve high energy density.

  1. A Heterojunction Design of Single Layer Hole Tunneling ZnO Passivation Wrapping around TiO2Nanowires for Superior Photocatalytic Performance.

    PubMed

    Ghobadi, Amir; Ulusoy, T Gamze; Garifullin, Ruslan; Guler, Mustafa O; Okyay, Ali K

    2016-01-01

    Nanostructured hybrid heterojunctions have been studied widely for photocatalytic applications due to their superior optical and structural properties. In this work, the impact of angstrom thick atomic layer deposited (ALD) ZnO shell layer on photocatalytic activity (PCA) of hydrothermal grown single crystalline TiO2 nanowires (NWs) is systematically explored. We showed that a single cycle of ALD ZnO layer wrapped around TiO2 NWs, considerably boosts the PCA of the heterostructure. Subsequent cycles, however, gradually hinder the photocatalytic activity (PCA) of the TiO2 NWs. Various structural, optical, and transient characterizations are employed to scrutinize this unprecedented change. We show that a single atomic layer of ZnO shell not only increases light harvesting capability of the heterostructure via extension of the absorption toward visible wavelengths, but also mitigates recombination probability of carriers through reduction of surface defects density and introduction of proper charge separation along the core-shell interface. Furthermore, the ultrathin ZnO shell layer allows a strong contribution of the core (TiO2) valence band holes through tunneling across the ultrathin interface. All mechanisms responsible for this enhanced PCA of heterostructure are elucidated and corresponding models are proposed. PMID:27464476

  2. Tuning superior solar cell performance of carrier mobility and absorption in perovskite CH3NH3GeCl3: A density functional calculations

    NASA Astrophysics Data System (ADS)

    Zhao, Yu-Qing; Wu, Li-Juan; Liu, Biao; Wang, Ling-Zhi; He, Peng-Bin; Cai, Meng-Qiu

    2016-05-01

    The solar cell based on hybrid organic-inorganic halide perovskite has received considerable attention. One of the most important issues in the pursuit of further developments in this area is to obtain both a high carrier mobility and an excellent ability of light adsorption. In this paper, we investigate the electronic structure and electronic effective masses of the new non-toxic material CH3NH3GeCl3 by first-principle calculations. The results show that the absorption efficiency of CH3NH3GeCl3 is more superior to that of CH3NH3PbI3 in short wavelength region. We trace this result to the ferroelectricity caused by the more serious octahedral GeCl6- distortion. We also discover a new relationship between the carrier effective masses anisotropy and the anisotropy of electronic density of states along three principal directions. Moreover, while applied the isotropic compressive pressure, the absorption efficiency and carrier mobility of CH3NH3GeCl3 in orthorhombic phase are improved greatly due to changes of electronic structure. We speculate that these are general results of tuning of the carrier mobility by controlling the band gap and the electronic occupation along different directions, to obtain both a high carrier mobility and an excellent ability of light adsorption.

  3. A Heterojunction Design of Single Layer Hole Tunneling ZnO Passivation Wrapping around TiO2Nanowires for Superior Photocatalytic Performance

    NASA Astrophysics Data System (ADS)

    Ghobadi, Amir; Ulusoy, T. Gamze; Garifullin, Ruslan; Guler, Mustafa O.; Okyay, Ali K.

    2016-07-01

    Nanostructured hybrid heterojunctions have been studied widely for photocatalytic applications due to their superior optical and structural properties. In this work, the impact of angstrom thick atomic layer deposited (ALD) ZnO shell layer on photocatalytic activity (PCA) of hydrothermal grown single crystalline TiO2 nanowires (NWs) is systematically explored. We showed that a single cycle of ALD ZnO layer wrapped around TiO2 NWs, considerably boosts the PCA of the heterostructure. Subsequent cycles, however, gradually hinder the photocatalytic activity (PCA) of the TiO2 NWs. Various structural, optical, and transient characterizations are employed to scrutinize this unprecedented change. We show that a single atomic layer of ZnO shell not only increases light harvesting capability of the heterostructure via extension of the absorption toward visible wavelengths, but also mitigates recombination probability of carriers through reduction of surface defects density and introduction of proper charge separation along the core-shell interface. Furthermore, the ultrathin ZnO shell layer allows a strong contribution of the core (TiO2) valence band holes through tunneling across the ultrathin interface. All mechanisms responsible for this enhanced PCA of heterostructure are elucidated and corresponding models are proposed.

  4. A Heterojunction Design of Single Layer Hole Tunneling ZnO Passivation Wrapping around TiO2Nanowires for Superior Photocatalytic Performance

    PubMed Central

    Ghobadi, Amir; Ulusoy, T. Gamze; Garifullin, Ruslan; Guler, Mustafa O.; Okyay, Ali K.

    2016-01-01

    Nanostructured hybrid heterojunctions have been studied widely for photocatalytic applications due to their superior optical and structural properties. In this work, the impact of angstrom thick atomic layer deposited (ALD) ZnO shell layer on photocatalytic activity (PCA) of hydrothermal grown single crystalline TiO2 nanowires (NWs) is systematically explored. We showed that a single cycle of ALD ZnO layer wrapped around TiO2 NWs, considerably boosts the PCA of the heterostructure. Subsequent cycles, however, gradually hinder the photocatalytic activity (PCA) of the TiO2 NWs. Various structural, optical, and transient characterizations are employed to scrutinize this unprecedented change. We show that a single atomic layer of ZnO shell not only increases light harvesting capability of the heterostructure via extension of the absorption toward visible wavelengths, but also mitigates recombination probability of carriers through reduction of surface defects density and introduction of proper charge separation along the core-shell interface. Furthermore, the ultrathin ZnO shell layer allows a strong contribution of the core (TiO2) valence band holes through tunneling across the ultrathin interface. All mechanisms responsible for this enhanced PCA of heterostructure are elucidated and corresponding models are proposed. PMID:27464476

  5. Ewe lambs with higher breeding values for growth achieve higher reproductive performance when mated at age 8 months.

    PubMed

    Nieto, C A Rosales; Ferguson, M B; Macleay, C A; Briegel, J R; Wood, D A; Martin, G B; Thompson, A N

    2013-09-15

    We studied the relationships among growth, body composition and reproductive performance in ewe lambs with known phenotypic values for depth of eye muscle (EMD) and fat (FAT) and Australian Sheep Breeding Values for post-weaning live weight (PWT) and depth of eye muscle (PEMD) and fat (PFAT). To detect estrus, vasectomized rams were placed with 190 Merino ewe lambs when on average they were 157 days old. The vasectomized rams were replaced with entire rams when the ewe lambs were, on average, 226 days old. Lambs were weighed every week and blood was sampled on four occasions for assay of ghrelin, leptin and ß-hydroxybutyrate. Almost 90% of the lambs attained puberty during the experiment, at an average live weight of 41.4 kg and average age of 197 days. Ewe lambs with higher values for EMD (P < 0.001), FAT (P < 0.01), PWT (P < 0.001), PEMD (P < 0.05) and PFAT (P < 0.05) were more likely to achieve puberty by 251 days of age. Thirty-six percent of the lambs conceived and, at the estimated date of conception, the average live weight was 46.9 ± 0.6 kg and average age was 273 days. Fertility, fecundity and reproductive rate were positively related to PWT (P < 0.05) and thus live weight at the start of mating (P < 0.001). Reproductive performance was not correlated with blood concentrations of ghrelin, leptin or ß-hydroxybutyrate. Many ewe lambs attained puberty, as detected by vasectomized rams, but then failed to become pregnant after mating with entire rams. Nevertheless, we can conclude that in ewe lambs mated at 8 months of age, higher breeding values for growth, muscle and fat are positively correlated with reproductive performance, although the effects of breeding values and responses to live weight are highly variable.

  6. Lake Superior, Duluth, MN

    NASA Technical Reports Server (NTRS)

    1973-01-01

    This view shows the west end of Lake Superior and Duluth, MN (47.0N, 91.0W). Portions of Minnesota, Michigan and Ontario, Canada are in the scene. The Duluth metropolitan area is at the west end of the lake. The discoloration plume in the water at Duluth is the result of tailings from the iron ore smelters that process the iron ore from the nearby open pit mines seen near the upper left corner of the photo.

  7. Predictive Indicators of High Performing Schools: A Study of Evaluative Inquiry and the Effective Use of Achievement Test Data

    ERIC Educational Resources Information Center

    Hill, Kathryn L.

    2010-01-01

    Existing research suggests a link between evaluative inquiry (EI) and student achievement, where EI is defined as the practice of analyzing student achievement data to identify ways to improve instruction. However, researchers lacked empirical evidence regarding the relationship between specific EI indicators and student achievement. The purpose…

  8. Significant Reading Experiences of Superior English Students.

    ERIC Educational Resources Information Center

    Whitman, Robert S.

    1964-01-01

    Superior high school students (975 finalists in the NCTE Achievement Awards Program) were surveyed to find what one book was most significant to each of them in their high school experiences, and the reason for the significance. In response to questionnaires, the students cited 416 different titles, 72% of which were novels. The top 10 books were…

  9. Leiomyosarcoma of the superior vena cava.

    PubMed

    de Chaumont, Arthus; Pierret, Charles; de Kerangal, Xavier; Le Moulec, Sylvestre; Laborde, François

    2014-08-01

    Leiomyosarcoma of the superior vena cava is a very rare tumor and only a few cases have been reported, with various techniques of vascular reconstruction. We describe a new case of leiomyosarcoma of the superior vena cava in a 61-year-old woman with extension to the brachiocephalic arterial trunk. Resection and vascular reconstruction were performed using, respectively, polytetrafluoroethylene and polyethylene terephtalate vascular grafts.

  10. Leiomyosarcoma of the superior vena cava.

    PubMed

    de Chaumont, Arthus; Pierret, Charles; de Kerangal, Xavier; Le Moulec, Sylvestre; Laborde, François

    2014-08-01

    Leiomyosarcoma of the superior vena cava is a very rare tumor and only a few cases have been reported, with various techniques of vascular reconstruction. We describe a new case of leiomyosarcoma of the superior vena cava in a 61-year-old woman with extension to the brachiocephalic arterial trunk. Resection and vascular reconstruction were performed using, respectively, polytetrafluoroethylene and polyethylene terephtalate vascular grafts. PMID:25087805

  11. Gender Differences in Achievement Goals and Performances in English Language and Mathematics of Senior Secondary Schools Students in Borno State, Nigeria

    ERIC Educational Resources Information Center

    Musa, Alice K. J.; Dauda, Bala; Umar, Mohammad A.

    2016-01-01

    The paper investigated gender difference in achievement goals and performance in English Language and Mathematics of senior secondary schools students in Borno State, Nigeria. The study specifically sought to determine gender differences in students' academic performances in English Language, Mathematics and overall academic performance as well as…

  12. Sex Differences in Performance Attributions, Self-Efficacy, and Achievement in Mathematics: If I'm So Smart, Why Don't I Know It?

    ERIC Educational Resources Information Center

    Lloyd, Jennifer E. V.; Walsh, John; Yailagh, Manizheh Shehni

    2005-01-01

    In this study, we tested the claim that sex differences in mathematics achievement are related to boys' and girls' differing achievement-related beliefs. We compared the mathematics report card grades, 2001 Foundation Skills Assessment (FSA) Numeracy subtest scores, performance attributions, and self-efficacy of 161 British Columbian public school…

  13. Achievement Gaps: How Hispanic and White Students in Public Schools Perform in Mathematics and Reading on the National Assessment of Educational Progress. Highlights. NCES 2011-485

    ERIC Educational Resources Information Center

    National Center for Education Statistics, 2011

    2011-01-01

    This report provides a detailed portrait of Hispanic and White academic achievement gaps and how students' performance has changed over time at both the national and state levels. The report presents achievement gaps using reading and mathematics assessment data from the National Assessment of Educational Progress (NAEP) for the 4th- and 8th-grade…

  14. Effects of Explicit Teaching and Peer Tutoring on the Reading Achievement of Learning-Disabled and Low-Performing Students in Regular Classrooms.

    ERIC Educational Resources Information Center

    Simmons, Deborah C.; And Others

    1995-01-01

    Examined effects of explicit teaching and peer tutoring on reading achievement of learning-disabled students and nondisabled, low-performing readers in academically integrated classrooms. Found that explicit-teaching students did not achieve reliably better than controls; students in the explicit teaching plus peer tutoring condition scored higher…

  15. The potential influence of perception of achievement on performance in volitional time-to-exhaustion cycle ergometer trials.

    PubMed

    Lorimer, Ross; Babraj, John

    2013-06-01

    The purpose of this short communication was to report the findings of an investigation of the potential influence of spontaneous goal setting on subjects undertaking maximal fitness testing. Subjects were asked to complete a single incremental volitional time-to-exhaustion cycle ergometer trial. The final minute of the trial, after the last increase in increment in resistance, was broken down into six 10-second intervals and a frequency count made of how many subjects stopped within each interval. A chi-square test was used to determine that there was a significant difference between the expected and the observed frequencies (p < 0.05), with 45% of subjects stopping in the first interval (0-10 seconds) and 0% within the last interval (51-60 seconds). Reflections of the subjects revealed that those who were close to exhaustion but near to reaching the next increment of resistance were more likely to "push on." However, despite having been told to keep going as long as they could, subjects upon reaching that increment stopped almost immediately as they believed they could not manage to reach the next increment. This suggests a potential psychological element related to goal achievement that influences performance in incremental volitional time-to-exhaustion cycle ergometer trials. Practically, this means that the information participants have available on which to base goals (level of increment, time, etc.) needs to be minimized to prevent spontaneous goal setting.

  16. 28 CFR 2.60 - Superior program achievement.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... applicable. 15 to 22 months Up to 1 month. 23 to 30 months Up to 2 months. 31 to 36 months Up to 3 months. 37 to 42 months Up to 4 months. 43 to 48 months Up to 5 months. 49 to 54 months Up to 6 months. 55 to 60... to 10 months. 79 to 84 months Up to 11 months. 85 to 90 months Up to 12 months. 91 plus months Up...

  17. Use corporate culture to trigger high performance.

    PubMed

    Bettinger, C

    1989-01-01

    The challenge is to manage the organization's culture so that you can tap the company's strengths to achieve superior performance and identify its weaknesses in time to overcome them before they cause serious damage.

  18. Superior oblique surgery: when and how?

    PubMed Central

    Şekeroğlu, Hande Taylan; Sanac, Ali Sefik; Arslan, Umut; Sener, Emin Cumhur

    2013-01-01

    Background The purpose of this paper is to review different types of superior oblique muscle surgeries, to describe the main areas in clinical practice where superior oblique surgery is required or preferred, and to discuss the preferred types of superior oblique surgery with respect to their clinical outcomes. Methods A consecutive nonrandomized retrospective series of patients who had undergone superior oblique muscle surgery as a single procedure were enrolled in the study. The diagnosis, clinical features, preoperative and postoperative vertical deviations in primary position, type of surgery, complications, and clinical outcomes were reviewed. The primary outcome measures were the type of strabismus and the type of superior oblique muscle surgery. The secondary outcome measure was the results of the surgeries. Results The review identified 40 (20 male, 20 female) patients with a median age of 6 (2–45) years. Nineteen patients (47.5%) had Brown syndrome, eleven (27.5%) had fourth nerve palsy, and ten (25.0%) had horizontal deviations with A pattern. The most commonly performed surgery was superior oblique tenotomy in 29 (72.5%) patients followed by superior oblique tuck in eleven (27.5%) patients. The amount of vertical deviation in the fourth nerve palsy and Brown syndrome groups (P = 0.01 for both) and the amount of A pattern in the A pattern group were significantly reduced postoperatively (P = 0.02). Conclusion Surgery for the superior oblique muscle requires experience and appropriate preoperative evaluation in view of its challenging nature. The main indications are Brown syndrome, fourth nerve palsy, and A pattern deviations. Superior oblique surgery may be effective in terms of pattern collapse and correction of vertical deviations in primary position. PMID:23946644

  19. Performance Assessment of High and Low Income Families through "Online RAW Achievement Battery Test" of Primary Grade Students

    ERIC Educational Resources Information Center

    Ahmed, Tamim; Hanif, Maria

    2016-01-01

    This study is intended to investigate student's achievement capability among two families i.e. Low and High income families and designed for primary level learners. A Reading, Arithmetic and Writing (RAW) Achievement test that was developed as a part of another research study (Tamim Ahmed Khan, 2015) was adopted for this study. Both English medium…

  20. Associative Verbal Encoding (a/v/e): A Measure of Language Performance and Its Relationship to Reading Achievement.

    ERIC Educational Resources Information Center

    Mickelson, Norma Irene

    After establishing reliability for an associative verbal encoding (a/v/e) test, the relationship between children's a/v/e and their reading achievement was investigated. Two hypotheses were examined: (1) a/v/e will improve with training, and (2) associated with improved a/v/e will be concomitant improvement in reading achievement. The subjects…

  1. Development and Validation of a Physics Achievement Test to Identify Instructor Variables Associated with Students' Physics Academic Performance

    ERIC Educational Resources Information Center

    Lacambra, Wilfredo T.

    2016-01-01

    One of the most common ways of detecting whether an improvement is achieved by an education institution is through measuring the students' achievement in a test. Testing is generally thought of as a means of assessing the knowledge and skills students have acquired through learning (Du-chastel and Nungester, 1998). Test results, besides assisting…

  2. A Multi-Institutional Study of the Relationship between High School Mathematics Achievement and Performance in Introductory College Statistics

    ERIC Educational Resources Information Center

    Dupuis, Danielle N.; Medhanie, Amanuel; Harwell, Michael; LeBeau, Brandon; Monson, Debra; Post, Thomas R.

    2012-01-01

    In this study we examined the effects of prior mathematics achievement and completion of a commercially developed, National Science Foundation-funded, or University of Chicago School Mathematics Project high school mathematics curriculum on achievement in students' first college statistics course. Specifically, we examined the relationship between…

  3. Porous nitrogen-doped carbon derived from silk fibroin protein encapsulating sulfur as a superior cathode material for high-performance lithium-sulfur batteries

    NASA Astrophysics Data System (ADS)

    Zhang, Jiawei; Cai, Yurong; Zhong, Qiwei; Lai, Dongzhi; Yao, Juming

    2015-10-01

    The features of a carbon substrate are crucial for the electrochemical performance of lithium-sulfur (Li-S) batteries. Nitrogen doping of carbon materials is assumed to play an important role in sulfur immobilisation. In this study, natural silk fibroin protein is used as a precursor of nitrogen-rich carbon to fabricate a novel, porous, nitrogen-doped carbon material through facile carbonisation and activation. Porous carbon, with a reversible capacity of 815 mA h g-1 at 0.2 C after 60 cycles, serves as the cathode material in Li-S batteries. Porous carbon retains a reversible capacity of 567 mA h g-1, which corresponds to a capacity retention of 98% at 1 C after 200 cycles. The promising electrochemical performance of porous carbon is attributed to its mesoporous structure, high specific surface area and nitrogen doping into the carbon skeleton. This study provides a general strategy to synthesise nitrogen-doped carbons with a high specific surface area, which is crucial to improve the energy density and electrochemical performance of Li-S batteries.

  4. Fog-like fluffy structured N-doped carbon with a superior oxygen reduction reaction performance to a commercial Pt/C catalyst.

    PubMed

    You, Chenghang; Zen, Xiaoyuan; Qiao, Xiaochang; Liu, Fangfang; Shu, Ting; Du, Li; Zeng, Jianhuang; Liao, Shijun

    2015-02-28

    A high-performance N-doped carbon catalyst with a fog-like, fluffy structure was prepared through pyrolyzing a mixture of polyacrylonitrile, melamine and iron chloride. The catalyst exhibits an excellent oxygen reduction reaction (ORR) performance, with a half-wave potential 27 mV more positive than that of a commercial Pt/C catalyst (-0.120 vs. -0.147 V) and a higher diffusion-limiting current density than that of Pt/C (5.60 vs. 5.33 mA cm(-2)) in an alkaline medium. Moreover, it also shows outstanding methanol tolerance, remarkable stability and nearly 100% selectivity for the four-electron ORR process. To our knowledge, it is one of the most active doped carbon ORR catalysts in alkaline media to date. By comparing catalysts derived from precursors containing different amounts of melamine, we found that the added melamine not only gives the catalyst a fluffy structure but also modifies the N content and the distribution of N species in the catalyst, which we believe to be the origins for the catalyst's excellent ORR performance.

  5. Porous nitrogen-doped carbon derived from silk fibroin protein encapsulating sulfur as a superior cathode material for high-performance lithium-sulfur batteries.

    PubMed

    Zhang, Jiawei; Cai, Yurong; Zhong, Qiwei; Lai, Dongzhi; Yao, Juming

    2015-11-14

    The features of a carbon substrate are crucial for the electrochemical performance of lithium-sulfur (Li-S) batteries. Nitrogen doping of carbon materials is assumed to play an important role in sulfur immobilisation. In this study, natural silk fibroin protein is used as a precursor of nitrogen-rich carbon to fabricate a novel, porous, nitrogen-doped carbon material through facile carbonisation and activation. Porous carbon, with a reversible capacity of 815 mA h g(-1) at 0.2 C after 60 cycles, serves as the cathode material in Li-S batteries. Porous carbon retains a reversible capacity of 567 mA h g(-1), which corresponds to a capacity retention of 98% at 1 C after 200 cycles. The promising electrochemical performance of porous carbon is attributed to its mesoporous structure, high specific surface area and nitrogen doping into the carbon skeleton. This study provides a general strategy to synthesise nitrogen-doped carbons with a high specific surface area, which is crucial to improve the energy density and electrochemical performance of Li-S batteries.

  6. A carbon coated NASICON structure material embedded in porous carbon enabling superior sodium storage performance: NaTi2(PO4)3 as an example.

    PubMed

    Jiang, Yu; Zeng, Linchao; Wang, Jiaqing; Li, Weihan; Pan, Fusen; Yu, Yan

    2015-09-21

    Sodium super ion conductor (NASICON) type structure materials (e.g. Na3V2(PO4)3, NaTi2(PO4)3) have been considered as promising electrode materials for sodium-ion batteries (NIBs). However, the inherent poor electronic conductivity of the NASICON type structure materials owing to their poor electronic conductivity of phosphates leads to poor cyclability and rate capability. Here, we develop a general strategy to achieve high rate capability and long cycle life by preparing "double carbon coating" NASICON NaTi2(PO4)3 using a soft-chemical method. The obtained carbon-coated NaTi2(PO4)3 within the porous carbon matrix (denoted as NTP@C@PC) imparts a reversible capability of 103 mA h g(-1) at 5 C after 5000 cycles and a rate capability of 64 mA h g(-1) at 50 C for sodium storage. The high capacity, stable cyclability and excellent rate capability of the NTP@C@PC are attributed to the advantages of the special structure: the fast Na(+)/e(-) transfer in the nanocomposites, large surface area and mesoporous nature of the 3D porous carbon matrix that facilitate the electrolyte to soak in, an intimate interaction between the particles and the carbon matrix. In addition, the 3D porous carbon matrix could effectively accommodate the volume variation during a repeated sodiation/desodiation process. PMID:26284915

  7. A carbon coated NASICON structure material embedded in porous carbon enabling superior sodium storage performance: NaTi2(PO4)3 as an example.

    PubMed

    Jiang, Yu; Zeng, Linchao; Wang, Jiaqing; Li, Weihan; Pan, Fusen; Yu, Yan

    2015-09-21

    Sodium super ion conductor (NASICON) type structure materials (e.g. Na3V2(PO4)3, NaTi2(PO4)3) have been considered as promising electrode materials for sodium-ion batteries (NIBs). However, the inherent poor electronic conductivity of the NASICON type structure materials owing to their poor electronic conductivity of phosphates leads to poor cyclability and rate capability. Here, we develop a general strategy to achieve high rate capability and long cycle life by preparing "double carbon coating" NASICON NaTi2(PO4)3 using a soft-chemical method. The obtained carbon-coated NaTi2(PO4)3 within the porous carbon matrix (denoted as NTP@C@PC) imparts a reversible capability of 103 mA h g(-1) at 5 C after 5000 cycles and a rate capability of 64 mA h g(-1) at 50 C for sodium storage. The high capacity, stable cyclability and excellent rate capability of the NTP@C@PC are attributed to the advantages of the special structure: the fast Na(+)/e(-) transfer in the nanocomposites, large surface area and mesoporous nature of the 3D porous carbon matrix that facilitate the electrolyte to soak in, an intimate interaction between the particles and the carbon matrix. In addition, the 3D porous carbon matrix could effectively accommodate the volume variation during a repeated sodiation/desodiation process.

  8. Superior performance of metal-organic frameworks over zeolites as solid acid catalysts in the Prins reaction: green synthesis of nopol.

