WorldWideScience

Sample records for serialization performance enhancement

  1. How Do We Write about Performance in Serial Television?

    Directory of Open Access Journals (Sweden)

    Elliott Logan

    2015-05-01

    Full Text Available Television studies has produced few sustained analyses of performance in serial television. Yet film studies scholarship has shown how attending to the integration of performances with other aspects of film style is crucial to the interpretation and appreciation of expression and meaning in filmed narrative fictions. However, as a particle form of filmed serial narrative, series television raises a number of questions about performance that will not necessarily be satisfyingly addressed by the direct adoption and application of approaches to writing about performance that have been honed in regard to film. How, then, do we write about performance in television serials in ways that recognise and accommodate the form’s relationship to film, while at the same time appropriately acknowledging and responding to long-form television’s serial status? To examine the difficulties and opportunities of approaching performance in serial television this way, the article conducts close readings of various pieces of television studies writing on performance, by scholars such as Jason Mittell, Sue Turnbull, George Toles, and Steven Peacock. Their work brings into view film and television’s points of common relation, and the distinctive challenges, achievements, and rewards of appreciating the best television serials, and the performances in them.

  2. Hierarchical neural networks perform both serial and parallel processing.

    Science.gov (United States)

    Agliari, Elena; Barra, Adriano; Galluzzi, Andrea; Guerra, Francesco; Tantari, Daniele; Tavani, Flavia

    2015-06-01

    In this work we study a Hebbian neural network, where neurons are arranged according to a hierarchical architecture such that their couplings scale with their reciprocal distance. As a full statistical mechanics solution is not yet available, after a streamlined introduction to the state of the art via that route, the problem is consistently approached through signal-to-noise technique and extensive numerical simulations. Focusing on the low-storage regime, where the amount of stored patterns grows at most logarithmical with the system size, we prove that these non-mean-field Hopfield-like networks display a richer phase diagram than their classical counterparts. In particular, these networks are able to perform serial processing (i.e. retrieve one pattern at a time through a complete rearrangement of the whole ensemble of neurons) as well as parallel processing (i.e. retrieve several patterns simultaneously, delegating the management of different patterns to diverse communities that build network). The tune between the two regimes is given by the rate of the coupling decay and by the level of noise affecting the system. The price to pay for those remarkable capabilities lies in a network's capacity smaller than the mean field counterpart, thus yielding a new budget principle: the wider the multitasking capabilities, the lower the network load and vice versa. This may have important implications in our understanding of biological complexity. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. Serial Killing of Tumor Cells by Human Natural Killer Cells – Enhancement by Therapeutic Antibodies

    Science.gov (United States)

    Bhat, Rauf; Watzl, Carsten

    2007-01-01

    Background Natural killer cells are an important component of the innate immune system. Anti-cancer therapies utilizing monoclonal antibodies also rely on the cytotoxicity of NK cells for their effectiveness. Here, we study the dynamics of NK cell cytotoxicity. Methodology/Principal Findings We observe that IL-2 activated human NK cells can serially hit multiple targets. Using functional assays, we demonstrate that on an average, a single IL-2 activated NK cell can kill four target cells. Data using live video microscopy suggest that an individual NK cell can make serial contacts with multiple targets and majority of contacts lead to lysis of target cells. Serial killing is associated with a loss of Perforin and Granzyme B content. A large majority of NK cells survive serial killing, and IL-2 can replenish their granular stock and restore the diminished cytotoxicity of ‘exhausted’ NK cells. IL-2 and IL-15 are equally effective in enhancing the killing frequency of resting NK cells. Significantly, Rituximab, a therapeutic monoclonal antibody increases the killing frequency of both resting and IL-2 activated NK cells. Conclusion/Significance Our data suggest that NK cell-based therapies for overcoming tumors rely on their serial killing ability. Therefore, strategies augmenting the killing ability of NK cells can boost the immune system and enhance the effectiveness of monoclonal antibody-based therapies. PMID:17389917

  4. Serial killing of tumor cells by human natural killer cells--enhancement by therapeutic antibodies.

    Science.gov (United States)

    Bhat, Rauf; Watzl, Carsten

    2007-03-28

    Natural killer cells are an important component of the innate immune system. Anti-cancer therapies utilizing monoclonal antibodies also rely on the cytotoxicity of NK cells for their effectiveness. Here, we study the dynamics of NK cell cytotoxicity. We observe that IL-2 activated human NK cells can serially hit multiple targets. Using functional assays, we demonstrate that on an average, a single IL-2 activated NK cell can kill four target cells. Data using live video microscopy suggest that an individual NK cell can make serial contacts with multiple targets and majority of contacts lead to lysis of target cells. Serial killing is associated with a loss of Perforin and Granzyme B content. A large majority of NK cells survive serial killing, and IL-2 can replenish their granular stock and restore the diminished cytotoxicity of 'exhausted' NK cells. IL-2 and IL-15 are equally effective in enhancing the killing frequency of resting NK cells. Significantly, Rituximab, a therapeutic monoclonal antibody increases the killing frequency of both resting and IL-2 activated NK cells. Our data suggest that NK cell-based therapies for overcoming tumors rely on their serial killing ability. Therefore, strategies augmenting the killing ability of NK cells can boost the immune system and enhance the effectiveness of monoclonal antibody-based therapies.

  5. Serial killing of tumor cells by human natural killer cells--enhancement by therapeutic antibodies.

    Directory of Open Access Journals (Sweden)

    Rauf Bhat

    Full Text Available BACKGROUND: Natural killer cells are an important component of the innate immune system. Anti-cancer therapies utilizing monoclonal antibodies also rely on the cytotoxicity of NK cells for their effectiveness. Here, we study the dynamics of NK cell cytotoxicity. METHODOLOGY/PRINCIPAL FINDINGS: We observe that IL-2 activated human NK cells can serially hit multiple targets. Using functional assays, we demonstrate that on an average, a single IL-2 activated NK cell can kill four target cells. Data using live video microscopy suggest that an individual NK cell can make serial contacts with multiple targets and majority of contacts lead to lysis of target cells. Serial killing is associated with a loss of Perforin and Granzyme B content. A large majority of NK cells survive serial killing, and IL-2 can replenish their granular stock and restore the diminished cytotoxicity of 'exhausted' NK cells. IL-2 and IL-15 are equally effective in enhancing the killing frequency of resting NK cells. Significantly, Rituximab, a therapeutic monoclonal antibody increases the killing frequency of both resting and IL-2 activated NK cells. CONCLUSION/SIGNIFICANCE: Our data suggest that NK cell-based therapies for overcoming tumors rely on their serial killing ability. Therefore, strategies augmenting the killing ability of NK cells can boost the immune system and enhance the effectiveness of monoclonal antibody-based therapies.

  6. On the Performance of the Python Programming Language for Serial and Parallel Scientific Computations

    Directory of Open Access Journals (Sweden)

    Xing Cai

    2005-01-01

    Full Text Available This article addresses the performance of scientific applications that use the Python programming language. First, we investigate several techniques for improving the computational efficiency of serial Python codes. Then, we discuss the basic programming techniques in Python for parallelizing serial scientific applications. It is shown that an efficient implementation of the array-related operations is essential for achieving good parallel performance, as for the serial case. Once the array-related operations are efficiently implemented, probably using a mixed-language implementation, good serial and parallel performance become achievable. This is confirmed by a set of numerical experiments. Python is also shown to be well suited for writing high-level parallel programs.

  7. Effects of gender stereotypes on performance in mathematics: A serial multivariable mediation model

    National Research Council Canada - National Science Library

    Song, Jingjing; Zuo, Bin; Yan, Lei

    2016-01-01

    ... stereotypes about mathematics had a negative direct and indirect effect on Chinese female students' mathematics performance: the girls with a stronger gender stereotype were serially associated with less competence belief, lower performance-approach goals, and less effort, all of which, in turn, were associated with poorer performance in mathemat...

  8. Spatio-Temporal Serial Performance in Children and Adults

    Science.gov (United States)

    Foley, Wayne Edward; Lippman, Louis G.

    1970-01-01

    Neither adults' nor children's performances on a reconstruction task was affected by spatial variation, but children's performance was influenced by variation in the temporal sequence of stimulus presentation. This article is based upon an M.A. thesis by the first author under supervision of the second author. A version of this paper was presented…

  9. Serial Doppler echocardiographic assessment of left and right ventricular performance after a first myocardial infarction

    DEFF Research Database (Denmark)

    Møller, J E; Søndergaard, E; Poulsen, S H

    2001-01-01

    a first myocardial infarction (MI). To do so, serial Doppler echocardiography was performed in 77 consecutive patients with a first MI. Right ventricular MPI correlated significantly with LV MPI (r = 0.51, P signs of RV MI, the RV MPI was significantly higher (0...

  10. Examining the Relationship between Free Recall and Immediate Serial Recall: The Effect of Concurrent Task Performance

    Science.gov (United States)

    Bhatarah, Parveen; Ward, Geoff; Tan, Lydia

    2006-01-01

    In 3 experiments, participants saw lists of 16 words for free recall with or without a 6-digit immediate serial recall (ISR) task after each word. Free recall was performed under standard visual silent and spoken-aloud conditions (Experiment 1), overt rehearsal conditions (Experiment 2), and fixed rehearsal conditions (Experiment 3). The authors…

  11. Deployment and future prospects of high performance diagnostics featuring serial I/O (SIO) data acquisition (DAQ) at ASDEX Upgrade

    Energy Technology Data Exchange (ETDEWEB)

    Behler, K., E-mail: karl.behler@ipp.mpg.de [Max-Planck-Institut fuer Plasmaphysik, Boltzmannstr. 2, D-85748 Garching bei Muenchen (Germany); Blank, H.; Eixenberger, H. [Max-Planck-Institut fuer Plasmaphysik, Boltzmannstr. 2, D-85748 Garching bei Muenchen (Germany); Fitzek, M. [Unlimited Computer Systems GmbH, Seeshaupterstr. 15, D-82393 Iffeldorf (Germany); Lohs, A. [Max-Planck-Institut fuer Plasmaphysik, Boltzmannstr. 2, D-85748 Garching bei Muenchen (Germany); Lueddecke, K. [Unlimited Computer Systems GmbH, Seeshaupterstr. 15, D-82393 Iffeldorf (Germany); Merkel, R. [Max-Planck-Institut fuer Plasmaphysik, Boltzmannstr. 2, D-85748 Garching bei Muenchen (Germany)

    2012-12-15

    Highlights: Black-Right-Pointing-Pointer The high sustained data rates transferring measured data from periphery into memory of computers. Black-Right-Pointing-Pointer The achieved low latency in real-time interrupt handling under Solaris 10. Black-Right-Pointing-Pointer The new prototype of an even more powerful 2nd generation SIO II device. Black-Right-Pointing-Pointer The fusion of all blocks of board logic (serializer, FIFO, TDC, merge engine, PCIe controller) into one single FPGA simplifying the boards physical layout significantly. - Abstract: The SIO DAQ concept used at the ASDEX Upgrade fusion experiment features data acquisition from a modular front-end (a modular crate-and-interface-cards concept for analog and digital input and output) over standardized serial lines and via a serial input/output computer interface card (the SIO card) in real-time directly into the main memory of a host computer. Deployment of a series of diagnostics using SIO led to various solutions and configurations for the different requirements. Experience has been gained and lessons learned applying the SIO concept at its technical limits. Requirements for a further development of the SIO concept have been identified, and a performance improvement by a factor of 4-8 beyond its current limits seems achievable. An effort has been started to develop a SIO version 2 (SIO II) featuring upgraded serial links and a more powerful FPGA for merging and forwarding data streams to host computer memory. (Compatibility with the existing SIO (SIO I) front-end system has to be maintained.) This paper presents results achieved and experiences gained in the deployment of SIO I, the status of SIO II development (currently in the prototype phase), and projected enhancements and updates to existing implementations.

  12. The cortisol awakening response is associated with performance of a serial sequence reaction time task.

    Science.gov (United States)

    Hodyl, Nicolette A; Schneider, Luke; Vallence, Ann-Maree; Clow, Angela; Ridding, Michael C; Pitcher, Julia B

    2016-02-01

    There is emerging evidence of a relationship between the cortisol awakening response (CAR) and the neural mechanisms underlying learning and memory. The aim of this study was to determine whether the CAR is associated with acquisition, retention and overnight consolidation or improvement of a serial sequence reaction time task. Salivary samples were collected at 0, 15, 30 and 45 min after awakening in 39 healthy adults on 2 consecutive days. The serial sequence reaction time task was repeated each afternoon. Participants completed the perceived stress scale and provided salivary samples prior to testing for cortisol assessment. While the magnitude of the CAR (Z score) was not associated with either baseline performance or the timed improvement during task acquisition of the serial sequence task, a positive correlation was observed with reaction times during the stable performance phase on day 1 (r=0.373, p=0.019). Residuals derived from the relationship between baseline and stable phase reaction times on day 1 were used as a surrogate for the degree of learning: these residuals were also correlated with the CAR mean increase on day 1 (r=0.357, p=0.048). Task performance on day 2 was not associated with the CAR obtained on this same day. No association was observed between the perceived stress score, cortisol at testing or task performance. These data indicate that a smaller CAR in healthy adults is associated with a greater degree of learning and faster performance of a serial sequence reaction time task. These results support recognition of the CAR as an important factor contributing to cognitive performance throughout the day. Copyright © 2015 Elsevier B.V. All rights reserved.

  13. The relationship between end-state comfort effects and memory performance in serial and free recall.

    Science.gov (United States)

    Logan, S Wood; Fischman, Mark G

    2011-07-01

    In two experiments we examined the relationship between end-state comfort effects and memory performance in serial and free recall. In Experiment 1, 24 university students completed a bimanual end-state comfort task and a memory task. Participants viewed a series of 11 letters, then performed the bimanual overturned glass task in which they simultaneously moved two glasses from an upper shelf to a lower shelf, and then recalled the letters in either serial or free recall conditions. Memory recall was evaluated based on the presence or absence of primacy and recency effects. The end-state comfort effect was assessed by the percentage of initial hand positions that allowed the hands to end up in a comfortable thumbs-up posture. The end-state comfort effect was present in both memory conditions. The results revealed the disappearance of the recency effect in serial and free recall, although the effect was much stronger during serial recall. In Experiment 2, we asked whether simpler motor tasks might bring back the recency effect. Forty-eight participants completed either a bimanual or unimanual task that involved moving non-descript plastic cylinder(s) from an upper shelf to a lower shelf. An unexpected finding was that even after performance of the simpler motor tasks, the recency effect was still absent. The disappearance of the recency effect, regardless of the complexity of the motor task, suggests a reciprocal influence of physical action and cognitive processes, which we interpret as a basic concurrence cost. Copyright © 2011 Elsevier B.V. All rights reserved.

  14. Enhancing LAN performance

    CERN Document Server

    Held, Gilbert

    2004-01-01

    Enhancing LAN Performance, Fourth Edition explains how to connect geographically separated LANs with appropriate bandwidth, the issues to consider when weighing the use of multiport or dualport devices, how to estimate traffic for new networks, the effects of configuration changes on the performance of Ethernet and Token Ring networks, the design of switch-based networks that prevent traffic bottlenecks, and other critical topics. It provides the tools to address these issues in relation to specific network requirements. This volume develops mathematical models of various LAN performance issue

  15. Plant performance enhancement program

    Energy Technology Data Exchange (ETDEWEB)

    Munchausen, J.H. [EPRI Plant Support Engineering, Charlotte, NC (United States)

    1995-09-01

    The Plant Performance Enhancement Program (P{sup 2}EP), an initiative of the Electric Power Research Institute (EPRI), responds to strong industry incentives to improve nuclear plant thermal efficiency and electrical output. Launched by EPRI`s Nuclear Power Division, P{sup 2}EP operates within the purview of the Plant Support Engineering (PSE) Program, with day-to-day activities conducted out of the P{sup 2}EP office headquartered at EPRI`s facility in Charlotte, North Carolina. This alignment is consistent with EPFU`s strategic targets in support of industry goals, keeping P{sup 2}EP`s mission in clear focus: Helping utility thermal performance engineers improve the heat rate of nuclear power plants, thereby increasing unit average capacity and reducing plant operations and maintenance costs per kilowatt-hour.

  16. Neuronal correlates of serial position performance in amnestic mild cognitive impairment.

    Science.gov (United States)

    Kasper, Elisabeth; Brueggen, Katharina; Grothe, Michel J; Bruno, Davide; Pomara, Nunzio; Unterauer, Elisabeth; Duering, Marco; Ewers, Michael; Teipel, Stefan; Buerger, Katharina

    2016-11-01

    Delayed recall of the first words of a list-the primacy position-is thought to be particularly dependent on intact memory consolidation. Hippocampal volume has been suggested as the primary neuronal correlate of delayed primacy recall in cognitively normal elderly individuals. Here, we studied the association of hippocampal volume with primacy recall in individuals with amnestic mild cognitive impairment (aMCI). We investigated serial position performance in 88 subjects with aMCI using a 16-word list (the California Verbal Learning Test [CVLT]). Primacy and recency performance were measured during learning and delayed recall. Hippocampal volumes were automatically determined from structural MRI scans. We conducted regression analyses with bilateral hippocampal volumes as predictors and serial position indices as outcomes. After controlling for age, gender, and total intracranial volume, bilateral hippocampal volume was not associated with primacy recall either during learning or delayed recall. Primacy performance during learning was associated with the right inferior and middle temporal gyrus as well as the right inferior parietal cortex and supramerginal gyrus. During delayed recall, primacy performance was related to the bilateral supramarginal gyri. Our findings suggest a reduced primacy effect in aMCI already during learning, contrasting previous findings in normal cognitive aging. This might indicate impaired encoding and consolidation processes at an early stage of episodic memory acquisition. Furthermore, our data indicate that hippocampal volume may not be a relevant determinant of residual primacy performance in the stage of aMCI, which may rather depend on temporal and parietal neocortical networks. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  17. Design and Performance of a PCI Interface with four 2 Gbit/s Serial Optical Links

    CERN Document Server

    Haas, S; Iwanski, W; 10th Workshop on Electronics for LHC and Future Experiments

    2004-01-01

    A reconfigurable PCI interface card (FILAR) with four on-board high-speed serial optical links has been developed for application in DAQ and test systems. FILAR cards, installed in low cost PCs, are currently being used in the combined test-beam of the ATLAS experiment at CERN as well as in several laboratory set-ups. The hardware and firmware design of the module and results from performance measurements are presented. The four on-board 2 Gbit/s serial optical links conform to the S-LINK specification and are compatible with the Readout Link (ROL) implementation for the ATLAS experiment. The board design is largely based on FPGAs and the firmware uses a commercial 64-bit/66 MHz PCI IP core for the bus interface. Different firmware versions were developed which can be used to configure the hardware as either a data source or a destination card. Design optimizations have been made during the development cycle of the firmware to maximize the data throughput and reduce the PCI bus overhead as well as the CPU loa...

  18. Serial tempering without exchange.

    Science.gov (United States)

    Nymeyer, Hugh

    2010-09-21

    Serial tempering is a computational method that turns the temperature T (or more generally any independent λ parameter) into a dynamical variable. It is shown that, under conditions for which this variable is fast, serial tempering is equivalent to the umbrella sampling method with a single effective potential. This equivalence is demonstrated using both a small one-dimensional system and a small solvated peptide. The suggestion is then made to replace the serial tempering protocol with the equivalent umbrella sampling calculation. This approach, serial tempering without exchange (STeWiE), has the same performance as serial tempering in the limit that exchanges are frequent, is simpler to implement, and has fewer adjustable parameters than conventional serial tempering. The equivalence of serial tempering and STeWiE also provides a convenient route for estimating and optimizing the performance of serial tempering simulations and other generalized-ensemble methods.

  19. Effect of post-digestion temperature on serial CSTR biogas reactor performance

    DEFF Research Database (Denmark)

    Boe, Kanokwan; Karakashev, Dimitar Borisov; Trably, Eric

    2009-01-01

    of 5.3 days. Three post-digestion temperatures (55 degrees C, 37 degrees C and 15 degrees C) were compared in terms of biogas production, process stability, microbial community and methanogenic activity, The results showed that the post-digesters operated at 55 degrees C, 37 degrees C and 15 degrees C...... gave extra biogas production of 11.7%, 8.4% and 1.2%, respectively. The post-digester operated at 55 degrees C had the highest biogas production and was the most stable in terms of low VFA concentrations. The specific methanogenic activity tests revealed that the main reactor and the post-digester......The effect of post-digestion temperature on a lab-scale serial continuous-flow stirred tank reactor (CSTR) system performance was investigated. The system consisted of a main reactor operated at 55 degrees C with hydraulic retention time (HRT) of 15 days followed by post-digestion reactors with HRT...

  20. Redundant sensory information does not enhance sequence learning in the serial task

    NARCIS (Netherlands)

    Abrahamse, E.L.; van der Lubbe, Robert Henricus Johannes; Verwey, Willem B.; Szumska, I.; Jaskowski, P.

    2012-01-01

    In daily life we encounter multiple sources of sensory information at any given moment. Unknown is whether such sensory redundancy in some way affects implicit learning of a sequence of events. In the current paper we explored this issue in a serial reaction time task. Our results indicate that

  1. Nicotine-induced enhancement of attention in the five-choice serial reaction time task: the influence of task demands.

    Science.gov (United States)

    Hahn, B; Shoaib, M; Stolerman, I P

    2002-07-01

    Beneficial effects of nicotine on cognitive processes including attention have potential therapeutic uses and have been proposed as incentives for tobacco smoking. To establish task conditions under which the effects of nicotine on attention are obtained reliably and to characterise such effects further. Rats were trained in a modified version of the five-choice serial reaction time task (5-CSRTT) to detect 1-s light stimuli with greater than 70% accuracy and fewer than 20% omission errors. Nicotine was tested under different task requirements by varying signal event rate, stimulus duration and stimulus predictability, and by introducing white-noise distractors. Nicotine (0.05-0.2 mg/kg, s.c.) repeatedly improved accuracy and reduced omission errors and reaction times, leading to increases in numbers of reinforcers earned. Anticipatory responding was increased. Parametric modifications intended to increase demands on sustained attention did not affect performance in a manner suggesting that this subtype of attention was being taxed, and the effects of nicotine were not more marked under such conditions. Shorter stimulus durations impaired performance, but this manipulation weakened the effect of nicotine on accuracy. In contrast, the presence of noise distractors facilitated the effects of nicotine to the extent that distractor-induced impairments were abolished by the drug. The 5-CSRTT can provide a sensitive rodent model for the attention-enhancing effects of nicotine. Changes made to the procedure may have increased its sensitivity to nicotine, particularly with respect to accuracy. There were indications that the effects of nicotine were largest on processes of selective attention or on disengaging attention from irrelevant events and shifting it to behaviourally significant stimuli.

  2. Beneficial effects of serial contractions on muscle performance after a brief period of rest.

    Science.gov (United States)

    Green, Lara A; Parro, Justin J; Gabriel, David A

    2014-08-01

    The study investigated potential mechanisms underlying the beneficial effects of performing serial contractions for increasing muscle performance. Thirteen men performed maximal isometric dorsiflexion contractions to a limited amount of fatigue. The recovery pattern was monitored over 15 min. Force, surface electromyography (sEMG) of the agonist and antagonist, and skin temperature were observed. Evoked potentials were elicited. Force decreased to 206 ± 40 N and recovered to 243 ± 55 N (102 % of initial value). While full recovery is noteworthy, it was not significant (p = 0.24). Surface EMG root-mean-square (RMS) amplitude did not fully recover: tibialis anterior (219 ± 46 versus 242 ± 63 μV, 91 %) and soleus (13 ± 5 versus 16 ± 6 μV, 82 %). The result was an 11 % decrease in the co-activation ratio during recovery. Tibialis anterior and soleus mean power frequency (MPF) "over-recovered" to 117 % (144 ± 25 versus 124 ± 27 Hz) and 118 % (80 ± 14 versus 68 ± 11 Hz) of initial value, respectively. Peak rate of force development (RFD) during recovery was 146 % of initial (743 ± 246 versus 509 ± 271 N). Skin temperature increased 0.6 °C over the test session. Potentiation was not present during recovery, as assessed by twitch force. The return of force to initial values, rather than a persistent decrement was a result of several mechanisms operating simultaneously. The sEMG data indicate an increase in conduction velocity, while an increase in peak RFD suggests contraction-induced facilitation of ATPase pump activity. However, alterations in muscle coordination were observed as a reduction in antagonist co-activity.

  3. Bone marrow stromal cell transplantation enhances recovery of local glucose metabolism after cerebral infarction in rats: a serial 18F-FDG PET study.

    Science.gov (United States)

    Miyamoto, Michiyuki; Kuroda, Satoshi; Zhao, Songji; Magota, Keiichi; Shichinohe, Hideo; Houkin, Kiyohiro; Kuge, Yuji; Tamaki, Nagara

    2013-01-01

    This study aimed to assess whether (18)F-FDG PET could serially monitor the beneficial effects of bone marrow stromal cells (BMSC) on cerebral glucose metabolism when transplanted into the infarct brain of rats. The BMSC from green fluorescent protein transgenic rats or vehicle was stereotactically transplanted into the ipsilateral striatum at 7 d after permanent middle cerebral artery occlusion of rats. Local glucose metabolism was semiquantitatively measured at 6 and 35 d after ischemia using (18)F-FDG PET. Motor function was serially evaluated throughout the experiments. At 35 d after ischemia, immunohistochemistry was performed to evaluate the phenotype of BMSC and their effects on the expression of brain-type glucose transporters. BMSC transplantation not only enhanced functional recovery but also promoted the recovery of glucose utilization in the periinfarct area when stereotactically transplanted at 1 wk after ischemia. The engrafted cells were widely distributed, and most expressed a neuron-specific protein, NeuN. BMSC transplantation also prevented the pathologic upregulation of glucose transporters in the periinfarct neocortex. The present findings strongly suggest that the BMSC may enhance functional recovery by promoting the recovery of local glucose metabolism in the periinfarct area when directly transplanted into the infarct brain at clinically relevant timing. The BMSC also inhibit the pathologic upregulation of brain-isoform glucose transporters type 1 and 3. (18)F-FDG PET may be a valuable modality to scientifically prove the beneficial effects of BMSC transplantation on the host brain in clinical situations.

  4. Male bumblebees, Bombus terrestris, perform equally well as workers in a serial colour-learning task.

    Science.gov (United States)

    Wolf, Stephan; Chittka, Lars

    2016-01-01

    The learning capacities of males and females may differ with sex-specific behavioural requirements. Bumblebees provide a useful model system to explore how different lifestyles are reflected in learning abilities, because their (female but sterile) workers and males engage in fundamentally different behaviour routines. Bumblebee males, like workers, embark on active flower foraging but in contrast to workers they have to trade off their feeding with mate search, potentially affecting their abilities to learn and utilize floral cues efficiently during foraging. We used a serial colour-learning task with freely flying males and workers to compare their ability to flexibly learn visual floral cues with reward in a foraging scenario that changed over time. Male bumblebees did not differ from workers in both their learning speed and their ability to overcome previously acquired associations, when these ceased to predict reward. In all foraging tasks we found a significant improvement in choice accuracy in both sexes over the course of the training. In both sexes, the characteristics of the foraging performance depended largely on the colour difference of the two presented feeder types. Large colour distances entailed fast and reliable learning of the rewarding feeders whereas choice accuracy on highly similar colours improved significantly more slowly. Conversely, switching from a learned feeder type to a novel one was fastest for similar feeder colours and slow for highly different ones. Overall, we show that behavioural sex dimorphism in bumblebees did not affect their learning abilities beyond the mating context. We discuss the possible drivers and limitations shaping the foraging abilities of males and workers and implications for pollination ecology. We also suggest stingless male bumblebees as an advantageous alternative model system for the study of pollinator cognition.

  5. Is performance on probed serial recall tasks in schizophrenia related to duration of Attentional Blink?

    Directory of Open Access Journals (Sweden)

    David P. McAllindon

    2017-03-01

    Full Text Available Schizophrenia is associated with a deficit in working memory, with the degree of working memory impairment related to the level of social and occupational functioning. This study tests the hypothesis that the working memory deficits in individuals with schizophrenia can be explained by slow processing of visual stimuli, as measured by the attentional blink (AB task. Individuals with schizophrenia (SC and controls (HC were recruited from an early intervention service for psychosis and the local community. Data from 16 SC (11M/5F, mean = 26.4 yo and 20 age-matched HC (11M/9F, mean = 25.8 yo were analyzed. Each subject performed an AB task to determine their AB duration, defined as the lag to reach their plateau performance (ltpp. As expected, mean AB duration in the SC group (575 ms was significantly slower than HC (460 ms; p = 0.007. Recall accuracy of the SC group on a working memory task, a 6-item probed serial recall task (PSR, was reduced compared to the HC group at a standard interstimulus interval (ISI (p = 0.002. When the individual's AB duration was then used to adjust the ISI on the PSR task to three relative ISI rates (Slow (2 × ltpp, Medium (ltpp and Fast (1/2 × ltpp, performance on the PSR task was affected by group, position and ISI and qualified by an ISI ∗ position (p = 0.001 and a trend to a triple interaction (p = 0.054. There was main effect of group at all ISIs, but group ∗ position interaction only at Slow ISI (p = 0.01. Our interpretation of the results is that absolute ISI, rather than ISI relative to AB duration, affected performance.

  6. Transitional Information in Spatial Serial Memory: Path Characteristics Affect Recall Performance

    Science.gov (United States)

    Parmentier, Fabrice B. R.; Elford, Greg; Mayberry, Murray

    2005-01-01

    This study examined the role of stimulus characteristics in a visuospatial order reconstruction task in which participants were required to recall the order of sequences of spatial locations. The complexity of the to-be-remembered sequences, as measured by path crossing, path length, and angles, was found to affect serial memory, in terms of both…

  7. Fine motor movements while drawing during the encoding phase of a serial verbal recall task reduce working memory performance.

    Science.gov (United States)

    Tindle, Richard; Longstaff, Mitchell G

    2016-02-01

    The time-based resource-sharing (TBRS) model of working memory indicates that secondary tasks that capture attention for relatively long periods can result in the interference of working memory processing and maintenance. The current study investigates if discrete and continuous movements have differing effects on a concurrent, verbal serial recall task. In the listening condition, participants were asked to recall spoken words presented in lists of six. In the drawing conditions, participants performed the same task while producing discrete (star) or continuous (circle) movements. As hypothesised, participants recalled more words overall in the listening condition compared to the combined drawing conditions. The prediction that the continuous movement condition would reduce recall compared to listening was also supported. Fine-grained analysis at each serial position revealed significantly more words were recalled at mid serial positions in the listening condition, with worst recall for the continuous condition at position 5 compared to the listening and discrete conditions. Kinematic analysis showed that participants increased the size and speed of the continuous movements resulting in a similar duration and number of strokes for each condition. The duration of brief pauses in the discrete condition was associated with the number of words recalled. The results indicate that fine motor movements reduced working memory performance; however, it was not merely performing a movement but the type of the movement that determined how resources were diverted. In the context of the TBRS, continuous movements could be capturing attention for longer periods relative to discrete movements, reducing verbal serial recall. Copyright © 2016 Elsevier B.V. All rights reserved.

  8. Nomarski serial time-encoded amplified microscopy for high-speed contrast-enhanced imaging of transparent media.

    Science.gov (United States)

    Fard, Ali M; Mahjoubfar, Ata; Goda, Keisuke; Gossett, Daniel R; Di Carlo, Dino; Jalali, Bahram

    2011-12-01

    High-speed high-contrast imaging modalities that enable image acquisition of transparent media without the need for chemical staining are essential tools for a broad range of applications; from semiconductor process monitoring to blood screening. Here we introduce a method for contrast-enhanced imaging of unstained transparent objects that is capable of high-throughput imaging. This method combines the Nomarski phase contrast capability with the ultrahigh frame rate and shutter speed of serial time-encoded amplified microscopy. As a proof of concept, we show imaging of a transparent test structure and white blood cells in flow at a shutter speed of 33 ps and a frame rate of 36.1 MHz using a single-pixel photo-detector. This method is expected to be a valuable tool for high-throughput screening of unstained cells.

  9. Business ownership experience, entrepreneurial behaviour and performance: novice, habitual, serial and portfolio entrepreneurs

    OpenAIRE

    Ucbasaran, Ayse Deniz

    2004-01-01

    Recent media reports have drawn attention to entrepreneurs who have successfully owned several businesses. Entrepreneurs who have owned at least two businesses are known as 'habitual entrepreneurs'. However, not all habitual entrepreneurs are consistently successful. Further, studies show that habitual entrepreneurs are heterogeneous. A distinction has been made between portfolio entrepreneurs (i.e., those who own multiple businesses simultaneously) and serial entrepreneurs (i.e., those who h...

  10. Combined dynamic contrast-enhancement and serial 3D-subtraction analysis in magnetic resonance imaging of osteoid osteomas

    Energy Technology Data Exchange (ETDEWEB)

    Kalle, T. von; Winkler, P. [Klinikum Stuttgart Olgahospital, Department of Paediatric Radiology, Stuttgart (Germany); Langendoerfer, M.; Fernandez, F.F. [Klinikum Stuttgart Olgahospital, Department of Paediatric Orthopaedics, Stuttgart (Germany)

    2009-10-15

    The purpose of this study was to retrospectively correlate the results of dynamic contrast-enhanced magnetic resonance imaging (MRI) with histological and clinical diagnoses in patients with osteoid osteomas. Fifty-four patients with the MR diagnosis of osteoid osteoma were studied. MRI (1.5 Tesla) consisted of thin-section STIR sequences, dynamic 3D T1 gradient echo sequences during application of contrast material, and high-resolution postcontrast T1 spin echo sequences with fat saturation (maximum voxel size 0.6 x 0.6 x 3.0 mm). Evaluation was focused on serial image subtraction during the early phase after contrast injection and on time-intensity curves. The surrounding edema was helpful in finding the nidus in each lesion. In 49 of 54 patients (90.7%), the diagnosis of osteoid osteoma was certain or highly probable (sensitivity 1.0, positive predictive value 0.91). A total of 38 of 54 osteoid osteomas were histologically proven. Five MRI diagnoses were regarded as false positives. A similar proportion has been reported for computed tomography. Tailored high-resolution MR examinations with dynamic contrast enhancement can reliably diagnose osteoid osteomas and exactly localize the nidus without radiation exposure. We propose a stepwise approach with STIR sequences, dynamic contrast-enhanced scanning, and high-resolution postcontrast T1 spin echo sequences with fat saturation. (orig.)

  11. Superparamagnetic enhancement of thermoelectric performance

    Science.gov (United States)

    Zhao, Wenyu; Liu, Zhiyuan; Sun, Zhigang; Zhang, Qingjie; Wei, Ping; Mu, Xin; Zhou, Hongyu; Li, Cuncheng; Ma, Shifang; He, Danqi; Ji, Pengxia; Zhu, Wanting; Nie, Xiaolei; Su, Xianli; Tang, Xinfeng; Shen, Baogen; Dong, Xiaoli; Yang, Jihui; Liu, Yong; Shi, Jing

    2017-09-01

    The ability to control chemical and physical structuring at the nanometre scale is important for developing high-performance thermoelectric materials. Progress in this area has been achieved mainly by enhancing phonon scattering and consequently decreasing the thermal conductivity of the lattice through the design of either interface structures at nanometre or mesoscopic length scales or multiscale hierarchical architectures. A nanostructuring approach that enables electron transport as well as phonon transport to be manipulated could potentially lead to further enhancements in thermoelectric performance. Here we show that by embedding nanoparticles of a soft magnetic material in a thermoelectric matrix we achieve dual control of phonon- and electron-transport properties. The properties of the nanoparticles—in particular, their superparamagnetic behaviour (in which the nanoparticles can be magnetized similarly to a paramagnet under an external magnetic field)—lead to three kinds of thermoelectromagnetic effect: charge transfer from the magnetic inclusions to the matrix; multiple scattering of electrons by superparamagnetic fluctuations; and enhanced phonon scattering as a result of both the magnetic fluctuations and the nanostructures themselves. We show that together these effects can effectively manipulate electron and phonon transport at nanometre and mesoscopic length scales and thereby improve the thermoelectric performance of the resulting nanocomposites.

  12. Performance Enhancement by Brain Stimulation

    Directory of Open Access Journals (Sweden)

    Parisa Gazerani

    2017-09-01

    Full Text Available Number of substances and strategies are available to increase performance in sport (Catlin and Murray, 1996. Since 2004, the World Anti-Doping Agency (WADA posts an updated list of substances and methods prohibited to athletes. Drugs (e.g., steroids, stimulants are a major part of this list; however, technologies and methods (e.g., gene doping are increasingly being identified and added (WADA, 2017. Among technologies and methods that might exert a potential effect on athletic performance, brain stimulation has recently been subjected to extensive discussion. Neuro-enhancement for doping purposes has been termed “neurodoping” in the literature (Davis, 2013; however, this concept needs further documentation before the term “neurodoping” can be used properly. Two major non-invasive techniques of brain stimulations are transcranial magnetic stimulation (TMS (Hallett, 2007; Rossi et al., 2009, and transcranial direct current stimulation (tDCS (Stagg and Nitsche, 2011. In TMS, an electric coil held over the head applies magnetic pulses to create currents in the brain. In tDCS, a low, continuous electrical current is delivered to the brain by using surface electrodes attached on the scalp. TMS and tDCS have been used in both research and clinic (Shin and Pelled, 2017 for example to examine alterations in cognitive function or motor skills or to assist in recovering motor function after a stroke (Gomez Palacio Schjetnan et al., 2013 or reducing fatigue in patients with multiple sclerosis (Saiote et al., 2014. In an opinion paper, it was proposed that use of emerging brain stimulation techniques might also enhance physical and mental performance in sports (Davis, 2013. The assumption was based on several reports. For example some studies have shown that TMS could shorten reaction times to visual, auditory and touch stimuli, reduce tremor, and enhance the acquisition of complex motor skills. Based on the current evidence, a recent review (Colzato

  13. Performance Pressure Enhances Speech Learning

    Science.gov (United States)

    Maddox, W. Todd; Koslov, Seth; Yi, Han-Gyol; Chandrasekaran, Bharath

    2015-01-01

    Real-world speech learning often occurs in high pressure situations such as trying to communicate in a foreign country. However, the impact of pressure on speech learning success is largely unexplored. In this study, adult, native speakers of English learned non-native speech categories under pressure or no-pressure conditions. In the pressure conditions, participants were informed that they were paired with a (fictitious) partner, and that each had to independently exceed a performance criterion for both to receive a monetary bonus. They were then informed that their partner had exceeded the bonus and the fate of both bonuses depended upon the participant’s performance. Our results demonstrate that pressure significantly enhanced speech learning success. In addition, neurobiologically-inspired computational modeling revealed that the performance advantage was due to faster and more frequent use of procedural learning strategies. These results integrate two well-studied research domains and suggest a facilitatory role of motivational factors in speech learning performance that may not be captured in traditional training paradigms. PMID:28077883

  14. Enhanced performance hybrid-arq

    KAUST Repository

    Fareed, Muhammad Mehboob

    2016-06-16

    Apparatuses, computer readable media, and methods are provided for enhancing hybrid automatic repeat request (ARQ) performance. In an example method, a communication device transmits a first element of a vector, where the vector is selected using the information bits to be transmitted as an index in a code book. In some embodiments, this code book is constructed using Linear Constellation Precoding (LCP). If a NACK is received, the communication device transmits a second element of the vector. The process of transmitting elements of the vector continues until an ACK is received or the maximum number of transmission attempts is reached. If an ACK is received, the communication device transmits a first element of another vector of the code book that encodes a second set of information bits. This procedure may continue until all information bits have been transmitted successfully.

  15. Poor Performance on Serial Visual Tasks in Persons with Reading Disabilities: Impaired Working Memory?

    Science.gov (United States)

    Ram-Tsur, Ronit; Faust, Miriam; Zivotofsky, Ari Z.

    2008-01-01

    The present study investigates the performance of persons with reading disabilities (PRD) on a variety of sequential visual-comparison tasks that have different working-memory requirements. In addition, mediating relationships between the sequential comparison process and attention and memory skills were looked for. Our findings suggest that PRD…

  16. Energy Savings Opportunities and Energy Efficiency Performance Indicators for a Serial Production Line

    OpenAIRE

    Brundage, Michael; Chang, Qing; Wang, Shiyao; Feng, Shaw; Xiao, Guoxian; Arinez, Jorge

    2013-01-01

    Part 2: Sustainable Supply Chains; International audience; Modern manufacturing facilities waste various energy savings opportunities (ESO) and lack proper performance indicators to measure energy efficiency on the production line. The ESO is an opportunity window calculated from on-line production data, such as production count, machine downtime records, buffer levels, and machine idle status, allowing certain machines to be turned off for energy savings without negatively affecting throughp...

  17. ATAMM enhancement and multiprocessor performance evaluation

    Science.gov (United States)

    Stoughton, John W.; Mielke, Roland R.; Som, Sukhamoy; Obando, Rodrigo; Malekpour, Mahyar R.; Jones, Robert L., III; Mandala, Brij Mohan V.

    1991-01-01

    ATAMM (Algorithm To Architecture Mapping Model) enhancement and multiprocessor performance evaluation is discussed. The following topics are included: the ATAMM model; ATAMM enhancement; ADM (Advanced Development Model) implementation of ATAMM; and ATAMM support tools.

  18. Selection and Serial Entrepreneurs

    DEFF Research Database (Denmark)

    Chen, Jing

    2013-01-01

    There is substantial evidence that serial entrepreneurs outperform de novo entrepreneurs. But is this positive association between prior experience and performance the result of learning by doing or of selection on ability? This paper proposes a strategy that combines the fixed-effects model and IV...... when the analysis focuses on founding new startups in sectors closely related to entrepreneurs' previous ventures....

  19. Longitudinal analyses of operant performance on the serial implicit learning task (SILT) in the YAC128 Huntington's disease mouse line.

    Science.gov (United States)

    Brooks, Simon P; Jones, Lesley; Dunnett, Stephen B

    2012-06-01

    Huntington's disease is a genetic disorder characterised by progressive striatal and cortical neurodegeneration, resulting in a broad range of motor, cognitive and behavioural abnormalities. The disease is caused by a single mutation in the gene responsible for the protein huntingtin, increasing the number of polyQ repeats and conferring a toxic gain of function to the mutant protein, which ultimately induces cell death. Several mouse models of HD are available. The YAC128 mouse model carries 128 CAG repeats and is known to develop several HD-like symptoms. This model has been well characterised on the FVB/N background strain, a strain that develops severe retinal degeneration. We have therefore sought to characterise YAC128 deficit in mice backcrossed onto the C57BL/6j background strain which is free of visual deficits and therefore more amenable to behavioural testing. In a parallel study (this special issue) we have provided a longitudinal characterisation of the emergence of a motor phenotype in the YAC128/C57BL mice. In the present paper, we have undertaken a more detailed characterisation of cognitive impairment in this mouse line at 6, 12, and 18 months of age using the operant serial implicit learning task (SILT), a task that was first designed to assess impairments in mice similar to the implicit serial learning impairments in HD patients task, and which has subsequently been shown to be highly sensitive to cortico-striatal disruption in mice. On the SILT task, the mouse must attain rewards by correctly nose-poking to 2 stimulus lights (S1 and S2) presented randomly and sequentially in 5 holes (deemed A-E) on a light array. Performance is measured by accuracy and speed of response to the S1 and S2 stimuli. Embedded within the random sequences, was a predictable sequence whereby an S1 in hole B is always followed by the S2 in hole D, which constitutes an implicit learning probe. The YAC128 carriers were less accurate in their responses to both S1 and S2

  20. Enhancing importance-performance analysis

    DEFF Research Database (Denmark)

    Eskildsen, Jacob Kjær; Kristensen, Kai

    2006-01-01

    Purpose: The interpretation of the importance/performance map is based on an assumption of independence between importance and performance but many studies question the validity of this assumption. The aim of this research is to develop a new typology for job satisfaction attributes as well...... in more than one subset. This is a problem with the data generating process that to some extent might influence the analysis. Practical implications: Profound impact on the way that the importance/performance map should be interpreted since non-proportional attributes will move both vertically as well...... as horizontally in the traditional importance/performance map as performance changes. Originality/value: This paper gives a theoretical explanation for the presence of non-proportional satisfiers and develops a new importance/performance map that takes the presence of non-proportional satisfiers into account....

  1. TCP Performance Enhancement Over Iridium

    Science.gov (United States)

    Torgerson, Leigh; Hutcherson, Joseph; McKelvey, James

    2007-01-01

    In support of iNET maturation, NASA-JPL has collaborated with NASA-Dryden to develop, test and demonstrate an over-the-horizon vehicle-to-ground networking capability, using Iridium as the vehicle-to-ground communications link for relaying critical vehicle telemetry. To ensure reliability concerns are met, the Space Communications Protocol Standards (SCPS) transport protocol was investigated for its performance characteristics in this environment. In particular, the SCPS-TP software performance was compared to that of the standard Transmission Control Protocol (TCP) over the Internet Protocol (IP). This paper will report on the results of this work.

  2. Perform or Else: The Performative Enhancement of Teacher Professionalism

    Science.gov (United States)

    Liew, Warren Mark

    2012-01-01

    The Singapore Ministry of Education's Enhanced Performance Management System (EPMS) was instituted in 2005 as a system of professional accountability to enhance the standards and stakes of teacher professionalism in schools. This essay explores how the EPMS, with its underlying paradigm of performance management, functions as a "technology of…

  3. Effects of amphetamine and methylphenidate on attentional performance and impulsivity in the mouse 5-Choice Serial Reaction Time Task

    DEFF Research Database (Denmark)

    Caballero Puntiverio, Maitane; Fitzpatrick, Ciarán Martin; Woldbye, David Paul Drucker

    2017-01-01

    Background: Few studies have investigated the effects of conventional attention deficit-hyperactivity disorder (ADHD) medication in the mouse 5-choice serial reaction time task (5-CSRTT), and rat studies have yielded inconsistent results. Objective: We aimed to examine the effects of acute...

  4. Enclosure enhancement of flight performance

    KAUST Repository

    Ghommem, Mehdi

    2014-08-19

    We use a potential flow solver to investigate the aerodynamic aspects of flapping flights in enclosed spaces. The enclosure effects are simulated by the method of images. Our study complements previous aerodynamic analyses which considered only the near-ground flight. The present results show that flying in the proximity of an enclosure affects the aerodynamic performance of flapping wings in terms of lift and thrust generation and power consumption. It leads to higher flight efficiency and more than 5% increase of the generation of lift and thrust.

  5. Enclosure enhancement of flight performance

    Directory of Open Access Journals (Sweden)

    Mehdi Ghommem

    2014-01-01

    Full Text Available We use a potential flow solver to investigate the aerodynamic aspects of flapping flights in enclosed spaces. The enclosure effects are simulated by the method of images. Our study complements previous aerodynamic analyses which considered only the near-ground flight. The present results show that flying in the proximity of an enclosure affects the aerodynamic performance of flapping wings in terms of lift and thrust generation and power consumption. It leads to higher flight efficiency and more than 5% increase of the generation of lift and thrust.

  6. Environmental Burkholderia cenocepacia Strain Enhances Fitness by Serial Passages during Long-Term Chronic Airways Infection in Mice

    Directory of Open Access Journals (Sweden)

    Alessandra Bragonzi

    2017-11-01

    Full Text Available Burkholderia cenocepacia is an important opportunistic pathogen in cystic fibrosis (CF patients, and has also been isolated from natural environments. In previous work, we explored the virulence and pathogenic potential of environmental B. cenocepacia strains and demonstrated that they do not differ from clinical strains in some pathogenic traits. Here, we investigated the ability of the environmental B. cenocepacia Mex1 strain, isolated from the maize rhizosphere, to persist and increase its virulence after serial passages in a mouse model of chronic infection. B. cenocepacia Mex1 strain, belonging to the recA lineage IIIA, was embedded in agar beads and challenged into the lung of C57Bl/6 mice. The mice were sacrificed after 28 days from infection and their lungs were tested for bacterial loads. Agar beads containing the pool of B. cenocepacia colonies from the four sequential passages were used to infect the mice. The environmental B. cenocepacia strain showed a low incidence of chronic infection after the first passage; after the second, third and fourth passages in mice, its ability to establish chronic infection increased significantly and progressively up to 100%. Colonial morphology analysis and genetic profiling of the Mex1-derived clones recovered after the fourth passage from infected mice revealed that they were indistinguishable from the challenged strain both at phenotypic and genetic level. By testing the virulence of single clones in the Galleria mellonella infection model, we found that two Mex1-derived clones significantly increased their pathogenicity compared to the parental Mex1 strain and behaved similarly to the clinical and epidemic B. cenocepacia LMG16656T. Our findings suggest that serial passages of the environmental B. cenocepacia Mex1 strain in mice resulted in an increased ability to determine chronic lung infection and the appearance of clonal variants with increased virulence in non-vertebrate hosts.

  7. Blended learning approaches enhance student academic performance

    OpenAIRE

    Morris, NP

    2010-01-01

    Blended learning, or technology enhanced learning, is increasingly becoming an expectation for higher education students. Blended learning allows for the enhancement of face-to-face interaction between tutors and students, using internet or computer based tools. In this paper, a range of case studies are described which illustrate methods to engage students with technology enhanced learning and improve academic performance and student satisfaction. In the first case study, first year undergra...

  8. Synthetic Jet Actuator Performance Enhancement

    Science.gov (United States)

    Pikcilingis, Lucia; Housley, Kevin; Whalen, Ed; Amitay, Michael; Rensselaer Polytechnic Institute Collaboration; Boeing Company Collaboration

    2014-11-01

    Over the last 20 years synthetic jets have been studied as a means for aerodynamic flow control. Specifically, synthetic jets provide momentum transfer with zero-net mass flux, which has been proven to be effective for controlling flow fields. A synthetic jet is created by the periodic formation of vortex rings at its orifice due to the periodic motion of a piezoelectric disk(s). The present study seeks to optimize the performance of a synthetic jet actuator by utilizing different geometrical parameters such as disk thickness, orifice width and length, cavity height and cavity diameter, and different input parameters such as voltage and frequency. Experiments were conducted using a synthetic jet apparatus designed for various geometrical parameters utilizing a dual disk configuration. Velocity and temperature measurements were acquired at the center of the synthetic jet orifice using a temperature compensated hotwire and thermocouple probe. The disk displacement was measured at the center of the disk with a laser displacement sensor. It was shown that the synthetic jet actuators are capable of exceeding peak velocities of 200 m/s with a relatively large orifice. Data suggests that jet velocities greater than 200 m/s are attainable.

  9. Performance-Enhancing Drugs: Know the Risks

    Science.gov (United States)

    ... that creatine may have some athletic benefit by producing small gains in short-term bursts of power. ... 2015 Original article: http://www.mayoclinic.org/healthy-lifestyle/fitness/in-depth/performance-enhancing-drugs/art-20046134 . ...

  10. Serial magnetic resonance imaging of acute disseminated encephalomyelitis, including evaluation of the contrast-enhancing effect on lesions by Gd-DTPA

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, Yasunori; Matsuo, Michimasa [Tenri Hospital, Nara (Japan). MR Center

    1996-01-01

    Many papers on the MR features of acute disseminated encephalomyelitis (ADEM) have been published, but only a few described contrast-enhanced MRI for this disease. In this study, we analyzed serial changes in MR features and the contrast-enhancing effect on lesions in five patients (5 men, 4-19 years old) discharged with the final diagnosis of ADEM. Hyperintense lesions in brain/spinal cord were demonstrated on T2-weighted MR images in all cases, but not all lesions were enhanced by Gd-DTPA. In the follow-up study many lesions disappeared, but some lesions were enlarged and some new lesions were found. These findings suggest that, although ADEM is clinically monophasic, some cases may progress with the coexistence of reducing, vanishing, and new lesions. Some clinically acute lesions were not enhanced. This might be explained by the following reasons; lesions on various phases coexist, the damage to the blood-brain barrier in the lesions is of different degrees even if it is on the same phase, and the duration of acute phase activity is short. Additionally, some hyperintense lesions remained for a long time on T2-weighted images in spite of the absence of clinical manifestation. That hyperintense area might reflect edema caused by incomplete repair of the blood-brain barrier. From our evaluation of these five cases, MRI is not useful for the diagnosis and follow-up study of ADEM. (author).

  11. Enhancing Organizational Performance: A Toolbox for Self ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Do you know if your organization is performing efficiently? If it isn't, do you know why? This guidebook presents an innovative and thoroughly tested model for organizational self-assessment. The tools and tips in Enhancing Organizational Performance go beyond measuring the impact of programs, products, and services.

  12. The clinical impact of late gadolinium enhancement in Takotsubo cardiomyopathy: serial analysis of cardiovascular magnetic resonance images

    Directory of Open Access Journals (Sweden)

    Katoh Hideki

    2011-10-01

    Full Text Available Abstract Background Our study aimed to investigate both the clinical implications of late gadolinium enhancement (LGE by cardiovascular magnetic resonance (CMR and the relation of LGE to clinical findings in patients with Takotsubo cardiomyopathy (TTC. Methods We evaluated 20 consecutive patients (2 men, 18 women; median age, 77 years; interquartile range [IQR] 67-82 years who were admitted to our hospital with the diagnosis of TTC. CMR was performed within 1 week after admission, and follow-up studies were conducted 1.5 and 6 months later. Results In 8 patients, CMR imaging during the sub-acute phase revealed LGE in the area matched with wall motion impairment. Cardiogenic shock was more frequently observed in patients with LGE than in those without LGE (38% vs 0%, p = 0.049. The patients with LGE needed a longer duration for ECG normalization and recovery of wall motion than did those without LGE (median 205 days, IQR [152-363] vs 68 days, [43-145], p = 0.005; 15 days, [10-185] vs 7 days, [4-13], p = 0.030, respectively. In 5 of these 8 patients, LGE disappeared within 45-180 days (170, IQR [56-180] of onset. The patients with LGE remaining in the chronic phase had higher peak creatine kinase levels than did those without LGE (median 307 IU/L, IQR [264-460] vs 202 IU/L, [120-218], p = 0.017. Conclusion LGE by CMR in the sub-acute phase may be associated with the severity and prolonged recovery to normal of clinical findings in TTC.

  13. Enhanced expectancies improve performance under pressure

    Directory of Open Access Journals (Sweden)

    Brad eMcKay

    2012-01-01

    Full Text Available Beyond skill, beliefs in requisite abilities and expectations can affect performance. This study examined effects of induced perceptions of ability to perform well under generic situations of challenge. Participants (N = 31 first completed one block of 20 trials on a throwing accuracy task. They then completed questionnaires ostensibly measuring individual differences in the ability to perform under pressure. Enhanced-expectancy group participants were told that they were well-suited to perform under pressure, while the control group received neutral information. Subsequently, all participants completed another block of 20 trials on the throwing task, with their performance being videotaped and under the assumption that they could secure a prize for themselves and a paired participant with successful performance. Both groups had similar accuracy scores on the first trial block. The enhanced-expectancy group significantly increased their throwing accuracy in the high-pressure situation (second block, whereas the control group showed no change in performance. Furthermore, beliefs regarding performance under challenge predicted throwing accuracy on the second block. The present findings provide evidence that enhancing individuals’ generic expectancies regarding performance under pressure can affect their motor performance.

  14. The Productivity Advantage of Serial Entrepreneurs

    DEFF Research Database (Denmark)

    Shaw, Kathryn L.; Sørensen, Anders

    Serial entrepreneurs, who open more than one business, are found to have higher sales and higher productivity than novice entrepreneurs, who open one business. Using panel data on entrepreneurs and their firms from Denmark for 2001-2013, the serial entrepreneur has 67% higher sales than the novic...... firm rather than proprietorships. Female serial entrepreneurs do as well as male serial entrepreneurs relative to the performance of novices of their own genders. The second firms of the serial entrepreneurs also stay in business longer than the first (and only) firms of the novices....

  15. Output order in immediate serial recall.

    Science.gov (United States)

    Tan, Lydia; Ward, Geoff

    2007-07-01

    In two experiments, we examined the effect of output order in immediate serial recall (ISR). In Experiment 1, three groups of participants saw lists of eight words and wrote down the words in the rows corresponding to their serial positions in an eight-row response grid. One group was precued to respond in forward order, a second group was precued to respond in any order, and a third group was postcued for response order. There were significant effects of output order, but not of cue type. Relative to the forward output order, the free output order led to enhanced recency and diminished primacy, with superior performance for words output early in recall. These results were replicated in Experiment 2 using six-item lists, which further suggests that output order plays an important role in the primacy effect in ISR and that the recency items are most highly accessible at recall.

  16. Acute myocardial infarction: serial cardiac MR imaging shows a decrease in delayed enhancement of the myocardium during the 1st week after reperfusion.

    Science.gov (United States)

    Ibrahim, Tareq; Hackl, Thomas; Nekolla, Stephan G; Breuer, Martin; Feldmair, Michael; Schömig, Albert; Schwaiger, Markus

    2010-01-01

    To evaluate the time course of delayed gadolinium enhancement of infarcted myocardium by using serial contrast agent-enhanced (CE) cardiac magnetic resonance (MR) images obtained during the acute, subacute, and chronic stages of infarction. The study protocol was reviewed and approved by the local ethics committee, and written informed consent was obtained. Seventeen patients with reperfused acute myocardial infarction (AMI) underwent cine and CE cardiac MR a median of 1, 7, 35, and 180 days after reperfusion. Infarct size determined on the basis of delayed enhancement MR imaging at different times was compared by using nonparametric tests and Bland-Altman analysis. Extent of myocardial enhancement was compared with single photon emission computed tomographic (SPECT) measures of infarct size with Spearman correlation. Regional myocardial enhancement extent and contractility were analyzed with nonparametric tests. Infarct size was 18.3% of total myocardial LV volume on day 1 after AMI and decreased to 12.9% on day 7, 11.3% on day 35, and 11.6% on day 180 (all P infarct size on day 7, as compared with day 1 enhancement size, declined by 57.1% within the epicardium and by 6.3% within the endocardium (both P Infarct size on day 7 showed only minor changes at subsequent imaging and yielded a high correlation with SPECT measurements of infarct size (r = 0.84). Infarct size on day 7 inversely correlated with long-term wall thickening (P infarction. Thus, timing of CE cardiac MR imaging is crucial for accurate measurement of myocardial infarct size early after AMI.

  17. The effects of task-relevant saccadic eye movements performed during the encoding of a serial sequence on visuospatial memory performance.

    Science.gov (United States)

    Martin, Leonardo; Tapper, Anthony; Gonzalez, David A; Leclerc, Michelle; Niechwiej-Szwedo, Ewa

    2017-05-01

    Visuospatial working memory (VSWM) is a set of cognitive processes used to encode, maintain and manipulate spatial information. One important feature of VSWM is that it has a limited capacity such that only few items can be actively stored and manipulated simultaneously. Given the limited capacity, it is important to determine the conditions that affect memory performance as this will improve our understanding of the architecture and function of VSWM. Previous studies have shown that VSWM is disrupted when task-irrelevant eye movements are performed during the maintenance phase; however, relatively fewer studies examined the role of eye movements performed during the encoding phase. On one hand, performing eye movements during the encoding phase could result in a stronger memory trace because the memory formation is reinforced by the activation of the motor system. On the other hand, performing eye movements to each target could disrupt the configural processing of the spatial array because the spatial representation has to be updated with each movement to maintain perceptual stability. Therefore, this work was conducted to examine whether task-relevant saccadic eye movements performed during the encoding phase of a visuospatial working memory task affect the recall of serially presented targets. Results from two experiments showed that average recall accuracy was significantly higher when the spatial array (set size ≥ 7) was encoded using a covert strategy-that is, while participants fixated on a central target, in comparison to an overt strategy-that is, while participants moved their eyes to fixate on each target. Furthermore, the improvement in accuracy was evident only for targets presented in the first half of the sequence, suggesting that the primacy effect is modulated by the presence of eye movements. We propose that executing saccades during encoding could interfere with the ability to use a chunking strategy or disrupt active visualization of the

  18. Serial Branches

    DEFF Research Database (Denmark)

    Schindler, Christoph; Tamke, Martin; Tabatabai, Ali

    2013-01-01

    Within a 8-day workshop 19 students of KADK explored the performative potential of naturally angled and forked wood – a desired material until 19th century, but swept away by industrialization and its standardization of processes and materials. The workshop questioned whether contemporary informa...... information technology with its potential for individual fabrication allows for a new approach to the uniqueness that is offered to us by nature....

  19. Performance management system enhancement and maintenance

    Science.gov (United States)

    Cleaver, T. G.; Ahour, R.; Johnson, B. R.

    1984-01-01

    The research described in this report concludes a two-year effort to develop a Performance Management System (PMS) for the NCC computers. PMS provides semi-automated monthly reports to NASA and contractor management on the status and performance of the NCC computers in the TDRSS program. Throughout 1984, PMS was tested, debugged, extended, and enhanced. Regular PMS monthly reports were produced and distributed. PMS continues to operate at the NCC under control of Bendix Corp. personnel.

  20. managing reward strategy to enhance employee performance ...

    African Journals Online (AJOL)

    Prof

    compensation structure. The application of these notions when matched with a good managerial disposition will enable organizations to formulate effective, sustainable strategies that will address equitable and adequate reward for employees, which in turn will enhance employees' performance, retention and productivity in ...

  1. Performance-Enhancing Drugs and Teen Athletes

    Science.gov (United States)

    ... http://www.hormone.org/questions-and-answers/2012/supplements-steroid-precursors-and-adolescent-health. Accessed Feb. 17, 2015. Harris SS, et al. Performance-enhancing substances. In.: Care of the Young Athlete. 2nd ed. Elk Grove Village, Ill.: American Academy ...

  2. Learning, remembering, believing: enhancing human performance

    National Research Council Canada - National Science Library

    Druckman, Daniel; Bjork, Robert A

    1994-01-01

    ... for the Enhancement of Human Performance Commission on Behavioral and Social Sciences and Education National Research Council NATIONAL ACADEMY PRESS Washington, D.C. 1994 Copyrightthe cannot be not from book, paper however, version for formatting, original authoritative the typesetting-specific the as from created publication files XM...

  3. Peripheral visual performance enhancement by neurofeedback training.

    Science.gov (United States)

    Nan, Wenya; Wan, Feng; Lou, Chin Ian; Vai, Mang I; Rosa, Agostinho

    2013-12-01

    Peripheral visual performance is an important ability for everyone, and a positive inter-individual correlation is found between the peripheral visual performance and the alpha amplitude during the performance test. This study investigated the effect of alpha neurofeedback training on the peripheral visual performance. A neurofeedback group of 13 subjects finished 20 sessions of alpha enhancement feedback within 20 days. The peripheral visual performance was assessed by a new dynamic peripheral visual test on the first and last training day. The results revealed that the neurofeedback group showed significant enhancement of the peripheral visual performance as well as the relative alpha amplitude during the peripheral visual test. It was not the case in the non-neurofeedback control group, which performed the tests within the same time frame as the neurofeedback group but without any training sessions. These findings suggest that alpha neurofeedback training was effective in improving peripheral visual performance. To the best of our knowledge, this is the first study to show evidence for performance improvement in peripheral vision via alpha neurofeedback training.

