Long-Term Memory for Knowledge Learned in School.

ERIC Educational Resources Information Center

Semb, George B.; And Others

1993-01-01

Three experiments (initial total sample of 190 college students) examined students' long-term retention of knowledge learned in college courses. Results of all experiments suggest that students remember a great deal of what they learn up to 11 months later and that tutoring has positive effects on recall by tutors. (SLD)

Speaking rate affects the perception of duration as a suprasegmental lexical-stress cue.

PubMed

Reinisch, Eva; Jesse, Alexandra; McQueen, James M

2011-06-01

Three categorization experiments investigated whether the speaking rate of a preceding sentence influences durational cues to the perception of suprasegmental lexical-stress patterns. Dutch two-syllable word fragments had to be judged as coming from one of two longer words that matched the fragment segmentally but differed in lexical stress placement. Word pairs contrasted primary stress on either the first versus the second syllable or the first versus the third syllable. Duration of the initial or the second syllable of the fragments and rate of the preceding context (fast vs. slow) were manipulated. Listeners used speaking rate to decide about the degree of stress on initial syllables whether the syllables' absolute durations were informative about stress (Experiment Ia) or not (Experiment Ib). Rate effects on the second syllable were visible only when the initial syllable was ambiguous in duration with respect to the preceding rate context (Experiment 2). Absolute second syllable durations contributed little to stress perception (Experiment 3). These results suggest that speaking rate is used to disambiguate words and that rate-modulated stress cues are more important on initial than noninitial syllables. Speaking rate affects perception of suprasegmental information.

Interference of the end: why recency bias in memory determines when a food is consumed again.

PubMed

Garbinsky, Emily N; Morewedge, Carey K; Shiv, Baba

2014-07-01

The results of three experiments reveal that memory for end enjoyment, rather than beginning enjoyment, of a pleasant gustatory experience determines how soon people desire to repeat that experience. We found that memory for end moments, when people are most satiated, interferes with memory for initial moments. Consequently, end moments are more influential than initial moments when people decide how long to wait until consuming a food again. The findings elucidate the role of memory in delay until repeated consumption, demonstrate how sensory-specific satiety and portion sizes influence future consumption, and suggest one process by which recency effects influence judgments and decisions based on past experiences. © The Author(s) 2014.

Does representational momentum reflect a distortion of the length or the endpoint of a trajectory?

PubMed

Hubbard, Timothy L; Motes, Michael A

2002-01-01

Observers viewed a moving target, and after the target vanished, indicated either the initial position or the final position of the target. In Experiment 1, an auditory tone cued observers to indicate either the initial position or the final position; in Experiment 2, different groups of observers indicated the initial position or the final position. Judgments of the initial position were displaced backward in the direction opposite to motion, and judgments of the final position were displaced forward in the direction of motion. The data suggest that the remembered trajectory is longer than the actual trajectory, and the displacement pattern is not consistent with the hypothesis that representational momentum results from a distortion of memory for the location of a trajectory.

The Dark Side of Testing Memory: Repeated Retrieval Can Enhance Eyewitness Suggestibility

ERIC Educational Resources Information Center

Chan, Jason C. K.; LaPaglia, Jessica A.

2011-01-01

Eyewitnesses typically recount their experiences many times before trial. Such repeated retrieval can enhance memory retention of the witnessed event. However, recent studies (e.g., Chan, Thomas, & Bulevich, 2009) have found that initial retrieval can exacerbate eyewitness suggestibility to later misleading information--a finding termed…

Fatigue-Induced Damage in Zr-Based Bulk Metallic Glasses

PubMed Central

Chuang, Chih-Pin; Yuan, Tao; Dmowski, Wojciech; Wang, Gong-Yao; Freels, Matt; Liaw, Peter K.; Li, Ran; Zhang, Tao

2013-01-01

In the present work, we investigate the effect of “fatigue” on the fatigue behavior and atomic structure of Zr-based BMGs. Fatigue experiments on the failed-by-fatigue samples indicate that the remnants generally have similar or longer fatigue life than the as-cast samples. Meanwhile, the pair-distribution-function (PDF) analysis of the as-cast and post-fatigue samples showed very small changes of local atomic structures. These observations suggest that the fatigue life of the 6-mm in-diameter Zr-based BMG is dominated by the number of pre-existing crack-initiation sites in the sample. Once the crack initiates in the specimen, the fatigue-induced damage is accumulated locally on these initiated sites, while the rest of the region deforms elastically. The results suggest that the fatigue failure of BMGs under compression-compression fatigue experiments is a defect-controlled process. The present work indicates the significance of the improved fatigue resistance with decreasing the sample size. PMID:23999496

Wild Beginnings: How a San Antonio Initiative Instills the Love of Nature in Young Children

ERIC Educational Resources Information Center

Kharod, Deepti; Arreguín-Anderson, Maria G.

2015-01-01

This paper describes an environmental education initiative called Starting out Wild (SoW) designed for toddlers and their caretakers. The program, developed by staff and volunteers of a city parks department, engages children ages 1-3 and their parents and caretakers through outdoor learning experiences. We suggest that environmental education…

An investigation of phonology and orthography in spoken-word recognition.