    PubMed

    Opanasenko, Maksym; Dhakshinamoorthy, Amarajothi; Hwang, Young Kyu; Chang, Jong-San; Garcia, Hermenegildo; Čejka, Jiří

    2013-05-01

    The catalytic performance of a set of metal-organic frameworks [CuBTC, FeBTC, MIL-100(Fe), MIL-100(Cr), ZIF-8, MIL-53(Al)] was investigated in the Prins condensation of β-pinene with formaldehyde and compared with the catalytic behavior of conventional aluminosilicate zeolites BEA and FAU and titanosilicate zeolite MFI (TS-1). The activity of the investigated metal-organic frameworks (MOFs) increased with the increasing concentration of accessible Lewis acid sites in the order ZIF-8performing catalyst of the series for the Prins condensation of β-pinene and paraformaldehyde. Our report exemplifies the advantages of MOFs over zeolites as solid catalysts in liquid-phase reactions for the production of fine chemicals.

  9. T’ain’t what you say, it’s the way that you say it – left insula and inferior frontal cortex work in interaction with superior temporal regions to control the performance of vocal impersonations

    PubMed Central

    McGettigan, Carolyn; Eisner, Frank; Agnew, Zarinah K; Manly, Tom; Wisbey, Duncan; Scott, Sophie K

    2014-01-01

    Historically, the study of human identity perception has focused on faces, but the voice is also central to our expressions and experiences of identity (P. Belin, Fecteau, & Bedard, 2004). Our voices are highly flexible and dynamic; talkers speak differently depending on their health, emotional state, and the social setting, as well as extrinsic factors such as background noise. However, to date, there have been no studies of the neural correlates of identity modulation in speech production. In the current fMRI experiment, we measured the neural activity supporting controlled voice change in adult participants performing spoken impressions. We reveal that deliberate modulation of vocal identity recruits the left anterior insula and inferior frontal gyrus, supporting the planning of novel articulations. Bilateral sites in posterior superior temporal/inferior parietal cortex and a region in right mid/anterior superior temporal sulcus showed greater responses during the emulation of specific vocal identities than for impressions of generic accents. Using functional connectivity analyses, we describe roles for these three sites in their interactions with the brain regions supporting speech planning and production. Our findings mark a significant step toward understanding the neural control of vocal identity, with wider implications for the cognitive control of voluntary motor acts. PMID:23691984

  10. WWC Review of the Report "Daily Online Testing in Large Classes: Boosting College Performance While Reducing Achievement Gaps." What Works Clearinghouse Single Study Review

    ERIC Educational Resources Information Center

    What Works Clearinghouse, 2014

    2014-01-01

    The 2013 study, "Daily Online Testing in Large Classes: Boosting College Performance While Reducing Achievement Gaps," examined the impact of frequent online testing and immediate feedback on the academic performance of college students. The study was conducted at the University of Texas in the fall of 2008 and 2011. Researchers found…

  11. Correlations among Six Learner Variables and the Performance of a Sample of Jamaican Eleventh-Graders on an Achievement Test on Respiration

    ERIC Educational Resources Information Center

    Soyibo, Kola; Pinnock, Jacqueline

    2005-01-01

    This study aimed at establishing if the level of performance of 500 Jamaican Grade 11 students on an achievement test on the concept of respiration was satisfactory (mean = 28 or 70% and above) or not (less than 70%); if there were statistically significant differences in their performance on the concept linked to their gender, cognitive abilities…

  12. Lake Superior revisited 1984

    USGS Publications Warehouse

    MacCallum, Wayne R.; Selgeby, James H.

    1987-01-01

    The Lake Superior fish community has changed substantially since the early 1960s, when control of the sea lamprey (Petromyzon marinus) became effective. Self-reproducing stocks of lake trout (Salvelinus namaycush) have been reestablished in many inshore areas, although they have not yet reached pre-sea lamprey abundance; offshore lake trout are probably at or near pre-sea lamprey abundance. Stocks of lake whitefish (Coregonus clupeaformis) appear to have fully recovered; commercial catches are at or above historical levels. Lake herring (Coregonus artedii) are recovering rapidly in U.S. waters and are abundant in western Canadian waters. The population of rainbow smelt (Osmerus mordax), which declined in the 1970s, is recovering. Pacific salmon (Oncorhynchus) are becoming more abundant as a result of increased stocking in U.S. waters and are reproducing in most suitable tributaries; they have become significant in anglers' creels.

  13. Magnetic resonance imaging evaluation of meniscoid superior labrum: normal variant or superior labral tear*

    PubMed Central

    Simão, Marcelo Novelino; Vinson, Emily N.; Spritzer, Charles E.

    2016-01-01

    Objective The objective of this study was to determine the incidence of a "meniscoid" superior labrum. Materials and Methods This was a retrospective analysis of 582 magnetic resonance imaging examinations of shoulders. Of those 582 examinations, 110 were excluded, for a variety of reasons, and the final analysis therefore included 472 cases. Consensus readings were performed by three musculoskeletal radiologists using specific criteria to diagnose meniscoid labra. Results A meniscoid superior labrum was identified in 48 (10.2%) of the 472 cases evaluated. Arthroscopic proof was available in 21 cases (43.8%). In 10 (47.6%) of those 21 cases, the operative report did not include the mention a superior labral tear, thus suggesting the presence of a meniscoid labrum. In only one of those cases were there specific comments about a mobile superior labrum (i.e., meniscoid labrum). In the remaining 11 (52.4%), surgical correlation demonstrated superior labral tears. Conclusion A meniscoid superior labrum is not an infrequent finding. Depending upon assumptions and the requirement of surgical proof, the prevalence of a meniscoid superior labrum in this study was between 2.1% (surgically proven) and 4.8% (projected). However, superior labral tears are just as common and are often confused with meniscoid labra. PMID:27777474

  14. Superior electrochemical performance of LiCoO2 electrodes enabled by conductive Al2O3-doped ZnO coating via magnetron sputtering

    NASA Astrophysics Data System (ADS)

    Dai, Xinyi; Zhou, Aijun; Xu, Jin; Yang, Bin; Wang, Liping; Li, Jingze

    2015-12-01

    A conductive Al2O3-doped ZnO (AZO) layer is coated directly on the LiCoO2 (LCO) porous composite electrode by magnetron sputtering of an AZO target, offering more efficient electron transfer and a stabilized interface layer. Up to 90% of the initial capacity of the AZO-coated electrode can be retained (173 mAh g-1) after 150 cycles between 3.0 and 4.5 V vs. Li/Li+. Meanwhile, the rate performance is remarkably improved showing a reversible capacity of 112 mAh g-1 at 12 C. The formation of amorphous solid electrolyte interface (SEI) observed on the uncoated LCO electrode is effectively impeded on the AZO-coated one. Acting as an intermediate barrier, the AZO layer can prevent chemical dissolution of the active materials by forming a thin passivation layer on the electrode surface containing some metal fluorides which are chemically inactive and ionically conductive. The positive role of the AZO coating is still effective under a more severe condition tested with an upper cut-off potential of 4.7 V.

  15. Waste-Glycerol-Directed Synthesis of Mesoporous Silica and Carbon with Superior Performance in Room-Temperature Hydrogen Production from Formic Acid

    PubMed Central

    Lee, Dong-Wook; Jin, Min-Ho; Park, Ji Chan; Lee, Chun-Boo; Oh, Duckkyu; Lee, Sung-Wook; Park, Jin-Woo; Park, Jong-Soo

    2015-01-01

    The development of easier, cheaper, and more ecofriendly synthetic methods for mesoporous materials remains a challenging topic to commercialize them, and the transformation of waste glycerol, as a biodiesel byproduct, into something useful and salable is one of the pending issues to be resolved. Here we first report that mesoporous silica (KIE-6) and carbon (KIE-7) can be simultaneously synthesized by using cheap and ecofriendly crude-waste-glycerol of biodiesel with or without glycerol purification, and we demonstrated the excellent performance of the mesoporous material as a catalyst support for formic acid decomposition. As a result, Pd-MnOx catalysts supported on NH2-functionalized KIE-6 showed the highest catalytic activity (TOF: 540.6 h−1) ever reported for room-temperature formic acid decomposition without additives. Moreover, we conducted life-cycle assessment (LCA) from biomass cultivation through biodiesel production to KIE-6 and KIE-7 preparation, and it was confirmed that CO2 emission during synthesis of KIE-6 and KIE-7 could be reduced by 87.1% and 85.7%, respectively. We believe that our study suggested more ecofriendly and industry-friendly approaches for preparation of mesoporous materials, and utilization of waste glycerol. PMID:26515193

  16. Waste-Glycerol-Directed Synthesis of Mesoporous Silica and Carbon with Superior Performance in Room-Temperature Hydrogen Production from Formic Acid

    NASA Astrophysics Data System (ADS)

    Lee, Dong-Wook; Jin, Min-Ho; Park, Ji Chan; Lee, Chun-Boo; Oh, Duckkyu; Lee, Sung-Wook; Park, Jin-Woo; Park, Jong-Soo

    2015-10-01

    The development of easier, cheaper, and more ecofriendly synthetic methods for mesoporous materials remains a challenging topic to commercialize them, and the transformation of waste glycerol, as a biodiesel byproduct, into something useful and salable is one of the pending issues to be resolved. Here we first report that mesoporous silica (KIE-6) and carbon (KIE-7) can be simultaneously synthesized by using cheap and ecofriendly crude-waste-glycerol of biodiesel with or without glycerol purification, and we demonstrated the excellent performance of the mesoporous material as a catalyst support for formic acid decomposition. As a result, Pd-MnOx catalysts supported on NH2-functionalized KIE-6 showed the highest catalytic activity (TOF: 540.6 h-1) ever reported for room-temperature formic acid decomposition without additives. Moreover, we conducted life-cycle assessment (LCA) from biomass cultivation through biodiesel production to KIE-6 and KIE-7 preparation, and it was confirmed that CO2 emission during synthesis of KIE-6 and KIE-7 could be reduced by 87.1% and 85.7%, respectively. We believe that our study suggested more ecofriendly and industry-friendly approaches for preparation of mesoporous materials, and utilization of waste glycerol.

  17. Superior adsorption performance for triphenylmethane dyes on 3D architectures assembled by ZnO nanosheets as thin as ∼1.5nm.

    PubMed

    Pei, Cuijin; Han, Guoping; Zhao, Yan; Zhao, Hua; Liu, Bin; Cheng, Lijuan; Yang, Heqing; Liu, Shengzhong

    2016-11-15

    The 3-dimensional hierarchical ZnO flower-like architectures have been synthesized in a Zn(Ac)2·2H2O-Na2SeO3-KBH4-pyridine solvothermal system at 100°C for 24h. The flower-like architecture is assembled from ZnO nanosheets with a thickness of ∼1.5nm, and the flower-like architecture specific surface area is 132m(2)/g. When the ZnO flower-like architecture is used as the adsorbent for acid fuschin (AF), malachite green (MG), basic fuchsin (BF), congo red (CR) and acid red (AR) in water, the adsorption capacities for AF, MG, BF, CR and AR are 7154.9, 2587.0, 1377.9, 85.0 and 38.0mg/g, respectively. Evidently, the as-obtained ZnO flower-like architectures show excellent adsorption performances for triphenylmethane dyes, and the adsorption capacity of 7154.9mg/g for AF is the highest of all adsorbents for dyes. The adsorption mechanism can be attributed to the electrostatic attraction and the formation of ion-association complex between triphenylmethane dyes and ZnO hierarchical flower-like architectures. PMID:27493012

  18. Waste-Glycerol-Directed Synthesis of Mesoporous Silica and Carbon with Superior Performance in Room-Temperature Hydrogen Production from Formic Acid.

    PubMed

    Lee, Dong-Wook; Jin, Min-Ho; Park, Ji Chan; Lee, Chun-Boo; Oh, Duckkyu; Lee, Sung-Wook; Park, Jin-Woo; Park, Jong-Soo

    2015-01-01

    The development of easier, cheaper, and more ecofriendly synthetic methods for mesoporous materials remains a challenging topic to commercialize them, and the transformation of waste glycerol, as a biodiesel byproduct, into something useful and salable is one of the pending issues to be resolved. Here we first report that mesoporous silica (KIE-6) and carbon (KIE-7) can be simultaneously synthesized by using cheap and ecofriendly crude-waste-glycerol of biodiesel with or without glycerol purification, and we demonstrated the excellent performance of the mesoporous material as a catalyst support for formic acid decomposition. As a result, Pd-MnOx catalysts supported on NH2-functionalized KIE-6 showed the highest catalytic activity (TOF: 540.6 h(-1)) ever reported for room-temperature formic acid decomposition without additives. Moreover, we conducted life-cycle assessment (LCA) from biomass cultivation through biodiesel production to KIE-6 and KIE-7 preparation, and it was confirmed that CO2 emission during synthesis of KIE-6 and KIE-7 could be reduced by 87.1% and 85.7%, respectively. We believe that our study suggested more ecofriendly and industry-friendly approaches for preparation of mesoporous materials, and utilization of waste glycerol. PMID:26515193

  19. MnO(x) Nanoparticle-Dispersed CeO2 Nanocubes: A Remarkable Heteronanostructured System with Unusual Structural Characteristics and Superior Catalytic Performance.

    PubMed

    Putla, Sudarsanam; Amin, Mohamad Hassan; Reddy, Benjaram M; Nafady, Ayman; Al Farhan, Khalid A; Bhargava, Suresh K

    2015-08-01

    Understanding the interface-induced effects of heteronanostructured catalysts remains a significant challenge due to their structural complexity, but it is crucial for developing novel applied catalytic materials. This work reports a systematic characterization and catalytic evaluation of MnOx nanoparticle-dispersed CeO2 nanocubes for two important industrial applications, namely, diesel soot oxidation and continuous-flow benzylamine oxidation. The X-ray diffraction and Raman studies reveal an unusual lattice expansion in CeO2 after the addition of MnOx. This interesting observation is due to conversion of smaller sized Ce(4+) (0.097 nm) to larger sized Ce(3+) (0.114 nm) in cerium oxide led by the strong interaction between MnOx and CeO2 at their interface. Another striking observation noticed from transmission electron microscopy, high angle annular dark-field scanning transmission electron microscopy, and electron energy loss spectroscopy studies is that the MnOx species are well-dispersed along the edges of the CeO2 nanocubes. This remarkable decoration leads to an enhanced reducible nature of the cerium oxide at the MnOx/CeO2 interface. It was found that MnOx/CeO2 heteronanostructures efficiently catalyze soot oxidation at lower temperatures (50% soot conversion, T50 ∼660 K) compared with that of bare CeO2 nanocubes (T50 ∼723 K). Importantly, the MnOx/CeO2 heteronanostructures exhibit a noticeable steady performance in the oxidation of benzylamine with a high selectivity of the dibenzylimine product (∼94-98%) compared with that of CeO2 nanocubes (∼69-91%). The existence of a strong synergistic effect at the interface sites between the CeO2 and MnOx components is a key factor for outstanding catalytic efficiency of the MnOx/CeO2 heteronanostructures.

  20. Efficient plasma-enhanced method for layered LiNi1/3Co1/3Mn1/3O2 cathodes with sulfur atom-scale modification for superior-performance Li-ion batteries

    NASA Astrophysics Data System (ADS)

    Jiang, Qianqian; Chen, Ning; Liu, Dongdong; Wang, Shuangyin; Zhang, Han

    2016-05-01

    In order to improve the electrochemical performance of LiNi1/3Co1/3Mn1/3O2 as a lithium insertion positive electrode material, atom-scale modification was realized to obtain the layered oxysulfide LiNi1/3Co1/3Mn1/3O2-xSx using a novel plasma-enhanced doping strategy. The structure and electrochemical performance of LiNi1/3Co1/3Mn1/3O2-xSx are investigated systematically, which confirms that the S doping can make the structure stable and benefit the electrochemical performance. The phys-chemical characterizations indicate that oxygen atoms in the initial LiNi1/3Co1/3Mn1/3O2 have been partially replaced by S atoms. It should be pointed out that the atom-scale modification does not significantly alter the intrinsic structure of the cathode. Compared to the pristine material, the LiNi1/3Co1/3Mn1/3O2-xSx shows a superior performance with a higher capacity (200.4 mA h g-1) and a significantly improved cycling stability (maintaining 94.46% of its initial discharge capacity after 100 cycles). Moreover, it has an excellent rate performance especially at elevated performance, which is probably due to the faster Li+ transportation after S doping into the layered structure. All the results show that the atom-scale modification with sulfur atoms on LiNi1/3Co1/3Mn1/3O2, which significantly improved the electrochemical performance, offers a novel anionic doping strategy to realize the atom-scale modification of electrode materials to improve their electrochemical performance.In order to improve the electrochemical performance of LiNi1/3Co1/3Mn1/3O2 as a lithium insertion positive electrode material, atom-scale modification was realized to obtain the layered oxysulfide LiNi1/3Co1/3Mn1/3O2-xSx using a novel plasma-enhanced doping strategy. The structure and electrochemical performance of LiNi1/3Co1/3Mn1/3O2-xSx are investigated systematically, which confirms that the S doping can make the structure stable and benefit the electrochemical performance. The phys

  1. A novel 3D energetic MOF of high energy content: synthesis and superior explosive performance of a Pb(ii) compound with 5,5'-bistetrazole-1,1'-diolate.

    PubMed

    Shang, Yu; Jin, Bo; Peng, Rufang; Liu, Qiangqiang; Tan, Bisheng; Guo, Zhicheng; Zhao, Jun; Zhang, Qingchun

    2016-09-21

    The development of high-performance insensitive energetic materials is important because of the increasing demand for these materials in military and civilian applications. A novel 3D energetic metal-organic framework (MOF) of exceptionally high energy content, [Pb(BTO)(H2O)]n, was synthesized and structurally characterized by single crystal X-ray diffraction, featuring a three-dimensional parallelogram porous framework, where BTO represents 5,5'-bistetrazole-1,1'-diolate. The thermal stability and energetic properties were determined, exhibiting good thermostability (Td = 309.0 °C), excellent detonation pressure (P) of 53.06 GPa, a detonation velocity (D) of 9.204 km s(-1), and acceptable sensitivity to confirmed impact (IS = 7.5 J). Notably, the complex possesses unprecedented superior density than the reported energetic MOFs. The results highlight this new MOF as a potential energetic material.

  2. A novel 3D energetic MOF of high energy content: synthesis and superior explosive performance of a Pb(ii) compound with 5,5'-bistetrazole-1,1'-diolate.

    PubMed

    Shang, Yu; Jin, Bo; Peng, Rufang; Liu, Qiangqiang; Tan, Bisheng; Guo, Zhicheng; Zhao, Jun; Zhang, Qingchun

    2016-09-21

    The development of high-performance insensitive energetic materials is important because of the increasing demand for these materials in military and civilian applications. A novel 3D energetic metal-organic framework (MOF) of exceptionally high energy content, [Pb(BTO)(H2O)]n, was synthesized and structurally characterized by single crystal X-ray diffraction, featuring a three-dimensional parallelogram porous framework, where BTO represents 5,5'-bistetrazole-1,1'-diolate. The thermal stability and energetic properties were determined, exhibiting good thermostability (Td = 309.0 °C), excellent detonation pressure (P) of 53.06 GPa, a detonation velocity (D) of 9.204 km s(-1), and acceptable sensitivity to confirmed impact (IS = 7.5 J). Notably, the complex possesses unprecedented superior density than the reported energetic MOFs. The results highlight this new MOF as a potential energetic material. PMID:27518537

  3. Efficient plasma-enhanced method for layered LiNi1/3Co1/3Mn1/3O2 cathodes with sulfur atom-scale modification for superior-performance Li-ion batteries.

    PubMed

    Jiang, Qianqian; Chen, Ning; Liu, Dongdong; Wang, Shuangyin; Zhang, Han

    2016-06-01

    In order to improve the electrochemical performance of LiNi1/3Co1/3Mn1/3O2 as a lithium insertion positive electrode material, atom-scale modification was realized to obtain the layered oxysulfide LiNi1/3Co1/3Mn1/3O2-xSx using a novel plasma-enhanced doping strategy. The structure and electrochemical performance of LiNi1/3Co1/3Mn1/3O2-xSx are investigated systematically, which confirms that the S doping can make the structure stable and benefit the electrochemical performance. The phys-chemical characterizations indicate that oxygen atoms in the initial LiNi1/3Co1/3Mn1/3O2 have been partially replaced by S atoms. It should be pointed out that the atom-scale modification does not significantly alter the intrinsic structure of the cathode. Compared to the pristine material, the LiNi1/3Co1/3Mn1/3O2-xSx shows a superior performance with a higher capacity (200.4 mA h g(-1)) and a significantly improved cycling stability (maintaining 94.46% of its initial discharge capacity after 100 cycles). Moreover, it has an excellent rate performance especially at elevated performance, which is probably due to the faster Li(+) transportation after S doping into the layered structure. All the results show that the atom-scale modification with sulfur atoms on LiNi1/3Co1/3Mn1/3O2, which significantly improved the electrochemical performance, offers a novel anionic doping strategy to realize the atom-scale modification of electrode materials to improve their electrochemical performance.

  4. A Review. A Criterion-related Study of Three Sets of Rating Scales Used for Measuring and Evaluating the Instrumental Achievement of First and Second Year Clarinet Students.

    ERIC Educational Resources Information Center

    Radocy, Rudolf E.

    1987-01-01

    Reviews a study that examined the validity of different rating scales for measuring instrumental achievement with the clarinet. Rejects the contention that the new rating scales are superior to the Clarinet Performance Rating Scale. (BSR)

  5. Ag/g-C3N4 catalyst with superior catalytic performance for the degradation of dyes: a borohydride-generated superoxide radical approach

    NASA Astrophysics Data System (ADS)

    Fu, Yongsheng; Huang, Ting; Zhang, Lili; Zhu, Junwu; Wang, Xin

    2015-08-01

    dissolved oxygen in the presence of BH4- and the synergistic effect of Ag nanoparticles and g-C3N4. Electronic supplementary information (ESI) available: The typical experimental details for the color reaction between the ferrous irons (Fe2+) and nitric oxide (NO); MO photodegradation performances in the presence of Ag/g-C3N4 or Ag/g-C3N4/TiO2 nanocomposites; TEM image of the pure g-C3N4 catalyst; The remaining MO, MB and NDY-GL in solution after reaching the adsorption-desorption equilibrium in the dark for 60 min with stirring; Catalytic degradation of MB and NDY-GL over the Ag/g-C3N4-4 catalyst in the presence of BH4- in the dark and under visible light irradiation. See DOI: 10.1039/c5nr03260a

  6. Fifteen Years of Collaborative Innovation and Achievement: NASA Nebraska Space Grant Consortium 15-Year Program Performance and Results Report

    NASA Technical Reports Server (NTRS)

    Schaaf, Michaela M.; Bowen, Brent D.; Fink, Mary M.; Nickerson, Jocelyn S.; Avery, Shelly; Carstenson, Larry; Dugan, James; Farritor, Shane; Joyce, James; Rebrovich, Barb

    2003-01-01

    Condensing five years of significant work into a brief narrative fitting PPR requirements gave the affiliates of the Nebraska Space Grant a valuable chance for reflection. Achievements of Space Grant in Nebraska were judiciously chosen for this document that best illustrate the resultant synergism of this consortium, keeping in mind that these examples are only a representation of greater activity throughout the state. Following are highlights of many of the finer and personal achievements for Nebraska Space Grant. The Consortium welcomes inquiries to elaborate on any of these accomplishments.

  7. Student Achievement Gaps in High-Performing Schools: Differences as a Function of the Professional Staff as a Learning Community.

    ERIC Educational Resources Information Center

    Cowley, Kimberly S.; Meehan, Merrill L.

    This study investigated differences among professional staff members' commitment to continuous learning and improvement in high-performing schools differentiated by student academic performance and disaggregated by race and socioeconomic status. A total of 48 high-performing schools were identified by Kentucky Department of Education staff based…

  8. Faculty Sense of Academic Optimism and Its Relationship to Students' Achievement in Well Performing High Schools

    ERIC Educational Resources Information Center

    Cromartie, Michael Tyrone

    2013-01-01

    The aim of this study was to determine the organizational characteristics and behaviors that contribute to sustaining a culture of academic optimism as a mechanism of student achievement. While there is a developing research base identifying both the individual elements of academic optimism as well as the academic optimism construct itself as…

  9. Closing the Achievement Gap: A Summer School Program to Accelerate the Academic Performance of Economically Disadvantaged Students

    ERIC Educational Resources Information Center

    Gonzalez, Ramon Michael

    2013-01-01

    With the increasing disparity in educational outcomes among economically and racially different groups of students, summer school has received attention from school reformers as a means to close the achievement gap. Given the interest in this topic by educators, researchers, and policymakers, there is little research on the impact of summer school…

  10. Five Social Disadvantages That Depress Student Performance: Why Schools Alone Can't Close Achievement Gaps. Report

    ERIC Educational Resources Information Center

    Morsy, Leila; Rothstein, Richard

    2015-01-01

    That students' social and economic characteristics shape their cognitive and behavioral outcomes is well established, yet policymakers typically resist accepting that non-school disadvantages necessarily depress outcomes. Rather, they look to better schools and teachers to close achievement gaps, and consistently come up short. This report…

  11. What Educational Initiatives Contribute to Higher than Expected Achievement in Student Performance for Public Schools in the State of Indiana?