  4. Enhanced performance for the manned maneuvering unit

    Science.gov (United States)

    Bingham, Paul E.

    We have all seen the Manned Maneuvering Unit (MMU) on television, in the newspaper, magazines and any number of other places. It is probably one of the most widely recognized articles ever put into orbit. This paper briefly describes the MMU. The description includes an overview of the controls and physical features and a discussion of the propulsion and electrical systems. Operational experience to date is briefly covered. The MMU was first used on STS 41-B for the first untethered space walk on February 7, 1984. Next usage was for the Solar Max mission on STS 41-C, followed by the retrieval of the Westar and Palapa communication satellites on mission STS 51-A in November, 1984. One of the "lessons learned" during these space operations was the need for enhanced performance by the MMU, and leads into a discussion of how that increased performance capability will be provided. Current work on a Propellant Tank Kit (PTK), which will provide enhanced performance, is shown. The PTK will provide sufficient propellant storage capability such that the MMU with PTK will have twice the previous delta velocity capability; i.e., double the MMU's maneuvering ability. Results of development testing in the NASA/JSC Weightless Environment Test Facility are included. Current status of PTK development is presented. This paper ends with a brief discussion of proposed space operations using the enhanced MMU performance in erecting space structures from the Space Shuttle, assembling and maintaining Space Station, rescue-transfer of astronauts and other space operations.

  5. Decreasing serial cost sharing

    DEFF Research Database (Denmark)

    Hougaard, Jens Leth; Østerdal, Lars Peter Raahave

    2009-01-01

    The increasing serial cost sharing rule of Moulin and Shenker (Econometrica 60:1009-1037, 1992) and the decreasing serial rule of de Frutos (J Econ Theory 79:245-275, 1998) are known by their intuitive appeal and striking incentive properties. An axiomatic characterization of the increasing serial...

  6. Performance-enhancing drugs: understanding the risks.

    Science.gov (United States)

    Hatton, Caroline K; Green, Gary A; Ambrose, Peter J

    2014-11-01

    To help clinicians understand the risks associated with performance-enhancing drugs, this overview covers prohibited lists of substances and methods, therapeutic use exemptions, the legitimate indications and adverse effects, including for megadose and polypharmacy doping of stimulants, anabolic steroids, erythropoiesis-stimulating agents, and growth hormone and ways in which physicians or patients risk committing anti-doping rule violations inadvertently. Copyright © 2014 Elsevier Inc. All rights reserved.

  7. Enhancing an enterprise's innovation performance measurement system

    OpenAIRE

    Stanković, Ljiljana; Novićević, Blagoje; Đukić, Suzana

    2011-01-01

    Business conditions under which modern enterprises operate are becoming more and more complex. The complexity of the business environment is caused not only by external but also by internal factors, which imposes the need for turnover in management focus. The turnover is reflected primarily in the change of business models. The changes are evident at all management stages. Development and enhancement of business performance measurement system is the area where the changes are most evident con...

  8. A meta-analysis and meta-regression of serial reaction time task performance in Parkinson's disease.

    Science.gov (United States)

    Clark, Gillian M; Lum, Jarrad A G; Ullman, Michael T

    2014-11-01

    This article reports findings of a meta-analysis and meta-regression summarizing research on implicit sequence learning in individuals with Parkinson's disease (PD), as measured by the Serial Reaction Time (SRT) task. Following a systematic search of the literature, we analyzed a total of 27 studies, representing data from 505 participants with PD and 460 neurologically intact control participants. Overall, the meta-analysis indicated significantly (p < .001) worse sequence learning by the PD group than the control group. The average weighted effect size was found to be .531 (95% CI [.332, .470]), which is a medium effect size. However, moderate to high levels of heterogeneity (differences) were found between study effect sizes (I(2) = 58%). Meta-regression analysis suggested that presentation of the SRT task under dual task conditions coupled with PD severity or characteristics of the sequence might affect study effect sizes. The meta-analysis provides clear support that learning in procedural memory (procedural learning), which underlies implicit sequence learning in the SRT task, is impaired in PD. PsycINFO Database Record (c) 2014 APA, all rights reserved.

  9. Serial or overlapping processing in multitasking as individual preference: Effects of stimulus preview on task switching and concurrent dual-task performance.

    Science.gov (United States)

    Reissland, Jessika; Manzey, Dietrich

    2016-07-01

    Understanding the mechanisms and performance consequences of multitasking has long been in focus of scientific interest, but has been investigated by three research lines more or less isolated from each other. Studies in the fields of the psychological refractory period, task switching, and interruptions have scored with a high experimental control, but usually do not give participants many degrees of freedom to self-organize the processing of two concurrent tasks. Individual strategies as well as their impact on efficiency have mainly been neglected. Self-organized multitasking has been investigated in the field of human factors, but primarily with respect to overall performance without detailed investigation of how the tasks are processed. The current work attempts to link aspects of these research lines. All of them, explicitly or implicitly, provide hints about an individually preferred type of task organization, either more cautious trying to work strictly serially on only one task at a time or more daring with a focus on task interleaving and, if possible, also partially overlapping (parallel) processing. In two experiments we investigated different strategies of task organization and their impact on efficiency using a new measure of overall multitasking efficiency. Experiment 1 was based on a classical task switching paradigm with two classification tasks, but provided one group of participants with a stimulus preview of the task to switch to next, enabling at least partial overlapping processing. Indeed, this preview led to a reduction of switch costs and to an increase of dual-task efficiency, but only for a subgroup of participants. They obviously exploited the possibility of overlapping processing, while the others worked mainly serially. While task-sequence was externally guided in the first experiment, Experiment 2 extended the approach by giving the participants full freedom of task organization in concurrent performance of the same tasks. Fine

  10. Lean Production Practices to Enhance Organisational Performance

    Directory of Open Access Journals (Sweden)

    Shah Satya

    2017-01-01

    Full Text Available Service sector organisations are constantly overcoming the challenges facing the over-production and waste reduction within their environments. Industries are also becoming very competitive thus forcing them to seek suitable production organisation strategies with the aim towards enhancing their competitiveness and efficiency. The aim of this research study is to investigate the impact of lean production practices on the performance of service based businesses through the case study of a local baked goods supplier. The research framework adopted consists of questionnaire survey method implemented with different end users, thus covering the overall production – retail – customer cycle. The research results and analysis justify the objective of the research that lean production practices enhance the performance of the supplier company and the common tool identified were JIT (Just in Time, Value Steam Mapping (VSP and the 5S methods. The results also suggest that JIT method has a higher impact towards improvement on performance relating to quality, speed, dependability, flexibility and cost of the supplier. However, the research study also identifies that one of the major challenges faced by the organisation while adopting lean practices was the lack of commitment from top management, continuous training and employee engagement measures.

  11. Reframing Serial Murder Within Empirical Research.

    Science.gov (United States)

    Gurian, Elizabeth A

    2017-04-01

    Empirical research on serial murder is limited due to the lack of consensus on a definition, the continued use of primarily descriptive statistics, and linkage to popular culture depictions. These limitations also inhibit our understanding of these offenders and affect credibility in the field of research. Therefore, this comprehensive overview of a sample of 508 cases (738 total offenders, including partnered groups of two or more offenders) provides analyses of solo male, solo female, and partnered serial killers to elucidate statistical differences and similarities in offending and adjudication patterns among the three groups. This analysis of serial homicide offenders not only supports previous research on offending patterns present in the serial homicide literature but also reveals that empirically based analyses can enhance our understanding beyond traditional case studies and descriptive statistics. Further research based on these empirical analyses can aid in the development of more accurate classifications and definitions of serial murderers.

  12. Serial Order: A Parallel Distributed Processing Approach.

    Science.gov (United States)

    Jordan, Michael I.

    Human behavior shows a variety of serially ordered action sequences. This paper presents a theory of serial order which describes how sequences of actions might be learned and performed. In this theory, parallel interactions across time (coarticulation) and parallel interactions across space (dual-task interference) are viewed as two aspects of a…

  13. Benchmarking: A tool to enhance performance

    Energy Technology Data Exchange (ETDEWEB)

    Munro, J.F. [Oak Ridge National Lab., TN (United States); Kristal, J. [USDOE Assistant Secretary for Environmental Management, Washington, DC (United States); Thompson, G.; Johnson, T. [Los Alamos National Lab., NM (United States)

    1996-12-31

    The Office of Environmental Management is bringing Headquarters and the Field together to implement process improvements throughout the Complex through a systematic process of organizational learning called benchmarking. Simply stated, benchmarking is a process of continuously comparing and measuring practices, processes, or methodologies with those of other private and public organizations. The EM benchmarking program, which began as the result of a recommendation from Xerox Corporation, is building trust and removing barriers to performance enhancement across the DOE organization. The EM benchmarking program is designed to be field-centered with Headquarters providing facilitatory and integrative functions on an ``as needed`` basis. One of the main goals of the program is to assist Field Offices and their associated M&O/M&I contractors develop the capabilities to do benchmarking for themselves. In this regard, a central precept is that in order to realize tangible performance benefits, program managers and staff -- the ones closest to the work - must take ownership of the studies. This avoids the ``check the box`` mentality associated with some third party studies. This workshop will provide participants with a basic level of understanding why the EM benchmarking team was developed and the nature and scope of its mission. Participants will also begin to understand the types of study levels and the particular methodology the EM benchmarking team is using to conduct studies. The EM benchmarking team will also encourage discussion on ways that DOE (both Headquarters and the Field) can team with its M&O/M&I contractors to conduct additional benchmarking studies. This ``introduction to benchmarking`` is intended to create a desire to know more and a greater appreciation of how benchmarking processes could be creatively employed to enhance performance.

  14. Use of Performance-Enhancing Substances.

    Science.gov (United States)

    LaBotz, Michele; Griesemer, Bernard A

    2016-07-01

    Performance-enhancing substances (PESs) are used commonly by children and adolescents in attempts to improve athletic performance. More recent data reveal that these same substances often are used for appearance-related reasons as well. PESs include both legal over-the-counter dietary supplements and illicit pharmacologic agents. This report reviews the current epidemiology of PES use in the pediatric population, as well as information on those PESs in most common use. Concerns regarding use of legal PESs include high rates of product contamination, correlation with future use of anabolic androgenic steroids, and adverse effects on the focus and experience of youth sports participation. The physical maturation and endogenous hormone production that occur in adolescence are associated with large improvements in strength and athletic performance. For most young athletes, PES use does not produce significant gains over those seen with the onset of puberty and adherence to an appropriate nutrition and training program. Copyright © 2016 by the American Academy of Pediatrics.

  15. PRODUCTION WELL PERFORMANCE ENHANCEMENT USING SONICATION TECHNOLOGY

    Energy Technology Data Exchange (ETDEWEB)

    Michael A. Adewumi; M. Thaddeus Ityokumbul; Robert W. Watson; Mario Farias; Glenn Heckman; Johnson Olanrewaju; Eltohami Eltohami; Bruce G. Miller; W. Jack Hughes; Thomas C. Montgomery

    2003-12-17

    The objective of this project is to develop a sonic well performance enhancement technology that focuses on near wellbore formations. In order to successfully achieve this objective, a three-year project has been defined with each year consisting of four tasks. The first task is the laboratory-scale study whose goal is to determine the underlying principles of the technology. The second task will develop a scale-up mathematical model to serve as the design guide for tool development. The third task is to develop effective transducers that can operate with variable frequency so that the most effective frequencies can be applied in any given situation. The system, assembled as part of the production string, ensures delivery of sufficient sonic energy to penetrate the near-wellbore formation. The last task is the actual field testing of the tool. The first year of the project has been completed.

  16. Manually Maintained Serials Records.

    Science.gov (United States)

    Ortopan, LeRoy D.; And Others

    At the American Library Association Annual Conference in Dallas in 1971, the Serials Section of the Resources and Technical Services Division established a committee to produce a state-of-the-art report on the maintenance of serial records by manual methods in all types of libraries. The Ad Hoc Committee to Study Manually Maintained Serials…

  17. Serial action and perception

    NARCIS (Netherlands)

    Abrahamse, E.L.

    2010-01-01

    The central theme of this dissertation concerns the nature of (implicit) perceptual-motor sequence learning as studied in the serial reaction time (SRT) task. Convincing support exists in the literature for three forms of serial learning: perceptual learning (S-S associations), response-based

  18. Decreasing Serial Cost Sharing

    DEFF Research Database (Denmark)

    Hougaard, Jens Leth; Østerdal, Lars Peter

    The increasing serial cost sharing rule of Moulin and Shenker [Econometrica 60 (1992) 1009] and the decreasing serial rule of de Frutos [Journal of Economic Theory 79 (1998) 245] have attracted attention due to their intuitive appeal and striking incentive properties. An axiomatic characterization...

  19. Enhanced performance of quantum cascade Raman laser

    Science.gov (United States)

    Yousefvand, Hossein Reza; Aahmadi, Vahid

    2015-05-01

    We present a self-consistent numerical approach for quantum cascade Raman laser (QC-RL) with a modified design to improve the device performance. Our modeling approach is based on monolithic integration of stimulated Raman scattering (SRS) and electrically pumped QC laser. The laser band structure utilizing techniques with both material-dependent effective mass and band nonparabolicity is calculated by solving the Schrodinger-Poisson equations self-consistently. A detailed analysis of output characteristics of the obtained structure is carried out within a simplified 4-level rate equations model taking into account the SRS process. The model accurately explains the operating characteristics found in QCLs, such as damping transient response and non-resonant behavior of modulation frequency response. Furthermore, modification of the structure is focused on improving the SRS in the QC-RL. This leads to an enhancement of the device performance such as threshold current, external quantum efficiency, conversion efficiency, turn-on delay and modulation response. The excellent agreement of the experimental data with the simulated light output-current characteristics confirms the validity of the model.

  20. Enhancement of thermal performance in KRS buffer

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Jong Won; Lee, Jong Youl; Kim, Geon Young; Lee, Yang; Koo, J. E

    2007-03-15

    The Korean Reference disposal System consists of the engineered barrier and natural barrier. The main components of the engineered barrier are the canister and buffer. KAERI has developed the buffer for the repository. So far Korean domestic Ca-bentonite was selected as buffer material and the properties of it were characterized. In this report the design requirements of the buffer are fixed based on the characteristics of Korean Ca-bentonite, and the conceptual design of the buffer for KRS is carried out by determining the thickness and shape of the buffer. The thickness of 0.5 m buffer is determined from the mass transfer equation, which gives the less radionuclide release rates from the borehole to the rock. The shape of the buffer is disk and ring. The dry density is 1.6 g/cm{sup 3}. The thickness of the buffer above the canister is 2.5 m and the that of the buffer below the canister is 0.5 m. The disposal system should meet the requirement that the maximum temperature at the interface between the buffer and the canister keeps below 100 .deg.. A 3-dimensional finite element program is used for the thermal analysis around the buffer. The results shows that the current conceptual design of the buffer meets the requirement. Another major role of the buffer is to protect the canister and the spent fuels from the exterior impact. The rock movement around the buffer is introduced to assess the buffer performance. Two cases of rock movement are assessed, and the results show that the buffer mitigates sufficiently the impact from the 10 cm movement of rock. Finally, the resaturation time is estimated through mathematical modeling. ABAQUS program is used for the analysis, and the resaturation time is estimated to be around 10 to 30 years. The enhancement of thermal performance of the disposal system is directly related to the economics of the HLW disposal. The way to enhance the thermal performance is suggested from the results of experiment and design. The thermal

  1. Serial Network Flow Monitor

    Science.gov (United States)

    Robinson, Julie A.; Tate-Brown, Judy M.

    2009-01-01

    Using a commercial software CD and minimal up-mass, SNFM monitors the Payload local area network (LAN) to analyze and troubleshoot LAN data traffic. Validating LAN traffic models may allow for faster and more reliable computer networks to sustain systems and science on future space missions. Research Summary: This experiment studies the function of the computer network onboard the ISS. On-orbit packet statistics are captured and used to validate ground based medium rate data link models and enhance the way that the local area network (LAN) is monitored. This information will allow monitoring and improvement in the data transfer capabilities of on-orbit computer networks. The Serial Network Flow Monitor (SNFM) experiment attempts to characterize the network equivalent of traffic jams on board ISS. The SNFM team is able to specifically target historical problem areas including the SAMS (Space Acceleration Measurement System) communication issues, data transmissions from the ISS to the ground teams, and multiple users on the network at the same time. By looking at how various users interact with each other on the network, conflicts can be identified and work can begin on solutions. SNFM is comprised of a commercial off the shelf software package that monitors packet traffic through the payload Ethernet LANs (local area networks) on board ISS.

  2. Minimally Actuated Serial Robot

    OpenAIRE

    Mann, Moshe P.; Damti, Lior; Zarrouk, David

    2017-01-01

    In this paper, we propose a novel type of serial robot with minimal actuation. The robot is a serial rigid structure consisting of multiple links connected by passive joints and of movable actuators. The novelty of this robot is that the actuators travel over the links to a given joint and adjust the relative angle between the two adjacent links. The joints passively preserve their angles until one of the actuators moves them again. This actuation can be applied to any serial robot with two o...

  3. Production Well Performance Enhancement using Sonication Technology

    Energy Technology Data Exchange (ETDEWEB)

    Adewumi, Michael A; Ityokumbul, M Thaddeus; Watson, Robert W; Eltohami, Eltohami; Farias, Mario; Heckman, Glenn; Houlihan, Brendan; Karoor, Samata Prakash; Miller, Bruce G; Mohammed, Nazia; Olanrewaju, Johnson; Ozdemir, Mine; Rejepov, Dautmamed; Sadegh, Abdallah A; Quammie, Kevin E; Zaghloul, Jose; Hughes, W Jack; Montgomery, Thomas C

    2005-12-31

    The objective of this project was to develop a sonic well performance enhancement technology that focused on near wellbore formation damage. In order to successfully achieve this objective, a three-year project was defined. The entire project was broken into four tasks. The overall objective of all this was to foster a better understanding of the mechanisms involved in sonic energy interactions with fluid flow in porous media and adapt such knowledge for field applications. The fours tasks are: • Laboratory studies • Mathematical modeling • Sonic tool design and development • Field demonstration The project was designed to be completed in three years; however, due to budget cuts, support was only provided for the first year, and hence the full objective of the project could not be accomplished. This report summarizes what was accomplished with the support provided by the US Department of Energy. Experiments performed focused on determining the inception of cavitation, studying thermal dissipation under cavitation conditions, investigating sonic energy interactions with glass beads and oil, and studying the effects of sonication on crude oil properties. Our findings show that the voltage threshold for onset of cavitation is independent of transducer-hydrophone separation distance. In addition, thermal dissipation under cavitation conditions contributed to the mobilization of deposited paraffins and waxes. Our preliminary laboratory experiments suggest that waxes are mobilized when the fluid temperature approaches 40°C. Experiments were conducted that provided insights into the interactions between sonic wave and the fluid contained in the porous media. Most of these studies were carried out in a slim-tube apparatus. A numerical model was developed for simulating the effect of sonication in the nearwellbore region. The numerical model developed was validated using a number of standard testbed problems. However, actual application of the model for scale

  4. Classifying serial killers.

    Science.gov (United States)

    Promish, D I; Lester, D

    1999-11-08

    We attempted to match the appearance and demeanor of 27 serial killers to the postmortem 'signatures' found on their victims' bodies. Our results suggest that a link may exist between postmortem signatures and two complementary appearance-demeanor types.

  5. Playing at Serial Acquisitions

    NARCIS (Netherlands)

    J.T.J. Smit (Han); T. Moraitis (Thras)

    2010-01-01

    textabstractBehavioral biases can result in suboptimal acquisition decisions-with the potential for errors exacerbated in consolidating industries, where consolidators design serial acquisition strategies and fight escalating takeover battles for platform companies that may determine their future

  6. Epithelial atypia in biopsies performed for microcalcifications. practical considerations about 2,833 serially sectioned surgical biopsies with a long follow-up.

    Science.gov (United States)

    de Mascarel, Isabelle; MacGrogan, Gaëtan; Mathoulin-Pélissier, Simone; Vincent-Salomon, Anne; Soubeyran, Isabelle; Picot, Véronique; Coindre, Jean-Michel; Mauriac, Louis

    2007-07-01

    This study analyzes the occurrence of epithelial atypia in 2,833 serially sectioned surgical breast biopsies (SB) performed for microcalcifications (median number of blocks per SB:26) and the occurrence of subsequent cancer after an initial diagnosis of epithelial atypia (median follow-up 160 months). Epithelial atypia (flat epithelial atypia, atypical ductal hyperplasia, and lobular neoplasia) were found in 971 SB, with and without a concomitant cancer in 301 (31%) and 670 (69%) SB, respectively. Thus, isolated epithelial atypia were found in 670 out of the 2,833 SB (23%). Concomitant cancers corresponded to ductal carcinomas in situ and micro-invasive (77%), invasive ductal carcinomas not otherwise specified (15%), invasive lobular carcinomas (4%), and tubular carcinomas (4%). Fifteen out of the 443 patients with isolated epithelial atypia developed a subsequent ipsilateral (n = 14) and contralateral (n = 1) invasive cancer. The high slide rating might explain the high percentages of epithelial atypia and concomitant cancers and the low percentage of subsequent cancer after a diagnosis of epithelial atypia as a single lesion. Epithelial atypia could be more a risk marker of concomitant than subsequent cancer.

  7. SOCIAL PERFORMANCE ENHANCES FINANCIAL PERFORMANCE. BENEFITS FROM CSR

    Directory of Open Access Journals (Sweden)

    gazzola patrizia

    2012-07-01

    Full Text Available The research aims to show how Corporate Social Responsibility (CSR should not be considered a cost to bear as an economic social actor but an investment that will contribute to the competitiveness and growth of the firm. In the first part we consider capitalistic firm as systems for the creation of economic and financial value for their shareholders. We measure their performance by a system of monetary values. In the second part we do not limit our view to simply the shareholders, but we consider, instead a vast group of stakeholders because it is important not only to make profits, but also how companies make them . In these years characterized by the financial crisis, where many big companies went bankrupt, more and more companies are speaking about ethics and CSR. For a firm, acting socially responsible, means for example having fair compensations, promoting transparency and the respect of employees, neutralizing conflicts of interest, as well as taking care of the environment. CSR is today a topic for discussion not only for business people but also for politicians, media, researchers, NGOs and consumers. Growing awareness of CSR is evident in the growth of voluntary codes of corporate conduct, in the growth of companies that are using self-reporting on social and environmental practices, and in increasingly social and ethical investment funds. The public and governments of the world have been steadily increasing pressure on corporations to increase their CSR. Recently the European Commission has put forward a new, simpler definition of corporate social responsibility as “the responsibility of enterprises for their impacts on society” (European Commission 25/10/2011. Companies have realized that to increase their market share or keep their market share, they must adopt CSR, but the synergy between social performance and financial performance is not automatic; rather it is the result of efforts that combine managerial

  8. Novel biofuel formulations for enhanced vehicle performance

    Energy Technology Data Exchange (ETDEWEB)

    Miller, Dennis [Michigan State Univ., East Lansing, MI (United States); Narayan, Ramani [Michigan State Univ., East Lansing, MI (United States); Berglund, Kris [Michigan State Univ., East Lansing, MI (United States); Lira, Carl [Michigan State Univ., East Lansing, MI (United States); Schock, Harold [Michigan State Univ., East Lansing, MI (United States); Jaberi, Farhad [Michigan State Univ., East Lansing, MI (United States); Lee, Tonghun [Michigan State Univ., East Lansing, MI (United States); Anderson, James [Michigan State Univ., East Lansing, MI (United States); Wallington, Timothy [Michigan State Univ., East Lansing, MI (United States); Kurtz, Eric [Michigan State Univ., East Lansing, MI (United States); Ruona, Will; Hass, Heinz

    2013-08-30

    This interdisciplinary research program at Michigan State University, in collaboration with Ford Motor Company, has explored the application of tailored or designed biofuels for enhanced vehicle performance and reduced emissions. The project has included a broad range of experimental research, from chemical and biological formation of advanced biofuel components to multicylinder engine testing of blended biofuels to determine engine performance parameters. In addition, the project included computation modeling of biofuel physical and combustion properties, and simulation of advanced combustion modes in model engines and in single cylinder engines. Formation of advanced biofuel components included the fermentation of five-carbon and six-carbon sugars to n-butanol and to butyric acid, two four-carbon building blocks. Chemical transformations include the esterification of the butyric acid produced to make butyrate esters, and the esterification of succinic acid with n-butanol to make dibutyl succinate (DBS) as attractive biofuel components. The conversion of standard biodiesel, made from canola or soy oil, from the methyl ester to the butyl ester (which has better fuel properties), and the ozonolysis of biodiesel and the raw oil to produce nonanoate fuel components were also examined in detail. Physical and combustion properties of these advanced biofuel components were determined during the project. Physical properties such as vapor pressure, heat of evaporation, density, and surface tension, and low temperature properties of cloud point and cold filter plugging point were examined for pure components and for blends of components with biodiesel and standard petroleum diesel. Combustion properties, particularly emission delay that is the key parameter in compression ignition engines, was measured in the MSU Rapid Compression Machine (RCM), an apparatus that was designed and constructed during the project simulating the compression stroke of an internal combustion

  9. Acoustic trauma that can cause tinnitus impairs impulsive control but not performance accuracy in the 5-choice serial reaction time task in rats.

    Science.gov (United States)

    Zheng, Y; Hamilton, E; Stiles, L; McNamara, E; de Waele, C; Smith, P F; Darlington, C L

    2011-04-28

    Although tinnitus is an auditory disorder, it is often associated with attentional and emotional problems. Functional neuroimaging studies in humans have revealed that the hippocampus, amygdala and anterior cingulate, areas of the brain involved in emotion, attention and spatial processing, are also involved in auditory memory and tinnitus perception. However, few studies of tinnitus-evoked emotional and cognitive changes have been reported using animal models of tinnitus. In the present study, we investigated whether acoustic trauma that could cause tinnitus would affect attention and impulsivity in rats. Eight male Wistar rats were exposed to unilateral acoustic trauma (110 dB, 16 kHz for 1 h under anaesthesia) and eight rats underwent the same anaesthesia without acoustic trauma. Tinnitus was tested in noise-exposed rats using a frequency-specific shift in a discrimination function with a conditioned lick suppression paradigm. At 4 months after the noise exposure, the rats were tested in a 5-choice serial reaction time task. The behavioural procedure involved training the rats to discriminate a brief visual stimulus presented randomly in one of the five spatial locations and responding by poking its nose through the illuminated hole and collecting a food pellet from the magazine. While all of the animals performed equally well in making correct responses, the animals exposed to acoustic trauma made significantly more premature responses. The results suggest that rats exposed to acoustic trauma and some of which have chronic tinnitus are impaired in impulsive control, but not performance accuracy. Copyright © 2011 IBRO. Published by Elsevier Ltd. All rights reserved.

  10. The Windows serial port programming handbook

    CERN Document Server

    Bai, Ying

    2004-01-01

    The fundamentals of serial port communications. Serial port programming in ANSI C and Assembly languages for MS-DOS. Serial ports interface developed in VC++ 6.0. Serial port programming in Visual Basic. Serial port programming in LabVIEW. Serial port programming in MATLAB. Serial port programming in Smalltalk. Serial port programming in Java.

  11. Serial Cognition and Personality in Macaques

    OpenAIRE

    Altschul, Drew M.; Herbert S Terrace; Alexander Weiss

    2016-01-01

    We examined the associations between serial cognition and personality in rhesus macaques (Macaca mulatta). Nine macaques were tested on a simultaneous chaining task to assess their cognitive abilities. They were also rated for personality traits and scored according to a previously extracted six component structure derived from free-ranging rhesus macaques. Friendliness and Openness were positively associated with good performance on three measures of accuracy on the serial learning task: Pro...

  12. The Skills Enhancement Training Program. Performance Report.

    Science.gov (United States)

    Food and Beverage Workers Union, Local 32, Washington, DC.

    This report describes a joint labor-management workplace literacy program called SET (Skills Enhancement Training) that targeted the more than 2,000 unionized employees of food service contractors at U.S. government institutions in Washington, D.C. Nineteen classes were offered and a total of 191 people self-selected themselves into the program.…

  13. Effects of early life stress and adolescent ethanol exposure on adult cognitive performance in the 5-choice serial reaction time task in Wistar male rats.

    Science.gov (United States)

    Boutros, Nathalie; Der-Avakian, Andre; Markou, Athina; Semenova, Svetlana

    2017-05-01

    Early life stress combined with heavy adolescent alcohol use predicts impaired neuropsychological functioning in adulthood. We investigated whether adolescent intermittent ethanol (AIE) exposure combined with neonatal maternal separation in rats altered attentional processes and impulsivity in adulthood. Male Wistar rat pups were exposed to maternal separation (postnatal days (PNDs) 1-14) and moderate AIE exposure (PNDs 28-57). Adult rats were tested in the five-choice serial reaction time task, which provides separate measures of attention, motor impulsivity, and compulsivity. Rats were tested under baseline conditions and in response to task manipulations that increased attentional load and impulsive behaviors, and after acute ethanol administration. Short stimulus and short intertrial interval (ITI) durations disrupted attention while long ITI durations impaired impulsivity in all rats. Moderate- and high-dose ethanol challenges impaired attention in all rats. Rats exposed to maternal separation and/or AIE exposure had significantly decreased omissions than non-handled water-exposed rats at baseline and tended to retain this effect in response to task challenges (i.e., the shorter stimulus and ITI durations, longer test session) and ethanol challenges, indicating moderate improvement of attentional performance. Maternal separation significantly increased perseverative responses at baseline and in response to decreased stimulus duration challenge, suggesting increased compulsivity. Separate or combined exposure to early life stress and AIE exposure moderately disrupts some aspects of adult executive control functions (e.g., increased compulsivity) but improves others (e.g., increased attention). The relative intensity of either manipulation during neonatal and adolescent periods may influence the direction in which cognitive behaviors are affected in adulthood.

  14. The nicotine metabolite, cotinine, attenuates glutamate (NMDA) antagonist-related effects on the performance of the five choice serial reaction time task (5C-SRTT) in rats.

    Science.gov (United States)

    Terry, Alvin V; Buccafusco, Jerry J; Schade, R Foster; Vandenhuerk, Leah; Callahan, Patrick M; Beck, Wayne D; Hutchings, Elizabeth J; Chapman, James M; Li, Pei; Bartlett, Michael G

    2012-04-01

    Cotinine, the most predominant metabolite of nicotine in mammalian species, has a pharmacological half-life that greatly exceeds its precursor. However, until recently, relatively few studies had been conducted to systematically characterize the behavioral pharmacology of cotinine. Our previous work indicated that cotinine improves prepulse inhibition of the auditory startle response in rats in pharmacological impairment models and that it improves working memory in non-human primates. Here we tested the hypothesis that cotinine improves sustained attention in rats and attenuates behavioral alterations induced by the glutamate (NMDA) antagonist MK-801. The effects of acute subcutaneous (dose range 0.03-10.0 mg/kg) and chronic oral administration (2.0 mg/kg/day in drinking water) of cotinine were evaluated in fixed and variable stimulus duration (VSD) as well as variable intertrial interval (VITI) versions of a five choice serial reaction time task (5C-SRTT). The results indicated only subtle effects of acute cotinine (administered alone) on performance of the 5C-SRTT (e.g., decreases in timeout responses). However, depending on dose, acute treatment with cotinine attenuated MK-801-related impairments in accuracy and elevations in timeout responses, and it increased the number of completed trials. Moreover, chronic cotinine attenuated MK-801-related impairments in accuracy and it reduced premature and timeout responses when the demands of the task were increased (i.e., by presenting VSDs or VITIs in addition to administering MK-801). These data suggest that cotinine may represent a prototype for compounds that have therapeutic potential for neuropsychiatric disorders (i.e., by improving sustained attention and decreasing impulsive and compulsive behaviors), especially those characterized by glutamate receptor alterations. Copyright © 2012 Elsevier Inc. All rights reserved.

  15. Cognitive Performance Enhancement Induced by Caffeine, Carbohydrate and Guarana Mouth Rinsing during Submaximal Exercise

    Directory of Open Access Journals (Sweden)

    Laura Pomportes

    2017-06-01

    Full Text Available The aim of this study was to investigate the influence of serial mouth rinsing (MR with nutritional supplements on cognitive performance (i.e., cognitive control and time perception during a 40-min submaximal exercise. Twenty-four participants completed 4 counterbalanced experimental sessions, during which they performed MR with either placebo (PL, carbohydrate (CHO: 1.6 g/25 mL, guarana complex (GUAc: 0.4 g/25 mL or caffeine (CAF: 67 mg/25 mL before and twice during exercise. The present study provided some important new insights regarding the specific changes in cognitive performance induced by nutritional supplements. The main results were: (1 CHO, CAF and GUA MR likely led participants to improve temporal performance; (2 CAF MR likely improved cognitive control; and (3 CHO MR led to a likely decrease in subjective perception of effort at the end of the exercise compared to PL, GUA and CAF. Moreover, results have shown that performing 40-min submaximal exercise enhances information processing in terms of both speed and accuracy, improves temporal performance and does not alter cognitive control. The present study opens up new perspectives regarding the use of MR to optimize cognitive performance during physical exercise.

  16. Gene doping: a review of performance-enhancing genetics.

    Science.gov (United States)

    Gaffney, Gary R; Parisotto, Robin

    2007-08-01

    Unethical athletes and their mentors have long arrogated scientific and medical advances to enhance athletic performance, thus gaining a dishonest competitive advantage. Building on advances in genetics, a new threat arises from athletes using gene therapy techniques in the same manner that some abused performance-enhancing drugs were used. Gene doping, as this is known, may produce spectacular physiologic alterations to dramatically enhance athletic abilities or physical appearance. Furthermore, gene doping may present pernicious problems for the regulatory agencies and investigatory laboratories that are entrusted to keep sporting events fair and ethical. Performance-enhanced genetics will likewise present unique challenges to physicians in many spheres of their practice.

  17. Performance Enhancement of Carbon Nanomaterials for Supercapacitors

    Directory of Open Access Journals (Sweden)

    Amin M. Saleem

    2016-01-01

    Full Text Available Carbon nanomaterials such as carbon nanotubes, carbon nanofibers, and graphene are exploited extensively due to their unique electrical, mechanical, and thermal properties and recently investigated for energy storage application (supercapacitor due to additional high specific surface area and chemical inertness properties. The supercapacitor is an energy storage device which, in addition to long cycle life (one million, can give energy density higher than parallel plate capacitor and power density higher than battery. In this paper, carbon nanomaterials and their composites are reviewed for prospective use as electrodes for supercapacitor. Moreover, different physical and chemical treatments on these nanomaterials which can potentially enhance the capacitance are also reviewed.

  18. Enhancing Astronaut Performance using Sensorimotor Adaptability Training

    Directory of Open Access Journals (Sweden)

    Jacob J Bloomberg

    2015-09-01

    Full Text Available Astronauts experience disturbances in balance and gait function when they return to Earth. The highly plastic human brain enables individuals to modify their behavior to match the prevailing environment. Subjects participating in specially designed variable sensory challenge training programs can enhance their ability to rapidly adapt to novel sensory situations. This is useful in our application because we aim to train astronauts to rapidly formulate effective strategies to cope with the balance and locomotor challenges associated with new gravitational environments - enhancing their ability to learn to learn. We do this by coupling various combinations of sensorimotor challenges with treadmill walking. A unique training system has been developed that is comprised of a treadmill mounted on a motion base to produce movement of the support surface during walking. This system provides challenges to gait stability. Additional sensory variation and challenge are imposed with a virtual visual scene that presents subjects with various combinations of discordant visual information during treadmill walking. This experience allows them to practice resolving challenging and conflicting novel sensory information to improve their ability to adapt rapidly. Information obtained from this work will inform the design of the next generation of sensorimotor countermeasures for astronauts.

  19. MODERN FACTORS THAT ENHANCE COMPANY'S FINANCIAL PERFORMANCE

    Directory of Open Access Journals (Sweden)

    Gruian Claudiu-Marian

    2011-12-01

    Full Text Available Company performance varies among economic sectors, countries and regions. It is influenced by a very large number of factors. This study aims at identifying and analyzing the determinants that must be considered by company's management presently in order to face competition and achieve superior financial performance. The research methodology used is specific for the theoretic nature of the article and includes literature review, comparative analysis and synthesis. Results validate and argue as relevant modern factors that influence the performance of contemporary companies: organizational culture, corporate social responsibility, innovation, knowledge spillovers. Study limits refer to the fact that these four factors are not entirely responsible for modern business performance and future research should be done to develop an integrative point of view on overall performance determinants. This paper is a dissemination of the results obtained by the author in the doctoral program The financial performance of EU member states companies, coordinator: Professor Carmen Corduneanu, PhD, carried out within West University of Timisoara, Romania, in the period October 2010- July 2012.

  20. Selection and Serial Entrepreneurs

    DEFF Research Database (Denmark)

    Chen, Jing

    2011-01-01

    Although it has been broadly evidenced that entrepreneurial experience plays a substantial role in the emergence of serial entrepreneurship, the debate is still going on about whether this relationship should be attributed to learning by doing or instead be explained by selection on ability. This...

  1. Suicide in serial killers.

    Science.gov (United States)

    Lester, David; White, John

    2010-02-01

    In a sample of 248 killers of two victims in America from 1900 to 2005, obtained from an encyclopedia of serial killers by Newton (2006), those completing suicide did not differ in sex, race, or the motive for the killing from those who were arrested.

  2. The Serial Perplex.

    Science.gov (United States)

    Blackwell, Maree Macon; Chopra, Pearl

    The problems associated with the acquisition of periodicals from various sources and different systems used by two University of Alabama libraries for the acquisition, controlling, and recording of serials are described in this report. Sources identified and discussed include local sources and suppliers, direct subscriptions placed with…

  3. Action Video Game Playing Is Reflected In Enhanced Visuomotor Performance and Increased Corticospinal Excitability.

    Science.gov (United States)

    Morin-Moncet, Olivier; Therrien-Blanchet, Jean-Marc; Ferland, Marie C; Théoret, Hugo; West, Greg L

    2016-01-01

    Action video game playing is associated with improved visuomotor performance; however, the underlying neural mechanisms associated with this increased performance are not well understood. Using the Serial Reaction Time Task in conjunction with Transcranial Magnetic Stimulation, we investigated if improved visuomotor performance displayed in action video game players (actionVGPs) was associated with increased corticospinal plasticity in primary motor cortex (M1) compared to non-video game players (nonVGPs). Further, we assessed if actionVGPs and nonVGPs displayed differences in procedural motor learning as measured by the SRTT. We found that at the behavioral level, both the actionVGPs and nonVGPs showed evidence of procedural learning with no significant difference between groups. However, the actionVGPs displayed higher visuomotor performance as evidenced by faster reaction times in the SRTT. This observed enhancement in visuomotor performance amongst actionVGPs was associated with increased corticospinal plasticity in M1, as measured by corticospinal excitability changes pre- and post- SRTT and corticospinal excitability at rest before motor practice. Our results show that aVGPs, who are known to have better performance on visual and motor tasks, also display increased corticospinal excitability after completing a novel visuomotor task.

  4. Action Video Game Playing Is Reflected In Enhanced Visuomotor Performance and Increased Corticospinal Excitability.

    Directory of Open Access Journals (Sweden)

    Olivier Morin-Moncet

    Full Text Available Action video game playing is associated with improved visuomotor performance; however, the underlying neural mechanisms associated with this increased performance are not well understood. Using the Serial Reaction Time Task in conjunction with Transcranial Magnetic Stimulation, we investigated if improved visuomotor performance displayed in action video game players (actionVGPs was associated with increased corticospinal plasticity in primary motor cortex (M1 compared to non-video game players (nonVGPs. Further, we assessed if actionVGPs and nonVGPs displayed differences in procedural motor learning as measured by the SRTT. We found that at the behavioral level, both the actionVGPs and nonVGPs showed evidence of procedural learning with no significant difference between groups. However, the actionVGPs displayed higher visuomotor performance as evidenced by faster reaction times in the SRTT. This observed enhancement in visuomotor performance amongst actionVGPs was associated with increased corticospinal plasticity in M1, as measured by corticospinal excitability changes pre- and post- SRTT and corticospinal excitability at rest before motor practice. Our results show that aVGPs, who are known to have better performance on visual and motor tasks, also display increased corticospinal excitability after completing a novel visuomotor task.

  5. TCP Performance Enhancement for UMTS Access Network

    DEFF Research Database (Denmark)

    Hu, Liang

    2008-01-01

    is between UMTS access network and Internet. The split proxy divides the bandwidth delay product into two parts, resulting in two TCP connections with smaller bandwidth delay products. Simulation results show, the split TCP proxy can significantly improve the TCP performance under high bit rate DCH channel......We aim at optimize the TCP performance over UMTS access network challenged by the large delay bandwidth product that is mainly caused by the latency from the link layer ARQ retransmissions and diversity technique at physical layer. We propose to place a split TCP proxy at GGSN nodes which...

  6. Enhanced Performance & Functionality of Tunable Delay Lines

    Science.gov (United States)

    2012-08-01

    Power penalty with respect to B2B of each channel for 2-, 4-, 8-fold multicasting. (c) Pulsewidth as a function of DGD along with eye diagrams of 2...performance curves for the back-to-back ( B2B ), minimum, middle, and maximum delay values. (b) 50, 40, 10 Gbs RZ-DPSK performance curves for B2B , minimum...9 10 80-Gb/s DQPSK ( B2B ) 80-Gb/s DQPSK (Max Delay) 80-Gb/s DQPSK (20ns) -L og 10 (B ER ) Received Power (dBm) -45 -40 -35 -30 -25 -20 2 3 4 5 6 7 8 9

  7. Using Mental Imagery to Enhance Athletic Performance.

    Science.gov (United States)

    Kenitzer, Raymond F.; Briddell, W. Bryan

    1991-01-01

    Four steps help coaches implement a mental imagery program to improve their athletes' performance and emotional control: evaluate athletes' imaging ability; provide an imaging warm-up; integrate the senses; and use goal achievement strategies. The article notes that imagery skills must be maintained and practiced consistently. (SM)

  8. managing reward strategy to enhance employee performance ...

    African Journals Online (AJOL)

    Prof

    compensate employees or risk their being poached by their competitors. .... taking, creativity; and. ▫ non-performance considerations. Customary or contractual, where the type of job, nature of the work, equity, tenure, level in hierarchy, and so .... to adopt better and more efficient methods and thereby increase production.

  9. Enhanced Cluster Computing Performance Through Proportional Fairness

    OpenAIRE

    Bonald, Thomas; Roberts, James

    2014-01-01

    International audience; The performance of cluster computing depends on how concurrent jobs share multiple data center resource types like CPU, RAM and disk storage. Recent research has discussed efficiency and fairness requirements and identified a number of desirable scheduling objectives including so-called dominant resource fairness (DRF). We argue here that proportional fairness (PF), long recognized as a desirable objective in sharing network bandwidth between ongoing flows, is preferab...

  10. Modelling swimming hydrodynamics to enhance performance

    OpenAIRE

    D.A. Marinho; Rouboa, A.; Barbosa, Tiago M.; Silva, A.J.

    2010-01-01

    Swimming assessment is one of the most complex but outstanding and fascinating topics in biomechanics. Computational fluid dynamics (CFD) methodology is one of the different methods that have been applied in swimming research to observe and understand water movements around the human body and its application to improve swimming performance. CFD has been applied attempting to understand deeply the biomechanical basis of swimming. Several studies have been conducted willing to analy...

  11. Strengthened enforcement enhances marine sanctuary performance

    Directory of Open Access Journals (Sweden)

    Brendan P. Kelaher

    2015-01-01

    Full Text Available Marine sanctuaries are areas where the extraction of biota is not permitted. Although most marine sanctuaries have a positive influence on biotic communities, not all sanctuaries are meeting their conservation objectives. Amidst possible explanations (e.g., size, age and isolation, insufficient enforcement is often speculated to be a key driver of marine sanctuary underperformance. Despite this, there are few studies directly linking quantitative enforcement data to changes in biotic communities within marine sanctuaries. Here, we used an asymmetrical-BACI experimental design from 2006–2012 to test whether new enforcement initiatives enhanced abundances of target fishes and threatened species in an existing large sub-tropical marine sanctuary relative to areas open to fishing. Implementation of the new enforcement initiatives in 2010 was associated with a 201% increase in annual fine rate and a significant increase in target fish and elasmobranch abundance, as well as sightings of a critically-endangered shark, in the marine sanctuary relative to areas open to fishing. Overall, these results demonstrate that strengthening enforcement can have a rapid positive influence on target fish and perhaps threatened species in a subtropical marine sanctuary. From this, we contend that increased enforcement guided by risk-based compliance planning and operations may be a useful first step for improving underperforming marine sanctuaries.

  12. Performance Enhancement using SQL Statement Tuning Approach

    Directory of Open Access Journals (Sweden)

    Hitesh Kumar SHARMA

    2017-07-01

    Full Text Available Tuning your SQL statements may be one of the most important tasks you can do to improve the performance of your Oracle system. By tuning your SQL statements to be as efficient as possible, you use your system to its full potential. Some of the things you can do to improve the efficiency of your SQL statements may involve as little effort as rewriting the SQL to take advantage of some property of your database or perhaps even changing the structure of the database itself.

  13. Lithographic Performance Enhancement Using Dummy Diffraction Mask

    Science.gov (United States)

    Yoo, Hyung Joun; Oh, Yong-Ho; Park, Byung-Sun; Choi, Sang Soo; Jeon, Young Jin; Lee, Choochon; Park, Sin-Chong

    1993-12-01

    The basic lithographic characteristics of the dummy diffraction mask which has two (dummy and main) mask layers, are investigated by simulation and experiment. The basic principle and theoretical details of the dummy diffraction mask are explained. Influences on the aerial image by the gap size and misorientation between two mask layers and by the nonideal phase grating, are simulated. Also, results of the lithographic performances for the simple patterns (line/space, isolated line, isolated space) and the complex patterns (V-shape active pattern in dynamic random access memory core cell) are presented.

  14. Surface engineering for enhanced performance against wear

    CERN Document Server

    2013-01-01

    Surface Engineering constitutes a variety of processes and sub processes. Each chapter of this work covers specific processes by experts working in the area. Included for each topic are tribological performances for each process as well as results of recent research. The reader also will benefit from in-depth studies of diffusion coatings, nanocomposite films for wear resistance, surfaces for biotribological applications, thin-film wear, tribology of thermal sprayed coatings, hardfacing, plating for tribology and high energy beam surface modifications. Material scientists as well as engineers working with surface engineering for tribology will be particularly interested in this work.

  15. Metaconcrete: Engineered aggregates for enhanced dynamic performance

    Science.gov (United States)

    Mitchell, Stephanie J.

    This work presents the development and investigation of a new type of concrete for the attenuation of waves induced by dynamic excitation. Recent progress in the field of metamaterials science has led to a range of novel composites which display unusual properties when interacting with electromagnetic, acoustic, and elastic waves. A new structural metamaterial with enhanced properties for dynamic loading applications is presented, which is named metaconcrete. In this new composite material the standard stone and gravel aggregates of regular concrete are replaced with spherical engineered inclusions. Each metaconcrete aggregate has a layered structure, consisting of a heavy core and a thin compliant outer coating. This structure allows for resonance at or near the eigenfrequencies of the inclusions, and the aggregates can be tuned so that resonant oscillations will be activated by particular frequencies of an applied dynamic loading. The activation of resonance within the aggregates causes the overall system to exhibit negative effective mass, which leads to attenuation of the applied wave motion. To investigate the behavior of metaconcrete slabs under a variety of different loading conditions a finite element slab model containing a periodic array of aggregates is utilized. The frequency dependent nature of metaconcrete is investigated by considering the transmission of wave energy through a slab, which indicates the presence of large attenuation bands near the resonant frequencies of the aggregates. Applying a blast wave loading to both an elastic slab and a slab model that incorporates the fracture characteristics of the mortar matrix reveals that a significant portion of the supplied energy can be absorbed by aggregates which are activated by the chosen blast wave profile. The transfer of energy from the mortar matrix to the metaconcrete aggregates leads to a significant reduction in the maximum longitudinal stress, greatly improving the ability of the material

  16. Enhanced performance large volume dissolution-DNP

    DEFF Research Database (Denmark)

    Bowen, Sean; Ardenkjær-Larsen, Jan Henrik

    2014-01-01

    A systematic study of the performance of the dissolution process in dissolution-DNP is presented. A relatively simple set of modifications is made to the standard Hypersense dissolution system to enable polarization of large volume samples. These consist of a large volume sample cup along...... with supporting modifications to the dissolution head and related components. Additional modifications were made to support the mapping of the temperature/pressure space of the dissolution process as well as enabling the use of large volumes of solvent and improving the robustness of the system. No loss...... of polarization was observed as sample size was increased to the 1g capacity of the large volume cup and for a dilution factor as low as 1:10....

  17. A phenomenological force model of Li-ion battery packs for enhanced performance and health management

    Science.gov (United States)

    Oh, Ki-Yong; Epureanu, Bogdan I.

    2017-10-01

    A 1-D phenomenological force model of a Li-ion battery pack is proposed to enhance the control performance of Li-ion battery cells in pack conditions for efficient performance and health management. The force model accounts for multiple swelling sources under the operational environment of electric vehicles to predict swelling-induced forces in pack conditions, i.e. mechanically constrained. The proposed force model not only incorporates structural nonlinearities due to Li-ion intercalation swelling, but also separates the overall range of states of charge into three ranges to account for phase transitions. Moreover, an approach to study cell-to-cell variations in pack conditions is proposed with serial and parallel combinations of linear and nonlinear stiffness, which account for battery cells and other components in the battery pack. The model is shown not only to accurately estimate the reaction force caused by swelling as a function of the state of charge, battery temperature and environmental temperature, but also to account for cell-to-cell variations due to temperature variations, SOC differences, and local degradation in a wide range of operational conditions of electric vehicles. Considering that the force model of Li-ion battery packs can account for many possible situations in actual operation, the proposed approach and model offer potential utility for the enhancement of current battery management systems and power management strategies.

  18. Pseudocapacitance effects for enhancement of capacitor performance

    Energy Technology Data Exchange (ETDEWEB)

    Lota, G.; Frackowiak, E. [Poznan University of Technology, Institute of Chemistry and Technical Electrochemistry, 60-965 Poznan, Piotrowo 3 (Poland)

    2010-10-15

    We report on the pseudo-capacitance induced by a nitrogen substituted in the carbon network composite prepared by a simple carbonisation (750 C) of formaldehyde and melamine in the presence of carbon nanotubes. Nitrogen content in the composites varied from 7.4 to 21.7 wt.%. Such materials have a higher density than activated carbons, hence, they can supply better volumetric capacity. N-rich composites show an excellent charge propagation at current loads from 500 mA g{sup -1} to 50 A g{sup -1} because of multiwalled nanotubes which play a conducting as well as a supporting role. The electrochemical performance of various composites was investigated in two- and three-electrode cells using acidic (1 mol L{sup -1} H{sub 2}SO{sub 4}), alkaline (6 mol L{sup -1}KOH), neutral (1 mol L{sup -1} Na{sub 2}SO{sub 4}) and organic electrolytes (1 mol L{sup -1} TEABF{sub 4} in acetonitrile). Organic and neutral medium is not adapted for N-rich carbon electrodes of supercapacitor. The detailed electrochemical characterisation pointed out the differences of charge propagation of electrodes with the different polarity. (Abstract Copyright [2010], Wiley Periodicals, Inc.)

  19. Enhancing the performance of Graphene NEMS

    Science.gov (United States)

    Parmar, Marsha

    In recent past Nanoelectromechanical systems (NEMS) have got several sensing based applications such as force, spin, charge and mass sensors. These devices due to their smaller size, operate in very high frequency regime (MHz - GHz) and have very high quality factors (102 -105) . Nevertheless these devices are limited by their comparatively smaller linear operational range. Electromechanical devices based on 2D materials are extremely sensitive to strain. We studied the effect of strain on the performance of single layer Graphene NEMS. Our results reveal that the strain in Graphene NEMS can be tuned to increase the linear operational range. We report a 25 dB increase in dynamic range by tuning the strain from 10-3at room temperature to 10-2 at 200K. This increase in dynamic range is also accompanied by partial cancellation of elastic and electrostatic nonlinearities. The resulting mass resolution estimated from the experimental data is 100 yg...................1 which is one order of magnitude better than previously reported values. Department of Science and technology, India. 2. CSIR, India.

  20. Delaware's first serial killer.

    Science.gov (United States)

    Inguito, G B; Sekula-Perlman, A; Lynch, M J; Callery, R T

    2000-11-01

    The violent murder of Shirley Ellis on November 29, 1987, marked the beginning of the strange and terrible tale of Steven Bryan Pennell's reign as the state of Delaware's first convicted serial killer. Three more bodies followed the first victim, and all had been brutally beaten and sadistically tortured. The body of a fifth woman has never been found. State and county police collaborated with the FBI to identify and hunt down their suspect, forming a task force of over 100 officers and spending about one million dollars. Through their knowledge and experience with other serial killers, the FBI was able to make an amazingly accurate psychological profile of Delaware's serial killer. After months of around-the-clock surveillance, Steven Pennell was arrested on November 29, 1988, one year to the day after the first victim was found. Pennell was found guilty in the deaths of the first two victims on November 29, 1989, and plead no contest to the murder of two others on October 30, 1991. Still maintaining his innocence, he asked for the death penalty so that he could spare his family further agony. Steven Pennell was executed by lethal injection on March 15, 1992.

  1. Enhanced thermoelectric performance of rough silicon nanowires

    Science.gov (United States)

    Hochbaum, Allon I.; Chen, Renkun; Delgado, Raul Diaz; Liang, Wenjie; Garnett, Erik C.; Najarian, Mark; Majumdar, Arun; Yang, Peidong

    2008-01-01

    Approximately 90 per cent of the world's power is generated by heat engines that use fossil fuel combustion as a heat source and typically operate at 30-40 per cent efficiency, such that roughly 15terawatts of heat is lost to the environment. Thermoelectric modules could potentially convert part of this low-grade waste heat to electricity. Their efficiency depends on the thermoelectric figure of merit ZT of their material components, which is a function of the Seebeck coefficient, electrical resistivity, thermal conductivity and absolute temperature. Over the past five decades it has been challenging to increase ZT>1, since the parameters of ZT are generally interdependent. While nanostructured thermoelectric materials can increase ZT>1 (refs 2-4), the materials (Bi, Te, Pb, Sb, and Ag) and processes used are not often easy to scale to practically useful dimensions. Here we report the electrochemical synthesis of large-area, wafer-scale arrays of rough Si nanowires that are 20-300nm in diameter. These nanowires have Seebeck coefficient and electrical resistivity values that are the same as doped bulk Si, but those with diameters of about 50nm exhibit 100-fold reduction in thermal conductivity, yielding ZT = 0.6 at room temperature. For such nanowires, the lattice contribution to thermal conductivity approaches the amorphous limit for Si, which cannot be explained by current theories. Although bulk Si is a poor thermoelectric material, by greatly reducing thermal conductivity without much affecting the Seebeck coefficient and electrical resistivity, Si nanowire arrays show promise as high-performance, scalable thermoelectric materials.

  2. D-cycloserine enhances spatial learning performances of rats ...

    African Journals Online (AJOL)

    D-cycloserine enhances spatial learning performances of rats chronically exposed to lead during the developmental period. ... the probe test and the visual cue test. In conclusion, DCS enhancement of the NMDA receptor function is an effective strategy to ameliorate neurotoxicity leadassociated spatial learning deficits.

  3. Enhancement of the Performance of a Transfer Field Electric ...

    African Journals Online (AJOL)

    Enhancement of the Performance of a Transfer Field Electric Machine Operating in the Asynchronous Mode. ... With the enhanced output power achievable by capacitance injection, the transfer field machine can compare favorably with an equivalent induction motor except that the synchronous speed is inherently limited to ...

  4. The use of genes for performance enhancement: doping or therapy?

    National Research Council Canada - National Science Library

    Oliveira, R S; Collares, T F; Smith, K R; Collares, T V; Seixas, F K

    2011-01-01

    ...) to enhance athletic performance. In such 'gene doping', exogenous genetic sequences are inserted into a specific tissue, altering cellular gene activity or leading to the expression of a protein product...

  5. Serial position learning in honeybees.

    Directory of Open Access Journals (Sweden)

    Randolf Menzel

    Full Text Available Learning of stimulus sequences is considered as a characteristic feature of episodic memory since it contains not only a particular item but also the experience of preceding and following events. In sensorimotor tasks resembling navigational performance, the serial order of objects is intimately connected with spatial order. Mammals and birds develop episodic(-like memory in serial spatio-temporal tasks, and the honeybee learns spatio-temporal order when navigating between the nest and a food source. Here I examine the structure of the bees' memory for a combined spatio-temporal task. I ask whether discrimination and generalization are based solely on simple forms of stimulus-reward learning or whether they require sequential configurations. Animals were trained to fly either left or right in a continuous T-maze. The correct choice was signaled by the sequence of colors (blue, yellow at four positions in the access arm. If only one of the possible 4 signals is shown (either blue or yellow, the rank order of position salience is 1, 2 and 3 (numbered from T-junction. No learning is found if the signal appears at position 4. If two signals are shown, differences at positions 1 and 2 are learned best, those at position 3 at a low level, and those at position 4 not at all. If three or more signals are shown these results are corroborated. This salience rank order again appeared in transfer tests, but additional configural phenomena emerged. Most of the results can be explained with a simple model based on the assumption that the four positions are equipped with different salience scores and that these add up independently. However, deviations from the model are interpreted by assuming stimulus configuration of sequential patterns. It is concluded that, under the conditions chosen, bees rely most strongly on memories developed during simple forms of associative reward learning, but memories of configural serial patterns contribute, too.

  6. The Performance Enhancement Group Program: Integrating Sport Psychology and Rehabilitation

    OpenAIRE

    Granito, Vincent J.; Hogan, Jeffery B.; Varnum, Lisa K.

    1995-01-01

    In an effort to improve the psychological health of the athlete who has sustained an injury, the Performance Enhancement Group program for injured athletes was created. This paper will offer a model for the Performance Enhancement Group program as a way to: 1) support the athlete, both mentally and physically; 2) deal with the demands of rehabilitation; and 3) facilitate the adjustments the athlete has to make while being out of the competitive arena. The program consists of responsibilities ...

  7. Active control for performance enhancement of electrically controlled rotor

    Directory of Open Access Journals (Sweden)

    Lu Yang

    2015-10-01

    Full Text Available Electrically controlled rotor (ECR system has the potential to enhance the rotor performance by applying higher harmonic flap inputs. In order to explore the feasibility and effectiveness for ECR performance enhancement using closed-loop control method, firstly, an ECR rotor performance analysis model based on helicopter flight dynamic model is established, which can reflect the performance characteristics of ECR helicopter at high advance ratio. Based on the simulation platform, an active control method named adaptive T-matrix algorithm is adopted to explore the feasibility and effectiveness for ECR performance enhancement. The simulation results verify the effectiveness of this closed-loop control method. For the sample ECR helicopter, about 3% rotor power reduction is obtained with the optimum 2/rev flap inputs at the advance ratio of 0.34. And through analyzing the distributions of attack of angle and drag in rotor disk, the underlying physical essence of ECR power reduction is cleared. Furthermore, the influence of the key control parameters, including convergence factor and weighting matrix, on the effectiveness of closed-loop control for ECR performance enhancement is explored. Some useful results are summarized, which can be used to direct the future active control law design of ECR performance enhancement.

  8. Machine performance assessment and enhancement for a hexapod machine

    Energy Technology Data Exchange (ETDEWEB)

    Mou, J.I. [Arizona State Univ., Tempe, AZ (United States); King, C. [Sandia National Labs., Livermore, CA (United States). Integrated Manufacturing Systems Center

    1998-03-19

    The focus of this study is to develop a sensor fused process modeling and control methodology to model, assess, and then enhance the performance of a hexapod machine for precision product realization. Deterministic modeling technique was used to derive models for machine performance assessment and enhancement. Sensor fusion methodology was adopted to identify the parameters of the derived models. Empirical models and computational algorithms were also derived and implemented to model, assess, and then enhance the machine performance. The developed sensor fusion algorithms can be implemented on a PC-based open architecture controller to receive information from various sensors, assess the status of the process, determine the proper action, and deliver the command to actuators for task execution. This will enhance a hexapod machine`s capability to produce workpieces within the imposed dimensional tolerances.

  9. Temporal Image Comparison (Serial Imaging) in Assessing Pigmented Lesions.

    Science.gov (United States)

    Drugge, Rhett J; Drugge, Elizabeth D

    2017-10-01

    The large-scale deployment of low-cost, noninvasive mechanisms of early detection are needed to reduce the melanoma burden. A serial 2-step system could power mass screening efforts serving the uninsured and underinsured as well as the rural and remote US counties where melanoma mortality is doubled for lack of access to dermatologists. Furthermore, serial melanoma screening strategies, serial total body photography and serial digital dermatoscopy imaging may be performed as a telehealth service, and thus would be available in any location that can support activity compliant with the Health Insurance Portability and Accountability Act and has appropriate bandwidth. Copyright © 2017 Elsevier Inc. All rights reserved.

  10. IMPLEMENTATION OF SERIAL AND PARALLEL BUBBLE SORT ON FPGA

    Directory of Open Access Journals (Sweden)

    Dwi Marhaendro Jati Purnomo

    2016-06-01

    Full Text Available Sorting is common process in computational world. Its utilization are on many fields from research to industry. There are many sorting algorithm in nowadays. One of the simplest yet powerful is bubble sort. In this study, bubble sort is implemented on FPGA. The implementation was taken on serial and parallel approach. Serial and parallel bubble sort then compared by means of its memory, execution time, and utility which comprises slices and LUTs. The experiments show that serial bubble sort required smaller memory as well as utility compared to parallel bubble sort. Meanwhile, parallel bubble sort performed faster than serial bubble sort

  11. Serial practice impairs motor skill consolidation.

    Science.gov (United States)

    Neville, Kristin-Marie; Trempe, Maxime

    2017-09-01

    Recent reports have revealed that motor skill learning is impaired if two skills are practiced one after the other, that is before the first skill has had the time to become consolidated. This suggests that motor skills should be practiced in isolation from one another to minimize interference. At the moment, little is known about the effect of practice schedules high in contextual interference on motor skill consolidation. In Experiment 1, we investigated whether a serial practice schedule impairs motor skill consolidation. Participants had to learn two distinct sequences of finger movements (A and B) under either a blocked practice schedule or a serial practice schedule before being retested the following day. A control group also practiced Sequence A only. Our results revealed that a blocked practice schedule led to no interference between the sequences, whereas a serial practice schedule impaired the consolidation of Sequence B. In Experiment 2, we investigated the origin of the interference caused by a serial practice schedule by replacing the physical practice of Sequence A with either the observation of a model performing Sequence A or by asking participants to produce random finger movements. Our results revealed that both tasks interfered with the consolidation of Sequence B. Thus, we suggest that a serial practice schedule impairs motor skill consolidation through a conflict in the brain networks involved in the acquisition of the cognitive representation of the sequence and its execution.