PubMed

Slowiaczek, Louisa M; Soltano, Emily G; Wieting, Shani J; Bishop, Karyn L

2003-02-01

The possible influence of initial phonological and/or orthographic information on spoken-word processing was examined in six experiments modelled after and extending the work Jakimik, Cole, and Rudnicky (1985). Following Jakimik et al., Experiment 1 used polysyllabic primes with monosyllabic targets (e.g., BUCKLE-BUCK/[symbol: see text]; MYSTERY-MISS,/[symbol: see text]). Experiments 2, 3, and 4 used polysyllabic primes and polysyllabic targets whose initial syllables shared phonological information (e.g., NUISANCE-NOODLE,/[symbol: see text]), orthographic information (e.g., RATIO-RATIFY,/[symbol: see text]), both (e.g., FUNNEL-FUNNY,/[symbol: see text]), or were unrelated (e.g., SERMON-NOODLE,/[symbol: see text]). Participants engaged in a lexical decision (Experiments 1, 3, and 4) or a shadowing (Experiment 2) task with a single-trial (Experiments 2 and 3) or subsequent-trial (Experiments 1 and 4) priming procedure. Experiment 5 tested primes and targets that varied in the number of shared graphemes while holding shared phonemes constant at one. Experiment 6 used the procedures of Experiment 2 but a low proportion of related trials. Results revealed that response times were facilitated for prime-target pairs that shared initial phonological and orthographic information. These results were confirmed under conditions when strategic processing was greatly reduced suggesting that phonological and orthographic information is automatically activated during spoken-word processing.

The Impact of a History of Adverse Childhood Experiences on Breastfeeding Initiation and Exclusivity: Findings from a National Population Health Survey.

PubMed

Ukah, Ugochinyere Vivian; Adu, Prince A; De Silva, Dane A; von Dadelszen, Peter

2016-12-01

Exclusive breastfeeding is strongly recommended by the World Health Organization. Given the low rate of exclusive breastfeeding in Canada and the increasing reports of a history of adverse childhood experiences, this study sought to investigate the association between a history of adverse childhood experiences and breastfeeding initiation and breastfeeding. Data used for this study were based on the 2011-2012 Canadian Community Health Survey, collected using a cross-sectional survey. The outcome measures were breastfeeding initiation and exclusive breastfeeding for 6 months or more. History of adverse childhood experiences was the main explanatory variable. Multivariable logistic regression models were developed to investigate the effect on breastfeeding initiation and on exclusive breastfeeding in women who gave birth within 5 years before when the surveys were conducted. The study sample included 697 and 633 women for analyses on breastfeeding initiation and breastfeeding, respectively. The proportion of women with breastfeeding initiation and exclusive breastfeeding for up to 6 months in this study were 96.8% and 42.8%, respectively. After controlling for age and highest level of education, having a history of adverse childhood experiences was not significantly associated with breastfeeding initiation (odds ratio [OR] 0.46, 95% confidence interval [CI] 0.10-1.87), but mothers with such history were less likely to exclusively breastfeed for up to 6 months compared with those without (OR 0.53, 95% CI 0.31-0.90). These findings suggest the need for more breastfeeding monitoring programs beyond the hospital environment to provide more support to Canadian mothers, especially those who have experienced adverse childhood experiences or trauma in the past.

Boreal Summer ISO hindcast experiment: preliminary results from SNU

NASA Astrophysics Data System (ADS)

Heo, S.; Kang, I.; Kim, D.; Ham, Y.

2010-12-01

As a part of internationally coordinated research program, hindcast experiments with focus on boreal summer intraseasonal oscillation (ISO) have been done in Seoul National University (SNU). This study aims to show preliminary results from SNU’s efforts. The ISO prediction system used in the hindcast experiment consists of SNU coupled model and SNU initialization method. The SNU coupled model is an ocean-atmosphere coupled model which couples the SNU Atmospheric GCM (SNU AGCM) to the Modular Ocean Model ver.2.2 (MOM2.2) Ocean GCM developed at Geophysical Fluid Dynamics Laboratory (GFDL). In the SNU initialization method, both atmospheric and oceanic states are nudged toward reanalysis data (ERAinterim and GODAS) before prediction starting date. For the results here, 2 ensemble members are generated by using different nudging period, 8 and 9 days, respectively. The initial dates of 45-day predictions are the 1st, 11th, 21st of months during boreal summer season (May to October). Prediction skills and its dependency on the initial amplitude, the initial phase, and the number of ensemble members are investigated using the Real-time Multivariate MJO (RMM) index suggested by Wheeler and Hendon (2004). It is shown in our hindcast experiment that, after 13 forecast lead days (the forecast skill is about 0.7), the prediction skill does not depend on the strength of the initial state. Also, we found that the prediction skill has a phase dependency. The prediction skill is particularly low when the convective center related to the MJO is over the Indian Ocean (phase 2). The ensemble prediction has more improved correlation skill than each member. To better understand the phase dependency, we compared the observed and predicted behavior of the MJO that propagates from different starting phases. The phase speed of the prediction is slower than the observation. The MJO in the hindcast experiment propagates with weaker amplitudes than observed except for initial phase 3. Also investigated is the climatology and anomalies of precipitable water to understand the difference of the propagation. The difference between observed and predicted climatology shows strong dry bias over the eastern Indian Ocean, in where convective anomalies are not properly developed in hindcast data, especially those from initial phase 2. Our results suggest possible impacts of mean bias on prediction skills of the MJO.

Initialization and Predictability of a Coupled ENSO Forecast Model

NASA Technical Reports Server (NTRS)

Chen, Dake; Zebiak, Stephen E.; Cane, Mark A.; Busalacchi, Antonio J.

1997-01-01

The skill of a coupled ocean-atmosphere model in predicting ENSO has recently been improved using a new initialization procedure in which initial conditions are obtained from the coupled model, nudged toward observations of wind stress. The previous procedure involved direct insertion of wind stress observations, ignoring model feedback from ocean to atmosphere. The success of the new scheme is attributed to its explicit consideration of ocean-atmosphere coupling and the associated reduction of "initialization shock" and random noise. The so-called spring predictability barrier is eliminated, suggesting that such a barrier is not intrinsic to the real climate system. Initial attempts to generalize the nudging procedure to include SST were not successful; possible explanations are offered. In all experiments forecast skill is found to be much higher for the 1980s than for the 1970s and 1990s, suggesting decadal variations in predictability.