    ERIC Educational Resources Information Center

    Keeley, Thomas Allen

    2010-01-01

    The purpose of this study was to determine whether the areas of teaching methods, teacher-student relationships, school structure, school-community partnerships or school leadership were significantly embedded in practice and acted as a change agent among school systems that achieve higher than expected results on their state standardized testing…

  12. Predicting Performance on State Achievement Tests Using Curriculum-Based Measurement in Reading: A Multilevel Meta-Analysis

    ERIC Educational Resources Information Center

    Yeo, Seungsoo

    2010-01-01

    The purpose of this synthesis was to examine the relationship between Curriculum-Based Measurement (CBM) and statewide achievement tests in reading. A multilevel meta-analysis was used to calculate the correlation coefficient of the population for 27 studies that met the inclusion criteria. Results showed an overall large correlation coefficient…

  13. A Comparison of Stanford Achievement Test (SAT-9) Performance across Grade, Gender, Ethnicity, and Educational Program Placement.

    ERIC Educational Resources Information Center

    Sanchez, Kathryn; Kellow, Tom; Ye, Renmin

    This study compared Stanford Achievement Test (SAT-9) academic subtest scores by students' grade, gender, and ethnicity and across different educational programs (e.g., Title I and special education). The study sample consisted of 144,701 students from public schools in a large city in the Southwest United States (grades 1-11). Raw data were taken…

  14. The Relationship between Student Achievement of At-Risk Students and the Georgia Performance Standards in Mathematics

    ERIC Educational Resources Information Center

    Hill, Loralee Ann

    2012-01-01

    Educational leaders continue to be challenged in terms of accountability measures for increased student achievement, as mandated by the No Child Left Behind Act of 2001 (NCLB). In particular, schools must show adequate yearly progress (AYP) reaching 100% proficiency levels for all students in the areas of English language arts and mathematics by…

  15. Staying with the Text: The Contribution of Gender, Achievement Orientations, and Interest to Students' Performance on a Literacy Task

    ERIC Educational Resources Information Center

    Graham, Jedda; Tisher, Ruth; Ainley, Mary; Kennedy, Gregor

    2008-01-01

    This study addresses concerns about boys' underperformance on literacy tasks compared to girls, by investigating male and females students' responses to narrative texts. Participants were 142 Grade 9 and 10 students. Achievement orientations, including goals, self-efficacy, and self-handicapping, were measured and approach and avoidance factors…

  16. The Effects of Socioeconomic Strata, Sex and Reading Achievement Level on the Auditory-Visual Integration Performance of Sixth Graders.

    ERIC Educational Resources Information Center

    King, Michael Duane

    This study investigates the differences between the auditory-visual integration ability of 80 sixth grade students when such variables as socioeconomic status, sex, intelligence, conservation ability, and reading achievement were controlled. Socioeconomic Strata were determined by Hollingshead's Four Factor Index of Social Position. The California…

  17. Comparing the Reading Performance of High-Achieving Adolescents: Computer-Based Testing versus Paper/Pencil

    ERIC Educational Resources Information Center

    Eno, Linda Peet

    2011-01-01

    Literacy is moving into the digital context. Many of the literacy tasks associated with higher education, the workplace, and civic life now take place in the digital world. Literacy in high school, however, languishes in the text world. This study compared the text literacy of a group of high-achieving 10th-grade students, to their digital…

  18. The Impact of AP® Achievement Institute I on Students' AP Performance. Research Report No. 2012-7

    ERIC Educational Resources Information Center

    Bausmith, Jennifer Merriman; Laitusis, Vytas

    2012-01-01

    The AP Achievement Institute I (APAI I) is a four-day professional development program offered to teachers and administrators by EXCELerator™, a district reform program operated by the College Board. The APAI I program is designed to help teachers develop effective AP instructional strategies for a diverse student body and to help district,…

  19. The Effect of Performance-Pay in Little Rock, Arkansas on Student Achievement. Working Paper 2008-02

    ERIC Educational Resources Information Center

    Winters, Marcus; Greene, Jay P.; Ritter, Gary; Marsh, Ryan

    2008-01-01

    This paper examines evidence from a performance-pay program implemented in five Little Rock, Arkansas elementary schools between 2004 and 2007. Using a differences-in-differences approach, the evidence shows that students whose teachers were eligible for performance pay made substantially larger test score gains in math, reading, and language than…

  20. Making Performance Accountability Work: English Lessons for U.S. Community Colleges: An Achieving the Dream Policy Brief

    ERIC Educational Resources Information Center

    Jaquette, Ozan

    2006-01-01

    Most states have experimented with performance accountability as a way to drive improvement in public higher education institutions and systems. However, efforts to implement performance funding in the United States have yielded mixed results. This policy brief describes the reforms that dramatically changed the policy landscape in England and…

  1. The effect of retesting on end-of-semester performance in high school chemistry at three levels of previous science achievement

    NASA Astrophysics Data System (ADS)

    Deboer, George E.

    To determine the effect of retesting on student learning in chemistry, three questions were addressed by means of a 3 × 2 (achievement level X treatment) factorial design: (1) Does retesting affect differently the end-of-semester mastery of course objectives of students who are grouped according to their previous achievement in science? (2) Do students who are given an opportunity to take retests merely delay their studying and perform at a lower level on initial tests than nonretested students? (3) Is the procrastination of retested students (if it exists) affected by their achievement level? The results showed that for one of four units low ability students who were retested demonstrated greater learning gains than low ability students who were not retested, and that procrastination, if it was present, did not have significant effects on student learning at any achievement level. Results were discussed in terms of the students' room for improvement, motivation to improve, and ability to improve.

  2. Long-term costs of inflated self-estimate on academic performance among adolescent students: a case of second-language achievements.

    PubMed

    Yang, Mu-Li; Chuang, Hsueh-Hua; Chiou, Wen-Bin

    2009-12-01

    Past studies suggest that the adaptive or maladaptive consequences of inflated self-estimate, one form of positive illusions, require further investigation. 308 freshmen at a junior college (164 women, 144 men; M age = 19.8 yr., SD = 1.1) participated in a longitudinal study during a 2-yr. period. There were three assessments of short- and long-term effects of overly positive self-estimates on second-language achievement. Students' overestimation of subsequent performance appears to be associated with lower achievement. Those students with apparently inflated self-estimates performed marginally better on the first assessment but worse in the second and final assessments. Students with more accurate self-estimates showed improvement on all assessments. The findings suggested that overinflated self-estimates, i.e., positive illusions, among adolescent students might lead to a lower achievement over the long-term.

  3. The Relationship between Students' Performance on the Cognitive Abilities Test (CogAT) and the Fourth and Fifth Grade Reading and Math Achievement Tests in Ohio

    ERIC Educational Resources Information Center

    Warnimont, Chad S.

    2010-01-01

    The purpose of this quantitative study was to examine the relationship between students' performance on the Cognitive Abilities Test (CogAT) and the fourth and fifth grade Reading and Math Achievement Tests in Ohio. The sample utilized students from a suburban school district in Northwest Ohio. Third grade CogAT scores (2006-2007 school year), 4th…

  4. Beating the Odds: A City-by-City Analysis of Student Performance and Achievement Gaps on State Assessments. Results from the 2003-2004 School Year

    ERIC Educational Resources Information Center

    Casserly, Michael

    2005-01-01

    The Council of the Great City Schools has prepared this fifth edition of "Beating the Odds" ("Beating the Odds V)" to give the nation another look at how inner-city schools are performing on the academic goals and standards set by the states for our children. This analysis examines student achievement in math and reading through spring 2004. It…

  5. How Does the Science Writing Heuristic Approach Affect Students' Performances of Different Academic Achievement Levels? A Case for High School Chemistry

    ERIC Educational Resources Information Center

    Kingir, Sevgi; Geban, Omer; Gunel, Murat

    2012-01-01

    This study investigates the effects of the Science Writing Heuristic (SWH), known as an argumentation-based science inquiry approach, on Grade 9 students' performance on a post-test in relation to their academic achievement levels. Four intact classes taught by 2 chemistry teachers from a Turkish public high school were selected for the study; one…

  6. The Impact of a State Takeover on Academic Achievement, School Performance, and School Leadership in a Rural South Carolina School District

    ERIC Educational Resources Information Center

    Bishop, Janice Zissette

    2009-01-01

    This case study on the impact of a state takeover in one of South Carolina's most rural school districts ("referred to as the County School District") was completed using a quasi-experimental mixed methods design to examine the impact on academic achievement, school performance, and school leadership as a result of the South Carolina Department of…

  7. A Comparative Case Study of Factors Distinguishing between High and Low-Performance on Reading Achievement in Elementary Rural Appalachian Schools

    ERIC Educational Resources Information Center

    Chambers, Jennifer; Hausman, Charles

    2014-01-01

    This qualitative comparative case study identified factors that distinguish between high and low-performance on reading achievement in elementary rural Appalachian schools. This study determined the most effective instructional reading strategies, as well as other influential factors, implemented by school districts in the rural Appalachia area…

  8. A Comparative Case Study of Factors Distinguishing between High and Low-Performance on Reading Achievement in Elementary Rural Appalachian Schools

    ERIC Educational Resources Information Center

    Chambers, Jennifer R.

    2012-01-01

    This qualitative comparative case study identified factors that distinguish between high and low-performance on reading achievement in elementary rural Appalachian schools. This study determined the most effective instructional reading strategies, as well as other influential factors, implemented by school districts in the rural Appalachia area…

  9. The Effect of Performance Assessment-Driven Instruction on the Attitude and Achievement of Senior High School Students in Mathematics in Cape Coast Metropolis, Ghana

    ERIC Educational Resources Information Center

    Arhin, Ato Kwamina

    2015-01-01

    The study was a quasi-experimental research project conducted to investigate the effect of performance assessment-driven instructions on the attitude and achievement in mathematics of senior high school students in Ghana at Ghana National College in Cape Coast. Two Form 1 science classes were used for the study and were assigned as experimental…

  10. Building trust through promises and performance. Can your organization achieve the stellar results and employee loyalty found at Southwest Airlines?

    PubMed

    O'Connor, Edward J; Annison, Michael H

    2002-01-01

    Establishing a trusting relationship with your employees can help you transform your organization into a top performer. Examine how well-defined visions and goals are some of the keys to building that trust. PMID:11806234

  11. Understanding the Low Mathematics Achievement of Chilean Students: A Cross-National Analysis Using TIMSS Data

    ERIC Educational Resources Information Center

    Ramirez, Maria Jose

    2004-01-01

    The low performance of Chile in the TIMSS 1999 international study of mathematics and science achievement was a great disappointment. To investigate the likely causes for low performance in mathematics, this study 1) compared Chile to three countries and one large school system that had comparable economic conditions but superior mathematics…

  12. Superior Na-Storage Performance of Low-Temperature-Synthesized Na3(VO(1-x)PO4)2F(1+2x) (0≤x≤1) Nanoparticles for Na-Ion Batteries.

    PubMed

    Qi, Yuruo; Mu, Linqin; Zhao, Junmei; Hu, Yong-Sheng; Liu, Huizhou; Dai, Sheng

    2015-08-17

    Na-ion batteries are becoming comparable to Li-ion batteries because of their similar chemical characteristics and abundant sources of sodium. However, the materials production should be cost-effective in order to meet the demand for large-scale application. Here, a series of nanosized high-performance cathode materials, Na3(VO(1-x)PO4)2F(1+2x) (0≤x≤1), has been synthesized by a solvothermal low-temperature (60-120 °C) strategy without the use of organic ligands or surfactants. The as-synthesized Na3(VOPO4)2F nanoparticles show the best Na-storage performance reported so far in terms of both high rate capability (up to 10 C rate) and long cycle stability over 1200 cycles. To the best of our knowledge, the current developed synthetic strategy for Na3(VO(1-x)PO4)2F(1+2x) is by far one of the least expensive and energy-consuming methods, much superior to the conventional high-temperature solid-state method.

  13. Fifteen Years of Collaborative Innovation and Achievement: NASA Nebraska Space Grant Consortium 15-Year Program Performance and Results Report

    NASA Technical Reports Server (NTRS)

    Schaaf, Michaela M. (Editor); Bowen, Brent D.; Fink, Mary M.; Nickerson, Jocelyn S.; Avery Shelly; Calamaio, Caprice; Carstenson, Larry; Dugan, James; Farr, Lynne; Farritor, Shane

    2003-01-01

    This 15-year evaluation serves as a summary document highlighting the numerous and complete successes of the Nebraska Space Grant Program. Innovation has been highlighted through significant new endeavors during this 5-year period, such as placement of students and faculty at NASA Centers and the expansion of NSGC Native American Outreach Programs. While the last national program evaluation resulted in Nebraska s ranking as the top Capability Enhancement Consortium, and 5th best overall, Nebraska felt there was room for significant growth and development. This has been validated through the recent competitive attainment of Designated Grant status and has allowed for the exploration of new initiatives, as well as the expansion of already successful programs. A comprehensive strategic planning effort has involved all Nebraska representative entities and has guided Nebraska Space Grant through the evaluation period, providing a basis for continual advancement. Nebraska rigorously employs evaluation techniques to ensure that stated outcomes and metrics are achieved and that weaknesses are identified and corrected. With this coordinated approach, Nebraska expects that the next 5 years will yield new opportunities for significant achievement. Nebraska Space Grant will embrace new national endeavors, including the integration of Pender Public Schools -Nebraska s NASA Explorer School, geospatial initiatives, and the National Student Satellite Program.

  14. Employing low-temperature barriers to achieve strain-relaxed and high-performance GaN-based LEDs.

    PubMed

    Lin, Zhiting; Wang, Haiyan; Wang, Wenliang; Lin, Yunhao; Yang, Meijuan; Chen, Shuqi; Li, Guoqiang

    2016-05-30

    The epitaxial structure design of low-temperature barriers has been adopted to promote strain relaxation in multiple quantum well (MQWs) and achieve high-efficient GaN-based light-emitting diodes (LEDs). With these barriers, the relaxation value of wells increases from 0 to 4.59%. The strain-relaxed mechanism of low-temperature barriers is also discussed. The LED chip with the barriers grown at the TMIn flow of 75 sccm and the growth temperature of 830 °C has an optimal strain relaxation value of 1.53% in wells, and exhibits the largest light output power of 63.83 mW at the injection current of 65 mA, which is higher than that of conventional LED (51.89 mW) by 23%. In-depth studies reveal that the optimal low-temperature barriers remarkably promote the strain relaxation in wells without forming large density of crystalline defects. This achievement of high-efficiency LEDs sheds light on the future solid-state lighting applications. PMID:27410111

  15. Final LDRD report : science-based solutions to achieve high-performance deep-UV laser diodes.

    SciTech Connect

    Armstrong, Andrew M.; Miller, Mary A.; Crawford, Mary Hagerott; Alessi, Leonard J.; Smith, Michael L.; Henry, Tanya A.; Westlake, Karl R.; Cross, Karen Charlene; Allerman, Andrew Alan; Lee, Stephen Roger

    2011-12-01

    We present the results of a three year LDRD project that has focused on overcoming major materials roadblocks to achieving AlGaN-based deep-UV laser diodes. We describe our growth approach to achieving AlGaN templates with greater than ten times reduction of threading dislocations which resulted in greater than seven times enhancement of AlGaN quantum well photoluminescence and 15 times increase in electroluminescence from LED test structures. We describe the application of deep-level optical spectroscopy to AlGaN epilayers to quantify deep level energies and densities and further correlate defect properties with AlGaN luminescence efficiency. We further review our development of p-type short period superlattice structures as an approach to mitigate the high acceptor activation energies in AlGaN alloys. Finally, we describe our laser diode fabrication process, highlighting the development of highly vertical and smooth etched laser facets, as well as characterization of resulting laser heterostructures.

  16. Both Patient and Facility Contribute to Achieving the Centers for Medicare and Medicaid Services' Pay-for-Performance Target for Dialysis Adequacy

    PubMed Central

    Tighiouart, Hocine; Meyer, Klemens B.; Miskulin, Dana C.

    2011-01-01

    The Centers for Medicare and Medicaid Services (CMS) designated the achieved urea reduction ratio (URR) as a pay-for-performance measure, but to what extent this measure reflects patient characteristics and adherence instead of its intent to reflect facility performance is unknown. Here, we quantified the contributions of patient case-mix and adherence to the variability in achieving URR targets across dialysis facilities. We found that 92% of 10,069 hemodialysis patients treated at 173 facilities during the last quarter of 2004 achieved the target URR ≥65%. Mixed-effect models with random intercept for dialysis facility revealed a significant facility effect: 11.5% of the variation in achievement of target URR was attributable to the facility level. Adjusting for patient case-mix reduced the proportion of variation attributable to the facility level to 6.7%. Patient gender, body surface area, dialysis access, and adherence with treatment strongly associated with achievement of the URR target. We could not identify specific facility characteristics that explained the remaining variation between facilities. These data suggest that if adherence is not a modifiable patient characteristic, providers could be unfairly penalized for caring for these patients under current CMS policy. These penalties may have unintended consequences. PMID:22025629

  17. Both patient and facility contribute to achieving the Centers for Medicare and Medicaid Services' pay-for-performance target for dialysis adequacy.

    PubMed

    Tangri, Navdeep; Tighiouart, Hocine; Meyer, Klemens B; Miskulin, Dana C

    2011-12-01

    The Centers for Medicare and Medicaid Services (CMS) designated the achieved urea reduction ratio (URR) as a pay-for-performance measure, but to what extent this measure reflects patient characteristics and adherence instead of its intent to reflect facility performance is unknown. Here, we quantified the contributions of patient case-mix and adherence to the variability in achieving URR targets across dialysis facilities. We found that 92% of 10,069 hemodialysis patients treated at 173 facilities during the last quarter of 2004 achieved the target URR ≥65%. Mixed-effect models with random intercept for dialysis facility revealed a significant facility effect: 11.5% of the variation in achievement of target URR was attributable to the facility level. Adjusting for patient case-mix reduced the proportion of variation attributable to the facility level to 6.7%. Patient gender, body surface area, dialysis access, and adherence with treatment strongly associated with achievement of the URR target. We could not identify specific facility characteristics that explained the remaining variation between facilities. These data suggest that if adherence is not a modifiable patient characteristic, providers could be unfairly penalized for caring for these patients under current CMS policy. These penalties may have unintended consequences.

  18. How can we achieve and maintain high-quality performance of health workers in low-resource settings?

    PubMed

    Rowe, Alexander K; de Savigny, Don; Lanata, Claudio F; Victora, Cesar G

    In low and middle income countries, health workers are essential for the delivery of health interventions. However, inadequate health-worker performance is a very widespread problem. We present an overview of issues and evidence about the determinants of performance and strategies for improving it. Health-worker practices are complex behaviours that have many potential influences. Reviews of intervention studies in low and middle income countries suggest that the simple dissemination of written guidelines is often ineffective, that supervision and audit with feedback is generally effective, and that multifaceted interventions might be more effective than single interventions. Few interventions have been evaluated with rigorous cost-effectiveness trials, and such studies are urgently needed to guide policy. We propose an international collaborative research agenda to generate knowledge about the true determinants of performance and about the effectiveness of strategies to improve performance. Furthermore, we recommend that ministries of health and international organisations should actively help translate research findings into action to improve health-worker performance, and thereby improve health.

  19. Optimizing Performance on Linux Clusters Using Advanced Communication Protocols: Achieving Over 10 Teraflops on a 8.6 Teraflops Linpack-Rated Linux Cluster

    SciTech Connect

    Krishnan, Manoj Kumar; Nieplocha, Jarek

    2005-04-26

    Advancements in high-performance networks (Quadrics, Infiniband or Myrinet) continue to improve the efficiency of modern clusters. However, the average application efficiency is as small fraction of the peak as the system’s efficiency. This paper describes techniques for optimizing application performance on Linux clusters using Remote Memory Access communication protocols. The effectiveness of these optimizations is presented in the context of an application kernel, dense matrix multiplication. The result was achieving over 10 teraflops on HP Linux cluster on which LINPACK performance is measured as 8.6 teraflops.

  20. 50% duty cycle may be inappropriate to achieve a sufficient chest compression depth when cardiopulmonary resuscitation is performed by female or light rescuers

    PubMed Central

    Lee, Chang Jae; Chung, Tae Nyoung; Bae, Jinkun; Kim, Eui Chung; Choi, Sung Wook; Kim, Ok Jun

    2015-01-01

    Objective Current guidelines for cardiopulmonary resuscitation recommend chest compressions (CC) during 50% of the duty cycle (DC) in part because of the ease with which individuals may learn to achieve it with practice. However, no consideration has been given to a possible interaction between DC and depth of CC, which has been the subject of recent study. Our aim was to determine if 50% DC is inappropriate to achieve sufficient chest compression depth for female and light rescuers. Methods Previously collected CC data, performed by senior medical students guided by metronome sounds with various down-stroke patterns and rates, were included in the analysis. Multiple linear regression analysis was performed to determine the association between average compression depth (ACD) with average compression rate (ACR), DC, and physical characteristics of the performers. Expected ACD was calculated for various settings. Results DC, ACR, body weight, male sex, and self-assessed physical strength were significantly associated with ACD in multivariate analysis. Based on our calculations, with 50% of DC, only men with ACR of 140/min or faster or body weight over 74 kg with ACR of 120/min can achieve sufficient ACD. Conclusion A shorter DC is independently correlated with deeper CC during simulated cardiopulmonary resuscitation. The optimal DC recommended in current guidelines may be inappropriate for achieving sufficient CD, especially for female or lighter-weight rescuers.

  1. Supervised, Multivariate, Whole-Brain Reduction Did Not Help to Achieve High Classification Performance in Schizophrenia Research.

    PubMed

    Janousova, Eva; Montana, Giovanni; Kasparek, Tomas; Schwarz, Daniel

    2016-01-01

    We examined how penalized linear discriminant analysis with resampling, which is a supervised, multivariate, whole-brain reduction technique, can help schizophrenia diagnostics and research. In an experiment with magnetic resonance brain images of 52 first-episode schizophrenia patients and 52 healthy controls, this method allowed us to select brain areas relevant to schizophrenia, such as the left prefrontal cortex, the anterior cingulum, the right anterior insula, the thalamus, and the hippocampus. Nevertheless, the classification performance based on such reduced data was not significantly better than the classification of data reduced by mass univariate selection using a t-test or unsupervised multivariate reduction using principal component analysis. Moreover, we found no important influence of the type of imaging features, namely local deformations or gray matter volumes, and the classification method, specifically linear discriminant analysis or linear support vector machines, on the classification results. However, we ascertained significant effect of a cross-validation setting on classification performance as classification results were overestimated even though the resampling was performed during the selection of brain imaging features. Therefore, it is critically important to perform cross-validation in all steps of the analysis (not only during classification) in case there is no external validation set to avoid optimistically biasing the results of classification studies. PMID:27610072

  2. Technology for monitoring shot-level light source performance data to achieve high-optimization of lithography processes

    NASA Astrophysics Data System (ADS)

    Moriya, Masato; Ochiai, Hideyuki; Watabe, Yoshinobu; Ishida, Keisuke; Masuda, Hiroyuki; Sasaki, Youichi; Kumazaki, Takahito; Kurosu, Akihiko; Ohta, Takeshi; Kakizaki, Kouji; Matsunaga, Takashi; Mizoguchi, Hakaru

    2014-03-01

    Gigaphoton has developed a new monitoring system that provides shot-level light source performance data to FDC systems during exposure time. The system provides basic monitoring data (e.g. Energy, Wavelength, Bandwidth, etc.) and beam performance data, such as Beam Profile, Pointing, Divergence, Polarization can also be monitored using a new metrology tool called the Beam Performance Monitor (BPM) module. During exposure time the system automatically identifies the start and end timing of the wafer and each shot based on the burst of firing signals from the scanner, and stores the measured data in sequence. The stored data is sorted by wafer or by shot, and sent to REDeeM Piece which in turn converts the data to the user's protocol and send it to the FDC system. The user also has the option to directly view or download the stored data using a GUI. Through this monitoring system, users can manage light sources data at the shot or reticle level to facilitate optimization of performance and running cost of the light source for each process. This monitoring system can be easily retrofitted to Gigaphoton's current ArF laser light sources. The beam splitter of the BPM was specially designed to bend only a small fraction of the source beam, so we are able to simply install the BPM without the need for special optical alignment.