  12. Type 5 adenylyl cyclase disruption leads to enhanced exercise performance

    NARCIS (Netherlands)

    Vatner, Dorothy E.; Yan, Lin; Lai, Lo; Yuan, Chujun; Mouchiroud, Laurent; Pachon, Ronald E.; Zhang, Jie; Dillinger, Jean-Guillaume; Houtkooper, Riekelt H.; Auwerx, Johan; Vatner, Stephen F.

    2015-01-01

    The most important physiological mechanism mediating enhanced exercise performance is increased sympathetic, beta adrenergic receptor (beta-AR), and adenylyl cyclase (AC) activity. This is the first report of decreased AC activity mediating increased exercise performance. We demonstrated that AC5

  13. Can the Reporting of Local Government Performance enhance ...

    African Journals Online (AJOL)

    Statutorily, local government institutions in South Africa are expected to report their performance to central government on a regular basis. This paper argues that using this reporting information to also inform citizens and stakeholders about the performance of municipalities would enhance citizens' participation and improve ...

  14. Drink Availability is Associated with Enhanced Examination Performance in Adults

    Science.gov (United States)

    Pawson, Chris; Gardner, Mark R.; Doherty, Sarah; Martin, Laura; Soares, Rute; Edmonds, Caroline J.

    2013-01-01

    While dehydration has negative effects on memory and attention, few studies have investigated whether drinking water can enhance cognitive performance, and none have addressed this in a real-world setting. In this study we explored the potential benefits of the availability of water for undergraduates. The exam performance of students who brought…

  15. Serial Position Effects in Nonword Repetition

    Science.gov (United States)

    Gupta, P.; Lipinski, J.; Abbs, B.; Lin, P.H.

    2005-01-01

    A growing body of research has emphasized the linkage between performance in immediate serial recall of lists, nonword repetition, and word learning. Recently, it has been reported that primacy and recency effects are obtained in repetition of individual syllables within nonwords (Gupta, in press). Five experiments examined whether such…

  16. Recalling visual serial order for verbal sequences

    NARCIS (Netherlands)

    Logie, R.H.; Saito, S.; Morita, A.; Varma, S.; Norris, D.

    2016-01-01

    We report three experiments in which participants performed written serial recall of visually presented verbal sequences with items varying in visual similarity. In Experiments 1 and 2 native speakers of Japanese recalled visually presented Japanese Kanji characters. In Experiment 3, native speakers

  17. The New Generation of Performance Enhancement: The Use and Regulation of Cognitive Enhancers

    OpenAIRE

    Wolpin, Joseph

    2009-01-01

    Over the past decade, the use of steroids and other performance enhancing drugs has shaken the sports world. As athletes search for new and creative ways to gain advantages in their disciplines, nearly every major professional U.S. sports league as well as the National Collegiate Athletic Association (NCAA) and the United States Olympic Committee (USOC) has struggled to develop and enforce new rules against performance enhancing drugs. Much of the public attention and regulatory reaction has ...

  18. Psychologically-Informed Methods of Enhancing Endurance Performance

    OpenAIRE

    McCormick, Alister

    2016-01-01

    The main focus of this thesis was to determine psychologically-informed methods of enhancing endurance performance, particularly in endurance sport events. There were three main research aims. First, this thesis aimed to synthesise research conducted to date on the psychological determinants of endurance performance. A systematic literature review was conducted to identify psychological interventions that affect endurance performance in experimental research. Learning psychological skills, ve...

  19. The Effect of Concurrent Semantic Categorization on Delayed Serial Recall

    Science.gov (United States)

    Acheson, Daniel J.; MacDonald, Maryellen C.; Postle, Bradley R.

    2011-01-01

    The influence of semantic processing on the serial ordering of items in short-term memory was explored using a novel dual-task paradigm. Participants engaged in 2 picture-judgment tasks while simultaneously performing delayed serial recall. List material varied in the presence of phonological overlap (Experiments 1 and 2) and in semantic content…

  20. The role of item-specific information for the serial position curve in free recall.

    Science.gov (United States)

    Seiler, Kerstin H; Engelkamp, Johannes

    2003-09-01

    The serial position curve in free recall of a list of action phrases differs depending on whether the phrases were memorized by listening/reading (verbal task; VT) or by additionally enacting the denoted actions (subject-performed task; SPT). In VTs there is a clear primacy effect and a short recency effect. In SPTs there is no primacy effect but an extended recency effect. H. D. Zimmer, T. Helstrup, and J. Engelkamp (2000) assumed that SPTs provide excellent item-specific information, which leads to an automatic pop-out of the items presented last. In the present study, the authors assumed that good item-specific encoding generally enhances the recency effect and that it hinders rehearsal processes and thereby reduces the primacy effect. This assumption was confirmed. An item-specific orienting task leads to parallel serial position curves in VTs and SPTs with no primacy effect but a clear recency effect. Moreover, the same serial position effects were shown with nouns as learning material. An item-specific orienting task changes the classical U-shaped serial position curve with verbal material and leads to the disappearance of the primacy and the enhancement of the recency effect. (c) 2003 APA, all rights reserved

  1. Optimizing stochastic gradient descent algorithms for serially addressed adaptive-optics wavefront modulators.

    Science.gov (United States)

    Simpkins, Travis; Hui, Jeremy; Warde, Cardinal

    2007-10-20

    High-resolution adaptive-optical systems with thousands to millions of pixels will most likely have to employ serial- or matrix-addressed spatial light modulators (e.g., microelectromechanical-system-on-VLSI spatial light modulators). We compare parallel gradient descent adaptive-optics algorithms with serial gradient descent algorithms running on serially addressed modulators. While serial algorithms have previously been shown to require more iterations than parallel algorithms, we show that, because of the limitations of the databus, each serial iteration of the algorithm on a serial modulator requires significantly less time to complete than a parallel iteration, thereby favoring the serial algorithm when time to convergence is used as the performance metric. Thus, such high-resolution serially addressed devices are generally better matched to the serial-update wavefront correction algorithm owing to the data load penalty imposed by the bandwidth-limited databus of these modulators.

  2. EEG correlates of enhanced spatial performance following exposure to music.

    Science.gov (United States)

    Rideout, B E; Laubach, C M

    1996-04-01

    Previous research has shown that exposure to classical music can influence performance on a spatial task. The present study investigated EEG correlates of this enhanced performance effect, 4 female and 4 male undergraduates completed two equivalent spatial tests, one following a control procedure and one following the presentation of Mozart's Sonata for Two Pianos in D Major. EEG was recorded during a baseline and two task-performance periods. Test performance and EEG recordings were analyzed, and correlations were generated between task performance and EEG variables (average spectral power and peak frequency within 5 frequency ranges). Performance improved significantly following the presentation of the music. EEG analysis indicated 6 reliable correlations out of 40 calculated between differential EEG variables and changes in performance. Ten reliable correlations out of 120 were also found between changes in performance and nondifferential EEG variables across baseline, control, and experimental conditions.

  3. Action Video Game Playing Is Reflected In Enhanced Visuomotor Performance and Increased Corticospinal Excitability

    OpenAIRE

    Morin-Moncet, Olivier; Therrien-Blanchet, Jean-Marc; Ferland, Marie C.; Th?oret, Hugo; West, Greg L.

    2016-01-01

    Action video game playing is associated with improved visuomotor performance; however, the underlying neural mechanisms associated with this increased performance are not well understood. Using the Serial Reaction Time Task in conjunction with Transcranial Magnetic Stimulation, we investigated if improved visuomotor performance displayed in action video game players (actionVGPs) was associated with increased corticospinal plasticity in primary motor cortex (M1) compared to non-video game play...

  4. Nonlinear Process Fault Diagnosis Based on Serial Principal Component Analysis.

    Science.gov (United States)

    Deng, Xiaogang; Tian, Xuemin; Chen, Sheng; Harris, Chris J

    2016-12-22

    Many industrial processes contain both linear and nonlinear parts, and kernel principal component analysis (KPCA), widely used in nonlinear process monitoring, may not offer the most effective means for dealing with these nonlinear processes. This paper proposes a new hybrid linear-nonlinear statistical modeling approach for nonlinear process monitoring by closely integrating linear principal component analysis (PCA) and nonlinear KPCA using a serial model structure, which we refer to as serial PCA (SPCA). Specifically, PCA is first applied to extract PCs as linear features, and to decompose the data into the PC subspace and residual subspace (RS). Then, KPCA is performed in the RS to extract the nonlinear PCs as nonlinear features. Two monitoring statistics are constructed for fault detection, based on both the linear and nonlinear features extracted by the proposed SPCA. To effectively perform fault identification after a fault is detected, an SPCA similarity factor method is built for fault recognition, which fuses both the linear and nonlinear features. Unlike PCA and KPCA, the proposed method takes into account both linear and nonlinear PCs simultaneously, and therefore, it can better exploit the underlying process's structure to enhance fault diagnosis performance. Two case studies involving a simulated nonlinear process and the benchmark Tennessee Eastman process demonstrate that the proposed SPCA approach is more effective than the existing state-of-the-art approach based on KPCA alone, in terms of nonlinear process fault detection and identification.

  5. Enhancing team-sport athlete performance: is altitude training relevant?

    Science.gov (United States)

    Billaut, François; Gore, Christopher J; Aughey, Robert J

    2012-09-01

    Field-based team sport matches are composed of short, high-intensity efforts, interspersed with intervals of rest or submaximal exercise, repeated over a period of 60-120 minutes. Matches may also be played at moderate altitude where the lower oxygen partial pressure exerts a detrimental effect on performance. To enhance run-based performance, team-sport athletes use varied training strategies focusing on different aspects of team-sport physiology, including aerobic, sprint, repeated-sprint and resistance training. Interestingly, 'altitude' training (i.e. living and/or training in O(2)-reduced environments) has only been empirically employed by athletes and coaches to improve the basic characteristics of speed and endurance necessary to excel in team sports. Hypoxia, as an additional stimulus to training, is typically used by endurance athletes to enhance performance at sea level and to prepare for competition at altitude. Several approaches have evolved in the last few decades, which are known to enhance aerobic power and, thus, endurance performance. Altitude training can also promote an increased anaerobic fitness, and may enhance sprint capacity. Therefore, altitude training may confer potentially-beneficial adaptations to team-sport athletes, which have been overlooked in contemporary sport physiology research. Here, we review the current knowledge on the established benefits of altitude training on physiological systems relevant to team-sport performance, and conclude that current evidence supports implementation of altitude training modalities to enhance match physical performances at both sea level and altitude. We hope that this will guide the practice of many athletes and stimulate future research to better refine training programmes.

  6. [Banned performance enhancing ergogenic aids in children and adolescent athletes].

    Science.gov (United States)

    Nemet, Dan; Eliakim, Alon

    2007-10-01

    Ergogenic aids (from the Greek, ergon, meaning work) are ingested to enhance energy utilization in athletes. In recent years there has been an increase in youth participating in competitive sports and, as a consequence, a concomitant increase in the usage of performance enhancing substances. Ergogenic aid usage could influence, or its efficiency could be influenced, during this period of rapid growth and sexual maturation, and by the marked hormonal fluctuations. Ephedra alkaloids; pain relief medications, diuretics, anabolic steroids and protein hormones are among the ergogenic aids used by young athletes. While there is no scientific evidence to support the usage of these agents for enhancing performance in children and adolescents, using supra-physiological doses may be associated with undesired side effects.

  7. Evaluation of GPS/BDS indoor positioning performance and enhancement

    Science.gov (United States)

    He, Zhe; Petovello, Mark; Pei, Ling; Olesen, Daniel M.

    2017-02-01

    This paper assesses the potential of using BDS and GPS signals to position in challenged environments such as indoors. Traditional assisted GNSS approaches that use code phase as measurements (i.e., coarse-time solutions) are shown to be prone to multipath and noise. An enhanced approach that has superior sensitivity and positioning performance-the so-called direct positioning receiver architecture-has been implemented and evaluated using live indoor BDS and/or GPS signals. Real indoor experiments have been conducted in Shanghai and significant improvement has been observed with enhanced approaches: results with BDS constellation show better horizontal positioning performance (biases are less than 10 m) than using GPS alone, but are slightly worse in the vertical axis; when using the enhanced approach with BDS and GPS, both horizontal and vertical axes show promising results for the environments considered herein; the coarse-time state converges faster and is more reliable compared to other solutions.

  8. Tin (Sn) for enhancing performance in silicon CMOS

    KAUST Repository

    Hussain, Aftab M.

    2013-10-01

    We study a group IV element: tin (Sn) by integrating it into silicon lattice, to enhance the performance of silicon CMOS. We have evaluated the electrical properties of the SiSn lattice by performing simulations using First-principle studies, followed by experimental device fabrication and characterization. We fabricated high-κ/metal gate based Metal-Oxide-Semiconductor capacitors (MOSCAPs) using SiSn as channel material to study the impact of Sn integration into silicon. © 2013 IEEE.

  9. Sleep Deprivation Impairs and Caffeine Enhances My Performance, but Not Always Our Performance.

    Science.gov (United States)

    Faber, Nadira S; Häusser, Jan A; Kerr, Norbert L

    2017-02-01

    What effects do factors that impair or enhance performance in individuals have when these individuals act in groups? We provide a framework, called the GIE ("Effects of Grouping on Impairments and Enhancements") framework, for investigating this question. As prominent examples for individual-level impairments and enhancements, we discuss sleep deprivation and caffeine. Based on previous research, we derive hypotheses on how they influence performance in groups, specifically process gains and losses in motivation, individual capability, and coordination. We conclude that the effect an impairment or enhancement has on individual-level performance is not necessarily mirrored in group performance: grouping can help or hurt. We provide recommendations on how to estimate empirically the effects individual-level performance impairments and enhancements have in groups. By comparing sleep deprivation to stress and caffeine to pharmacological cognitive enhancement, we illustrate that we cannot readily generalize from group results on one impairment or enhancement to another, even if they have similar effects on individual-level performance.

  10. Performance-Enhancing Drugs in Sports: How Chemists Catch Users

    Science.gov (United States)

    Werner, T. C.; Hatton, Caroline K.

    2011-01-01

    The "cat-and-mouse game" between those who enable athletes to use performance-enhancing drugs (PEDs) and those who try to detect such use provides a wealth of interesting examples for the undergraduate chemistry and biochemistry classroom. In this article, we focus on several commonly used PEDs, including amphetamine, anabolic steroids,…

  11. Does strategic planning enhance or impede innovation and firm performance

    NARCIS (Netherlands)

    Song, Michael; Im, Subin; van der Bijl, H.M.; Song, Lisa Z.

    2011-01-01

    Does strategic planning enhance or impede innovation and firm performance? The current literature provides contradictory views. This study extends the resource-advantage theory to examine the conditions in which strategic planning increases or decreases the number of new product development projects

  12. Does strategic planning enhance or impede innovation and firm performance?

    NARCIS (Netherlands)

    Song, Michael; Im, Subin; van der Bij, Hans; Song, Lisa Z.

    Does strategic planning enhance or impede innovation and firm performance? The current literature provides contradictory views. This study extends the resource-advantage theory to examine the conditions in which strategic planning increases or decreases the number of new product development projects

  13. Enhancing The Performance Of Cooperative Societies In Abia State ...

    African Journals Online (AJOL)

    Against the background of recent economic reforms in the rural development sector and the enhanced linkages between the extension agency and cooperative societies this paper compares the performance of three categories of cooperatives, namely, farming, trading and agro-industrial. A multi stage stratified sampling ...

  14. Enhancing Performance of Farmers' Cooperative in Rice Innovation ...

    African Journals Online (AJOL)

    The state has witnessed proliferation of farmers' cooperative; and while new ones are emerging in their numbers, some old ones are becoming less functional and others going into extinct The study examined factors for enhancing performance of rice farmers' cooperative in rice innovation system. Seventy members of rice ...

  15. Use of Martial Art Exercises in Performance Enhancement Training.

    Science.gov (United States)

    McClellan, Tim; Anderson, Warren

    2002-01-01

    Details some of the many martial arts training techniques and their potential applications for inclusion in performance enhancement programs, focusing on the benefits of martial training, the arts continuum, and martial arts training modes. The article concludes that the various martial arts techniques provide a stimulating and intuitively…

  16. Role of Disorder in Enhancing Lithium-Ion Battery Performance

    DEFF Research Database (Denmark)

    Yue, Yuanzheng; He, W.

    and type of disorder, material performances can be significantly enhanced. Disorder can be tuned by doping, calcination, redox reaction, composition tuning, and so on. Recently we have fabricated a cathode material for lithium ion battery by introducing heterostructure and disorder into the material...

  17. Staff training and development, enhancement of job performance ...

    African Journals Online (AJOL)

    The success of any organization/institution lies on the ability of its workforce to deliver. This ability/skill is acquired through training, which enhances job performance. In essence, the research examined the training and development programmes enjoyed by all senior staff of FUTO library with the aim of finding out its effects ...

  18. Priming of Spatial Distance Enhances Children's Creative Performance

    Science.gov (United States)

    Liberman, Nira; Polack, Orli; Hameiri, Boaz; Blumenfeld, Maayan

    2012-01-01

    According to construal level theory, psychological distance promotes more abstract thought. Theories of creativity, in turn, suggest that abstract thought promotes creativity. Based on these lines of theorizing, we predicted that spatial distancing would enhance creative performance in elementary school children. To test this prediction, we primed…

  19. Effects of various additives to enhance growth performance, blood ...

    African Journals Online (AJOL)

    Effects of various additives to enhance growth performance, blood profiles, and reduce malodour emissions in growing pigs. W.G. Kwak, I.H. Park, W Yun, J.H. Lee, C.H. Lee, S.Y. Oh, H.J. Oh, Shudong Liu, Y.H. Kim, J.C. Park, G.S. Kim, J.H. Cho ...

  20. Serial and spatial error correlation

    NARCIS (Netherlands)

    Elhorst, J. Paul

    This paper demonstrates that jointly modeling serial and spatial error correlation results in a trade-off between the serial and spatial autocorrelation coefficients. Ignoring this trade-off causes inefficiency and may lead to nonstationarity. (C) 2008 Elsevier B.V. All rights reserved.

  1. Hyperbaric Oxygen Environment Can Enhance Brain Activity and Multitasking Performance.

    Science.gov (United States)

    Vadas, Dor; Kalichman, Leonid; Hadanny, Amir; Efrati, Shai

    2017-01-01

    Background: The Brain uses 20% of the total oxygen supply consumed by the entire body. Even though, multitasking), the oxygen supply is shifted from one brain region to another, via blood perfusion modulation. The aim of the present study was to evaluate whether a hyperbaric oxygen (HBO) environment, with increased oxygen supply to the brain, will enhance the performance of complex and/or multiple activities. Methods: A prospective, double-blind randomized control, crossover trial including 22 healthy volunteers. Participants were asked to perform a cognitive task, a motor task and a simultaneous cognitive-motor task (multitasking). Participants were randomized to perform the tasks in two environments: (a) normobaric air (1 ATA 21% oxygen) (b) HBO (2 ATA 100% oxygen). Two weeks later participants were crossed to the alternative environment. Blinding of the normobaric environment was achieved in the same chamber with masks on while hyperbaric sensation was simulated by increasing pressure in the first minute and gradually decreasing to normobaric environment prior to tasks performance. Results: Compared to the performance at normobaric conditions, both cognitive and motor single tasks scores were significantly enhanced by HBO environment (p Multitasking performance was also significantly enhanced in HBO environment (p = 0.006 for the cognitive part and p = 0.02 for the motor part). Conclusions: The improvement in performance of both single and multi-tasking while in an HBO environment supports the hypothesis which according to, oxygen is indeed a rate limiting factor for brain activity. Hyperbaric oxygenation can serve as an environment for brain performance. Further studies are needed to evaluate the optimal oxygen levels for maximal brain performance.

  2. Stiffness of serial and quasi-serial manipulators: comparison analysis

    Directory of Open Access Journals (Sweden)

    Klimchik Alexandr

    2016-01-01

    Full Text Available The paper deals with comparison analysis of serial and quasi-serial manipulators. It shows a difference between stiffness behaviours of corresponding industrial robots under external loading, which is caused by machining process. The analysis is based on the estimation of compliance errors induced by cutting forces that are applied to the manipulator end-effector. We demonstrate that the quasi-seral manipulators are preferable for large-dimensional tasks while the quasi-serial ones better suit small size tasks.

  3. Recalling visual serial order for verbal sequences.

    Science.gov (United States)

    Logie, Robert H; Saito, Satoru; Morita, Aiko; Varma, Samarth; Norris, Dennis

    2016-05-01

    We report three experiments in which participants performed written serial recall of visually presented verbal sequences with items varying in visual similarity. In Experiments 1 and 2 native speakers of Japanese recalled visually presented Japanese Kanji characters. In Experiment 3, native speakers of English recalled visually presented words. In all experiments, items varied in visual similarity and were controlled for phonological similarity. For Kanji and for English, performance on lists comprising visually similar items was overall poorer than for lists of visually distinct items across all serial positions. For mixed lists in which visually similar and visually distinct items alternated through the list, a clear "zig-zag" pattern appeared with better recall of the visually distinct items than for visually similar items. This is the first time that this zig-zag pattern has been shown for manipulations of visual similarity in serial-ordered recall. These data provide new evidence that retaining a sequence of visual codes relies on similar principles to those that govern the retention of a sequence of phonological codes. We further illustrate this by demonstrating that the data patterns can be readily simulated by at least one computational model of serial-ordered recall, the Primacy model (Page and Norris, Psychological Review, 105(4), 761-81, 1998). Together with previous evidence from neuropsychological studies and experimental studies with healthy adults, these results are interpreted as consistent with two domain-specific, limited-capacity, temporary memory systems for phonological material and for visual material, respectively, each of which uses similar processes that have evolved to be optimal for retention of serial order.

  4. Dynamics of serial position change in probe-recognition task

    Directory of Open Access Journals (Sweden)

    Fifić Mario

    2002-01-01

    Full Text Available Relationship between practice and serial position effects was investigated, in order to obtain more evidence for underlying short-term memory processes. The investigated relationship is termed the dynamics of serial position change. To address this issue, the present study investigated mean latency, errors, and performed Ex-Gaussian convolution analysis. In six-block trials the probe-recognition task was used in the so-called fast experimental procedure. The serial position effect was significant in all six blocks. Both primacy and recency effects were detected, with primacy located in the first two blocks, producing a non-linear serial position effect. Although the serial position function became linear from the third block on, the convolution analysis revealed a non-linear change of the normal distribution parameter, suggesting special status of the last two serial positions. Further, separation of convolution parameters for serial position and practice was observed, suggesting different underlying mechanisms. In order to account for these findings, a strategy shift mechanism is suggested, rather then a mechanism based on changing the manner of memory scanning. Its influence is primarily located at the very beginning of the experimental session. The pattern of results of errors regarding the dynamics of serial position change closely paralleled those on reaction times. Several models of short-term memory were evaluated in order to account for these findings.

  5. Enhancing imagery through hypnosis: a performance aid for athletes.

    Science.gov (United States)

    Liggett, D R

    2000-10-01

    This value of imagery in sports is widely acknowledged. The contribution of hypnosis to enhancing athletes' performance is also recognized, but the value of hypnosis in enhancing imagery has little recognition. The reason for this neglect is explored. The study used Martens' Sport Imagery Questionnaire, which asked the participants to image 4 different situations in their own sport--practicing alone, practicing in front of others, watching a teammate, and competing. Participants reported their subjective impression of vividness on four dimensions--visual, auditory, kinesthetic, and affective. The 14 athletes participating imaged each situation in and out of hypnosis--half of the time the imagery in hypnosis came first and half after. The participants reported that the imagery under hypnosis was more intense for each dimension and more intense for each situation. Whether the imagery was done under hypnosis first or after was not significant. The findings suggest that hypnosis substantially enhances imagery intensity and effectiveness.

  6. Evaluation of GPS/BDS indoor positioning performance and enhancement

    DEFF Research Database (Denmark)

    He, Zhe; Petovello, Mark; Pei, Ling

    2017-01-01

    This paper assesses the potential of using BDS and GPS signals to position in challenged environments such as indoors. Traditional assisted GNSS approaches that use code phase as measurements (i.e., coarse-time solutions) are shown to be prone to multipath and noise. An enhanced approach that has...... superior sensitivity and positioning performance—the so-called direct positioning receiver architecture—has been implemented and evaluated using live indoor BDS and/or GPS signals. Real indoor experiments have been conducted in Shanghai and significant improvement has been observed with enhanced approaches......: results with BDS constellation show better horizontal positioning performance (biases are less than 10m) than using GPS alone, but are slightly worse in the vertical axis; when using the enhanced approach with BDS and GPS, both horizontal and vertical axes show promising results for the environments...

  7. Composite Materials for Thermal Energy Storage: Enhancing Performance through Microstructures

    Science.gov (United States)

    Ge, Zhiwei; Ye, Feng; Ding, Yulong

    2014-01-01

    Chemical incompatibility and low thermal conductivity issues of molten-salt-based thermal energy storage materials can be addressed by using microstructured composites. Using a eutectic mixture of lithium and sodium carbonates as molten salt, magnesium oxide as supporting material, and graphite as thermal conductivity enhancer, the microstructural development, chemical compatibility, thermal stability, thermal conductivity, and thermal energy storage performance of composite materials are investigated. The ceramic supporting material is essential for preventing salt leakage and hence provides a solution to the chemical incompatibility issue. The use of graphite gives a significant enhancement on the thermal conductivity of the composite. Analyses suggest that the experimentally observed microstructural development of the composite is associated with the wettability of the salt on the ceramic substrate and that on the thermal conduction enhancer. PMID:24591286

  8. Automated Voxel-Based Analysis of Volumetric Dynamic Contrast-Enhanced CT Data Improves Measurement of Serial Changes in Tumor Vascular Biomarkers

    Energy Technology Data Exchange (ETDEWEB)

    Coolens, Catherine, E-mail: catherine.coolens@rmp.uhn.on.ca [Radiation Medicine Program, Princess Margaret Cancer Center and University Health Network, Toronto, Ontario (Canada); Department of Radiation Oncology, University of Toronto, Toronto, Ontario (Canada); Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, Ontario (Canada); Driscoll, Brandon [Radiation Medicine Program, Princess Margaret Cancer Center and University Health Network, Toronto, Ontario (Canada); Chung, Caroline [Radiation Medicine Program, Princess Margaret Cancer Center and University Health Network, Toronto, Ontario (Canada); Department of Radiation Oncology, University of Toronto, Toronto, Ontario (Canada); Shek, Tina; Gorjizadeh, Alborz [Radiation Medicine Program, Princess Margaret Cancer Center and University Health Network, Toronto, Ontario (Canada); Ménard, Cynthia [Radiation Medicine Program, Princess Margaret Cancer Center and University Health Network, Toronto, Ontario (Canada); Department of Radiation Oncology, University of Toronto, Toronto, Ontario (Canada); Jaffray, David [Radiation Medicine Program, Princess Margaret Cancer Center and University Health Network, Toronto, Ontario (Canada); Department of Radiation Oncology, University of Toronto, Toronto, Ontario (Canada); Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, Ontario (Canada)

    2015-01-01

    Objectives: Development of perfusion imaging as a biomarker requires more robust methodologies for quantification of tumor physiology that allow assessment of volumetric tumor heterogeneity over time. This study proposes a parametric method for automatically analyzing perfused tissue from volumetric dynamic contrast-enhanced (DCE) computed tomography (CT) scans and assesses whether this 4-dimensional (4D) DCE approach is more robust and accurate than conventional, region-of-interest (ROI)-based CT methods in quantifying tumor perfusion with preliminary evaluation in metastatic brain cancer. Methods and Materials: Functional parameter reproducibility and analysis of sensitivity to imaging resolution and arterial input function were evaluated in image sets acquired from a 320-slice CT with a controlled flow phantom and patients with brain metastases, whose treatments were planned for stereotactic radiation surgery and who consented to a research ethics board-approved prospective imaging biomarker study. A voxel-based temporal dynamic analysis (TDA) methodology was used at baseline, at day 7, and at day 20 after treatment. The ability to detect changes in kinetic parameter maps in clinical data sets was investigated for both 4D TDA and conventional 2D ROI-based analysis methods. Results: A total of 7 brain metastases in 3 patients were evaluated over the 3 time points. The 4D TDA method showed improved spatial efficacy and accuracy of perfusion parameters compared to ROI-based DCE analysis (P<.005), with a reproducibility error of less than 2% when tested with DCE phantom data. Clinically, changes in transfer constant from the blood plasma into the extracellular extravascular space (K{sub trans}) were seen when using TDA, with substantially smaller errors than the 2D method on both day 7 post radiation surgery (±13%; P<.05) and by day 20 (±12%; P<.04). Standard methods showed a decrease in K{sub trans} but with large uncertainty (111.6 ± 150.5) %. Conclusions

  9. Performance Enhancement of the Patch Antennas Applying Micromachining Technology

    Directory of Open Access Journals (Sweden)

    Mohamed N. Azermanesh

    2007-09-01

    Full Text Available This paper reports on the application of micromachining technology for performance enhancement of two types of compact antennas which are becoming a common practice in microsystems. Shorted patch antennas (SPA and folded shorted patch antennas operating in the 5-6 GHz ISM band, with intended application in short-range wireless communications, are considered. The electrical length of antennas are modified by etching the substrate of the antennas, thus providing a new degree of freedom to control the antenna operating properties, which is the main novelty of our work. The gain and bandwidth of the antennas are increased by increasing the etching depth. However, etching the substrate affects the operating frequency as well. To keep the operating frequency at a pre-specified value, the dimension of the antennas must be increased by deepening the etching depth. Therefore, a trade off between the performance enhancement of the antennas and the dimensional enlargement is required.

  10. Vent Control as a Means of Enhancing Airbag Performance

    Directory of Open Access Journals (Sweden)

    Richard E. Zimmermann

    2002-01-01

    Full Text Available Typical automotive airbag systems have a fixed area vent for exiting gasses. The US Army Cockpit Airbag System (CABS is unvented to prolong the period during which the system can provide occupant protection during extended helicopter crash scenarios. In each application, system performance may be enhanced by providing a controlled vent area. This paper describes work conducted under a Phase I SBIR program sponsored by the NASA Langley Research Center. The work was focused on eventual inflatable restraint system applications in general aviation aircraft, and showed that appropriate vent control offers many enhancements. Two series of tests conducted during Phase I showed that inflatable restraint system size and weight can be reduced without degrading performance, injury potential in an out of position situation (OOPS deployment can be reduced, and peak bag pressures can be reduced (at any temperature during normal operation.

  11. Mechanisms for training security inspectors to enhance human performance

    Energy Technology Data Exchange (ETDEWEB)

    Burkhalter, H.E.; Sessions, J.C.

    1988-01-01

    The Department of Energy (DOE) has established qualification standards for protective force personnel employed at nuclear facilities (10 CFR Part 1046 (Federal Register)). Training mechanisms used at Los Alamos to enhance human performance in meeting DOE standards include, but are not limited to, the following: for cardio-respiratory training, they utilize distance running, interval training, sprint training, pacing, indoor aerobics and circuit training; for muscular strength, free weights, weight machines, light hand weights, grip strength conditioners, and calistenics are employed; for muscular endurance, participants do high repetitions (15 - 40) using dumbbells, flex weights, resistive rubber bands, benches, and calisthenics; for flexibility, each training session devotes specific times to stretch the muscles involved for a particular activity. These training mechanisms with specific protocols can enhance human performance.

  12. Tablet computer enhanced training improves internal medicine exam performance

    OpenAIRE

    Baumgart, Daniel C.; Wende, Ilja; Grittner, Ulrike

    2017-01-01

    Background Traditional teaching concepts in medical education do not take full advantage of current information technology. We aimed to objectively determine the impact of Tablet PC enhanced training on learning experience and MKSAP? (medical knowledge self-assessment program) exam performance. Methods In this single center, prospective, controlled study final year medical students and medical residents doing an inpatient service rotation were alternatingly assigned to either the active test ...

  13. Assessment of mass detection performance in contrast enhanced digital mammography

    Science.gov (United States)

    Carton, Ann-Katherine; de Carvalho, Pablo M.; Li, Zhijin; Dromain, Clarisse; Muller, Serge

    2015-03-01

    We address the detectability of contrast-agent enhancing masses for contrast-agent enhanced spectral mammography (CESM), a dual-energy technique providing functional projection images of breast tissue perfusion and vascularity using simulated CESM images. First, the realism of simulated CESM images from anthropomorphic breast software phantoms generated with a software X-ray imaging platform was validated. Breast texture was characterized by power-law coefficients calculated in data sets of real clinical and simulated images. We also performed a 2-alternative forced choice (2-AFC) psychophysical experiment whereby simulated and real images were presented side-by-side to an experienced radiologist to test if real images could be distinguished from the simulated images. It was found that texture in our simulated CESM images has a fairly realistic appearance. Next, the relative performance of human readers and previously developed mathematical observers was assessed for the detection of iodine-enhancing mass lesions containing different contrast agent concentrations. A four alternative-forced-choice (4 AFC) task was designed; the task for the model and human observer was to detect which one of the four simulated DE recombined images contained an iodineenhancing mass. Our results showed that the NPW and NPWE models largely outperform human performance. After introduction of an internal noise component, both observers approached human performance. The CHO observer performs slightly worse than the average human observer. There is still work to be done in improving model observers as predictors of human-observer performance. Larger trials could also improve our test statistics. We hope that in the future, this framework of software breast phantoms, virtual image acquisition and processing, and mathematical observers can be beneficial to optimize CESM imaging techniques.

  14. Performance-enhancing sports supplements: role in critical care.

    Science.gov (United States)

    Weitzel, Lindsay-Rae B; Sandoval, Paul A; Mayles, W Jonathan; Wischmeyer, Paul E

    2009-10-01

    Many performance-enhancing supplements and/or drugs are increasing in popularity among professional and amateur athletes alike. Although the uncontrolled use of these agents can pose health risks in the general population, their clearly demonstrated benefits could prove helpful to the critically ill population in whom preservation and restoration of lean body mass and neuromuscular function are crucial. Post-intensive care unit weakness not only impairs post-intensive care unit quality of life but also correlates with intensive care unit mortality. This review covers a number of the agents known to enhance athletic performance, and their possible role in preservation of muscle function and prevention/treatment of post-intensive care unit weakness in critically ill patients. These agents include testosterone analogues, growth hormone, branched chain amino acid, glutamine, arginine, creatine, and beta-hydryoxy-beta-methylbutyrate. Three of the safest and most effective agents in enhancing athletic performance in this group are creatine, branched-chain amino acid, and beta-hydryoxy-beta-methylbutyrate. However, these agents have received very little study in the recovering critically ill patient suffering from post-intensive care unit weakness. More placebo-controlled studies are needed in this area to determine efficacy and optimal dosing. It is very possible that, under the supervision of a physician, many of these agents may prove beneficial in the prevention and treatment of post-intensive care unit weakness.

  15. Spinal Manipulative Therapy and Sports Performance Enhancement: A Systematic Review.

    Science.gov (United States)

    Botelho, Marcelo B; Alvarenga, Bruno A P; Molina, Nícolly; Ribas, Marcos; Baptista, Abrahão F

    2017-09-01

    The purpose of this study was to review the literature regarding the relationship between spinal manipulative therapy (SMT) and sports performance. PubMed and Embase databases were searched for original studies published up to July 2016. Inclusion criteria were if SMT has been applied to athletes and if any sports performance-related outcome was measured. Of the 581 potential studies, 7 clinical trials were selected. Most studies had adequate quality (≥6/11) when assessed by the PEDro scale. None of those studies assessed performance at an event or competition. Four studies revealed improvement in a sports performance test after SMT. Meta-analysis could not be performed because of the wide differences in methodologies, design, and outcomes measured. Spinal manipulative therapy influences a wide range of neurophysiological parameters that could be associated with sports performance. Of the 3 studies where SMT did not improve test performance, 2 used SMT not for therapeutic correction of a dysfunctional vertebral joint but to an arbitrary previously set joint. Although 4 of 7 studies showed that SMT improved sports performance tests, the evidence is still weak to support its use. Spinal manipulative therapy may be a promising approach for performance enhancement that should be investigated with more consistent methodologic designs. Copyright © 2017. Published by Elsevier Inc.

  16. Performance enhancement of OSPF protocol in the private network

    Science.gov (United States)

    Yang, Yang; Lu, Yang; Lin, Xiaokang

    2005-11-01

    The private network serves as an information exchange platform to support the integrated services via microwave channels and accordingly selects the open shortest path first (OSPF) as the IP routing protocol. But the existing OSPF can't fit the private network very well for its special characteristics. This paper presents our modifications to the standard protocol in such aspects as the single-area scheme, link state advertisement (LSA) types and formats, OSPF packet formats, important state machines, setting of protocol parameters and link flap damping. Finally simulations are performed in various scenarios and the results indicate that our modifications can enhance the OSPF performance in the private network effectively.

  17. Conditions for enhanced performance of segmented thermoelectrics under load

    Science.gov (United States)

    Angst, Sebastian; Wolf, Dietrich E.

    2017-08-01

    The Onsager-de Groot-Callen transport theory is used to investigate the performance of double segmented thermoelectrics as generators. We show that such an inhomogeneous device usually performs worse than predicted by the effective transport coefficients. This is caused by the difference of the open circuit Seebeck voltage and the Seebeck voltage under operating conditions. The electrical current and the related interface Peltier effect cause a self-organization of the temperature profile such that the temperature drop across the material with the higher absolute Seebeck coefficient is reduced. However, including Joule heating we derive conditions for the opposite effect resulting in an enhanced power.

  18. Progress in performance enhancement methods for capacitive silicon resonators

    Science.gov (United States)

    Van Toan, Nguyen; Ono, Takahito

    2017-11-01

    In this paper, we review the progress in recent studies on the performance enhancement methods for capacitive silicon resonators. We provide information on various fabrication technologies and design considerations that can be employed to improve the performance of capacitive silicon resonators, including low motional resistance, small insertion loss, and high quality factor (Q). This paper contains an overview of device structures and working principles, fabrication technologies consisting of hermetic packaging, deep reactive-ion etching and neutral beam etching, and design considerations including mechanically coupled, movable electrode structures and piezoresistive heat engines.

  19. Implementation of a Multichannel Serial Data Streaming Algorithm using the Xilinx Serial RapidIO Solution

    Science.gov (United States)

    Doxley, Charles A.

    2016-01-01

    In the current world of applications that use reconfigurable technology implemented on field programmable gate arrays (FPGAs), there is a need for flexible architectures that can grow as the systems evolve. A project has limited resources and a fixed set of requirements that development efforts are tasked to meet. Designers must develop robust solutions that practically meet the current customer demands and also have the ability to grow for future performance. This paper describes the development of a high speed serial data streaming algorithm that allows for transmission of multiple data channels over a single serial link. The technique has the ability to change to meet new applications developed for future design considerations. This approach uses the Xilinx Serial RapidIO LOGICORE Solution to implement a flexible infrastructure to meet the current project requirements with the ability to adapt future system designs.

  20. Enhancement on Wingate Anaerobic Test Performance With Hyperventilation.

    Science.gov (United States)

    Leithäuser, Renate M; Böning, Dieter; Hütler, Matthias; Beneke, Ralph

    2016-07-01

    Relatively long-lasting metabolic alkalizing procedures such as bicarbonate ingestion have potential for improving performance in long-sprint to middle-distance events. Within a few minutes, hyperventilation can induce respiratory alkalosis. However, corresponding performance effects are missing or equivocal at best. To test a potential performance-enhancing effect of respiratory alkalosis in a 30-s Wingate Anaerobic Test (WAnT). 10 men (mean ± SD age 26.6 ± 4.9 y, height 184.4 ± 6.1 cm, body-mass test 1 80.7 ± 7.7 kg, body-mass test 2 80.4 ± 7.2 kg, peak oxygen uptake 3.95 ± 0.43 L/min) performed 2 WAnTs, 1 with and 1 without a standardized 15-min hyperventilation program pre-WAnT in randomized order separated by 1 wk. Compared with the control condition, hyperventilation reduced (all P Hyperventilation-induced respiratory alkalosis can enhance WAnT cycling sprint performance well in the magnitude of what is seen after successful bicarbonate ingestion.

  1. Exploring the Implications of Emotional Intelligence to Enhance Employees’ Performance

    Directory of Open Access Journals (Sweden)

    Muhammad Bashir Khan

    2013-05-01

    Full Text Available Emotional intelligence (EI is an effective tool to increase organizational productivity. This study depicts the impact of EI on employees’ performance who are engaged with customer services by using four elements i.e. self awareness, self management, social awareness and relationship management. A sample of 120 respondents was selected from four paint manufacturing companies in Pakistan. The primary data was collected through the structured questionnaire and simple regression method was used to investigate the relationship between employee’s performance and emotional intelligence. The results illustrate that EI has positive impact on employee’s performance. It is suggested that the implication of EI be ensured as contemporary need of customer services in paint industries so that organization productivity may be enhanced with efficient employees’ performance.

  2. Predicting students' intention to use stimulants for academic performance enhancement.

    Science.gov (United States)

    Ponnet, Koen; Wouters, Edwin; Walrave, Michel; Heirman, Wannes; Van Hal, Guido

    2015-02-01

    The non-medical use of stimulants for academic performance enhancement is becoming a more common practice among college and university students. The objective of this study is to gain a better understanding of students' intention to use stimulant medication for the purpose of enhancing their academic performance. Based on an extended model of Ajzen's theory of planned behavior, we examined the predictive value of attitude, subjective norm, perceived behavioral control, psychological distress, procrastination, substance use, and alcohol use on students' intention to use stimulants to improve their academic performance. The sample consisted of 3,589 Flemish university and college students (mean age: 21.59, SD: 4.09), who participated anonymously in an online survey conducted in March and April 2013. Structural equation modeling was used to investigate the relationships among the study variables. Our results indicate that subjective norm is the strongest predictor of students' intention to use stimulant medication, followed by attitude and perceived behavioral control. To a lesser extent, procrastinating tendencies, psychological distress, and substance abuse contribute to students' intention. Conclusions/ Importance: Based on these findings, we provide several recommendations on how to curtail students' intention to use stimulant medication for the purpose of improving their academic performance. In addition, we urge researchers to identify other psychological variables that might be related to students' intention.

  3. Serial Input Output

    Energy Technology Data Exchange (ETDEWEB)

    Waite, Anthony; /SLAC

    2011-09-07

    Serial Input/Output (SIO) is designed to be a long term storage format of a sophistication somewhere between simple ASCII files and the techniques provided by inter alia Objectivity and Root. The former tend to be low density, information lossy (floating point numbers lose precision) and inflexible. The latter require abstract descriptions of the data with all that that implies in terms of extra complexity. The basic building blocks of SIO are streams, records and blocks. Streams provide the connections between the program and files. The user can define an arbitrary list of streams as required. A given stream must be opened for either reading or writing. SIO does not support read/write streams. If a stream is closed during the execution of a program, it can be reopened in either read or write mode to the same or a different file. Records represent a coherent grouping of data. Records consist of a collection of blocks (see next paragraph). The user can define a variety of records (headers, events, error logs, etc.) and request that any of them be written to any stream. When SIO reads a file, it first decodes the record name and if that record has been defined and unpacking has been requested for it, SIO proceeds to unpack the blocks. Blocks are user provided objects which do the real work of reading/writing the data. The user is responsible for writing the code for these blocks and for identifying these blocks to SIO at run time. To write a collection of blocks, the user must first connect them to a record. The record can then be written to a stream as described above. Note that the same block can be connected to many different records. When SIO reads a record, it scans through the blocks written and calls the corresponding block object (if it has been defined) to decode it. Undefined blocks are skipped. Each of these categories (streams, records and blocks) have some characteristics in common. Every stream, record and block has a name with the condition that each

  4. Current Perspectives on Profiling and Enhancing Wheelchair Court Sport Performance.

    Science.gov (United States)

    Paulson, Thomas; Goosey-Tolfrey, Victoria

    2017-03-01

    Despite the growing interest in Paralympic sport, the evidence base for supporting elite wheelchair sport performance remains in its infancy when compared with able-bodied (AB) sport. Subsequently, current practice is often based on theory adapted from AB guidelines, with a heavy reliance on anecdotal evidence and practitioner experience. Many principles in training prescription and performance monitoring with wheelchair athletes are directly transferable from AB practice, including the periodization and tapering of athlete loads around competition, yet considerations for the physiological consequences of an athlete's impairment and the interface between athlete and equipment are vital when targeting interventions to optimize in-competition performance. Researchers and practitioners are faced with the challenge of identifying and implementing reliable protocols that detect small but meaningful changes in impairment-specific physical capacities and on-court performance. Technologies to profile both linear and rotational on-court performance are an essential component of sport-science support to understand sport-specific movement profiles and prescribe training intensities. In addition, an individualized approach to the prescription of athlete training and optimization of the "wheelchair-user interface" is required, accounting for an athlete's anthropometrics, sports classification, and positional role on court. In addition to enhancing physical capacities, interventions must focus on the integration of the athlete and his or her equipment, as well as techniques for limiting environmental influence on performance. Taken together, the optimization of wheelchair sport performance requires a multidisciplinary approach based on the individual requirements of each athlete.

  5. Enhanced Component Performance Study. Emergency Diesel Generators 1998–2013

    Energy Technology Data Exchange (ETDEWEB)

    Schroeder, John Alton [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2014-11-01

    This report presents an enhanced performance evaluation of emergency diesel generators (EDGs) at U.S. commercial nuclear power plants. This report evaluates component performance over time using Institute of Nuclear Power Operations (INPO) Consolidated Events Database (ICES) data from 1998 through 2013 and maintenance unavailability (UA) performance data using Mitigating Systems Performance Index (MSPI) Basis Document data from 2002 through 2013. The objective is to present an analysis of factors that could influence the system and component trends in addition to annual performance trends of failure rates and probabilities. The factors analyzed for the EDG component are the differences in failures between all demands and actual unplanned engineered safety feature (ESF) demands, differences among manufacturers, and differences among EDG ratings. Statistical analyses of these differences are performed and results showing whether pooling is acceptable across these factors. In addition, engineering analyses were performed with respect to time period and failure mode. The factors analyzed are: sub-component, failure cause, detection method, recovery, manufacturer, and EDG rating.

  6. The serial message-passing schedule for LDPC decoding algorithms

    Science.gov (United States)

    Liu, Mingshan; Liu, Shanshan; Zhou, Yuan; Jiang, Xue

    2015-12-01

    The conventional message-passing schedule for LDPC decoding algorithms is the so-called flooding schedule. It has the disadvantage that the updated messages cannot be used until next iteration, thus reducing the convergence speed . In this case, the Layered Decoding algorithm (LBP) based on serial message-passing schedule is proposed. In this paper the decoding principle of LBP algorithm is briefly introduced, and then proposed its two improved algorithms, the grouped serial decoding algorithm (Grouped LBP) and the semi-serial decoding algorithm .They can improve LBP algorithm's decoding speed while maintaining a good decoding performance.

  7. Psychological skills for enhancing performance: arousal regulation strategies.

    Science.gov (United States)

    Gould, D; Udry, E

    1994-04-01

    This review summarizes and integrates current empirical and theoretical research on arousal regulation strategies for enhancing athletic performance. The need to view arousal as a multifaceted construct made up of both cognitive and physiological components was emphasized, as well as the importance of understanding arousal-performance relationship theories that go beyond a simple inverted-U notion. Categories of arousal regulation strategies were discussed and included: arousal energizing techniques, biofeedback techniques, relaxation response strategies, cognitive behavioral interventions, and mental preparation routines. It was concluded that these techniques can be effective in influencing arousal and facilitating performance. However, additional research (especially evaluation research) using more rigorous methods, determining how and why interventions work, using case study methodologies, identifying personality and situational factors influencing arousal regulation effectiveness, and identifying the most effective means of teaching arousal regulation is needed.

  8. Magnetic Particle Recovery of Serial Numbers

    Energy Technology Data Exchange (ETDEWEB)

    D. Utrata; M.J. Johnson

    2003-10-01

    One method used by crime labs to recover obliterated serial numbers in steel firearms (ferrous samples) is the magnetic particle technique. The use of this method is predicated on the detection of metal deformation present under stamped serial numbers after the visible stamp has been removed. Equipment specialized for this detection is not used in these attempts; a portable magnetic yoke used typically for flaw detection on large weldments or structures, along with dry visible magnetic powders, have been the tools of criminologists working in this area. Crime labs have reported low success rates using these tools [1, 2]. This is not surprising when one considers that little formal development has apparently evolved for use in such investigations since the publication of seminal work in this area some time ago [3]. The aim of this project is to investigate specific aspects of magnetic particle inspection for serial number recovery. This includes attempts to understand the magnetic characteristics of different steels that affect their performance in the test, such as varying results for carbon steels and alloy steels after different thermal and forming treatments. Also investigated are the effects of the nature of the sample magnetization (AC, rectified DC, and true DC) and the use of various detection media, such as visible powders and fluorescent sprays, on test outcome. Additionally, some aspects of surface preparation of firearm samples prior to number recovery were included in this work. The scope of this report includes a brief overview of the magnetic particle inspection method in general and its applications to forensic serial number recovery. This is followed by a description of how such investigations were simulated on lab samples, including a look at how the microstructure of a given steel will affect its performance in the test. Investigations into the serial number recovery in a series of ferromagnetic firearms (both steel and certain stainless steels

  9. Enhanced Microgrid Dynamic Performance Using a Modulated Power Filter Based on Enhanced Bacterial Foraging Optimization

    Directory of Open Access Journals (Sweden)

    Ahmed M. Othman

    2017-06-01

    Full Text Available This paper presents a design of microgrid (MG with enhanced dynamic performance. Distributed energy resources (DER are widely used in MGs to match the various load types and profiles. DERs include solar PV cells, wind energy sources, fuel cells, batteries, micro gas-engines and storage elements. MG will include AC/DC circuits, developed power electronics devices, inverters and power electronic controllers. A novel modulated power filters (MPF device will be applied in MG design. Enhanced bacterial foraging optimization (EBFO will be proposed to optimize and set the MPF parameters to enhance and tune the MG dynamic response. Recent dynamic control is applied to minimize the harmonic reference content. EBFO will adapt the gains of MPF dynamic control. The present research achieves an enhancement of MG dynamic performance, in addition to ensuring improvements in the power factor, bus voltage profile and power quality. MG operation will be evaluated by the dynamic response to be fine-tuned by MPF based on EBFO. Digital simulations have validated the results to show the effectiveness and efficient improvement by the proposed strategy.

  10. Performance limits of plasmon-enhanced organic photovoltaics

    Energy Technology Data Exchange (ETDEWEB)

    Karatay, Durmus U.; Ginger, David S., E-mail: ginger@chem.washington.edu [Department of Physics, University of Washington, Seattle, Washington 98195 (United States); Department of Chemistry, University of Washington, Seattle, Washington 98195 (United States); Salvador, Michael [Department of Chemistry, University of Washington, Seattle, Washington 98195 (United States); Yao, Kai [Department of Materials Science and Engineering, University of Washington, Seattle, Washington 98195 (United States); Jen, Alex K.-Y. [Department of Chemistry, University of Washington, Seattle, Washington 98195 (United States); Department of Materials Science and Engineering, University of Washington, Seattle, Washington 98195 (United States)

    2014-07-21

    We use a combination of experiment and modeling to explore the promise and limitations of using plasmon-resonant metal nanoparticles to enhance the device performance of organic photovoltaics (OPVs). We focus on optical properties typical of the current generation of low-bandgap donor polymers blended with the fullerene (6,6)-phenyl C{sub 71}-butyric acid methyl ester (PC{sub 71}BM) and use the polymer poly(indacenodithiophene-co-phenanthro[9,10-b]quinoxaline) (PIDT-PhanQ) as our test case. We model the optical properties and performance of these devices both in the presence and absence of a variety of colloidal silver nanoparticles. We show that for these materials, device performance is sensitive to the relative z-position and the density of nanoparticles inside the active layer. Using conservative estimates of the internal quantum efficiency for the PIDT-PhanQ/PC{sub 71}BM blend, we calculate that optimally placed silver nanoparticles could yield an enhancement in short-circuit current density of over 31% when used with ∼ 80-nm-thick active layers, resulting in an absolute increase in power conversion efficiency of up to ∼2% for the device based on optical engineering.

  11. Electrocortical Evidence of Enhanced Performance Monitoring in Social Anxiety.

    Science.gov (United States)

    Judah, Matt R; Grant, DeMond M; Frosio, Kristen E; White, Evan J; Taylor, Danielle L; Mills, Adam C

    2016-03-01

    Self-focused attention is thought to be a key feature of social anxiety disorder. Yet few studies have used event-related potentials (ERPs) to examine whether socially anxious individuals display greater monitoring of their performance and attention to their errors. Similarly, only a few studies have used ERPs to examine how social anxiety is related to processing of performance feedback. Individuals with high (n=26) and low (n=28) levels of social anxiety completed a trial-and-error learning task. Self-focus was manipulated using false heart-rate feedback during a random subset of trials. Performance feedback was given using emotional and neutral faces in a positive context (correct=happy face; incorrect=neutral face) and negative context (correct=neutral face; incorrect=disgust face) in order to investigate biased interpretation and attention to feedback. Socially anxious subjects displayed enhanced amplitude of the ERN and CRN, suggesting greater response monitoring, and enhanced Pe amplitude, suggesting greater processing of errors relative to the low social anxiety group. No group differences were observed with respect to feedback processing. Before learning stimulus-response mappings in the negative context, the FRN was larger for self-focus compared to standard trials and marginally larger for socially anxious subjects compared to controls. These findings support cognitive models and suggest avenues for future research. Copyright © 2016. Published by Elsevier Ltd.

  12. Engineering Nanostructural Routes for Enhancing Thermoelectric Performance: Bulk to Nanoscale.

    Science.gov (United States)

    Mohanraman, Rajeshkumar; Lan, Tian-Wey; Hsiung, Te-Chih; Amada, Dedi; Lee, Ping-Chung; Ou, Min-Nan; Chen, Yang-Yuan

    2015-01-01

    Thermoelectricity is a very important phenomenon, especially its significance in heat-electricity conversion. If thermoelectric devices can be effectively applied to the recovery of the renewable energies, such as waste heat and solar energy, the energy shortage, and global warming issues may be greatly relieved. This review focusses recent developments on the thermoelectric performance of a low-dimensional material, bulk nanostructured materials, conventional bulk materials etc. Particular emphasis is given on, how the nanostructure in nanostructured composites, confinement effects in one-dimensional nanowires and doping effects in conventional bulk composites plays an important role in ZT enhancement.

  13. The Enhancing Impact of Friendship Networks on Sales Managers’ Performance

    Directory of Open Access Journals (Sweden)

    Danny Pimentel Claro

    2013-04-01

    Full Text Available This paper examines how relationships with friends moderate the impact of professional networks on sales performance. Based on a sample of 204 sales managers in a professional service company, this study presents evidence that friendship networks amplify the effect of sales forces’ professional networks on new product sales as well as on prospecting and converting new deals. Our results offer important insights into the socio-cognitive perspective of sales management literature and suggest that firms should encourage managers to improve their friendships in order to access valuable information that will enhance customer knowledge and support their sales efforts.

  14. Enhanced Component Performance Study: Emergency Diesel Generators 1998–2014

    Energy Technology Data Exchange (ETDEWEB)

    Schroeder, John Alton [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2015-11-01

    This report presents an enhanced performance evaluation of emergency diesel generators (EDGs) at U.S. commercial nuclear power plants. This report evaluates component performance over time using (1) Institute of Nuclear Power Operations (INPO) Consolidated Events Database (ICES) data from 1998 through 2014 and (2) maintenance unavailability (UA) performance data from Mitigating Systems Performance Index (MSPI) Basis Document data from 2002 through 2014. The objective is to show estimates of current failure probabilities and rates related to EDGs, trend these data on an annual basis, determine if the current data are consistent with the probability distributions currently recommended for use in NRC probabilistic risk assessments, show how the reliability data differ for different EDG manufacturers and for EDGs with different ratings; and summarize the subcomponents, causes, detection methods, and recovery associated with each EDG failure mode. Engineering analyses were performed with respect to time period and failure mode without regard to the actual number of EDGs at each plant. The factors analyzed are: sub-component, failure cause, detection method, recovery, manufacturer, and EDG rating. Six trends with varying degrees of statistical significance were identified in the data.

  15. The effect of concurrent semantic categorization on delayed serial recall

    OpenAIRE

    Acheson, D.; Postle, B.; Macdonald, M

    2011-01-01

    The influence of semantic processing on the serial ordering of items in short-term memory was explored using a novel dual-task paradigm. Subjects engaged in two picture judgment tasks while simultaneously performing delayed serial recall. List material varied in the presence of phonological overlap (Experiments 1 and 2) and in semantic content (concrete words in Experiment 1 and 3; nonwords in Experiments 2 and 3). Picture judgments varied in the extent to which they required accessing visual...

  16. Image jitter enhances visual performance when spatial resolution is impaired.

    Science.gov (United States)

    Watson, Lynne M; Strang, Niall C; Scobie, Fraser; Love, Gordon D; Seidel, Dirk; Manahilov, Velitchko

    2012-09-06

    Visibility of low-spatial frequency stimuli improves when their contrast is modulated at 5 to 10 Hz compared with stationary stimuli. Therefore, temporal modulations of visual objects could enhance the performance of low vision patients who primarily perceive images of low-spatial frequency content. We investigated the effect of retinal-image jitter on word recognition speed and facial emotion recognition in subjects with central visual impairment. Word recognition speed and accuracy of facial emotion discrimination were measured in volunteers with AMD under stationary and jittering conditions. Computer-driven and optoelectronic approaches were used to induce retinal-image jitter with duration of 100 or 166 ms and amplitude within the range of 0.5 to 2.6° visual angle. Word recognition speed was also measured for participants with simulated (Bangerter filters) visual impairment. Text jittering markedly enhanced word recognition speed for people with severe visual loss (101 ± 25%), while for those with moderate visual impairment, this effect was weaker (19 ± 9%). The ability of low vision patients to discriminate the facial emotions of jittering images improved by a factor of 2. A prototype of optoelectronic jitter goggles produced similar improvement in facial emotion discrimination. Word recognition speed in participants with simulated visual impairment was enhanced for interjitter intervals over 100 ms and reduced for shorter intervals. Results suggest that retinal-image jitter with optimal frequency and amplitude is an effective strategy for enhancing visual information processing in the absence of spatial detail. These findings will enable the development of novel tools to improve the quality of life of low vision patients.

  17. Improving human object recognition performance using video enhancement techniques

    Science.gov (United States)

    Whitman, Lucy S.; Lewis, Colin; Oakley, John P.

    2004-12-01

    Atmospheric scattering causes significant degradation in the quality of video images, particularly when imaging over long distances. The principle problem is the reduction in contrast due to scattered light. It is known that when the scattering particles are not too large compared with the imaging wavelength (i.e. Mie scattering) then high spatial resolution information may be contained within a low-contrast image. Unfortunately this information is not easily perceived by a human observer, particularly when using a standard video monitor. A secondary problem is the difficulty of achieving a sharp focus since automatic focus techniques tend to fail in such conditions. Recently several commercial colour video processing systems have become available. These systems use various techniques to improve image quality in low contrast conditions whilst retaining colour content. These systems produce improvements in subjective image quality in some situations, particularly in conditions of haze and light fog. There is also some evidence that video enhancement leads to improved ATR performance when used as a pre-processing stage. Psychological literature indicates that low contrast levels generally lead to a reduction in the performance of human observers in carrying out simple visual tasks. The aim of this paper is to present the results of an empirical study on object recognition in adverse viewing conditions. The chosen visual task was vehicle number plate recognition at long ranges (500 m and beyond). Two different commercial video enhancement systems are evaluated using the same protocol. The results show an increase in effective range with some differences between the different enhancement systems.

  18. Mindfulness Enhances Episodic Memory Performance: Evidence from a Multimethod Investigation.

    Science.gov (United States)

    Brown, Kirk Warren; Goodman, Robert J; Ryan, Richard M; Anālayo, Bhikkhu

    2016-01-01

    Training in mindfulness, classically described as a receptive attentiveness to present events and experiences, has been shown to improve attention and working memory. Both are key to long-term memory formation, and the present three-study series used multiple methods to examine whether mindfulness would enhance episodic memory, a key form of long-term memory. In Study 1 (N = 143), a self-reported state of mindful attention predicted better recognition performance in the Remember-Know (R-K) paradigm. In Study 2 (N = 93), very brief training in a focused attention form of mindfulness also produced better recognition memory performance on the R-K task relative to a randomized, well-matched active control condition. Study 3 (N = 57) extended these findings by showing that relative to randomized active and inactive control conditions the effect of very brief mindfulness training generalized to free-recall memory performance. This study also found evidence for mediation of the mindfulness training-episodic memory relation by intrinsic motivation. These findings indicate that mindful attention can beneficially impact motivation and episodic memory, with potential implications for educational and occupational performance.

  19. Mindfulness Enhances Episodic Memory Performance: Evidence from a Multimethod Investigation.

    Directory of Open Access Journals (Sweden)

    Kirk Warren Brown

    Full Text Available Training in mindfulness, classically described as a receptive attentiveness to present events and experiences, has been shown to improve attention and working memory. Both are key to long-term memory formation, and the present three-study series used multiple methods to examine whether mindfulness would enhance episodic memory, a key form of long-term memory. In Study 1 (N = 143, a self-reported state of mindful attention predicted better recognition performance in the Remember-Know (R-K paradigm. In Study 2 (N = 93, very brief training in a focused attention form of mindfulness also produced better recognition memory performance on the R-K task relative to a randomized, well-matched active control condition. Study 3 (N = 57 extended these findings by showing that relative to randomized active and inactive control conditions the effect of very brief mindfulness training generalized to free-recall memory performance. This study also found evidence for mediation of the mindfulness training-episodic memory relation by intrinsic motivation. These findings indicate that mindful attention can beneficially impact motivation and episodic memory, with potential implications for educational and occupational performance.