The Role of Learning Support in Open & Distance Learning: Learners' Experiences and Perspectives

ERIC Educational Resources Information Center

Dzakiria, Hisham

2005-01-01

This qualitative study reports in some detail the experience of a small group of distance learners as they progress through their courses at Universiti Utara Malaysia (UUM). An initial literature review suggested that while a number of studies had been completed in the past two decades that report student characteristics, motivations, and prior…

The effects of initial testing on false recall and false recognition in the social contagion of memory paradigm.

PubMed

Huff, Mark J; Davis, Sara D; Meade, Michelle L

2013-08-01

In three experiments, participants studied photographs of common household scenes. Following study, participants completed a category-cued recall test without feedback (Exps. 1 and 3), a category-cued recall test with feedback (Exp. 2), or a filler task (no-test condition). Participants then viewed recall tests from fictitious previous participants that contained erroneous items presented either one or four times, and then completed final recall and source recognition tests. The participants in all conditions reported incorrect items during final testing (a social contagion effect), and across experiments, initial testing had no impact on false recall of erroneous items. However, on the final source-monitoring recognition test, initial testing had a protective effect against false source recognition: Participants who were initially tested with and without feedback on category-cued initial tests attributed fewer incorrect items to the original event on the final source-monitoring recognition test than did participants who were not initially tested. These data demonstrate that initial testing may protect individuals' memories from erroneous suggestions.

Auxin fluxes in the root apex co-regulate gravitropism and lateral root initiation.

PubMed

Lucas, M; Godin, C; Jay-Allemand, C; Laplaze, L

2008-01-01

Root architecture plays an important role in water and nutrient acquisition and in the ability of the plant to adapt to the soil. Lateral root development is the main determinant of the shape of the root system and is controlled by external factors such as nutrient concentration. Here it is shown that lateral root initiation and root gravitropism, two processes that are regulated by auxin, are co-regulated in Arabidopsis. A mathematical model was generated that can predict the effects of gravistimulations on lateral root initiation density and suggests that lateral root initiation is controlled by an inhibitory fields mechanism. Moreover, gene transactivation experiments suggest a mechanism involving a single auxin transport route for both responses. Finally, co-regulation may offer a selective advantage by optimizing soil exploration as supported by a simple quantitative analysis.

Will Arctic sea ice thickness initialization improve seasonal forecast skill?

NASA Astrophysics Data System (ADS)

Day, J. J.; Hawkins, E.; Tietsche, S.

2014-11-01

Arctic sea ice thickness is thought to be an important predictor of Arctic sea ice extent. However, coupled seasonal forecast systems do not generally use sea ice thickness observations in their initialization and are therefore missing a potentially important source of additional skill. To investigate how large this source is, a set of ensemble potential predictability experiments with a global climate model, initialized with and without knowledge of the sea ice thickness initial state, have been run. These experiments show that accurate knowledge of the sea ice thickness field is crucially important for sea ice concentration and extent forecasts up to 8 months ahead, especially in summer. Perturbing sea ice thickness also has a significant impact on the forecast error in Arctic 2 m temperature a few months ahead. These results suggest that advancing capabilities to observe and assimilate sea ice thickness into coupled forecast systems could significantly increase skill.

Oculomotor Evidence for Top-Down Control following the Initial Saccade

PubMed Central

Siebold, Alisha; van Zoest, Wieske; Donk, Mieke

2011-01-01

The goal of the current study was to investigate how salience-driven and goal-driven processes unfold during visual search over multiple eye movements. Eye movements were recorded while observers searched for a target, which was located on (Experiment 1) or defined as (Experiment 2) a specific orientation singleton. This singleton could either be the most, medium, or least salient element in the display. Results were analyzed as a function of response time separately for initial and second eye movements. Irrespective of the search task, initial saccades elicited shortly after the onset of the search display were primarily salience-driven whereas initial saccades elicited after approximately 250 ms were completely unaffected by salience. Initial saccades were increasingly guided in line with task requirements with increasing response times. Second saccades were completely unaffected by salience and were consistently goal-driven, irrespective of response time. These results suggest that stimulus-salience affects the visual system only briefly after a visual image enters the brain and has no effect thereafter. PMID:21931603

Infidelity, initiation, and the emotional climate of divorce: are there implications for mental health?

PubMed

Sweeney, M M; Horwitz, A V

2001-09-01

A large literature has examined the role of "secondary" stressors, such as problems with finances, social support, residential mobility, and children, in producing the well-documented association between divorce and a variety of psychopathological conditions. Much less attention, however, has been paid to variation in the "primary" disruption experience. We address this omission using data from the National Survey of Families and Households to investigate the interrelationships among depression, initiator status, and spousal infidelity. While we find little evidence of direct effects of initiator status or spousal infidelity on post-divorce depression, the importance of these characteristics emerges when they are considered in an interactive context. Specifically, while divorce initiation is associated with reduced depression among individuals with unfaithful spouses, initiation is associated with increased depression in the absence of spousal infidelity. Taken together, our findings suggest that characteristics of the divorce experience may interact in complex ways to produce variation in mental health outcomes.

Effects of prior aversive experience upon retrograde amnesia induced by hypothermia.

PubMed

Jensen, R A; Riccio, D C; Gehres, L

1975-08-01

Two experiments examined the extent to which retrograde amnesia (RA) is attenuated by prior learning experiences. In Experiment 1, rats initially received either passive avoidance training in a step-through apparatus, exposure to the apparatus, or noncontingent footshock. When training on a second but different passive avoidance task was followed by hypothermia treatment, RA was obtained only in the latter two groups. In Experiment 2, one-way active avoidance training, yoked noncontingent shocks, or apparatus exposure constituted the initial experience. Subsequent step-down passive avoidance training and amnestic treatment resulted in memory loss for the prior apparatus exposure group, but not for either of the preshocked conditions. These experiments demonstrate that certain types of prior aversive experience can substantially modify the magnitude of RA, and, in conjunction with other familiarization studies, emphasize a paradox for interpretations of RA based solely upon CNS disruption. The possibility that hypothermia treatment serves as an important contextual or encoding cue necessary for memory retrieval was considered. It was suggested that prior experience may block RA by enabling rats to differentiate training and treatment conditions.