  3. A Descriptive-Comparative Study of Teacher Performance Evaluation on Student Achievement in a Public School District

    ERIC Educational Resources Information Center

    Christensen, William Howard

    2013-01-01

    In 2010, the federal government increased accountability expectations by placing more emphasis on monitoring teacher performance. Using a model that focuses on the New York State teacher evaluation system, that is comprised of a rubric for observation, local student assessment scores, and student state assessment scores, this…

  4. Supervised, Multivariate, Whole-Brain Reduction Did Not Help to Achieve High Classification Performance in Schizophrenia Research

    PubMed Central

    Janousova, Eva; Montana, Giovanni; Kasparek, Tomas; Schwarz, Daniel

    2016-01-01

    We examined how penalized linear discriminant analysis with resampling, which is a supervised, multivariate, whole-brain reduction technique, can help schizophrenia diagnostics and research. In an experiment with magnetic resonance brain images of 52 first-episode schizophrenia patients and 52 healthy controls, this method allowed us to select brain areas relevant to schizophrenia, such as the left prefrontal cortex, the anterior cingulum, the right anterior insula, the thalamus, and the hippocampus. Nevertheless, the classification performance based on such reduced data was not significantly better than the classification of data reduced by mass univariate selection using a t-test or unsupervised multivariate reduction using principal component analysis. Moreover, we found no important influence of the type of imaging features, namely local deformations or gray matter volumes, and the classification method, specifically linear discriminant analysis or linear support vector machines, on the classification results. However, we ascertained significant effect of a cross-validation setting on classification performance as classification results were overestimated even though the resampling was performed during the selection of brain imaging features. Therefore, it is critically important to perform cross-validation in all steps of the analysis (not only during classification) in case there is no external validation set to avoid optimistically biasing the results of classification studies. PMID:27610072

  5. Failure Is Not an Option (TM). Six Principles That Guide Student Achievement in High-Performing Schools

    ERIC Educational Resources Information Center

    Blankstein, Alan M.

    2004-01-01

    The author builds upon a foundation which identifies courageous school leadership and the professional learning community as the center of effective school reform. The author offers six guiding principles steps for creating and sustaining a high-performing school: (1) Common mission, vision, values, and goals: (2) Systems for prevention and…

  6. The Influence of Parenting Styles, Achievement Motivation, and Self-Efficacy on Academic Performance in College Students

    ERIC Educational Resources Information Center

    Turner, Erlanger A.; Chandler, Megan; Heffer, Robert W.

    2009-01-01

    Parenting styles have consistently been shown to relate to various outcomes such as youth psychopathology, behavior problems, and academic performance. Building on the research in the parenting style literature, along with examining components of self-determination theory, the present study examined the relations among authoritative parenting…

  7. Supervised, Multivariate, Whole-Brain Reduction Did Not Help to Achieve High Classification Performance in Schizophrenia Research

    PubMed Central

    Janousova, Eva; Montana, Giovanni; Kasparek, Tomas; Schwarz, Daniel

    2016-01-01

    We examined how penalized linear discriminant analysis with resampling, which is a supervised, multivariate, whole-brain reduction technique, can help schizophrenia diagnostics and research. In an experiment with magnetic resonance brain images of 52 first-episode schizophrenia patients and 52 healthy controls, this method allowed us to select brain areas relevant to schizophrenia, such as the left prefrontal cortex, the anterior cingulum, the right anterior insula, the thalamus, and the hippocampus. Nevertheless, the classification performance based on such reduced data was not significantly better than the classification of data reduced by mass univariate selection using a t-test or unsupervised multivariate reduction using principal component analysis. Moreover, we found no important influence of the type of imaging features, namely local deformations or gray matter volumes, and the classification method, specifically linear discriminant analysis or linear support vector machines, on the classification results. However, we ascertained significant effect of a cross-validation setting on classification performance as classification results were overestimated even though the resampling was performed during the selection of brain imaging features. Therefore, it is critically important to perform cross-validation in all steps of the analysis (not only during classification) in case there is no external validation set to avoid optimistically biasing the results of classification studies.

  8. Substantial Improvements in Performance Indicators Achieved in a Peripheral Blood Mononuclear Cell Cryopreservation Quality Assurance Program Using Single Donor Samples▿

    PubMed Central

    Dyer, Wayne B.; Pett, Sarah L.; Sullivan, John S.; Emery, Sean; Cooper, David A.; Kelleher, Anthony D.; Lloyd, Andrew; Lewin, Sharon R.

    2007-01-01

    Storage of high-quality cryopreserved peripheral blood mononuclear cells (PBMC) is often a requirement for multicenter clinical trials and requires a reproducibly high standard of practice. A quality assurance program (QAP) was established to assess an Australia-wide network of laboratories in the provision of high-quality PBMC (determined by yield, viability, and function), using blood taken from single donors (human immunodeficiency virus [HIV] positive and HIV negative) and shipped to each site for preparation and cryopreservation of PBMC. The aim of the QAP was to provide laboratory accreditation for participation in clinical trials and cohort studies which require preparation and cryopreservation of PBMC and to assist all laboratories to prepare PBMC with a viability of >80% and yield of >50% following thawing. Many laboratories failed to reach this standard on the initial QAP round. Interventions to improve performance included telephone interviews with the staff at each laboratory, two annual wet workshops, and direct access to a senior scientist to discuss performance following each QAP round. Performance improved substantially in the majority of sites that initially failed the QAP (P = 0.002 and P = 0.001 for viability and yield, respectively). In a minority of laboratories, there was no improvement (n = 2), while a high standard was retained at the laboratories that commenced with adequate performance (n = 3). These findings demonstrate that simple interventions and monitoring of PBMC preparation and cryopreservation from multiple laboratories can significantly improve performance and contribute to maintenance of a network of laboratories accredited for quality PBMC fractionation and cryopreservation. PMID:17050740

  9. Enhanced in Vitro and in Vivo Performance of Mg-Zn-Y-Nd Alloy Achieved with APTES Pretreatment for Drug-Eluting Vascular Stent Application.

    PubMed

    Liu, Jing; Zheng, Bo; Wang, Pei; Wang, Xingang; Zhang, Bin; Shi, Qiuping; Xi, Tingfei; Chen, Ming; Guan, Shaokang

    2016-07-20

    Bioabsorbable magnesium alloys are becoming prominent as temporary functional implants, as they avoid the risks generated by permanent metallic implants such as persistent inflammation and late restenosis. Nevertheless, the overfast corrosion of Mg alloys under physiological conditions hinders their wider application as medical implant materials. Here we investigate a simple one-step process to introduce a cross-linked 3-amino-propyltrimethoxysilane (APTES) silane physical barrier layer on the surface of Mg-Zn-Y-Nd alloys prior to electrostatic spraying with rapamycin-eluting poly(lactic-co-glycolic acid) (PLGA) layer. Surface microstructure was characterized by scanning electron microscope and Fourier transform infrared spectroscopy. Nanoscratch test verified the superior adhesion strength of PLGA coating in the group pretreated with APTES. Electrochemical tests combined with long-term immersion results suggested that the preferable in vitro anticorrosion behavior could be achieved by dense APTES barrier. Cell morphology and proliferation data demonstrated that APTES pretreated group resulted in remarkably preferable compatibility for both human umbilical vein endothelial cells and vascular smooth muscle cells. On the basis of excellent in vitro mechenical property, the animal study on the APTES pretreated Mg-Zn-Y-Nd stent implanted into porcine coronary arteries confirmed benign tissue compatibility as well as re-endothelialization without thrombogenesis or in-stent restenosis at six-month followup. PMID:27331417

  10. Inverse modeling of surface-water discharge to achieve restoration salinity performance measures in Florida Bay, Florida

    USGS Publications Warehouse

    Swain, E.D.; James, D.E.

    2008-01-01

    The use of numerical modeling to evaluate regional water-management practices involves the simulation of various alternative water-delivery scenarios, which typically are designed intuitively rather than analytically. These scenario simulations are used to analyze how specific water-management practices affect factors such as water levels, flows, and salinities. In lieu of testing a variety of scenario simulations in a trial-and-error manner, an optimization technique may be used to more precisely and directly define good water-management alternatives. A numerical model application in the coastal regions of Florida Bay and Everglades National Park (ENP), representing the surface- and ground-water hydrology for the region, is a good example of a tool used to evaluate restoration scenarios. The Southern Inland and Coastal System (SICS) model simulates this area with a two-dimensional hydrodynamic surface-water model and a three-dimensional ground-water model, linked to represent the interaction of the two systems with salinity transport. This coastal wetland environment is of great interest in restoration efforts, and the SICS model is used to analyze the effects of alternative water-management scenarios. The SICS model is run within an inverse modeling program called UCODE. In this application, UCODE adjusts the regulated inflows to ENP while SICS is run iteratively. UCODE creates parameters that define inflow within an allowable range for the SICS model based on SICS model output statistics, with the objective of matching user-defined target salinities that meet ecosystem restoration criteria. Preliminary results obtained using two different parameterization methods illustrate the ability of the model to achieve the goals of adjusting the range and reducing the variance of salinity values in the target area. The salinity variance in the primary zone of interest was reduced from an original value of 0.509 psu2 to values 0.418 psu2 and 0.342 psu2 using different

  11. Some Suggested Techniques for Achieving Required Main Ring Low Level RF Performance for the Tevatron I Program

    SciTech Connect

    Griffin, J.E.; MacLachlan, J.

    1984-05-01

    These techniques are derived from experience with the existing low level rf system and from the results of accelerator experiments directed at the Tev I requirements which were performed using a specially modified low level rf system. The techniques suggested here are not necessarily unique and other techniques may be acceptable. It is important to realize that certain performance requirements on the Booster and Main Ring are substantially different in the Tev I program from those which have been acceptable in the fixed target program. For example, the longitudinal emittance of the bunches has been routinely and intentionally blown up by the 'bunch spreader' during acceleration to improve the smoothness of the spill. In the Tev I case, the 'bunch narrowing' procedure preceding {bar p} production and in bunch coalescing is facilitated by maintaining the smallest possible longitudinal emittance (i.e. the largest possible longitudinal phase space density). Also, during fixed target physics the Main Ring is essentially full (i.e. approx. 1090 of 1113 buckets occupied) so transient beam loading of the rf system is negligible except during injection, whereas for {bar p} production a single high intensity Booster batch (approx. 83 bunches) is to be accelerated causing substantial transient beam induced phase shift of the rf voltage during each passage. The low level phase and position error signals are normally derived from an essentially full ring during fixed target operation whereas in the Tev I program the systems must perform adequately with as few as ten adjacent buckets occupied. Because of the differences in emphasis between fixed target operation and Tevatron I operation is seems sensible to use separate low level rf systems for these two modes of operation. If a single low level system were to be used for both modes of operation some compromises may be necessary which might cause performance in either mode to be less than adequate. Because of the severe demands

  12. Effects of heat exposure and 3% dehydration achieved via hot water immersion on repeated cycle sprint performance.

    PubMed

    Kraft, Justin A; Green, James M; Bishop, Phillip A; Richardson, Mark T; Neggers, Yasmin H; Leeper, James D

    2011-03-01

    This study examined effects of heat exposure with and without dehydration on repeated anaerobic cycling. Males (n = 10) completed 3 trials: control (CT), water-bath heat exposure (∼39°C) to 3% dehydration (with fluid replacement) (HE), and similar heat exposure to 3% dehydration (DEHY). Hematocrit increased significantly from pre to postheat immersion in both HE and DEHY. Participants performed 6 × 15s cycle sprints (30s active recovery). Mean Power (MP) was significantly lower vs. CT (596 ± 66 W) for DEHY (569 ± 72 W), and the difference approached significance for HE (582 ± 76 W, p = 0.07). Peak Power (PP) was significantly lower vs. CT (900 ± 117 W) for HE (870 ± 128 W) and approached significance for DEHY (857 ± 145 W, p = 0.07). Postsprint ratings of perceived exertion was higher during DEHY (6.4 ± 2.0) and HE (6.3 ± 1.6) than CT (5.7 ± 2.1). Combined heat and dehydration impaired MP and PP (decrements greatest in later bouts) with HE performance intermediate to CT and DEHY.

  13. Control-value theory: using achievement emotions to improve understanding of motivation, learning, and performance in medical education: AMEE Guide No. 64.

    PubMed

    Artino, Anthony R; Holmboe, Eric S; Durning, Steven J

    2012-01-01

    In this AMEE Guide, we consider the emergent theoretical and empirical work on human emotion and how this work can inform the theory, research, and practice of medical education. In the Guide, we define emotion, in general, and achievement emotions, more specifically. We describe one of the leading contemporary theories of achievement emotions, control-value theory (Pekrun 2006), and we distinguish between different types of achievement emotions, their proximal antecedents, and their consequences for motivation, learning, and performance. Next, we review the empirical support for control-value theory from non-medical fields and suggest several important implications for educational practice. In this section, we highlight the importance of designing learning environments that foster a high degree of control and value for students. Finally, we end with a discussion of the need for more research on achievement emotions in medical education, and we propose several key research questions we believe will facilitate our understanding of achievement emotions and their impact on important educational outcomes.

  14. The Development and Testing of Laboratory Performance Tasks for the Assessment of Achievement in High School Physics.

    NASA Astrophysics Data System (ADS)

    Boorman, Joan Marie

    The quest to stem "the rising tide of mediocrity" described in A Nation at Risk has prompted a myriad of changes in secondary science instruction. Appropriate assessments of these changes in curriculum are crucial to a meaningful evaluation of their effectiveness. Because the nature of many of the improvements has been to engage students in higher order thinking skills, simple paper and pencil tests are often inconclusive evaluation measures. Research has shown a more definitive assessment of a student's ability to apply higher order thinking skills is possible with tests of performance in problem-solving tasks in a science laboratory. The Physics Laboratory Skills Test (PLST) was developed as a prototype assessment instrument for evaluation of student ability to perform a range of process skills in the high school physics laboratory setting. The PLST included seven different items based on topics presented in a typical high school physics course. Each item constituted a separate laboratory performance test and was completed by individual students in a 40 minute class period. A sample of 219 physics students from rural, urban, public, and private schools in NY and PA were tested with the PLST in May 1990. Results of this study show that the PLST has usability, validity, and reliability as an assessment of basic skills (measuring and reporting) and higher order skills (planning and analysis). Participating teachers determined the PLST to be an appropriate and useful tool in evaluating individual student abilities. Content validity was established via evaluation by 'expert' high school physics teachers. The Pearson Correlation Coefficient was used to verify construct validity (r =.49) and inter-rater reliability (r =.81). The Cronbach Coefficient Alpha, which was used to determine internal consistency of each item, yielded strong positive results for the PLST. The outcomes of this study will be of particular interest to curriculum developers and classroom teachers

  15. Sex and Training Differences in Mental Rotation: A Behavioral and Neurophysiological Comparison of Gifted Achievers, Gifted Underachievers and Average Intelligent Achievers

    ERIC Educational Resources Information Center

    Bergner, Sabine; Neubauer, Aljoscha C.

    2011-01-01

    A male advantage in spatial abilities is assumed to underlie their superior performance in complex mathematical problems. In this study we investigated whether sex differences in mental rotation (MR) tasks are related to female underachievement and whether training effects of a MR training can be generalized across achievers and underachievers.…

  16. The Superior Lambert Algorithm

    NASA Astrophysics Data System (ADS)

    der, G.

    2011-09-01

    Lambert algorithms are used extensively for initial orbit determination, mission planning, space debris correlation, and missile targeting, just to name a few applications. Due to the significance of the Lambert problem in Astrodynamics, Gauss, Battin, Godal, Lancaster, Gooding, Sun and many others (References 1 to 15) have provided numerous formulations leading to various analytic solutions and iterative methods. Most Lambert algorithms and their computer programs can only work within one revolution, break down or converge slowly when the transfer angle is near zero or 180 degrees, and their multi-revolution limitations are either ignored or barely addressed. Despite claims of robustness, many Lambert algorithms fail without notice, and the users seldom have a clue why. The DerAstrodynamics lambert2 algorithm, which is based on the analytic solution formulated by Sun, works for any number of revolutions and converges rapidly at any transfer angle. It provides significant capability enhancements over every other Lambert algorithm in use today. These include improved speed, accuracy, robustness, and multirevolution capabilities as well as implementation simplicity. Additionally, the lambert2 algorithm provides a powerful tool for solving the angles-only problem without artificial singularities (pointed out by Gooding in Reference 16), which involves 3 lines of sight captured by optical sensors, or systems such as the Air Force Space Surveillance System (AFSSS). The analytic solution is derived from the extended Godal’s time equation by Sun, while the iterative method of solution is that of Laguerre, modified for robustness. The Keplerian solution of a Lambert algorithm can be extended to include the non-Keplerian terms of the Vinti algorithm via a simple targeting technique (References 17 to 19). Accurate analytic non-Keplerian trajectories can be predicted for satellites and ballistic missiles, while performing at least 100 times faster in speed than most

  17. Strategies to optimize lithium-ion supercapacitors achieving high-performance: Cathode configurations, lithium loadings on anode, and types of separator

    NASA Astrophysics Data System (ADS)

    Cao, Wanjun; Li, Yangxing; Fitch, Brian; Shih, Jonathan; Doung, Tien; Zheng, Jim

    2014-12-01

    The Li-ion capacitor (LIC) is composed of a lithium-doped carbon anode and an activated carbon cathode, which is a half Li-ion battery (LIB) and a half electrochemical double-layer capacitor (EDLC). LICs can achieve much more energy density than EDLC without sacrificing the high power performance advantage of capacitors over batteries. LIC pouch cells were assembled using activated carbon (AC) cathode and hard carbon (HC) + stabilized lithium metal power (SLMP®) anode. Different cathode configurations, various SLMP loadings on HC anode, and two types of separators were investigated to achieve the optimal electrochemical performance of the LIC. Firstly, the cathode binders study suggests that the PTFE binder offers improved energy and power performances for LIC in comparison to PVDF. Secondly, the mass ratio of SLMP to HC is at 1:7 to obtain the optimized electrochemical performance for LIC among all the various studied mass ratios between lithium loading amounts and active anode material. Finally, compared to the separator Celgard PP 3501, cellulose based TF40-30 is proven to be a preferred separator for LIC.

  18. Performance-based tests versus behavioral ratings in the assessment of executive functioning in preschoolers: associations with ADHD symptoms and reading achievement.

    PubMed

    Miranda, Ana; Colomer, Carla; Mercader, Jessica; Fernández, M Inmaculada; Presentación, M Jesús

    2015-01-01

    The early assessment of the executive processes using ecologically valid instruments is essential for identifying deficits and planning actions to deal with possible adverse consequences. The present study has two different objectives. The first objective is to analyze the relationship between preschoolers' performance on tests of Working Memory and Inhibition and parents' and teachers' ratings of these executive functions (EFs) using the Behavior Rating Inventory of Executive Function (BRIEF). The second objective consists of studying the predictive value of the different EF measures (performance-based test and rating scales) on Inattention and Hyperactivity/Impulsivity behaviors and on indicators of word reading performance. The participants in the study were 209 children in the last year of preschool, their teachers and their families. Performance-based tests of Working Memory and Inhibition were administered, as well as word reading measures (accuracy and speed). The parents and teachers filled out rating scales of the EF and typical behaviors of attention deficit hyperactivity disorder (ADHD) symptomatology. Moderate correlation values were found between the different EF assessments procedures, although the results varied depending on the different domains. Metacognition Index from the BRIEF presented stronger correlations with verbal working memory tests than with inhibition tests. Both the rating scales and the performance-based tests were significant predictors of Inattention and Hyperactivity/Impulsivity behaviors and the reading achievement measures. However, the BRIEF explained a greater percentage of variance in the case of the ADHD symptomatology, while the performance-based tests explained reading achievement to a greater degree. The implications of the findings for research and clinical practice are discussed.

  19. Performance-based tests versus behavioral ratings in the assessment of executive functioning in preschoolers: associations with ADHD symptoms and reading achievement

    PubMed Central

    Miranda, Ana; Colomer, Carla; Mercader, Jessica; Fernández, M. Inmaculada; Presentación, M. Jesús

    2015-01-01

    The early assessment of the executive processes using ecologically valid instruments is essential for identifying deficits and planning actions to deal with possible adverse consequences. The present study has two different objectives. The first objective is to analyze the relationship between preschoolers’ performance on tests of Working Memory and Inhibition and parents’ and teachers’ ratings of these executive functions (EFs) using the Behavior Rating Inventory of Executive Function (BRIEF). The second objective consists of studying the predictive value of the different EF measures (performance-based test and rating scales) on Inattention and Hyperactivity/Impulsivity behaviors and on indicators of word reading performance. The participants in the study were 209 children in the last year of preschool, their teachers and their families. Performance-based tests of Working Memory and Inhibition were administered, as well as word reading measures (accuracy and speed). The parents and teachers filled out rating scales of the EF and typical behaviors of attention deficit hyperactivity disorder (ADHD) symptomatology. Moderate correlation values were found between the different EF assessments procedures, although the results varied depending on the different domains. Metacognition Index from the BRIEF presented stronger correlations with verbal working memory tests than with inhibition tests. Both the rating scales and the performance-based tests were significant predictors of Inattention and Hyperactivity/Impulsivity behaviors and the reading achievement measures. However, the BRIEF explained a greater percentage of variance in the case of the ADHD symptomatology, while the performance-based tests explained reading achievement to a greater degree. The implications of the findings for research and clinical practice are discussed. PMID:25972833

  20. 75 FR 28542 - Superior Resource Advisory Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-21

    ... orient the new Superior Resource Advisory Committee members on their roles and responsibilities. DATES... of the roles and responsibilities of the Superior Resource Advisory Committee members; Election of... Forest Service Superior Resource Advisory Committee AGENCY: Forest Service, USDA. ACTION: Notice...

  1. Planar heterojunction perovskite solar cells with superior reproducibility.

    PubMed

    Jeon, Ye-Jin; Lee, Sehyun; Kang, Rira; Kim, Jueng-Eun; Yeo, Jun-Seok; Lee, Seung-Hoon; Kim, Seok-Soon; Yun, Jin-Mun; Kim, Dong-Yu

    2014-01-01

    Perovskite solar cells (PeSCs) have been considered one of the competitive next generation power sources. To date, light-to-electric conversion efficiencies have rapidly increased to over 10%, and further improvements are expected. However, the poor device reproducibility of PeSCs ascribed to their inhomogeneously covered film morphology has hindered their practical application. Here, we demonstrate high-performance PeSCs with superior reproducibility by introducing small amounts of N-cyclohexyl-2-pyrrolidone (CHP) as a morphology controller into N,N-dimethylformamide (DMF). As a result, highly homogeneous film morphology, similar to that achieved by vacuum-deposition methods, as well as a high PCE of 10% and an extremely small performance deviation within 0.14% were achieved. This study represents a method for realizing efficient and reproducible planar heterojunction (PHJ) PeSCs through morphology control, taking a major step forward in the low-cost and rapid production of PeSCs by solving one of the biggest problems of PHJ perovskite photovoltaic technology through a facile method. PMID:25377945

  2. Planar heterojunction perovskite solar cells with superior reproducibility

    PubMed Central

    Jeon, Ye-Jin; Lee, Sehyun; Kang, Rira; Kim, Jueng-Eun; Yeo, Jun-Seok; Lee, Seung-Hoon; Kim, Seok-Soon; Yun, Jin-Mun; Kim, Dong-Yu

    2014-01-01

    Perovskite solar cells (PeSCs) have been considered one of the competitive next generation power sources. To date, light-to-electric conversion efficiencies have rapidly increased to over 10%, and further improvements are expected. However, the poor device reproducibility of PeSCs ascribed to their inhomogeneously covered film morphology has hindered their practical application. Here, we demonstrate high-performance PeSCs with superior reproducibility by introducing small amounts of N-cyclohexyl-2-pyrrolidone (CHP) as a morphology controller into N,N-dimethylformamide (DMF). As a result, highly homogeneous film morphology, similar to that achieved by vacuum-deposition methods, as well as a high PCE of 10% and an extremely small performance deviation within 0.14% were achieved. This study represents a method for realizing efficient and reproducible planar heterojunction (PHJ) PeSCs through morphology control, taking a major step forward in the low-cost and rapid production of PeSCs by solving one of the biggest problems of PHJ perovskite photovoltaic technology through a facile method. PMID:25377945

  3. The Role of Lithium Conditioning in Achieving High Performance, Long Pulse H-mode Discharges in the NSTX and EAST Devices

    SciTech Connect

    Maingi, Rajesh; Mansfield, D. K.; Gong, X. Z.; Sun, Z.; Bell, M. G.