  20. Processing solubility enhancement and Nanoparticles dispersion enhanced Performance Materials through thermomagnetic processing

    Energy Technology Data Exchange (ETDEWEB)

    Ludtka, Gerard Michael [ORNL; Ludtka, Gail Mackiewicz- [ORNL; Rios, Orlando [ORNL; Kisner, Roger A [ORNL; Muralidharan, Govindarajan [ORNL; Manuel, Michele Viola [University of Florida, Gainesville; Manuel, Michele [University of Florida, Gainesville

    2012-01-01

    This research demonstrates that significantly enhanced materials microstructures and improved performance can be achieved by coupling two previously independent materials research concepts, namely, the thermo-magnetic processing (T-MP)1 and the electromagnetic acoustic transducer (EMAT)2 technologies. In prior, separate NHMFL research endeavors, ORNL researchers have demonstrated that: (1) thermo-magnetic processing (T-MP) can significantly enhance Ni solubility in Fe by up to 30%; and (2) using the electromagnetic acoustic transducer (EMAT) technology can significantly improve cast product homogeneity. Based on these earlier successful results, we proposed simultaneously coupling these two R&D approaches/eff ects (i.e., T-MP with EMAT), in order to simultaneously achieve: (1) enhanced elemental solid-solubility in Mg and in at least one Fe-based alloy; and (2) uniform dispersion of intentional additions of inert nanoparticles in Mg. Developing homogeneous dispersions of inert nanoparticles is and has been pursued as one of the holy grails for achieving unprecedented materials performance and highly desired mechanical properties, e.g., in creep and oxidation resistant alloys. Successfully coupling these two technologies would provide the ability to create uniquely controlled nano-scale microstructures that currently are unachievable by any other materials processing technologies.

  1. Maximizing Drilling Performance through Enhanced Solid Control System

    Science.gov (United States)

    Irawan, S.; Kinif, B. I.; Bayuaji, R.

    2017-11-01

    High solid content in drilling mud may affect its properties and result in uncertainties at downhole condition. It eventually contributes to poor rig operation performance and operating cost. This research focus on developing solid control system that is suit for drilling 12.25-inch hole. The first part discussed the performance of Rate of Penetration (ROP), Equivalent Circulating Density (ECD) and drill string drag while the second part of the research discussed about the effect of solid control system performance to mud properties Plastic Viscosity (PV), Yield Point (YP) and Low-Gravity Solid (LGS). The input parameters were gathered from two different set up of solid control systems that were used in Well A and Well B. The result is mainly based on the performance of original solid control system new design versus old design. Installation of distributor tank and channel the mud to respective shale shakers significantly enhanced the system and operational performance. The ROP at 12.25-inch drilling were improved by 20%. New design improved average the ECD margin by reducing additional pressure exerted using original mud from 4.9% to 2.9%. High ECD margin is not recommended because it can break the weak formation. Mud properties while drilling the 12.25-inch hole section; PV, YP and LGS values were improved by 14 %, 17 % and 25 % respectively. Proper mud flow control and routing system at new develop design of solid control system effectively removed the solid in the drilling fluid. This improvement minimizes the tendency of frequent mud flow, screen mesh plugging and tool wear issue. Mud properties such PV, YP and LGS were maintained with an acceptable mud design envelope.

  2. Startle auditory stimuli enhance the performance of fast dynamic contractions.

    Science.gov (United States)

    Fernandez-Del-Olmo, Miguel; Río-Rodríguez, Dan; Iglesias-Soler, Eliseo; Acero, Rafael M

    2014-01-01

    Fast reaction times and the ability to develop a high rate of force development (RFD) are crucial for sports performance. However, little is known regarding the relationship between these parameters. The aim of this study was to investigate the effects of auditory stimuli of different intensities on the performance of a concentric bench-press exercise. Concentric bench-presses were performed by thirteen trained subjects in response to three different conditions: a visual stimulus (VS); a visual stimulus accompanied by a non-startle auditory stimulus (AS); and a visual stimulus accompanied by a startle auditory stimulus (SS). Peak RFD, peak velocity, onset movement, movement duration and electromyography from pectoralis and tricep muscles were recorded. The SS condition induced an increase in the RFD and peak velocity and a reduction in the movement onset and duration, in comparison with the VS and AS condition. The onset activation of the pectoralis and tricep muscles was shorter for the SS than for the VS and AS conditions. These findings point out to specific enhancement effects of loud auditory stimulation on the rate of force development. This is of relevance since startle stimuli could be used to explore neural adaptations to resistance training.

  3. Neurofeedback training of alpha-band coherence enhances motor performance.

    Science.gov (United States)

    Mottaz, Anais; Solcà, Marco; Magnin, Cécile; Corbet, Tiffany; Schnider, Armin; Guggisberg, Adrian G

    2015-09-01

    Neurofeedback training of motor cortex activations with brain-computer interface systems can enhance recovery in stroke patients. Here we propose a new approach which trains resting-state functional connectivity associated with motor performance instead of activations related to movements. Ten healthy subjects and one stroke patient trained alpha-band coherence between their hand motor area and the rest of the brain using neurofeedback with source functional connectivity analysis and visual feedback. Seven out of ten healthy subjects were able to increase alpha-band coherence between the hand motor cortex and the rest of the brain in a single session. The patient with chronic stroke learned to enhance alpha-band coherence of his affected primary motor cortex in 7 neurofeedback sessions applied over one month. Coherence increased specifically in the targeted motor cortex and in alpha frequencies. This increase was associated with clinically meaningful and lasting improvement of motor function after stroke. These results provide proof of concept that neurofeedback training of alpha-band coherence is feasible and behaviorally useful. The study presents evidence for a role of alpha-band coherence in motor learning and may lead to new strategies for rehabilitation. Copyright © 2014 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

  4. Priming of spatial distance enhances children's creative performance.

    Science.gov (United States)

    Liberman, Nira; Polack, Orli; Hameiri, Boaz; Blumenfeld, Maayan

    2012-04-01

    According to construal level theory, psychological distance promotes more abstract thought. Theories of creativity, in turn, suggest that abstract thought promotes creativity. Based on these lines of theorizing, we predicted that spatial distancing would enhance creative performance in elementary school children. To test this prediction, we primed spatial distance by presenting 6- to 9-year-olds with pictures of increasingly distal objects (from their own desk to the galaxy) or increasingly proximal objects (from the galaxy to their own desk) and then assessed the fluency and originality of their ideas in a creativity test. We found, consistent with the hypothesis, that after priming of spatial distance, compared with priming of spatial proximity, children were more creative, as reflected in higher scores of both fluency and originality. This result was not qualified by children's age or gender. Copyright © 2011 Elsevier Inc. All rights reserved.

  5. Performance of full scale enhanced reductive dechlorination in clay till

    DEFF Research Database (Denmark)

    Damgaard, Ida; Bjerg, Poul Løgstrup; Jacobsen, Carsten S.

    2013-01-01

    At a low permeability clay till site contaminated with chlorinated ethenes (Gl. Kongevej, Denmark), enhanced reductive dechlorination (ERD) was applied by direct push injection of molasses and dechlorinating bacteria. The performance was investigated by long-term groundwater monitoring, and after 4...... years of remediation, the development of degradation in the clay till matrix was investigated by high-resolution subsampling of intact cores. The formation of degradation products, the presence of specific degraders Dehalococcoides spp. with the vinyl chloride (VC) reductase gene vcrA, and the isotope...... fractionation of trichloroethene, cis-dichloroethene (cis-DCE), and VC showed that degradation of chlorinated ethenes occurred in the clay till matrix as well as in sand lenses, sand stringers, and fractures. Bioactive sections of up to 1.8 m had developed in the clay till matrix, but sections, where...

  6. Modeling track access charge to enhance railway industry performance

    Science.gov (United States)

    Berawi, Mohammed Ali; Miraj, Perdana; Berawi, Abdur Rohim Boy; Susantono, Bambang; Leviakangas, Pekka; Radiansyah, Hendra

    2017-11-01

    Indonesia attempts to improve nation's competitiveness by increasing the quality and the availability of railway network. However, the infrastructure improperly managed by the operator in terms of the technical issue. One of the reasons for this problem is an unbalanced value of infrastructure charge. In 2000's track access charge and infrastructure maintenance and operation for Indonesia railways are equal and despite current formula of the infrastructure charge, issues of transparency and accountability still in question. This research aims to produce an alternative scheme of track access charge by considering marginal cost plus markup (MC+) approach. The research combines qualitative and quantitative method through an in-depth interview and financial analysis. The result will generate alternative formula of infrastructure charge in Indonesia's railway industry. The simulation also conducted to estimate track access charge for the operator and to forecast government support in terms of subsidy. The result is expected to enhance railway industry performance and competitiveness.

  7. Enhanced performance of crumb rubber filtration for ballast water treatment.

    Science.gov (United States)

    Tang, Zhijian; Butkus, Michael A; Xie, Yuefeng F

    2009-03-01

    Waste-tire-derived crumb rubber was utilized as filter media to develop an efficient filter for ballast water treatment. In this study, the effects of coagulation, pressure filtration and dual-media (gravity) filtration on the performance of the crumb rubber filtration were investigated. The removal efficiencies of turbidity, phytoplankton and zooplankton, and head loss development were monitored during the filtration process. The addition of a coagulant enhanced the removal efficiencies of all targeted matter, but resulted in substantial increase of head loss. Pressure filtration increased filtration rates to 220 m(3)h(-1)m(-2) for 8-h operation and improved the zooplankton removal. Dual-media (crumb rubber/sand) gravity filtration also improved the removal efficiencies of phytoplankton and zooplankton over mono-media gravity crumb rubber filtration. However, these filtration techniques alone did not meet the criteria for removing indigenous organisms from ballast water. A combination of filtration and disinfection is suggested for future studies.

  8. Which one Enhances Muscular Performance in ACL Reconstructed Subjects

    Science.gov (United States)

    Harput, Gulcan; Ulusoy, Burak; Atay, Ahmet Ozgur; Baltacı, Gul

    2014-01-01

    (p=0.01). However, brace decreased VJ distance (p=0.04). Kinesiotaping had no effect on quadriceps and hamstring strength (p>0.05). Only brace increased the quadriceps strength at 180 °/s (p=0.02). 40% of the subjects felt more confident with knee brace; 25% of them were more confident with kinesiotaping and the rest (35%) of them were more confident with no brace and kinesiotaping. Conclusion: Kinesiotaping enhances balance and jump performance except for increasing knee strength in ACLR subjects at 6th months after surgery when they normally return to their sport. Although, knee brace increases quadriceps strength, it has adverse effect on functional performance . Therefore, Kinesiotaping can be applied for those patients when they start their sport specific training to enhance functional performance.

  9. Performance enhancement with supplements: incongruence between rationale and practice

    Directory of Open Access Journals (Sweden)

    Mazanov Jason

    2007-11-01

    Full Text Available Abstract Background Athletes are expected to consider multiple factors when making informed decision about nutritional supplement use. Besides rules, regulations and potential health hazards, the efficacy of different nutritional supplements in performance enhancement is a key issue. The aim of this paper was to find evidence for informed decision making by investigating the relationship between specific performance-related reasons for supplement use and the reported use of nutritional supplements. Methods The 'UK Sport 2005 Drug Free Survey' data (n = 874 were re-analysed using association [χ2] and 'strength of association' tests [ϕ] to show the proportion of informed choices and to unveil incongruencies between self-reported supplement use and the underlying motives. Results Participants (n = 520 reported supplement use in the pattern of: vitamin C (70.4%, creatine (36.1%, whey protein (30.6%, iron (29.8%, caffeine (23.8%, and ginseng (8.3% for the following reasons: strength maintenance (38.1%, doctors' advice (24.2%, enhancing endurance (20.0%, ability to train longer (13.3%, and provided by the governing body (3.8%. Of thirty possible associations between the above supplements and reasons, 11 were predictable from literature precedents and only 8 were evidenced and these were not strong (ϕ 2 = 49.14, p 2 = 97.08, p 2 = 97.82, p Conclusion This study provided a platform for assessing congruence between athletes' reasons for supplement use and their actual use. These results suggest that a lack of understanding exists in supplement use. There is an urgent need to provide accurate information which will help athletes make informed choices about the use of supplements.

  10. Tablet computer enhanced training improves internal medicine exam performance.

    Science.gov (United States)

    Baumgart, Daniel C; Wende, Ilja; Grittner, Ulrike

    2017-01-01

    Traditional teaching concepts in medical education do not take full advantage of current information technology. We aimed to objectively determine the impact of Tablet PC enhanced training on learning experience and MKSAP® (medical knowledge self-assessment program) exam performance. In this single center, prospective, controlled study final year medical students and medical residents doing an inpatient service rotation were alternatingly assigned to either the active test (Tablet PC with custom multimedia education software package) or traditional education (control) group, respectively. All completed an extensive questionnaire to collect their socio-demographic data, evaluate educational status, computer affinity and skills, problem solving, eLearning knowledge and self-rated medical knowledge. Both groups were MKSAP® tested at the beginning and the end of their rotation. The MKSAP® score at the final exam was the primary endpoint. Data of 55 (tablet n = 24, controls n = 31) male 36.4%, median age 28 years, 65.5% students, were evaluable. The mean MKSAP® score improved in the tablet PC (score Δ + 8 SD: 11), but not the control group (score Δ- 7, SD: 11), respectively. After adjustment for baseline score and confounders the Tablet PC group showed on average 11% better MKSAP® test results compared to the control group (pmedical problem solving were journal articles looked up on PubMed or Google®, and books. Our study provides evidence, that tablet computer based integrated training and clinical practice enhances medical education and exam performance. Larger, multicenter trials are required to independently validate our data. Residency and fellowship directors are encouraged to consider adding portable computer devices, multimedia content and introduce blended learning to their respective training programs.

  11. Mixed-List Phonological Similarity Effects in Delayed Serial Recall

    Science.gov (United States)

    Farrell, Simon

    2006-01-01

    Recent experiments have shown that placing dissimilar items on lists of phonologically similar items enhances accuracy of ordered recall of the dissimilar items [Farrell, S., & Lewandowsky, S. (2003). Dissimilar items benefit from phonological similarity in serial recall. "Journal of Experimental Psychology: Learning, Memory, and Cognition," 29,…

  12. Effects of Age on Serial Recall of Natural and Synthetic Speech

    OpenAIRE

    Humes, Larry E.; Nelson, Kathleen J.; Pisoni, David B.; Lively, Scott E.

    1993-01-01

    The present study addressed the effects of aging on auditory serial-recall performance for natural and synthetic words. Word difficulty, measured in terms of frequency of occurrence and phonological similarity, and rate of presentation were also manipulated in an effort to determine which processes underlying serial-recall performance, if any, were affected by aging. Results indicated that age per se had little effect on short-term (working) memory as measured by the serial recall of monosyll...

  13. Enhancement of graphene thermoelectric performance through defect engineering

    Science.gov (United States)

    Anno, Yuki; Imakita, Yuki; Takei, Kuniharu; Akita, Seiji; Arie, Takayuki

    2017-06-01

    Thermoelectric properties of materials are typically evaluated using the figure of merit, ZT, which relies on both the electrical and thermal properties of the materials. Although graphene has a high thermoelectric power factor, its overall ZT value is quite low as it possesses extremely high thermal conductivity. Phonons are the main heat carrier in graphene, and therefore propagation of heat in the material may be modulated by introducing defects into the structure, resulting in reduced thermal conductivity. In this study, we investigate the effect of graphene defect density on the thermoelectric performance of graphene. The defects introduced into graphene by oxygen plasma treatment reduce its Seebeck coefficient as well as its electrical conductivity; as a result, the thermoelectric power factor declines with increasing defect density. However, at higher defect densities, the reduction in thermal conductivity dominates over the reduction in electrical conductivity and, consequently, graphene treated in this way is observed to possess ZT values of up to three times that of pristine graphene. Therefore, it may be concluded that introducing controlled amount of defects into graphene is an effective way of reducing its thermal conductivity, thereby enhancing the performance of graphene-based thermoelectric devices.

  14. New Star-Like Surfacetexture for Enhanced Hydrodynamic Lubrication Performance

    Directory of Open Access Journals (Sweden)

    Uddin M.S.

    2017-09-01

    Full Text Available This paper presents a numerical modelling and optimization of a new ‘star-like’ geometric texture shape with an aim to improve tribological performance. Initial studies showed that the triangle effect is the most dominant in reducing the friction. Motivated with this, a ‘star-like’ texture shape consisting of a series of triangular spikes around the centre of the texture is proposed. It is hypothesised that by increasing the triangular effect on a texture shape, the converging micro-wedge effect is expected to increase, hence increasing the film pressure and reducing the friction. Using the well-known Reynolds boundary conditions, numerical modelling of surface texturing is implemented via finite difference method. Simulation results showed that the number of apex points of the new ‘star-like’ texture has a significant effect on the film pressure and the friction coefficient. A 6-pointed texture at a texture density of 0.4 is shown to be the optimum shape. The new optimum star-like texture reduces the friction coefficient by 80%, 64.39%, 19.32% and 16.14%, as compared to ellipse, chevron, triangle and circle, respectively. This indicates the potential benefit of the proposed new shape in further enhancing the hydrodynamic lubrication performance of slider bearing contacts.

  15. Enhanced detection performance in electrosense through capacitive sensing.

    Science.gov (United States)

    Bai, Yang; Neveln, Izaak D; Peshkin, Michael; MacIver, Malcolm A

    2016-08-08

    Weakly electric fish emit an AC electric field into the water and use thousands of sensors on the skin to detect field perturbations due to surrounding objects. The fish's active electrosensory system allows them to navigate and hunt, using separate neural pathways and receptors for resistive and capacitive perturbations. We have previously developed a sensing method inspired by the weakly electric fish to detect resistive perturbations and now report on an extension of this system to detect capacitive perturbations as well. In our method, an external object is probed by an AC field over multiple frequencies. We present a quantitative framework that relates the response of a capacitive object at multiple frequencies to the object's composition and internal structure, and we validate this framework with an electrosense robot that implements our capacitive sensing method. We define a metric for comparing the electrosensory range of different underwater electrosense systems. For detecting non-conductive objects, we show that capacitive sensing performs better than resistive sensing by almost an order of magnitude using this measure, while for conductive objects there is a four-fold increase in performance. Capacitive sensing could therefore provide electric fish with extended sensing range for capacitive objects such as prey, and gives artificial electrolocation systems enhanced range for targets that are capacitive.

  16. Morphology optimization for enhanced performance in organic photovoltaics

    Science.gov (United States)

    Wodo, Olga; Zola, Jaroslaw; Ganapathysubramanian, Baskar

    2015-03-01

    Organic solar cells have the potential for widespread usage due to their low cost-per-watt and mechanical flexibility. Their wide spread use, however, is bottlenecked primarily by their low solar efficiencies. Experimental evidence suggests that a key property determining the solar efficiency of such devices is the final morphological distribution of the electron-donor and electron-acceptor constituents. By carefully designing the morphology of the device, one could potentially significantly enhance their performance. This is an area of intense experimental effort that is mostly trial-and-error based, and serves as a fertile area for introducing mechanics and computational thinking. In this work, we use optimization techniques coupled with computational modeling to identify the optimal structures for high efficiency solar cells. In particular, we use adaptive population-based incremental learning method linked to graph-based surrogate model to evaluate properties for given structure. We study several different criterions and find optimal structure that that improve the performance of currently hypothesized optimal structures by 29%.

  17. Music enhances performance and perceived enjoyment of sprint interval exercise.

    Science.gov (United States)

    Stork, Matthew J; Kwan, Matthew Y W; Gibala, Martin J; Martin Ginis, Kathleen A

    2015-05-01

    Interval exercise training can elicit physiological adaptations similar to those of traditional endurance training, but with reduced time. However, the intense nature of specific protocols, particularly the "all-out" efforts characteristic of sprint interval training (SIT), may be perceived as being aversive. The purpose of this study was to determine whether listening to self-selected music can reduce the potential aversiveness of an acute session of SIT by improving affect, motivation, and enjoyment, and to examine the effects of music on performance. Twenty moderately active adults (22 ± 4 yr) unfamiliar with interval exercise completed an acute session of SIT under two different conditions: music and no music. The exercise consisted of four 30-s "all-out" Wingate Anaerobic Test bouts on a cycle ergometer, separated by 4 min of rest. Peak and mean power output, RPE, affect, task motivation, and perceived enjoyment of the exercise were measured. Mixed-effects models were used to evaluate changes in dependent measures over time and between the two conditions. Peak and mean power over the course of the exercise session were higher in the music condition (coefficient = 49.72 [SE = 13.55] and coefficient = 23.65 [SE = 11.30]; P music condition (coefficient = 7.00 [SE = 3.05]; P Music enhances in-task performance and enjoyment of an acute bout of SIT. Listening to music during intense interval exercise may be an effective strategy for facilitating participation in, and adherence to, this form of training.

  18. Role of nutrition in performance enhancement and postexercise recovery

    Directory of Open Access Journals (Sweden)

    Beck KL

    2015-08-01

    Full Text Available Kathryn L Beck,1 Jasmine S Thomson,2 Richard J Swift,1 Pamela R von Hurst11School of Food and Nutrition, Massey Institute of Food Science and Technology, College of Health, Massey University Albany, Auckland, 2School of Food and Nutrition, Massey Institute of Food Science and Technology, College of Health, Massey University Manawatu, Palmerston North, New ZealandAbstract: A number of factors contribute to success in sport, and diet is a key component. An athlete's dietary requirements depend on several aspects, including the sport, the athlete's goals, the environment, and practical issues. The importance of individualized dietary advice has been increasingly recognized, including day-to-day dietary advice and specific advice before, during, and after training and/or competition. Athletes use a range of dietary strategies to improve performance, with maximizing glycogen stores a key strategy for many. Carbohydrate intake during exercise maintains high levels of carbohydrate oxidation, prevents hypoglycemia, and has a positive effect on the central nervous system. Recent research has focused on athletes training with low carbohydrate availability to enhance metabolic adaptations, but whether this leads to an improvement in performance is unclear. The benefits of protein intake throughout the day following exercise are now well recognized. Athletes should aim to maintain adequate levels of hydration, and they should minimize fluid losses during exercise to no more than 2% of their body weight. Supplement use is widespread in athletes, with recent interest in the beneficial effects of nitrate, beta-alanine, and vitamin D on performance. However, an unregulated supplement industry and inadvertent contamination of supplements with banned substances increases the risk of a positive doping result. Although the availability of nutrition information for athletes varies, athletes will benefit from the advice of a registered dietician or nutritionist

  19. High-intensity re-warm-ups enhance soccer performance.

    Science.gov (United States)

    Zois, J; Bishop, D; Fairweather, I; Ball, K; Aughey, R J

    2013-09-01

    The effects of high-intensity, short-duration, re-warm-ups on team-sport-related performance were investigated. In a randomised, cross-over study, participants performed 2×26-min periods of an intermittent activity protocol (IAP) on a non-motorized treadmill, interspersed by 15-min of passive recovery (CON); 3-min small-sided game (SSG); or a 5RM leg-press. Measures included counter-movement jump, repeated-sprint, the Loughborough soccer passing test (LSPT), blood lactate concentration, heart-rate, and perceptual measures. Data were analyzed using effect size (90% confidence intervals), and percentage change; determining magnitudes of effects. A 5RM re-warm-up improved flight-time to contraction-time ratio when compared to SSG (9.8%, ES; 0.5±0.3) and CON (ES: 9.4%, 0.7±0.5) re-warm-ups, remaining higher following the second IAP (8.8%, ES; 0.5±0.3 and 10.2%, ES; 0.6±0.6, respectively). Relative-maximum rate-of-force development was greater in the 5RM condition following the second IAP compared to SSG (29.3%, ES; 0.7±0.5) and CON (16.2%, ES; 0.6±0.6). Repeated-sprint ability during the second IAP improved in the 5RM re-warm-up; peak velocity, mean velocity, and acceleration were 4, 3, and 18% greater, respectively. Within groups, the SSG re-warm-up improved LSPT performance post-intervention; 6.4% (ES: 0.6±0.8) and following the second IAP 6.2% (ES: 0.6±0.6), compared to pre-intervention. A 5RM leg-press re-warm-up improved physical performance, while a SSG re-warm-up enhanced skill execution following standardized intermittent exercise. © Georg Thieme Verlag KG Stuttgart · New York.

  20. Enhancing ROC performance of trustworthy camera source identification

    Science.gov (United States)

    Kang, Xiangui; Li, Yinxiang; Qu, Zhenhua; Huang, Jiwu

    2011-02-01

    Sensor pattern noise (SPN) extracted from digital images has been proved to be a unique fingerprint of digital camera. However, sensor pattern noise can be contaminated largely in frequency domain by image detail from scene according to Li's work and non-unique artifacts of on-sensor signal transfer, sensor design, color interpolation according to Chen et al's work, the source camera identification performance based on SPN needs to be improved especially for small image block. Motivated by their works, in order to lessen the effect of these contaminations, the unique SPN fingerprint for identifying one specific camera is assumed to be a white noise which has a flat frequency spectrum, so the SPN extracted from an image is whitened first to have a flat frequency spectrum, then inputted to the mixed correlation detector. Source camera identification is the detection of the existence of the camera reference SPN in the SPN extracted from a single image. Compared with the correlation detection approach and Li's model based approaches on 7 cameras, 1400 photos totally, each camera is responsible for 200, the experimental results show that the proposed mixed correlation detection enhances the receiver operating characteristic (ROC) performance of source camera identification, especially greatly raises the detection rate (true positive rate) in the case of trustworthy identification which is with a low false positive rate. For example, the proposed mixed correlation detection raises the true positive rate from 78% to 93% at zero false positive rate on image blocks of 256x256 pixels cropped from the center of the 1400 photos. The proposed mixed correlation detection also has large advantage to resist JPEG compression with low quality factor. Fridrich's group has proposed two reference SPN extraction methods which are the noise residues averaging and the maximum likelihood estimation method. They are compared from the aspect of ROC performance associated with the correlation

  1. Malingering, coaching, and the serial position effect.

    Science.gov (United States)

    Suhr, Julie A

    2002-01-01

    The normal pattern of performance on list-learning tasks is to recall more words from the beginning (primacy) and end (recency) of the list. This pattern is also seen in patients with closed head injury, but malingerers tend to recall less words from the beginning of word lists, leading to a suppressed primacy effect. The present study examined this pattern on both learning trials and delayed recall of the Auditory Verbal Learning Test (AVLT) in 34 persons performing with normal effort, 38 naive malingerers, 33 warned malingerers, and 29 head-injured patients. Both malingering groups had lower scores on the primacy portion of the list during learning trials, while normals and head-injured patients had normal serial position curves. During delayed recall, normals and head-injured patients did better than the two malingering groups on middle and recency portions of the list. Findings suggest that the serial position effect during learning trials may be a useful pattern of performance to watch for when suspicious of malingering.

  2. Novel ketone diet enhances physical and cognitive performance.

    Science.gov (United States)

    Murray, Andrew J; Knight, Nicholas S; Cole, Mark A; Cochlin, Lowri E; Carter, Emma; Tchabanenko, Kirill; Pichulik, Tica; Gulston, Melanie K; Atherton, Helen J; Schroeder, Marie A; Deacon, Robert M J; Kashiwaya, Yoshihiro; King, M Todd; Pawlosky, Robert; Rawlins, J Nicholas P; Tyler, Damian J; Griffin, Julian L; Robertson, Jeremy; Veech, Richard L; Clarke, Kieran

    2016-12-01

    Ketone bodies are the most energy-efficient fuel and yield more ATP per mole of substrate than pyruvate and increase the free energy released from ATP hydrolysis. Elevation of circulating ketones via high-fat, low-carbohydrate diets has been used for the treatment of drug-refractory epilepsy and for neurodegenerative diseases, such as Parkinson's disease. Ketones may also be beneficial for muscle and brain in times of stress, such as endurance exercise. The challenge has been to raise circulating ketone levels by using a palatable diet without altering lipid levels. We found that blood ketone levels can be increased and cholesterol and triglycerides decreased by feeding rats a novel ketone ester diet: chow that is supplemented with (R)-3-hydroxybutyl (R)-3-hydroxybutyrate as 30% of calories. For 5 d, rats on the ketone diet ran 32% further on a treadmill than did control rats that ate an isocaloric diet that was supplemented with either corn starch or palm oil (P diets, making more correct decisions before making a mistake (P diet had greater free energy available from ATP hydrolysis during increased work than did hearts from rats on the other diets as shown by using [(31)P]-NMR spectroscopy. The novel ketone diet, therefore, improved physical performance and cognitive function in rats, and its energy-sparing properties suggest that it may help to treat a range of human conditions with metabolic abnormalities.-Murray, A. J., Knight, N. S., Cole, M. A., Cochlin, L. E., Carter, E., Tchabanenko, K., Pichulik, T., Gulston, M. K., Atherton, H. J., Schroeder, M. A., Deacon, R. M. J., Kashiwaya, Y., King, M. T., Pawlosky, R., Rawlins, J. N. P., Tyler, D. J., Griffin, J. L., Robertson, J., Veech, R. L., Clarke, K. Novel ketone diet enhances physical and cognitive performance. © The Author(s).

  3. A New Metasurface Superstrate Structure for Antenna Performance Enhancement.

    Science.gov (United States)

    Islam, Mohammad Tariqul; Ullah, Mohammad Habib; Singh, Mandeep Jit; Faruque, Mohammad Rashed Iqbal

    2013-07-31

    A new metasurface superstrate structure (MSS)-loaded dual band microstrip line-fed small patch antenna is presented in this paper. The proposed antenna was designed on a ceramic-filled bioplastic sandwich substrate with a high dielectric constant. The proposed 7 × 6 element, square-shaped, single-sided MSS significantly improved the bandwidth and gain of the proposed antenna. The proposed MSS incorporated a slotted patch antenna that effectively increased the measured operating bandwidth from 13.3% to 18.8% and from 14.8% to 23.2% in the lower and upper bands, respectively. Moreover, the average gain of the proposed MSS-based antenna was enhanced from 2.12 dBi to 3.02 dBi in the lower band and from 4.10 dBi to 5.28 dBi in the upper band compared to the patch antenna alone. In addition to the bandwidth and gain improvements, more directive radiation characteristics were also observed from the MSS antenna compared to the patch itself. The effects of the MSS elements and the ground plane length on the reflection coefficient of the antenna were analyzed and optimized. The overall performance makes the proposed antenna appropriate for RFID and WLAN applications.

  4. Performance Analysis of TCP Enhancements in Satellite Data Networks

    Science.gov (United States)

    Broyles, Ren H.

    1999-01-01

    This research examines two proposed enhancements to the well-known Transport Control Protocol (TCP) in the presence of noisy communication links. The Multiple Pipes protocol is an application-level adaptation of the standard TCP protocol, where several TCP links cooperate to transfer data. The Space Communication Protocol Standard - Transport Protocol (SCPS-TP) modifies TCP to optimize performance in a satellite environment. While SCPS-TP has inherent advantages that allow it to deliver data more rapidly than Multiple Pipes, the protocol, when optimized for operation in a high-error environment, is not compatible with legacy TCP systems, and requires changes to the TCP specification. This investigation determines the level of improvement offered by SCPS-TP's Corruption Mode, which will help determine if migration to the protocol is appropriate in different environments. As the percentage of corrupted packets approaches 5 %, Multiple Pipes can take over five times longer than SCPS-TP to deliver data. At high error rates, SCPS-TP's advantage is primarily caused by Multiple Pipes' use of congestion control algorithms. The lack of congestion control, however, limits the systems in which SCPS-TP can be effectively used.

  5. Specific inspiratory muscle warm-up enhances badminton footwork performance.

    Science.gov (United States)

    Lin, Hua; Tong, Tom Kwokkeung; Huang, Chuanye; Nie, Jinlei; Lu, Kui; Quach, Binh

    2007-12-01

    The effects of inspiratory muscle (IM) warm-up on IM function and on the maximum distance covered in a subsequent incremental badminton-footwork test (FWmax) were examined. Ten male badminton players were recruited to perform identical tests in three different trials in a random order. The control trial did not involve an IM warm-up, whereas the placebo and experimental trials did involve an IM warm-up consisting of two sets of 30-breath manoeuvres with an inspiratory pressure-threshold load equivalent to 15% (PLA) and 40% (IMW) maximum inspiratory mouth pressure, respectively. In the IMW trial, IM function was improved with 7.8%+/-4.0% and 6.9%+/-3.5% increases from control found in maximal inspiratory pressure at zero flow (P0) and maximal rate of P0 development (MRPD), respectively (pbadminton-footwork test. The improved footwork was partly attributable to the reduced breathless sensation resulting from the enhanced IM function, whereas the contribution of the concomitant reduction in [La-]b accumulation was relatively minor.

  6. High performance metamaterial device with enhanced electromagnetic energy harvesting efficiency

    Science.gov (United States)

    Shang, Shuai; Yang, Shizhong; Shan, Meng; Liu, Jing; Cao, Hailin

    2017-10-01

    A high performance metamaterial device for electromagnetic energy harvesting is presented. The unit cell of the metamaterial device consists of four identical omega ring resonators arranged in rotational symmetry, and each omega ring is loaded with a 50 Ω resistor that mimics the input impedance of a rectifier circuit. A proof-of-concept prototype is designed for operation at the frequency of 5.8 GHz. Here, the efficient energy harvesting is validated by the energy dissipated in each resistor. Based on the full absorption concept, the metamaterial device achieves a harvesting efficiency up to 93.1% under normal incidence. In addition, the energy harvester shows polarization independent and wide-angle incident frequency responses with good harvesting characteristics over the entire operating range. The surface current distribution is analyzed to gain an insight into the energy harvesting mechanism. Moreover, the harvester prototype is manufactured and measured, and the simulated and measured results are in good agreement. Due to the enhanced electromagnetic energy harvesting efficiency, the proposed device is a good candidate for microwave power transmission.

  7. A New Metasurface Superstrate Structure for Antenna Performance Enhancement

    Directory of Open Access Journals (Sweden)

    Mohammad Rashed Iqbal Faruque

    2013-07-01

    Full Text Available A new metasurface superstrate structure (MSS-loaded dual band microstrip line-fed small patch antenna is presented in this paper. The proposed antenna was designed on a ceramic-filled bioplastic sandwich substrate with a high dielectric constant. The proposed 7 × 6 element, square-shaped, single-sided MSS significantly improved the bandwidth and gain of the proposed antenna. The proposed MSS incorporated a slotted patch antenna that effectively increased the measured operating bandwidth from 13.3% to 18.8% and from 14.8% to 23.2% in the lower and upper bands, respectively. Moreover, the average gain of the proposed MSS-based antenna was enhanced from 2.12 dBi to 3.02 dBi in the lower band and from 4.10 dBi to 5.28 dBi in the upper band compared to the patch antenna alone. In addition to the bandwidth and gain improvements, more directive radiation characteristics were also observed from the MSS antenna compared to the patch itself. The effects of the MSS elements and the ground plane length on the reflection coefficient of the antenna were analyzed and optimized. The overall performance makes the proposed antenna appropriate for RFID and WLAN applications.

  8. Enhancement of Ultrahigh Performance Concrete Material Properties with Carbon Nanofiber

    Directory of Open Access Journals (Sweden)

    Libya Ahmed Sbia

    2014-01-01

    Full Text Available Ultrahigh performance concrete (UHPC realized distinctly high mechanical, impermeability, and durability characteristics by reducing the size and content of capillary pore, refining the microstructure of cement hydrates, and effectively using fiber reinforcement. The dense and fine microstructure of UHPC favor its potential to effectively disperse and interact with nanomaterials, which could complement the reinforcing action of fibers in UHPC. An optimization experimental program was implemented in order to identify the optimum combination of steel fiber and relatively low-cost carbon nanofiber in UHPC. The optimum volume fractions of steel fiber and carbon nanofiber identified for balanced improvement of flexural strength, ductility, energy sorption capacity, impact, and abrasion resistance of UHPC were 1.1% and 0.04%, respectively. Desired complementary/synergistic actions of nanofibers and steel fibers in UHPC were detected, which were attributed to their reinforcing effects at different scales, and the potential benefits of nanofibers to interfacial bonding and pull-out behavior of fibers in UHPC. Modification techniques which enhanced the hydrophilicity and bonding potential of nanofibers to cement hydrates benefited their reinforcement efficiency in UHPC.

  9. Caffeine: Cognitive and Physical Performance Enhancer or Psychoactive Drug?

    Science.gov (United States)

    Cappelletti, Simone; Daria, Piacentino; Sani, Gabriele; Aromatario, Mariarosaria

    2015-01-01

    Caffeine use is increasing worldwide. The underlying motivations are mainly concentration and memory enhancement and physical performance improvement. Coffee and caffeine-containing products affect the cardiovascular system, with their positive inotropic and chronotropic effects, and the central nervous system, with their locomotor activity stimulation and anxiogenic-like effects. Thus, it is of interest to examine whether these effects could be detrimental for health. Furthermore, caffeine abuse and dependence are becoming more and more common and can lead to caffeine intoxication, which puts individuals at risk for premature and unnatural death. The present review summarizes the main findings concerning caffeine’s mechanisms of action (focusing on adenosine antagonism, intracellular calcium mobilization, and phosphodiesterases inhibition), use, abuse, dependence, intoxication, and lethal effects. It also suggests that the concepts of toxic and lethal doses are relative, since doses below the toxic and/or lethal range may play a causal role in intoxication or death. This could be due to caffeine’s interaction with other substances or to the individuals' preexisting metabolism alterations or diseases. PMID:26074744

  10. The use of genes for performance enhancement: doping or therapy?

    Directory of Open Access Journals (Sweden)

    R.S. Oliveira

    2011-12-01

    Full Text Available Recent biotechnological advances have permitted the manipulation of genetic sequences to treat several diseases in a process called gene therapy. However, the advance of gene therapy has opened the door to the possibility of using genetic manipulation (GM to enhance athletic performance. In such ‘gene doping’, exogenous genetic sequences are inserted into a specific tissue, altering cellular gene activity or leading to the expression of a protein product. The exogenous genes most likely to be utilized for gene doping include erythropoietin (EPO, vascular endothelial growth factor (VEGF, insulin-like growth factor type 1 (IGF-1, myostatin antagonists, and endorphin. However, many other genes could also be used, such as those involved in glucose metabolic pathways. Because gene doping would be very difficult to detect, it is inherently very attractive for those involved in sports who are prepared to cheat. Moreover, the field of gene therapy is constantly and rapidly progressing, and this is likely to generate many new possibilities for gene doping. Thus, as part of the general fight against all forms of doping, it will be necessary to develop and continually improve means of detecting exogenous gene sequences (or their products in athletes. Nevertheless, some bioethicists have argued for a liberal approach to gene doping.

  11. Caffeine: cognitive and physical performance enhancer or psychoactive drug?

    Science.gov (United States)

    Cappelletti, Simone; Piacentino, Daria; Daria, Piacentino; Sani, Gabriele; Aromatario, Mariarosaria

    2015-01-01

    Caffeine use is increasing worldwide. The underlying motivations are mainly concentration and memory enhancement and physical performance improvement. Coffee and caffeine-containing products affect the cardiovascular system, with their positive inotropic and chronotropic effects, and the central nervous system, with their locomotor activity stimulation and anxiogenic-like effects. Thus, it is of interest to examine whether these effects could be detrimental for health. Furthermore, caffeine abuse and dependence are becoming more and more common and can lead to caffeine intoxication, which puts individuals at risk for premature and unnatural death. The present review summarizes the main findings concerning caffeine's mechanisms of action (focusing on adenosine antagonism, intracellular calcium mobilization, and phosphodiesterases inhibition), use, abuse, dependence, intoxication, and lethal effects. It also suggests that the concepts of toxic and lethal doses are relative, since doses below the toxic and/or lethal range may play a causal role in intoxication or death. This could be due to caffeine's interaction with other substances or to the individuals' preexisting metabolism alterations or diseases.

  12. The Serial Process in Visual Search

    Science.gov (United States)

    Gilden, David L.; Thornton, Thomas L.; Marusich, Laura R.

    2010-01-01

    The conditions for serial search are described. A multiple target search methodology (Thornton & Gilden, 2007) is used to home in on the simplest target/distractor contrast that effectively mandates a serial scheduling of attentional resources. It is found that serial search is required when (a) targets and distractors are mirror twins, and…

  13. Serial killer: il database mondiale

    Directory of Open Access Journals (Sweden)

    Gaetano parente

    2016-07-01

    Full Text Available The complex and multisided study of serial killers is partly made difficult by the current level of progress that has led these deviant people to evolve in relation to the aspects of shrewdness (concerning the staging and mobility. Despite the important work of some scholars who proposed important theories, all this shows that, concerning serial murders, it is still particularly frequent not to pay attention to links among homicides committed by the same person but in different parts of the world. It is therefore crucial to develop a worldwide database that allows all police forces to access information collected on crime scenes of murders which are particularly absurd and committed without any apparent reason. It will then be up to the profiler, through ad hoc and technologically advanced tools, to collect this information on the crime scene that would be made available to all police forces thanks to the worldwide database.

  14. The sexually sadistic serial killer.

    Science.gov (United States)

    Warren, J I; Hazelwood, R R; Dietz, P E

    1996-11-01

    This article explores characteristics and crime scene behavior of 20 sexually sadistic serial murderers. The pairing of character pathology with paraphilic arousal to the control and degradation of others is examined as it manifests itself in their murders. Commonalities across murders and across murderers are highlighted, i.e., the execution of murders that are well-planned, the use of preselected locations, captivity, a variety of painful sexual acts, sexual bondage, intentional torture, and death by means of strangulation and stabbing.

  15. IRIG Serial Time Code Formats

    Science.gov (United States)

    2016-08-01

    and G. It should be noted that this standard reflects the present state of the art in serial time code formatting and is not intended to constrain...separation for visual resolution. The LSB occurs first except for the fractional seconds subword that follows the day-of-year subword. The BCD TOY code...and P6 to complete the BCD time code word. An index marker occurs between the decimal digits in each subword to provide separation for visual

  16. Benefits of Blocked Over Serial Feedback on Complex Motor Skill Learning.

    Science.gov (United States)

    Wulf, Gabriele; Hörger, Monika; Shea, Charles H.

    1999-03-01

    The effects of blocked versus serial feedback (FB) on the learning of a complex motor skill-the production of slalom-type movements on a ski-simulator-were examined. FB was given about force onset, which is considered to be a measure of movement efficiency; relatively late force onsets characterize expert performance. One group of participants (blocked FB; n = 10) received FB about 1 foot per day; for example, for the right foot on Days 1 and 3 and for the left foot on Days 2 and 4. For another group (serial FB; n = 10), the foot about which FB was received was switched on consecutive trials on each of 4 days of practice. Learning was assessed on no-FB trials at the beginning of Days 2, 3, and 4, and on Day 5. Even though there were no differences between groups in force onset, the blocked FB group produced significantly larger movement amplitudes and higher movement frequencies than the serial FB group on the retention test on Day 5. Thus, contrary to the learning of more simple skills (e.g., T. D. Lee & H. Carnahan, 1990), constantly changing the movement component that FB is provided about did not seem to be beneficial for the learning of more complex skills. The findings add to the increasing evidence showing that practice variables that have been shown to enhance the learning of simple skills can actually be detrimental to the learning of complex skills.

  17. Serial position effects in recognition memory for odors: a reexamination.

    Science.gov (United States)

    Miles, Christopher; Hodder, Kathryn

    2005-10-01

    Seven experiments examined recognition memory for sequentially presented odors. Following Reed (2000), participants were presented with a sequence of odors and then required to identify an odor from the sequence in a test probe comprising 2 odors. The pattern of results obtained by Reed (2000, although statistically marginal) demonstrated enhanced recognition for odors presented at the start (primacy) and end (recency) of the sequence: a result that we failed to replicate in any of the experiments reported here. Experiments 1 and 3 were designed to replicate Reed (2000), employing five-item and seven-item sequences, respectively, and each demonstrated significant recency, with evidence of primacy in Experiment 3 only. Experiment 2 replicated Experiment 1, with reduced interstimulus intervals, and produced a null effect of serial position. The ease with which the odors could be verbally labeled was manipulated in Experiments 4 and 5. Nameable odors produced a null effect of serial position (Experiment 4), and hard-to-name odors produced a pronounced recency effect (Experiment 5); nevertheless, overall rates of recognition were remarkably similar for the two experiments at around 70%. Articulatory suppression reduced recognition accuracy (Experiment 6), but recency was again present in the absence of primacy. Odor recognition performance was immune to the effects of an interleaved odor (Experiment 7), and, again, both primacy and recency effects were absent. There was no evidence of olfactory fatigue: Recognition accuracy improved across trials (Experiment 1). It is argued that the results of the experiments reported here are generally consistent with that body of work employing hard-to-name visual stimuli, where recency is obtained in the absence of primacy when the retention interval is short.

  18. Organic solar cells: Degradation processes and approaches to enhance performance

    Science.gov (United States)

    Fungura, Fadzai

    Organic solar cells (OSCs) have attracted a lot of attention due to their potential as flexible, lightweight, and low-cost renewable energy sources. Significant improvements have been made in increasing the devices' power conversion efficiency (PCE) and extensive efforts to understand degradation mechanisms and increase OSCs' lifetimes are ongoing. OSCs with higher than 10% efficiency have been reported. Enhanced stability and efficiency of inverted poly(3-hexylthiophene) (P3HT) solar cells with Cesium (Cs) halides were achieved by spin-coating Bphen (4,7-di(phenyl)-1,10-phenanthroline) on the halide layer and adding an 100nm polystyrene beads layer on the blank side of the OSC. To investigate photodegradation in a low-bandgap polymer, PBDTTT-EFT (benzo[1,2-b:4,5-b']dithiophene (BDT) and thieno[3,4-b]-thiophene), PBDTTT-EFT:PCBM bulk heterojunction (BHJ) solar cells were irradiated under 1X sun intensity and their electronic measurements were monitored over time. The electronic measurements revealed an increase in deep defect density in the polymer and at the donor-acceptor (D/A) interface of BHJ SCs and an increase in charge recombination as well as a decrease in external quantum efficiency, charge collection, short circuit current, open circuit voltage and hole mobility. Filtering blue and UV light resulted in drastically reduced photodegradation. Electron paramagnetic resonance measurements were performed on the photodegraded polymer and BHJ films, and revealed for the first time experimental evidence for metastable carbon dangling bonds (g=2.0029+/-0.0004) formed by blue/UV irradiation of the films. Dark EPR showed an increase in densities of other spin-active sites in the polymer, fullerene and polymer:fullerene blends in agreement with electronic measurements. The EPR results revealed that the carbon dangling bonds were at the D/A interface. These studies helped to better understand degradation mechanisms in a low-bandgap polymer, PBDTTT-EFT, ways to enhance

  19. Serial murder by healthcare professionals.

    Science.gov (United States)

    Yorker, Beatrice Crofts; Kizer, Kenneth W; Lampe, Paula; Forrest, A R W; Lannan, Jacquetta M; Russell, Donna A

    2008-01-01

    The prosecution of Charles Cullen, a nurse who killed at least 40 patients over a 16-year period, highlights the need to better understand the phenomenon of serial murder by healthcare professionals. The authors conducted a LexisNexis search which yielded 90 criminal prosecutions of healthcare providers that met inclusion criteria for serial murder of patients. In addition we reviewed epidemiologic studies, toxicology evidence, and court transcripts, to provide data on healthcare professionals who have been prosecuted between 1970 and 2006. Fifty-four of the 90 have been convicted; 45 for serial murder, four for attempted murder, and five pled guilty to lesser charges. Twenty-four more have been indicted and are either awaiting trial or the outcome has not been published. The other 12 prosecutions had a variety of legal outcomes. Injection was the main method used by healthcare killers followed by suffocation, poisoning, and tampering with equipment. Prosecutions were reported from 20 countries with 40% taking place in the United States. Nursing personnel comprised 86% of the healthcare providers prosecuted; physicians 12%, and 2% were allied health professionals. The number of patient deaths that resulted in a murder conviction is 317 and the number of suspicious patient deaths attributed to the 54 convicted caregivers is 2113. These numbers are disturbing and demand that systemic changes in tracking adverse patient incidents associated with presence of a specific healthcare provider be implemented. Hiring practices must shift away from preventing wrongful discharge or denial of employment lawsuits to protecting patients from employees who kill.

  20. Notorious Cases of Serial Killers

    Directory of Open Access Journals (Sweden)

    Iosub Elena-Cătălina

    2014-05-01

    Full Text Available The reconstruction of a death scene provides an overall picture of the crime and will indicate the murder as an event or one of a series of events and also the criminal. But when the criminal is declared a serial killer, many questions are raised up. How could a person kill some else without a reason or why people react in such a disorganized way and become so brutal or what made them act like that and so many questions with also so many answers. This project explains the psychology of a murderer, his own way of thinking and acting by presuming that we may accurately discover what is in their minds when they kill. It is about a very complex issue regarding murder investigations, biological factors and psychological profile of a serial killer. Dealing with this problem we will at last reach to the question that could solve finally the puzzle: ―Are serial murderers distorted reflections of society's own values?

  1. Serial recall of colors: Two models of memory for serial order applied to continuous visual stimuli.

    Science.gov (United States)

    Peteranderl, Sonja; Oberauer, Klaus

    2018-01-01

    This study investigated the effects of serial position and temporal distinctiveness on serial recall of simple visual stimuli. Participants observed lists of five colors presented at varying, unpredictably ordered interitem intervals, and their task was to reproduce the colors in their order of presentation by selecting colors on a continuous-response scale. To control for the possibility of verbal labeling, articulatory suppression was required in one of two experimental sessions. The predictions were derived through simulation from two computational models of serial recall: SIMPLE represents the class of temporal-distinctiveness models, whereas SOB-CS represents event-based models. According to temporal-distinctiveness models, items that are temporally isolated within a list are recalled more accurately than items that are temporally crowded. In contrast, event-based models assume that the time intervals between items do not affect recall performance per se, although free time following an item can improve memory for that item because of extended time for the encoding. The experimental and the simulated data were fit to an interference measurement model to measure the tendency to confuse items with other items nearby on the list-the locality constraint-in people as well as in the models. The continuous-reproduction performance showed a pronounced primacy effect with no recency, as well as some evidence for transpositions obeying the locality constraint. Though not entirely conclusive, this evidence favors event-based models over a role for temporal distinctiveness. There was also a strong detrimental effect of articulatory suppression, suggesting that verbal codes can be used to support serial-order memory of simple visual stimuli.

  2. [Results of serial CT in the evaluation of the sellar region].

    Science.gov (United States)

    Fink, U; Mayr, B; Markl, A; Baumer, K; von Werder, K; Lissner, J

    1983-12-01

    The article reports on the methodology and results of serial CT in differential diagnosis of intrasellar and parasellar structures, based on 32 examinations. Whereas the normal pituitary gland displays an approximately equal contrast medium performance as the pituitary adenomas and recurrent tumours, different types of tissue such as those of tumours, vascular structures and postoperative scans can be well differentiated from each other by means of serial CT. Aneurysms can be safely differentiated from intracranial tumours, such as meningiomas, only via serial CT.

  3. Performance enhancement of implantable medical antenna using differential feed technique

    Directory of Open Access Journals (Sweden)

    Shankar Bhattacharjee

    2016-03-01

    Full Text Available The health care industry is continuously revolutionizing and advancing towards developing more efficient system suitable for human body. Today implantable devices have become a more interesting topic in health care services which primarily started with the pacemakers. Since then it is continuously evolving due to its non-invasive nature, instant monitoring and diagnosis, and periodic simulation. The main goal of these implantable devices is to efficiently monitor or inspect various ailments in the body and then transmits this to the server or base station. For proper communication between the implant and the base station, antenna design is of prime importance. In this paper MEMS based differentially fed dual band antenna has been proposed and can be used both in Medical Implant Communication Service (MICS band for transmission of data and industrial, scientific and medical (ISM band for wake-up purpose. The proposed antenna has been simulated for free space scenario and has been found to radiate in both MICS & ISM band with S11 of −17.62 dB and −14.31 dB respectively. Subsequently the antenna is inserted within a skin mimicking model with equivalent dielectric features and the results show variation in radiation characteristics between free space condition and within skin phantom. The design of the antenna has been optimized in such a way that minimum deviation occurs between the two conformal conditions. With the use of differential feeding technique performance of the antenna is quite enhanced in terms of various parameters when compared with single feed.

  4. Independent learning modules enhance student performance and understanding of anatomy.

    Science.gov (United States)

    Serrat, Maria A; Dom, Aaron M; Buchanan, James T; Williams, Alison R; Efaw, Morgan L; Richardson, Laura L

    2014-01-01

    Didactic lessons are only one part of the multimodal teaching strategies used in gross anatomy courses today. Increased emphasis is placed on providing more opportunities for students to develop lifelong learning and critical thinking skills during medical training. In a pilot program designed to promote more engaged and independent learning in anatomy, self-study modules were introduced to supplement human gross anatomy instruction at Joan C. Edwards School of Medicine at Marshall University. Modules use three-dimensional constructs to help students understand complex anatomical regions. Resources are self-contained in portable bins and are accessible at any time. Students use modules individually or in groups in a structured self-study format that augments material presented in lecture and laboratory. Pilot outcome data, measured by feedback surveys and examination performance statistics, suggest that the activity may be improving learning in gross anatomy. Positive feedback on both pre- and post-examination surveys showed that students felt the activity helped to increase their understanding of the topic. In concordance with student perception, average examination scores on module-related laboratory and lecture questions were higher in the two years of the pilot program compared with the year before its initiation. Modules can be fabricated on a modest budget using minimal resources, making implementation practical for smaller institutions. Upper level medical students assist in module design and upkeep, enabling continuous opportunities for vertical integration across the curriculum. This resource offers a feasible mechanism for enhancing independent and lifelong learning competencies, which could be a valuable complement to any gross anatomy curriculum. © 2014 American Association of Anatomists.

  5. Genetic programming and serial processing for time series classification.

    Science.gov (United States)

    Alfaro-Cid, Eva; Sharman, Ken; Esparcia-Alcázar, Anna I

    2014-01-01

    This work describes an approach devised by the authors for time series classification. In our approach genetic programming is used in combination with a serial processing of data, where the last output is the result of the classification. The use of genetic programming for classification, although still a field where more research in needed, is not new. However, the application of genetic programming to classification tasks is normally done by considering the input data as a feature vector. That is, to the best of our knowledge, there are not examples in the genetic programming literature of approaches where the time series data are processed serially and the last output is considered as the classification result. The serial processing approach presented here fills a gap in the existing literature. This approach was tested in three different problems. Two of them are real world problems whose data were gathered for online or conference competitions. As there are published results of these two problems this gives us the chance to compare the performance of our approach against top performing methods. The serial processing of data in combination with genetic programming obtained competitive results in both competitions, showing its potential for solving time series classification problems. The main advantage of our serial processing approach is that it can easily handle very large datasets.

  6. Technical Performance of Universal and Enhanced Intraoral Imaging Rectangular Collimators

    National Research Council Canada - National Science Library

    Johnson, K Brandon; Mauriello, Sally M; Ludlow, John B; Platin, Enrique

    2015-01-01

    ...) were recruited to expose an 18 projection full mouth series (FMX) using Tru-Align™ (enhanced) and Rinn® (universal) collimator devices. Both FMXs were exposed using photostimulable phosphor...

  7. Serial Cognition and Personality in Macaques

    Directory of Open Access Journals (Sweden)

    Drew M. Altschul

    2016-02-01

    Full Text Available We examined the associations between serial cognition and personality in rhesus macaques (Macaca mulatta. Nine macaques were tested on a simultaneous chaining task to assess their cognitive abilities. They were also rated for personality traits and scored according to a previously extracted six component structure derived from free-ranging rhesus macaques. Friendliness and Openness were positively associated with good performance on three measures of accuracy on the serial learning task: Progress, Error, and Rewarded (i.e., correctly completed Trials. Faster Reaction Times were associated with lower Friendliness and higher Confidence, as well as higher Openness when only correct responses were analyzed. We also used regularized exploratory factor analysis to extract two, three, four, five, and six factor structures, and found consistent associations between accuracy and single factors within each of these structures. Prior results on intelligence in other nonhuman primate species have focused on basic intelligence tests; this study demonstrates that more complex, abstract cognitive tasks can be used to assess intelligence and personality in nonhuman primates.

  8. Serial Cognition and Personality in Macaques.

    Science.gov (United States)

    Altschul, Drew M; Terrace, Herbert S; Weiss, Alexander

    2016-02-01

    We examined the associations between serial cognition and personality in rhesus macaques (Macaca mulatta). Nine macaques were tested on a simultaneous chaining task to assess their cognitive abilities. They were also rated for personality traits and scored according to a previously extracted six component structure derived from free-ranging rhesus macaques. Friendliness and Openness were positively associated with good performance on three measures of accuracy on the serial learning task: Progress, Error, and Rewarded (i.e., correctly completed) Trials. Faster Reaction Times were associated with lower Friendliness and higher Confidence, as well as higher Openness when only correct responses were analyzed. We also used regularized exploratory factor analysis to extract two, three, four, five, and six factor structures, and found consistent associations between accuracy and single factors within each of these structures. Prior results on intelligence in other nonhuman primate species have focused on basic intelligence tests; this study demonstrates that more complex, abstract cognitive tasks can be used to assess intelligence and personality in nonhuman primates.

  9. Notorious Cases of Serial Killers

    OpenAIRE

    Iosub Elena-Cătălina

    2014-01-01

    The reconstruction of a death scene provides an overall picture of the crime and will indicate the murder as an event or one of a series of events and also the criminal. But when the criminal is declared a serial killer, many questions are raised up. How could a person kill some else without a reason or why people react in such a disorganized way and become so brutal or what made them act like that and so many questions with also so many answers. This project explains the psycholo...

  10. The effect of semantic relatedness on immediate serial recall and serial recognition.

    Science.gov (United States)

    Tse, Chi-Shing; Li, Yongna; Altarriba, Jeanette

    2011-12-01

    The present study examined the effects of semantic relatedness on immediate serial recall and serial recognition. Each participant received either blocked or randomly intermixed serial recall or serial recognition trials. Replicating the findings of previous studies (e.g., Saint-Aubin, Ouellette, & Poirier, 2005), semantic relatedness boosted percentage serial recall but also increased order errors, after taking into account the proportion of correctly recalled items, regardless of their orders, in serial recall trials. In serial recognition trials, participants' responses were slower and less accurate for related lists than for unrelated lists. There were intraindividual correlations among order memory measures in serial recall versus serial recognition trials. The implications of these findings for item redintegration theories are discussed.

  11. Sleep deprivation impairs and caffeine enhances my performance, but not always our performance: how acting in a group can change the effects of impairments and enhancements

    OpenAIRE

    Faber, Nadira S.; Häusser, Jan A.; Kerr, Norbert L.

    2015-01-01

    What effects do factors that impair or enhance performance in individuals have when these individuals act in groups? We provide a framework, called the GIE ("Effects of Grouping on Impairments and Enhancements”) framework, for investigating this question. As prominent examples for individual-level impairments and enhancements, we discuss sleep deprivation and caffeine. Based on previous research, we derive hypotheses on how they influence performance in groups, specifically process gains and ...

  12. Serial powering for the upgrades of the ATLAS pixel detector

    Energy Technology Data Exchange (ETDEWEB)

    Barbero, Marlon; Gonella, Laura; Huegging, Fabian; Krueger, Hans; Wermes, Norbert [Physikalisches Institut, Univ. Bonn, Nussallee 12, 53115 Bonn (Germany)

    2012-07-01

    A serial powering scheme is proposed for the upgrades of the ATLAS pixel detector at the High Luminosity (HL-)LHC, to provide an efficient and low material power distribution. The main regulation element is the Shunt-LDO regulator, a new regulator concept designed to meet the requirements of serially powered detector systems. The Shunt-LDO working principle was successfully demonstrated with two prototypes, and two Shunt-LDO regulators are integrated in the new ATLAS pixel FE (Front-End) chip, the FE-I4. Results of the characterization of the regulators in FE-I4 are shown, and the chip performance is compared for different powering options, with and without regulators. At the same time a serial powering demonstrator is being developed. This will include a chain of four 2-chips pixel modules, AC-coupled data transmission, dedicated HV distribution scheme, and possibly a stave protection chip. Results on the stave demonstrator are presented as well.

  13. Serial co-sputtering. Development of a versatile coating technology and its characterization using the example of rate enhancement of metal oxides by co-doping; Serielles Co-Sputtern. Entwicklung einer flexiblen Beschichtungstechnologie und deren Charakterisierung am Beispiel der Ratenerhoehung von Metalloxiden durch Co-Dotierung

    Energy Technology Data Exchange (ETDEWEB)

    Austgen, Michael

    2011-09-19

    Focus of this work is the design and characterization of a versatile coating system based on magnetron sputter deposition. This technology consists of a rotary target (primary target) that will be sputtered at one position and also can be coated at a different position with a secondary material by another sputter process. This simultaneous operation and the serial order of two sputter processes is the serial co-sputter process. A highly elaborated gas separation allows the operation of the primary sputter process in a reactive gas atmosphere whereas the secondary process can be driven in a non-reactive atmosphere. Compared to conventional co-sputtering the gas separation enables a stable operation of the secondary sputter process even if reactive gas is added to the primary sputter process. To develop an understanding of the process dynamics of serial co-sputtering the rate enhancement of metal oxides by co-doping with heavy atoms has been investigated first. If heavy elements are added to the target material the collision cascades can be reflected back towards the target surface by a more efficient momentum transfer and therefore increase the sputtering rate. The addition of heavy atoms can be achieved by serial co-sputtering. In the secondary sputter process the heavy element will be sputter deposited onto the rotary target. When entering the erosion zone of the primary sputter process the heavy atoms will be partially sputtered away and partially recoil implanted beneath the target surface. The later will contribute to the sputter yield amplification effect described above. In this work the sputter yield amplification effect has been investigated for the metal oxides Al{sub 2}O{sub 3} and TiO{sub 2} by co-doping of a aluminum and titanium rotary target with the heavy element tungsten (Z=74) and bismuth (Z=83). The primary process variables are the O{sub 2}-gas flow which determines the working point of the primary sputtering process, the rotation speed of the

  14. Reconciling rising serials costs, the serials budget, and reference needs in a medical library serials retrenchment program: a methodology.

    Science.gov (United States)

    Spang, L

    1995-01-01

    Devising a coherent serials retrenchment plan while maintaining quality reference service is a dilemma faced by increasing numbers of medical librarians. In 1991, the staff of the Shiffman Medical Library, Wayne State University, began to address increasing serials budget reductions that by 1994 amounted to a projected 20% maximum cut. The resulting retrenchment plan combined an ongoing serials use study, faculty and librarian reviews of cancellation lists, and systematic refinements in interlibrary cooperation and document delivery service. The Shiffman plan provides a constructive framework that can be adapted to other medical libraries facing immediate, major serials retrenchment.

  15. Enhancing the c-TiO2 based perovskite solar cell performance via modification by a serial of boronic acid derivative self-assembled monolayers

    Science.gov (United States)

    Kırbıyık, Çisem; Kara, Koray; Kara, Duygu Akın; Yiğit, Mesude Zeliha; İstanbullu, Bilal; Can, Mustafa; Sariciftci, Niyazi Serdar; Scharber, Markus; Kuş, Mahmut

    2017-11-01

    Morphological control of MAPbI3 crystal growth is one of the most important factor to fabricate high efficient perovskite solar cells. Herein, different boronic acid derivative self-assemble monolayers were used for modification of c-TiO2 surface and controlling of interface properties between c-TiO2 and MAPbI3 layers. Pre-mixed MAPbI3 solution in GBL was deposited by spin-coating technique onto non-modified and modified c-TiO2 surfaces by selected SAMs. The 1-OMe modified c-TiO2 based solar cell shows an increase in Jsc, resulting an increase to 9.4% PCE to compare with 5.9% PCE of non-modified c-TiO2 based solar cell. With this work, we demonstrated the possibility of morphological control of perovskite layer by using simple modification method of sublayer to increase the photovoltaic characteristics of solar cells.