The impact of the Baby Friendly Health Initiative in the Australian health care system: a critical narrative review of the evidence.

PubMed

Atchan, Marjorie; Davis, Deborah; Foureur, Maralyn

2013-07-01

Studies have identified that the practices of maternity facilities and health professionals are crucial to women's experience of support and breastfeeding 'success'. The Baby Friendly Hospital Initiative (BFHI) was launched globally in 1991 to protect, promote and support breastfeeding. While a direct causal effect has not been established and critics suggest the rhetoric conflicts with women's lived experiences as new mothers, a positive association between the Initiative and breastfeeding prevalence is apparent. Internationally, impact studies have demonstrated that where the Initiative is well integrated, there is an increase in rates of breastfeeding initiation and, to a lesser extent, duration. In consideration of the known health risks associated with the use of artificial baby milks this would suggest that BFHI implementation and accreditation should be a desirable strategy for committed health facilities. However, a variation in both BFHI uptake and breastfeeding prevalence between nations has been reported. This narrative review critically discusses a variety of issues relevant to the uptake and support of breastfeeding and the BFHI, utilising Australia as a case study. Whilst it enjoys 'in principle' policy support, Australia also suffers from a lack of uniformity in uptake and perception of the benefits of BFHI at all levels of the health system. Australian and international studies have identified similar enablers and barriers to implementation.

Differences in Subjective Experiences to First Use of Menthol and Non-Menthol Cigarettes in a National Sample of Young Adult Cigarette Smokers.

PubMed

D'Silva, Joanne; Cohn, Amy M; Johnson, Amanda L; Villanti, Andrea C

2017-08-17

Menthol has been hypothesized to ease the harshness of cigarette smoke. Thus, sensory experiences at first cigarette use may be one mechanism by which menthol facilitates progression to regular smoking. This study examined differences in subjective experiences to first use of a menthol vs. non-menthol cigarette among new young adult smokers. Data were drawn from Waves 5-8 of the Truth Initiative Young Adult Cohort Study, a national sample of 18-34 year olds assessed every six months. Analyses included a subset of young adult current smokers (n=251) who initiated smoking in the past six months. Subjective responses to first cigarette use were assessed across menthol and non-menthol initiators in bivariate analyses and adjusted models controlling for smoking correlates. Fifty-two percent of new young adult smokers used a menthol cigarette at first use. First use of a menthol cigarette was higher in those aged 18-24 (vs. 25-34). Most Black smokers (93.1%) were menthol initiators compared to 43.9% of White smokers. More than half of menthol and non-menthol initiates felt relaxed or calm, dizzy, lightheaded, liking the taste and a rush or buzz at first use. Menthol initiators were less likely in bivariate and multivariable analyses to experience feeling nauseated at first use (AOR=0.45; p=.020) compared to non-menthol initiators. While few differences were found between menthol and non-menthol initiators in their subjective experiences, fewer menthol initiates felt nauseated at first cigarette use. Future research needs to identify additional mechanisms linking menthol initiation to smoking progression. Menthol initiators were more likely to be younger (18-24 vs. 25-34) and Black (vs. White) compared to non-menthol initiators. Our finding that menthol initiators were less likely to feel nauseated at first cigarette use compared to non-menthol initiators, suggests that menthol may reduce aversion to early cigarette use among young smokers and thus has the potential to facilitate continued experimentation. Interventions and policy approaches to reduce tobacco use initiation and progression are urgently needed in young people. © The Author 2017. Published by Oxford University Press on behalf of the Society for Research on Nicotine and Tobacco. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Creating unstable velocity-space distributions with barium injections

NASA Technical Reports Server (NTRS)

Pongratz, M. B.

1983-01-01

Ion velocity-space distributions resulting from barium injections from orbiting spacecraft and shaped charges are discussed. Active experiments confirm that anomalous ionization processes may operate, but photoionization accounts for the production of the bulk of the barium ions. Pitch-angle diffusion and/or velocity-space diffusion may occur, but observations of barium ions moving upwards against gravity suggests that the ions retain a significant enough fraction of their initial perpendicular velocity to provide a mirror force. The barium ion plasmas should have a range of Alfven Mach numbers and plasma betas. Because the initial conditions can be predicted these active experiments should permit testing plasma instability hypotheses.

Intense and recurrent déjà vu experiences related to amantadine and phenylpropanolamine in a healthy male.

PubMed

Taiminen, T; Jääskeläinen, S K

2001-09-01

We report a case of a 39-year-old caucasian healthy male physician who developed intense and recurrent déjà vu experiences within 24h of initiating concomitant amantadine-phenylpropanolamine treatment against influenza. Déjà vu experiences terminated on discontinuation of medication. Findings in temporal epilepsy suggest that mesial temporal structures, including hippocampus, are related to paramnesic symptoms. On the other hand, previous case reports have confirmed that both amantadine and phenylpropanolamine alone, and particularly in combination, can induce psychotic symptoms due to their dopaminergic activity. The authors suggest that déjà vu experiences may be provoked by increased dopamine activity in mesial temporal structures of the brain. Copyright 2001 Harcourt Publishers Ltd.

Adverse childhood experiences and the association with ever using alcohol and initiating alcohol use during adolescence.