    2014-10-01

    In this paper, the role of lithium wall conditioning on the achievement of high performance, long pulse discharges in the National Spherical Torus Experiment (NSTX) and the Experimental Advanced Superconducting Tokamak (EAST) is documented. Common observations include recycling reduction and elimination of ELMs. In NSTX, lithium conditioning typically resulted in ELM-free operation with impurity accumulation, which was ameliorated e.g. with pulsed 3D fields to trigger controlled ELMs. Active lithium conditioning in EAST discharges has overcome this problem, producing an ELM-free Hmode with controlled density and impurities.

  4. Achieving a sustainable service advantage.

    PubMed

    Coyne, K P

    1993-01-01

    Many managers believe that superior service should play little or no role in competitive strategy; they maintain that service innovations are inherently copiable. However, the author states that this view is too narrow. For a company to achieve a lasting service advantage, it must base a new service on a capability gap that competitors cannot or will not copy.

  5. Unravelling the correlation between the aspect ratio of nanotubular structures and their electrochemical performance to achieve high-rate and long-life lithium-ion batteries.

    PubMed

    Tang, Yuxin; Zhang, Yanyan; Deng, Jiyang; Qi, Dianpeng; Leow, Wan Ru; Wei, Jiaqi; Yin, Shengyan; Dong, Zhili; Yazami, Rachid; Chen, Zhong; Chen, Xiaodong

    2014-12-01

    The fundamental understanding of the relationship between the nanostructure of an electrode and its electrochemical performance is crucial for achieving high-performance lithium-ion batteries (LIBs). In this work, the relationship between the nanotubular aspect ratio and electrochemical performance of LIBs is elucidated for the first time. The stirring hydrothermal method was used to control the aspect ratio of viscous titanate nanotubes, which were used to fabricate additive-free TiO2 -based electrode materials. We found that the battery performance at high charging/discharging rates is dramatically boosted when the aspect ratio is increased, due to the optimization of electronic/ionic transport properties within the electrode materials. The proof-of-concept LIBs comprising nanotubes with an aspect ratio of 265 can retain more than 86 % of their initial capacity over 6000 cycles at a high rate of 30 C. Such devices with supercapacitor-like rate performance and battery-like capacity herald a new paradigm for energy storage systems.

  6. ACHIEVING NEW SOURCE PERFORMANCE STANDARDS (NSPS) EMISSION STANDARDS THROUGH INTEGRATION OF LOW-NOx BURNERS WITH AN OPTIMIZATION PLAN FOR BOILER COMBUSTION

    SciTech Connect

    Wayne Penrod; David Moyeda

    2003-07-01

    The objective of this project is to demonstrate the use of an Integrated Combustion Optimization System to achieve NO{sub x} emissions levels in the range of 0.15 to 0.22 lb/MMBtu while simultaneously enabling increased power output. The project consists of the integration of low-NO{sub x} burners and advanced overfire air technology with various process measurement and control devices on the Holcomb Station Unit 1 boiler. The project includes the use of sophisticated neural networks or other artificial intelligence technologies and complex software that can optimize several operating parameters, including NO{sub x} emissions, boiler efficiency, and CO emissions. The program is being performed in three phases. In Phase I, the boiler is being equipped with sensors that can be used to monitor furnace conditions and coal flow to permit improvements in boiler operation. In Phase II, the boiler will be equipped with burner modifications designed to reduce NO{sub x} emissions and automated coal flow dampers to permit on-line fuel balancing. In Phase III, the boiler will be equipped with an overfire air system to permit deep reductions in NO{sub x} emissions to be achieved. Integration of the overfire air system with the improvements made in Phases I and II will permit optimization of the boiler performance, output, and emissions. During this reporting period, efforts were focused on completion of Phase I and Phase II activities. The low-NO{sub x} burner modifications, the coal flow dampers, and the coal flow monitoring system were procured and installed during a boiler outage in March 2003. During this reporting period, optimization tests were performed to evaluate system performance and identify optimum operating conditions for the installed equipment. The overfire air system process design activities and preliminary engineering design were completed.

  7. ACHIEVING NEW SOURCE PERFORMANCE STANDARDS (NSPS) EMISSION STANDARDS THROUGH INTEGRATION OF LOW-NOx BURNERS WITH AN OPTIMIZATION PLAN FOR BOILER COMBUSTION

    SciTech Connect

    Wayne Penrod; David Moyeda

    2003-04-01

    The objective of this project is to demonstrate the use of an Integrated Combustion Optimization System to achieve NO{sub x} emissions levels in the range of 0.15 to 0.22 lb/MMBtu while simultaneously enabling increased power output. The project consists of the integration of low-NO{sub x} burners and advanced overfire air technology with various process measurement and control devices on the Holcomb Station Unit 1 boiler. The project includes the use of sophisticated neural networks or other artificial intelligence technologies and complex software that can optimize several operating parameters, including NO{sub x} emissions, boiler efficiency, and CO emissions. The program is being performed in three phases. In Phase I, the boiler is being equipped with sensors that can be used to monitor furnace conditions and coal flow to permit improvements in boiler operation. In Phase II, the boiler will be equipped with burner modifications designed to reduce NO{sub x} emissions and automated coal flow dampers to permit on-line fuel balancing. In Phase III, the boiler will be equipped with an overfire air system to permit deep reductions in NO{sub x} emissions to be achieved. Integration of the overfire air system with the improvements made in Phases I and II will permit optimization of the boiler performance, output, and emissions. During this reporting period, efforts were focused on Phase I and Phase II activities. The furnace sensors were procured and installed in February 2003. Baseline testing was performed following the sensor installation. The low-NO{sub x} burner modifications, the coal flow dampers, and the coal flow monitoring system were procured and installed during a boiler outage in March 2003. Process design activities were performed to support design of the equipment installed and to develop specifications for the overfire air system. The overfire air system preliminary engineering design was initiated.

  8. The Classroom Performance System (CPS): Effects on student participation, attendance, and achievement in multicultural anatomy and physiology classes at South Texas College

    NASA Astrophysics Data System (ADS)

    Termos, Mohamad Hani

    2011-12-01

    The Classroom Performance System (CPS) is an instructional technology tool that increases student performance and addresses different learning styles. Instructional technologies are used to promote active learning; however, student embarrassment issue in a multicultural setting is not addressed. This study assessed the effect of the CPS on student participation, attendance, and achievement in multicultural college-level anatomy and physiology classes at South Texas College, where the first spoken language is not English. Quantitative method and quasi-experimental design were employed and comparative statistic methods and pre-post tests were used to collect the data. Participants were college students and sections of study were selected by convenient sampling. Participation was 100% during most of the lectures held and participation rate did not strike above 68% in control group. Attendance was significantly higher in CPS sections than the control group as shown by t-tests. Experimental sections had a higher increase in the pre-post test scores and student averages on lecture exams increased at a higher rate as compared to the control group. Therefore, the CPS increased student participation, attendance, and achievement in multicultural anatomy and physiology classes. The CPS can be studied in other settings where the first spoken language is English or in other programs, such as special education programs. Additionally, other variables can be studied and other methodologies can be employed.

  9. Academic Momentum at University/College: Exploring the Roles of Prior Learning, Life Experience, and Ongoing Performance in Academic Achievement across Time

    ERIC Educational Resources Information Center

    Martin, Andrew J.; Wilson, Rachel; Liem, Gregory Arief D.; Ginns, Paul

    2014-01-01

    In the context of "academic momentum," a longitudinal study of university students (N = 904) showed high school achievement and ongoing university achievement predicted subsequent achievement through university. However, the impact of high school achievement diminished, while additive effects of ongoing university achievement continued.…

  10. [Superior vena cava syndrome--surgical solution--case report].

    PubMed

    Galie, N; Vasile, R; Savu, C; Petreanu, C; Grigorie, V; Tabacu, E

    2010-01-01

    The patient of 52-year-old smoker was admitted in emergency with headaches, dyspnea, oedema and cyanosis of the cephalic extremity and of the superior members. This signs and symptoms suggest a superior vena cava sindrom. Thoracic CT scan shows the thrombosis of the superior vena cava and a tumor localized in the Bariety's Lodge of about 30/40 mm witch is around the right lateral wall of the traheea.This tumor is also tangent to the superior the superior vena cava. The patient was operated by total median sternotomy. By this approach we performed a complete excision of the mediastinal tumor mass. After that we effected a longitudinal cavotomy, we took out the endoluminal clot and we sutured the superior vena cava. The histological diagnosis of the mediastinal tumor was adenocarcinoma tubular-papillary moderately differentiated. The evolution post operative period was favorable the superior vena cava sindrom was a complet remission. The thoracic CT scan control after 9 months later didn't show a local relapse and blood flow was normally throw the superior vena cava.

  11. [Mitral surgery by superior biatrial septotomy].

    PubMed

    Saade, A; Delepine, G; Lemaitre, C; Baehrel, B

    1995-01-01

    The superior biatrial septotomy approach consists of two semicircular right atrial and septal incisions joined at the superior end of the interatrial septum and extended across the dome of the left atrium, allowing exposure of the mitral valve by reflecting the ventricular side using stay sutures. From 1991 to 1993, 81 patients underwent mitral valve surgery by this technic. Mitral valve operation was combined with other cardiac procedures in 30 patients (37%) and was performed as a second operation in 21 patients (25.9%). Duration of cardiopulmonary bypass and aortic occlusion was not significantly different from that of patients operated via a conventional left atrial approach. The five hospital deaths (6.2%) were not related to this operative approach. Only 2 patients (3.3%) with preoperative in sinus rythm were discharged in atrial fibrillation after operation. In one patient (1.6%), atrioventricular block appeared at late follow-up. There were no cases of bleeding, atrioventricular nodal dysfunction or intra-atrial shunting related to the approach. This approach provides excellent exposure of the mitral valve even in unfavorable situations such as a small left atrium, dense adhesions from previous procedures or a previously implanted aortic prosthesis, without damage to various cardiac structures due to excessive traction. No retractor or vena cava repair are required. These data support a wide application of the superior biatrial septotomy approach in mitral valve surgery.

  12. The letter height superiority illusion.

    PubMed

    New, Boris; Doré-Mazars, Karine; Cavézian, Céline; Pallier, Christophe; Barra, Julien

    2016-02-01

    Letters are identified better when they are embedded within words rather than within pseudowords, a phenomenon known as the word superiority effect (Reicher in Journal of Experimental Psychology, 81, 275-280, 1969). This effect is, inter alia, accounted for by the interactive-activation model (McClelland & Rumelhart in Psychological Review, 88, 375-407, 1981) through feedback from word to letter nodes. In this study, we investigated whether overactivation of features could lead to perceptual bias, wherein letters would be perceived as being taller than pseudoletters, or words would be perceived as being taller than pseudowords. In two experiments, we investigated the effects of letter and lexical status on the perception of size. Participants who had to compare the heights of letters and pseudoletters, or of words and pseudowords, indeed perceived the former stimuli as being taller than the latter. Possible alternative interpretations of this height superiority effect for letters and words are discussed. PMID:26370216

  13. Superior sulcus tumors (Pancoast tumors).

    PubMed

    Marulli, Giuseppe; Battistella, Lucia; Mammana, Marco; Calabrese, Francesca; Rea, Federico

    2016-06-01

    Superior Sulcus Tumors, frequently termed as Pancoast tumors, are a wide range of tumors invading the apical chest wall. Due to its localization in the apex of the lung, with the potential invasion of the lower part of the brachial plexus, first ribs, vertebrae, subclavian vessels or stellate ganglion, the superior sulcus tumors cause characteristic symptoms, like arm or shoulder pain or Horner's syndrome. The management of superior sulcus tumors has dramatically evolved over the past 50 years. Originally deemed universally fatal, in 1956, Shaw and Paulson introduced a new treatment paradigm with combined radiotherapy and surgery ensuring 5-year survival of approximately 30%. During the 1990s, following the need to improve systemic as well as local control, a trimodality approach including induction concurrent chemoradiotherapy followed by surgical resection was introduced, reaching 5-year survival rates up to 44% and becoming the standard of care. Many efforts have been persecuted, also, to obtain higher complete resection rates using appropriate surgical approaches and involving multidisciplinary team including spine surgeon or vascular surgeon. Other potential treatment options are under consideration like prophylactic cranial irradiation or the addition of other chemotherapy agents or biologic agents to the trimodality approach.

  14. Superior sulcus tumors (Pancoast tumors).

    PubMed

    Marulli, Giuseppe; Battistella, Lucia; Mammana, Marco; Calabrese, Francesca; Rea, Federico

    2016-06-01

    Superior Sulcus Tumors, frequently termed as Pancoast tumors, are a wide range of tumors invading the apical chest wall. Due to its localization in the apex of the lung, with the potential invasion of the lower part of the brachial plexus, first ribs, vertebrae, subclavian vessels or stellate ganglion, the superior sulcus tumors cause characteristic symptoms, like arm or shoulder pain or Horner's syndrome. The management of superior sulcus tumors has dramatically evolved over the past 50 years. Originally deemed universally fatal, in 1956, Shaw and Paulson introduced a new treatment paradigm with combined radiotherapy and surgery ensuring 5-year survival of approximately 30%. During the 1990s, following the need to improve systemic as well as local control, a trimodality approach including induction concurrent chemoradiotherapy followed by surgical resection was introduced, reaching 5-year survival rates up to 44% and becoming the standard of care. Many efforts have been persecuted, also, to obtain higher complete resection rates using appropriate surgical approaches and involving multidisciplinary team including spine surgeon or vascular surgeon. Other potential treatment options are under consideration like prophylactic cranial irradiation or the addition of other chemotherapy agents or biologic agents to the trimodality approach. PMID:27429965

  15. Superior sulcus tumors (Pancoast tumors)

    PubMed Central

    Battistella, Lucia; Mammana, Marco; Calabrese, Francesca; Rea, Federico

    2016-01-01

    Superior Sulcus Tumors, frequently termed as Pancoast tumors, are a wide range of tumors invading the apical chest wall. Due to its localization in the apex of the lung, with the potential invasion of the lower part of the brachial plexus, first ribs, vertebrae, subclavian vessels or stellate ganglion, the superior sulcus tumors cause characteristic symptoms, like arm or shoulder pain or Horner’s syndrome. The management of superior sulcus tumors has dramatically evolved over the past 50 years. Originally deemed universally fatal, in 1956, Shaw and Paulson introduced a new treatment paradigm with combined radiotherapy and surgery ensuring 5-year survival of approximately 30%. During the 1990s, following the need to improve systemic as well as local control, a trimodality approach including induction concurrent chemoradiotherapy followed by surgical resection was introduced, reaching 5-year survival rates up to 44% and becoming the standard of care. Many efforts have been persecuted, also, to obtain higher complete resection rates using appropriate surgical approaches and involving multidisciplinary team including spine surgeon or vascular surgeon. Other potential treatment options are under consideration like prophylactic cranial irradiation or the addition of other chemotherapy agents or biologic agents to the trimodality approach. PMID:27429965

  16. Achieving highly effective non-biofouling performance for polypropylene membranes modified by UV-induced surface graft polymerization of two oppositely charged monomers.

    PubMed

    Zhao, Yong-Hong; Zhu, Xiao-Ying; Wee, Kin-Ho; Bai, Renbi

    2010-02-25

    A major problem in membrane technology for applications such as wastewater treatment or desalination is often the loss of membrane permeability due to biofouling initiated from protein adsorption and biofilm formation on the membrane surface. In this study, we developed a relatively simple and yet versatile approach to prepare polypropylene (PP) membrane with highly effective non-biofouling performance. Copolymer brushes were grafted to the surface of PP membrane through UV-induced polymerization of two oppositely charged monomers, i.e., [2-(methacryloyloxy)ethyl]trimethylammonium chloride (TM) and 3-sulfopropyl methacrylate potassium salt (SA), with varying TM:SA molar ratios. Surface analysis with scanning electron microscope (SEM) clearly showed the grafted copolymer brushes on the membrane surfaces and that with X-ray photoelectron spectroscope (XPS) revealed a similar TM:SA ratio of the grafted copolymer brushes to that of the monomer solution used for the polymerization. Water contact angle measurements indicated that the hydrophilicity of the membrane surfaces was remarkably improved by the grafting of the TM/SA copolymer brushes, with the lowest water contact angle of 27 degrees being achieved at the TM:SA ratio of around 1:1. Experiments for antiprotein adsorption with bovine serum album (BSA) and lysozyme (LYZ) and antibiofilm formation with Escherichia coli (E. coli) demonstrated a great dependence of the membrane performance on the TM:SA ratios of the grafted copolymer brushes. It was found that the characteristics of the surface charges of the membrane surfaces played a very important role in the non-biofouling performance, and the membrane surface with balanced positive and negative charges showed the best non-biofouling performance for the proteins and bacteria tested in this study.

  17. The impact of nursing students' chemistry learning performance assessment in Taiwan: competitive versus non-competitive student team achievement division approaches

    NASA Astrophysics Data System (ADS)

    Wang, Kai-Ping

    2012-07-01

    Purpose: The purpose of this study was to determine the effectiveness of competitive Student Team Achievement Division (STAD), non-competitive STAD, and traditional learning on chemistry learning and learning perceptions. Sample, design and methods: By adopting the STAD approach, this study examined 144 nursing students at a five-year junior college in northern Taiwan during the first semester (totaling 18 weeks) of the 2008 academic year. Results: The findings reveal that both a heterogeneous group with external pressure (involving competitive STAD) and a friendship group with affective pressure (involving traditional learning) enhance group cohesion and assist students' meaningful learning; the heterogeneous group without extra pressure (involving non-competitive STAD), by contrast, fails because of apathy and lassitude. Moreover, learning effectiveness will obviously predominate until the learning strategy continues for a long period or at least one semester. Conclusions: This study revealed that the learning performance level of the competitive STAD group is significantly different from that of the non-competitive STAD group; and the learning performance level of the traditional group is significantly different from that of the non-competitive STAD group. Both the competitive STAD group and traditional group of medium ability students are significantly different from the non-competitive STAD group. Low-ability students from the competitive STAD group are significantly different from those of the non-competitive STAD, though no significant differences were found in learning perception. However, both a lack of friendship and a lack of ability in using algorithms may affect students' chemistry learning. Furthermore, gender imbalance, educational culture, and group emotions are factors that may influence student learning performance. Further study should focus on the use of grouping, improve responsibility in group discussion, and investigate group interaction

  18. The role of aerobic fitness in cortical thickness and mathematics achievement in preadolescent children.

    PubMed

    Chaddock-Heyman, Laura; Erickson, Kirk I; Kienzler, Caitlin; King, Matthew; Pontifex, Matthew B; Raine, Lauren B; Hillman, Charles H; Kramer, Arthur F

    2015-01-01

    Growing evidence suggests that aerobic fitness benefits the brain and cognition during childhood. The present study is the first to explore cortical brain structure of higher fit and lower fit 9- and 10-year-old children, and how aerobic fitness and cortical thickness relate to academic achievement. We demonstrate that higher fit children (>70th percentile VO2max) showed decreased gray matter thickness in superior frontal cortex, superior temporal areas, and lateral occipital cortex, coupled with better mathematics achievement, compared to lower fit children (<30th percentile VO2max). Furthermore, cortical gray matter thinning in anterior and superior frontal areas was associated with superior arithmetic performance. Together, these data add to our knowledge of the biological markers of school achievement, particularly mathematics achievement, and raise the possibility that individual differences in aerobic fitness play an important role in cortical gray matter thinning during brain maturation. The establishment of predictors of academic performance is key to helping educators focus on interventions to maximize learning and success across the lifespan.

  19. The Role of Aerobic Fitness in Cortical Thickness and Mathematics Achievement in Preadolescent Children

    PubMed Central

    Chaddock-Heyman, Laura; Erickson, Kirk I.; Kienzler, Caitlin; King, Matthew; Pontifex, Matthew B.; Raine, Lauren B.; Hillman, Charles H.; Kramer, Arthur F.

    2015-01-01

    Growing evidence suggests that aerobic fitness benefits the brain and cognition during childhood. The present study is the first to explore cortical brain structure of higher fit and lower fit 9- and 10-year-old children, and how aerobic fitness and cortical thickness relate to academic achievement. We demonstrate that higher fit children (>70th percentile VO2max) showed decreased gray matter thickness in superior frontal cortex, superior temporal areas, and lateral occipital cortex, coupled with better mathematics achievement, compared to lower fit children (<30th percentile VO2max). Furthermore, cortical gray matter thinning in anterior and superior frontal areas was associated with superior arithmetic performance. Together, these data add to our knowledge of the biological markers of school achievement, particularly mathematics achievement, and raise the possibility that individual differences in aerobic fitness play an important role in cortical gray matter thinning during brain maturation. The establishment of predictors of academic performance is key to helping educators focus on interventions to maximize learning and success across the lifespan. PMID:26267897

  20. Feeding Artery of Laryngeal and Hypopharyngeal Cancers: Role of the Superior Thyroid Artery in Superselective Intraarterial Chemotherapy

    SciTech Connect

    Terayama, Noboru Sanada, Junichiro; Matsui, Osamu; Kobayashi, Satoshi; Kawashima, Hiroko; Yamashiro, Masashi; Takanaka, Tsuyoshi; Kumano, Tomoyasu; Yoshizaki, Tomokazu; Furukawa, Mitsuru

    2006-08-15

    The purpose of this study was to elucidate the role of the superior thyroid artery in intra-arterial infusion chemotherapy for laryngeal and hypopharyngeal cancers. Thirty-nine patients with laryngeal cancer and 29 patients with hypopharyngeal cancer underwent intra-arterial infusion chemotherapy. We performed a retrospective analysis of the feeding arteries confirmed by computed tomography during selective arteriography and compared the results with the extent of the tumors. In 14 of 39 laryngeal and 15 of 29 hypopharyngeal cancers, the tumor did not cross the midline (group 1). In the remaining 25 and 14 cancers, respectively, the tumor crossed the midline or located in the center (group 2). For 13 of 14 laryngeal and 7 of 15 hypopharyngeal cancers in group 1 and for 6 of 25 laryngeal cancers in group 2, the entire tumor was contrast enhanced by the ipsilateral superior thyroid and/or superior laryngeal artery. For 12 of 25 laryngeal and 1 of 14 hypopharyngeal cancers in group 2, the entire tumor was contrast enhanced by the bilateral superior thyroid artery. For the other patients, infusion via the other arterial branches such as the inferior thyroid and the lingual arteries were needed to achieve contrast enhancement of the entire tumor. Superselective intra-arterial chemotherapy for laryngeal cancer from the superior thyroid artery is appropriate, whereas that for hypopharyngeal cancer is less sufficient. To accomplish contrast enhancement of the entire tumor, additional intra-arterial infusion from other arteries such as the inferior thyroid artery is often necessary.