  16. Pink-beam serial crystallography

    Energy Technology Data Exchange (ETDEWEB)

    Meents, A; Wiedorn, M. O.; Srajer, V.; Henning, R.; Sarrou, I.; Bergtholdt, J.; Barthelmess, M.; Reinke, P.Y.A.; Dirksmeyer, D.; Tolstikova, A.; Schaible, S.; Messerschmidt, M.; Ogata, C. M.; Kissick, D. J.; Taft, M.H.; Manstein, D.J.; Lieske, J.; Oberthuer, D.; Fischetti, R. F.; Chapman, H. N.

    2017-11-03

    Serial X-ray crystallography allows macromolecular structure determination at 31 both X-ray Free Electron Lasers (XFELs) and, more recently, synchrotron 32 sources. The time resolution for serial synchrotron crystallography experiments 33 has been limited to millisecond time scales with monochromatic beams. The 34 polychromatic, “pink”, beam provides a more than two orders of magnitude 35 increased photon flux and hence allows accessing much shorter time scales in 36 diffraction experiments at synchrotron sources. Here we report the structure 37 determination of two different protein samples by merging pink beam diffraction 38 patterns from many crystals, each collected with a single 100 ps X-ray pulse 39 exposure per crystal using a setup optimized for very low scattering background. 40 In contrast to experiments with monochromatic radiation, data from only 50 41 crystals were required to obtain complete data sets. The high quality of the 42 diffraction data highlights the potential of this method for studying irreversible 43 reactions at sub-microsecond timescales using high-brightness X-ray facilities. 44

  17. Serial MRI of limbic encephalitis

    Energy Technology Data Exchange (ETDEWEB)

    Urbach, Horst [University of Bonn Medical Center, Department of Radiology, Bonn (Germany); Soeder, Bettina M.; Bien, Christian G. [University of Bonn Medical Center, Department of Epileptology, Bonn (Germany); Jeub, Monika; Klockgether, Thomas [University of Bonn Medical Center, Department of Neurology, Bonn (Germany); Meyer, Bernhard [University of Bonn Medical Center, Department of Neurosurgery, Bonn (Germany)

    2006-06-15

    Introduction: The aim of the study was to analyze serial magnetic resonance imaging (MRI) scans in patients with various forms of limbic encephalitis (LE) in order to evaluate whether, and at what time point, MRI findings support the diagnosis of LE. Methods: Serial MRI scans (1 day to 15 years after the onset of symptoms) of 20 patients with LE were retrospectively evaluated. Of these 20 patients, 16 had definite LE (histopathological limbic inflammation, n=6; onconeural antibodies, n=5; voltage-gated potassium channel antibodies, n=3; malignant tumors, n=5), and 4 possible LE because they met the clinical criteria but had no typical antibodies or tumors. Of 13 patients who were studied with MRI within 3 months after the onset of symptoms, 11 had swollen temporomesial structures (unilateral, n=7; bilateral, n=4). After up to 9 months, the swelling had resolved in nine of ten re-evaluated patients. Of seven patients who were initially studied with MRI more than 3 months after disease onset, three had swollen temporomesial structures, one had a hyperintense, normal-sized hippocampus, and three had hyperintense and atrophic temporomesial structures. LE starts as an acute disease with uni- or bilateral swollen temporomesial structures that are hyperintense on fluid attenuation inversion recovery and T2-weighted sequences. Swelling and hyperintensity may persist over months to years, but in most cases progressive temporomesial atrophy develops. (orig.)

  18. Wavelength Preserving Optical Serial-to-Parallel Conversion

    DEFF Research Database (Denmark)

    Galili, Michael; Palushani, Evarist; Mulvad, Hans Christian Hansen

    2013-01-01

    We demonstrate optical wavelength preserving serial-to-parallel conversion. 9-of-16 OTDM channels are simultaneously mapped from a 160 Gbit/s signal to a 100 GHz WDM grid by wavelength preserving FWM idler generation, with BER<1E-9 performance....

  19. Phonological Similarity in Serial Recall: Constraints on Theories of Memory

    Science.gov (United States)

    Lewandowsky, Stephan; Farrell, Simon

    2008-01-01

    In short-term serial recall, similar-sounding items are remembered more poorly than items that do not sound alike. When lists mix similar and dissimilar items, performance on the dissimilar items is of considerable theoretical interest. Farrell and Lewandowsky [Farrell, S., & Lewandowsky, S. (2003). Dissimilar items benefit from phonological…

  20. Serial Entrepreneurship, Learning by Doing and Self-selection

    DEFF Research Database (Denmark)

    Rocha, Vera; Carneiro, Anabela; Varum, Celeste

    2015-01-01

    It remains a question whether serial entrepreneurs typically perform better than their novice counterparts owing to learning by doing effects or mostly because they are a selected sample of higher-than-average ability entrepreneurs. This paper tries to unravel these two effects by exploring a nov...

  1. Performance of taste enhancers mixed with cereal bases and ...

    African Journals Online (AJOL)

    Baiting technique if appropriately applied is the most reliable strategy to control rodent pests. Behavior modifying components may play a significant role in developing the most attractive baits. An attempt was therefore made to investigate the behavior revolutionizing effect of taste enhancers including peanut oil, peanut ...

  2. An Enhancement of Visual Test Performance for Nuclear Fuel Assembly

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Jai Wan; Choi, Young Soo [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Shin, Jung Cheol [Korea Nuclear Fuel, Daejeon (Korea, Republic of)

    2009-05-15

    system) will have a measurable visual acuity. The visual acuity parameter describes what a system can detect and discern. Current underwater radiation-hardened video camera, which is composed of tube- type vidicon image sensor, used in the VT of fuel assembly has not sufficient resolution regardless of high cost. As the resolution of the COTS SOTA (state-of-theart) CCD image sensor is higher than the tube-type image sensor, the VT of the fuel assembly clearly meets the EPRI VT-1 guideline, if assumed that the radiation-weakened SOTA CCD camera is properly shielded from the high dose rate gamma-ray source. In this paper, it is described that a radiation-tolerant camera system, which are composed of COTS SOTA CCD camera, zoom lens, anti-reflection mirror, and visible window, meets the EPRI VT-1 guideline for the VT of the nuclear fuel assembly. Generally, the VT of the four face of nuclear fuel assembly, which is a high dose-rate gamma source, is performed in the underwater canal. The width of canal, d{sub 1}, is about 1,500mm. As the distance, d{sub 2}, between the fuel assembly (d{sub 3}, 224mm) and the camera system, assumed that the width of camera system is about 200mm, is short below one-tenth shielding thickness of gamma-ray of water, about 660mm, a COTS SOTA CCD camera cannot be used directly. As shown in Fig. 1 and Table 1, the observation distance between the fuel assembly and the CCD camera, is 438{approx}588mm. These observation distances are shorter than the MOD (minimum object distance) of the SOTA CCD cameras (Sony FCB-PV480 and FCB-H10). The MOD of these SOTA color CCD camera are 800mm and 1,000mm. In this paper, in order to enhance the optimum observation performance, the close-up lens (No. 2) was used. An observation distance of 400mm from the test samples was acquired.

  3. Effects of glucose on the performance of enhanced biological phosphorus removal activated sludge enriched with acetate.

    Science.gov (United States)

    Gebremariam, Seyoum Yami; Beutel, Marc W; Christian, David; Hess, Thomas F

    2012-10-01

    The effects of glucose on enhanced biological phosphorus removal (EBPR) activated sludge enriched with acetate was investigated using sequencing batch reactors. A glucose/acetate mixture was serially added to the test reactor in ratios of 25/75%, 50/50%, and 75/25% and the EBPR activity was compared to the control reactor fed with 100% acetate. P removal increased at a statistically significant level to a near-complete in the test reactor when the mixture increased to 50/50%. However, EBPR deteriorated when the glucose/acetate mixture increased to 75/25% in the test reactor and when the control reactor abruptly switched to 100% glucose. These results, in contrast to the EBPR conventional wisdom, suggest that the addition of glucose at moderate levels in wastewaters does not impede and may enhance EBPR, and that glucose waste products should be explored as an economical sustainable alternative when COD enhancement of EBPR is needed. Copyright © 2012 Elsevier Ltd. All rights reserved.

  4. Visual and Phonological Similarity Effects in Verbal Immediate Serial Recall: A Test with Kanji Materials

    Science.gov (United States)

    Saito, Satoru; Logie, Robert H.; Morita, Aiko; Law, Anna

    2008-01-01

    In a series of three experiments, native speakers of Japanese performed serial ordered written recall of visually presented Japanese kanji characters that varied systematically in visual and phonological similarity. Overall effects of phonological similarity were observed for retention of serial order under silent reading in Experiments 1 and 3…

  5. The Relationship Context of Premarital Serial Cohabitation.

    Science.gov (United States)

    Cohen, Jessica; Manning, Wendy

    2010-09-01

    Even though serial cohabitation is on the rise, it has not been integrated into recent family research. We analyze the National Survey of Family Growth (NSFG) cycle 6 to explore the relationship context of serial cohabitation for women throughout emerging adulthood (N=3,397). We provide a relationship context for serial cohabitation by examining the age at first cohabitation, duration of cohabiting unions, marital expectations and transitions, as well as premarital sexual histories. Furthermore, we examine the change in these relationship indicators across women's birth cohorts. We find that serial cohabitors' co-residential unions are about the same duration as single-instance cohabiting unions. Serial cohabitors start cohabiting younger, report lower marital expectations than single-instance cohabitors and a smaller proportion marry before age 30. Women who have more premarital sex partners have significantly greater odds of serial cohabiting. These findings indicate that women face increasingly complex relationship trajectories during emerging adulthood.

  6. Performance Enhancing Diets and the PRISE Protocol to Optimize Athletic Performance

    Directory of Open Access Journals (Sweden)

    Paul J. Arciero

    2015-01-01

    Full Text Available The training regimens of modern-day athletes have evolved from the sole emphasis on a single fitness component (e.g., endurance athlete or resistance/strength athlete to an integrative, multimode approach encompassing all four of the major fitness components: resistance (R, interval sprints (I, stretching (S, and endurance (E training. Athletes rarely, if ever, focus their training on only one mode of exercise but instead routinely engage in a multimode training program. In addition, timed-daily protein (P intake has become a hallmark for all athletes. Recent studies, including from our laboratory, have validated the effectiveness of this multimode paradigm (RISE and protein-feeding regimen, which we have collectively termed PRISE. Unfortunately, sports nutrition recommendations and guidelines have lagged behind the PRISE integrative nutrition and training model and therefore limit an athletes’ ability to succeed. Thus, it is the purpose of this review to provide a clearly defined roadmap linking specific performance enhancing diets (PEDs with each PRISE component to facilitate optimal nourishment and ultimately optimal athletic performance.

  7. Serial binary interval ratios improve rhythm reproduction

    Directory of Open Access Journals (Sweden)

    Xiang eWu

    2013-08-01

    Full Text Available Musical rhythm perception is a natural human ability that involves complex cognitive processes. Rhythm refers to the organization of events in time, and musical rhythms have an underlying hierarchical metrical structure. The metrical structure induces the feeling of a beat and the extent to which a rhythm induces the feeling of a beat is referred to as its metrical strength. Binary ratios are the most frequent interval ratio in musical rhythms. Rhythms with hierarchical binary ratios are better discriminated and reproduced than rhythms with hierarchical non-binary ratios. However, it remains unclear whether a superiority of serial binary over non-binary ratios in rhythm perception and reproduction exists. In addition, how different types of serial ratios influence the metrical strength of rhythms remains to be elucidated. The present study investigated serial binary vs. non-binary ratios in a reproduction task. Rhythms formed with exclusively binary (1:2:4:8, non-binary integer (1:3:5:6, and non-integer (1:2.3:5.3:6.4 ratios were examined within a constant meter. The results showed that the 1:2:4:8 rhythm type was more accurately reproduced than the 1:3:5:6 and 1:2.3:5.3:6.4 rhythm types, and the 1:2.3:5.3:6.4 rhythm type was more accurately reproduced than the 1:3:5:6 rhythm type. Further analyses showed that reproduction performance was better predicted by the distribution pattern of event occurrences within an inter-beat interval, than by the coincidence of events with beats, or the magnitude and complexity of interval ratios. Whereas rhythm theories and empirical data emphasize the role of the coincidence of events with beats in determining metrical strength and predicting rhythm performance, the present results suggest that rhythm processing may be better understood when the distribution pattern of event occurrences is taken into account. These results provide new insights into the mechanisms underlining musical rhythm perception.

  8. Serial binary interval ratios improve rhythm reproduction.

    Science.gov (United States)

    Wu, Xiang; Westanmo, Anders; Zhou, Liang; Pan, Junhao

    2013-01-01

    Musical rhythm perception is a natural human ability that involves complex cognitive processes. Rhythm refers to the organization of events in time, and musical rhythms have an underlying hierarchical metrical structure. The metrical structure induces the feeling of a beat and the extent to which a rhythm induces the feeling of a beat is referred to as its metrical strength. Binary ratios are the most frequent interval ratio in musical rhythms. Rhythms with hierarchical binary ratios are better discriminated and reproduced than rhythms with hierarchical non-binary ratios. However, it remains unclear whether a superiority of serial binary over non-binary ratios in rhythm perception and reproduction exists. In addition, how different types of serial ratios influence the metrical strength of rhythms remains to be elucidated. The present study investigated serial binary vs. non-binary ratios in a reproduction task. Rhythms formed with exclusively binary (1:2:4:8), non-binary integer (1:3:5:6), and non-integer (1:2.3:5.3:6.4) ratios were examined within a constant meter. The results showed that the 1:2:4:8 rhythm type was more accurately reproduced than the 1:3:5:6 and 1:2.3:5.3:6.4 rhythm types, and the 1:2.3:5.3:6.4 rhythm type was more accurately reproduced than the 1:3:5:6 rhythm type. Further analyses showed that reproduction performance was better predicted by the distribution pattern of event occurrences within an inter-beat interval, than by the coincidence of events with beats, or the magnitude and complexity of interval ratios. Whereas rhythm theories and empirical data emphasize the role of the coincidence of events with beats in determining metrical strength and predicting rhythm performance, the present results suggest that rhythm processing may be better understood when the distribution pattern of event occurrences is taken into account. These results provide new insights into the mechanisms underlining musical rhythm perception.

  9. Technical Performance of Universal and Enhanced Intraoral Imaging Rectangular Collimators.

    Science.gov (United States)

    Johnson, K Brandon; Mauriello, Sally M; Ludlow, John B; Platin, Enrique

    2015-08-01

    The purpose of this study was to compare the number and type of technical errors between 2 rectangular collimators, time/motion effort and radiographer preference. Subjects (n=17) were recruited to expose an 18 projection full mouth series (FMX) using Tru-Align™ (enhanced) and Rinn® (universal) collimator devices. Both FMXs were exposed using photostimulable phosphor (PSP) digital sensors on a DXTTR manikin with an intraoral x-ray unit. A 5-question survey evaluated ease of device use, time required and device preference. Data were analyzed using frequencies, paired t-test, ANOVA and least squares means using a general linear model. A lower mean number of technique errors per FMX occurred with the enhanced device (9.7) compared to the universal device (12.1). Collimator centering errors occurred 3-times more often with the universal device. The mean numbers of diagnostically unacceptable errors per FMX were similar (Universal=3.2 vs Enhanced=2.9). The least squares means adjusted model showed a statistically significant difference of errors between the 2 devices (p=0.0478) and errors by location when comparing posterior to anterior and posterior to bitewing (pradiographs more efficiently with fewer collimator centering errors; however, it does so with a 35% greater exposure area and a concomitant increase in patient dose. Copyright © 2015 The American Dental Hygienists’ Association.

  10. Save the last dance for me: unwanted serial position effects in jury evaluations.

    Science.gov (United States)

    Bruine de Bruin, Wändi

    2005-03-01

    Whenever competing options are considered in sequence, their evaluations may be affected by order of appearance. Such serial position effects would threaten the fairness of competitions using jury evaluations. Randomization cannot reduce potential order effects, but it does give candidates an equal chance of being assigned to preferred serial positions. Whether, or what, serial position effects emerge may depend on the cognitive demands of the judgment task. In end-of-sequence procedures, final scores are not given until all candidates have performed, possibly burdening judges' memory. If judges' evaluations are based on how well they remember performances, serial position effects may resemble those found with free recall. Candidates may also be evaluated step-by-step, immediately after each performance. This procedure should not burden memory, though it may produce different serial position effects. Yet, this paper reports similar serial position effects with end-of-sequence and step-by-step procedures used for the Eurovision Song Contest: Ratings increased with serial position. The linear order effect was replicated in the step-by-step judgments of World and European Figure Skating Contests. It is proposed that, independent of the evaluation procedure, judges' initial impressions of sequentially appearing candidates may be formed step-by-step, yielding serial position effects.

  11. Robot Control for Task Performance and Enhanced Safety under Impact

    Directory of Open Access Journals (Sweden)

    Yiannis eKarayiannidis

    2015-12-01

    Full Text Available A control law combining motion performance quality and low stiffness reaction to unintended contacts is proposed in this work. It achieves prescribed performance evolution of the position error under disturbances up to a level related to model uncertainties and responds compliantly and with low stiffness to significant disturbances arising from impact forces. The controller employs a velocity reference signal in a model-based control law utilizing a nonlinear time-dependent term which embeds prescribed performance specifications and vanishes in case of significant disturbances. Simulation results with a three degrees of freedom (DOF robot illustrate the motion performance and self-regulation of the output stiffness achieved by this controller under an external force, and highlights its advantages with respect to constant and switched impedance schemes. Experiments with a KUKA LWR4+ demonstrate its performance under impact with a human while following a desired trajectory.

  12. Enhancing Surgical Team Performance with Game-Based training

    Directory of Open Access Journals (Sweden)

    Christine Kreutzer

    2016-03-01

    Full Text Available  Poor team communication has been attributed to many patient safety issues in healthcare. Efficacious team training methods are needed. The present study examines the use of a game-based training approach for enhancing surgical team communication skills. Participants who played the game achieved improved declarative knowledge, and had greater levels of training transfer relative to the control group. These results suggest that game-based training may to be a promising mechanism for improving teamwork in the healthcare industry.  

  13. Enhanced thermoelectric performance and anomalous seebeck effects in topological insulators.

    Science.gov (United States)

    Xu, Yong; Gan, Zhongxue; Zhang, Shou-Cheng

    2014-06-06

    Improving the thermoelectric figure of merit zT is one of the greatest challenges in material science. The recent discovery of topological insulators (TIs) offers new promise in this prospect. In this work, we demonstrate theoretically that zT is strongly size dependent in TIs, and the size parameter can be tuned to enhance zT to be significantly greater than 1. Furthermore, we show that the lifetime of the edge states in TIs is strongly energy dependent, leading to large and anomalous Seebeck effects with an opposite sign to the Hall effect. These striking properties make TIs a promising material for thermoelectric science and technology.

  14. Performance-Enhancing Drugs in Sport: A Different Form of Drug Abuse.

    Science.gov (United States)

    Fuller, John R.; LaFountain, Marc J.

    1987-01-01

    Addresses an often overlooked area of drug abuse: performance-enhancing drugs in sport, used for different reasons than for recreation. Examines the seriousness and prevalence of performance-enhancing drugs and presents the results of a series of interviews with steroid users to determine their attitudes. Discusses the implications of the…

  15. The dynamics of shared leadership: building trust and enhancing performance.

    Science.gov (United States)

    Drescher, Marcus A; Korsgaard, M Audrey; Welpe, Isabell M; Picot, Arnold; Wigand, Rolf T

    2014-09-01

    In this study, we examined how the dynamics of shared leadership are related to group performance. We propose that, over time, the expansion of shared leadership within groups is related to growth in group trust. In turn, growth in group trust is related to performance improvement. Longitudinal data from 142 groups engaged in a strategic simulation game over a 4-month period provide support for positive changes in trust mediating the relationship between positive changes in shared leadership and positive changes in performance. Our findings contribute to the literature on shared leadership and group dynamics by demonstrating how the growth in shared leadership contributes to the emergence of trust and a positive performance trend over time. PsycINFO Database Record (c) 2014 APA, all rights reserved.

  16. Enhanced Performance of Recycled Aggregate Concrete with Atomic Polymer Technology

    Science.gov (United States)

    2012-06-01

    The atomic polymer technology in form of mesoporous inorganic polymer (MIP) can effectively improve material durability and performance of concrete by dramatically increase inter/intragranular bond strength of concrete at nano-scale. The strategy of ...

  17. Enhancing first- year mathematics performance at the University of ...

    African Journals Online (AJOL)

    Higher education, teaching and learning, first-year student experience, mathematics performance, ..... Paper presented at Creating Spaces: Interdisciplinary Writings in the Social Sciences ... Arts and Humanities in Education, 8(3), 339–354.

  18. POLICIES AND STRATEGIES FOR ENHANCING THE PERFORMANCE OF CORPORATE

    Directory of Open Access Journals (Sweden)

    DAN ROXANA LOREDANA

    2015-08-01

    Full Text Available In the paper below, starting with the main models and theories of literature dealing with the subject of corporate governance, we propose to identify and bring to your attention how these theories are most suitable for improving the performance of the company. In this regard, focusing on the stakeholder objectives, we want to emphasize which are the most relevant policies and strategies for the argumentation of corporate governance performance.

  19. Enhanced performance of dicationic ionic liquid electrolytes by organic solvents.

    Science.gov (United States)

    Li, Song; Zhang, Pengfei; Fulvio Pasquale, F; Hillesheim Patrick, C; Feng, Guang; Dai, Sheng; Cummings Peter, T

    2014-07-16

    The use of dicationic ionic liquid (DIL) electrolytes in supercapacitors is impeded by the slow dynamics of DILs, whereas the addition of organic solvents into DIL electrolytes improves ion transport and then enhances the power density of supercapacitors. In this work, the influences of organic solvents on the conductivity of DILs and the electrical double layer (EDL) of DIL-based supercapacitors are investigated using classical molecular dynamics simulation. Two types of organic solvents, acetonitrile (ACN) and propylene carbonate (PC), were used to explore the effects of different organic solvents on the EDL structure and capacitance of DIL/organic solvent-based supercapacitors. Firstly, it was found that the conductivity of DIL electrolytes was greatly enhanced in the presence of the organic solvent ACN. Secondly, a stronger adsorption of PC on graphite results in different EDL structures formed by DIL/ACN and DIL/PC electrolytes. The expulsion of co-ions from EDLs was observed in DIL/organic solvent electrolytes rather than neat DILs and this feature is more evident in DIL/PC. Furthermore, the bell-shaped differential capacitance-electric potential curve was not essentially changed by the presence of organic solvents. Comparing DIL/organic solvent electrolytes with neat DILs, the capacitance is slightly increased by organic solvents, which is in agreement with experimental observation.

  20. Enhancing Team Performance for Long-Duration Space Missions

    Science.gov (United States)

    Orasanu, Judith M.

    2009-01-01

    Success of exploration missions will depend on skilled performance by a distributed team that includes both the astronauts in space and Mission Control personnel. Coordinated and collaborative teamwork will be required to cope with challenging complex problems in a hostile environment. While thorough preflight training and procedures will equip creW'S to address technical problems that can be anticipated, preparing them to solve novel problems is much more challenging. This presentation will review components of effective team performance, challenges to effective teamwork, and strategies for ensuring effective team performance. Teamwork skills essential for successful team performance include the behaviors involved in developing shared mental models, team situation awareness, collaborative decision making, adaptive coordination behaviors, effective team communication, and team cohesion. Challenges to teamwork include both chronic and acute stressors. Chronic stressors are associated with the isolated and confined environment and include monotony, noise, temperatures, weightlessness, poor sleep and circadian disruptions. Acute stressors include high workload, time pressure, imminent danger, and specific task-related stressors. Of particular concern are social and organizational stressors that can disrupt individual resilience and effective mission performance. Effective team performance can be developed by training teamwork skills, techniques for coping with team conflict, intracrew and intercrew communication, and working in a multicultural team; leadership and teamwork skills can be fostered through outdoor survival training exercises. The presentation will conclude with an evaluation of the special requirements associated with preparing crews to function autonomously in long-duration missions.

  1. Semantic contribution to verbal short-term memory: are pleasant words easier to remember than neutral words in serial recall and serial recognition?

    Science.gov (United States)

    Monnier, Catherine; Syssau, Arielle

    2008-01-01

    In the four experiments reported here, we examined the role of word pleasantness on immediate serial recall and immediate serial recognition. In Experiment 1, we compared verbal serial recall of pleasant and neutral words, using a limited set of items. In Experiment 2, we replicated Experiment 1 with an open set of words (i.e., new items were used on every trial). In Experiments 3 and 4, we assessed immediate serial recognition of pleasant and neutral words, using item sets from Experiments 1 and 2. Pleasantness was found to have a facilitation effect on both immediate serial recall and immediate serial recognition. This study supplies some new supporting arguments in favor of a semantic contribution to verbal short-term memory performance. The pleasantness effect observed in immediate serial recognition showed that, contrary to a number of earlier findings, performance on this task can also turn out to be dependent on semantic factors. The results are discussed in relation to nonlinguistic and psycholinguistic models of short-term memory.

  2. Judgments about illegal performance-enhancing substances: reasoned, reactive, or both?

    Science.gov (United States)

    Dodge, Tonya; Stock, Michelle; Litt, Dana

    2013-07-01

    This study applied aspects of the Theory of Reasoned Action and the Prototype/Willingness model to understand cognitions associated with the use of illegal performance-enhancing substances. There were two study objectives. One was to investigate whether the illegal-is-effective heuristic (i.e. belief that illegal performance-enhancing substances are more effective than legal performance-enhancing substances) affects willingness to use illegal performance-enhancing substances. The second was to examine whether attitudes, norms, and prototypes influence the willingness and intentions to use illegal performance-enhancing substances. The illegal-is-effective heuristic was a significant predictor of willingness but was not a significant predictor of intentions. Implications for future research and prevention efforts are discussed.

  3. Task based synthesis of serial manipulators

    Directory of Open Access Journals (Sweden)

    Sarosh Patel

    2015-05-01

    Full Text Available Computing the optimal geometric structure of manipulators is one of the most intricate problems in contemporary robot kinematics. Robotic manipulators are designed and built to perform certain predetermined tasks. There is a very close relationship between the structure of the manipulator and its kinematic performance. It is therefore important to incorporate such task requirements during the design and synthesis of the robotic manipulators. Such task requirements and performance constraints can be specified in terms of the required end-effector positions, orientations and velocities along the task trajectory. In this work, we present a comprehensive method to develop the optimal geometric structure (DH parameters of a non-redundant six degree of freedom serial manipulator from task descriptions. In this work we define, develop and test a methodology to design optimal manipulator configurations based on task descriptions. This methodology is devised to investigate all possible manipulator configurations that can satisfy the task performance requirements under imposed joint constraints. Out of all the possible structures, the structures that can reach all the task points with the required orientations are selected. Next, these candidate structures are tested to see whether they can attain end-effector velocities in arbitrary directions within the user defined joint constraints, so that they can deliver the best kinematic performance. Additionally least power consuming configurations are also identified.

  4. Serial Assessment of Therapeutic Response to a New Radiosensitization Treatment, Kochi Oxydol-Radiation Therapy for Unresectable Carcinomas, Type II (KORTUC II, in Patients with Stage I/II Breast Cancer Using Breast Contrast-Enhanced Magnetic Resonance Imaging

    Directory of Open Access Journals (Sweden)

    Shin Yaogawa

    2015-12-01

    Full Text Available Background: We have developed a new radiosensitization treatment called Kochi Oxydol-Radiation Therapy for Unresectable Carcinomas, Type II (KORTUC II. Using KORTUC II, we performed breast-conserving treatment (BCT without any surgical procedure for elderly patients with breast cancer in stages I/II or patients refusing surgery. Since surgery was not performed, histological confirmation of the primary tumor region following KORTUC II treatment was not possible. Therefore, to precisely evaluate the response to this new therapy, a detailed diagnostic procedure is needed. The goal of this study was to evaluate the therapeutic response to KORTUC II treatment in patients with stage I/II breast cancer using annual breast contrast-enhanced (CE magnetic resonance imaging (MRI. Methods: Twenty-one patients with stage I/II breast cancer who were elderly and/or refused surgery were enrolled in this study. All patients underwent MRI prior to and at 3 to 6 months after KORTUC II, and then approximately biannually thereafter. Findings from MRI were compared with those from other diagnostic modalities performed during the same time period. Results: KORTUC II was well tolerated, with minimal adverse effects. All of 21 patients showed a clinically complete response (cCR on CE MRI. The mean period taken to confirm cCR on the breast CE MRI was approximately 14 months. The mean follow-up period for the patients was 61.9 months at the end of October 2014. Conclusions: The therapeutic effect of BCT using KORTUC II without surgery could be evaluated by biannual CE MRI evaluations. Approximately 14 months were required to achieve cCR in response to this therapy.

  5. Enhanced visual performance in obsessive compulsive personality disorder.

    Science.gov (United States)

    Ansari, Zohreh; Fadardi, Javad Salehi

    2016-12-01

    Visual performance is considered as commanding modality in human perception. We tested whether Obsessive-compulsive personality disorder (OCPD) people do differently in visual performance tasks than people without OCPD. One hundred ten students of Ferdowsi University of Mashhad and non-student participants were tested by Structured Clinical Interview for DSM-IV Axis II Personality Disorders (SCID-II), among whom 18 (mean age = 29.55; SD = 5.26; 84% female) met the criteria for OCPD classification; controls were 20 persons (mean age = 27.85; SD = 5.26; female = 84%), who did not met the OCPD criteria. Both groups were tested on a modified Flicker task for two dimensions of visual performance (i.e., visual acuity: detecting the location of change, complexity, and size; and visual contrast sensitivity). The OCPD group had responded more accurately on pairs related to size, complexity, and contrast, but spent more time to detect a change on pairs related to complexity and contrast. The OCPD individuals seem to have more accurate visual performance than non-OCPD controls. The findings support the relationship between personality characteristics and visual performance within the framework of top-down processing model. © 2016 Scandinavian Psychological Associations and John Wiley & Sons Ltd.

  6. Enhanced DLC wear performance by the presence of lubricant additives

    Directory of Open Access Journals (Sweden)

    Romina Paula de Castro Costa

    2011-01-01

    Full Text Available Lubricant additives play significant role for reducing friction and wear of mechanical elements. The additives presented in 5W30 oil were developed for metal surfaces. However, they have been used in engine pieces covered with DLC coatings because they also offer the potential to reduce friction losses and wear in automotive applications. The friction and wear tests were carried out by using a UMT-CETR ball-on-disk tribometer in rotational mode under 5W30 synthetic oil at 100 °C. The X-ray photoelectron spectroscopy (XPS showed the presence of Mo and S in the wear tracks. These elements are from decomposition of ZDDP and MoDTC additives producing MoS2 in DLC surface, which offers enhanced durability by low wear rate.

  7. Enhanced thermoelectric performance of amorphous Nb based oxynitrides

    Energy Technology Data Exchange (ETDEWEB)

    Music, Denis, E-mail: music@mch.rwth-aachen.de; Geyer, Richard W.; Hans, Marcus

    2015-12-15

    Using density functional theory, amorphous Nb{sub 0.27}Ru{sub 0.06}O{sub 0.56}N{sub 0.10} was designed to facilitate a combination of an enhanced Seebeck coefficient and low electrical resistivity. Based on a positive Cauchy pressure, ductile behavior is expected. To verify these predictions, the transport and mechanical properties of amorphous thin films were evaluated. Metallic electrical resistivity and the Seebeck coefficient of −94 µV K{sup −1} are obtained, which is consistent with our predictions. As there is no crack formation, these samples can be perceived as ductile. We demonstrate that the power factor can be increased by an order of magnitude, while keeping the thermal fatigue low.

  8. COMMUNICATION OPENNESS IN PERFORMANCE APPRAISAL SYSTEMS ENHANCING JOB SATISFACTION

    Directory of Open Access Journals (Sweden)

    ISMAIL Azman

    2014-06-01

    Full Text Available The aim of this paper is to investigate the relationship between communication openness in performance appraisal systems and job satisfaction. A survey method was employed to gather data from employees who have worked in a privatized postal company in Sarawak, Malaysia. SmartPLS version 2.0 was used to determine the validity and reliability of instrument and test the research hypotheses. The outcomes of SmartPLS path model showed that explanation and feedback were positively and significantly related to job satisfaction. This result confirms that the ability of appraisers to clearly explain the performance appraisal practices and adequately provide feedback in determining performance scores have been important predictors of appraises’ job satisfaction in the studied organization. Further, this study provides discussion, implications and conclusion.

  9. Performance Enhancement of Unsteady Ejectors Investigated Using a Pulsejet Driver

    Science.gov (United States)

    Paxson, Daniel E.

    2003-01-01

    Unsteady ejectors are currently under investigation for use in some pulse detonation engine (PDE) propulsion systems. This is due primarily to their potential high performance in comparison to steady ejectors of similar dimensions relative to the source or driver jet. Although some experimental work has been done in the past to study thrust augmentation with unsteady ejectors, there is no proven theory by which optimal design parameters can be selected and an effective ejector constructed for a given pulsed flow. Therefore, an experimental facility was developed at the NASA Glenn Research Center to study the correlation between ejector design and performance, and to get a better understanding of the flow phenomena that result in thrust augmentation. A commercially available pulsejet was used for the unsteady driving jet. This was paired with a basic, yet flexible, ejector design that allowed parametric evaluation of the effects that length, diameter, and inlet radius have on performance.

  10. Serial Position Functions in General Knowledge

    Science.gov (United States)

    Kelley, Matthew R.; Neath, Ian; Surprenant, Aimée M.

    2015-01-01

    Serial position functions with marked primacy and recency effects are ubiquitous in episodic memory tasks. The demonstrations reported here explored whether bow-shaped serial position functions would be observed when people ordered exemplars from various categories along a specified dimension. The categories and dimensions were: actors and age;…

  11. Female serial killing: review and case report.

    Science.gov (United States)

    Frei, Andreas; Völlm, Birgit; Graf, Marc; Dittmann, Volker

    2006-01-01

    Single homicide committed by women is rare. Serial killing is very infrequent, and the perpetrators are usually white, intelligent males with sadistic tendencies. Serial killing by women has, however, also been described. To conduct a review of published literature on female serial killers and consider its usefulness in assessing a presenting case. A literature review was conducted, after searching EMBASE, MEDLINE and PsycINFO. The presenting clinical case is described in detail in the context of the literature findings. Results The literature search revealed few relevant publications. Attempts to categorize the phenomenon of female serial killing according to patterns of and motives for the homicides have been made by some authors. The most common motive identified was material gain or similar extrinsic gratification while the 'hedonistic' sadistic or sexual serial killer seems to be extremely rare in women. There is no consistent theory of serial killing by women, but psychopathic personality traits and abusive childhood experiences have consistently been observed. The authors' case did not fit the description of a 'typical' female serial killer. In such unusual circumstances as serial killing by a woman, detailed individual case formulation is required to make sense of the psychopathology in each case. Publication of cases in scientific journals should be encouraged to advance our understanding of this phenomenon. Copyright (c) 2006 John Wiley & Sons, Ltd.

  12. The Serial Murderer's Motivations: An Interdisciplinary Review.

    Science.gov (United States)

    DeHart, Dana D.; Mahoney, John M.

    1994-01-01

    Defines serial killer as individual who murders two or more victims over an extended period of time, ranging from days to years, with the crimes often being sexually motivated. Reviews existing motivational theories of serial murder and proposes additional explications from range of disciplines. Presents suggestions for future research and…

  13. Modus operandi of female serial killers.

    Science.gov (United States)

    Wilson, W; Hilton, T

    1998-04-01

    The modus operandi of female serial killers was examined from a chronology of 58 cases in America and 47 cases in 17 other countries, compiled over 25-year intervals. Female serial killers in other countries accounted for a disproportionately greater number of victims, but those in America managed a longer killing career when associated with a low profile modus operandi.

  14. Organic acids for performance enhancement in pig diets

    NARCIS (Netherlands)

    Partanen, K.H.; Mroz, Z.

    1999-01-01

    Organic acids and their salts appear to be potential alternatives to prophylactic in-feed antibiotics and growth promoters in order to improve the performance of weaned piglets, fattening pigs and reproductive sows, although their growth-promoting effects are generally less than that of antibiotics.

  15. Performance enhancement of a pump impeller using optimal design method

    Science.gov (United States)

    Jeon, Seok-Yun; Kim, Chul-Kyu; Lee, Sang-Moon; Yoon, Joon-Yong; Jang, Choon-Man

    2017-04-01

    This paper presents the performance evaluation of a regenerative pump to increase its efficiency using optimal design method. Two design parameters which define the shape of the pump impeller, are introduced and analyzed. Pump performance is evaluated by numerical simulation and design of experiments(DOE). To analyze three-dimensional flow field in the pump, general analysis code, CFX, is used in the present work. Shear stress turbulence model is employed to estimate the eddy viscosity. Experimental apparatus with an open-loop facility is set up for measuring the pump performance. Pump performance, efficiency and pressure, obtained from numerical simulation are validated by comparison with the results of experiments. Throughout the shape optimization of the pump impeller at the operating flow condition, the pump efficiency is successfully increased by 3 percent compared to the reference pump. It is noted that the pressure increase of the optimum pump is mainly caused by higher momentum force generated inside blade passage due to the optimal blade shape. Comparisons of pump internal flow on the reference and optimum pump are also investigated and discussed in detail.

  16. Compressive sensing for high resolution profiles with enhanced Doppler performance

    NARCIS (Netherlands)

    Anitori, L.; Hoogeboom, P.; Chevalier, F. Le; Otten, M.P.G.

    2012-01-01

    In this paper we demonstrate how Compressive Sensing (CS) can be used in pulse-Doppler radars to improve the Doppler performance while preserving range resolution. We investigate here two types of stepped frequency waveforms, the coherent frequency bursts and successive frequency ramps, which can be

  17. Downsizing?-?Intellectual Capital Performance Anorexia or Enhancement?

    Science.gov (United States)

    Williams, S. Mitchell

    2004-01-01

    The objective of this paper is to investigate if downsizing contributes to, or impedes, a firm's intellectual capital performance (ICE) based on a longitudinal analysis of 56 United States publicly listed companies that significantly downsized their workforce during the mid-1990s. Empirical analysis indicates that for the majority of firms, ICE…

  18. Performance Assessment of Communication Enhancement Devices TEA HI Threat Headset

    Science.gov (United States)

    2015-08-01

    for Science and Education Oak Ridge, TN Billy J. Swayne Ball Aerospace Technologies Dayton, OH August 2015 Interim Report Distribution A...Force Research Laboratory Education 711 Human Performance Wing Oak Ridge, TN 37831 Human Effectiveness Directorate...much protection a hearing protection device (HPD) provided in an environment where the ambient noise levels were fairly stable (for example, riding in

  19. Enhancing Performance & Preventing Injuries in Team Sport Players

    NARCIS (Netherlands)

    van der Does, Hendrike

    2016-01-01

    Next to physical load and recovery as a result of training, psychosocial stress and recovery affect performance and injury risk of team sport players. This can be concluded based on a series of studies that focus on the relation between jumping technique, training load, training recovery,

  20. Thermo-hydraulic performance enhancement of solar air heater ...

    African Journals Online (AJOL)

    The present paper studies the thermal performance of solar air heater which is artificially roughened by providing multiple arcs with gap shaped roughness element. As thermal efficiency of smooth collector is quite low, hence there is a need to augment heat transfer from the absorbing surface. The experimentation has ...

  1. Thermo-hydraulic performance enhancement of solar air heater ...

    African Journals Online (AJOL)

    DR OKE

    The present paper studies the thermal performance of solar air heater which is artificially roughened by providing multiple arcs with gap shaped ... Keywords: Solar air heater; Nusselt number; thermal efficiency; multiple arcs with gap; roughened .... The glass wool was used as insulation inside wooden panel to reduce.

  2. Design methodology to enhance high impedance surfaces performances

    Directory of Open Access Journals (Sweden)

    M. Grelier

    2014-04-01

    Full Text Available A methodology is introduced for designing wideband, compact and ultra-thin high impedance surfaces (HIS. A parametric study is carried out to examine the effect of the periodicity on the electromagnetic properties of an HIS. This approach allows designers to reach the best trade-off for HIS performances.

  3. Prior-to-Exam: What Activities Enhance Performance?

    Science.gov (United States)

    Rhoads, C. J.; Healy, Therese

    2013-01-01

    Can instructors impact their student performance by recommending an activity just prior to taking an exam? In this study, college students were randomly assigned to one of three treatment groups (study, exercise, or meditation) or a control group. Each group was given two different types of tests; a traditional concept exam, and a non-traditional…

  4. The Effect of Synthetic Vision Enhancements on Landing Flare Performance

    NARCIS (Netherlands)

    Le Ngoc, L.; Borst, C.; Mulder, M.; Van Paassen, M.M.

    2010-01-01

    The usage of heads-down, non-conformal synthetic vision displays for landings below minimums has inherent problems during the flare due to minification effects. Literature showed that pilots can use four visual cues to perform a manual flare maneuver. Amongst their strategies, the Jacobson flare

  5. School Gardens Enhance Academic Performance and Dietary Outcomes in Children

    Science.gov (United States)

    Berezowitz, Claire K.; Bontrager Yoder, Andrea B.; Schoeller, Dale A.

    2015-01-01

    Background: Schools face increasing demands to provide education on healthy living and improve core academic performance. Although these appear to be competing concerns, they may interact beneficially. This article focuses on school garden programs and their effects on students' academic and dietary outcomes. Methods: Database searches in CABI,…

  6. Performance Research Integration Tool (IMPRINT Pro) Maintenance Model Enhancements

    Science.gov (United States)

    2009-09-01

    24 3.4.7 Function 67, “Post Flight ( BPO /PR) Inspection.” ............................. 25 3.4.8 Function 68, “Unscheduled Maintenance...78 7.1 Mx crew performs Preflight/Basic Post-flight (PR/ BPO ...Function 65, "Recovery Inspection." ............................................... 24 Figure 3-15. Function 67, "Post Flight ( BPO /PR) Inspection

  7. Enhancing performance in cricket by using South African cricket ...

    African Journals Online (AJOL)

    Sport psychology in South Africa has for many years been characterised by the deficit perspective on human nature focusing on “what is wrong with sports people”. Psychological Skills Training (PST) programmes have been used to correct these deficits until optimal performance can happen in the “absence of discomfort.

  8. Enhancing Teacher Performance: The Role of Professional Autonomy

    Science.gov (United States)

    Hyslop-Margison, Emery J.; Sears, Alan M.

    2010-01-01

    Current teacher accountability initiatives such as those included in the "No Child Left Behind" legislation in the United States create particular difficulties that impact deleteriously on the performance of professional educators. The quality of public education is undermined when teachers are held accountable to an external authority…

  9. Life context of pharmacological academic performance enhancement among university students--a qualitative approach.

    Science.gov (United States)

    Hildt, Elisabeth; Lieb, Klaus; Franke, Andreas Günter

    2014-03-07

    Academic performance enhancement or cognitive enhancement (CE) via stimulant drug use has received increasing attention. The question remains, however, whether CE solely represents the use of drugs for achieving better academic or workplace results or whether CE also serves various other purposes. The aim of this study was to put the phenomenon of pharmacological academic performance enhancement via prescription and illicit (psycho-) stimulant use (Amphetamines, Methylphenidate) among university students into a broader context. Specifically, we wanted to further understand students' experiences, the effects of use on students and other factors, such as pressure to perform in their academic and private lives. A sample of 18 healthy university students reporting the non-medical use of prescription and illicit stimulants for academic performance enhancement was interviewed in a face-to-face setting. The leading questions were related to the situations and context in which the students considered the non-medical use of stimulants. Based on the resultant transcript, two independent raters identified six categories relating to the life context of stimulant use for academic performance enhancement: Context of stimulant use beyond academic performance enhancement, Subjective experience of enhancement, Timing of consumption, Objective academic results, Side effects, Pressure to perform. The answers reveal that academic performance enhancement through the use of stimulants is not an isolated phenomenon that solely aims at enhancing cognition to achieve better academic results but that the multifaceted life context in which it is embedded is of crucial relevance. The participants not only considered the stimulants advantageous for enhancing academic performance, but also for leading an active life with a suitable balance between studying and time off. The most common reasons given for stimulant use were to maximize time, to increase motivation and to cope with memorizing

  10. Implementation of Parallel and Serial Concatenated Convolutional Codes

    OpenAIRE

    Wu, Yufei

    2000-01-01

    Parallel concatenated convolutional codes (PCCCs), called "turbo codes" by their discoverers, have been shown to perform close to the Shannon bound at bit error rates (BERs) between 1e-4 and 1e-6. Serial concatenated convolutional codes (SCCCs), which perform better than PCCCs at BERs lower than 1e-6, were developed borrowing the same principles as PCCCs, including code concatenation, pseudorandom interleaving and iterative decoding. The first part of this dissertation introduces the fund...

  11. Enhancing performance and reducing stress in sports technological advances

    CERN Document Server

    Ivancevic, Tijana; Greenberg, Ronald

    2015-01-01

    This book is designed to help athletes and individuals interested in high sports performance in their journey towards the perfection of human sports abilities and achievements. It has two main goals: accelerating the acquisition of motor skills and preparing and vigilantly reducing the recovery time after training and competition. The Diamond Sports Protocol (DSP) presents state-of-the-art techniques for current sport and health technologies, particularly neuromuscular electrical stimulation (Sports Wave), oxygen infusion (Oxy Sports), infrared (Sports Infrared Dome) and lactic acid cleaning (Turbo Sports). The book suggest DSP as an essential part of every future athlete's training, competition and health maintenance. The book is for everyone interested in superior sports performance, fast and effective rehabilitation from training and competition and sports injury prevention.

  12. Listening to Mozart does not enhance backwards digit span performance.

    Science.gov (United States)

    Steele, K M; Ball, T N; Runk, R

    1997-06-01

    Rauscher, Shaw, and Ky recently reported that exposure to brief periods of music by Mozart produced a temporary increase in performance on tasks taken from the Stanford-Binet Intelligence Scale-IV. The present study examined whether this effect occurred in performance on a backwards digit span task. In a within-subjects design 36 undergraduates were exposed to 10-min. periods of Mozart music, a recording of rain, or silence. After each stimulus period, undergraduates had three attempts to hear and recall different 9-digit strings in reverse order. No significant differences among treatment conditions were found. There was a significant effect of practice. Results are discussed in terms of the need to isolate the conditions responsible for production of the Mozart effect.

  13. System-level techniques for analog performance enhancement

    CERN Document Server

    Song, Bang-Sup

    2016-01-01

    This book shows readers to avoid common mistakes in circuit design, and presents classic circuit concepts and design approaches from the transistor to the system levels. The discussion is geared to be accessible and optimized for practical designers who want to learn to create circuits without simulations. Topic by topic, the author guides designers to learn the classic analog design skills by understanding the basic electronics principles correctly, and further prepares them to feel confident in designing high-performance, state-of-the art CMOS analog systems. This book combines and presents all in-depth necessary information to perform various design tasks so that readers can grasp essential material, without reading through the entire book. This top-down approach helps readers to build practical design expertise quickly, starting from their understanding of electronics fundamentals. .

  14. Enhancing optical isolator performance in nonreciprocal waveguide arrays.

    Science.gov (United States)

    Levy, Miguel; Carroll, Turhan K; El-Ganainy, Ramy

    2015-01-01

    We investigate the operation of optical isolators based on magneto-optics waveguide arrays beyond the coupled mode analysis. Semi-vectorial beam propagation simulations demonstrate that evanescent tail coupling and the effects of radiation are responsible for degrading the device's performance. Our analysis suggests that these effects can be mitigated when the array size is scaled up. In addition, we propose the use of radiation blockers in order to offset some of these effects, and we show that they provide a dramatic improvement in performance. Finally, we also study the robustness of the system with respect to fabrication tolerances using the coupled mode theory. We show that small, random variations in the system's parameters tend to average out as the number of optical guiding channels increases.

  15. Enhance hospital performance from intellectual capital to business intelligence.

    Science.gov (United States)

    Karami, Mahtab; Fatehi, Mansoor; Torabi, Mashallah; Langarizadeh, Mostafa; Rahimi, Azin; Safdari, Reza

    2013-01-01

    Business intelligence (BI) refers to technologies, tools, and practices for collecting, integrating, analyzing, and presenting large volumes of information to enable better decision making. The aim of this study is to provide a general overview of BI and its impacts on improving hospital performance. In this paper, literature is reviewed on the concept, classification, and structure of intellectual capital and BI. Research on the building of BI and its impact on the performance of hospitals are briefly summarized. Some areas in healthcare which can utilize BI benefits, including radiology, are also discussed. Used properly, BI is an effective communication tool that can enable hospitals to reach strategic goals and objectives and can also help eliminate information asymmetry.

  16. Does Competition Enhance Performance or Cheating? A Laboratory Experiment

    OpenAIRE

    Schwieren, Christiane; Weichselbaumer, Doris

    2008-01-01

    In this paper we experimentally test whether competing for a desired reward does not only affect individuals’ performance, but also their tendency to cheat. Recent doping scandals in sports as well as forgery and plagiarism scandals in academia have been partially explained by „competitive pressures“, which suggests a link between competition and cheating. In our experiment subjects conduct a task where they have the possibility to make use of illegitimate tools to better their results. We fi...

  17. Exploring the Implications of Emotional Intelligence to Enhance Employees’ Performance

    OpenAIRE

    Muhammad Bashir Khan; Nadia Asghar; Muhammad Waqas Chughtai

    2013-01-01

    Emotional intelligence (EI) is an effective tool to increase organizational productivity. This study depicts the impact of EI on employees’ performance who are engaged with customer services by using four elements i.e. self awareness, self management, social awareness and relationship management. A sample of 120 respondents was selected from four paint manufacturing companies in Pakistan. The primary data was collected through the structured questionnaire and simple regression method was used...

  18. Sodium nitrate supplementation does not enhance performance of endurance athletes.

    Science.gov (United States)

    Bescós, Raúl; Ferrer-Roca, Ventura; Galilea, Pedro A; Roig, Andreu; Drobnic, Franchek; Sureda, Antoni; Martorell, Miquel; Cordova, Alfredo; Tur, Josep A; Pons, Antoni

    2012-12-01

    Supplementation with inorganic nitrate has been suggested to be an ergogenic aid for athletes as nitric oxide donor. The purpose of this study was to determine whether ingestion of inorganic sodium nitrate benefits well-trained athletes performing a 40-min exercise test in laboratory conditions. In addition, we investigated the effect of this supplement on plasma levels of endothelin-1 (ET-1) and in nitrated proteins. Thirteen trained athletes participated in this randomized, double-blind, crossover study. They performed a 40-min cycle ergometer distance-trial test after two 3-d periods of dietary supplementation with sodium nitrate (10 mg·kg of body mass) or placebo. Concentration of plasma nitrate (256 ± 35 μM) and nitrite (334 ± 86 nM) increased significantly (P nitrate supplementation compared with placebo (nitrate: 44 ± 11 μM; nitrite: 187 ± 43 nM). In terms of exercise performance, there were no differences in either the mean distance (nitrate: 26.4 ± 1.1 km; placebo: 26.3 ± 1.2 km; P = 0.61) or mean power output (nitrate: 258 ± 28 W; placebo: 257 ± 28 W; P = 0.89) between treatments. Plasma ET-1 increased significantly (P nitrate (4.0 ± 0.8 pg·mL) and placebo (2.4 ± 0.4 pg·mL) conditions. This increase was significantly greater (P nitrate group. Levels of nitrated proteins did not differ between treatments (nitrate: preexercise, 91% ± 23%; postexercise, 81% ± 23%; placebo: preexercise, 95% ± 20%; postexercise, 99% ± 19%). Sodium nitrate supplementation did not improve a 40-min distance-trial performance in endurance athletes. In addition, concentration of plasma ET-1 increased significantly after exercise after supplementation with sodium nitrate.

  19. Dynamic performance enhancement of microgrids by advanced sliding mode controller

    Energy Technology Data Exchange (ETDEWEB)

    Sofla, Mohammadhassan Abdollahi [Electrical Engineering and Computer Science Dept., University of Toledo, Ohio (United States); Gharehpetian, Gevorg B. [Electrical Engineering Dept., Amirkabir University of Technology, Tehran (Iran, Islamic Republic of)

    2011-01-15

    Dynamics are the most important problems in the microgrid operation. In the islanded microgrid, the mismatch of parallel operations of inverters during dynamics can result in the instability. This paper considers severe dynamics which can occur in the microgrid. Microgrid can have different configurations with different load and generation dynamics which are facing voltage disturbances. As a result, microgrid has many uncertainties and is placed in the distribution network where is full of voltage disturbances. Moreover, characteristics of the distribution network and distributed energy resources in the islanded mode make microgrid vulnerable and easily lead to instability. The main aim of this paper is to discuss the suitable mathematical modeling based on microgrid characteristics and to design properly inner controllers to enhance the dynamics of microgrid with uncertain and changing parameters. This paper provides a method for inner controllers of inverter-based distributed energy resources to have a suitable response for different dynamics. Parallel inverters in distribution networks were considered to be controlled by nonlinear robust voltage and current controllers. Theoretical prove beyond simulation results, reveal evidently the effectiveness of the proposed controller. (author)

  20. Enhancing thermoelectric performance of Cu2Se by doping Te.

    Science.gov (United States)

    Zhu, Yong-Bin; Zhang, Bo-Ping; Liu, Yong

    2017-10-18

    Owing to the excellent electrical properties and inherently complex crystal structure, Cu2Se has been considered as a promising thermoelectric (TE) material. Herein, a series of Cu2Se1-xTex (x = 0, 0.02, 0.04, 0.06, and 0.08) bulk samples are prepared by combining mechanical alloying (MA) and spark plasma sintering (SPS) to investigate the effect of Te content (x) on the phase structure, microstructure and TE properties of stoichiometric Cu2Se. It is found that a maximum TE figure of merit (ZT) value of 1.25 could be achieved for Cu2Se0.98Te0.02 sample at 773 K, which essentially stemmed from the elevated power factor (PF) and reduced thermal conductivity (κ). The results obtained in our study indicate that the introduction of Te into stoichiometric Cu2Se is an effective and convenient strategy to improve ZT by enhancing PF and decreasing κ.

  1. Dandelion-shaped nanostructures for enhancing omnidirectional photovoltaic performance

    Science.gov (United States)

    Kuo, Shou-Yi; Hsieh, Ming-Yang; Han, Hau-Vei; Lai, Fang-I.; Tsai, Yu-Lin; Yang, Jui-Fu; Chuang, Tsung-Yeh; Kuo, Hao-Chung

    2013-05-01

    Broadband and omnidirectional light harvesting is important in photovoltaic technology because of its wide spectral range of radiation and the sun's movement. This study reports the fabrication and characterization of zinc oxide (ZnO) dandelions on Cu(In,Ga)Se2 (CIGS) solar cells. The fabrication of dandelions involves the combination of self-assembled polystyrene (PS) nanospheres and the hydrothermal method, which is one of the simplest and cheapest methods of fabricating a three-dimensional, closely packed periodic structure. This study also investigates the optimization on dimension of the PS nanospheres using the rigorous coupled-wave analysis (RCWA) method. This study uses an angle-resolved reflectance spectroscope and a homemade rotatable photo I-V measurement to investigate the omnidirectional and broadband antireflections of the proposed dandelion structure. Under a simulated one-sun condition and a light incident angle of up to 60°, cells with ZnO dandelions arrays enhanced the short-circuit current density by 31.87%. Consequently, ZnO dandelions are suitable for creating an omnidirectionally antireflective coating for photovoltaic devices.

  2. Enhancement of the thermoelectric performance of oxygen substituted bismuth telluride

    Science.gov (United States)

    Van Quang, Tran; Kim, Miyoung

    2017-12-01

    We carried out first-principles calculations based on density functional theory and the semi-classical Boltzmann transport theory to study the effect of oxygen substitution on the electronic structure and thermoelectric properties of bismuth telluride. The newly formed compound, Bi2O2Te, is found to be a narrow bandgap semiconductor with the bandgap of Eg = 0.13 eV. The presence of a flat band close to the valence band maximum gives rise to a steep slope of density of states near Fermi energy, leading to a significant enhancement of the Seebeck coefficient. As a result, the thermoelectric power factor of Bi2O2Te is significantly improved by controlling the carrier concentration, and the maximum power factor increased with temperature. Assuming the experiment-thermal conductivity, Bi2O2Te exhibits a high figure of merit of ZT ˜1.27 around 600 K for the p-type doping, which matches or exceeds ZT of the state-of-the-art thermoelectric materials in this temperature range. This suggests that Bi2O2Te with p-type doping is a new promising material for use in the moderate-temperature thermoelectric energy conversion.

  3. Performance Enhancement of Dental Composites Using Electrospun Nanofibers

    Directory of Open Access Journals (Sweden)

    H. Dodiuk-Kenig

    2008-01-01

    Full Text Available The objective of the present study is to investigate the effect of electrospun nanofiber reinforcement on the properties of commercially available, hyperbranched polymer modified (Hybrane, 0.3 wt.% DSM dental formulations. The emergence of functionalized nanoscale reinforcements having large surface area (hundreds of square meters/gram has enabled the design of novel nanocomposites with new and complex structures leading to enhanced mechanical and physical properties. Electrospun nanofibers from a range of polymer chemistries (PVOH, PLLA, Nylon 6 have been investigated as a reinforcing phase at levels between 0.01 and 0.3 wt.%, with and without a silane coupling agent surface treatment. The experimental results indicate that 0.05 wt.% reinforcement with 250 nm diameter PVOH nanofibers leads to a 30% improvement in compressive strength, coupled with a shrinkage reduction of about 50%. Electrospun fiber reinforcement by other chemistries or at other diameters showed either no property improvement or led to property loss.

  4. Performance enhancement of PV cells through micro-channel cooling

    Directory of Open Access Journals (Sweden)

    Muzaffar Ali

    2015-11-01

    Full Text Available Efficiency of a PV cell is strongly dependent on its surface temperature. The current study is focused to achieve maximum efficiency of PV cells even in scorching temperatures in hot climates like Pakistan where the cell surface temperatures can even rise up to around 80 ℃. The study includes both the CFD and real time experimental investigations of a solar panel using micro channel cooling. Initially, CFD analysis is performed by developing a 3D model of a Mono-Crystalline cell with micro-channels to analyze cell surface temperature distribution at different irradiance and water flow rates. Afterwards, an experimental setup is developed for performance investigations under the real conditions of an open climate of a Pakistan's city, Taxila. Two 35W panels are manufactured for the experiments; one is based on the standard manufacturing procedure while other cell is developed with 4mm thick aluminum sheet having micro-channels of cross-section of 1mm by 1mm. The whole setup also includes different sensors for the measurement of solar irradiance, cell power, surface temperature and water flow rates. The experimental results show that PV cell surface temperature drop of around 15 ℃ is achieved with power increment of around 14% at maximum applied water flow rate of 3 LPM. Additionally, a good agreement is also found between CFD and experimental results. Therefore, that study clearly shows that a significant performance improvement of PV cells can be achieved through the proposed cell cooling technique.

  5. Enhancing The National Map Through Tactical Planning and Performance Monitoring

    Science.gov (United States)

    ,

    2008-01-01

    Tactical planning and performance monitoring are initial steps toward improving 'the way The National Map works' and supporting the U.S. Geological Survey (USGS) Science Strategy. This Tactical Performance Planning Summary for The National Map combines information from The National Map 2.0 Tactical Plan and The National Map Performance Milestone Matrix. The National Map 2.0 Tactical Plan is primarily a working document to guide The National Map program's execution, production, and metrics monitoring for fiscal years (FY) 2008 and 2009. The Tactical Plan addresses data, products, and services, as well as supporting and enabling activities. The National Map's 2-year goal for FY 2008 and FY 2009 is to provide a range of geospatial products and services that further the National Spatial Data Infrastructure and underpin USGS science. To do this, the National Geospatial Program will develop a renewed understanding during FY 2008 of key customer needs and requirements, develop the infrastructure to support The National Map business model, modernize its business processes, and reengineer its workforce. Priorities for The National Map will be adjusted if necessary to respond to changes to the project that may impact resources, constrain timeframes, or change customer needs. The supporting and enabling activities that make it possible to produce the products and services of The National Map will include partnership activities, improved compatibility of systems, outreach, and integration of data themes.

  6. Perception of Breakfast Ingestion Enhances High Intensity Cycling Performance.

    Science.gov (United States)

    Mears, Stephen A; Dickinson, Kathryn; Bergin-Taylor, Kurt; Dee, Reagan; Kay, Jack; James, Lewis J

    2017-09-27

    To examine the effect on short duration, high intensity cycling time trial performance when a semi-solid breakfast containing carbohydrate or a taste and texture matched placebo is ingested 90 minutes pre-exercise compared to a water control. Thirteen well trained cyclists (25 ± 8 years, 71.1 ± 5.9 kg, 1.76 ± 0.04 m, 383 ± 46 Wmax, VO2peak 4.42 ± 0.53 L·min(-1)) performed three experimental trials examining breakfast ingestion 90 minutes before a 10 minute steady state cycle (60% Wmax) and a ~20 minute time trial (to complete a workload target of 376 ± 36 kJ). Subjects consumed either water (WAT), a semi-solid carbohydrate breakfast (2 g carbohydrate·kg(-1) body mass; CHO) or a taste and texture matched placebo (PLA). Blood lactate and glucose concentrations were measured periodically throughout the rest and exercise periods. The time trial was completed quicker in CHO (1120 ± 69 s; P=0.006) and PLA (1112 ± 50 s; P=0.030) compared to WAT (1146 ± 74 s). Ingestion of carbohydrate caused an increase in blood glucose concentration throughout the rest period in CHO (peak at 30 minutes rest: 7.37 ± 1.10 mmol·l(-1); Pbreakfast (PLA or CHO) 90 minutes prior to the start of exercise. The improvement in performance is likely attributable to a psychological rather than physiological effect.

  7. Serial blood T cell repertoire alterations in multiple sclerosis patients; correlation with clinical and MRI parameters.