PubMed

Dube, Shanta R; Miller, Jacqueline W; Brown, David W; Giles, Wayne H; Felitti, Vincent J; Dong, Maxia; Anda, Robert F

2006-04-01

Alcohol is the most common and frequently used drug and has the potential to cause multiple deleterious effects throughout the lifespan. Because early age at initiation of alcohol use increases this potential and programs and laws are in place to attempt to delay the onset of alcohol use, we studied the relationship between multiple adverse childhood experiences (ACEs) and both the likelihood of ever drinking and the age at initiating alcohol use. This was a retrospective cohort study of 8417 adult health maintenance organization (HMO) members in California who completed a survey about ACEs, which included childhood abuse and neglect, growing up with various forms of household dysfunction and alcohol use in adolescence and adulthood. The main outcomes measured were ever drinking and age at initiating alcohol use among ever-drinkers for four age categories: < or = 14 years (early adolescence), 15 to 17 years (mid adolescence), and 18 to 20 years (late adolescence); age > or = 21 years was the referent. The relationship between the total number of adverse childhood experiences (ACE score) and early initiation of alcohol use (< or =14 years) among four birth cohorts dating back to 1900 was also examined. Eighty-nine percent of the cohort reported ever drinking; all individual ACEs except physical neglect increased the risk of ever using alcohol (p < .05). Among ever drinkers, initiating alcohol use by age 14 years was increased two- to threefold by individual ACEs (p < .05). ACEs also accounted for a 20% to 70% increased likelihood of alcohol use initiated during mid adolescence (15-17 years). The total number of ACEs (ACE score) had a very strong graded relationship to initiating alcohol use during early adolescence and a robust but somewhat less strong relationship to initiation during mid adolescence. For each of the four birth cohorts, the ACE score had a strong, graded relationship to initiating alcohol use by age 14 years (p < .05). Adverse childhood experiences are strongly related to ever drinking alcohol and to alcohol initiation in early and mid adolescence, and the ACE score had a graded or "dose-response" relationship to these alcohol use behaviors. The persistent graded relationship between the ACE score and initiation of alcohol use by age 14 for four successive birth cohorts dating back to 1900 suggests that the stressful effects of ACEs transcend secular changes, including the increased availability of alcohol, alcohol advertising, and the recent campaigns and health education programs to prevent alcohol use. These findings strongly suggest that efforts to delay the age of onset of drinking must recognize the contribution of multiple traumatic and stressful events to alcohol-seeking behavior among children and adolescents.

Hemispheric Asymmetries Depend on the Phonetic Feature: A Dichotic Study of Place of Articulation and Voicing in French Stops

ERIC Educational Resources Information Center

Bedoin, Nathalie; Ferragne, Emmanuel; Marsico, Egidio

2010-01-01

Dichotic listening experiments show a right-ear advantage (REA), reflecting a left-hemisphere (LH) dominance. However, we found a decrease in REA when the initial stop consonants of two simultaneous French CVC words differed in voicing rather than place of articulation (Experiment 1). This result suggests that the right hemisphere (RH) is more…

Molecular interactions of ROOTLESS CONCERNING CROWN AND SEMINAL ROOTS, a LOB domain protein regulating shoot-borne root initiation in maize (Zea mays L.)

PubMed Central

Majer, Christine; Xu, Changzheng; Berendzen, Kenneth W.; Hochholdinger, Frank

2012-01-01

Rootless concerning crown and seminal roots (Rtcs) encodes a LATERAL ORGAN BOUNDARIES domain (LBD) protein that regulates shoot-borne root initiation in maize (Zea mays L.). GREEN FLUORESCENT PROTEIN (GFP)-fusions revealed RTCS localization in the nucleus while its paralogue RTCS-LIKE (RTCL) was detected in the nucleus and cytoplasm probably owing to an amino acid exchange in a nuclear localization signal. Moreover, enzyme-linked immunosorbent assay (ELISA) experiments demonstrated that RTCS primarily binds to LBD DNA motifs. RTCS binding to an LBD motif in the promoter of the auxin response factor (ARF) ZmArf34 and reciprocally, reciprocal ZmARF34 binding to an auxin responsive element motif in the promoter of Rtcs was shown by electrophoretic mobility shift assay experiments. In addition, comparative qRT-PCR of wild-type versus rtcs coleoptilar nodes suggested RTCS-dependent activation of ZmArf34 expression. Consistently, luciferase reporter assays illustrated the capacity of RTCS, RTCL and ZmARF34 to activate downstream gene expression. Finally, RTCL homo- and RTCS/RTCL hetero-interaction were demonstrated in yeast-two-hybrid and bimolecular fluorescence complementation experiments, suggesting a role of these complexes in downstream gene regulation. In summary, the data provide novel insights into the molecular interactions resulting in crown root initiation in maize. PMID:22527397

Molecular interactions of ROOTLESS CONCERNING CROWN AND SEMINAL ROOTS, a LOB domain protein regulating shoot-borne root initiation in maize (Zea mays L.).

PubMed

Majer, Christine; Xu, Changzheng; Berendzen, Kenneth W; Hochholdinger, Frank

2012-06-05

Rootless concerning crown and seminal roots (Rtcs) encodes a LATERAL ORGAN BOUNDARIES domain (LBD) protein that regulates shoot-borne root initiation in maize (Zea mays L.). GREEN FLUORESCENT PROTEIN (GFP)-fusions revealed RTCS localization in the nucleus while its paralogue RTCS-LIKE (RTCL) was detected in the nucleus and cytoplasm probably owing to an amino acid exchange in a nuclear localization signal. Moreover, enzyme-linked immunosorbent assay (ELISA) experiments demonstrated that RTCS primarily binds to LBD DNA motifs. RTCS binding to an LBD motif in the promoter of the auxin response factor (ARF) ZmArf34 and reciprocally, reciprocal ZmARF34 binding to an auxin responsive element motif in the promoter of Rtcs was shown by electrophoretic mobility shift assay experiments. In addition, comparative qRT-PCR of wild-type versus rtcs coleoptilar nodes suggested RTCS-dependent activation of ZmArf34 expression. Consistently, luciferase reporter assays illustrated the capacity of RTCS, RTCL and ZmARF34 to activate downstream gene expression. Finally, RTCL homo- and RTCS/RTCL hetero-interaction were demonstrated in yeast-two-hybrid and bimolecular fluorescence complementation experiments, suggesting a role of these complexes in downstream gene regulation. In summary, the data provide novel insights into the molecular interactions resulting in crown root initiation in maize.