  1. The Value of Extracurricular Support in Increased Student Achievement: An Assessment of a Pupil Personnel Model Including School Counselors and School Psychologists Concerning Student Achievement as Measured by an Academic Performance Index

    ERIC Educational Resources Information Center

    Goodman, Greg S.; Young, I. Phillip

    2006-01-01

    This study examined two models of extra-curricular support for enhancing the academic achievement of students as measured by state mandated test scores. One management model includes the use of school counselors as enhancers of the educational process while the other model addresses the contribution of school psychologists. To differentiate…

  2. An investigation of signal performance enhancements achieved through innovative pixel design across several generations of indirect detection, active matrix, flat-panel arrays

    SciTech Connect

    Antonuk, Larry E.; Zhao Qihua; El-Mohri, Youcef; Du Hong; Wang Yi; Street, Robert A.; Ho, Jackson; Weisfield, Richard; Yao, William

    2009-07-15

    Active matrix flat-panel imager (AMFPI) technology is being employed for an increasing variety of imaging applications. An important element in the adoption of this technology has been significant ongoing improvements in optical signal collection achieved through innovations in indirect detection array pixel design. Such improvements have a particularly beneficial effect on performance in applications involving low exposures and/or high spatial frequencies, where detective quantum efficiency is strongly reduced due to the relatively high level of additive electronic noise compared to signal levels of AMFPI devices. In this article, an examination of various signal properties, as determined through measurements and calculations related to novel array designs, is reported in the context of the evolution of AMFPI pixel design. For these studies, dark, optical, and radiation signal measurements were performed on prototype imagers incorporating a variety of increasingly sophisticated array designs, with pixel pitches ranging from 75 to 127 {mu}m. For each design, detailed measurements of fundamental pixel-level properties conducted under radiographic and fluoroscopic operating conditions are reported and the results are compared. A series of 127 {mu}m pitch arrays employing discrete photodiodes culminated in a novel design providing an optical fill factor of {approx}80% (thereby assuring improved x-ray sensitivity), and demonstrating low dark current, very low charge trapping and charge release, and a large range of linear signal response. In two of the designs having 75 and 90 {mu}m pitches, a novel continuous photodiode structure was found to provide fill factors that approach the theoretical maximum of 100%. Both sets of novel designs achieved large fill factors by employing architectures in which some, or all of the photodiode structure was elevated above the plane of the pixel addressing transistor. Generally, enhancement of the fill factor in either discrete or

  3. An investigation of signal performance enhancements achieved through innovative pixel design across several generations of indirect detection, active matrix, flat-panel arrays

    PubMed Central

    Antonuk, Larry E.; Zhao, Qihua; El-Mohri, Youcef; Du, Hong; Wang, Yi; Street, Robert A.; Ho, Jackson; Weisfield, Richard; Yao, William

    2009-01-01

    Active matrix flat-panel imager (AMFPI) technology is being employed for an increasing variety of imaging applications. An important element in the adoption of this technology has been significant ongoing improvements in optical signal collection achieved through innovations in indirect detection array pixel design. Such improvements have a particularly beneficial effect on performance in applications involving low exposures and∕or high spatial frequencies, where detective quantum efficiency is strongly reduced due to the relatively high level of additive electronic noise compared to signal levels of AMFPI devices. In this article, an examination of various signal properties, as determined through measurements and calculations related to novel array designs, is reported in the context of the evolution of AMFPI pixel design. For these studies, dark, optical, and radiation signal measurements were performed on prototype imagers incorporating a variety of increasingly sophisticated array designs, with pixel pitches ranging from 75 to 127 μm. For each design, detailed measurements of fundamental pixel-level properties conducted under radiographic and fluoroscopic operating conditions are reported and the results are compared. A series of 127 μm pitch arrays employing discrete photodiodes culminated in a novel design providing an optical fill factor of ∼80% (thereby assuring improved x-ray sensitivity), and demonstrating low dark current, very low charge trapping and charge release, and a large range of linear signal response. In two of the designs having 75 and 90 μm pitches, a novel continuous photodiode structure was found to provide fill factors that approach the theoretical maximum of 100%. Both sets of novel designs achieved large fill factors by employing architectures in which some, or all of the photodiode structure was elevated above the plane of the pixel addressing transistor. Generally, enhancement of the fill factor in either discrete or continuous

  4. The Arthroscopic Superior Capsular Reconstruction.

    PubMed

    Adams, Christopher R; Denard, Patrick J; Brady, Paul C; Hartzler, Robert U; Burkhart, Stephen S

    2016-01-01

    In a subset of patients with rotator cuff tears, the glenohumeral joint has minimal degenerative changes and the rotator cuff tendon is either irreparable or very poor quality and unlikely to heal. Reverse shoulder arthroplasty (RSA) is often considered for these patients despite the lack of glenohumeral arthritis. However, due to the permanent destruction of the glenohumeral articular surfaces, complication rates, and concerns about implant longevity with RSA, we believe the superior capsular reconstruction (SCR) is a viable alternative. In this article, we describe our technique for the SCR. PMID:27552457

  5. INTERDEPENDENT SUPERIORITY AND INFERIORITY FEELINGS

    PubMed Central

    Ingham, Harrington V.

    1949-01-01

    It is postulated that in neurotic persons who have unrealistic feelings of superiority and inferiority the two are interdependent. This is a departure from the concept of previous observers that either one or the other is primary and its opposite is overcompensation. The author postulates considerable parallelism, with equal importance for each. He submits that the neurotic person forms two logic-resistant compartments for the two opposed self-estimates and that treatment which makes inroads of logic upon one compartment, simultaneously does so upon the other. Two examples are briefly reported. The neurotic benefits sought in exaggeration of capability are the same as those sought in insistence upon inferiority: Presumption of superiority at once bids for approbation and delivers the subject from the need to prove himself worthy of it in dreaded competition; exaggeration of incapability baits sympathy and makes competition unnecessary because failure is conceded. Some of the characteristics of abnormal self-estimates that distinguish them from normal are: Preoccupation with self, resistance to logical explanation of personality problems, inconsistency in reasons for beliefs in adequacy on the one hand and inadequacy on the other, unreality, rationalization of faults, and difficulty and vacillation in the selection of adequate goals. PMID:15390573

  6. An analysis of factors correlated with the achievement of the goal standard for the science portion of the Connecticut Academic Performance Test

    NASA Astrophysics Data System (ADS)

    Kmetz, Barbara Fotta

    2001-07-01

    This study sought to identify factors that could be used to predict the success of students on the science portion of the grade ten Connecticut Academic Performance Test (CAPT). While the Connecticut State Department of Education measures student achievement in mathematics, reading and writing in grades 4, 6, and 8, science is assessed only in the grade ten CAPT. Since the CAPT science test does not identify specific areas in need of improvement, it is not possible to determine causes for low test scores. To address this, the study investigated the predictive values of the grade eight Mastery Tests in mathematics and reading, the student ability scores of the Otis-Lennon School Ability Index, and grades in prior science courses. The research sample consisted of five hundred and twenty-five students, member of the graduating classes of 2000 and 2001 in a large suburban high school. Students in the study had participated in the district testing program and their scores for the grade seven Otis-Lennon School Ability Test (OLSAT), the grade eight Connecticut Mastery Tests (CMT) and the grade ten Connecticut Academic Performance Tests (CAPT) were available for analysis. This study investigated correlations between student achievement on the CMT and the science subtest of the CAPT, between OLSAT scores and the CAPT science scores, and between grades in ninth grade science and CAPT science scores. Scores were disaggregated by gender and by course level. Hypotheses 1, 2, 3 and 4 investigated the Pearson Product Moment Correlations of the OLSAT, CMT and course grades with scores on the science portion of the CAPT. Hypothesis 5 compared the scores of male and female students, using the t-test of independent sample means. Calculations showed moderate correlations for hypotheses 1--4, and the hypotheses were accepted. Hypothesis 5 was accepted for one class and rejected for the other. On the whole, female students received higher course grades and lower standardized test

  7. 76 FR 11193 - Superior Resource Advisory Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-01

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF AGRICULTURE Forest Service Superior Resource Advisory Committee AGENCY: Forest Service, USDA. ACTION: Notice of meeting. SUMMARY: The Superior Resource Advisory Committee will meet in Duluth, Minnesota. The...

  8. 75 FR 65296 - Superior Resource Advisory Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-22

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF AGRICULTURE Forest Service Superior Resource Advisory Committee AGENCY: Forest Service, USDA. ACTION: Notice of meeting. SUMMARY: The Superior Resource Advisory Committee will meet in Duluth, Minnesota. The...

  9. Do high functioning persons with autism present superior spatial abilities?

    PubMed

    Caron, M-J; Mottron, L; Rainville, C; Chouinard, S

    2004-01-01

    This series of experiments was aimed at assessing spatial abilities in high functioning individuals with autism (HFA), using a human-size labyrinth. In the context of recent findings that the performance of individuals with HFA was superior to typically developing individuals in several non-social cognitive operations, it was expected that the HFA group would outperform a typically developing comparison group matched on full-scale IQ. Results showed that individuals with autism performed all spatial tasks at a level at least equivalent to the typically developing comparison group. No differences between groups were found in route and survey tasks. Superior performance for individuals with HFA was found in tasks involving maps, in the form of superior accuracy in graphic cued recall of a path, and shorter learning times in a map learning task. We propose that a superior ability to detect [Human Perception and Performance 27 (3) (2001) 719], match [Journal of Child Psychology and Psychiatry 34 (1993) 1351] and reproduce [Journal of Child Psychology and Psychiatry 40 (5) (1999) 743] simple visual elements yields superior performance in tasks relying on the detection and graphic reproduction of the visual elements composing a map. Enhanced discrimination, detection, and memory for visually simple patterns in autism may account for the superior performance of persons with autism on visuo-spatial tasks that heavily involve pattern recognition, either in the form of recognizing and memorizing landmarks or in detecting the similarity between map and landscape features. At a neuro-anatomical level, these findings suggest an intact dorso-lateral pathway, and enhanced performance in non social tasks relying on the infero-temporal pathway. PMID:14728920

  10. Achieving New Source Performance Standards (NSPS) Emission Standards Through Integration of Low-NOx Burners with an Optimization Plan for Boiler Combustion

    SciTech Connect

    Wayne Penrod

    2006-12-31

    The objective of this project was to demonstrate the use of an Integrated Combustion Optimization System to achieve NO{sub X} emission levels in the range of 0.15 to 0.22 lb/MMBtu while simultaneously enabling increased power output. The project plan consisted of the integration of low-NO{sub X} burners and advanced overfire air technology with various process measurement and control devices on the Holcomb Station Unit 1 boiler. The plan included the use of sophisticated neural networks or other artificial intelligence technologies and complex software to optimize several operating parameters, including NO{sub X} emissions, boiler efficiency, and CO emissions. The program was set up in three phases. In Phase I, the boiler was equipped with sensors that can be used to monitor furnace conditions and coal flow to permit improvements in boiler operation. In Phase II, the boiler was equipped with burner modifications designed to reduce NO{sub X} emissions and automated coal flow dampers to permit on-line fuel balancing. In Phase III, the boiler was to be equipped with an overfire air system to permit deep reductions in NO{sub X} emissions. Integration of the overfire air system with the improvements made in Phases I and II would permit optimization of boiler performance, output, and emissions. This report summarizes the overall results from Phases I and II of the project. A significant amount of data was collected from the combustion sensors, coal flow monitoring equipment, and other existing boiler instrumentation to monitor performance of the burner modifications and the coal flow balancing equipment.

  11. Activities on Realization of High-Power and Steady-State ECRH System and Achievement of High Performance Plasmas in LHD

    SciTech Connect

    Shimozuma, T.; Kubo, S.; Yoshimura, Y.; Igami, H.; Takahashi, H.; Ikeda, R.; Tamura, N.; Kobayashi, S.; Ito, S.; Mizuno, Y.; Takita, Y.; Mutoh, T.; Minami, R.; Kariya, T.; Imai, T.; Idei, H.; Shapiro, M. A.; Temkin, R. J.; Felici, F.; Goodman, T.

    2009-11-26

    Electron Cyclotron Resonance Heating (ECRH) has contributed to the achievement of high performance plasma production, high electron temperature plasmas and sustainment of steady-state plasmas in the Large Helical Device (LHD). Our immediate targets of upgrading the ECRH system are 5 MW several seconds and 1 MW longer than one hour power injection into LHD. The improvement will greatly extend the plasma parameter regime. For that purpose, we have been promoting the development and installation of 77 GHz/1-1.5 MW/several seconds and 0.3 MW/CW gyrotrons in collaboration with University of Tsukuba. The transmission lines are re-examined and improved for high and CW power transmission. In the recent experimental campaign, two 77 GHz gyrotrons were operated. One more gyrotron, which was designed for 1.5 MW/2 s output, was constructed and is tested. We have been promoting to improve total ECRH efficiency for efficient gyrotron-power use and efficient plasma heating, e.g. a new waveguide alignment method and mode-content analysis and the feedback control of the injection polarization. In the last experimental campaign, the 77 GHz gyrotrons were used in combination with the existing 84 GHz range and 168 GHz gyrotrons. Multi-frequency ECRH system is more flexible in plasma heating experiments and diagnostics. A lot of experiments have been performed in relation to high electron temperature plasmas by realization of the core electron-root confinement (CERC), electron cyclotron current drive (ECCD), Electron Bernstein Wave heating, and steady-state plasma sustainment. Some of the experimental results are briefly described.

  12. Laparoscopic Management of Superior Mesenteric Artery Syndrome

    PubMed Central

    Fenoglio, Michael E.

    2003-01-01

    Objectives: The differential diagnosis of intestinal obstruction includes mechanical obstruction, obstruction secondary to systemic disease, and idiopathic intestinal pseudo-obstruction. The causes of these are extensive; however, the majority of cases involve a mechanical cause. Superior mesenteric artery syndrome (SMAS) is a rare and controversial form of mechanical obstruction with just over 300 well-defined cases described in the literature. The diagnosis is often difficult to establish, even after surgery. In addition, this syndrome sometimes may be managed conservatively, leaving a definitive diagnosis unproven. We describe herein 2 patients with SMAS successfully treated with laparoscopic duodenojejunostomy. Methods: Two cases of SMAS occurred in young men ages 23 and 34. The workup included a consultation with a gastroenterologist, an upper gastrointestinal (GI) endoscopy, upper GI series with small bowel follow-through, computed tomography scan, ultrasound of the abdomen, and abdominal aortogram. This diagnosis was established after consultation with the surgeon and the gastroenterologist in each case. Results: Laparoscopic duodenojejunostomy was performed in each case, and both patients have had complete resolution of their preoperative symptoms. Conclusions: A laparoscopic approach to the management of superior mesenteric artery syndrome is a reasonable and successful way of treating these patients. PMID:12856847

  13. U.S. Math Performance in Global Perspective: How Well Does Each State Do at Producing High-Achieving Students? PEPG Report No.: 10-19

    ERIC Educational Resources Information Center

    Hanushek, Eric A.; Peterson, Paul E.; Woessmann, Ludger

    2010-01-01

    To see how well U.S. schools do at producing high-achieving math students, the authors compare the percentage of U.S. public and private school students in the graduating Class of 2009 who were highly accomplished in mathematics in each of the 50 states and in 10 urban districts to percentages of high achievers in 56 other countries. Their…

  14. The Academic Achievement and Functional Performance of Youth with Disabilities. A Report from the National Longitudinal Transition Study-2 (NLTS2). NCSER 2006-3000

    ERIC Educational Resources Information Center

    Wagner, Mary; Newman, Lynn; Cameto, Renee; Levine, Phyllis

    2006-01-01

    Background: To provide a national picture of the academic achievements of American students, the National Center for Education Statistics has administered the National Assessment of Educational Progress (NAEP) periodically since 1969, but there has been no similar national picture of the academic achievement of youth with disabilities. Purpose: To…

  15. The Predictability of Enrolment and First-Year University Results from Secondary School Performance: The New Zealand National Certificate of Educational Achievement

    ERIC Educational Resources Information Center

    Shulruf, Boaz; Hattie, John; Tumen, Sarah

    2008-01-01

    This study investigates the predictive correlations between results from the New Zealand National Certificate of Educational Achievement (NCEA), a standards-based qualification, and university grade point averages achieved by first-year students in one large New Zealand University (and, for comparison purposes, also presents correlations from the…

  16. Superior underwater vision in a human population of sea gypsies.

    PubMed

    Gislén, Anna; Dacke, Marie; Kröger, Ronald H H; Abrahamsson, Maths; Nilsson, Dan-Eric; Warrant, Eric J

    2003-05-13

    Humans are poorly adapted for underwater vision. In air, the curved corneal surface accounts for two-thirds of the eye's refractive power, and this is lost when air is replaced by water. Despite this, some tribes of sea gypsies in Southeast Asia live off the sea, and the children collect food from the sea floor without the use of visual aids. This is a remarkable feat when one considers that the human eye is not focused underwater and small objects should remain unresolved. We have measured the visual acuity of children in a sea gypsy population, the Moken, and found that the children see much better underwater than one might expect. Their underwater acuity (6.06 cycles/degree) is more than twice as good as that of European children (2.95 cycles/degree). Our investigations show that the Moken children achieve their superior underwater vision by maximally constricting the pupil (1.96 mm compared to 2.50 mm in European children) and by accommodating to the known limit of human performance (15-16 D). This extreme reaction-which is routine in Moken children-is completely absent in European children. Because they are completely dependent on the sea, the Moken are very likely to derive great benefit from this strategy.

  17. Ethnic differences in adolescent achievement. An ecological perspective.

    PubMed

    Steinberg, L; Dornbusch, S M; Brown, B B

    1992-06-01

    Using data collected from a large sample of high school students, the authors challenge three widely held explanations for the superior school performance of Asian-American adolescents, and the inferior performance of African- and Hispanic-American adolescents: group differences in (a) parenting practices, (b) familial values about education, and (c) youngsters' beliefs about the occupational rewards of academic success. They found that White youngsters benefit from the combination of authoritative parenting and peer support for achievement, whereas Hispanic youngsters suffer from a combination of parental authoritarianism and low peer support. Among Asian-American students, peer support for academic excellence offsets the negative consequences of authoritarian parenting. Among African-American youngsters, the absence of peer support for achievement undermines the positive influence of authoritative parenting. PMID:1616171

  18. Increasing Male Academic Achievement

    ERIC Educational Resources Information Center

    Jackson, Barbara Talbert

    2008-01-01

    The No Child Left Behind legislation has brought greater attention to the academic performance of American youth. Its emphasis on student achievement requires a closer analysis of assessment data by school districts. To address the findings, educators must seek strategies to remedy failing results. In a mid-Atlantic district of the Unites States,…

  19. Explorations in achievement motivation

    NASA Technical Reports Server (NTRS)

    Helmreich, Robert L.

    1982-01-01

    Recent research on the nature of achievement motivation is reviewed. A three-factor model of intrinsic motives is presented and related to various criteria of performance, job satisfaction and leisure activities. The relationships between intrinsic and extrinsic motives are discussed. Needed areas for future research are described.

  20. Memory for Pictorial Information and the Picture Superiority Effect.

    ERIC Educational Resources Information Center

    Maisto, Albert A.; Queen, Debbie Elaine

    1992-01-01

    The performance of 53 younger adults (mean age 20.7) and 52 older adults (mean age 68.3) was compared in a memory task involving pictures, words, and pictures-plus-words. Results showed (1) significantly higher recall scores for younger adults; (2) equivalent picture superiority effect for both groups; and (3) decline in older adults' performance…

  1. A Developmental, Interactive Activation Model of the Word Superiority Effect.

    ERIC Educational Resources Information Center

    Chase, Christopher H.; Tallal, Paula

    1990-01-01

    Examined effects of orthographic context on the letter recognition skills of dyslexic children, comparing their performance to that of adults and of chronological and reading age-matched groups. Results showed that the two matched groups showed strong word superiority effect (WSE) for words and pseudowords over nonwords. Dyslexic readers did not…

  2. Why Is Visual Search Superior in Autism Spectrum Disorder?

    ERIC Educational Resources Information Center

    Joseph, Robert M.; Keehn, Brandon; Connolly, Christine; Wolfe, Jeremy M.; Horowitz, Todd S.

    2009-01-01

    This study investigated the possibility that enhanced memory for rejected distractor locations underlies the superior visual search skills exhibited by individuals with autism spectrum disorder (ASD). We compared the performance of 21 children with ASD and 21 age- and IQ-matched typically developing (TD) children in a standard static search task…

  3. Imaging Evaluation of Superior Labral Anteroposterior (SLAP) Tears.

    PubMed

    Grubin, Jeremy; Maderazo, Alex; Fitzpatrick, Darren

    2015-10-01

    Superior labral anteroposterior (SLAP) tears are common injuries that are best evaluated with magnetic resonance arthrography (MRA), as it provides the most detailed evaluation of the bicipital labral complex. Given the variety and complexity of SLAP tears, distention of the joint with intra-articular dilute gadolinium contrast properly separates the intra-articular biceps tendon, superior labrum, glenoid cartilage and glenohumeral ligaments to optimize assessment of these structures. This allows for increased diagnostic confidence of the interpreting radiologist and provides a better road map for the surgeon prior to arthroscopy. Indirect MRA and high-field magnetic resonance imaging are sensitive and specific alternative modalities if MRA cannot be performed.

  4. Transradial approach for transcatheter selective superior mesenteric artery urokinase infusion therapy in patients with acute extensive portal and superior mesenteric vein thrombosis.

    PubMed

    Wang, Mao Qiang; Guo, Li Ping; Lin, Han Ying; Liu, Feng Yong; Duan, Feng; Wang, Zhi Jun

    2010-02-01

    The purpose of this investigation was to assess the feasibility and effectiveness of transradial approach for transcatheter superior mesenteric artery (SMA) urokinase infusion therapy in patients with acute extensive portal and superior mesenteric venous thrombosis. During a period of 7 years, 16 patients with acute extensive thrombosis of the portal (PV) and superior mesenteric veins (SMV) were treated by transcatheter selective SMA urokinase infusion therapy by way of the radial artery. The mean age of the patients was 39.5 years. Through the radial sheath, a 5F Cobra catheter was inserted into the SMA, and continuous infusion of urokinase was performed for 5-11 days (7.1 +/- 2.5 days). Adequate anticoagulation was given during treatment, throughout hospitalization, and after discharge. Technical success was achieved in all 16 patients. Substantial clinical improvement was seen in these 16 patients after the procedure. Minor complications at the radial puncture site were observed in 5 patients, but trans-SMA infusion therapy was not interrupted. Follow-up computed tomography scan before discharge demonstrated nearly complete disappearance of PV-SMV thrombosis in 9 patients and partial recanalization of PV-SMV thrombosis in 7 patients. The 16 patients were discharged 9-19 days (12 +/- 6.0 days) after admission. Mean duration of follow-up after hospital discharge was 44 +/- 18.5 months, and no recurrent episodes of PV-SMV thrombosis developed during that time period. Transradial approach for transcatheter selective SMA urokinase infusion therapy in addition to anticoagulation is a safe and effective therapy for the management of patients with acute extensive PV-SMV thrombosis.

  5. Transradial Approach for Transcatheter Selective Superior Mesenteric Artery Urokinase Infusion Therapy in Patients with Acute Extensive Portal and Superior Mesenteric Vein Thrombosis

    SciTech Connect

    Wang Maoqiang Guo Liping; Lin Hanying; Liu Fengyong; Duan Feng; Wang Zhijun

    2010-02-15

    The purpose of this investigation was to assess the feasibility and effectiveness of transradial approach for transcatheter superior mesenteric artery (SMA) urokinase infusion therapy in patients with acute extensive portal and superior mesenteric venous thrombosis. During a period of 7 years, 16 patients with acute extensive thrombosis of the portal (PV) and superior mesenteric veins (SMV) were treated by transcatheter selective SMA urokinase infusion therapy by way of the radial artery. The mean age of the patients was 39.5 years. Through the radial sheath, a 5F Cobra catheter was inserted into the SMA, and continuous infusion of urokinase was performed for 5-11 days (7.1 {+-} 2.5 days). Adequate anticoagulation was given during treatment, throughout hospitalization, and after discharge. Technical success was achieved in all 16 patients. Substantial clinical improvement was seen in these 16 patients after the procedure. Minor complications at the radial puncture site were observed in 5 patients, but trans-SMA infusion therapy was not interrupted. Follow-up computed tomography scan before discharge demonstrated nearly complete disappearance of PV-SMV thrombosis in 9 patients and partial recanalization of PV-SMV thrombosis in 7 patients. The 16 patients were discharged 9-19 days (12 {+-} 6.0 days) after admission. Mean duration of follow-up after hospital discharge was 44 {+-} 18.5 months, and no recurrent episodes of PV-SMV thrombosis developed during that time period. Transradial approach for transcatheter selective SMA urokinase infusion therapy in addition to anticoagulation is a safe and effective therapy for the management of patients with acute extensive PV-SMV thrombosis.

  6. Students' Accounts of School-Performance Stress: A Qualitative Analysis of a High-Achieving Setting in Stockholm, Sweden

    ERIC Educational Resources Information Center

    Låftman, Sara Brolin; Almquist, Ylva B.; Östberg, Viveca

    2013-01-01

    The aim of the study is to examine students' experiences of school performance as a stressor. Accounts of school-performance stress at both the individual level and in relation to group mechanisms are studied through qualitative interviews with eighth-grade students in a high-performing school in Stockholm, Sweden (n = 49). Using qualitative…

  7. Evaluation of the Effects of Medium of Instruction on the Science Learning of Hong Kong Secondary Students: Performance on the Science Achievement Test.