    Science.gov (United States)

    Laplaud, David-Axel; Berthelot, Laureline; Miqueu, Patrick; Bourcier, Kasia; Moynard, Julien; Oudinet, Yannick; Guillet, Marina; Ruiz, Catherine; Oden, Neal; Brouard, Sophie; Guttmann, Charles R G; Weiner, Howard L; Khoury, Samia J; Soulillou, Jean-Paul

    2006-08-01

    A significant skewing of the peripheral T cell repertoire has been shown in relapsing-remitting multiple sclerosis (MS). Most of the studies already performed in this field are cross-sectional and therefore, little is known of the T cell repertoire evolution over time in MS and the correlation of T cell repertoire variation with clinical and MRI parameters. This study was performed on serially harvested frozen PBMC from nine untreated MS patients (27 samples) and 14 healthy individuals. The blood T cell repertoire of each patient was analysed at the complementarity determining region 3 (CDR3) level and compared with a monthly MRI scan performed over a six month period with assessment of T2 lesion load and gadolinium enhancing lesions. A highly significant blood T cell repertoire skewing was observed in MS patients as compared with healthy controls (p<0.01). In addition, the number of altered Vbeta families correlated significantly with both the T2 lesion volume and the number of gadolinium enhancing lesions as assessed by MRI (Spearman correlation tests, r=0.51 and r=0.44, p<0.01 and p<0.05 respectively). Furthermore, the variation of the number of altered Vbeta families over time also correlated with the appearance of new gadolinium enhancing lesions (r=0.36, p=0.05). These findings which need confirmation on larger serial cohorts, suggest an association between the magnitude of TCRBV CDR3 length distribution alterations in the peripheral blood of MS patients and the disease process.

  8. Serial killers with military experience: applying learning theory to serial murder.

    Science.gov (United States)

    Castle, Tammy; Hensley, Christopher

    2002-08-01

    Scholars have endeavored to study the motivation and causality behind serial murder by researching biological, psychological, and sociological variables. Some of these studies have provided support for the relationship between these variables and serial murder. However, the study of serial murder continues to be an exploratory rather than explanatory research topic. This article examines the possible link between serial killers and military service. Citing previous research using social learning theory for the study of murder, this article explores how potential serial killers learn to reinforce violence, aggression, and murder in military boot camps. As with other variables considered in serial killer research, military experience alone cannot account for all cases of serial murder. Future research should continue to examine this possible link.

  9. Carbon dioxide enhanced oil recovery performance according to the literature

    Science.gov (United States)

    Olea, Ricardo A.

    2017-07-17

    IntroductionThe need to increase the efficiency of oil recovery and environmental concerns are bringing to prominence the use of carbon dioxide (CO2) as a tertiary recovery agent. Assessment of the impact of flooding with CO2 all eligible reservoirs in the United States not yet undergoing enhanced oil recovery (EOR) requires making the best possible use of the experience gained in 40 years of applications. Review of the publicly available literature has located relevant CO2-EOR information for 53 units (fields, reservoirs, pilot areas) in the United States and 17 abroad.As the world simultaneously faces an increasing concentration of CO2 in the atmosphere and a higher demand for fossil fuels, the CO2-EOR process continues to gain popularity for its efficiency as a tertiary recovery agent and for the potential for having some CO2 trapped in the subsurface as an unintended consequence of the enhanced production (Advanced Resources International and Melzer Consulting, 2009). More extensive application of CO2-EOR worldwide, however, is not making it significantly easier to predict the exact outcome of the CO2 flooding in new reservoirs. The standard approach to examine and manage risks is to analyze the intended target by conducting laboratory work, running simulation models, and, finally, gaining field experience with a pilot test. This approach, though, is not always possible. For example, assessment of the potential of CO2-EOR at the national level in a vast country such as the United States requires making forecasts based on information already available.Although many studies are proprietary, the published literature has provided reviews of CO2-EOR projects. Yet, there is always interest in updating reports and analyzing the information under new perspectives. Brock and Bryan (1989) described results obtained during the earlier days of CO2-EOR from 1972 to 1987. Most of the recovery predictions, however, were based on intended injections of 30 percent the size of

  10. Feedback-controlled stimulation enhances human paralyzed muscle performance.

    Science.gov (United States)

    Shields, Richard K; Dudley-Javoroski, Shauna; Cole, Keith R

    2006-11-01

    Chronically paralyzed muscle requires extensive training before it can deliver a therapeutic dose of repetitive stress to the musculoskeletal system. Neuromuscular electrical stimulation, under feedback control, may subvert the effects of fatigue, yielding more rapid and extensive adaptations to training. The purposes of this investigation were to 1) compare the effectiveness of torque feedback-controlled (FDBCK) electrical stimulation with classic open-loop constant-frequency (CONST) stimulation, and 2) ascertain which of three stimulation strategies best maintains soleus torque during repetitive stimulation. When torque declined by 10%, the FDBCK protocol modulated the base stimulation frequency in three ways: by a fixed increase, by a paired pulse (doublet) at the beginning of the stimulation train, and by a fixed decrease. The stimulation strategy that most effectively restored torque continued for successive contractions. This process repeated each time torque declined by 10%. In fresh muscle, FDBCK stimulation offered minimal advantage in maintaining peak torque or mean torque over CONST stimulation. As long-duration fatigue developed in subsequent bouts, FDBCK stimulation became most effective ( approximately 40% higher final normalized torque than CONST). The high-frequency strategy was selected approximately 90% of the time, supporting that excitation-contraction coupling compromise and not neuromuscular transmission failure contributed to fatigue of paralyzed muscle. Ideal stimulation strategies may vary according to the site of fatigue; this stimulation approach offered the advantage of online modulation of stimulation strategies in response to fatigue conditions. Based on stress-adaptation principles, FDBCK-controlled stimulation may enhance training effects in chronically paralyzed muscle.

  11. Polyphosphate Kinase from Activated Sludge Performing Enhanced Biological Phosphorus Removal†

    Science.gov (United States)

    McMahon, Katherine D.; Dojka, Michael A.; Pace, Norman R.; Jenkins, David; Keasling, Jay D.

    2002-01-01

    A novel polyphosphate kinase (PPK) was retrieved from an uncultivated organism in activated sludge carrying out enhanced biological phosphorus removal (EBPR). Acetate-fed laboratory-scale sequencing batch reactors were used to maintain sludge with a high phosphorus content (approximately 11% of the biomass). PCR-based clone libraries of small subunit rRNA genes and fluorescent in situ hybridization (FISH) were used to verify that the sludge was enriched in Rhodocyclus-like β-Proteobacteria known to be associated with sludges carrying out EBPR. These organisms comprised approximately 80% of total bacteria in the sludge, as assessed by FISH. Degenerate PCR primers were designed to retrieve fragments of putative ppk genes from a pure culture of Rhodocyclus tenuis and from organisms in the sludge. Four novel ppk homologs were found in the sludge, and two of these (types I and II) shared a high degree of amino acid similarity with R. tenuis PPK (86 and 87% similarity, respectively). Dot blot analysis of total RNA extracted from sludge demonstrated that the Type I ppk mRNA was present, indicating that this gene is expressed during EBPR. Inverse PCR was used to obtain the full Type I sequence from sludge DNA, and a full-length PPK was cloned, overexpressed, and purified to near homogeneity. The purified PPK has a specific activity comparable to that of other PPKs, has a requirement for Mg2+, and does not appear to operate in reverse. PPK activity was found mainly in the particulate fraction of lysed sludge microorganisms. PMID:12324346

  12. Cannabis use to enhance sportive and non-sportive performances among French sport students.

    Science.gov (United States)

    Lorente, Fabrice Olivier; Peretti-Watel, Patrick; Grelot, Laurent

    2005-08-01

    Despite a large public health interest in substance use among athletes, only a few works have addressed illicit drug use in relation with sport practice. We have studied cannabis use to enhance both sportive and non-sportive performance among French sport university students. An anonymous self-reported questionnaire was administered to a sample of students from six Sport Science Universities from Southern France. Information on sport practice and cannabis use (frequency, quantity, motives) was collected. Males were more prone to have already used cannabis to enhance non-sportive performance as well as sportive performance. The simultaneous equation model indicated that both kinds of enhancing-substance use were endogenous: cannabis use to enhance sportive performance leads to cannabis use to enhance non-sportive performance and reciprocally. Moreover, the relaxing properties of cannabis may be frequently used to enhance performance. Cannabis use to enhance sportive performance was positively related to the competitive level and to sliding sports. The present study helps to improve understanding on an empirical paradox about the relationship between doping agents use and so-called 'recreational' drug use among athletes. Indeed, people who use doping agents may also use 'recreational' drugs for a 'non-recreational' purpose.

  13. Enhancing Cellulase Commercial Performance for the Lignocellulosic Biomass Industry

    Energy Technology Data Exchange (ETDEWEB)

    Jarnigan, Alisha [Danisco, US Inc., Copenhagen (Denmark)

    2016-06-07

    Cellulase enzyme loading (Bt-G) for the economic conversion of lignocellulosic biomass to ethanol is on of the key challenges identified in the Biomass Program of DOE/EERE. The goal of Danisco’s project which ran from 2008 to 2012, was to address the technical challenge by creating more efficient enzyme that could be used at lower doses, thus reducing the enzymes’ cost contribution to the conversio process. We took the approach of protein engineering of cellulase enzymes to overcome the enzymati limitations in the system of cellulosic-hydrolyzing enzymes to improve performance in conversion o biomass, thereby creating a more effective enzyme mix.

  14. Enhancing Functional Performance using Sensorimotor Adaptability Training Programs

    Science.gov (United States)

    Bloomberg, J. J.; Mulavara, A. P.; Peters, B. T.; Brady, R.; Audas, C.; Ruttley, T. M.; Cohen, H. S.

    2009-01-01

    During the acute phase of adaptation to novel gravitational environments, sensorimotor disturbances have the potential to disrupt the ability of astronauts to perform functional tasks. The goal of this project is to develop a sensorimotor adaptability (SA) training program designed to facilitate recovery of functional capabilities when astronauts transition to different gravitational environments. The project conducted a series of studies that investigated the efficacy of treadmill training combined with a variety of sensory challenges designed to increase adaptability including alterations in visual flow, body loading, and support surface stability.

  15. Evidence for Attentional Gradient in the Serial Position Memory Curve from Event-related Potentials

    Science.gov (United States)

    Azizian, Allen; Polich, John

    2009-01-01

    The occurrence of primacy versus recency effects in free recall is suggested to reflect either two distinct memory systems, or the operation of a single system that is modulated by allocation of attention and less vulnerable to interference. Behavioral and event-related brain potential (ERPs) measures were used to investigate the encoding substrates of the serial position curve and subsequent recall in young adults. Participants were instructed to remember lists of words consisting of 12 common nouns each presented once every 1.5 sec, with a recall signal following the last word to indicate that all remembered items should be written on paper. This procedure was repeated for 20 different word lists. Both performance and late ERP amplitudes reflected classic recall serial position effects. Greater recall and larger late positive component amplitudes were obtained for the primacy and recency items, with less recall and smaller amplitudes for the middle words. The late positive component was larger for recalled compared to unrecalled primacy items, but it did not differ between memory performance outcomes for the recency items. The close relationship between the enhanced amplitude and primacy retrieval supports the view that this positive component reflects one of a process series related to attentional gradient and encoding of events for storage in memory. Recency effects appear to index operations determined by the anticipation of the last stimulus presentation, which occurred for both recalled and unrecalled memory items. Theoretical implications are discussed. PMID:17892393

  16. Recency and suffix effects in serial recall of musical stimuli.

    Science.gov (United States)

    Greene, R L; Samuel, A G

    1986-10-01

    Auditory presentation of verbal items leads to larger recency effects in recall than visual presentation. This enhanced recency can be eliminated if a stimulus suffix (an irrelevant sound) follows the last item. Four experiments tested the hypothesis that recency and suffix effects in serial recall result from a speech-specific process. It was demonstrated that serial recall of musical notes played on a piano exhibited substantial recency effects. These recency effects were reduced when the list items were followed by either a piano chord or the word start. However, a white-noise suffix had no effect on recency. This pattern of data is consistent with current work on auditory perception and places constraints on theories of recency and suffix effects.

  17. School Gardens Enhance Academic Performance and Dietary Outcomes in Children.

    Science.gov (United States)

    Berezowitz, Claire K; Bontrager Yoder, Andrea B; Schoeller, Dale A

    2015-08-01

    Schools face increasing demands to provide education on healthy living and improve core academic performance. Although these appear to be competing concerns, they may interact beneficially. This article focuses on school garden programs and their effects on students' academic and dietary outcomes. Database searches in CABI, Web of Science, Web of Knowledge, PubMed, Education Full Text, Education Resources Information Center (ERIC), and PsychINFO were conducted through May 2013 for peer-reviewed literature related to school-day garden interventions with measures of dietary and/or academic outcomes. Among 12 identified garden studies with dietary measures, all showed increases/improvements in predictors of fruit and vegetable (FV) consumption. Seven of these also included self-reported FV intake with 5 showing an increase and 2 showing no change. Four additional interventions that included a garden component measured academic outcomes; of these, 2 showed improvements in science achievement and 1 measured and showed improvements in math scores. This small set of studies offers evidence that garden-based learning does not negatively impact academic performance or FV consumption and may favorably impact both. Additional studies with more robust experimental designs and outcome measures are necessary to understand the effects of experiential garden-based learning on children's academic and dietary outcomes. © 2015, American School Health Association.

  18. Grayscale performance enhancement for time-multiplexing light field rendering.

    Science.gov (United States)

    Su, Chen; Zhong, Qing; Peng, Yifan; Xu, Liang; Wang, Rui; Li, Haifeng; Liu, Xu

    2015-12-14

    One of the common approaches to compensate for the grayscale performance limitation in time-multiplexing light field displays is to employ a halftone technique. We propose an ordered-dithering halftone algorithm based on a 3-dimension super-mask to increase the gray levels of the time-multiplexing light field display. Our method makes full use of the overlapping perceived pixels which are caused by the time-multiplexing design, such that effectively trading-off the spatial resolution and color performance. A real-time rendering time-multiplexing display prototype is built to validate the proposed halftone algorithm. We conducted a user study to evaluate the quality of display scenes dithered by different super-mask configuration, which showed the consistency with the parameters we pre-calculated. The 3D ordered-dithering algorithm is able to present better visual perception than the conventional halftone algorithms with respect to grayscale representation, and flexible to be applied in different time-multiplexing light field display systems.

  19. Moringa oleifera extract enhances sexual performance in stressed rats.

    Science.gov (United States)

    Prabsattroo, Thawatchai; Wattanathorn, Jintanaporn; Iamsaard, Sitthichai; Somsapt, Pichet; Sritragool, Opass; Thukhummee, Wipawee; Muchimapura, Supaporn

    2015-03-01

    Aphrodisiacs are required to improve male sexual function under stressful conditions. Due to the effects of oxidative stress and dopamine on male sexual function, we hypothesized that Moringa oleifera leaves might improve male sexual dysfunction induced by stress. Therefore, the effects on various factors playing important roles in male sexual behavior, such as antioxidant effects, the suppression of monoamine and phosphodiesterase type 5 (PDE-5) activities, serum testosterone and corticosterone levels, and histomorphological changes in the testes, of a hydroethanolic extract of M. oleifera leaves were investigated. Various doses of extract including 10, 50, and 250 mg/kg body weight (BW) were given orally to male Wistar rats before exposure to 12 h-immobilization stress for 7 d. The results demonstrated that the extract showed both antioxidant and monoamine oxidase type B (MAO-B) suppression activities. At 7 d of treatment, the low dose of extract improved sexual performance in stress-exposed rats by decreasing intromission latency and increasing intromission frequency. It also suppressed PDE-5 activity, decreased serum corticosterone level, but increased serum testosterone, numbers of interstitial cells of Leydig and spermatozoa. The increased numbers of interstitial cells of Leydig and spermatozoa might have been due to the antioxidant effect of the extract. The increased sexual performance during the intromission phase might have been due to the suppression of MAO-B and PDE-5 activities and increased testosterone. Therefore, M. oleifera is a potential aphrodisiac, but further research concerning the precise underlying mechanisms is still needed.

  20. Moringa oleifera extract enhances sexual performance in stressed rats*

    Science.gov (United States)

    Prabsattroo, Thawatchai; Wattanathorn, Jintanaporn; Iamsaard, Sitthichai; Somsapt, Pichet; Sritragool, Opass; Thukhummee, Wipawee; Muchimapura, Supaporn

    2015-01-01

    Aphrodisiacs are required to improve male sexual function under stressful conditions. Due to the effects of oxidative stress and dopamine on male sexual function, we hypothesized that Moringa oleifera leaves might improve male sexual dysfunction induced by stress. Therefore, the effects on various factors playing important roles in male sexual behavior, such as antioxidant effects, the suppression of monoamine and phosphodiesterase type 5 (PDE-5) activities, serum testosterone and corticosterone levels, and histomorphological changes in the testes, of a hydroethanolic extract of M. oleifera leaves were investigated. Various doses of extract including 10, 50, and 250 mg/kg body weight (BW) were given orally to male Wistar rats before exposure to 12 h-immobilization stress for 7 d. The results demonstrated that the extract showed both antioxidant and monoamine oxidase type B (MAO-B) suppression activities. At 7 d of treatment, the low dose of extract improved sexual performance in stress-exposed rats by decreasing intromission latency and increasing intromission frequency. It also suppressed PDE-5 activity, decreased serum corticosterone level, but increased serum testosterone, numbers of interstitial cells of Leydig and spermatozoa. The increased numbers of interstitial cells of Leydig and spermatozoa might have been due to the antioxidant effect of the extract. The increased sexual performance during the intromission phase might have been due to the suppression of MAO-B and PDE-5 activities and increased testosterone. Therefore, M. oleifera is a potential aphrodisiac, but further research concerning the precise underlying mechanisms is still needed. PMID:25743119

  1. Enhancing the Performance of Vanadium Redox Flow Batteries using Quinones

    Science.gov (United States)

    Mulcahy, James W., III

    The global dependence on fossil fuels continues to increase while the supply diminishes, causing the proliferation in demand for renewable energy sources. Intermittent renewable energy sources such as wind and solar, require electrochemical storage devices in order to transfer stored energy to the power grid at a constant output. Redox flow batteries (RFB) have been studied extensively due to improvements in scalability, cyclability and efficiency over conventional batteries. Vanadium redox flow batteries (VRFB) provide one of the most comprehensive solutions to energy storage in relation to other RFBs by alleviating the problem of cross-contamination. Quinones are a class of organic compounds that have been extensively used in chemistry, biochemistry and pharmacology due to their catalytic properties, fast proton-coupled electron transfer, good chemical stability and low cost. Anthraquinones are a subcategory of quinones and have been utilized in several battery systems. Anthraquinone-2, 6-disulfonic acid (AQDS) was added to a VRFB in order to study its effects on cyclical performance. This study utilized carbon paper electrodes and a Nafion 117 ion exchange membrane for the membrane-electrode assembly (MEA). The cycling performance was investigated over multiple charge and discharge cycles and the addition of AQDS was found to increase capacity efficiency by an average of 7.6% over the standard VRFB, while decreasing the overall cycle duration by approximately 18%. It is thus reported that the addition of AQDS to a VRFB electrolyte has the potential to increase the activity and capacity with minimal increases in costs.

  2. Smarter Grid through Collective Intelligence: User Awareness for Enhanced Performance

    Directory of Open Access Journals (Sweden)

    Marcel Macarulla

    2015-02-01

    Full Text Available Purpose – This paper examines the scenario of a university campus, and the impact on energy consumption of the awareness of building managers and users (lecturers, students and administrative staff.Design/methodology/approach – This study draws a comparison between direct fruition of the information by both skilled (building managers and unskilled (users recipients, and the effect of peer pressure and beneficial competition between users in applying the good practices. In fact, the usage of edutainment, implemented by the automatic publication on the Twitter platform of energy consumption data from different users, can promote general users’ awareness on best practices and their effect on energy consumption. In addition, the use of a social network platform allows the interaction between users, sharing experiences and increasing the collective intelligence in the energy efficiency field.Findings – Tests revealed that enhanced awareness helped managers to identify strategies that, if implemented in the whole building, could reduce energy consumption by about 6%. The tests on university users’ awareness hint that the expected energy savings can reach 9%, in addition to the previous 6%. In fact, the measures were implemented in one of the three common rooms, and at building level the total energy consumption decreased by 3.42%, proving that a large deal of energy can be saved by capillary actions targeting society at large. The emerging collective intelligence of the final users ends up having a stronger effect on energy saving than the actions of more educated professionals.Practical implications – The approach used in this paper moved the burden of evolving the energy saving strategies to new scenarios onto the collective intelligence of the users, by connecting the users – and their experiences in new scenarios – using a social network to provide guidelines to other users involved in the same decision processes

  3. Does electrical stimulation enhance post-exercise performance recovery?

    Science.gov (United States)

    Babault, Nicolas; Cometti, Carole; Maffiuletti, Nicola A; Deley, Gaëlle

    2011-10-01

    Elite sport requires high-volume and high-intensity training that inevitably induces neuromuscular fatigue detrimental for physical performance. Improving recovery processes is, therefore, fundamental and to this, a wide variety of recovery modalities could be proposed. Among them, neuromuscular electrical stimulation is largely adopted particularly by endurance-type and team sport athletes. This type of solicitation, when used with low stimulation frequencies, induces contractions of short duration and low intensity comparable to active recovery. This might be of interest to favour muscle blood flow and therefore metabolites washout to accelerate recovery kinetics during and after fatiguing exercises, training sessions or competition. However, although electrical stimulation is often used for recovery, limited evidence exists regarding its effects for an improvement of most physiological variables or reduced subjective rating of muscle soreness. Therefore, the main aim of this brief review is to present recent results from the literature to clarify the effectiveness of electrical stimulation as a recovery modality.

  4. Scalable fabrication of nanomaterials based piezoresistivity sensors with enhanced performance

    Science.gov (United States)

    Hoang, Phong Tran

    Nanomaterials are small structures that have at least one dimension less than 100 nanometers. Depending on the number of dimensions that are not confined to the nanoscale range, nanomaterials can be classified into 0D, 1D and 2D types. Due to their small sizes, nanoparticles possess exceptional physical and chemical properties which opens a unique possibility for the next generation of strain sensors that are cheap, multifunctional, high sensitivity and reliability. Over the years, thanks to the development of new nanomaterials and the printing technologies, a number of printing techniques have been developed to fabricate a wide range of electronic devices on diverse substrates. Nanomaterials based thin film devices can be readily patterned and fabricated in a variety of ways, including printing, spraying and laser direct writing. In this work, we review the piezoresistivity of nanomaterials of different categories and study various printing approaches to utilize their excellent properties in the fabrication of scalable and printable thin film strain gauges. CNT-AgNP composite thin films were fabricated using a solution based screen printing process. By controlling the concentration ratio of CNTs to AgNPs in the nanocomposites and the supporting substrates, we were able to engineer the crack formation to achieve stable and high sensitivity sensors. The crack formation in the composite films lead to piezoresistive sensors with high GFs up to 221.2. Also, with a simple, low cost, and easy to scale up fabrication process they may find use as an alternative to traditional strain sensors. By using computer controlled spray coating system, we can achieve uniform and high quality CNTs thin films for the fabrication of strain sensors and transparent / flexible electrodes. A simple diazonium salt treatment of the pristine SWCNT thin film has been identified to be efficient in greatly enhancing the piezoresistive sensitivity of SWCNT thin film based piezoresistive sensors

  5. Railplug Ignition System for Enhanced Engine Performance and Reduced Maintenance

    Energy Technology Data Exchange (ETDEWEB)

    DK Ezekoye; Matt Hall; Ron Matthews

    2005-08-01

    This Final Technical Report discusses the progress that was made on the experimental and numerical tasks over the duration of this project. The primary objectives of the project were to (1) develop an improved understanding of the spark ignition process, and (2) develop the railplug as an improved ignitor for large bore stationary natural gas engines. We performed fundamental experiments on the physical processes occurring during spark ignition and used the results from these experiments to aid our development of the most complete model of the spark ignition process ever devised. The elements in this model include (1) the dynamic response of the ignition circuit, (2) a chemical kinetics mechanism that is suitable for the reactions that occur in the plasma, (3) conventional flame propagation kinetics, and (4) a multi-dimensional formulation so that bulk flow through the spark gap can be incorporated. This model (i.e., a Fortran code that can be used as a subroutine within an engine modeling code such as KIVA) can be obtained from Prof. Ron Matthews at rdmatt{at}mail.utexas.edu or Prof. DK Ezekoye at dezekoye{at}mail.utexas.edu. Fundamental experiments, engine experiments, and modeling tasks were used to help develop the railplug as a new ignitor for large bore natural gas engines. As the result of these studies, we developed a railplug that could extend the Lean Stability Limit (LSL) of an engine operating at full load on natural gas from {phi} = 0.59 for operation on spark plugs down to {phi} = 0.53 using railplugs with the same delivered energy (0.7 J). However, this delivered energy would rapidly wear out the spark plug. For a conventional delivered energy (<0.05 J), the LSL is {phi} = 0.63 for a spark plug. Further, using a permanent magnet to aid the plasma movement, the LSL was extended to {phi} = 0.54 for a railplug with a delivered energy of only 0.15 J/shot, a typical discharge energy for commercial capacitive discharge ignition systems. Here, it should be

  6. Electromagnetic Exhaust Valve Event Optimization for Enhancing Gasoline Engine Performance

    Directory of Open Access Journals (Sweden)

    Fan Xinyu

    2017-01-01

    Full Text Available Variable exhaust valve events have the potential to further improve the engine power output, fuel economy and decrease the NOX emissions. Based on the moving coil electromagnetic valve train applied to engine exhaust system, effects of variable exhaust valve events are analyzed in detail and the optimization approaches are carried out. Also with the fully variable intake and exhaust valve train, different internal EGR strategies can be achieved and the contrastive analyses are carried out between combustion chamber recirculation and exhaust port recirculation strategies at same operational condition. Results show that, the optimal exhaust valve opening motion can strengthen both power performance and fuel economy at engine part loads. And two principal EGR strategies are applied in a good combination under variable engine loads. At the engine speed of 2000 r/min, BMEP is about 0.3 MPa and with 30%~35% exhaust port recirculation rate, the BSFC and NOX emissions have decrease over 10% and 85% respectively compare with initial condition.

  7. Performance enhancement of electronic sensor through mask-less lithography

    KAUST Repository

    Nag, Anindya

    2016-03-30

    The escalating applications of miniaturized sensors have led the microelectronics industry to stay abreast with the precise micro-fabrication technologies. The following article describes a new technique for the fabrication of miniaturized interdigitated capacitive sensors that own highly sensitive and real-time detections capabilities. In standard lithographic procedure, the sensors are fabricated applying different photoresist materials that give rise to the variable characteristic profile of the fabricated product. Single crystal p-doped Silicon wafer was used as a substrate material due to its advantageous properties over Germanium. Heidelberg system was used for the maskless lithographic patterning of the new interdigital sensors on a silicon substrate. The process was carried out in a clean room in the absence of ultraviolet light at a fixed temperature. The fabricated sensors were used for inflammable gas sensing application. Electrochemical Impedance Spectroscopy was applied to read the resistive and capacitive impedance measured by the sensor. The results proclaimed that the fabricated sensors own better performance in LPG detection as compared to its commercial counterparts.

  8. Performance of green waste biocovers for enhancing methane oxidation.

    Science.gov (United States)

    Mei, Changgen; Yazdani, Ramin; Han, Byunghyun; Mostafid, M Erfan; Chanton, Jeff; VanderGheynst, Jean; Imhoff, Paul

    2015-05-01

    Green waste aged 2 and 24months, labeled "fresh" and "aged" green waste, respectively, were placed in biocover test cells and evaluated for their ability to oxidize methane (CH4) under high landfill gas loading over a 15-month testing period. These materials are less costly to produce than green waste compost, yet satisfied recommended respiration requirements for landfill compost covers. In field tests employing a novel gas tracer to correct for leakage, both green wastes oxidized CH4 at high rates during the first few months of operation - 140 and 200g/m(2)/day for aged and fresh green waste, respectively. Biocover performance degraded during the winter and spring, with significant CH4 generated from anaerobic regions in the 60-80cm thick biocovers. Concurrently, CH4 oxidation rates decreased. Two previously developed empirical models for moisture and temperature dependency of CH4 oxidation in soils were used to test their applicability to green waste. Models accounted for 68% and 79% of the observed seasonal variations in CH4 oxidation rates for aged green waste. Neither model could describe similar seasonal changes for the less stable fresh green waste. This is the first field application and evaluation of these empirical models using media with high organic matter. Given the difficulty of preventing undesired CH4 generation, green waste may not be a viable biocover material for many climates and landfill conditions. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Hull-form optimization of KSUEZMAX to enhance resistance performance

    Directory of Open Access Journals (Sweden)

    Jong-Heon Park

    2015-01-01

    Full Text Available This paper deploys optimization techniques to obtain the optimum hull form of KSUEZMAX at the conditions of full-load draft and design speed. The processes have been carried out using a RaPID-HOP program. The bow and the stern hull-forms are optimized separately without altering neither, and the resulting versions of the two are then combined. Objective functions are the minimum values of wave-making and viscous pressure resistance coefficients for the bow and stern. Parametric modification functions for the bow hull-form variation are SAC shape, section shape (U-Vtype, DLWL type, bulb shape (bulb height and size; and those for the stern are SAC and section shape (U-Vtype, DLWL type. WAVIS version 1.3 code is usedfor the potential and the viscous-flow solver. Prior to the optimization, a parametric study has been conducted to observe the effects of design parameters on the objective functions. SQP has been applied for the optimization algorithm. The model tests have been conducted at a towing tank to evaluate the resistance performance of the optimized hull-form. It has been noted that the optimized hull-form brings 2.4% and 6.8% reduction in total and residual resistance coefficients compared to those of the original hull-form. The propulsive efficiency increases by 2.0% and the delivered power is reduced 3.7%, whereas the propeller rotating speed increases slightly by 0.41 rpm.

  10. Engineered carbon nanotubes reinforced polymer composites for enhanced thermoelectric performance

    Science.gov (United States)

    Kiran, Raj; Kumar, Anuruddh; Chauhan, Vishal S.; Kumar, Rajeev; Vaish, Rahul

    2017-10-01

    Thermoelectric materials have attracted great attention from researchers because of their unique ability to convert thermal energy to electrical energy and vice versa. Based on the coupled theory of transport between heat and electricity in metals, we have carried out finite element simulations on carbon nanotube (CNT)/polyaniline (PANI) composites to compute effective Seebeck coefficients and figures of merit (FOMs). The present study focuses on the effect of interfacial electrical and thermal conductivities, the volume fraction of CNTs and their inclination on the effective electrical and thermal conductivities and thermoelectric performance. It is interesting to report that effective conductivities strongly depend on interfacial conductance in composites where CNTs are transverse to electrical current and heat flow. Interfaces with electrical and thermal conductance less than 103 S m‑2 and 107 W m‑2 K‑1 respectively isolate CNTs from the matrix. This reduces the effective properties, while the conductivities increase with the CNT content if interfacial conductance is more than these specified values. It was also established that the effective Seebeck coefficient and FOM increase with interfacial electrical conductance, while decreasing with an increase in interfacial thermal conductance. Additionally, the effect of inclination on the electrical and thermal conductivities of composites, the effective Seebeck coefficient and the FOM were analysed. It can be concluded from the study that the Seebeck coefficient and FOM of thermoelectric composites are increased if the CNTs are lying perpendicular to the heat and electrical current flow.

  11. The American Serialization of Lord Jim

    Directory of Open Access Journals (Sweden)

    Stephen Donovan

    2017-12-01

    Full Text Available This essay presents the discovery of the American serialization of Joseph Conrad’s Lord Jim in New York’s Evening Telegram in 1903. This ‘lost’ serialization, it argues, invites a new perspective on Conrad’s early career by foregrounding the role of newspaper serialization and syndication in establishing his literary standing. After surveying the principal differences in the respective reading experiences of the periodical versus the book, it concludes by proposing that the prominence of women among Conrad’s first audiences requires us to reassess the basis for his success in North America and elsewhere.

  12. Background instrumental music and serial recall.

    Science.gov (United States)

    Nittono, H

    1997-06-01

    Although speech and vocal music are consistently shown to impair serial recall for visually presented items, instrumental music does not always produce a significant disruption. This study investigated the features of instrumental music that would modulate the disruption in serial recall. 24 students were presented sequences of nine digits and required to recall the digits in order of presentation. Instrumental music as played either forward or backward during the task. Forward music caused significantly more disruption than did silence, whereas the reversed music did not. Some higher-order factor may be at work in the effect of background music on serial recall.

  13. Enhanced electrochemical performance of carbon quantum dots-polyaniline hybrid

    Science.gov (United States)

    Zhao, Zhichao; Xie, Yibing

    2017-01-01

    Carbon quantum dots-polyaniline (CQDs-PANI) hybrid was developed as supercapacitor electorde material by incorporating CQDs into PANI. PANI nanowires were grown vertically on carbon fiber substrate to form an interconnected network structure. Meanwhile, CQDs were uniformly distributed in the interior and on the surface of well-established net-like PANI nanowires. High specific capacitance of 738.3 F g-1 at 1.0 A g-1 was obtained for CQDs-PANI compared to that of 432.5 F g-1 for pure PANI. The capacitance retention after 1000 cycles of CQDs-PANI and PANI is 78.0% and 68.0% at 5.0 A g-1, respectively. The high capacitance and reasonable cycle stability were ascribed to the incorporation of CQDs into PANI, which improved the conductivity and alleviated the volume change of the CQDs-PANI electrode during the charge/discharge process. In addition, a flexible solid-state CQDs-PANI supercapacitor was constructed using carbon paper as current collector and polyvinyl alcohol gel electrolyte, exhibiting the stable capacitive performance at planar and bending state. The specific capacitance, energy and power density were determined to be 169.2 mF cm-2, 33.8 μWh cm-2 and 0.3 mW cm-2 at a potential window of 1.2 V and a current density of 1.0 mA cm-2. CQDs-PANI presented the promising application in flexible energy-related device.

  14. Enhanced propellant performance via environmentally friendly curable surface coating

    Directory of Open Access Journals (Sweden)

    Thelma Manning

    2017-06-01

    Full Text Available Surface coating of granular propellants is widely used in a multiplicity of propellants for small, medium and large caliber ammunition. All small caliber ball propellants exhibit burning progressivity due to application of effective deterrent coatings. Large perforated propellant grains have also begun utilizing plasticizing and impregnated deterrent coatings with the purpose of increasing charge weights for greater energy and velocity for the projectile. The deterrent coating and impregnation process utilizes volatile organic compounds (VOCs and hazardous air pollutants (HAPs which results in propellants that need to be forced air dried which impacts air quality. Propellants undergo temperature fluctuations during their life. Diffusion coefficients vary exponentially with variations in temperature. A small temperature increase can induce a faster migration, even over a short period of time, which can lead to large deviations in the concentration. This large concentration change in the ammunition becomes a safety or performance liability. The presence of both polymeric deterrents and nitroglycerin(NG in the nitrocellulose matrix and organic solvents leads to higher diffusion rates. This results in continued emissions of VOCs and HAPs. Conventional polymers tend to partition within the propellant matrix. In other words, localized mixing can occur between the polymer and underlying propellant. This is due to solvent induced softening of the polymer vehicle over the propellant grain. In effect this creates a path where migration can occur. Since nitrate esters, like NG, are relatively small, it can exude to the surface and create a highly unstable and dangerous situation for the warfighter. Curable polymers do not suffer from this partitioning due to “melting” because no VOC solvents are present. They remain surface coated. The small scale characterization testing, such as closed bomb testing, small scale sensitivity, thermal stability, and

  15. 40 CFR 51.351 - Enhanced I/M performance standard.

    Science.gov (United States)

    2010-07-01

    ... requirements are listed in § 51.371 of this subpart. (c) On-board diagnostics (OBD). For those areas required to implement an enhanced I/M program prior to the effective date of designation and classifications... enhanced I/M as a result of designation and classification under the 8-hour ozone standard, the performance...

  16. Adverse Health Consequences of Performance-Enhancing Drugs: An Endocrine Society Scientific Statement

    National Research Council Canada - National Science Library

    Pope, Harrison G; Wood, Ruth I; Rogol, Alan; Nyberg, Fred; Bowers, Larry; Bhasin, Shalender

    2014-01-01

    Despite the high prevalence of performance-enhancing drug (PED) use, media attention has focused almost entirely on PED use by elite athletes to illicitly gain a competitive advantage in sports, and not on the health risks of PEDs...

  17. Serial quantitative EEG among elderly subjects with delirium.

    Science.gov (United States)

    Jacobson, S A; Leuchter, A F; Walter, D O; Weiner, H

    1993-08-01

    Serial quantitative electroencephalographic (QEEG) studies were performed in 33 elderly delirious, demented, and control subjects to determine which QEEG variables were associated with changes in clinical state as measured by the Folstein Mini-mental State Examination (MMSE). Conventional EEGs and brain maps were independently rated by two electroencephalographers without knowledge of clinical diagnoses. Correlational analyses were performed using these ratings, along with numerical data from QEEG. In the delirium group (n = 15), changes in scores for the relative power map and changes in relative power in the alpha band had significant associations with changes in MMSE. In the dementia group (n = 10), changes in score for absolute power maps and changes in absolute power in the delta band had significant associations with changes in MMSE. In the control group, changes in MMSE over time were negligible. These findings have potential clinical utility in diagnosing delirium, and in providing a quantitative measure of its severity, which can be used serially.

  18. Examining the relationship between free recall and immediate serial recall: the serial nature of recall and the effect of test expectancy.

    Science.gov (United States)

    Bhatarah, Parveen; Ward, Geoff; Tan, Lydia

    2008-01-01

    In two experiments, we examined the relationship between free recall and immediate serial recall (ISR), using a within-subjects (Experiment 1) and a between-subjects (Experiment 2) design. In both experiments, participants read aloud lists of eight words and were precued or postcued to respond using free recall or ISR. The serial position curves were U-shaped for free recall and showed extended primacy effects with little or no recency for ISR, and there was little or no difference between recall for the precued and the postcued conditions. Critically, analyses of the output order showed that although the participants started their recall from different list positions in the two tasks, the degree to which subsequent recall was serial in a forward order was strikingly similar. We argue that recalling in a serial forward order is a general characteristic of memory and that performance on ISR and free recall is underpinned by common memory mechanisms.

  19. Chiropractic treatment and the enhancement of sport performance: a narrative literature review

    OpenAIRE

    Miners, Andrew L.

    2010-01-01

    A literature search and narrative review was carried out with the intent of determining the current level of knowledge regarding the chiropractic treatment of athletes for the purpose of sport performance enhancement. Of the fifty-nine relevant articles retrieved, only 7 articles of variable quality were obtained which specifically investigated/discussed chiropractic treatment and its involvement in sport performance enhancement. The role of the chiropractor in sport, unsubstantiated claims o...

  20. THE USE OF PERFORMANCE ENHANCING SWIMWEAR DURING AQUA THERAPY FOR CEREBRAL PALSY – A CASE STUDY

    OpenAIRE

    Kangas, Emmi-Sofia

    2016-01-01

    The purpose of the thesis was to study the effects of the use of performance enhancing swimwear on a client with Cerebral Palsy (CP). This was done by interviewing a client with Spastic Diplegic CP who uses performance enhancing swimwear during aqua therapy sessions with her physiotherapist. For additional insight about the use of the swimwear the physiotherapist was also interviewed. CP is the most common motor disability in childhood, primarily affecting motor control and movement coord...

  1. Contrast-enhanced ultrasound features of histologically proven focal nodular hyperplasia: diagnostic performance compared with contrast-enhanced CT.

    Science.gov (United States)

    Wang, Wei; Chen, Li-Da; Lu, Ming-De; Liu, Guang-Jian; Shen, Shun-Li; Xu, Zuo-Feng; Xie, Xiao-Yan; Wang, Yan; Zhou, Lu-Yao

    2013-09-01

    To investigate and compare contrast-enhanced ultrasound (CEUS) in the characterisation of histologically proven focal nodular hyperplasia (FNH) with contrast-enhanced computed tomography (CECT). CEUS was performed in 85 patients with 85 histologically proven FNHs. Enhancement, centrifugal filling, spoke-wheel arteries, feeding artery and central scarring were reviewed and correlated with lesion size or liver background. Independent factors for predicting FNH from other focal liver lesions (FLLs) were evaluated. Forty-seven FLLs with CECT were randomly selected for comparison of diagnostic performance with CEUS. Centrifugal filling was more common (P = 0.002) and the significant predictor (P = 0.003) in FNHs ≤3 cm. Lesion size or liver background has no significant influence on the detection rate of the spoke-wheel arteries and feeding artery (P > 0.05). Central scarring was found in 42.6 % of FNHs ≥3 cm (P = 0.000). The area under the ROC curve, sensitivity and specificity showed no significant differences between CEUS and CECT (P > 0.05), except that the sensitivity of CEUS was better for reader 1 (P = 0.041). CEUS is valuable in characterising centrifugal filling signs or spoke wheels in small FNHs and should be employed as the first-line imaging technique for diagnosis of FNH. • The confident diagnosis of focal nodular hyperplasia is important in liver imaging. • The centrifugal filling sign is useful for diagnosis of FNHs ≤3 cm. • Contrast-enhanced ultrasound and contrast-enhanced CT have similar diagnostic performance for FNH. • CEUS should be the first-line imaging technique for the diagnosis of FNH.

  2. Evidence for a specific impairment of serial order short-term memory in dyslexic children.

    Science.gov (United States)

    Martinez Perez, Trecy; Majerus, Steve; Mahot, Aline; Poncelet, Martine

    2012-05-01

    In order to better understand the nature of verbal short-term memory (STM) deficits in dyslexic children, the present study used the distinction between item and serial order retention capacities in STM tasks. According to recent STM models, storage of verbal item information depends very directly upon the richness of underlying phonological and semantic representations. On the other hand, storage of serial order information appears to reflect a language-independent system. Hence, if there is a fundamental STM deficit in dyslexia that is not to be explained only by the poor phonological processing abilities that characterize dyslexia, then difficulties in serial order STM should also be observed in dyslexic children. We administered tasks maximizing either serial order or item retention capacities to dyslexic children and reading age (RA) and chronological age (CA) matched controls. Dyslexic children performed significantly poorer than the CA controls on the item STM measure. Furthermore, the dyslexic group obtained inferior performance than both CA and RA control groups on the serial order STM measure. These findings highlight a severe impairment of STM for serial order information in dyslexia that cannot be reduced to a phonological processing impairment. Implications of serial order retention deficits for reading acquisition and dyslexia are discussed. Copyright © 2012 John Wiley & Sons, Ltd.

  3. Virtual reality paced serial assessment test for neuropsychological assessment of a military cohort.

    Science.gov (United States)

    Parsons, Thomas D; Courtney, Christopher; Rizzo, Albert A; Armstrong, Christina; Edwards, Joseph; Reger, Gregory

    2012-01-01

    The assessment and treatment of traumatic brain injury (TBI) has become a difficult challenge for the DoD medical health system. Clinical neuropsychologists are being asked to make statements regarding a soldier's functional skills, ability to return to active duty, and competence in tasks of community living. Given the increasing prevalence of blast injuries to the head, and the fact that many brain injuries may have no external marker of injury, there is need for researching innovative assessment methods in detecting blast-related brain injury. To address these issues, two virtual reality-based Paced Auditory/Visual Serial Addition Tests (PA/VSAT) were developed that involve the participant being immersed in a Virtual Middle Eastern City as serial addition stimuli are presented. This study is an initial validation of the VRPASAT and VRPVSAT as assessments of neurocognitive functioning. When compared to the paper-and-pencil version of the test, as well as the Automated Neuropsychological Assessment Metrics, the VRPASAT and VRPVSAT appear to have enhanced capacity for providing an indication of a participant's performance while immersed in a military relevant simulation.

  4. Efficient multitasking: parallel versus serial processing of multiple tasks

    Science.gov (United States)

    Fischer, Rico; Plessow, Franziska

    2015-01-01

    In the context of performance optimizations in multitasking, a central debate has unfolded in multitasking research around whether cognitive processes related to different tasks proceed only sequentially (one at a time), or can operate in parallel (simultaneously). This review features a discussion of theoretical considerations and empirical evidence regarding parallel versus serial task processing in multitasking. In addition, we highlight how methodological differences and theoretical conceptions determine the extent to which parallel processing in multitasking can be detected, to guide their employment in future research. Parallel and serial processing of multiple tasks are not mutually exclusive. Therefore, questions focusing exclusively on either task-processing mode are too simplified. We review empirical evidence and demonstrate that shifting between more parallel and more serial task processing critically depends on the conditions under which multiple tasks are performed. We conclude that efficient multitasking is reflected by the ability of individuals to adjust multitasking performance to environmental demands by flexibly shifting between different processing strategies of multiple task-component scheduling. PMID:26441742

  5. Efficient multitasking: parallel versus serial processing of multiple tasks.

    Science.gov (United States)

    Fischer, Rico; Plessow, Franziska

    2015-01-01

    In the context of performance optimizations in multitasking, a central debate has unfolded in multitasking research around whether cognitive processes related to different tasks proceed only sequentially (one at a time), or can operate in parallel (simultaneously). This review features a discussion of theoretical considerations and empirical evidence regarding parallel versus serial task processing in multitasking. In addition, we highlight how methodological differences and theoretical conceptions determine the extent to which parallel processing in multitasking can be detected, to guide their employment in future research. Parallel and serial processing of multiple tasks are not mutually exclusive. Therefore, questions focusing exclusively on either task-processing mode are too simplified. We review empirical evidence and demonstrate that shifting between more parallel and more serial task processing critically depends on the conditions under which multiple tasks are performed. We conclude that efficient multitasking is reflected by the ability of individuals to adjust multitasking performance to environmental demands by flexibly shifting between different processing strategies of multiple task-component scheduling.

  6. Administration of Dehydroepiandrosterone (DHEA) Enhances Visual-Spatial Performance in Post-Menopausal Women

    OpenAIRE

    Stangl, Bethany; Hirshman, Elliot; Verbalis, Joseph

    2011-01-01

    The current paper examines the effect of administering Dehydroepiandrosterone (DHEA) on visual-spatial performance in post-menopausal women (N=24, ages 55-80). The concurrent reduction of serum DHEA levels and visual-spatial performance in this population, coupled with the documented effects of DHEA’s androgenic metabolites on visual-spatial performance, suggest that DHEA administration may enhance visual-spatial performance. The current experiment used a double-blind placebo-controlled cross...

  7. Interfacing sensory input with motor output: does the control architecture converge to a serial process along a single channel?

    Science.gov (United States)

    van de Kamp, Cornelis; Gawthrop, Peter J; Gollee, Henrik; Lakie, Martin; Loram, Ian D

    2013-01-01

    Modular organization in control architecture may underlie the versatility of human motor control; but the nature of the interface relating sensory input through task-selection in the space of performance variables to control actions in the space of the elemental variables is currently unknown. Our central question is whether the control architecture converges to a serial process along a single channel? In discrete reaction time experiments, psychologists have firmly associated a serial single channel hypothesis with refractoriness and response selection [psychological refractory period (PRP)]. Recently, we developed a methodology and evidence identifying refractoriness in sustained control of an external single degree-of-freedom system. We hypothesize that multi-segmental whole-body control also shows refractoriness. Eight participants controlled their whole body to ensure a head marker tracked a target as fast and accurately as possible. Analysis showed enhanced delays in response to stimuli with close temporal proximity to the preceding stimulus. Consistent with our preceding work, this evidence is incompatible with control as a linear time invariant process. This evidence is consistent with a single-channel serial ballistic process within the intermittent control paradigm with an intermittent interval of around 0.5 s. A control architecture reproducing intentional human movement control must reproduce refractoriness. Intermittent control is designed to provide computational time for an online optimization process and is appropriate for flexible adaptive control. For human motor control we suggest that parallel sensory input converges to a serial, single channel process involving planning, selection, and temporal inhibition of alternative responses prior to low dimensional motor output. Such design could aid robots to reproduce the flexibility of human control.

  8. Evaluation of Serial Casting for Boys with Duchenne Muscular Dystrophy: A Case Report.

    Science.gov (United States)

    Carroll, Kate; de Valle, Katy; Kornberg, Andrew; Ryan, Monique; Kennedy, Rachel

    2017-03-16

    To report the effects of below-knee serial casting in two boys with Duchenne muscular dystrophy who presented with well-preserved strength and calf shortening. Bilateral below-knee serial casts were applied over two weeks with follow-up of daily stretching and wearing of customized night splints. Outcome measures were performed at baseline, 1, 3, 6, and 12 months post-casting. These included measures of calf length, leg strength, motor function, endurance, and spatio-temporal gait parameters. Both boys completed serial casting with gains in muscle length. No adverse effects on strength or motor function were observed over a 12-month follow-up period.

  9. Peer groups and operational cycle enhancements to the performance indicator report

    Energy Technology Data Exchange (ETDEWEB)

    Stromberg, H.M.; DeHaan, M.S.; Gentillon, C.D.; Wilson, G.E. (EG and G Idaho, Inc., Idaho Falls, ID (United States)); Vanden Heuvel, L.N. (Oak Ridge National Lab., TN (United States))

    1992-12-01

    Accurate performance evaluation and plant trending by the performance indicator program are integral parts of monitoring the operation of commercial nuclear power plants. The presentations of the NRC/AEOD performance indicator program have undergone a number of enhancements. The diversity of the commercial nuclear plants, coupled with continued improvements in the performance indicator program, has resulted in the evaluation of plants in logical peer groups and highlighted the need to evaluate the impact of plant operational conditions on the performance indicators. These enhancements allow a more-meaningful evaluation of operating commercial nuclear power plant performance. This report proposes methods to enhance the presentation of the performance indicator data by analyzing the data in logical peer groups and displaying the performance indicator data based on the operational status of the plants. Previously, preliminary development of the operational cycle displays of the performance indicator data was documented. This report extends the earlier findings and presents the continued development of the peer groups and operational cycle trend and deviation data and displays. This report describes the peer groups and enhanced PI data presentations by considering the operational cycle phase breakdowns, calculation methods, and presentation methods.

  10. Simulating and stimulating performance: introducing distributed simulation to enhance musical learning and performance.

    Science.gov (United States)

    Williamon, Aaron; Aufegger, Lisa; Eiholzer, Hubert

    2014-01-01

    Musicians typically rehearse far away from their audiences and in practice rooms that differ significantly from the concert venues in which they aspire to perform. Due to the high costs and inaccessibility of such venues, much current international music training lacks repeated exposure to realistic performance situations, with students learning all too late (or not at all) how to manage performance stress and the demands of their audiences. Virtual environments have been shown to be an effective training tool in the fields of medicine and sport, offering practitioners access to real-life performance scenarios but with lower risk of negative evaluation and outcomes. The aim of this research was to design and test the efficacy of simulated performance environments in which conditions of "real" performance could be recreated. Advanced violin students (n = 11) were recruited to perform in two simulations: a solo recital with a small virtual audience and an audition situation with three "expert" virtual judges. Each simulation contained back-stage and on-stage areas, life-sized interactive virtual observers, and pre- and post-performance protocols designed to match those found at leading international performance venues. Participants completed a questionnaire on their experiences of using the simulations. Results show that both simulated environments offered realistic experience of performance contexts and were rated particularly useful for developing performance skills. For a subset of 7 violinists, state anxiety and electrocardiographic data were collected during the simulated audition and an actual audition with real judges. Results display comparable levels of reported state anxiety and patterns of heart rate variability in both situations, suggesting that responses to the simulated audition closely approximate those of a real audition. The findings are discussed in relation to their implications, both generalizable and individual-specific, for performance training.

  11. Simulating and stimulating performance: Introducing distributed simulation to enhance musical learning and performance

    Directory of Open Access Journals (Sweden)

    Aaron eWilliamon

    2014-02-01

    Full Text Available Musicians typically rehearse far away from their audiences and in practice rooms that differ significantly from the concert venues in which they aspire to perform. Due to the high costs and inaccessibility of such venues, much current international music training lacks repeated exposure to realistic performance situations, with students learning all too late (or not at all how to manage performance stress and the demands of their audiences. Virtual environments have been shown to be an effective training tool in the fields of medicine and sport, offering practitioners access to real-life performance scenarios but with lower risk of negative evaluation and outcomes. The aim of this research was to design and test the efficacy of simulated performance environments in which conditions of real performance could be recreated. Advanced violin students (n=11 were recruited to perform in two simulations: a solo recital with a small virtual audience and an audition situation with three expert virtual judges. Each simulation contained back-stage and on-stage areas, life-sized interactive virtual observers, and pre- and post-performance protocols designed to match those found at leading international performance venues. Participants completed a questionnaire on their experiences of using the simulations. Results show that both simulated environments offered realistic experience of performance contexts and were rated particularly useful for developing performance skills. For a subset of 7 violinists, state anxiety and electrocardiographic data were collected during the simulated audition and an actual audition with real judges. Results display comparable levels of reported state anxiety and patterns of heart rate variability in both situations, suggesting that responses to the simulated audition closely approximate those of a real audition. The findings are discussed in relation to their implications, both generalizable and individual-specific, for

  12. Serial CT scans of cerebral hypoxia due to prolonged status epilepticus

    Energy Technology Data Exchange (ETDEWEB)

    Saiwai, Shigeo; Matsumura, Yasumasa; Tamaoka, Koichi; Fukuda, Teruo; Miyamoto, Takeshi (Kobe Central Municipal Hospital, Kobe (Japan))

    1983-04-01

    Serial computed tomography (CT) scans of 5 infants with status epilepticus were reviewed. Four out of the 5 infants fortunately had CT scans before status epilepticus because of a convulsion. There was a diffuse and mild low density in the hemisphere, with small ventricles and tight sulci (brain swelling) at 1 to 2 days after ictus. Thereafter, a diffuse low density became apparent except for the cerebellum, the brain stem, the thalamus, and the basal ganglia. Two to 4 weeks after ictus, a localized, mottled low density was demonstrated on the cerebral mantle and atrophic changes became progressively clear. In 3 cases, no abnormal enhancement was elicited on contrast CT scans performed between 5 to 16 days after status epilepticus. We discussed the possible pathophysiological aspects of the brain damage due to ''prolonged status epilepticus.''

  13. Comparison of the Prevalence of Psychiatric Disorders in Performance-Enhancing Drug Users and Nonuser Bodybuilders.

    Science.gov (United States)

    Ostovar, Afshin; Haerinejad, Mohammad Javad; Akbarzadeh, Samad; Keshavarz, Mojtaba

    2017-10-01

    Objective: The present study aimed at comparing the prevalence of major psychiatric disorders including major depressive disorder, bipolar disorder, schizophrenia, and generalized anxiety disorder between performance-enhancing drug users and nonuser bodybuilders. Moreover, the prevalence of major psychiatric disorders in bodybuilders was also reported. Method: In this study, 453 athletes were recruited from Bushehr bodybuilding gyms from February to May 2015. A structured questionnaire was used to collect the participants' information, including demographic characteristics, sports' status and performance-enhancing drug use. According to the condition of performance-enhancing drug use, the participants were divided into current users, non-current users, and nonusers. The psychiatric status of the participants was evaluated using DSM-IV diagnostic criteria for major depressive disorder, bipolar disorder, generalized anxiety disorder, and schizophrenia. We also asked about the acute psychotic disturbances after using performance-enhancing drugs, alcohol use, and history of aggressive behavior in bodybuilders. Data were analyzed using one-way analysis of variance and chi-square tests. Results: Prevalence of major depressive disorder, bipolar disorder, schizophrenia, generalized anxiety disorder, and the overall prevalence of psychiatric disorders in the bodybuilders was 19.7%, 3.8%, 1.5%, 16.6%, and 26.7%, respectively. After using performance-enhancing drugs, 33% of the bodybuilders had experienced acute psychological disturbances. There were no significant differences between current, non-current, and nonuser bodybuilding athletes in the measured psychiatric disorders. Conclusion: Prevalence of psychiatric disorders was not significantly different in performance-enhancing drug users and nonusers. Thus, it can be concluded that performance-enhancing drugs do not increase the risk of psychiatric disorders in bodybuilders.

  14. Comparison of the Prevalence of Psychiatric Disorders in Performance-Enhancing Drug Users and Nonuser Bodybuilders

    Directory of Open Access Journals (Sweden)

    Afshin Ostovar

    2017-10-01

    Full Text Available Objective: The present study aimed at comparing the prevalence of major psychiatric disorders including major depressive disorder, bipolar disorder, schizophrenia, and generalized anxiety disorder between performance-enhancing drug users and nonuser bodybuilders. Moreover, the prevalence of major psychiatric disorders in bodybuilders was also reported.Method: In this study, 453 athletes were recruited from Bushehr bodybuilding gyms from February to May 2015. A structured questionnaire was used to collect the participants’ information, including demographic characteristics, sports’ status and performance-enhancing drug use. According to the condition of performance-enhancing drug use, the participants were divided into current users, non-current users, and nonusers. The psychiatric status of the participants was evaluated using DSM-IV diagnostic criteria for major depressive disorder, bipolar disorder, generalized anxiety disorder, and schizophrenia. We also asked about the acute psychotic disturbances after using performance-enhancing drugs, alcohol use, and history of aggressive behavior in bodybuilders. Data were analyzed using one-way analysis of variance and chi-square tests.Results: Prevalence of major depressive disorder, bipolar disorder, schizophrenia, generalized anxiety disorder, and the overall prevalence of psychiatric disorders in the bodybuilders was 19.7%, 3.8%, 1.5%, 16.6%, and 26.7%, respectively. After using performance-enhancing drugs, 33% of the bodybuilders had experienced acute psychological disturbances. There were no significant differences between current, non-current, and nonuser bodybuilding athletes in the measured psychiatric disorders.Conclusion: Prevalence of psychiatric disorders was not significantly different in performance-enhancing drug users and nonusers. Thus, it can be concluded that performance-enhancing drugs do not increase the risk of psychiatric disorders in bodybuilders.

  15. Social psychological determinants of the use of performance-enhancing drugs by gym users.

    Science.gov (United States)

    Wiefferink, C H; Detmar, S B; Coumans, B; Vogels, T; Paulussen, T G W

    2008-02-01

    The aim of this study is to identify the social psychological determinants of the use of performance-enhancing drugs by gym users who practice bodybuilding, fitness, powerlifting or combat sports. In this questionnaire-based study, 144 respondents answered questions on their actual use and intention to use such drugs and also on their background characteristics and beliefs, such as their attitudes, social influences and self-efficacy. While all social psychological determinants correlated with intention to use these drugs, the most important predictors were personal norms, beliefs about performance outcomes and the perceived behavior of others. Non-users held more restrictive norms about using performance-enhancing drugs, were less optimistic about the performance-enhancing outcomes and believed that fewer significant others used performance-enhancing drugs than users and ex-users. The results of this study indicate that users attribute advantages to performance-enhancing drugs and are inclined to overlook the risks of using them. Preventive interventions should focus on influencing personal norms and social processes.

  16. HEAT TRANSFER EVALUATION OF HFC-236EA WITH HIGH PERFORMANCE ENHANCED TUBES IN CONDENSATION AND EVAPORATION

    Science.gov (United States)

    The report gives results of an evaluation of the heat transfer performance of pure hydrofluorocarbon (HFC)-236ea for high performance enhanced tubes which had not been previously used in Navy shipboard chillers. Shell-side heat transfer coefficient data are presented for condensa...

  17. Enhancing Self-Efficacy and Performance: An Experimental Comparison of Psychological Techniques

    Science.gov (United States)

    Wright, Bradley James; O'Halloran, Paul Daniel; Stukas, Arthur Anthony

    2016-01-01

    Purpose: We assessed how 6 psychological performance enhancement techniques (PETs) differentially improved self-efficacy (SE) and skill performance. We also assessed whether vicarious experiences and verbal persuasion as posited sources of SE (Bandura, 1982) were supported and, further, if the effects of the 6 PETs remained after controlling for…

  18. Using Technology-Enhanced, Cooperative, Group-Project Learning for Student Comprehension and Academic Performance

    Science.gov (United States)

    Tlhoaele, Malefyane; Suhre, Cor; Hofman, Adriaan

    2016-01-01

    Cooperative learning may improve students' motivation, understanding of course concepts, and academic performance. This study therefore enhanced a cooperative, group-project learning technique with technology resources to determine whether doing so improved students' deep learning and performance. A sample of 118 engineering students, randomly…

  19. Context and meter enhance long-range planning in music performance

    Directory of Open Access Journals (Sweden)

    Brian eMathias

    2015-01-01

    Full Text Available Neural responses demonstrate evidence of resonance, or oscillation, during the production of periodic auditory events. Music contains periodic auditory events that give rise to a sense of beat, which in turn generates a sense of meter on the basis of multiple periodicities. Metrical hierarchies may aid memory for music by facilitating similarity-based associations among sequence events at different periodic distances that unfold in longer contexts. A fundamental question is how metrical associations arising from a musical context influence memory during music performance. Longer contexts may facilitate metrical associations at higher hierarchical levels more than shorter contexts, a prediction of the range model, a formal model of planning processes in music performance (Palmer and Pfordresher, 2003; Pfordresher et al., 2007. Serial ordering errors, in which intended sequence events are produced in incorrect sequence positions, were measured as skilled pianists performed musical pieces that contained excerpts embedded in long or short musical contexts. Pitch errors arose from metrically similar positions and further sequential distances more often when the excerpt was embedded in long contexts compared to short contexts. Musicians’ keystroke intensities and error rates also revealed influences of metrical hierarchies, which differed for performances in long and short contexts. The range model accounted for contextual effects and provided better fits to empirical findings when metrical associations between sequence events were included. Longer sequence contexts may facilitate planning during sequence production by increasing conceptual similarity between hierarchically associated events. These findings are consistent with the notion that neural oscillations at multiple periodicities may strengthen metrical associations across sequence events during planning.

  20. Context and meter enhance long-range planning in music performance.

    Science.gov (United States)

    Mathias, Brian; Pfordresher, Peter Q; Palmer, Caroline

    2014-01-01

    Neural responses demonstrate evidence of resonance, or oscillation, during the production of periodic auditory events. Music contains periodic auditory events that give rise to a sense of beat, which in turn generates a sense of meter on the basis of multiple periodicities. Metrical hierarchies may aid memory for music by facilitating similarity-based associations among sequence events at different periodic distances that unfold in longer contexts. A fundamental question is how metrical associations arising from a musical context influence memory during music performance. Longer contexts may facilitate metrical associations at higher hierarchical levels more than shorter contexts, a prediction of the range model, a formal model of planning processes in music performance (Palmer and Pfordresher, 2003; Pfordresher et al., 2007). Serial ordering errors, in which intended sequence events are produced in incorrect sequence positions, were measured as skilled pianists performed musical pieces that contained excerpts embedded in long or short musical contexts. Pitch errors arose from metrically similar positions and further sequential distances more often when the excerpt was embedded in long contexts compared to short contexts. Musicians' keystroke intensities and error rates also revealed influences of metrical hierarchies, which differed for performances in long and short contexts. The range model accounted for contextual effects and provided better fits to empirical findings when metrical associations between sequence events were included. Longer sequence contexts may facilitate planning during sequence production by increasing conceptual similarity between hierarchically associated events. These findings are consistent with the notion that neural oscillations at multiple periodicities may strengthen metrical associations across sequence events during planning.