Initial Development of a Spatially Separated Speech-in-Noise and Localization Training Program

PubMed Central

Tyler, Richard S.; Witt, Shelley A.; Dunn, Camille C.; Wang, Wenjun

2010-01-01

Objective This article describes the initial development of a novel approach for training hearing-impaired listeners to improve their ability to understand speech in the presence of background noise and to also improve their ability to localize sounds. Design Most people with hearing loss, even those well fit with hearing devices, still experience significant problems understanding speech in noise. Prior research suggests that at least some subjects can experience improved speech understanding with training. However, all training systems that we are aware of have one basic, critical limitation. They do not provide spatial separation of the speech and noise, therefore ignoring the potential benefits of training binaural hearing. In this paper we describe our initial experience with a home-based training system that includes spatially separated speech-in-noise and localization training. Results Throughout the development of this system patient input, training and preliminary pilot data from individuals with bilateral cochlear implants were utilized. Positive feedback from subjective reports indicated that some individuals were engaged in the treatment, and formal testing showed benefit. Feedback and practical issues resulted from the reduction of an eight-loudspeaker to a two-loudspeaker system. Conclusions These preliminary findings suggest we have successfully developed a viable spatial hearing training system that can improve binaural hearing in noise and localization. Applications include, but are not limited to, hearing with hearing aids and cochlear implants. PMID:20701836

Fault geometry and mechanics of marly carbonate multilayers: An integrated field and laboratory study from the Northern Apennines, Italy

NASA Astrophysics Data System (ADS)

Giorgetti, C.; Collettini, C.; Scuderi, M. M.; Barchi, M. R.; Tesei, T.

2016-12-01

Sealing layers are often represented by sedimentary sequences characterized by alternating strong and weak lithologies. When involved in faulting processes, these mechanically heterogeneous multilayers develop complex fault geometries. Here we investigate fault initiation and evolution within a mechanical multilayer by integrating field observations and rock deformation experiments. Faults initiate with a staircase trajectory that partially reflects the mechanical properties of the involved lithologies, as suggested by our deformation experiments. However, some faults initiating at low angles in calcite-rich layers (θi = 5°-20°) and at high angles in clay-rich layers (θi = 45°-86°) indicate the important role of structural inheritance at the onset of faulting. With increasing displacement, faults develop well-organized fault cores characterized by a marly, foliated matrix embedding fragments of limestone. The angles of fault reactivation, which concentrate between 30° and 60°, are consistent with the low friction coefficient measured during our experiments on marls (μs = 0.39), indicating that clay minerals exert a main control on fault mechanics. Moreover, our integrated analysis suggests that fracturing and faulting are the main mechanisms allowing fluid circulation within the low-permeability multilayer, and that its sealing integrity can be compromised only by the activity of larger faults cutting across its entire thickness.

A Review of Empirical Analyses of Disinvestment Initiatives.

PubMed

Chambers, James D; Salem, Mark N; D'Cruz, Brittany N; Subedi, Prasun; Kamal-Bahl, Sachin J; Neumann, Peter J

Disinvesting in low-value health care services provides opportunities for investment in higher value care and thus an increase in health care efficiency. To identify international experience with disinvestment initiatives and to review empirical analyses of disinvestment initiatives. We performed a literature search using the PubMed database to identify international experience with disinvestment initiatives. We also reviewed empirical analyses of disinvestment initiatives. We identified 26 unique disinvestment initiatives implemented across 11 countries. Nineteen addressed multiple intervention types, six addressed only drugs, and one addressed only devices. We reviewed 18 empirical analyses of disinvestment initiatives: 7 reported that the initiative was successful, 8 reported that the initiative was unsuccessful, and 3 reported that findings were mixed; that is, the study considered multiple services and reported a decrease in the use of some but not others. Thirty-seven low-value services were evaluated across the 18 empirical analyses, for 14 (38%) of which the disinvestment initiative led to a decline in use. Six of the seven studies that reported the disinvestment initiative to be successful included an attempt to promote the disinvestment initiative among participating clinicians. The success of disinvestment initiatives has been mixed, with fewer than half the identified empirical studies reporting that use of the low-value service was reduced. Our findings suggest that promotion of the disinvestment initiative among clinicians is a key component to the success of the disinvestment initiative. Copyright © 2017 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.

Dating violence and girls in the juvenile justice system.

PubMed

Kelly, Patricia J; Cheng, An-Lin; Peralez-Dieckmann, Esther; Martinez, Elisabeth

2009-09-01

The purpose of this study is to explore the prevalence and associated behaviors of dating violence among a population of girls in the juvenile justice system. A sample of 590 girls from an urban juvenile justice system completed a questionnaire assessing attitudes and self-efficacy about and occurrence of dating violence. The analysis developed a random effect model to determine a risk profile for dating violence. The strongest predictors of dating violence were (a) initial sexual experience at age 13 or earlier, (b) unwillingness of initial sexual experience, (c) drug use, and (d) low self-efficacy about preventing dating violence. The high prevalence of dating violence and associated behaviors among participants suggests the importance of implementing primary prevention programs to assist preteen girls in delaying initial sexual intercourse and in learning techniques to prevent dating violence.