    ERIC Educational Resources Information Center

    Yip, Din Yan; Tsang, Wing Kwong; Cheung, Sin Pui

    2003-01-01

    A study examined the effects of a new Hong Kong policy requiring Chinese as the language of instruction on secondary students' learning of science. Science achievement test scores at 100 secondary schools indicate that previous use of English to teach science may have hampered students' ability to grasp material due to the high-level thinking…

  8. Are Physical Activity and Academic Performance Compatible? Academic Achievement, Conduct, Physical Activity and Self-Esteem of Hong Kong Chinese Primary School Children

    ERIC Educational Resources Information Center

    Yu, C. C. W.; Chan, Scarlet; Cheng, Frances; Sung, R. Y. T.; Hau, Kit-Tai

    2006-01-01

    Education is so strongly emphasized in the Chinese culture that academic success is widely regarded as the only indicator of success, while too much physical activity is often discouraged because it drains energy and affects academic concentration. This study investigated the relations among academic achievement, self-esteem, school conduct and…

  9. Achieving Teacher Education Standards through a Mathematics Performance-Based Assessment: A Case Study of Five Colorado Preservice-Teachers on Field Experience

    ERIC Educational Resources Information Center

    Clark, Julie

    2005-01-01

    A range of factors has impinged on the provision of teacher education programs in the last decade. Largely emanating from governmental demands for increased accountability, these have included the setting of standards for student achievement, proof of program impact, and state and national testing. These legislative reforms and school district…

  10. Feelings and Performance in the First Year at University: Learning-Related Emotions as Predictors of Achievement Outcomes in Mathematics and Statistics

    ERIC Educational Resources Information Center

    Niculescu, Alexandra C.; Templelaar, Dirk; Leppink, Jimmie; Dailey-Hebert, Amber; Segers, Mien; Gijselaers, Wim

    2015-01-01

    Introduction: This study examined the predictive value of four learning-related emotions--Enjoyment, Anxiety, Boredom and Hopelessness for achievement outcomes in the first year of study at university. Method: We used a large sample (N = 2337) of first year university students enrolled over three consecutive academic years in a mathematics and…

  11. Autonomy Support and Achievement Goals as Predictors of Perceived School Performance and Life Satisfaction in the Transition between Lower and Upper Secondary School

    ERIC Educational Resources Information Center

    Diseth, Åge; Samdal, Oddrun

    2014-01-01

    A self-determination theory perspective on motivation assumes that basic need support is a prerequisite for motivation, achievement, and well-being in several domains of life. In the present cross-sectional study, a representative sample of 2.594 Norwegian students in their final year of lower secondary education and their first year of upper…

  12. Achieving Professional Excellence: Proceedings of a National Conference on Performance-Based Approaches to Training (Little Rock, Arkansas, October 8-10, 1985).

    ERIC Educational Resources Information Center

    Harrington, Lois G., Comp.; Kalamas, David J., Comp.

    This document contains 47 presentations which focus on professional preparation of personnel in vocational-technical education and industry as an essential step in achieving excellence in educational and industrial training programs. The presentations include "Critical Issues Facing Vocational Teacher Education" (Zellner, Parrish); "A Call for…

  13. Keeping Your Kids Out Front without Kicking Them from Behind: How To Nurture High-Achieving Athletes, Scholars, and Performing Artists.

    ERIC Educational Resources Information Center

    Tofler, Ian; DiGeronimo, Theresa Foy

    Pressuring gifted children into achieving parents' own unfulfilled longings for glory and success can cheat children of a normal childhood. This commonsense guide for parents of talented and gifted children offers guidance for establishing healthy boundaries between parents' ambitions and the needs of their talented children and provides clear-cut…

  14. Testing a Multi-Stage Screening System: Predicting Performance on Australia's National Achievement Test Using Teachers' Ratings of Academic and Social Behaviors

    ERIC Educational Resources Information Center

    Kettler, Ryan J.; Elliott, Stephen N.; Davies, Michael; Griffin, Patrick

    2012-01-01

    This study addresses the predictive validity of results from a screening system of academic enablers, with a sample of Australian elementary school students, when the criterion variable is end-of-year achievement. The investigation included (a) comparing the predictive validity of a brief criterion-referenced nomination system with more…

  15. The Impact of Nursing Students' Chemistry Learning Performance Assessment in Taiwan: Competitive versus Non-Competitive Student Team Achievement Division Approaches

    ERIC Educational Resources Information Center

    Wang, Kai-Ping

    2012-01-01

    Purpose: The purpose of this study was to determine the effectiveness of competitive Student Team Achievement Division (STAD), non-competitive STAD, and traditional learning on chemistry learning and learning perceptions. Sample, design and methods: By adopting the STAD approach, this study examined 144 nursing students at a five-year junior…

  16. High Performing Schools in High Risk Environments: A Study on Leadership, School Safety, and Student Achievement at Two Urban Middle Schools in Los Angeles County

    ERIC Educational Resources Information Center

    Frias, Gus

    2010-01-01

    In the United States of America, all students and staff have a constitutional right to attend schools that are safe, secure, and successful. Despite this right, at many public schools, education leaders have failed to ensure the safety and high academic achievement of all students. The purpose of this research study is to expand knowledge about…

  17. Rehearsal Characteristics of "Superior" Band Directors

    ERIC Educational Resources Information Center

    Juchniewicz, Jay; Kelly, Steven N.; Acklin, Amy I.

    2014-01-01

    The purpose of this study was to investigate the rehearsal characteristics of "superior" middle and high school band directors. A total of 131 respondents from Florida, Kentucky, and North Carolina who received a "superior" rating for 4 out of the past 5 years, completed an open-ended essay question online asking them to…

  18. STATUS OF MYSIS RELICTA IN LAKE SUPERIOR

    EPA Science Inventory

    The status of different components of the lower food web is reported for Lake Superior. Results are preliminary summaries from the Binational collaboration in 2005, which measured the lower food web at the request of the Lake Superior Fisheries Technical Committee and Lake Superi...

  19. Remodelling of the Superior Caval Vein After Angioplasty in an Infant with Superior Caval Vein Syndrome

    SciTech Connect

    Mert, Murat Saltik, Levent; Gunay, Ilhan

    2004-08-15

    An 8-month old girl was presented with superior caval vein syndrome early after cardiac surgery. Angiography showed severe stenosis of the superior caval vein with 50 mmHg pressure gradient. Following balloon angioplasty, the pressure gradient was reduced to 7 mmHg with some residual stenosis of the superior caval vein. When the patient was reevaluated 5 months after the procedure, angiography revealed a normal diameter of the superior caval vein without a pressure gradient.

  20. AlF 3 Surface-Coated Li[Li 0.2 Ni 0.17 Co 0.07 Mn 0.56 ]O 2 Nanoparticles with Superior Electrochemical Performance for Lithium-Ion Batteries

    DOE PAGES

    Sun, Shuwei; Yin, Yanfeng; Wan, Ning; Wu, Qing; Zhang, Xiaoping; Pan, Du; Bai, Ying; Lu, Xia

    2015-06-24

    For Li-rich layered cathode materials considerable attention has been paid owing to their high capacity performance for Li-ion batteries (LIBs). In our work, layered Li-rich Li[Li0.2Ni0.17Co0.07Mn0.56]O2 nanoparticles are surface-modified with AlF3 through a facile chemical deposition method. The AlF3 surface layers have little impact on the structure of the material and act as buffers to prevent the direct contact of the electrode with the electrolyte; thus, they enhance the electrochemical performance significantly. The 3 wt% AlF3-coated Li-rich electrode exhibits the best cycling capability and has a considerably enhanced capacity retention of 83.1% after 50 cycles. Moreover, the rate performance andmore » thermal stability of the 3 wt% AlF3-coated electrode are also clearly improved. Finally, surface analysis indicates that the AlF3 coating layer can largely suppress the undesirable growth of solid electrolyte interphase (SEI) film and, therefore, stabilizes the structure upon cycling.« less

  1. 1974-75 Philadelphia City-Wide Testing Program; February 1975 Achievement Testing Program. School Performance Distributions: Kindergarten through Grade Twelve.

    ERIC Educational Resources Information Center

    Grosswald, Jules

    This is a report of pupil performance in Philadelphia schools based upon the February 1975 Philadelphia City-Wide Testing Program involving all pupils in kindergarten through grade 12. School performance distributions show the combined percentages of pupils in each school scoring within various national percentile rank ranges. The performance…

  2. Improving Teacher Effectiveness: An Examination of a Pay for Performance Plan for Boosting Student Academic Achievement in Charlotte-Mecklenburg Schools

    ERIC Educational Resources Information Center

    Ngoma, Sylvester

    2011-01-01

    Throughout the United States, educational organizations are striving to find more effective ways to improve teacher performance and student learning. The increased pressure to improve teacher effectiveness in the classroom has led many public school districts to adopt a pay for performance system as a strategic compensation option for enhancing…

  3. Laparoscopic Pancreaticoduodenectomy: Right Posterior Superior Mesenteric Artery "First" Approach.

    PubMed

    Pittau, Gabriella; Sànchez-Cabùs, Santiago; Laurenzi, Andrea; Gelli, Maximiliano; Cunha, Antonio Sa

    2015-12-01

    Pancreaticoduodenectomy (PD) is considered one of the most challenging abdominal operations for several reasons, including the anatomy, which is surrounded by vital vascular structures and also because of the serious complications that are possible in the postoperative period. Nowadays, thanks to the development of minimally invasive surgery and improvement of patients' selection, laparoscopic pancreatic resections have been proven to be technically feasible and safe especially in the case of left pancreatectomies. More recently, many series of laparoscopic PD for adenocarcinoma have been published demonstrating the feasibility of this technique. In pancreatic cancer, the advantage of superior mesenteric artery "first approach" is already known to achieve an oncological resection. The purpose of this video is to describe the different technical aspects of the laparoscopic superior mesenteric artery first approach in the right posterior fashion.

  4. Superior metallic alloys through rapid solidification processing (RSP) by design

    SciTech Connect

    Flinn, J.E.

    1995-05-01

    Rapid solidification processing using powder atomization methods and the control of minor elements such as oxygen, nitrogen, and carbon can provide metallic alloys with superior properties and performance compared to conventionally processing alloys. Previous studies on nickel- and iron-base superalloys have provided the baseline information to properly couple RSP with alloy composition, and, therefore, enable alloys to be designed for performance improvements. The RSP approach produces powders, which need to be consolidated into suitable monolithic forms. This normally involves canning, consolidation, and decanning of the powders. Canning/decanning is expensive and raises the fabrication cost significantly above that of conventional, ingot metallurgy production methods. The cost differential can be offset by the superior performance of the RSP metallic alloys. However, without the performance database, it is difficult to convince potential users to adopt the RSP approach. Spray casting of the atomized molten droplets into suitable preforms for subsequent fabrication can be cost competitive with conventional processing. If the fine and stable microstructural features observed for the RSP approach are preserved during spray casing, a cost competitive product can be obtained that has superior properties and performance that cannot be obtained by conventional methods.

  5. Carbonates-based noble metal-free lean NOx trap catalysts MOx-K2CO3/K2Ti8O17 (M = Ce, Fe, Cu, Co) with superior catalytic performance

    NASA Astrophysics Data System (ADS)

    Zhang, Yuxia; You, Rui; Liu, Dongsheng; Liu, Cheng; Li, Xingang; Tian, Ye; Jiang, Zheng; Zhang, Shuo; Huang, Yuying; Zha, Yuqing; Meng, Ming

    2015-12-01

    A series of base metal-based lean NOx trap (LNT) catalysts MOx-K2CO3/K2Ti8O17 (M = Ce, Fe, Cu, Co) were synthesized by successive impregnations and employed for the storage and reduction of NOx in the emissions of lean-burn engines at 350 °C. The XRD and XANES/EXAFS results reveal that the active phases in the corresponding catalysts exist as CeO2, Fe2O3, CuO and Co3O4, respectively. Among all the catalysts, CoOx-K2CO3/K2Ti8O17 exhibits the best performance, which cannot only trap the NOx quickly and completely at lean condition, giving the highest storage capacity (3.32 mmol/g) reported so far, but also reduce the NOx at rich condition, showing a NOx reduction percentage as high as 99.0%. Meanwhile, this catalyst displays an ultralow NOx to N2O selectivity (0.3%) during NOx reduction. The excellent performance of CoOx-K2CO3/K2Ti8O17 results from its largest amount of surface active oxygen species as revealed by XPS, O2-TPD and NO-TPD. HRTEM, FT-IR and CO2-TPD results illustrate that several kinds of K species such as sbnd OK groups, K2O, surface carbonates and bulk or bulk-like carbonates coexist in the catalysts. Based upon the in situ DRIFTS results, the participation of K2CO3 in NOx storage is confirmed, and the predominant NOx storage species is revealed as bidentate nitrites formed via multiple kinetic pathways. The low cost and high catalytic performance of the CoOx-based LNT catalyst make it most promising for the substitution of noble metal-based LNT catalysts.

  6. Which Feedback Is More Effective for Pursuing Multiple Goals of Differing Importance? The Interaction Effects of Goal Importance and Performance Feedback Type on Self-Regulation and Task Achievement

    ERIC Educational Resources Information Center

    Lee, Hyunjoo

    2016-01-01

    This study examined how performance feedback type (progress vs. distance) affects Korean college students' self-regulation and task achievement according to relative goal importance in the pursuit of multiple goals. For this study, 146 students participated in a computerised task. The results showed the interaction effects of goal importance and…

  7. WWC Review of the Report "Closing the Social-Class Achievement Gap: A Difference-Education Intervention Improves First-Generation Students' Academic Performance and All Students' College Transition." What Works Clearinghouse Single Study Review

    ERIC Educational Resources Information Center

    What Works Clearinghouse, 2014

    2014-01-01

    For the 2014 study, "Closing the Social-Class Achievement Gap: A Difference-Education Intervention Improves First-Generation Students' Academic Performance and All Students' College Transition," researchers investigated the impact of attending a moderated panel on incoming freshmen's adjustment to college. The panel…

  8. Carbon phosphide monolayers with superior carrier mobility.

    PubMed

    Wang, Gaoxue; Pandey, Ravindra; Karna, Shashi P

    2016-04-28

    Two dimensional (2D) materials with a finite band gap and high carrier mobility are sought after materials from both fundamental and technological perspectives. In this paper, we present the results based on the particle swarm optimization method and density functional theory which predict three geometrically different phases of the carbon phosphide (CP) monolayer consisting of sp2 hybridized C atoms and sp3 hybridized P atoms in hexagonal networks. Two of the phases, referred to as α-CP and β-CP with puckered or buckled surfaces are semiconducting with highly anisotropic electronic and mechanical properties. More remarkably, they have the lightest electrons and holes among the known 2D semiconductors, yielding superior carrier mobility. The γ-CP has a distorted hexagonal network and exhibits a semi-metallic behavior with Dirac cones. These theoretical findings suggest that the binary CP monolayer is a yet unexplored 2D material holding great promise for applications in high-performance electronics and optoelectronics. PMID:27067002

  9. Morphological characteristics of the superior cerebellar artery.

    PubMed

    Dodevski, A; Tosovska Lazarova, D; Zhivadinovik, J; Lazareska, M; Stojovska-Jovanovska, E

    2015-01-01

    With the introduction of new techniques in diagnostic and interventional radiology and progress in micro neurosurgery, accurate knowledge of the brain blood vessels is essential for daily clinical work. The aim of this study was to describe the morphological characteristics of the superior cerebellar artery and to emphasize their clinical significance. In this study we examined radiographs of 109 patients who had CT angiography at the University Clinic for Radiology in Skopje, R. Macedonia. This study included 49 females and 60 males, ranging in age from 27 to 83 years; mean age 57.4 ± 11.8 years. In 105 patients SCA arose from the basilar artery on both sides as a single vessel. In two patients SCA arose as a duplicate trunk from the basilar artery. We found unilateral duplication on the right SCA in one patient, and bilateral duplication in one patient. In two patients was noticed origin of the SCA from PCA as a single trunk from adult type of the PCA. Through knowledge of the anatomy and variations of SCA is important for clinicians as well as basic scientists who deal with problems related to intracranial vasculature in daily basis for save performance of diagnostic and interventional procedures. PMID:26076777

  10. Morphological characteristics of the superior cerebellar artery.

    PubMed

    Dodevski, A; Tosovska Lazarova, D; Zhivadinovik, J; Lazareska, M; Stojovska-Jovanovska, E

    2015-01-01

    With the introduction of new techniques in diagnostic and interventional radiology and progress in micro neurosurgery, accurate knowledge of the brain blood vessels is essential for daily clinical work. The aim of this study was to describe the morphological characteristics of the superior cerebellar artery and to emphasize their clinical significance. In this study we examined radiographs of 109 patients who had CT angiography at the University Clinic for Radiology in Skopje, R. Macedonia. This study included 49 females and 60 males, ranging in age from 27 to 83 years; mean age 57.4 ± 11.8 years. In 105 patients SCA arose from the basilar artery on both sides as a single vessel. In two patients SCA arose as a duplicate trunk from the basilar artery. We found unilateral duplication on the right SCA in one patient, and bilateral duplication in one patient. In two patients was noticed origin of the SCA from PCA as a single trunk from adult type of the PCA. Through knowledge of the anatomy and variations of SCA is important for clinicians as well as basic scientists who deal with problems related to intracranial vasculature in daily basis for save performance of diagnostic and interventional procedures.

  11. Achieving ICME with Multiscale Modeling: The Effects of Constituent Properties and Processing on the Performance of Laminated Polymer Matrix Composite Structures

    NASA Technical Reports Server (NTRS)

    Pineda, Evan Jorge; Bednarcyk, Brett A.; Arnold, Steven M.

    2014-01-01

    Integrated computational materials engineering (ICME) is a useful approach for tailoring the performance of a material. For fiber-reinforced composites, not only do the properties of the constituents of the composite affect the performance, but so does the architecture (or microstructure) of the constituents. The generalized method of cells is demonstrated to be a viable micromechanics tool for determining the effects of the microstructure on the performance of laminates. The micromechanics is used to predict the inputs for a macroscale model for a variety of different fiber volume fractions, and fiber architectures. Using this technique, the material performance can be tailored for specific applications by judicious selection of constituents, volume fraction, and architectural arrangement given a particular manufacturing scenario

  12. Closing the social-class achievement gap: a difference-education intervention improves first-generation students' academic performance and all students' college transition.

    PubMed

    Stephens, Nicole M; Hamedani, MarYam G; Destin, Mesmin

    2014-04-01

    College students who do not have parents with 4-year degrees (first-generation students) earn lower grades and encounter more obstacles to success than do students who have at least one parent with a 4-year degree (continuing-generation students). In the study reported here, we tested a novel intervention designed to reduce this social-class achievement gap with a randomized controlled trial (N = 168). Using senior college students' real-life stories, we conducted a difference-education intervention with incoming students about how their diverse backgrounds can shape what they experience in college. Compared with a standard intervention that provided similar stories of college adjustment without highlighting students' different backgrounds, the difference-education intervention eliminated the social-class achievement gap by increasing first-generation students' tendency to seek out college resources (e.g., meeting with professors) and, in turn, improving their end-of-year grade point averages. The difference-education intervention also improved the college transition for all students on numerous psychosocial outcomes (e.g., mental health and engagement).

  13. Is There a Limit to the Superiority of Individuals with ASD in Visual Search?

    ERIC Educational Resources Information Center

    Hessels, Roy S.; Hooge, Ignace T. C.; Snijders, Tineke M.; Kemner, Chantal

    2014-01-01

    Superiority in visual search for individuals diagnosed with autism spectrum disorder (ASD) is a well-reported finding. We administered two visual search tasks to individuals with ASD and matched controls. One showed no difference between the groups, and one did show the expected superior performance for individuals with ASD. These results offer an…

  14. Superior temporal gyrus, language function, and autism.

    PubMed

    Bigler, Erin D; Mortensen, Sherstin; Neeley, E Shannon; Ozonoff, Sally; Krasny, Lori; Johnson, Michael; Lu, Jeffrey; Provencal, Sherri L; McMahon, William; Lainhart, Janet E

    2007-01-01

    Deficits in language are a core feature of autism. The superior temporal gyrus (STG) is involved in auditory processing, including language, but also has been implicated as a critical structure in social cognition. It was hypothesized that subjects with autism would display different size-function relationships between the STG and intellectual-language-based abilities when compared to controls. Intellectual ability was assessed by either the Wechsler Intelligence Scale for Children-Third Edition (WISC-III) or Wechsler Adult Intelligence Scale-Third Edition (WAIS-III), where three intellectual quotients (IQ) were computed: verbal (VIQ), performance (PIQ), and full-scale (FSIQ). Language ability was assessed by the Clinical Evaluation of Language Fundamentals-Third Edition (CELF-3), also divided into three index scores: receptive, expressive, and total. Seven to 19-year-old rigorously diagnosed subjects with autism (n = 30) were compared to controls (n = 39; 13 of whom had a deficit in reading) of similar age who were matched on education, PIQ, and head circumference. STG volumes were computed based on 1.5 Tesla magnetic resonance imaging (MRI). IQ and CELF-3 performance were highly interrelated regardless of whether subjects had autism or were controls. Both IQ and CELF-3 ability were positively correlated with STG in controls, but a different pattern was observed in subjects with autism. In controls, left STG gray matter was significantly (r = .42, p < or = .05) related to receptive language on the CELF-3; in contrast, a zero order correlation was found with autism. When plotted by age, potential differences in growth trajectories related to language development associated with STG were observed between controls and those subjects with autism. Taken together, these findings suggest a possible failure in left hemisphere lateralization of language function involving the STG in autism.

  15. The effect of parental education, prior achievement, self-efficacy, goal orientation, and effort on undergraduate science performance of Latinos and Caucasians

    NASA Astrophysics Data System (ADS)

    Stansbury, Sydney Lynn

    Compared with majority students, underrepresented minorities have demonstrated weaker undergraduate science performance. Previous research has attributed the weaker performance to socioeconomic factors that influence poorer precollege preparation. Studies also have found that, compared with majority students, underrepresented minorities are less confident about their science skills and more interested in extrinsic rewards of science careers. Social Cognitive Theory posits that low self-efficacy coupled with high extrinsic goal orientation diminishes cognitive engagement, resulting in weak performance. Applying motivational characteristics of underrepresented minority students to a Social Cognitive Model may explain why their performance is weaker than that of Caucasians. Thus, the purpose of this study was to investigate the degree to which motivation variables account for the difference between underrepresented minority and majority students' undergraduate science performance. The study was conducted at a large, predominantly Caucasian, private university located in an urban setting in the Southwest. Two hundred twenty-two students--154 Caucasians and 68 Latinos--enrolled in a general chemistry course participated. Students were administered the Motivation for Learning Questionnaire, designed specifically for this study, consisting of scales measuring the following variables: ethnicity, level of parental education, and effort exertion; self-efficacy, effort regulation, intrinsic goal orientation, and extrinsic goal orientation, measures from the Motivated Strategies for Learning Questionnaire (Pintrich, Smith, Garcia, & McKeachie, 1991); and ability orientation, a measure from the Patterns of Adaptive Learning Survey (Midgley, Maehr, & Urdan, 1995). Financial aid information, chemistry and math placement test scores, and chemistry grades were obtained from other on-campus departments. Results demonstrated that the hypotheses were only partially confirmed by the

  16. Achieving high performance non-fullerene organic solar cells through tuning the numbers of electron deficient building blocks of molecular acceptors

    NASA Astrophysics Data System (ADS)

    Yang, Lei; Chen, Yusheng; Chen, Shangshang; Dong, Tao; Deng, Wei; Lv, Lei; Yang, Saina; Yan, He; Huang, Hui

    2016-08-01

    Two analogous dimer and tetramer compounds, SF-PDI2 and SF-PDI4, were designed, theoretically calculated, synthesized, and developed as electron acceptors for organic solar cells. The effects of the number of the electron deficient building blocks on the optical absorption, energy levels, charge transport, morphology, crystallinity, and photovoltaic performance of the molecules were investigated. In combination with two different donors, PTB7-Th and PffBT4T-2OD, the results showed that increasing the numbers of PDI building blocks is beneficial to photovoltaic performance and leads to efficiency over 5%.

  17. Antegrade rheolytic thrombectomy and thrombolysis for superior sagittal sinus thrombosis using burr hole access

    PubMed Central

    Lee, Darrin J; Latchaw, Richard E; Dahlin, Brian C; Dong, Paul R; Verro, Piero; Muizelaar, J Paul; Shahlaie, Kiarash

    2014-01-01

    Superior sagittal sinus (SSS) thrombosis has high morbidity and mortality, and urgent recanalization is critical for severe cases. Standard endovascular techniques for thrombolysis and thrombectomy use retrograde venous access, an approach that may be unsuccessful in cases with extensive firm clot burden involving the dural sinuses distal to the SSS. An anterior open transcranial approach to the SSS for catheter sheath placement to facilitate antegrade mechanical thrombectomy and thrombolysis of the SSS and more distal sinuses has not been previously described. Here we describe a case in which multiple unsuccessful attempts at retrograde endovascular access were attempted. Thus, a burr hole over the anterior SSS was performed for daily endovascular antegrade procedures using the Angiojet rheolytic catheter device and chemical thrombolysis. Near-complete recanalization of the SSS was achieved with venous outflow via dilated left transverse and left sigmoid sinuses, along with significant collateral flow in multiple cerebral veins. PMID:24692369

  18. An Investigation of Linguistic, Cognitive, and Affective Factors that Impact English Language Learners' Performance on a State Standardized Reading Achievement Test

    ERIC Educational Resources Information Center

    Strebel Halpern, Carine S.