  1. Lipidic cubic phase serial millisecond crystallography using synchrotron radiation

    Directory of Open Access Journals (Sweden)

    Przemyslaw Nogly

    2015-03-01

    Full Text Available Lipidic cubic phases (LCPs have emerged as successful matrixes for the crystallization of membrane proteins. Moreover, the viscous LCP also provides a highly effective delivery medium for serial femtosecond crystallography (SFX at X-ray free-electron lasers (XFELs. Here, the adaptation of this technology to perform serial millisecond crystallography (SMX at more widely available synchrotron microfocus beamlines is described. Compared with conventional microcrystallography, LCP-SMX eliminates the need for difficult handling of individual crystals and allows for data collection at room temperature. The technology is demonstrated by solving a structure of the light-driven proton-pump bacteriorhodopsin (bR at a resolution of 2.4 Å. The room-temperature structure of bR is very similar to previous cryogenic structures but shows small yet distinct differences in the retinal ligand and proton-transfer pathway.

  2. Disentangling the Impact of Control-Enhancing Mechanisms on Firm Performance

    DEFF Research Database (Denmark)

    Zattoni, Alessandro; Pedersen, Torben

    2011-01-01

    shareholders to expropriate minority shareholders. The aim of this article is to contribute to the current debate investigating the implications of these control-enhancing mechanisms on firm performance. To reach this purpose, we collected ownership data on the (100) largest listed companies per capitalization...... in five European countries (i.e. France, Germany, Italy, Spain, and the UK). Then we tested the consequences of control-enhancing mechanisms for firm performance using 2SLS regression models. Our results show that (i) mechanisms that lock-in control do have a direct and negative impact on firm performance......, and (ii) the negative impact on firm performance of mechanisms aimed at enhancing control by leveraging voting power is mediated by the divergence in voting and cash flow rights....

  3. The Effect of Concurrent Semantic Categorization on Delayed Serial Recall

    Science.gov (United States)

    Acheson, Daniel J.; MacDonald, Maryellen C.; Postle, Bradley R.

    2010-01-01

    The influence of semantic processing on the serial ordering of items in short-term memory was explored using a novel dual-task paradigm. Subjects engaged in two picture judgment tasks while simultaneously performing delayed serial recall. List material varied in the presence of phonological overlap (Experiments 1 and 2) and in semantic content (concrete words in Experiment 1 and 3; nonwords in Experiments 2 and 3). Picture judgments varied in the extent to which they required accessing visual semantic information (i.e., semantic categorization and line orientation judgments). Results showed that, relative to line orientation judgments, engaging in semantic categorization judgments increased the proportion of item ordering errors for concrete lists but did not affect error proportions for nonword lists. Furthermore, although more ordering errors were observed for phonologically similar relative to dissimilar lists, no interactions were observed between the phonological overlap and picture judgment task manipulations. These results thus demonstrate that lexical-semantic representations can affect the serial ordering of items in short-term memory. Furthermore, the dual-task paradigm provides a new method for examining when and how semantic representations affect memory performance. PMID:21058880

  4. Contrast-enhanced ultrasound features of histologically proven focal nodular hyperplasia: diagnostic performance compared with contrast-enhanced CT

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Wei; Chen, Li-Da; Liu, Guang-Jian; Xu, Zuo-Feng; Xie, Xiao-Yan; Wang, Yan; Zhou, Lu-Yao [The First Affiliated Hospital of Sun Yat-Sen University Institute of Diagnostic and Interventional Ultrasound, Sun Yat-Sen University, Department of Medical Ultrasonics, Guangzhou (China); Lu, Ming-De [The First Affiliated Hospital of Sun Yat-Sen University Institute of Diagnostic and Interventional Ultrasound, Sun Yat-Sen University, Department of Medical Ultrasonics, Guangzhou (China); The First Affiliated Hospital of Sun Yat-Sen University, Department of Hepatobiliary Surgery, Guangzhou (China); Shen, Shun-Li [The First Affiliated Hospital of Sun Yat-Sen University, Department of Hepatobiliary Surgery, Guangzhou (China)

    2013-09-15

    To investigate and compare contrast-enhanced ultrasound (CEUS) in the characterisation of histologically proven focal nodular hyperplasia (FNH) with contrast-enhanced computed tomography (CECT). CEUS was performed in 85 patients with 85 histologically proven FNHs. Enhancement, centrifugal filling, spoke-wheel arteries, feeding artery and central scarring were reviewed and correlated with lesion size or liver background. Independent factors for predicting FNH from other focal liver lesions (FLLs) were evaluated. Forty-seven FLLs with CECT were randomly selected for comparison of diagnostic performance with CEUS. Centrifugal filling was more common (P = 0.002) and the significant predictor (P = 0.003) in FNHs {<=}3 cm. Lesion size or liver background has no significant influence on the detection rate of the spoke-wheel arteries and feeding artery (P > 0.05). Central scarring was found in 42.6 % of FNHs {>=}3 cm (P = 0.000). The area under the ROC curve, sensitivity and specificity showed no significant differences between CEUS and CECT (P > 0.05), except that the sensitivity of CEUS was better for reader 1 (P = 0.041). CEUS is valuable in characterising centrifugal filling signs or spoke wheels in small FNHs and should be employed as the first-line imaging technique for diagnosis of FNH. (orig.)

  5. POSSIBILITIES OF INCREASING EFFICIENCY WITHIN SERIAL PRODUCTION MANAGEMENT

    Directory of Open Access Journals (Sweden)

    CODRUŢA DURA

    2010-01-01

    Full Text Available Under the impact of transition to the new post-industrial society, massproduction recently faced the most numerous difficulties. They are caused by turbulences in theexternal environment in which companies operate, manifested in particular by enhancing thedynamism of markets and by deep changes in the structure of consumers’ demands. In thiscontext, specialized literature records the concerns for increasing the efficiency and flexibilityof products, elements involving radical changes of management and manufacturingtechnologies methods. Given these issues, the paper approaches two separate ways to improvethe management of serial production: increasing economic efficiency by optimizing the size ofbatches and flexible production systems by implementing techniques to reduce the change-overtime.

  6. Enhanced photoelectrochemical water splitting performance using morphology-controlled BiVO4 with W doping

    Directory of Open Access Journals (Sweden)

    Xin Zhao

    2017-12-01

    Full Text Available Nanostructures exhibit numerous merits to improve the efficiency in solar-to-energy conversion. These include shortened carrier collection pathways, an increased volume ratio between depletion layer and bulk, enhanced light capture due to multiple light scattering in nanostructures, and a high surface area for photochemical conversion reactions. In this study, we describe the synthesis of morphology-controlled W-doped BiVO4 by simply tuning the solvent ratio in precursor solutions. Planar and porous W-doped BiVO4 thin films were prepared and compared. The porous film, which exhibits increased surface area and enhanced light absorption, has displayed enhanced charge separation and interfacial charge injection. Our quantitative analysis showed an enhancement of about 50% of the photoelectrochemical performance for the porous structure compared to the planar structure. This enhancement is attributed to improved light absorption (13% increase, charge separation (14% increase, and interfacial charge injection (20% increase.

  7. Performance enhancement in the workplace: why and when healthy individuals should disclose their reliance on pharmaceutical cognitive enhancers.

    Science.gov (United States)

    Garasic, Mirko D; Lavazza, Andrea

    2015-01-01

    The use of pharmaceuticals cognitive enhancers (PCE) has been stirring growing interest, not only in the scientific domain but also in the popular media, and has probably had some increase recently in academic, professional and military quarters. So this phenomenon is deemed as a normal procedure aimed at improving the performance of an individual as well as the overall standards of an organization. Although the vast majority of countries have some kind of restrictions to reduce the wide non-medical usage of PCE, these can be overcome quite easily. In arguing for our explicit claim that, in many contexts, the use of cognitive enhancers should be disclosed-as a moral and socially relevant duty-we maintain that PCE present typical, or at least not rare, properties. The features are the following: (a) the enhancer has acute and/or chronic effects. In the first case, shortly after taking the drug the performance is significantly better than average; in the second case, there is a growing or lasting effect, which, however, is poised to diminish when one stops taking the drug; (b) those effects are significant (there is a difference in the outcome considered between taking and not taking the drug) and sometimes dramatic; and (c) a third feature, not directly related to enhancers as such, is their varying safety, availability, and legal permissibility, which might either induce people to take them or refrain them from doing so. We will consider the issue of fairness due to "unenhanced" people as well as the potentially dysfunctional social consequences of an undisclosed PCE use.

  8. Broad ion beam serial section tomography

    Energy Technology Data Exchange (ETDEWEB)

    Winiarski, B., E-mail: b.winiarski@manchester.ac.uk [School of Materials, University of Manchester, Manchester M13 9PL (United Kingdom); Materials Division, National Physical Laboratory, Teddington TW11 0LW (United Kingdom); Gholinia, A. [School of Materials, University of Manchester, Manchester M13 9PL (United Kingdom); Mingard, K.; Gee, M. [Materials Division, National Physical Laboratory, Teddington TW11 0LW (United Kingdom); Thompson, G.E.; Withers, P.J. [School of Materials, University of Manchester, Manchester M13 9PL (United Kingdom)

    2017-01-15

    Here we examine the potential of serial Broad Ion Beam (BIB) Ar{sup +} ion polishing as an advanced serial section tomography (SST) technique for destructive 3D material characterisation for collecting data from volumes with lateral dimensions significantly greater than 100 µm and potentially over millimetre sized areas. Further, the associated low level of damage introduced makes BIB milling very well suited to 3D EBSD acquisition with very high indexing rates. Block face serial sectioning data registration schemes usually assume that the data comprises a series of parallel, planar slices. We quantify the variations in slice thickness and parallelity which can arise when using BIB systems comparing Gatan PECS and Ilion BIB systems for large volume serial sectioning and 3D-EBSD data acquisition. As a test case we obtain 3D morphologies and grain orientations for both phases of a WC-11%wt. Co hardmetal. In our case we have carried out the data acquisition through the manual transfer of the sample between SEM and BIB which is a very slow process (1–2 slice per day), however forthcoming automated procedures will markedly speed up the process. We show that irrespective of the sectioning method raw large area 2D-EBSD maps are affected by distortions and artefacts which affect 3D-EBSD such that quantitative analyses and visualisation can give misleading and erroneous results. Addressing and correcting these issues will offer real benefits when large area (millimetre sized) automated serial section BIBS is developed. - Highlights: • In this work we examine how microstructures can be reconstructed in three-dimensions (3D) by serial argon broad ion beam (BIB) milling, enabling much larger volumes (>250×250×100µm{sup 3}) to be acquired than by serial section focused ion beam-scanning electron microscopy (FIB-SEM). • The associated low level of damage introduced makes BIB milling very well suited to 3D-EBSD acquisition with very high indexing rates. • We explore

  9. Visual search performance of patients with vision impairment: Effect of JPEG image enhancement

    Science.gov (United States)

    Luo, Gang; Satgunam, PremNandhini; Peli, Eli

    2012-01-01

    Purpose To measure natural image search performance in patients with central vision impairment. To evaluate the performance effect for a JPEG based image enhancement technique using the visual search task. Method 150 JPEG images were presented on a touch screen monitor in either an enhanced or original version to 19 patients (visual acuity 0.4 to 1.2 logMAR, 6/15 to 6/90, 20/50 to 20/300) and 7 normally sighted controls (visual acuity −0.12 to 0.1 logMAR, 6/4.5 to 6/7.5, 20/15 to 20/25). Each image fell into one of three categories: faces, indoors, and collections. The enhancement was realized by moderately boosting a mid-range spatial frequency band in the discrete cosine transform (DCT) coefficients of the image luminance component. Participants pointed to an object in a picture that matched a given target displayed at the upper-left corner of the monitor. Search performance was quantified by the percentage of correct responses, the median search time of correct responses, and an “integrated performance” measure – the area under the curve of cumulative correct response rate over search time. Results Patients were able to perform the search tasks but their performance was substantially worse than the controls. Search performances for the 3 image categories were significantly different (p≤0.001) for all the participants, with searching for faces being the most difficult. When search time and correct response were analyzed separately, the effect of enhancement led to increase in one measure but decrease in another for many patients. Using the integrated performance, it was found that search performance declined with decrease in acuity (p=0.005). An improvement with enhancement was found mainly for the patients whose acuity ranged from 0.4 to 0.8 logMAR (6/15 to 6/38, 20/50 to 20/125). Enhancement conferred a small but significant improvement in integrated performance for indoor and collection images (p=0.025) in the patients. Conclusion Search performance

  10. INFORMATION TECHNOLOGY FOR ENHANCING NGOS’ PERFORMANCE IN THE KINGDOM OF BAHRAIN

    OpenAIRE

    Jaflah Al-Ammary; Sharifa Hamad

    2012-01-01

    The current research aims to investigate the situation of the NGOs in the Kingdom of Bahrain from many aspects: types of IT adopted, reasons behind adopting IT, obstacles to adopting IT, perception of the impact of adopting IT to enhance organizational performance, and perception of the importance of using the Internet and web-based technology in enhancing NGOs’ organization services. Based on the investigation, a framework for adopting IT by NGOs in the Kingdom of Bahrain was developed. The ...

  11. [The serial murder: a few theoretical perspectives].

    Science.gov (United States)

    Leistedt, S; Linkowski, P

    2011-01-01

    Despite numbers of publications and effort to try to establish the definition, the classification, the epidemiology, the clinical aspects and the psychopathology of serial killers, a universal consensus seems to say the least. Crime, though reduced in some countries, appears to impact more and more consistent worldwide, generating controversial ideas and a multitude of possible explanations. The serial killer usually presents as a caucasian man, aged between 20 and 40 years, often embedded socially and in his family, but with serious psychiatric, personal and especially family history. Usually acting alone, the serial killer plans a crime well in advance, but sometimes within the scope of impulsivity for a minority, the victim not being previously selected. In the latter case, an actual mental illness like psychosis is found. It is clear from numerous psychopathological studies conducted so far that most serial killers are defined as psychopathic sexual sadists, whose childhood was difficult, if not flouted, punctuated by physical and psychological violence situations. In addition, pervasive fantasies combined with thoughts of death, sex and violence are as much in common with the original acts of which they are the instigators. Beyond a relentless media that is constantly watering the public with stories and pictures depicting them as such, serial killers remain an enigma. We can therefore attempt to answer the various questions raised by this phenomenon, the way these people operate and how we can curb the rise, thanks to the neurobiological and neurophysiological approaches that science offers us.

  12. Underestimated effects of sediments on enhanced startup performance of biofilm systems for polluted source water pretreatment.

    Science.gov (United States)

    Lv, Zheng-Hui; Wang, Jing; Yang, Guang-Feng; Feng, Li-Juan; Mu, Jun; Zhu, Liang; Xu, Xiang-Yang

    2018-02-01

    In order to evaluate the enhancement mechanisms of enhanced startup performance in biofilm systems for polluted source water pretreatment, three lab-scale reactors with elastic stereo media (ESM) were operated under different enhanced sediment and hydraulic agitation conditions. It is interesting to found the previously underestimated or overlooked effects of sediment on the enhancement of pollutants removal performance and enrichment of functional bacteria in biofilm systems. The maximum NH 4 + -N removal rate of 0.35 mg L -1 h -1 in sediment enhanced condition was 2.19 times of that in control reactor. Sediment contributed to 42.0-56.5% of NH 4 + -N removal and 15.4-41.2% of total nitrogen removal in different reactors under different operation conditions. The enhanced hydraulic agitation with sediment further improved the operation performance and accumulation of functional bacteria. Generally, Proteobacteria (48.9-52.1%), Bacteroidetes (18.9-20.8%) and Actinobacteria (15.7-18.5%) were dominant in both sediment and ESM bioiflm at  phylum level. The potentially functional bacteria found in sediment and ESM biofilm samples with some functional bacteria mainly presented in sediment samples only (e.g., Genera Bacillus and Lactococcus of Firmicutes phylum) may commonly contribute to the removal of nitrogen and organics.

  13. Performance Enhancement of Distribution Network with DG Integration Using Modified PSO Algorithm

    Directory of Open Access Journals (Sweden)

    Ramadoni Syahputra

    2016-03-01

    Full Text Available This paper addresses performance enhancement of distribution network with distributed generator (DG integration using modified particle swarm optimization (PSO algorithm. The effort of performance enhancement is done by using optimization of distribution network configuration. The objective of the optimization is minimizing active power loss and improving voltage profile while the distribution network is maintained in the radial structure. In this study, configuration optimization method is based on a modified PSO algorithm. The method has been tested in an IEEE model of 33-bus radial distribution network test system and a reallife radial distribution network of 60-bus Bantul distribution system, Indonesia. The simulation results show the importance of reconfiguring the network for enhancing the distribution network performance in the presence of DG.

  14. [Investigation of team processes that enhance team performance in business organization].

    Science.gov (United States)

    Nawata, Kengo; Yamaguchi, Hiroyuki; Hatano, Toru; Aoshima, Mika

    2015-02-01

    Many researchers have suggested team processes that enhance team performance. However, past team process models were based on crew team, whose all team members perform an indivisible temporary task. These models may be inapplicable business teams, whose individual members perform middle- and long-term tasks assigned to individual members. This study modified the teamwork model of Dickinson and McIntyre (1997) and aimed to demonstrate a whole team process that enhances the performance of business teams. We surveyed five companies (member N = 1,400, team N = 161) and investigated team-level-processes. Results showed that there were two sides of team processes: "communication" and "collaboration to achieve a goal." Team processes in which communication enhanced collaboration improved team performance with regard to all aspects of the quantitative objective index (e.g., current income and number of sales), supervisor rating, and self-rating measurements. On the basis of these results, we discuss the entire process by which teamwork enhances team performance in business organizations.

  15. Foundation and perspectives of the use of plant extracts as performance enhancers in broilers

    Directory of Open Access Journals (Sweden)

    PV Rizzo

    2008-12-01

    Full Text Available Feed is responsible for about 70% of broilers production costs, leading to an increasing number of studies on alternative dietary products that benefit bird performance and lower production costs. Since the 1950s, antimicrobial additives are the most frequently used performance enhancers in animal production and their positive results are observed even in high-challenge conditions. Since the 1990s, due to the ban of the use of some antibiotics as growth promoters and the growing trend of the public to consume natural products, plant extracts have been researched as alternatives to antibiotic growth promoters. The first study that evaluated the antibacterial activities of plant extracts was carried out in 1881; however, they started to be used as flavor enhancers only during the next decades. With the emergence of antibiotics in the 1950s, the use of plant extracts as antimicrobial agents almost disappeared. There are several studies in literature assessing the use of plant extracts, individually or in combination, as antimicrobials, antioxidants, or digestibility enhancers in animal feeds. Research results on the factors affecting their action, such as plant variety, harvest time, processing, extraction, as well as the technology employed to manufacture the commercial product and dietary inclusion levels show controversial results, warranting the need of further research and standardization for the effective use of plant extracts as performance enhancers, when added to animal feeds. This article aims at presenting plant extracts as alternatives to antibiotics, explaining their main modes of action as performance enhancers in broiler production.

  16. Enhancing visuospatial performance through video game training to increase learning in visuospatial science domains.

    Science.gov (United States)

    Sanchez, Christopher A

    2012-02-01

    Although previous research has demonstrated that performance on visuospatial assessments can be enhanced through relevant experience, an unaddressed question is whether such experience also produces a similar increase in target domains (such as science learning) where visuospatial abilities are directly relevant for performance. In the present study, participants completed either spatial or nonspatial training via interaction with video games and were then asked to read and learn about the geologic topic of plate tectonics. Results replicate the benefit of playing appropriate video games in enhancing visuospatial performance and demonstrate that this facilitation also manifests itself in learning science topics that are visuospatial in nature. This novel result suggests that visuospatial training not only can impact performance on measures of spatial functioning, but also can affect performance in content areas in which these abilities are utilized.

  17. Ecological validity of neurofeedback: modulation of slow wave EEG enhances musical performance.

    Science.gov (United States)

    Egner, Tobias; Gruzelier, John H

    2003-07-01

    Biofeedback-assisted modulation of electrocortical activity has been established to have intrinsic clinical benefits and has been shown to improve cognitive performance in healthy humans. In order to further investigate the pedagogic relevance of electroencephalograph (EEG) biofeedback (neurofeedback) for enhancing normal function, a series of investigations assessed the training's impact on an ecologically valid real-life behavioural performance measure: music performance under stressful conditions in conservatoire students. In a pilot study, single-blind expert ratings documented improvements in musical performance in a student group that received training on attention and relaxation related neurofeedback protocols, and improvements were highly correlated with learning to progressively raise theta (5-8 Hz) over alpha (8-11 Hz) band amplitudes. These findings were replicated in a second experiment where an alpha/theta training group displayed significant performance enhancement not found with other neurofeedback training protocols or in alternative interventions, including the widely applied Alexander technique.

  18. The neural signature of emotional memories in serial crimes.

    Science.gov (United States)

    Chassy, Philippe

    2017-10-01

    Neural plasticity is the process whereby semantic information and emotional responses are stored in neural networks. It is hypothesized that the neural networks built over time to encode the sexual fantasies that motivate serial killers to act should display a unique, detectable activation pattern. The pathological neural watermark hypothesis posits that such networks comprise activation of brain sites that reflect four cognitive components: autobiographical memory, sexual arousal, aggression, and control over aggression. The neural sites performing these cognitive functions have been successfully identified by previous research. The key findings are reviewed to hypothesise the typical pattern of activity that serial killers should display. Through the integration of biological findings into one framework, the neural approach proposed in this paper is in stark contrast with the many theories accounting for serial killers that offer non-medical taxonomies. The pathological neural watermark hypothesis offers a new framework to understand and detect deviant individuals. The technical and legal issues are briefly discussed. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Cognitive, emotional and social markers of serial murdering.

    Science.gov (United States)

    Angrilli, Alessandro; Sartori, Giuseppe; Donzella, Giovanna

    2013-01-01

    Although criminal psychopathy is starting to be relatively well described, our knowledge of the characteristics and scientific markers of serial murdering is still very poor. A serial killer who murdered more than five people, KT, was administered a battery of standardized tests aimed at measuring neuropsychological impairment and social/emotional cognition deficits. KT exhibited a striking dissociation between a high level of emotional detachment and a low score on the antisocial behavior scale on the Psychopathy Checklist-Revised (PCL-R). The Minnesota Multiphasic Personality Inventory-2 showed a normal pattern with the psychotic triad at borderline level. KT had a high intelligence score and showed almost no impairment in cognitive tests sensitive to frontal lobe dysfunction (Wisconsin Card Sorting Test, Theory of Mind, Tower of London, this latter evidenced a mild impairment in planning performance). In the tests on moral, emotional and social cognition, his patterns of response differed from matched controls and from past reports on criminal psychopaths as, unlike these individuals, KT exhibited normal recognition of fear and a relatively intact knowledge of moral rules but he was impaired in the recognition of anger, embarrassment and conventional social rules. The overall picture of KT suggests that serial killing may be closer to normality than psychopathy defined according to either the DSM IV or the PCL-R, and it would be characterized by a relatively spared moral cognition and selective deficits in social and emotional cognition domains.

  20. Stochastic modeling of a serial killer.

    Science.gov (United States)

    Simkin, M V; Roychowdhury, V P

    2014-08-21

    We analyze the time pattern of the activity of a serial killer, who during 12 years had murdered 53 people. The plot of the cumulative number of murders as a function of time is of "Devil's staircase" type. The distribution of the intervals between murders (step length) follows a power law with the exponent of 1.4. We propose a model according to which the serial killer commits murders when neuronal excitation in his brain exceeds certain threshold. We model this neural activity as a branching process, which in turn is approximated by a random walk. As the distribution of the random walk return times is a power law with the exponent 1.5, the distribution of the inter-murder intervals is thus explained. We illustrate analytical results by numerical simulation. Time pattern activity data from two other serial killers further substantiate our analysis. Copyright © 2014 Elsevier Ltd. All rights reserved.

  1. Performance Evaluation Criterion at Equal Pumping Power for Enhanced Performance Heat Transfer Surfaces

    Directory of Open Access Journals (Sweden)

    Rajendra Karwa

    2013-01-01

    Full Text Available The existing equations for the thermal performance evaluation, at equal pumping power for the artificially roughened and smooth surfaced multitube and rectangular duct heat exchangers, have been critically reviewed because the literature survey indicates that a large number of researchers have not interpreted these equations correctly. Three of the most widely used equations have been restated with clearly defined constraints and conditions for their application. Two new equations have been developed for the design constraints not covered earlier.

  2. The Importance of the Study of Cognitive Performance Enhancement for U.S. National Security.

    Science.gov (United States)

    Malish, Richard G

    2017-08-01

    The American military is embarking on the 'Third Offset'-a strategy designed to produce seismic shifts in the future of warfare. Central to the approach is the conjoining of humans, technology, and machines to deliver a decisive advantage on the battlefield. Because technology will spread rapidly and globally, tactical overmatch will occur when American operators possess a competitive edge in cognition. Investigation of cognitive enhancing therapeutics is not widely articulated as an adjunct to the Third Offset, yet failure to study promising agents could represent a strategic vulnerability. Because of its legacy of research into therapeutic agents to enhance human-machine interplay, the aerospace medical community represents a front-running candidate to perform this work. Notably, there are strong signals emanating from gambling, academic, and video-gaming enterprises that already-developed stimulants and other agents provide cognitive benefits. These agents should be studied not only for reasons of national security, but also because cognitive enhancement may be a necessary step in the evolution of humankind. To illustrate these points, this article will assert that: 1) the need to preserve and enhance physical and cognitive health will become more and more important over the next century; 2) aeromedical specialists are in a position to take the lead in the endeavor to enhance cognition; 3) signals of enhancement of the type useful to both military and medical efforts exist aplenty in today's society; and 4) the aeromedical community should approach human enhancement research deliberately but carefully.Malish RG. The importance of the study of cognitive performance enhancement for U.S. national security. Aerosp Med Hum Perform. 2017; 88(8):773-778.

  3. Vibration-induced coherence enhancement of the performance of a biological quantum heat engine.

    Science.gov (United States)

    Chen, Hong-Bin; Chiu, Pin-Yi; Chen, Yueh-Nan

    2016-11-01

    Photosynthesis has been a long-standing research interest due to its fundamental importance. Recently, studies on photosynthesis processes also have inspired attention from a thermodynamical aspect when considering photosynthetic apparatuses as biological quantum heat engines. Quantum coherence is shown to play a crucial role in enhancing the performance of these quantum heat engines. Based on the experimentally reported structure, we propose a quantum heat engine model with a non-Markovian vibrational mode. We show that one can obtain a performance enhancement easily for a wide range of parameters in the presence of the vibrational mode. Our results provide insights into the photosynthetic processes and a design principle mimicking natural organisms.

  4. Electrodeposition of Adherent Polypyrrole Film on Titanium Surface with Enhanced Anti-corrosion Performance

    Directory of Open Access Journals (Sweden)

    Tan Jilin

    2017-01-01

    Full Text Available A method of producing extremely adhesive polypyrrole film on Titanium (Ti substrate was investigated. The Ti substrate was chemically pretreated and then modified by polydopamine (PDA, the polypyrrole film synthesized by electrochemical method on the treated Ti substrate displayed good adhesion and enhanced anticorrosion performance. The study of the corrosion process was conducted through open circuit potential, tafel polarization and alternating current impedance test. The adhesive polypyrrole film coated titanium showed higher positive shift in corrosion potential and lower corrosion rate, indicating the great enhanced anti-corrosion performance.

  5. Vibration-induced coherence enhances the performance of a biological quantum heat engine

    CERN Document Server

    Chen, Hong-Bin; Chen, Yueh-Nan

    2016-01-01

    Photosynthesis has been the long-standing research interest due to its fundamental importance. Recently, studies on photosynthesis processes also inspire attention from thermodynamical aspect when considering photosynthetic apparatuses as biological quantum heat engines. Quantum coherence is shown to play a crucial role in enhancing the performance of these quantum heat engines. Based on the experimentally reported structure, we propose a quantum heat engine model with a non-Markovian vibrational mode. We show that one can obtain a performance enhancement easily for a wide range of parameters in the presence of the vibrational mode. Our results suggest new insights into the photosynthetic processes and a design principle mimicking natural organisms.

  6. Stochastic modeling of a serial killer

    OpenAIRE

    Simkin, M. V.; Roychowdhury, V. P.

    2014-01-01

    We analyze the time pattern of the activity of a serial killer, who during twelve years had murdered 53 people. The plot of the cumulative number of murders as a function of time is of "Devil's staircase" type. The distribution of the intervals between murders (step length) follows a power law with the exponent of 1.4. We propose a model according to which the serial killer commits murders when neuronal excitation in his brain exceeds certain threshold. We model this neural activity as a bran...

  7. Attitudes and Motivations of Competitive Cyclists Regarding Use of Banned and Legal Performance Enhancers

    Directory of Open Access Journals (Sweden)

    Nkaku R. Kisaalita

    2014-03-01

    Full Text Available Drug ‘doping’ and the use of banned performance enhancing products (PEPs remains an issue in virtually all competitive sports despite penal consequences and known health risks. The lines distinguishing “fair” and “unfair” performance enhancement have become increasingly blurred. Few studies have explored how attitudes towards legal performance enhancers (drugs/substances, diet, and equipment modifications may influence motivations to use banned PEPs. In the present study, 68 competitive cyclists completed a survey examining the importance of choosing banned and non-banned PEPs using World Anti-Doping Agency (WADA and Union Cycliste Internationale (UCI criteria. Results showed that over 60 percent of cyclists used non-banned PEPs while 8 percent used banned PEPs. Health was overall the most important factor in choosing a PEP while apprehension by a doping agency was least important. Mixed- model ANOVA analyses revealed that motivations to use banned PEPs were complex, as the importance of health, violating the sprit of the sport, performance improvement, and getting caught were differentially influenced by PEP legality (p 0.05. Our findings illustrate the multifactorial nature of PEP use/doping attitudes and highlight the unique role that “legal” performance enhancement may plays in influencing banned and/or unethical sports behaviors.

  8. Enhancement of the antimicrobial performance of biocidal formulations used for the preservation of white mineral dispersions.

    Science.gov (United States)

    Di Maiuta, Nicola; Schwarzentruber, Patrick; Dow, Crawford S

    2011-01-01

    Biocides play an important role in the preservation of white mineral dispersions (WMD). Due to the occurrence of biocide-resistant bacteria and technical limitations in the use of biocides, new preservation strategies are required-like the enhancement of biocides by non-biocidal compounds. The aim of this study was to evaluate the biocide enhancement performance of lithium against various biocide-resistant bacteria in WMD. Subsequently, the minimal enhancing concentration (MEC) of lithium and the bioavailability of lithium in respect to the mode of introduction into WMD were investigated. The antimicrobial performance of biocidal formulations comprising isothiazolinones and formaldehyde releasers or isothiazolinones and glutaraldehyde has been evaluated against the related resistant bacterial spectrum in the presence of lithium. The MEC of lithium ranged from 1,350 to 1,500 ppm (based on the liquid phase weight of a WMD with 75% solids) for formaldehyde releasers and glutaraldehyde-based biocidal formulations, respectively. The biocide enhancing property of lithium was independent of whether lithium was introduced into WMD via a lithium-neutralised dispersant, added during the calcium carbonate grinding step, or dosed into the final product. Lithium is a non-biocidal compound which has been discovered to be a potent and universal biocide enhancer. Lithium boosts the biocidal activity of various biocides and provides a novel technique to overcome biocide resistance in WMD. Such a biocide enhancer represents a breakthrough that offers a potential tool to revolutionise the consumption of biocidal agents in the WMD producing industry.

  9. Serial-omics characterization of equine urine.

    Directory of Open Access Journals (Sweden)

    Min Yuan

    Full Text Available Horse urine is easily collected and contains molecules readily measurable using mass spectrometry that can be used as biomarkers representative of health, disease or drug tampering. This study aimed at analyzing microliter levels of horse urine to purify, identify and quantify proteins, polar metabolites and non-polar lipids. Urine from a healthy 12 year old quarter horse mare on a diet of grass hay and vitamin/mineral supplements with limited pasture access was collected for serial-omics characterization. The urine was treated with methyl tert-butyl ether (MTBE and methanol to partition into three distinct layers for protein, non-polar lipid and polar metabolite content from a single liquid-liquid extraction and was repeated two times. Each layer was analyzed by high performance liquid chromatography-high resolution tandem mass spectrometry (LC-MS/MS to obtain protein sequence and relative protein levels as well as identify and quantify small polar metabolites and lipids. The results show 46 urine proteins, many related to normal kidney function, structural and circulatory proteins as well as 474 small polar metabolites but only 10 lipid molecules. Metabolites were mostly related to urea cycle and ammonia recycling as well as amino acid related pathways, plant diet specific molecules, etc. The few lipids represented triglycerides and phospholipids. These data show a complete mass spectrometry based-omics characterization of equine urine from a single 333 μL mid-stream urine aliquot. These omics data help serve as a baseline for healthy mare urine composition and the analyses can be used to monitor disease progression, health status, monitor drug use, etc.

  10. Performance enhancement study of mobile air conditioning system using microchannel heat exchangers

    Energy Technology Data Exchange (ETDEWEB)

    Qi, Zhaogang; Zhao, Yu.; Chen, Jiangping [Institute of Refrigeration and Cryogenics, Shanghai Jiao Tong University, No. 800, Dongchuan Road, Shanghai 200240 (China)

    2010-03-15

    In the present paper, two retrofitted compact and high efficient microchannel heat exchangers were proposed. The new microchannel heat exchangers have advantages in compactness (17.2% and 15.1% volume reduction for evaporator and condenser, respectively), weight (2.8% and 14.9% lighter for evaporator and condenser, respectively), heat transfer characteristics compared with the currently used heat exchangers in mobile air conditioning (MAC) industry. One enhanced and one baseline R134a MAC systems were established including the new microchannel heat exchangers and the traditional MAC heat exchangers, respectively. The system performances have been experimentally carried out under variable ambient conditions in psychrometric calorimeter test bench. The optimal system refrigerant charge amounts for both systems were tested and the results showed that the enhanced system with more compact heat exchangers could reduce system charge amount and the minimum effective charge amount was less than that of the baseline system. The enhanced system could supply more cooling capacity to car compartment under all test conditions because of higher performance heat exchangers. The coefficient of performance (COP) of the enhanced system was slightly lower than that of the baseline system under idle conditions but higher under all the other test conditions. Cooling capacity and COP of the enhanced system was increased by about 5% and 8% under high vehicle speed condition. (author)

  11. Does External Knowledge Sourcing Enhance Market Performance? Evidence from the Korean Manufacturing Industry.

    Science.gov (United States)

    Lee, Kibaek; Yoo, Jaeheung; Choi, Munkee; Zo, Hangjung; Ciganek, Andrew P

    2016-01-01

    Firms continuously search for external knowledge that can contribute to product innovation, which may ultimately increase market performance. The relationship between external knowledge sourcing and market performance is not well-documented. The extant literature primarily examines the causal relationship between external knowledge sources and product innovation performance or to identify factors which moderates the relationship between external knowledge sourcing and product innovation. Non-technological innovations, such as organization and marketing innovations, intervene in the process of external knowledge sourcing to product innovation to market performance but has not been extensively examined. This study addresses two research questions: does external knowledge sourcing lead to market performance and how does external knowledge sourcing interact with a firm's different innovation activities to enhance market performance. This study proposes a comprehensive model to capture the causal mechanism from external knowledge sourcing to market performance. The research model was tested using survey data from manufacturing firms in South Korea and the results demonstrate a strong statistical relationship in the path of external knowledge sourcing (EKS) to product innovation performance (PIP) to market performance (MP). Organizational innovation is an antecedent to EKS while marketing innovation is a consequence of EKS, which significantly influences PIP and MP. The results imply that any potential EKS effort should also consider organizational innovations which may ultimately enhance market performance. Theoretical and practical implications are discussed as well as concluding remarks.

  12. ANALYSIS OF CROSS LAYER SCHEMES TO ENHANCE TCP PERFORMANCE IN MANET

    Directory of Open Access Journals (Sweden)

    I. Sumaiya Thaseen

    2012-09-01

    Full Text Available Wireless communication is a major component of mobile computing. Transmission Control Protocol suffers from performance degradation in wireless environments. Due to high mobility and varying bit error rate in these environments, any packet loss that occurs is misinterpreted by the TCP as congestion and invokes congestion control mechanisms thereby degrading performance. Hence the performance of wireless networks is improved by introducing a cross layer design to exchange information between different layers. Cross layer optimizations produced many promising results which initiated research activity in this domain. This paper mainly focuses on cross layer proposals between network and transport layer and various TCP schemes employed to enhance performance.

  13. The eyeball killer: serial killings with postmortem globe enucleation.

    Science.gov (United States)

    Coyle, Julie; Ross, Karen F; Barnard, Jeffrey J; Peacock, Elizabeth; Linch, Charles A; Prahlow, Joseph A

    2015-05-01

    Although serial killings are relatively rare, they can be the cause of a great deal of anxiety while the killer remains at-large. Despite the fact that the motivations for serial killings are typically quite complex, the psychological analysis of a serial killer can provide valuable insight into how and why certain individuals become serial killers. Such knowledge may be instrumental in preventing future serial killings or in solving ongoing cases. In certain serial killings, the various incidents have a variety of similar features. Identification of similarities between separate homicidal incidents is necessary to recognize that a serial killer may be actively killing. In this report, the authors present a group of serial killings involving three prostitutes who were shot to death over a 3-month period. Scene and autopsy findings, including the unusual finding of postmortem enucleation of the eyes, led investigators to recognize the serial nature of the homicides. © 2015 American Academy of Forensic Sciences.

  14. Design and Demonstration of Emergency Control Modes for Enhanced Engine Performance

    Science.gov (United States)

    Liu, Yuan; Litt, Jonathan S.; Guo, Ten-Huei

    2013-01-01

    A design concept is presented for developing control modes that enhance aircraft engine performance during emergency flight scenarios. The benefits of increased engine performance to overall vehicle survivability during these situations may outweigh the accompanied elevated risk of engine failure. The objective involves building control logic that can consistently increase engine performance beyond designed maximum levels based on an allowable heightened probability of failure. This concept is applied to two previously developed control modes: an overthrust mode that increases maximum engine thrust output and a faster response mode that improves thrust response to dynamic throttle commands. This paper describes the redesign of these control modes and presents simulation results demonstrating both enhanced engine performance and robust maintenance of the desired elevated risk level.

  15. Enhancement of device performance of organic solar cells by an interfacial perylene derivative layer

    KAUST Repository

    Kim, Inho

    2010-05-26

    We report that device performance of organic solar cells consisting of zinc phthalocyanine and fullerene (C60) can be enhanced by insertion of a perylene derivative interfacial layer between fullerene and bathocuproine (BCP) exciton blocking layer (EBL). The morphology of the BCP is influenced by the underlying N,N′-dihexyl-perylene-3,4,9,10-bis(dicarboximide) (PTCDI-C6), which promotes migration of the cathode metal into the BCP layer. Insertion of a PTCDI-C6 layer between fullerene and BCP layers enhances the power conversion efficiency to 2.5%, an improvement of 32% over devices without PTCDI-C6 layer. The enhancement in device performance by insertion of PTCDI-C6 is attributed to a reduction in series resistance due to promoted metal migration into BCP and optimized optical interference effects in multilayered devices. © 2010 American Chemical Society.

  16. Enhancing the Responsivity of Uncooled Infrared Detectors Using Plasmonics for High-Performance Infrared Spectroscopy

    Directory of Open Access Journals (Sweden)

    Amr Shebl Ahmed

    2017-04-01

    Full Text Available A lead zirconate titanate (PZT;Pb(Zr0.52Ti0.48O3 layer embedded infrared (IR detector decorated with wavelength-selective plasmonic crystals has been investigated for high-performance non-dispersive infrared (NDIR spectroscopy. A plasmonic IR detector with an enhanced IR absorption band has been designed based on numerical simulations, fabricated by conventional microfabrication techniques, and characterized with a broadly tunable quantum cascade laser. The enhanced responsivity of the plasmonic IR detector at specific wavelength band has improved the performance of NDIR spectroscopy and pushed the limit of detection (LOD by an order of magnitude. In this paper, a 13-fold enhancement in the LOD of a methane gas sensing using NDIR spectroscopy is demonstrated with the plasmonic IR detector.

  17. The Influence of Serial Carbohydrate Mouth Rinsing on Power Output during a Cycle Sprint.

    Science.gov (United States)

    Phillips, Shaun M; Findlay, Scott; Kavaliauskas, Mykolas; Grant, Marie Clare

    2014-05-01

    The objective of the study was to investigate the influence of serial administration of a carbohydrate (CHO) mouth rinse on performance, metabolic and perceptual responses during a cycle sprint. Twelve physically active males (mean (± SD) age: 23.1 (3.0) years, height: 1.83 (0.07) m, body mass (BM): 86.3 (13.5) kg) completed the following mouth rinse trials in a randomized, counterbalanced, double-blind fashion; 1. 8 x 5 second rinses with a 25 ml CHO (6% w/v maltodextrin) solution, 2. 8 x 5 second rinses with a 25 ml placebo (PLA) solution. Following mouth rinse administration, participants completed a 30 second sprint on a cycle ergometer against a 0.075 g·kg(-1) BM resistance. Eight participants achieved a greater peak power output (PPO) in the CHO trial, resulting in a significantly greater PPO compared with PLA (13.51 ± 2.19 vs. 13.20 ± 2.14 W·kg(-1), p 0.05). No significant between-trials difference was reported for fatigue index, perceived exertion, arousal and nausea levels, or blood lactate and glucose concentrations. Serial administration of a CHO mouth rinse may significantly improve PPO during a cycle sprint. This improvement appears confined to the first 5 seconds of the sprint, and may come at a greater relative cost for the remainder of the sprint. Key pointsThe paper demonstrates that repeated administration of a carbohydrate mouth rinse can significantly improve peak power output during a single 30 second cycle sprint.The ergogenic effect of the carbohydrate mouth rinse may relate to the duration of exposure of the oral cavity to the mouth rinse, and associated greater stimulation of oral carbohydrate receptors.The significant increase in peak power output with the carbohydrate mouth rinse may come at a relative cost for the remainder of the sprint, evidenced by non-significantly lower mean power output and a greater fatigue index in the carbohydrate vs. placebo trial.Serial administration of a carbohydrate mouth rinse may be beneficial for

  18. Enhanced

    Directory of Open Access Journals (Sweden)

    Martin I. Bayala

    2014-06-01

    Full Text Available Land Surface Temperature (LST is a key parameter in the energy balance model. However, the spatial resolution of the retrieved LST from sensors with high temporal resolution is not accurate enough to be used in local-scale studies. To explore the LST–Normalised Difference Vegetation Index relationship potential and obtain thermal images with high spatial resolution, six enhanced image sharpening techniques were assessed: the disaggregation procedure for radiometric surface temperatures (TsHARP, the Dry Edge Quadratic Function, the Difference of Edges (Ts∗DL and three models supported by the relationship of surface temperature and water stress of vegetation (Normalised Difference Water Index, Normalised Difference Infrared Index and Soil wetness index. Energy Balance Station data and in situ measurements were used to validate the enhanced LST images over a mixed agricultural landscape in the sub-humid Pampean Region of Argentina (PRA, during 2006–2010. Landsat Thematic Mapper (TM and Moderate Resolution Imaging Spectroradiometer (EOS-MODIS thermal datasets were assessed for different spatial resolutions (e.g., 960, 720 and 240 m and the performances were compared with global and local TsHARP procedures. Results suggest that the Ts∗DL technique is the most adequate for simulating LST to high spatial resolution over the heterogeneous landscape of a sub-humid region, showing an average root mean square error of less than 1 K.

  19. Technology-Enhanced Learning in Sports Education Using Clickers: Satisfaction, Performance and Immediacy

    Science.gov (United States)

    Constantinou, Vaso; Ioannou, Andri

    2016-01-01

    The article addresses ICT in Education by describing an empirical investigation of technology-enhanced sports education. The study examines the use of clickers by 162 Judo athletes during seminars on the rules and regulations of the sport. Results are based on quantitative data collected on athletes' performances and attitudes and qualitative data…

  20. Using Interdependent Group-Oriented Reinforcement to Enhance Academic Performance in General Education Classrooms

    Science.gov (United States)

    Skinner, Christopher H.; Williams, Robert L.; Neddenriep, Christine E.

    2004-01-01

    In their meta-analysis, Stage and Quiroz (1997) found that group-oriented contingencies yielded the largest effect size of interventions designed to reduce inappropriate behaviors in public schools. However, such procedures may be underutilized for enhancing academic performance and learning. The current article describes how interdependent…

  1. Prevalence of use of performance enhancing drugs by fitness centre members

    NARCIS (Netherlands)

    Stubbe, J.H.; Chorus, A.M.J.; Frank, L.E.; de Hon, O.; van der Heijden, P.G.M.

    2014-01-01

    Studies on the use of performance enhancing drugs (PED) in fitness centres rely predominately on conventional survey methods using direct questioning. However, research indicates that direct questioning of sensitive information is characterized by under-reporting. The aim of the present study was to

  2. Metal-Ion-Modified Black Phosphorus with Enhanced Stability and Transistor Performance.

    Science.gov (United States)

    Guo, Zhinan; Chen, Si; Wang, Zhongzheng; Yang, Zhenyu; Liu, Fei; Xu, Yanhua; Wang, Jiahong; Yi, Ya; Zhang, Han; Liao, Lei; Chu, Paul K; Yu, Xue-Feng

    2017-11-01

    Black phosphorus (BP), a burgeoning elemental 2D semiconductor, has aroused increasing scientific and technological interest, especially as a channel material in field-effect transistors (FETs). However, the intrinsic instability of BP causes practical concern and the transistor performance must also be improved. Here, the use of metal-ion modification to enhance both the stability and transistor performance of BP sheets is described. Ag + spontaneously adsorbed on the BP surface via cation-π interactions passivates the lone-pair electrons of P thereby rendering BP more stable in air. Consequently, the Ag + -modified BP FET shows greatly enhanced hole mobility from 796 to 1666 cm 2 V -1 s -1 and ON/OFF ratio from 5.9 × 10 4 to 2.6 × 10 6 . The mechanisms pertaining to the enhanced stability and transistor performance are discussed and the strategy can be extended to other metal ions such as Fe 3+ , Mg 2+ , and Hg 2+ . Such stable and high-performance BP transistors are crucial to electronic and optoelectronic devices. The stability and semiconducting properties of BP sheets can be enhanced tremendously by this novel strategy. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. A Performance Enhanced Interactive Learning Workshop Model as a Supplement for Organic Chemistry Instruction

    Science.gov (United States)

    Phillips, Karen E. S.; Grose-Fifer, Jilliam

    2011-01-01

    In this study, the authors describe a Performance Enhanced Interactive Learning (PEIL) workshop model as a supplement for organic chemistry instruction. This workshop model differs from many others in that it includes public presentations by students and other whole-class-discussion components that have not been thoroughly investigated in the…

  4. Modified processing techniques of a DNA biopolymer for enhanced performance in photonics applications

    Science.gov (United States)

    Ouchen, Fahima; Sotzing, Gregory A.; Miller, Trisha L.; Singh, Kristi M.; Telek, Brian A.; Lesko, Alyssa C.; Aga, Roberto; Fehrman-Cory, Emily M.; Yaney, Perry P.; Grote, James G.; Bartsch, Carrie M.; Heckman, Emily M.

    2012-10-01

    Significant modifications have been made in the processing techniques developed to transform purified, marine-based deoxyribonucleic acid (DNA) into a biopolymer suitable for optical and electronic device fabrication. This technique employs a modified soxhlet-dialysis rinsing process to completely remove excess ionic contaminants from the DNA biopolymer, resulting in a material with greater mechanical stability and enhanced performance reproducibility.

  5. Peace Management and Enhanced Academic Performance of Tertiary Institutions in South-South Nigeria

    Science.gov (United States)

    Ebuara, Victor Obule; Ekpoh, Uduak Imo

    2011-01-01

    This study was embarked upon with a view to examining the need for peace in the management of tertiary institutions towards enhancing academic performance in south-south Nigeria. Three hypotheses and one research question guided the study. One thousand, two hundred and nineteen (1219) academic and non-academic staff were selected for the study. A…

  6. Caffeine Consumption, Expectancies of Caffeine-Enhanced Performance, and Caffeinism Symptoms among University Students.

    Science.gov (United States)

    Bradley, John R.; Petree, Allen

    1990-01-01

    Gathered self-report data on college students' (n=797) expectations of caffeine-enhanced performance, level of beverage caffeine consumed daily, and caffeinism signs experienced after consumption of caffeinated beverages. Results supported extending the expectancies model of substance use motivation from alcohol to caffeine. (Author/ABL)

  7. Stable silver/biopolymer hybrid plasmonic nanostructures for high performance surface enhanced raman scattering (SERS)

    Science.gov (United States)

    Silver/biopolymer nanoparticles were prepared by adding 100 mg silver nitrate to 2% polyvinyl alcohol solution and reduced the silver nitrate into silver ion using 2 % trisodium citrate for high performance Surface Enhanced Raman Scattering (SERS) substrates. Optical properties of nanoparticle were ...

  8. A composite generator film impregnated with cellulose nanocrystals for enhanced triboelectric performance

    Science.gov (United States)

    Jun Peng; Huilong Zhang; Qifeng Zheng; Craig M. Clemons; Ronald C. Sabo; Shaoqin Gong; Zhenqiang Ma; Lih-Sheng Turng

    2017-01-01

    A novel polydimethylsiloxane (PDMS)/cellulose nanocrystal flake (CNCF) composite triboelectric nanogenerator (CTG) using CNCFs as effective dielectrics a 10-times-enhanced triboelectric performance compared with its pure PDMS counterpart. Positive charges generated on the surface of the CNCFs during cyclic compression boosted electron transfer and induced extra charges...

  9. Doping Attitudes and the Use of Legal and Illegal Performance-Enhancing Substances among Italian Adolescents

    Science.gov (United States)

    Mallia, Luca; Lucidi, Fabio; Zelli, Arnaldo; Violani, Cristiano

    2013-01-01

    Using retrospective self-reporting, rates of illegal and legal performance-enhancing substance (PES) use in the past three months among more than 3,400 Italian high school adolescents were obtained and estimated. The study focused on the extent to which these sociodemographic characteristics and illegal PES use were associated with adolescents'…

  10. Social psychological determinants of the use of performance-enhancing drugs by gym users

    NARCIS (Netherlands)

    Wiefferink, C.H.; Detmar, S.B.; Coumans, B.; Vogels, T.; Paulussen, T.G.W.

    2008-01-01

    The aim of this study is to identify the social psychological determinants of the use of performance-enhancing drugs by gym users who practice bodybuilding, fitness, powerlifting or combat sports. In this questionnaire-based study, 144 respondents answered questions on their actual use and intention

  11. The ultrasound-enhanced bioscouring performance of four polygalacturonase enzymes obtained from rhizopus oryzae

    Science.gov (United States)

    An analytical and statistical method has been developed to measure the ultrasound-enhanced bioscouring performance of milligram quantities of endo- and exo-polygalacturonase enzymes obtained from Rhizopus oryzae fungi. UV-Vis spectrophotometric data and a general linear mixed models procedure indic...

  12. Drug Testing US Student-Athletes for Performance-Enhancing Substance Misuse: A Flawed Process.

    Science.gov (United States)

    Bahrke, Michael S

    2015-01-01

    The author argues that drug testing of U.S. high school students for performance-enhancing substance misuse is invasive, expensive, and the low number of positive test results do not justify the costs, especially in financially strapped school districts where this money would be better spent on injury prevention for athletes and the education of all students.

  13. Supplemental Instruction in Introductory Biology I: Enhancing the Performance and Retention of Underrepresented Minority Students

    Science.gov (United States)

    Rath, Kenneth A.; Peterfreund, Alan R.; Xenos, Samuel P.; Bayliss, Frank; Carnal, Nancy

    2007-01-01

    Supplemental instruction classes have been shown in many studies to enhance performance in the supported courses and even to improve graduation rates. Generally, there has been little evidence of a differential impact on students from different ethnic/racial backgrounds. At San Francisco State University, however, supplemental instruction in the…

  14. Teaching Social Skills to Enhance Work Performance in a Child Care Setting

    Science.gov (United States)

    Gear, Sabra; Bobzien, Jonna; Judge, Sharon; Raver, Sharon A.

    2011-01-01

    Adults with intellectual disabilities face difficulty seeking employment in the community workforce. Using a single-subject design, this study examined the utility of role playing and self-management strategies to enhance work performance by promoting the social skills of a young woman with Down syndrome working in a community child care setting.…

  15. Cortical laminar necrosis in brain infarcts: serial MRI

    Energy Technology Data Exchange (ETDEWEB)

    Siskas, N.; Lefkopoulos, A.; Ioannidis, I.; Charitandi, A.; Dimitriadis, A.S. [Radiology Department, AHEPA University Hospital, Aristotele University of Thessaloniki (Greece)

    2003-05-01

    High-signal cortical lesions are observed on T1-weighted images in cases of brain infarct. Histological examination has demonstrated these to be ''cortical laminar necrosis'', without haemorrhage or calcification. We report serial MRI in this condition in 12 patients with brain infarcts. We looked at high-signal lesions on T1-weighted images, chronological changes in signal intensity and contrast enhancement. High-signal cortical lesions began to appear about 2 weeks after the ictus, were prominent at 1 - 2 months, then became less evident, but occasionally remained for up to 1.5 years. They gave high signal or were isointense on T2-weighted images and did not give low signal at any stage. Contrast enhancement of these lesions was prominent at 1 - 2 months, and less apparent from 3 months, but was seen up to 5 months. (orig.)

  16. [Serial angiofluorography in the operation theater].

    Science.gov (United States)

    Maurer, H J

    1981-03-01

    Using a 33 cm or 36 cm image amplifier in conjunction with a 100 mm camera, fluoroangiography can be employed as a routine method in theatre too. Serial photography can also be taken in conjunction with an electronic programmes selector while saving film and keeping the dosage as low as possible.

  17. A Serials Holdings List Using UNIX Refer.

    Science.gov (United States)

    Boyce, Judith I.; Boyce, Bert R.

    1987-01-01

    Describes the production of an automated union list of serials holdings at minimal cost by a small consortium of state government libraries in Louisiana. Use of the UNIX Refer system without any modifications for data entry and production is described. (EM)

  18. Advances in Serials Management. Volume 6.

    Science.gov (United States)

    Hepfer, Cindy, Ed.; Gammon, Julia, Ed.; Malinowski, Teresa, Ed.

    In order to further discussion and support constructive change, this volume presents the following eight papers on various dimensions of serials management: (1) "CD-ROMs, Surveys, and Sales: The OSA [Optical Society of America] Experience" (Frank E. Harris and Alan Tourtlotte); (2) "Management and Integration of Electronic Journals into the…

  19. Serial analysis of gene expression (SAGE)

    NARCIS (Netherlands)

    van Ruissen, Fred; Baas, Frank

    2007-01-01

    In 1995, serial analysis of gene expression (SAGE) was developed as a versatile tool for gene expression studies. SAGE technology does not require pre-existing knowledge of the genome that is being examined and therefore SAGE can be applied to many different model systems. In this chapter, the SAGE

  20. Membrane installation for enhanced up-flow anaerobic sludge blanket (UASB) performance.

    Science.gov (United States)

    Liu, Yin; Zhang, Kaisong; Bakke, Rune; Li, Chunming; Liu, Haining

    2013-09-01

    It is postulated that up-flow anaerobic sludge blanket (UASB) reactor efficiency can be enhanced by a membrane immersed in the reactor to operate it as an anaerobic membrane bioreactor (AnMBR) for low-strength wastewater treatment. This postulate was tested by comparing the performance with and without a hollow fiber microfiltration membrane module immersed in UASB reactors operated at two specific organic loading rates (SOLR). Results showed that membrane filtration enhanced process performance and stability, with over 90% total organic carbon (TOC) removal consistently achieved. More than 91% of the TOC removal was achieved by suspended biomass, while less than 6% was removed by membrane filtration and digestion in the membrane attached biofilm during stable AnMBRs operation. Although the membrane and its biofilm played an important role in initial stage of the high SOLR test, linear increased TOC removal by bulk sludge mainly accounted for the enhanced process performance, implying that membrane led to enhanced biological activity of the suspended sludge. The high retention of active fine sludge particles in suspension was the main reason for this significant improvement of performance and biological activity, which led to decreased SOLR with time to a theoretical optimal level around 2  g COD/g MLVSS·d and the establishment of a microbial community dominated by Methanothrix-like microbes. It was concluded that UASB process performance can be enhanced by transforming such to AnMBR operation when the loading rate is too high for sufficient sludge retention, and/or when the effluent water quality demands are especially stringent. Copyright © 2013 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  1. Performance enhancement in the workplace: why and when healthyindividuals should disclose their reliance on pharmaceutical cognitive enhancers

    Directory of Open Access Journals (Sweden)

    Mirko D. Garasic

    2015-02-01

    Full Text Available The use of pharmaceuticals cognitive enhancers (PCE have been stirring growing interest, not only in the scientific domain but also in the popular media, and has probably had some increase recently in academic, professional and military quarters, although such increase is very difficult to assess. In line with an attitude of general acceptance towards – at least some of – the practical implementations of Human Enhancement (HE, this phenomenon is deemed as a normal procedure aimed at improving the performance of an individual as well as the overall standards of an organization. Although the vast majority of countries have some kind of restrictions to reduce the wide non-medical usage of PCE, these can be overcome quite easily. Our main objective in this theoretical paper is to underline the tension between the bio-liberal motto the use of PCE is a freely eligible personal choice, and the practical context in which its secret or concealed implementation might lead to potential dysfunctional or dangerous interpersonal or social consequences.

  2. Performance Engineering Research Center and RECOVERY. Performance Engineering Research Institution SciDAC-e Augmentation. Performance enhancement

    Energy Technology Data Exchange (ETDEWEB)

    Hollingsworth, Jeffrey K. [Univ. of Maryland, College Park, MD (United States)

    2015-10-12

    This project concentrated on various ways to improve the measurement and tuning large-scale parallel applications. This project was supplement to the project DE-FC0206ER25763 (“Performance Engineering Research Center”). The research conducted during this project is summarized in this report. The complete details of the work are available in the ten publications listed at the end of the report. It also supported the Ph.D. studies of three students and one research scientist.

  3. Assessing Working Memory in Mild Cognitive Impairment with Serial Order Recall.

    Science.gov (United States)

    Emrani, Sheina; Libon, David J; Lamar, Melissa; Price, Catherine C; Jefferson, Angela L; Gifford, Katherine A; Hohman, Timothy J; Nation, Daniel A; Delano-Wood, Lisa; Jak, Amy; Bangen, Katherine J; Bondi, Mark W; Brickman, Adam M; Manly, Jennifer; Swenson, Rodney; Au, Rhoda

    2018-01-01

    Working memory (WM) is often assessed with serial order tests such as repeating digits backward. In prior dementia research using the Backward Digit Span Test (BDT), only aggregate test performance was examined. The current research tallied primacy/recency effects, out-of-sequence transposition errors, perseverations, and omissions to assess WM deficits in patients with mild cognitive impairment (MCI). Memory clinic patients (n = 66) were classified into three groups: single domain amnestic MCI (aMCI), combined mixed domain/dysexecutive MCI (mixed/dys MCI), and non-MCI where patients did not meet criteria for MCI. Serial order/WM ability was assessed by asking participants to repeat 7 trials of five digits backwards. Serial order position accuracy, transposition errors, perseverations, and omission errors were tallied. A 3 (group)×5 (serial position) repeated measures ANOVA yielded a significant group×trial interaction. Follow-up analyses found attenuation of the recency effect for mixed/dys MCI patients. Mixed/dys MCI patients scored lower than non-MCI patients for serial position 3 (p recency; p recency effect using serial order parameters obtained from the BDT may provide a useful operational definition as well as additional diagnostic information regarding working memory deficits in MCI.

  4. Serial millisecond crystallography for routine room-temperature structure determination at synchrotrons.

    Science.gov (United States)

    Weinert, Tobias; Olieric, Natacha; Cheng, Robert; Brünle, Steffen; James, Daniel; Ozerov, Dmitry; Gashi, Dardan; Vera, Laura; Marsh, May; Jaeger, Kathrin; Dworkowski, Florian; Panepucci, Ezequiel; Basu, Shibom; Skopintsev, Petr; Doré, Andrew S; Geng, Tian; Cooke, Robert M; Liang, Mengning; Prota, Andrea E; Panneels, Valerie; Nogly, Przemyslaw; Ermler, Ulrich; Schertler, Gebhard; Hennig, Michael; Steinmetz, Michel O; Wang, Meitian; Standfuss, Jörg

    2017-09-14

    Historically, room-temperature structure determination was succeeded by cryo-crystallography to mitigate radiation damage. Here, we demonstrate that serial millisecond crystallography at a synchrotron beamline equipped with high-viscosity injector and high frame-rate detector allows typical crystallographic experiments to be performed at room-temperature. Using a crystal scanning approach, we determine the high-resolution structure of the radiation sensitive molybdenum storage protein, demonstrate soaking of the drug colchicine into tubulin and native sulfur phasing of the human G protein-coupled adenosine receptor. Serial crystallographic data for molecular replacement already converges in 1,000-10,000 diffraction patterns, which we collected in 3 to maximally 82 minutes. Compared with serial data we collected at a free-electron laser, the synchrotron data are of slightly lower resolution, however fewer diffraction patterns are needed for de novo phasing. Overall, the data we collected by room-temperature serial crystallography are of comparable quality to cryo-crystallographic data and can be routinely collected at synchrotrons.Serial crystallography was developed for protein crystal data collection with X-ray free-electron lasers. Here the authors present several examples which show that serial crystallography using high-viscosity injectors can also be routinely employed for room-temperature data collection at synchrotrons.

  5. Changes of physical performance as indicators of the response to enhanced physical education.

    Science.gov (United States)

    Shephard, R J; Lavallée, H

    1994-12-01

    The value of field performance tests in the assessment of a programme of enhanced physical education has been examined in a 3-factor study of students over all 6 primary school grades. The enhanced programme under review offered a one hour of required physical education daily from age 7 to 12 years, taught by a specialist physical educator. Control students from immediately preceding and succeeding classes continued with the standard programme, a standard single period of physical education per week taught by a nonspecialist. Subjects were classed by gender, environment (urban vs rural school) and the experimental intervention to allow analysis by MANOVA. Students in the experimental programme showed small but statistically significant gains in laboratory measures of aerobic power and muscle strength relative to controls. In general, these responses were mirrored by gains in scores on the Canadian Association for Health Physical Education and Recreation (CAHPER) field performance test battery. The latter tests also suggested gains of anaerobic power, coordination and muscular endurance. It is concluded that an enhanced programme of physical education can enhance function in primary school students, but the size of gains is not a strong argument for such programmes. Further, gains in performance test scores indicate the direction, but not necessarily the magnitude of programme responses.

  6. Carbon nanodots-based nanocomposites with enhanced photocatalytic performance and photothermal effects

    Science.gov (United States)

    Zhang, J.; Tang, Y. L.; Hu, G.; Gao, B. L.; Gan, Z. X.; Chu, P. K.