Bridging the Policy-Implementation Gap in Federal Health Systems: Lessons from the Nigerian Experience

PubMed Central

Sokpo, Emmanuel

2014-01-01

The Partnership for Reviving Routine Immunization in Northern Nigeria - Maternal, Newborn and Child Health initiative supports efforts by the government of Nigeria to bridge primary health care (PHC) policies and services at three levels of government: federal, state and local. The paper suggests that understandings informed by complexity theory and complex adaptive systems have been helpful in shaping policy and programme design across these levels. To illustrate this, three initiatives are explored: Bringing PHC under one roof, enhancing access to funding provided by the Global Alliance for Vaccines and Immunization, and strengthening the midwives service scheme. These initiatives have demonstrated how concepts and experience developed at subnational level can influence national policy and practice, and how work at subnational levels can add value to nationally conceived and nationally driven plans for PHC. PMID:28299131

Post-conditioning experience with acute or chronic inflammatory pain reduces contextual fear conditioning in the rat

PubMed Central

Johnston, Ian N.; Maier, Steven F.; Rudy, Jerry W.; Watkins, Linda R.

2017-01-01

There is evidence that pain can impact cognitive function in people. The present study evaluated whether Pavlovian fear conditioning in rats would be reduced if conditioning were followed by persistent inflammatory pain induced by a subcutaneous injection of dilute formalin or complete Freund's adjuvant (CFA) on the dorsal lumbar surface of the back. Formalin-induced pain specifically impaired contextual fear conditioning but not auditory cue conditioning (Experiment 1A). Moreover, formalin pain only impaired contextual fear conditioning if it was initiated within 1 h of conditioning and did not have a significant effect if initiated 2, 8 or 32 h after (Experiments 1A and 1B). Experiment 2 showed that formalin pain initiated after a session of context pre-exposure reduced the ability of that pre-exposure to facilitate contextual fear when the rat was limited to a brief exposure to the context during conditioning. Similar impairments in context- but not CS-fear conditioning were also observed if the rats received an immediate post-conditioning injection with CFA (Experiment 3). Finally, we confirmed that formalin and CFA injected s.c. on the back induced pain-indicative behaviours, hyperalgesia and allodynia with a similar timecourse to intraplantar injections (Experiment 4). These results suggest that persistent pain impairs learning in a hippocampus-dependent task, and may disrupt processes that encode experiences into long-term memory. PMID:21920390

Differential attentional responding in caesarean versus vaginally delivered infants.

PubMed

Adler, Scott A; Wong-Kee-You, Audrey M B

2015-11-01

Little is known about the role that the birth experience plays in brain and cognitive development. Recent research has suggested that birth experience influences the development of the somatosensory cortex, an area involved in spatial attention to sensory information. In this study, we explored whether differences in spatial attention would occur in infants who had different birth experiences, as occurs for caesarean versus vaginal delivery. Three-month-old infants performed either a spatial cueing task or a visual expectation task. We showed that caesarean-delivered infants' stimulus-driven, reflexive attention was slowed relative to vaginally delivered infants', whereas their cognitively driven, voluntary attention was unaffected. Thus, types of birth experience influence at least one form of infants' attention, and possibly any cognitive process that relies on spatial attention. This study also suggests that birth experience influences the initial state of brain functioning and, consequently, should be considered in our understanding of brain development.

Exceptionally good? Positive experiences of NHS care and treatment surprises lymphoma patients: a qualitative interview study.

PubMed

Ziebland, Sue; Evans, Julie; Toynbee, Polly

2011-03-01

Initial analysis of an interview study with patients about their experiences of lymphoma identified a strong emergent theme suggesting people were surprised to receive good care in the UK National Health Service. This qualitative analysis helps illuminate the disparity between public perceptions of NHS care and individual experiences. Forty-one women and men with lymphoma were interviewed at home by an academic social scientist; nine who had had all their treatment before 1997 were excluded from this analysis. Initial qualitative thematic analysis used constant comparison and axial coding. Using narrative analytic methods, we explored how the accounts of positive experiences were structured and framed as well as what was said. Every person we interviewed described positive experiences of the NHS. These included the skills and humanity of the specialist staff involved in their care, the team work, the organization of care and communication and information. However, these positive experiences were often framed as personal good fortune rather than an indication that a high standard might be expected of NHS cancer care. Participants' accounts also suggest a discrepancy through the use of framing devices that imply that less professional, kind and caring treatment might be expected. People may be able to maintain the apparently contradictory opinions that the NHS is not very good, even if their own experience of care is excellent, if they construct their own experience as 'lucky'. Health professionals could help by reassuring patients with a more positive, realistic expectation of specialist care. © 2010 The Authors. Health Expectations © 2010 Blackwell Publishing Ltd.

Exceptionally good? Positive experiences of NHS care and treatment surprises lymphoma patients: a qualitative interview study

PubMed Central

Ziebland, Sue; Evans, Julie; Toynbee, Polly

2010-01-01

Abstract Objective  Initial analysis of an interview study with patients about their experiences of lymphoma identified a strong emergent theme suggesting people were surprised to receive good care in the UK National Health Service. This qualitative analysis helps illuminate the disparity between public perceptions of NHS care and individual experiences. Participants and setting  Forty‐one women and men with lymphoma were interviewed at home by an academic social scientist; nine who had had all their treatment before 1997 were excluded from this analysis. Design  Initial qualitative thematic analysis used constant comparison and axial coding. Using narrative analytic methods, we explored how the accounts of positive experiences were structured and framed as well as what was said. Results  Every person we interviewed described positive experiences of the NHS. These included the skills and humanity of the specialist staff involved in their care, the team work, the organization of care and communication and information. However, these positive experiences were often framed as personal good fortune rather than an indication that a high standard might be expected of NHS cancer care. Participants’ accounts also suggest a discrepancy through the use of framing devices that imply that less professional, kind and caring treatment might be expected. Conclusion  People may be able to maintain the apparently contradictory opinions that the NHS is not very good, even if their own experience of care is excellent, if they construct their own experience as ‘lucky’. Health professionals could help by reassuring patients with a more positive, realistic expectation of specialist care. PMID:20579116

Phonological effects in handwriting production: evidence from the implicit priming paradigm.