    2009-01-01

    The explicit teaching of reading comprehension strategies has been proposed as a means to better prepare secondary school-aged students for today's information-dense, fast-paced, fast-changing global society, and to improve the academic performance of struggling adolescent readers. This proposition of a direct and positive impact of reading…

  19. Good and Bad News about Florida Student Achievement: Performance Trends on Multiple Indicators Since Passage of the A+ Legislation. Policy Brief.

    ERIC Educational Resources Information Center

    Chatterji, Madhabi

    2004-01-01

    What is the news on Florida's student performance since the passage of the A+ legislation? This brief presents a review of long-term data on five state and national indicators. It verifies outcomes and trends and examines the main premise of the A+ mandate that, given appropriate schooling, students will have equitable outcomes and access to…

  20. The Effects of Cognitive Training on Private Speech and Task Performance during Problem Solving among Learning Disabled and Normally Achieving Children.

    ERIC Educational Resources Information Center

    Harris, Karen R.

    To investigate task performance and the use of private speech and to examine the effects of a cognitive training approach, 30 learning disabled (LD) and 30 nonLD Ss (7 to 8 years old) were given a 17 piece wooden puzzle rigged so that it could not be completed correctly. Six variables were measured: (1) proportion of private speech that was task…

  1. The Effect of Evaluation on Performance: Evidence from Longitudinal Student Achievement Data of Mid-Career Teachers. NBER Working Paper No. 16877

    ERIC Educational Resources Information Center

    Taylor, Eric S.; Tyler, John H.

    2011-01-01

    The effect of evaluation on employee performance is traditionally studied in the context of the principal-agent problem. Evaluation can, however, also be characterized as an investment in the evaluated employee's human capital. We study a sample of mid-career public school teachers where we can consider these two types of evaluation effect…

  2. Are Academic Discounting and Devaluing Double-Edged Swords? Their Relations to Global Self-Esteem, Achievement Goals, and Performance among Stigmatized Students

    ERIC Educational Resources Information Center

    Loose, Florence; Regner, Isabelle; Morin, Alexandre J. S.; Dumas, Florence

    2012-01-01

    Often taken for granted, the coexistence of benefits and costs of discounting and devaluing has never been tested. Yet, not only are there inconsistent findings about the relations between these processes and global self-esteem, but little is known about their relations to motivation and performance. Here we simultaneously examined how academic…

  3. A Comparative Case Study of Veteran Superintendent's Leadership and Organizational Processes in Addressing the Academic Achievement of Students in Low Performing School Districts

    ERIC Educational Resources Information Center

    Reimer, Catherine Nicole

    2010-01-01

    This research study investigated the leadership behaviors and organizational frames utilized by two veteran superintendents of medium sized school districts in California to address issues of academic performance in their respective districts as perceived by the superintendents and their respective board members and principals. Current…

  4. Polyimide Foams Offer Superior Insulation

    NASA Technical Reports Server (NTRS)

    2012-01-01

    At Langley Research Center, Erik Weiser and his colleagues in the Advanced Materials and Processing Branch were working with a new substance for fabricating composites for use in supersonic aircraft. The team, however, was experiencing some frustration. Every time they tried to create a solid composite from the polyimide (an advanced polymer) material, it bubbled and foamed. It seemed like the team had reached a dead end in their research - until they had another idea. "We said, This isn t going to work for composites, but maybe we could make a foam out of it," Weiser says. "That was kind of our eureka moment, to see if we could go in a whole other direction. And it worked." Weiser and his colleagues invented a new kind of polyimide foam insulation they named TEEK. The innovation displayed a host of advantages over existing insulation options. Compared to other commercial foams, Weiser explains, polyimide foams perform well across a broad range of temperatures, noting that the NASA TEEK foams provide effective structural insulation up to 600 F and down to cryogenic temperatures. The foam does not burn or off-gas toxic fumes, and even at -423 F - the temperature of liquid hydrogen - the material stays flexible. The inventors could produce the TEEK foam at a range of densities, from 0.5 pounds per cubic foot up to 20 pounds per cubic foot, making the foam ideal for a range of applications, including as insulation for reusable launch vehicles and for cryogenic tanks and lines. They also developed a unique, friable balloon format for manufacturing the foam, producing it as hollow microspheres that allowed the foam to be molded and then cured into any desired shape - perfect for insulating pipes of different sizes and configurations. The team s originally unplanned invention won an "R&D 100" award, and a later form of the foam, called LaRC FPF-44 (Spinoff 2009), was named "NASA Invention of the Year" in 2007.

  5. Graded Achievement, Tested Achievement, and Validity

    ERIC Educational Resources Information Center

    Brookhart, Susan M.

    2015-01-01

    Twenty-eight studies of grades, over a century, were reviewed using the argument-based approach to validity suggested by Kane as a theoretical framework. The review draws conclusions about the meaning of graded achievement, its relation to tested achievement, and changes in the construct of graded achievement over time. "Graded…

  6. Acute Superior Mesenteric Venous Thrombosis: Transcatheter Thrombolysis and Aspiration Thrombectomy Therapy by Combined Route of Superior Mesenteric Vein and Artery in Eight Patients

    SciTech Connect

    Yang, Shuofei Liu, Baochen Ding, Weiwei He, Changsheng Wu, Xingjiang Li, Jieshou

    2015-02-15

    PurposeTo assess the feasibility, effectiveness, and safety of catheter-directed thrombolysis and aspiration thrombectomy therapy by combined route of superior mesenteric vein and artery (SMV+SMA) for acute superior mesenteric venous thrombosis (ASMVT).MethodsThis retrospective study reviewed eight ASMVT patients with transcatheter direct thrombolysis and aspiration thrombectomy therapy via SMV and indirect thrombolysis via SMA during a period of 14 months. The demographics, etiology, risk factors, therapeutic effect, complications, mortality, and follow-up of the study population were assessed. Anatomic and imaging classification of location and extent of thrombus at diagnosis and degree of thrombus lysis were described.ResultsTechnical success was achieved with substantial improvement in symptoms and thrombus resolution after thrombolytic therapy in all patients. The local urokinase infusion by SMA and SMV was performed for 5–7 (6.13 ± 0.83) and 7–15 (12 ± 2.51) days. Anticoagulation was performed catheter-directed and then orally throughout hospitalization and after discharge. Four patients required delayed localized bowel resection after thrombolytic therapy with no death. Thrombolytic therapy was not interrupted despite minor bleeding at the puncture site in two patients and sepsis in another two postoperatively. Nearly complete removal of thrombus was demonstrated by contrast-enhanced CT scan and portography before discharge. Patients were discharged in 10–27 (19.25 ± 4.89) days after admission. No recurrence developed during the follow-up of 10–13 (12.13 ± 0.99) months.ConclusionsCatheter-directed thrombolytic and aspiration therapy via SMV+SMA is beneficial for ASMVT in avoiding patient death, efficient resolving thrombus, rapid improving symptoms, reversing extensive intestinal ischemia, averting bowel resection, or localizing infarcted bowel segment and preventing short bowel syndrome.

  7. Treatment of the Superior Sagittal Sinus Thrombosis with the Mechanical Thrombectomy Using Stent-Retriever Device.

    PubMed

    Kim, Hoon; Kim, Seong Rim; Park, Ik Seong; Kim, Young Woo

    2016-09-01

    Cerebral venous sinus thrombosisis an uncommon entity and its clinical presentations are highly variable. We present the case of superior sagittal sinus thrombosis. Although it was medical refractory, successfully treated with mechanical thrombectomy using the Solitaire FR device. A 27-year-old man who presented with venous infarction accompanied by petechial hemorrhage secondary to the superior sagittal sinus (SSS) thrombosis. Due to rapid deterioration despite of anticoagulation therapy, the patient was taken for endovascular treatment. We deployed the Solitaire FR device (4×20 mm) in the anterior portion of the thrombosed SSS, and it was left for ten minutes before the retraction. Thus, we removed a small amount of thrombus. But the sinus remained occluded. We therefore performed the thrombectomy using the same methods using the Solitaire FR (6×20 mm). Thus, we were successful in removing larger clots. Our case highlights not only that the mechanical thrombectomy using the Solitaire FR is effective in achieving revascularization both rapidly and efficiently available, but also that it might be another option in patients with cerebral venous sinus thrombosis who concurrently had rapid clinical deterioration with devastating consequences.

  8. Treatment of the Superior Sagittal Sinus Thrombosis with the Mechanical Thrombectomy Using Stent-Retriever Device

    PubMed Central

    Kim, Hoon; Kim, Seong Rim; Park, Ik Seong

    2016-01-01

    Cerebral venous sinus thrombosisis an uncommon entity and its clinical presentations are highly variable. We present the case of superior sagittal sinus thrombosis. Although it was medical refractory, successfully treated with mechanical thrombectomy using the Solitaire FR device. A 27-year-old man who presented with venous infarction accompanied by petechial hemorrhage secondary to the superior sagittal sinus (SSS) thrombosis. Due to rapid deterioration despite of anticoagulation therapy, the patient was taken for endovascular treatment. We deployed the Solitaire FR device (4×20 mm) in the anterior portion of the thrombosed SSS, and it was left for ten minutes before the retraction. Thus, we removed a small amount of thrombus. But the sinus remained occluded. We therefore performed the thrombectomy using the same methods using the Solitaire FR (6×20 mm). Thus, we were successful in removing larger clots. Our case highlights not only that the mechanical thrombectomy using the Solitaire FR is effective in achieving revascularization both rapidly and efficiently available, but also that it might be another option in patients with cerebral venous sinus thrombosis who concurrently had rapid clinical deterioration with devastating consequences. PMID:27651872

  9. Treatment of the Superior Sagittal Sinus Thrombosis with the Mechanical Thrombectomy Using Stent-Retriever Device

    PubMed Central

    Kim, Hoon; Kim, Seong Rim; Park, Ik Seong

    2016-01-01

    Cerebral venous sinus thrombosisis an uncommon entity and its clinical presentations are highly variable. We present the case of superior sagittal sinus thrombosis. Although it was medical refractory, successfully treated with mechanical thrombectomy using the Solitaire FR device. A 27-year-old man who presented with venous infarction accompanied by petechial hemorrhage secondary to the superior sagittal sinus (SSS) thrombosis. Due to rapid deterioration despite of anticoagulation therapy, the patient was taken for endovascular treatment. We deployed the Solitaire FR device (4×20 mm) in the anterior portion of the thrombosed SSS, and it was left for ten minutes before the retraction. Thus, we removed a small amount of thrombus. But the sinus remained occluded. We therefore performed the thrombectomy using the same methods using the Solitaire FR (6×20 mm). Thus, we were successful in removing larger clots. Our case highlights not only that the mechanical thrombectomy using the Solitaire FR is effective in achieving revascularization both rapidly and efficiently available, but also that it might be another option in patients with cerebral venous sinus thrombosis who concurrently had rapid clinical deterioration with devastating consequences.

  10. Treatment of the Superior Sagittal Sinus Thrombosis with the Mechanical Thrombectomy Using Stent-Retriever Device.

    PubMed

    Kim, Hoon; Kim, Seong Rim; Park, Ik Seong; Kim, Young Woo

    2016-09-01

    Cerebral venous sinus thrombosisis an uncommon entity and its clinical presentations are highly variable. We present the case of superior sagittal sinus thrombosis. Although it was medical refractory, successfully treated with mechanical thrombectomy using the Solitaire FR device. A 27-year-old man who presented with venous infarction accompanied by petechial hemorrhage secondary to the superior sagittal sinus (SSS) thrombosis. Due to rapid deterioration despite of anticoagulation therapy, the patient was taken for endovascular treatment. We deployed the Solitaire FR device (4×20 mm) in the anterior portion of the thrombosed SSS, and it was left for ten minutes before the retraction. Thus, we removed a small amount of thrombus. But the sinus remained occluded. We therefore performed the thrombectomy using the same methods using the Solitaire FR (6×20 mm). Thus, we were successful in removing larger clots. Our case highlights not only that the mechanical thrombectomy using the Solitaire FR is effective in achieving revascularization both rapidly and efficiently available, but also that it might be another option in patients with cerebral venous sinus thrombosis who concurrently had rapid clinical deterioration with devastating consequences. PMID:27651872

  11. Core-shell heterostructured metal oxide arrays enable superior light-harvesting and hysteresis-free mesoscopic perovskite solar cells

    NASA Astrophysics Data System (ADS)

    Mahmood, Khalid; Swain, Bhabani Sankar; Amassian, Aram

    2015-07-01

    To achieve highly efficient mesoscopic perovskite solar cells (PSCs), the structure and properties of an electron transport layer (ETL) or material (ETM) have been shown to be of supreme importance. Particularly, the core-shell heterostructured mesoscopic ETM architecture has been recognized as a successful electrode design, because of its large internal surface area, superior light-harvesting efficiency and its ability to achieve fast charge transport. Here we report the successful fabrication of a hysteresis-free, 15.3% efficient PSC using vertically aligned ZnO nanorod/TiO2 shell (ZNR/TS) core-shell heterostructured ETMs for the first time. We have also added a conjugated polyelectrolyte polymer into the growth solution to promote the growth of high aspect ratio (AR) ZNRs and substantially improve the infiltration of the perovskite light absorber into the ETM. The PSCs based on the as-synthesized core-shell ZnO/TiO2 heterostructured ETMs exhibited excellent performance enhancement credited to the superior light harvesting capability, larger surface area, prolonged charge-transport pathways and lower recombination rate. The unique ETM design together with minimal hysteresis introduces core-shell ZnO/TiO2 heterostructures as a promising mesoscopic electrode approach for the fabrication of efficient PSCs.To achieve highly efficient mesoscopic perovskite solar cells (PSCs), the structure and properties of an electron transport layer (ETL) or material (ETM) have been shown to be of supreme importance. Particularly, the core-shell heterostructured mesoscopic ETM architecture has been recognized as a successful electrode design, because of its large internal surface area, superior light-harvesting efficiency and its ability to achieve fast charge transport. Here we report the successful fabrication of a hysteresis-free, 15.3% efficient PSC using vertically aligned ZnO nanorod/TiO2 shell (ZNR/TS) core-shell heterostructured ETMs for the first time. We have also added a

  12. Superior thyroid artery origin in Caucasian Greeks: A new classification proposal and review of the literature.

    PubMed

    Natsis, Konstantinos; Raikos, Athanasios; Foundos, Ioannis; Noussios, George; Lazaridis, Nikolaos; Njau, Samouel N

    2011-09-01

    Studies on the origin of the superior thyroid artery, define that it could originate either from the external carotid artery, (at the level of common carotid bifurcation), or from the common carotid artery. However, there is a classical anatomic knowledge that the superior thyroid artery is a branch of the external carotid artery. Variability in the anatomy of the superior thyroid artery was studied on 100 carotids. Moreover, a review about the origin of superior thyroid artery between recent and previous cadaveric, autopsy, and angiographic studies, on adults and fetuses, was carried out. The superior thyroid artery originated from the external carotid artery in 39% and at the level of carotid bifurcation and common carotid artery in 61% of cases. The anterior branches of the external carotid artery were separate in 76% of cases, while common trunks between the arteries were found in 24% of the specimens. A new classification proposal on the origin of the superior thyroid artery is also suggested. In this study, the origin of superior thyroid artery is considered at the level of the carotid bifurcation and not from the external carotid artery as stated in many classical anatomy textbooks. This has a great impact on the terminology when referring to the anterior branches of the external carotid artery, which could be termed as anterior branches of the cervical carotid artery. Head and neck surgeons must be familiar with anatomical variations of the superior thyroid artery in order to achieve a better surgical outcome.

  13. Highly Functional TNTs with Superb Photocatalytic, Optical, and Electronic Performance Achieving Record PV Efficiency of 10.1% for 1D-Based DSSCs.

    PubMed

    Qadir, Muhammad Bilal; Li, Yuewen; Sahito, Iftikhar Ali; Arbab, Alvira Ayoub; Sun, Kyung Chul; Mengal, Naveed; Memon, Anam Ali; Jeong, Sung Hoon

    2016-09-01

    Different nanostructures of TiO2 play an important role in the photocatalytic and photoelectronic applications. TiO2 nanotubes (TNTs) have received increasing attention for these applications due to their unique physicochemical properties. Focusing on highly functional TNTs (HF-TNTs) for photocatalytic and photoelectronic applications, this study describes the facile hydrothermal synthesis of HF-TNTs by using commercial and cheaper materials for cost-effective manufacturing. To prove the functionality and applicability, these TNTs are used as scattering structure in dye-sensitized solar cells (DSSCs). Photocatalytic, optical, Brunauer-Emmett-Teller (BET), electrochemical impedance spectrum, incident-photon-to-current efficiency, and intensity-modulated photocurrent spectroscopy/intensity-modulated photovoltage spectroscopy characterizations are proving the functionality of HF-TNTs for DSSCs. HF-TNTs show 50% higher photocatalytic degradation rate and also 68% higher dye loading ability than conventional TNTs (C-TNTs). The DSSCs having HF-TNT and its composite-based multifunctional overlayer show effective light absorption, outstanding light scattering, lower interfacial resistance, longer electron lifetime, rapid electron transfer, and improved diffusion length, and consequently, J SC , quantum efficiency, and record photoconversion efficiency of 10.1% using commercial N-719 dye is achieved, for 1D-based DSSCs. These new and highly functional TNTs will be a concrete fundamental background toward the development of more functional applications in fuel cells, dye-sensitized solar cells, Li-ion batteries, photocatalysis process, ion-exchange/adsorption process, and photoelectrochemical devices. PMID:27432775

  14. Surgical outcomes of superior versus inferior glaucoma drainage device implantation

    PubMed Central

    Martino, Amy Z.; Iverson, Shawn; Feuer, William J.; Greenfield, David S.

    2013-01-01

    Purpose To compare the safety and intraocular pressure (IOP) lowering efficacy of initial glaucoma drainage device (GDD) implantation performed at the superior versus inferior limbus. Methods A retrospective chart review was conducted to identify glaucoma patients that had undergone initial Baerveldt GDD surgery at the inferior limbus for uncontrolled IOP. All eyes had a minimum of 6 months of postoperative follow-up. These eyes were frequency matched to eyes with initial Baerveldt GDD implantation performed at the superior limbus to within 5 years of age and 6 months of follow-up. Baseline demographic and clinical information, as well as preoperative and postoperative IOP, visual acuity, and number of anti-glaucoma medications were extracted. Failure was defined as IOP > 21 mmHg or not reduced by 20% below baseline on two consecutive follow-up visits after 3 months, IOP ≤ 5 mmHg on two consecutive follow-up visits after 3 months, reoperation for glaucoma, or loss of light perception vision. Statistical methods consisted of Student's t-tests, chi-squared test, and Kaplan-Meier time to failure analysis. Results Fifty eyes (17 inferior, 33 superior) of 43 patients were enrolled. Mean postoperative follow-up in both groups were similar (mean 26.2 ± 15.2 for inferior and 23.9 ± 10.43 months for superior, p=0.54). Prior trabeculectomy had been performed in 8/17 (47%) and 11/33 (33%) eyes (p=0.34) with inferior and superior implants, respectively. Mean preoperative IOP (mmHg) in the superior group (26 ± 11) was significantly higher (p=0.02) than in the inferior group (21 ± 7). Success rates were similar (p>0.05) between the inferior and superior GDD groups during the study period, with 64.7% and 75.8% classified as successful at 1-year of follow-up and 43.1% and 65.7% at 2-years of follow-up, respectively. There was no difference in cumulative proportions of eyes failing between the groups (p=0.20, log-rank test). Mean postoperative IOP and number of anti

  15. Carbon phosphide monolayers with superior carrier mobility

    NASA Astrophysics Data System (ADS)

    Wang, Gaoxue; Pandey, Ravindra; Karna, Shashi P.

    2016-04-01

    Two dimensional (2D) materials with a finite band gap and high carrier mobility are sought after materials from both fundamental and technological perspectives. In this paper, we present the results based on the particle swarm optimization method and density functional theory which predict three geometrically different phases of the carbon phosphide (CP) monolayer consisting of sp2 hybridized C atoms and sp3 hybridized P atoms in hexagonal networks. Two of the phases, referred to as α-CP and β-CP with puckered or buckled surfaces are semiconducting with highly anisotropic electronic and mechanical properties. More remarkably, they have the lightest electrons and holes among the known 2D semiconductors, yielding superior carrier mobility. The γ-CP has a distorted hexagonal network and exhibits a semi-metallic behavior with Dirac cones. These theoretical findings suggest that the binary CP monolayer is a yet unexplored 2D material holding great promise for applications in high-performance electronics and optoelectronics.Two dimensional (2D) materials with a finite band gap and high carrier mobility are sought after materials from both fundamental and technological perspectives. In this paper, we present the results based on the particle swarm optimization method and density functional theory which predict three geometrically different phases of the carbon phosphide (CP) monolayer consisting of sp2 hybridized C atoms and sp3 hybridized P atoms in hexagonal networks. Two of the phases, referred to as α-CP and β-CP with puckered or buckled surfaces are semiconducting with highly anisotropic electronic and mechanical properties. More remarkably, they have the lightest electrons and holes among the known 2D semiconductors, yielding superior carrier mobility. The γ-CP has a distorted hexagonal network and exhibits a semi-metallic behavior with Dirac cones. These theoretical findings suggest that the binary CP monolayer is a yet unexplored 2D material holding great

  16. Information Superiority generated through proper application of Geoinformatics

    NASA Astrophysics Data System (ADS)

    Teichmann, F.

    2012-04-01

    , handle, distribute and store geodata will can reduce costs, strengthen the ties between service costumer and geodata provider and improve the contribution geoscience can make for achieving information superiority for decision makers.

  17. Chloride-selective electrodes based on "two-wall" aryl-extended calix[4]pyrroles: combining hydrogen bonds and anion-π interactions to achieve optimum performance.

    PubMed

    Sabek, Jad; Adriaenssens, Louis; Guinovart, Tomàs; Parra, Enrique J; Rius, F Xavier; Ballester, Pablo; Blondeau, Pascal

    2015-01-01

    The performance of chloride-selective electrodes based on "two-wall" aryl-extended calix[4]pyrroles and multiwall carbon nanotubes is presented. The calix[4]pyrrole receptors bear two phenyl groups at opposite meso-positions. When the meso-phenyl groups are decorated with strong electron-withdrawing substituents, attractive anion-π interactions may exist between the receptor's aromatic walls and the sandwiched anion. These anion-π interactions are shown to significantly affect the selectivity of the electrodes. Calix[4]pyrrole, bearing a p-nitro withdrawing group on each of the meso-phenyl rings, afforded sensors that display anti-Hofmeister behavior against the lipophilic salicylate and nitrate anions. Based on the experimental data, a series of principles that help in predicting the suitability of synthetic receptors for use as anion-specific ionophores is discussed. Finally, the sensors deliver excellent results in the direct detection of chloride in bodily fluids.

  18. A Causal-Comparative Study: Determining the Diffference in Principals' Beliefs Regarding Order of Change for Closing Achievement Gaps High-Performing Schools as Compared to Low-Performing Schools

    ERIC Educational Resources Information Center

    Colvin, Lisa J.

    2012-01-01

    Student achievement is inconsistent when comparing subgroups of students in public schools (Finn, 1999; Spellings, 2008; Teale, Paciga, & Hoffman, 2007). According to research, effective school principals believe that the problem is internal and subject to their control to effect change by addressing inequities. The changes required in closing…

  19. Learning from the best leads to superior performance.

    PubMed

    Camp, R C

    1992-01-01

    Xerox Corp., one of the earliest US proponents of benchmarking, has institutionalized the practice in its organization. This had lead to fundamental changes in how Xerox manages suppliers and develops products.

  20. Differentiation in Coregonus zenithicus in Lake Superior

    USGS Publications Warehouse

    Todd, Thomas N.; Smith, Gerald R.

    1980-01-01

    Morphological variation in Coregonus zenithicus has long plagued biologists working on Lake Superior ciscoes. Some of this variation is due to allometric growth; earlier workers incorrectly recognized large C. zenithicus as a distinct species, C. nigripinnis cyanopterus. Coregonus reighardi dymondi is a variant of C. zenithicus in northern bays of Lake Superior and Lake Nipigon. The morphological differences between members of spring and fall spawning populations of C. zenithicus in Lake Superior are no greater than those between geographically separate populations. We conclude that spawning time and geographic isolation act similarly in effecting differentiation of coregonine populations, and that populations with different spawning times do not necessarily represent different species.Key words: Coregonus zenithicus, cisco, Great Lakes, multivariate morphometrics, endangered species, taxonomy