    2017-07-01

    Carbon nanomaterials with variable bandgaps exhibit wide spectral absorption, and photoluminescent nanodots have attracted much interest. In this work, carbon nanodots (CNDs) are grafted onto the surface of TiO2 nanotubes to enhance the photocatalytic properties. The CNDs increase light absorption, trap and shuttle photo-generated electrons, and enhance the pollutant adsorptivity. In addition, the synergistic photothermal effect of the CNDs-based nanocomposite facilitates photocatalysis. The CNDs-based nanocomposites with improved photothermal performance and efficient photocatalytic characteristics have large potential in environment and energy applications.

  7. Enhanced performance of polymer:fullerene bulk heterojunction solar cells upon graphene addition

    Energy Technology Data Exchange (ETDEWEB)

    Robaeys, Pieter, E-mail: pieter.robaeys@uhasselt.be; Dierckx, Wouter; Dexters, Wim; Spoltore, Donato; Drijkoningen, Jeroen [Institute for Materials Research (IMO), Hasselt University (Belgium); Bonaccorso, Francesco [Cambridge Graphene Centre, University of Cambridge, 9 JJ Thomson Avenue, Cambridge (United Kingdom); Istituto Italiano di Tecnologia, Graphene Labs, Via Morego 30, 16163 Genova (Italy); Bourgeois, Emilie; D' Haen, Jan; Haenen, Ken; Manca, Jean V.; Nesladek, Milos [Institute for Materials Research (IMO), Hasselt University (Belgium); IMOMEC, IMEC vzw (Belgium); Liesenborgs, Jori; Van Reeth, Frank [Expertise centre for Digital Media (EDM), Hasselt University (Belgium); Lombardo, Antonio; Ferrari, Andrea C. [Cambridge Graphene Centre, University of Cambridge, 9 JJ Thomson Avenue, Cambridge (United Kingdom)

    2014-08-25

    Graphene has potential for applications in solar cells. We show that the short circuit current density of P3HT (Poly(3-hexylthiophene-2,5-diyl):PCBM((6,6)-Phenyl C61 butyric acid methyl ester) solar cells is enhanced by 10% upon the addition of graphene, with a 15% increase in the photon to electric conversion efficiency. We discuss the performance enhancement by studying the crystallization of P3HT, as well as the electrical transport properties. We show that graphene improves the balance between electron and hole mobilities with respect to a standard P3HT:PCBM solar cell.

  8. A genetic dissection of breed composition and performance enhancement in the Alaskan sled dog

    Directory of Open Access Journals (Sweden)

    Runstadler Jonathan

    2010-07-01

    Full Text Available Abstract Background The Alaskan sled dog offers a rare opportunity to investigate the development of a dog breed based solely on performance, rather than appearance, thus setting the breed apart from most others. Several established breeds, many of which are recognized by the American Kennel Club (AKC, have been introduced into the sled dog population to enhance racing performance. We have used molecular methods to ascertain the constitutive breeds used to develop successful sled dog lines, and in doing so, determined the breed origins of specific performance-related behaviors. One hundred and ninety-nine Alaskan sled dogs were genotyped using 96 microsatellite markers that span the canine genome. These data were compared to that from 141 similarly genotyped purebred dog breeds. Sled dogs were evaluated for breed composition based on a variety of performance phenotypes including speed, endurance and work ethic, and the data stratified based on population structure. Results We observe that the Alaskan sled dog has a unique molecular signature and that the genetic profile is sufficient for identifying dogs bred for sprint versus distance. When evaluating contributions of existing breeds we find that the Alaskan Malamute and Siberian Husky contributions are associated with enhanced endurance; Pointer and Saluki are associated with enhanced speed and the Anatolian Shepherd demonstrates a positive influence on work ethic. Conclusion We have established a genetic breed profile for the Alaskan sled dog, identified profile variance between sprint and distance dogs, and established breeds associated with enhanced performance attributes. These data set the stage for mapping studies aimed at finding genes that are associated with athletic attributes integral to the high performing Alaskan sled dog.

  9. A genetic dissection of breed composition and performance enhancement in the Alaskan sled dog

    Science.gov (United States)

    2010-01-01

    Background The Alaskan sled dog offers a rare opportunity to investigate the development of a dog breed based solely on performance, rather than appearance, thus setting the breed apart from most others. Several established breeds, many of which are recognized by the American Kennel Club (AKC), have been introduced into the sled dog population to enhance racing performance. We have used molecular methods to ascertain the constitutive breeds used to develop successful sled dog lines, and in doing so, determined the breed origins of specific performance-related behaviors. One hundred and ninety-nine Alaskan sled dogs were genotyped using 96 microsatellite markers that span the canine genome. These data were compared to that from 141 similarly genotyped purebred dog breeds. Sled dogs were evaluated for breed composition based on a variety of performance phenotypes including speed, endurance and work ethic, and the data stratified based on population structure. Results We observe that the Alaskan sled dog has a unique molecular signature and that the genetic profile is sufficient for identifying dogs bred for sprint versus distance. When evaluating contributions of existing breeds we find that the Alaskan Malamute and Siberian Husky contributions are associated with enhanced endurance; Pointer and Saluki are associated with enhanced speed and the Anatolian Shepherd demonstrates a positive influence on work ethic. Conclusion We have established a genetic breed profile for the Alaskan sled dog, identified profile variance between sprint and distance dogs, and established breeds associated with enhanced performance attributes. These data set the stage for mapping studies aimed at finding genes that are associated with athletic attributes integral to the high performing Alaskan sled dog. PMID:20649949

  10. A genetic dissection of breed composition and performance enhancement in the Alaskan sled dog.

    Science.gov (United States)

    Huson, Heather J; Parker, Heidi G; Runstadler, Jonathan; Ostrander, Elaine A

    2010-07-22

    The Alaskan sled dog offers a rare opportunity to investigate the development of a dog breed based solely on performance, rather than appearance, thus setting the breed apart from most others. Several established breeds, many of which are recognized by the American Kennel Club (AKC), have been introduced into the sled dog population to enhance racing performance. We have used molecular methods to ascertain the constitutive breeds used to develop successful sled dog lines, and in doing so, determined the breed origins of specific performance-related behaviors.One hundred and ninety-nine Alaskan sled dogs were genotyped using 96 microsatellite markers that span the canine genome. These data were compared to that from 141 similarly genotyped purebred dog breeds. Sled dogs were evaluated for breed composition based on a variety of performance phenotypes including speed, endurance and work ethic, and the data stratified based on population structure. We observe that the Alaskan sled dog has a unique molecular signature and that the genetic profile is sufficient for identifying dogs bred for sprint versus distance. When evaluating contributions of existing breeds we find that the Alaskan Malamute and Siberian Husky contributions are associated with enhanced endurance; Pointer and Saluki are associated with enhanced speed and the Anatolian Shepherd demonstrates a positive influence on work ethic. We have established a genetic breed profile for the Alaskan sled dog, identified profile variance between sprint and distance dogs, and established breeds associated with enhanced performance attributes. These data set the stage for mapping studies aimed at finding genes that are associated with athletic attributes integral to the high performing Alaskan sled dog.

  11. Potentially fatal new trend in performance enhancement: a cautionary note on nitrite

    Directory of Open Access Journals (Sweden)

    Naughton Declan P

    2010-06-01

    Full Text Available Abstract Background Considerable interest has been shown by athletes and scientists in the potential for nitric oxide and associated vasodilators to enhance performance. This study aims to explore potential misuse of vasodilators by the athletes, and to highlight the growing concern over these agents. Methods Retrospective analyses of anonymous inquiries recorded in the Drug Information Database™ (DID™ between January 2006 and June 2008 (inclusive. In this 30-month period, the DID™ recorded 198,023 inquiries, of which 118,724 were UK Licensed Pharmaceutical products with a further 79,299 inquiries made for substance not found in the database. Results Phosphodiesterase type 5 (PDE-5 inhibitors, dominated by Viagra®, ranked 16th among the substance groups. The proportion of the inquiries made regarding PDE-5 inhibitors, especially in comparison to antibiotics, painkillers or alcohol, appears to be above the level that would normally be expected from medical need. No significant change in the months leading up to the Beijing Olympics was observed. On the contrary, the Nitric/Nitrate group showed a notable increase between 2006-2007 and 2008, suggesting a potential increase in interest in using nitric oxide among athletes. Conclusions With patents recently filed for the use of agents containing sodium nitrite/nitrate to enhance blood flow for performance enhancement in sport, coupled with anecdotal evidence from internet athlete forums and media, there is a concern that athletes may endanger their health by using vasodilators to enhance athletic performance. PDE-5 inhibitors or chemicals in the nitrate/nitrate group are currently not prohibited or tested for by the doping control agencies but some are highly dangerous to health and can lead to cardiovascular collapse, coma and death. Its promotion among athletes as a performance enhancing supplement is ethically and medically questionable.

  12. SERIAL SECTIONS THROUGH A CONTINUOUS FIBER-REINFORCED POLYMER COMPOSITE

    Directory of Open Access Journals (Sweden)

    Laurent Bizet

    2011-05-01

    Full Text Available The microstructure of a unidirectional glass-fiber composite material is described seeking especially for the influence of the stitching perpendicular to the reinforcement. Serial cuts are performed through the composite and the microstructure is quantified using global parameters and linear morphological analysis. A key result is that the stitching induces variations in fibers spacing within the yarns and in the matrix volume between the yarns. This can affect noticeably the flow of the resin during the manufacturing process and also the mechanical properties of the composite.

  13. The essential guide to Serial ATA and SATA express

    CERN Document Server

    Deming, David A

    2014-01-01

    Used in laptop and desktop computers, low-end servers, and mobile devices, Serial ATA (Advance Technology Attachment), or SATA, is the pervasive disk storage technology in use today. SATA has also penetrated the enterprise computing environment by adding hardware components for fail-over, extending command processing capabilities, and increasing device performance and link speeds. If you work in a data center or manage your company's storage resources, you will likely encounter storage solutions that require SATA software or hardware.In this book, leading storage networking technologist David

  14. Carbohydrate Mouth Rinsing Enhances High Intensity Time Trial Performance Following Prolonged Cycling

    Directory of Open Access Journals (Sweden)

    Nicholas D. Luden

    2016-09-01

    Full Text Available There is good evidence that mouth rinsing with carbohydrate (CHO solutions can enhance endurance performance (≥30 min. The impact of a CHO mouth rinse on sprint performance has been less consistent, suggesting that CHO may confer benefits in conditions of ‘metabolic strain’. To test this hypothesis, the current study examined the impact of late-exercise mouth rinsing on sprint performance. Secondly, we investigated the effects of a protein mouth rinse (PRO on performance. Eight trained male cyclists participated in three trials consisting of 120 min of constant-load cycling (55% Wmax followed by a 30 km computer-simulated time trial, during which only water was provided. Following 15 min of muscle function assessment, 10 min of constant-load cycling (3 min at 35% Wmax, 7 min at 55% Wmax was performed. This was immediately followed by a 2 km time trial. Subjects rinsed with 25 mL of CHO, PRO, or placebo (PLA at min 5:00 and 14:30 of the 15 min muscle function phase, and min 8:00 of the 10-min constant-load cycling. Magnitude-based inferential statistics were used to analyze the effects of the mouth rinse on 2-km time trial performance and the following physiological parameters: Maximum Voluntary Contract (MVC, Rating of Perceived Exertion (RPE, Heart Rate (HR, and blood glucose levels. The primary finding was that CHO ‘likely’ enhanced performance vs. PLA (3.8%, whereas differences between PRO and PLA were unclear (0.4%. These data demonstrate that late-race performance is enhanced by a CHO rinse, but not PRO, under challenging metabolic conditions. More data should be acquired before this strategy is recommended for the later stages of cycling competition under more practical conditions, such as when carbohydrates are supplemented throughout the preceding minutes/hours of exercise.

  15. Serial position markers in space: visuospatial priming of serial order working memory retrieval.

    Directory of Open Access Journals (Sweden)

    Maya De Belder

    Full Text Available Most general theories on serial order working memory (WM assume the existence of position markers that are bound to the to-be-remembered items to keep track of the serial order. So far, the exact cognitive/neural characteristics of these markers have remained largely underspecified, while direct empirical evidence for their existence is mostly lacking. In the current study we demonstrate that retrieval from verbal serial order WM can be facilitated or hindered by spatial cuing: begin elements of a verbal WM sequence are retrieved faster after cuing the left side of space, while end elements are retrieved faster after cuing the right side of space. In direct complement to our previous work--where we showed the reversed impact of WM retrieval on spatial processing--we argue that the current findings provide us with a crucial piece of evidence suggesting a direct and functional involvement of space in verbal serial order WM. We outline the idea that serial order in verbal WM is coded within a spatial coordinate system with spatial attention being involved when searching through WM, and we discuss how this account can explain several hallmark observations related to serial order WM.

  16. Design Enhancement and Performance Examination of External Rotor Switched Flux Permanent Magnet Machine for Downhole Application

    Science.gov (United States)

    Kumar, R.; Sulaiman, E.; Soomro, H. A.; Jusoh, L. I.; Bahrim, F. S.; Omar, M. F.

    2017-08-01

    The recent change in innovation and employments of high-temperature magnets, permanent magnet flux switching machine (PMFSM) has turned out to be one of the suitable contenders for seaward boring, however, less intended for downhole because of high atmospheric temperature. Subsequently, this extensive review manages the design enhancement and performance examination of external rotor PMFSM for the downhole application. Preparatory, the essential design parameters required for machine configuration are computed numerically. At that point, the design enhancement strategy is actualized through deterministic technique. At last, preliminary and refined execution of the machine is contrasted and as a consequence, the yield torque is raised from 16.39Nm to 33.57Nm while depreciating the cogging torque and PM weight up to 1.77Nm and 0.79kg, individually. In this manner, it is inferred that purposed enhanced design of 12slot-22pole with external rotor is convenient for the downhole application.

  17. A study of serial ranks via random graphs

    OpenAIRE

    Haeusler, Erich; Mason, David M.; Turova, Tatyana S.

    2000-01-01

    Serial ranks have long been used as the basis for nonparametric tests of independence in time series analysis. We shall study the underlying graph structure of serial ranks. This will lead us to a basic martingale which will allow us to construct a weighted approximation to a serial rank process. To show the applicability of this approximation, we will use it to prove two very general central limit theorems for Wald-Wolfowitz-type serial rank statistics.

  18. Administration of dehydroepiandrosterone (DHEA) enhances visual-spatial performance in postmenopausal women.

    Science.gov (United States)

    Stangl, Bethany; Hirshman, Elliot; Verbalis, Joseph

    2011-10-01

    The current article examines the effect of administering dehydroepiandrosterone (DHEA) on visual-spatial performance in postmenopausal women (N = 24, ages 55-80). The concurrent reduction of serum DHEA levels and visual-spatial performance in this population, coupled with the documented effects of DHEA's androgenic metabolites on visual-spatial performance, suggests that DHEA administration may enhance visual-spatial performance. The current experiment used a double-blind, placebo-controlled crossover design in which 50 mg of oral DHEA was administered daily in the drug condition to explore this hypothesis. Performance on the Mental Rotation, Subject-Ordered Pointing, Fragmented Picture Identification, Perceptual Identification, Same-Different Judgment, and Visual Search tasks and serum levels of DHEA, DHEAS, testosterone, estrone, and cortisol were measured in the DHEA and placebo conditions. In contrast to prior experiments using the current methodology that did not demonstrate effects of DHEA administration on episodic and short-term memory tasks, the current experiment demonstrated large beneficial effects of DHEA administration on Mental Rotation, Subject-Ordered Pointing, Fragmented Picture Identification, Perceptual Identification, and Same-Different Judgment. Moreover, DHEA administration enhanced serum levels of DHEA, DHEAS, testosterone, and estrone, and regression analyses demonstrated that levels of DHEA and its metabolites were positively related to cognitive performance on the visual-spatial tasks in the DHEA condition.

  19. Administration of Dehydroepiandrosterone (DHEA) Enhances Visual-Spatial Performance in Post-Menopausal Women

    Science.gov (United States)

    Stangl, Bethany; Hirshman, Elliot; Verbalis, Joseph

    2013-01-01

    The current paper examines the effect of administering Dehydroepiandrosterone (DHEA) on visual-spatial performance in post-menopausal women (N=24, ages 55-80). The concurrent reduction of serum DHEA levels and visual-spatial performance in this population, coupled with the documented effects of DHEA’s androgenic metabolites on visual-spatial performance, suggest that DHEA administration may enhance visual-spatial performance. The current experiment used a double-blind placebo-controlled crossover design in which 50 mg of oral DHEA was administered daily in the drug condition to explore this hypothesis. Performance on the Mental Rotation, Subject-Ordered Pointing, Fragmented Picture Identification, Perceptual Identification, Same-Different Judgment, and Visual Search tasks and serum levels of DHEA, DHEAS, testosterone, estrone and cortisol were measured in the DHEA and placebo conditions. In contrast to prior experiments using the current methodology that did not demonstrate effects of DHEA administration on episodic and short-term memory tasks, the current experiment demonstrated large beneficial effects of DHEA administration on Mental Rotation, Subject-Ordered Pointing, Fragmented Picture Identification, Perceptual Identification and Same-Different Judgment. Moreover, DHEA administration enhanced serum levels of DHEA, DHEAS, testosterone and estrone, and regression analyses demonstrated that levels of DHEA and its metabolites were positively related to cognitive performance on the visual-spatial tasks in the DHEA condition PMID:21942436

  20. The involvement of long-term serial-order memory in reading development: A longitudinal study.

    Science.gov (United States)

    Bogaerts, Louisa; Szmalec, Arnaud; De Maeyer, Marjolijn; Page, Mike P A; Duyck, Wouter

    2016-05-01

    Recent findings suggest that Hebb repetition learning-a paradigmatic example of long-term serial-order learning-is impaired in adults with dyslexia. The current study further investigated the link between serial-order learning and reading using a longitudinal developmental design. With this aim, verbal and visual Hebb repetition learning performance and reading skills were assessed in 96 Dutch-speaking children who we followed from first through second grade of primary school. We observed a positive association between order learning capacities and reading ability as well as weaker Hebb learning performance in early readers with poor reading skills even at the onset of reading instruction. Hebb learning further predicted individual differences in later (nonword) reading skills. Finally, Hebb learning was shown to explain a significant part of the variance in reading performance above and beyond phonological awareness. These findings highlight the role of serial-order memory in reading ability. Copyright © 2015 Elsevier Inc. All rights reserved.

  1. Enhancement of SOFC Cathode Electrochemical Performance Using Multi-Phase Interfaces

    Energy Technology Data Exchange (ETDEWEB)

    Morgan, Dane [Univ. of Wisconsin, Madison, WI (United States)

    2015-09-30

    This work explored the use of oxide heterostructures for enhancing the catalytic and degradation properties of solid oxide fuel cell (SOFC) cathode electrodes. We focused on heterostructures of Ruddlesden-Popper and perovskite phases. Building on previous work showing enhancement of the Ruddlesden-Popper (La,Sr)2CoO4 / perovskite (La,Sr)CoO3 heterostructure compared to pure (La,Sr)CoO3 we explored the application of related heterostructures of Ruddlesden-Popper phases on perovskite (La,Sr)(Co,Fe)O3. Our approaches included thin-film electrodes, physical and electrochemical characterization, elementary reaction kinetics modeling, and ab initio simulations. We demonstrated that Sr segregation to surfaces is likely playing a critical role in the performance of (La,Sr)CoO3 and (La,Sr)(Co,Fe)O3 and that modification of this Sr segregation may be the mechanism by which Ruddlesden-Popper coatings enhance performances. We determined that (La,Sr)(Co,Fe)O3 could be enhanced in thin films by about 10× by forming a heterostructure simultaneously with (La,Sr)2CoO4 and (La,Sr)CoO3. We hope that future work will develop this heterostructure for use as a bulk porous electrode.

  2. Enhanced Performance of Thin Film Composite Forward Osmosis Membrane by Chemical Post-Treatment

    Science.gov (United States)

    Liu, Zheng; Chen, Jiangrong; Cao, Zhen; Wang, Jian; Guo, Chungang

    2018-01-01

    Forward osmosis is an attractive technique in water purification and desalination fields. Enhancement of the forward osmosis membrane performance is essential to the application of this technique. In this study, an optimized chemical post-treatment approach which was used to improve RO membrane performance was employed for enhancing water flux of thin film composite forward osmosis membrane. Home-made polysulfide-based forward osmosis membrane was prepared and nitric acid, sulfuric acid, ethanol, 2-propanol were employed as post-treatment solutions. After a short-term treatment, all the membrane samples manifested water flux enhancement compared with their untreated counterparts. Over 50% increase of water flux had been obtained by ethanol solution treatment. The swelling, changes of hydrophobicity and solvency in both active layer and substrate were verified as the major causes for the enhancement of the water flux. It is noted that the treatment time and solution concentration should be controlled to get both appropriate water flux and reverse salt flux. The results obtained in this study will be useful for further FO membrane development and application.

  3. Enhanced physical endurance and improved memory performance following taurine administration in rats.

    Science.gov (United States)

    Sajid, Irfan; Ahmad, Saara; Emad, Shaista; Batool, Zehra; Khaliq, Saima; Anis, Lubna; Tabassum, Saiqa; Madiha, Syeda; Liaquat, Laraib; Sadir, Sadia; Perveen, Tahira; Haider, Saida

    2017-09-01

    Energy drinks enhance physical endurance and cognitive ability. The ingredients present in these drinks are considered as ergogenic and have memory boosting effects. In the present study effects of taurine administration for one week was monitored on physical exercise and memory performance in rats. Animals were divided into two groups namely control and test. Taurine was injected intraperitoneally to the test group at the dose of 100mg/kg. After one week of treatment rats were subjected to physical exercise and memory task. Results of this study revealed that rats injected with taurine for one week exhibited improved muscular strength as well as enhanced memory performance in Morris water maze and elevated plus maze. Biomarker of lipid peroxidation was significantly reduced in brain and plasma of test animals. Taurine administration also resulted in higher levels of corticosterone in this study. The results highlight the significance of taurine ingestion in energy demanding and challenging situations in athletes and young subjects.

  4. A general approach toward enhancement of pseudocapacitive performance of conducting polymers by redox-active electrolytes

    KAUST Repository

    Chen, Wei

    2014-12-01

    A general approach is demonstrated where the pseudocapacitive performance of different conducting polymers is enhanced in redox-active electrolytes. The concept is demonstrated using several electroactive conducting polymers, including polyaniline, polypyrrole, and poly(3,4-ethylenedioxythiophene). As compared to conventional electrolytes, the redox-active electrolytes, prepared by simply adding a redox mediator to the conventional electrolyte, can significantly improve the energy storage capacity of pseudocapacitors with different conducting polymers. The results show that the specific capacitance of conducting polymer based pseudocapacitors can be increased by a factor of two by utilization of the redox-active electrolytes. In fact, this approach gives some of the highest reported specific capacitance values for electroactive conducting polymers. Moreover, our findings present a general and effective approach for the enhancement of energy storage performance of pseudocapacitors using a variety of polymeric electrode materials. © 2014 Elsevier B.V. All rights reserved.

  5. Gas-exfoliated porous monolayer boron nitride for enhanced aerobic oxidative desulfurization performance

    Science.gov (United States)

    Wu, Yingcheng; Wu, Peiwen; Chao, Yanhong; He, Jing; Li, Hongping; Lu, Linjie; Jiang, Wei; Zhang, Beibei; Li, Huaming; Zhu, Wenshuai

    2018-01-01

    Hexagonal boron nitride has been regarded to be an efficient catalyst in aerobic oxidation fields, but limited by the less-exposed active sites. In this contribution, we proposed a simple green liquid nitrogen gas exfoliation strategy for preparation of porous monolayer nanosheets (BN-1). Owing to the reduced layer numbers, decreased lateral sizes and artificially-constructed pores, increased exposure of active sites was expected, further contributed to an enhanced aerobic oxidative desulfurization (ODS) performance up to ∼98% of sulfur removal, achieving ultra-deep desulfurization. This work not only introduced an excellent catalyst for aerobic ODS, but also provided a strategy for construction of some other highly-efficient monolayer two-dimensional materials for enhanced catalytic performance.

  6. Methyllithium-Doped Naphthyl-Containing Conjugated Microporous Polymer with Enhanced Hydrogen Storage Performance.

    Science.gov (United States)

    Xu, Dan; Sun, Lei; Li, Gang; Shang, Jin; Yang, Rui-Xia; Deng, Wei-Qiao

    2016-06-01

    Hydrogen storage is a primary challenge for using hydrogen as a fuel. With ideal hydrogen storage kinetics, the weak binding strength of hydrogen to sorbents is the key barrier to obtain decent hydrogen storage performance. Here, we reported the rational synthesis of a methyllithium-doped naphthyl-containing conjugated microporous polymer with exceptional binding strength of hydrogen to the polymer guided by theoretical simulations. Meanwhile, the experimental results showed that isosteric heat can reach up to 8.4 kJ mol(-1) and the methyllithium-doped naphthyl-containing conjugated microporous polymer exhibited an enhanced hydrogen storage performance with 150 % enhancement compared with its counterpart naphthyl-containing conjugated microporous polymer. These results indicate that this strategy provides a direction for design and synthesis of new materials that meet the US Department of Energy (DOE) hydrogen storage target. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Speak up! Enhancing risk performance with enterprise risk management, leadership style and employee voice

    DEFF Research Database (Denmark)

    Sax, Johanna; Torp, Simon

    2015-01-01

    Purpose: – The purpose of this paper is to test the effect of psychological safety and participative leadership style on risk performance as well as its interaction with enterprise risk management (ERM) processes to evaluate if a decentralisation in the form of a safe environment and participative......: – The paper finds that not only do both ERM and participative leadership style enhance risk performance but a positive interaction effect is also found. In addition, the findings suggest that a safe environment precede participative leadership style indicating this as a prerequisite for management...... to introduce participative leadership style. These findings underpin that an effective risk management system should include both a holistic, formalised ERM system and organisational initiatives that enhance a strategic responsiveness through employee involvement. Originality/value: – The current study...

  8. A culture of education: Enhancing school performance of youth living in residential group care in Ontario.

    Science.gov (United States)

    Gharabaghi, Kiaras

    2011-01-01

    This article presents a synthesis of what is known about the educational experiences of youth living in residential group care based on a literature review that highlights both the experiences of the youth themselves and the operational context of residential group care in Ontario as it pertains to educational performance. The author argues that there is little emphasis on education within the residential group care sector in Ontario that could translate into more productive educational experiences for youth. The article then provides a framework for developing a culture of education for residential group care that can be acted upon expeditiously. Enhancing the educational performance of young people living in group care will require a cultural approach that provides for daily and pervasive education supports and encouragement, and aims to enhance the lived experience of young people pursuant to their education.

  9. [Personality disorders, psychopathy and serial killers].

    Science.gov (United States)

    Morana, Hilda C P; Stone, Michael H; Abdalla-Filho, Elias

    2006-10-01

    To illustrate the basic characteristics of several specific personality disorders, focusing mainly in antisocial personality disorder. The differences between antisocial personality disorder and psychopathy are highlighted. Serial killers and its psychopathic aspects are also discussed. A bibliographic review was completed in order to outline convergences and divergences among different authors about this controversial issue, especially those concerning the possibility of treatment. While anti-social personality disorder is a medical diagnosis, the term "psychopathy" (which belongs to the sphere of forensic psychiatry) may be understood as a "legal diagnosis". It is not still possible to identify an effective treatment for serial killers. Personality disorders, especially of the antisocial type, still represent a formidable challenge to forensic psychiatry today. Questions as yet unanswered include the best and most humane place for patients with this condition and the nature of a standardised treatment recommendation.

  10. Performance enhancement of nylon/kevlar fiber composites through viscoelastically generated pre-stress

    OpenAIRE

    Fazal, A.; Fancey, K.S.

    2014-01-01

    Kevlar-29 fibers have high strength and stiffness but nylon 6,6 fibers have greater ductility. Thus by commingling these fibers prior to molding in a resin, the resulting hybrid composite may be mechanically superior to the corresponding single fiber-type composites. The contribution made by viscoelastically generated pre-stress, via the commingled nylon fibers, should add further performance enhancement. This paper reports on an initial study into the Charpy impact toughness and flexural sti...

  11. Tailoring Gut Microbiota for Enhanced Resilience and Performance Under Sleep-Deprived Conditions

    Science.gov (United States)

    2016-08-01

    Obesity, in part, is characterized by systemic inflammation, in which the brain - gut axis is likely to be involved (Tahergorabi and Khazaei, 2013...sleep essential? PLoS Biol. 6:1605-11. Cryan JF, and Dinan TG. (2012) Mind-altering microorganisms: the impact of the gut microbiota on brain and...AFRL-RH-WP-TR-2017-0001 Tailoring Gut Microbiota for Enhanced Resilience and Performance under Sleep-Deprived Conditions. Victor T. Chan

  12. Heat Pipe Performance Enhancement with Binary Mixture Fluids that Exhibit Strong Concentration Marangoni Effects

    OpenAIRE

    Armijo, Kenneth Miguel

    2011-01-01

    This research investigates the impact of Marangoni phenomena, with low mixture concentrations of alcohol and water, to enhance thermal transport capability of gravity-assisted heat pipes. The use of binary mixture working fluids in gravity-assisted heat pipes are shown to improve the critical heat flux (CHF) and operating performance, more so than with pure fluids. The CHF is responsible for dryout when the pumping rate of a liquid flow structure is not sufficient to provide enough fluid to t...

  13. Supplemental Instruction in Introductory Biology I: Enhancing the Performance and Retention of Underrepresented Minority Students

    OpenAIRE

    Rath, Kenneth A.; Peterfreund, Alan R.; Xenos, Samuel P.; Bayliss, Frank; Carnal, Nancy

    2007-01-01

    Supplemental instruction classes have been shown in many studies to enhance performance in the supported courses and even to improve graduation rates. Generally, there has been little evidence of a differential impact on students from different ethnic/racial backgrounds. At San Francisco State University, however, supplemental instruction in the Introductory Biology I class is associated with even more dramatic gains among students from underrepresented minority populations than the gains fou...

  14. Nonlocalized postactivation performance enhancement (PAPE) effects in trained athletes: a pilot study.

    Science.gov (United States)

    Cuenca-Fernández, Francisco; Smith, Ian C; Jordan, Matthew J; MacIntosh, Brian R; López-Contreras, Gracia; Arellano, Raúl; Herzog, Walter

    2017-10-01

    Fifteen trained athletes were assessed for postactivation performance enhancement (PAPE) of squat jumps (SJs) and power push-ups (PPUs) following upper body activation, lower body activation, upper and lower body activation, and rest. SJ improved similarly across all 4 conditions. PPU could not be assessed. Since the test protocol of SJ and PPU involved upper and lower body activation and caused PAPE in SJ, future work is required to determine if a nonlocalized PAPE effect exists.

  15. A Survey of Electronic Serials Managers Reveals Diversity in Practice

    Directory of Open Access Journals (Sweden)

    Laura Costello

    2014-09-01

    Full Text Available A Review of: Branscome, B. A. (2013. Management of electronic serials in academic libraries: The results of an online survey. Serials Review, 39(4, 216-226. http://dx.doi.org/10.1016/j.serrev.2013.10.004 Abstract Objective – To examine industry standards for the management of electronic serials and measure the adoption of electronic serials over print. Design – Survey questionnaire. Setting – Email lists aimed at academic librarians working in serials management. Subjects – 195 self-selected subscribers to serials email lists. Methods – The author created a 20 question survey that consisted primarily of closed-ended questions pertaining to the collection demographics, staff, budget, and tools of serials management groups in academic libraries. The survey was conducted via Survey Monkey and examined using the analytical features of the tool. Participants remained anonymous and the survey questions did not ask them to reveal identifiable information about their libraries. Main Results – Collection demographics questions revealed that 78% of surveyed librarians estimated that print-only collections represented 40% or fewer of their serials holdings. The author observed diversity in the factors that influence print to digital transitions in academic libraries. However 71.5% of participants indicated that publisher technology support like IP authentication was required before adopting digital subscriptions. A lack of standardization also marked serials workflows, department responsibilities, and department titles. The author did not find a correlation between serials budget and the enrollment size of the institution. Participants reported that they used tools from popular serials management vendors like Serials Solutions, Innovative Interfaces, EBSCO, and Ex Libris, but most indicated that they used more than one tool for serials management. Participants specified 52 unique serials management products used in their libraries. Conclusion

  16. Gaming is related to enhanced working memory performance and task-related cortical activity.

    Science.gov (United States)

    Moisala, M; Salmela, V; Hietajärvi, L; Carlson, S; Vuontela, V; Lonka, K; Hakkarainen, K; Salmela-Aro, K; Alho, K

    2017-01-15

    Gaming experience has been suggested to lead to performance enhancements in a wide variety of working memory tasks. Previous studies have, however, mostly focused on adult expert gamers and have not included measurements of both behavioral performance and brain activity. In the current study, 167 adolescents and young adults (aged 13-24 years) with different amounts of gaming experience performed an n-back working memory task with vowels, with the sensory modality of the vowel stream switching between audition and vision at random intervals. We studied the relationship between self-reported daily gaming activity, working memory (n-back) task performance and related brain activity measured using functional magnetic resonance imaging (fMRI). The results revealed that the extent of daily gaming activity was related to enhancements in both performance accuracy and speed during the most demanding (2-back) level of the working memory task. This improved working memory performance was accompanied by enhanced recruitment of a fronto-parietal cortical network, especially the dorsolateral prefrontal cortex. In contrast, during the less demanding (1-back) level of the task, gaming was associated with decreased activity in the same cortical regions. Our results suggest that a greater degree of daily gaming experience is associated with better working memory functioning and task difficulty-dependent modulation in fronto-parietal brain activity already in adolescence and even when non-expert gamers are studied. The direction of causality within this association cannot be inferred with certainty due to the correlational nature of the current study. Copyright © 2016 Elsevier B.V. All rights reserved.

  17. Lipidic phase membrane protein serial femtosecond crystallography.

    Science.gov (United States)

    Johansson, Linda C; Arnlund, David; White, Thomas A; Katona, Gergely; Deponte, Daniel P; Weierstall, Uwe; Doak, R Bruce; Shoeman, Robert L; Lomb, Lukas; Malmerberg, Erik; Davidsson, Jan; Nass, Karol; Liang, Mengning; Andreasson, Jakob; Aquila, Andrew; Bajt, Saša; Barthelmess, Miriam; Barty, Anton; Bogan, Michael J; Bostedt, Christoph; Bozek, John D; Caleman, Carl; Coffee, Ryan; Coppola, Nicola; Ekeberg, Tomas; Epp, Sascha W; Erk, Benjamin; Fleckenstein, Holger; Foucar, Lutz; Graafsma, Heinz; Gumprecht, Lars; Hajdu, Janos; Hampton, Christina Y; Hartmann, Robert; Hartmann, Andreas; Hauser, Günter; Hirsemann, Helmut; Holl, Peter; Hunter, Mark S; Kassemeyer, Stephan; Kimmel, Nils; Kirian, Richard A; Maia, Filipe R N C; Marchesini, Stefano; Martin, Andrew V; Reich, Christian; Rolles, Daniel; Rudek, Benedikt; Rudenko, Artem; Schlichting, Ilme; Schulz, Joachim; Seibert, M Marvin; Sierra, Raymond G; Soltau, Heike; Starodub, Dmitri; Stellato, Francesco; Stern, Stephan; Strüder, Lothar; Timneanu, Nicusor; Ullrich, Joachim; Wahlgren, Weixiao Y; Wang, Xiaoyu; Weidenspointner, Georg; Wunderer, Cornelia; Fromme, Petra; Chapman, Henry N; Spence, John C H; Neutze, Richard

    2012-01-29

    X-ray free electron laser (X-FEL)-based serial femtosecond crystallography is an emerging method with potential to rapidly advance the challenging field of membrane protein structural biology. Here we recorded interpretable diffraction data from micrometer-sized lipidic sponge phase crystals of the Blastochloris viridis photosynthetic reaction center delivered into an X-FEL beam using a sponge phase micro-jet.

  18. Infantile Refsum disease: serial evaluation with MRI

    Energy Technology Data Exchange (ETDEWEB)

    Cakirer, Sinan; Savas, Mahmut R. [Sisli Etfal Hospital, Neuroradiology Section, Department of Radiology, Istanbul (Turkey)

    2005-02-01

    Refsum disease is a rare metabolic disorder, which is characterized by the accumulation of phytanic acid in the blood and tissues, including the brain. A variant of this condition that occurs in young children is called infantile Refsum disease. The MRI findings of symmetrical signal change involving the corticospinal tracts, cerebellar dentate nuclei, and corpus callosum are characteristic. We report the serial MRI findings of a child with this rare metabolic disorder. (orig.)

  19. Human pharmacology of a performance-enhancing dietary supplement under resting and exercise conditions

    Science.gov (United States)

    Haller, Christine A; Duan, Minjing; Jacob, Peyton; Benowitz, Neal

    2008-01-01

    AIMS Dietary supplements (DS) promoted to enhance athletic performance often contain herbal sympathomimetics such as Citrus aurantium (synephrine) and caffeine. We aimed to characterize the pharmacology of a performance-enhancing DS in the setting of exercise. METHODS Ten healthy adults (three women) aged 20–31 years participated in a three-arm, double-blind, placebo-controlled, crossover study. Subjects ingested one dose of DS (Ripped Fuel Extreme Cut® with 21 mg synephrine and 304 mg caffeine by analysis) under resting conditions and 1 h prior to moderately intense exercise (30 min on cycle ergometer at 75–80% HRmax), with a placebo (PLC)/exercise control. Plasma synephrine and caffeine concentrations were measured over 12 h, and vital signs, serum electrolytes, oxygen consumption and perceived exercise exertion were monitored. RESULTS No significant adverse events occurred. Synephrine and caffeine pharmacokinetics were unaffected by exercise. Post-exercise diastolic blood pressure was higher after DS (peak mean 71.7 ± 8.7 mmHg) than PLC (63.0 ± 4.9 mmHg) (p = 0.007). There were no substantial treatment-related differences in post-exercise HR, systolic blood pressure, or temperature. Postprandial plasma glucose increased to 121.0 ± 31.6 mg dl−1 with DS and exercise vs. 103.7 ± 25.5 mg dl−1 with PLC and exercise (P = 0.004). No treatment differences in exercise-related oxygen consumption, serum lactate, or insulin were observed. Exercise was rated less difficult with DS than PLC (P = 0.001). CONCLUSIONS Blood pressure and plasma glucose increased post-exercise with DS use, which could be detrimental in some people. Exercise was perceived as less strenuous after DS, presumably due to the stimulant effects of caffeine. WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT Performance-enhancing dietary supplements have not been clinically tested for safety or efficacy. In clinical trials performed under resting conditions, performance-enhancing supplements raise

  20. Plasmonic Enhanced Performance of an Infrared Detector Based on Carbon Nanotube Films.

    Science.gov (United States)

    Huang, Huixin; Wang, Fanglin; Liu, Yang; Wang, Sheng; Peng, Lian-Mao

    2017-04-12

    The carbon nanotube (CNT) has been proved to be a promising material in infrared detection, due to its many advantages of high mobility, strong infrared light absorption, and carrier collection efficiency. However, the absorption restriction from the single layer limits its effective utilization of incident light. In this paper, we introduce a plasmonic electrode structure in a CNT thin-film photodetector based on random deposited high-purity semiconducting CNTs, which can collect photoinduced carriers effectively and enhance light absorption at the same time. The largest enhancement of photocurrents can be achieved at 1650 nm wavelength with suitable plasmonic structure size. Especially, we further discuss the influence of plasmonic structures on the performance of devices. We demonstrate that the best performance improvement of the carbon nanotube detector with plasmonic structure can be enhanced by 13.7 times for photocurrent mode and 5.62 times for photovoltage mode compared to those devices without structure at 1650 nm resonant wavelength. At last, the plasmonic structures are applied on tandem photodetectors with nine virtual contacts, and both the photocurrent and photovoltage are increased. The application of plasmonic electrodes can improve detector performance and retain compact device structures, which shows great potential for optimizing infrared detectors based on nanomaterials.

  1. Performance enhancement of direct ethanol fuel cell using Nafion composites with high volume fraction of titania

    Science.gov (United States)

    Matos, B. R.; Isidoro, R. A.; Santiago, E. I.; Fonseca, F. C.

    2014-12-01

    The present study reports on the performance enhancement of direct ethanol fuel cell (DEFC) at 130 °C with Nafion-titania composite electrolytes prepared by sol-gel technique and containing high volume fractions of the ceramic phase. It is found that for high volume fractions of titania (>10 vol%) the ethanol uptake of composites is largely reduced while the proton conductivity at high-temperatures is weakly dependent on the titania content. Such tradeoff between alcohol uptake and conductivity resulted in a boost of DEFC performance at high temperatures using Nafion-titania composites with high fraction of the inorganic phase.

  2. Enhanced environmental performance of fiber optic gyroscope by an adhesive potting technology.

    Science.gov (United States)

    Chen, Jun; Ding, Nengwen; Li, Zhifeng; Wang, Wei

    2015-09-10

    An adhesive potting technology for fiber coils of a fiber optic gyroscope (FOG) is proposed. The fiber coil is immersed in liquid adhesive with superior mechanical properties. The internal air is first removed completely by vacuum pumping, and the adhesive is then evenly pressed into the fiber coil under pressure. The potted fiber core is prepared by ladder-type temperature curing and a stress-release process. With this potting technology, the vibration performance of an FOG is greatly improved and, at the same time, will not lead to degradation of its temperature performance. Using this potting technique of adhesive impregnation, the adaptability of FOGs will be enhanced.

  3. A High-Performance Parallel FDTD Method Enhanced by Using SSE Instruction Set

    Directory of Open Access Journals (Sweden)

    Dau-Chyrh Chang

    2012-01-01

    Full Text Available We introduce a hardware acceleration technique for the parallel finite difference time domain (FDTD method using the SSE (streaming (single instruction multiple data SIMD extensions instruction set. The implementation of SSE instruction set to parallel FDTD method has achieved the significant improvement on the simulation performance. The benchmarks of the SSE acceleration on both the multi-CPU workstation and computer cluster have demonstrated the advantages of (vector arithmetic logic unit VALU acceleration over GPU acceleration. Several engineering applications are employed to demonstrate the performance of parallel FDTD method enhanced by SSE instruction set.

  4. Enhanced performance of semiconductor optical amplifier at high direct modulation speed with birefringent fiber loop

    Directory of Open Access Journals (Sweden)

    K. E. Zoiros

    2014-07-01

    Full Text Available We employ a birefringent fiber loop (BFL for enhancing the performance of a semiconductor optical amplifier (SOA which is directly modulated. By properly exploiting the BFL comb-like spectral response, we show that the SOA can be directly modulated at a data rate which is more than five times faster than that enabled by the SOA electrical bandwidth. The experimental results, which include chirp measurements, demonstrate the significant improvements achieved in the performance of the directly modulated SOA with the help of the BFL.

  5. Serial CT Findings of Paragonimus Infested Dogs and the Micro-CT Findings of the Worm Cysts

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Chang Hyun; Im, Jung Gi; Goo, Jin Mo; Lee, Hyun Ju; Hong, Sung Tae; Shen, Cheng Hua; Chung, Doo Hyun; Son, Kyu Ri; Chang, Jung Min; Eo, Hong [Seoul National University College of Medicine, Seoul (Korea, Republic of)

    2007-10-15

    To investigate the serial CT findings of Paragonimus westermani infected dogs and the microscopic structures of the worm cysts using Micro-CT. This study was approved by the committee on animal research at our institution. Fifteen dogs infected with P. westermani underwent serial contrast-enhanced CT scans at pre-infection, after 10 days of infection, and monthly thereafter until six months for determining the radiologic-pathologic correlation. Three dogs (one dog each time) were sacrificed at 1, 3 and 6 months, respectively. After fixation of the lungs, both multi-detector CT and Micro-CT were performed for examining the worm cysts. The initial findings were pleural effusion and/or subpleural groundglass opacities or linear opacities at day 10. At day 30, subpleural and peribronchial nodules appeared with hydropneumothorax and abdominal or chest wall air bubbles. Cavitary change and bronchial dilatation began to be seen on CT scan at day 30 and this was mostly seen together with mediastinal lymphadenopathy at day 60. Thereafter, subpleural ground-glass opacities and nodules with or without cavitary changes were persistently observed until day 180. After cavitary change of the nodules, the migratory features of the subpleural or peribronchial nodules were seen on all the serial CT scans. Micro-CT showed that the cyst wall contained dilated interconnected tubular structures, which had communications with the cavity and the adjacent distal bronchus. The CT findings of paragonimiasis depend on the migratory stage of the worms. The worm cyst can have numerous interconnected tubular channels within its own wall and these channels have connections with the cavity and the adjacent distal bronchus.

  6. Benchmarking and performance enhancement framework for multi-staging object-oriented languages

    Directory of Open Access Journals (Sweden)

    Ahmed H. Yousef

    2013-06-01

    Full Text Available This paper focuses on verifying the readiness, feasibility, generality and usefulness of multi-staging programming in software applications. We present a benchmark designed to evaluate the performance gain of different multi-staging programming (MSP languages implementations of object oriented languages. The benchmarks in this suite cover different tests that range from classic simple examples (like matrix algebra to advanced examples (like encryption and image processing. The benchmark is applied to compare the performance gain of two different MSP implementations (Mint and Metaphor that are built on object oriented languages (Java and C# respectively. The results concerning the application of this benchmark on these languages are presented and analysed. The measurement technique used in benchmarking leads to the development of a language independent performance enhancement framework that allows the programmer to select which code segments need staging. The framework also enables the programmer to verify the effectiveness of staging on the application performance. The framework is applied to a real case study. The case study results showed the effectiveness of the framework to achieve significant performance enhancement.

  7. Keeping your cool: possible mechanisms for enhanced exercise performance in the heat with internal cooling methods.

    Science.gov (United States)

    Siegel, Rodney; Laursen, Paul B

    2012-02-01

    Exercising in hot environments results in a rise in core body temperature; an effect associated with impaired performance over a variety of exercise modes and durations. Precooling has become a popular strategy to combat this impairment, as evidence has shown it to be an effective method for lowering pre-exercise core temperature, increasing heat storage capacity and improving exercise performance in the heat. To date, the majority of precooling manoeuvres have been achieved via external means, such as cold water immersion and the application of cooling garments. However, these methods have been criticized for their lack of practicality for use in major sporting competitions. Recent evidence has shown that internal or endogenous cooling methods, such as drinking cold fluids or ice slurries, are able to lower core temperature and enhance endurance performance in the heat. These methods may be more advantageous than current forms of precooling, as ingesting cold fluids or ice slurries can be easily implemented in the field and provide the additional benefit of hydrating athletes. While the precise mechanisms responsible for these performance enhancements are yet to be fully explained, the effect of ice ingestion on brain temperature, internal thermoreception and sensory responses may be involved. This article addresses the evidence supporting the use of endogenous cooling methods for improving endurance performance in the heat, as well as discussing the potential mechanisms behind the improvements observed and providing practical recommendations to optimize their success.

  8. Performance Analysis of enhanced Inter-cell Interference Coordination in LTE-Advanced Heterogeneous Networks

    DEFF Research Database (Denmark)

    Wang, Yuanye; Pedersen, Klaus I.

    2012-01-01

    The performance of enhanced Inter-Cell Interference Coordination (eICIC) for Long Term Evolution (LTE)- Advanced with co-channel deployment of both macro and pico is analyzed. The use of pico-cell Range Extension (RE) and time domain eICIC (TDM muting) is combined. The performance is evaluated...... in the downlink by means of extensive system level simulations that follow the 3GPP guidelines. The overall network performance is analyzed for different number of pico-eNBs, transmit power levels, User Equipment (UE) distributions, and packet schedulers. Recommended settings of the RE offset and TDM muting ratio...... in different scenarios are identified. The presented performance results and findings can serve as input to guidelines for co-channel deployment of macro and pico-eNBs with eICIC....

  9. Serial-Position Effects on a Free-Recall Task in Bilinguals

    OpenAIRE

    Yoo, Jeewon; Kaushanskaya, Margarita

    2015-01-01

    In this study, we examined mechanisms that underlie free-recall performance in bilinguals? first language (L1) and second language (L2) through the prism of serial-position effects. On free-recall tasks, a typical pattern of performance follows a U-shaped serial-position curve, where items from the beginning of the list (the primacy effect) and items from the end of the list (the recency effect) are recalled with higher accuracy than items from the middle of the list. The present study contra...

  10. Enhanced performance in capacitive force sensors using carbon nanotube/polydimethylsiloxane nanocomposites with high dielectric properties

    Science.gov (United States)

    Jang, Hyeyoung; Yoon, Hyungsuk; Ko, Youngpyo; Choi, Jaeyoo; Lee, Sang-Soo; Jeon, Insu; Kim, Jong-Ho; Kim, Heesuk

    2016-03-01

    Force sensors have attracted tremendous attention owing to their applications in various fields such as touch screens, robots, smart scales, and wearable devices. The force sensors reported so far have been mainly focused on high sensitivity based on delicate microstructured materials, resulting in low reproducibility and high fabrication cost that are limitations for wide applications. As an alternative, we demonstrate a novel capacitive-type force sensor with enhanced performance owing to the increased dielectric properties of elastomers and simple sensor structure. We rationally design dielectric elastomers based on alkylamine modified-multi-walled carbon nanotube (MWCNT)/polydimethylsiloxane (PDMS) composites, which have a higher dielectric constant than pure PDMS. The alkylamine-MWCNTs show excellent dispersion in a PDMS matrix, thus leading to enhanced and reliable dielectric properties of the composites. A force sensor array fabricated with alkylamine-MWCNT/PDMS composites presents an enhanced response due to the higher dielectric constant of the composites than that of pure PDMS. This study is the first to report enhanced performance of capacitive force sensors by modulating the dielectric properties of elastomers. We believe that the disclosed strategy to improve the sensor performance by increasing the dielectric properties of elastomers has great potential in the development of capacitive force sensor arrays that respond to various input forces.Force sensors have attracted tremendous attention owing to their applications in various fields such as touch screens, robots, smart scales, and wearable devices. The force sensors reported so far have been mainly focused on high sensitivity based on delicate microstructured materials, resulting in low reproducibility and high fabrication cost that are limitations for wide applications. As an alternative, we demonstrate a novel capacitive-type force sensor with enhanced performance owing to the increased

  11. Internal Flow Simulation of Enhanced Performance Solid Rocket Booster for the Space Transportation System

    Science.gov (United States)

    Ahmad, Rashid A.; McCool, Alex (Technical Monitor)

    2001-01-01

    An enhanced performance solid rocket booster concept for the space shuttle system has been proposed. The concept booster will have strong commonality with the existing, proven, reliable four-segment Space Shuttle Reusable Solid Rocket Motors (RSRM) with individual component design (nozzle, insulator, etc.) optimized for a five-segment configuration. Increased performance is desirable to further enhance safety/reliability and/or increase payload capability. Performance increase will be achieved by adding a fifth propellant segment to the current four-segment booster and opening the throat to accommodate the increased mass flow while maintaining current pressure levels. One development concept under consideration is the static test of a "standard" RSRM with a fifth propellant segment inserted and appropriate minimum motor modifications. Feasibility studies are being conducted to assess the potential for any significant departure in component performance/loading from the well-characterized RSRM. An area of concern is the aft motor (submerged nozzle inlet, aft dome, etc.) where the altered internal flow resulting from the performance enhancing features (25% increase in mass flow rate, higher Mach numbers, modified subsonic nozzle contour) may result in increased component erosion and char. To assess this issue and to define the minimum design changes required to successfully static test a fifth segment RSRM engineering test motor, internal flow studies have been initiated. Internal aero-thermal environments were quantified in terms of conventional convective heating and discrete phase alumina particle impact/concentration and accretion calculations via Computational Fluid Dynamics (CFD) simulation. Two sets of comparative CFD simulations of the RSRM and the five-segment (IBM) concept motor were conducted with CFD commercial code FLUENT. The first simulation involved a two-dimensional axi-symmetric model of the full motor, initial grain RSRM. The second set of analyses

  12. From animal cruelty to serial murder: applying the graduation hypothesis.

    Science.gov (United States)

    Wright, Jeremy; Hensley, Christopher

    2003-02-01

    Although serial murder has been recorded for centuries, limited academic attention has been given to this important topic. Scholars have attempted to examine the causality and motivations behind the rare phenomenon of serial murder. However, scant research exists which delves into the childhood characteristics of serial murderers. Using social learning theory, some of these studies present supporting evidence for a link between childhood animal cruelty and adult aggression toward humans. Based on five case studies of serial murderers, we contribute to the existing literature by exploring the possible link between childhood cruelty toward animals and serial murder with the application of the graduation hypothesis.

  13. Hardware Implementation of Serially Concatenated PPM Decoder

    Science.gov (United States)

    Moision, Bruce; Hamkins, Jon; Barsoum, Maged; Cheng, Michael; Nakashima, Michael

    2009-01-01

    A prototype decoder for a serially concatenated pulse position modulation (SCPPM) code has been implemented in a field-programmable gate array (FPGA). At the time of this reporting, this is the first known hardware SCPPM decoder. The SCPPM coding scheme, conceived for free-space optical communications with both deep-space and terrestrial applications in mind, is an improvement of several dB over the conventional Reed-Solomon PPM scheme. The design of the FPGA SCPPM decoder is based on a turbo decoding algorithm that requires relatively low computational complexity while delivering error-rate performance within approximately 1 dB of channel capacity. The SCPPM encoder consists of an outer convolutional encoder, an interleaver, an accumulator, and an inner modulation encoder (more precisely, a mapping of bits to PPM symbols). Each code is describable by a trellis (a finite directed graph). The SCPPM decoder consists of an inner soft-in-soft-out (SISO) module, a de-interleaver, an outer SISO module, and an interleaver connected in a loop (see figure). Each SISO module applies the Bahl-Cocke-Jelinek-Raviv (BCJR) algorithm to compute a-posteriori bit log-likelihood ratios (LLRs) from apriori LLRs by traversing the code trellis in forward and backward directions. The SISO modules iteratively refine the LLRs by passing the estimates between one another much like the working of a turbine engine. Extrinsic information (the difference between the a-posteriori and a-priori LLRs) is exchanged rather than the a-posteriori LLRs to minimize undesired feedback. All computations are performed in the logarithmic domain, wherein multiplications are translated into additions, thereby reducing complexity and sensitivity to fixed-point implementation roundoff errors. To lower the required memory for storing channel likelihood data and the amounts of data transfer between the decoder and the receiver, one can discard the majority of channel likelihoods, using only the remainder in

  14. Enhanced performance in electrochemical energy storage and conversion via carbon-integrated nanostructures

    Science.gov (United States)

    Sheehan, Margaret K.

    Electrochemical energy storage and conversion applications benefit from the integration of nanostructures into the devices, as they have many more active sites per gram which enables excellent mass utilization of the active species. By controlling the surface of fuel cell catalysts, higher activity and efficiency can be achieved as compared to the bulk counterpart, with multiple catalyst facets of varying activity and efficiency. Nanostructured electrochemical capacitors have enhanced electrolyte diffusion over the surface of the electrode, facilitating high rate capability. Nanostructured materials for energy storage and conversion devices, such as electrochemical capacitors and proton exchange membrane fuel cells, can perform even better with the incorporation of carbon. High surface area carbon can enhance the activity of electrochemical capacitors by improving the conductivity of the electrode and/or enhancing the double layer capacitance. Carbon supports for fuel cell catalysts enable proper dispersion of active material without sacrificing conductivity. The work reported in this thesis is aimed toward improving the performance of electrochemical energy storage and conversion devices through novel incorporation of carbon. Carbon was first used to enhance the performance of electrocatalysts. By wrapping fuel cell catalysts in a porous carbon shell, the activity was increased over its bare and CNT-supported counterparts. The carbon shell synthetic method reported here is a good route to the production of a conductive host for Pd electrocatalysts with good contact and in one step with the formation of the Pd nanoparticles. Carbon was also used to enhance the performance of pseudocapacitors, first by incorporating it into the precursor spray solution in the generation of mesoporous metal oxides and then as a metal-organic framework-derived carbon host with dispersed electrochemically active metal oxides. A carbon network was generated from the pyrolysis of pore

  15. Enhanced performance of microbial fuel cell with a bacteria/multi-walled carbon nanotube hybrid biofilm

    Science.gov (United States)

    Zhang, Peng; Liu, Jia; Qu, Youpeng; Zhang, Jian; Zhong, Yingjuan; Feng, Yujie

    2017-09-01

    The biofilm on the anode of a microbial fuel cell (MFC) is a vital component in system, and its formation and characteristic determines the performance of the system. In this study, a bacteria/Multi-Walled Carbon Nanotube (MWCNT) hybrid biofilm is fabricated by effectively inserting the MWCNTs into the anode biofilm via an adsorption-filtration method. This hybrid biofilm has been demonstrated to be an efficient structure for improving an anode biofilm performance. Electrochemical impedance spectroscopy (EIS) results show that the hybrid biofilm takes advantage of the conductivity and structure of MWCNT to enhance the electron transfer and substrate diffusion of the biofilm. With this hybrid biofilm, the current density, power density and coulombic efficiency are increased by 46.2%, 58.8% and 84.6%, respectively, relative to naturally grown biofilm. Furthermore, the start-up time is reduced by 53.8% compared with naturally grown biofilm. The perturbation test demonstrates that this type of hybrid biofilm exhibits strong adsorption ability and enhances the biofilm's resistance to a sudden change of substrate concentration. The superior performance of the hybrid biofilm with MWCNT ;nanowire; matrix compared with naturally grown biofilm demonstrates its great potential for boosting the performance of MFCs.

  16. Performance Evaluation of an Enhanced Uplink 3.5G System for Mobile Healthcare Applications.

    Science.gov (United States)

    Komnakos, Dimitris; Vouyioukas, Demosthenes; Maglogiannis, Ilias; Constantinou, Philip

    2008-01-01

    The present paper studies the prospective and the performance of a forthcoming high-speed third generation (3.5G) networking technology, called enhanced uplink, for delivering mobile health (m-health) applications. The performance of 3.5G networks is a critical factor for successful development of m-health services perceived by end users. In this paper, we propose a methodology for performance assessment based on the joint uplink transmission of voice, real-time video, biological data (such as electrocardiogram, vital signals, and heart sounds), and healthcare records file transfer. Various scenarios were concerned in terms of real-time, nonreal-time, and emergency applications in random locations, where no other system but 3.5G is available. The accomplishment of quality of service (QoS) was explored through a step-by-step improvement of enhanced uplink system's parameters, attributing the network system for the best performance in the context of the desired m-health services.

  17. Adaptive luminance contrast for enhancing reading performance and visual comfort on smartphone displays

    Science.gov (United States)

    Na, Nooree; Suk, Hyeon-Jeong

    2014-11-01

    This study developed a model for setting the adaptive luminance contrast between text and background for enhancing reading performance and visual comfort on smartphone displays. The study was carried out in two experiments. In Experiment I, a user test was conducted to identify the optimal luminance contrast with regard to subjects' reading performance, measured by lines of text reading and visual comfort, assessed by self-report after the reading. Based on the empirical results of the test, an ideal adaptive model which decreases the luminance contrast gradually with passage of time was developed. In Experiment II, a validation test involving reading performance, visual comfort, and physiological stress measured by a brainwave analysis using an electroencephalogram confirmed that the proposed adaptive luminance contrast is adequate for prolonged text reading on smartphone displays. The developed model enhances both reading performance and visual comfort as well as reduces the energy consumption of a smartphone; hence, it is expected that this study will be applied to diverse kinds of visual display terminals.

  18. A novel and practical approach to distribution system performance enhancement using a fuzzy capacitor allocation method

    Science.gov (United States)

    Ng, Hok-Nin

    As the electrical utility business enters into a deregulated environment, distribution companies will strive to operate at the utmost economic efficiency. Loss reduction through the use of capacitor placement is an effective means of decreasing the operating costs of a utility. This thesis details a practical and flexible approach for distribution system loss reduction and performance enhancement using a fuzzy capacitor allocation technique. The proposed method takes advantage of the concepts of fuzzy set theory to model uncertain parameters of the distribution system, and to represent knowledge and heuristics that can be used to optimize the operation of the distribution system. A fuzzy expert system is used to determine suitable locations for capacitor installations and a multi-objective fuzzy optimization approach is used to determine the proper sizes of the capacitors. Effective control of capacitors is performed by another fuzzy expert system. Computer simulations performed, have clearly demonstrated the advantages and the significant contributions of the methods in this thesis for distribution system loss reduction and performance enhancement.

  19. Enhancement of multitasking performance and neural oscillations by transcranial alternating current stimulation.

    Science.gov (United States)

    Hsu, Wan-Yu; Zanto, Theodore P; van Schouwenburg, Martine R; Gazzaley, Adam

    2017-01-01

    Multitasking is associated with the generation of stimulus-locked theta (4-7 Hz) oscillations arising from prefrontal cortex (PFC). Transcranial alternating current stimulation (tACS) is a non-invasive brain stimulation technique that influences endogenous brain oscillations. Here, we investigate whether applying alternating current stimulation within the theta frequency band would affect multitasking performance, and explore tACS effects on neurophysiological measures. Brief runs of bilateral PFC theta-tACS were applied while participants were engaged in a multitasking paradigm accompanied by electroencephalography (EEG) data collection. Unlike an active control group, a tACS stimulation group showed enhancement of multitasking performance after a 90-minute session (F1,35 = 6.63, p = 0.01, ηp2 = 0.16; effect size = 0.96), coupled with significant modulation of posterior beta (13-30 Hz) activities (F1,32 = 7.66, p = 0.009, ηp2 = 0.19; effect size = 0.96). Across participant regression analyses indicated that those participants with greater increases in frontal theta, alpha and beta oscillations exhibited greater multitasking performance improvements. These results indicate frontal theta-tACS generates benefits on multitasking performance accompanied by widespread neuronal oscillatory changes, and suggests that future tACS studies with extended treatments are worth exploring as promising tools for cognitive enhancement.

  20. Using noninvasive brain stimulation to accelerate learning and enhance human performance.

    Science.gov (United States)

    Parasuraman, Raja; McKinley, Richard A

    2014-08-01

    The authors evaluate the effectiveness of noninvasive brain stimulation, in particular, transcranial direct current stimulation (tDCS), for accelerating learning and enhancing human performance on complex tasks. Developing expertise in complex tasks typically requires extended training and practice. Neuroergonomics research has suggested new methods that can accelerate learning and boost human performance. TDCS is one such method. It involves the application of a weak DC current to the scalp and has the potential to modulate brain networks underlying the performance of a perceptual, cognitive, or motor task. Examples of tDCS studies of declarative and procedural learning are discussed. This mini-review focuses on studies employing complex simulations representative of surveillance and security operations, intelligence analysis, and procedural learning in complex monitoring. The evidence supports the view that tDCS can accelerate learning and enhance performance in a range of complex cognitive tasks. Initial findings also suggest that such benefits can be retained over time, but additional research is needed on training schedules and transfer of training. Noninvasive brain stimulation can accelerate skill acquisition in complex tasks and may provide an alternative or addition to other training methods.