PubMed

Afonso, Olivia; Álvarez, Carlos J

2011-11-01

In the present article, we report 3 experiments using the odd-man-out variant of the implicit priming paradigm, aimed at determining the role played by phonological information during the handwriting process. Participants were asked to write a small set of words learned in response to prompts. Within each block, response words could share initial segments (constant homogeneous) or not (heterogeneous). Also, 2 variable homogeneous blocks were created by including a response word that did not share orthographic onset with the other response (odd-man-out). This odd-man-out could be phonologically related to the targets or not. Experiment 1 showed a preparation effect in the constant homogeneous condition, which disappeared (spoil effect) in the variable condition not phonologically related. However, no spoil effect was found when the odd-man-out shared the phonological initial segment with the targets. In Experiment 2, we obtained a spoil effect in the variable phonologically related condition, but it was significantly smaller than in the variable not phonologically related condition. The effects observed in Experiment 2 vanished in Experiment 3 under articulatory suppression, suggesting that they originated at a sublexical level. These findings suggest that phonological sublexical information is used during handwriting and provide evidence that the implicit priming paradigm (and the odd-man-out version of this) is a suitable tool for handwriting production research.

Impact Initiation of Rods of Pressed Polytetrafluoroethylene (PTFE) and Aluminum Powders

NASA Astrophysics Data System (ADS)

Mock, Willis, Jr.

2005-07-01

A gas gun has been used to investigate the shock initiation of rods consisting of a mixture of 74 wt % PTFE (28 μm particle size) and 26 wt % aluminum (5 μm particle size) powders. The 7.6 mm diameter by 51 mm long rods were fabricated from material that had been pressed and sintered to a full density of 2.27 gm/cm^ 3. The rods were sabot-launched into 4340 steel anvils at impact velocities ranging from 104 to 777 m/s. This corresponds to calculated impact stresses of 3.3 to 48 kbar. The experiments were carried out in a 50-100 mtorr vacuum. A framing camera was used to observe the time sequence of events. These include changes in rod shape, fracture, and the initiation and evolution of the reaction phenomena. Observation of first visible light after impact was taken as the initiation time. Initiation of the reaction occurred at discrete locations in the rod material. At low velocity, no initiation occurred. Above an initiation threshold, the initiation time dropped abruptly from 56 μs just above threshold to 4 μs at the highest impact velocity. Two experiments were performed for pure PTFE material for comparison with the PTFE/Al rods. The pure PTFE showed more extensive radial flow without obvious brittle fracture. For the 784 m/s impact experiment, small points of light were observed on the edge of the mushroomed portion of the rod about 20 μs after impact, suggesting the onset of chemical reaction.

Neural Overlap in Item Representations Across Episodes Impairs Context Memory.

PubMed

Kim, Ghootae; Norman, Kenneth A; Turk-Browne, Nicholas B

2018-06-12

We frequently encounter the same item in different contexts, and when that happens, memories of earlier encounters can get reactivated. We examined how existing memories are changed as a result of such reactivation. We hypothesized that when an item's initial and subsequent neural representations overlap, this allows the initial item to become associated with novel contextual information, interfering with later retrieval of the initial context. Specifically, we predicted a negative relationship between representational similarity across repeated experiences of an item and subsequent source memory for the initial context. We tested this hypothesis in an fMRI study, in which objects were presented multiple times during different tasks. We measured the similarity of the neural patterns in lateral occipital cortex that were elicited by the first and second presentations of objects, and related this neural overlap score to subsequent source memory. Consistent with our hypothesis, greater item-specific pattern similarity was linked to worse source memory for the initial task. In contrast, greater reactivation of the initial context was associated with better source memory. Our findings suggest that the influence of novel experiences on an existing context memory depends on how reliably a shared component (i.e., item) is represented across these episodes.

A Feasibility Experiment for a Soft X-Ray Laser

DTIC Science & Technology

1976-09-01

has embarked on a large scale laser fusion program initially aimed at achieving sufficient thermometric yield from a single pellet to initiate a...gold, aluminum ). The report suggests that 10 to 20 percent of the incident laser energy can be converted to X rays below 1 keV. A Lawrence Livermore...Computa- tions of the population inversion for the inner shell electrons, as found in 3 I-.--I~ . . AFWL-TR-76-107 aluminum , indicate a favorable

Building organizational capacity for evidence use: the experience of two Canadian healthcare organizations.

PubMed

Humphries, Serena; Hampe, Tanis; Larsen, Derrick; Bowen, Sarah

2013-01-01

The use of evidence to inform decisions at the program level within healthcare organizations is a priority. The purpose of this article is to provide an overview of an innovative collaboration between two Canadian healthcare organizations to build organizational capacity for evidence use in program planning, implementation, and evaluation. The lessons learned from the initiative suggest that other healthcare organizations would find the capacity-building strategies identified and developed through the initiative useful.

Style preference survey: a report on the psychometric properties and a cross-validation experiment.

PubMed

Smith, Sherri L; Ricketts, Todd; McArdle, Rachel A; Chisolm, Theresa H; Alexander, Genevieve; Bratt, Gene

2013-02-01

Several self-report measures exist that target different aspects of outcomes for hearing aid use. Currently, no comprehensive questionnaire specifically assesses factors that may be important for differentiating outcomes pertaining to hearing aid style. The goal of this work was to develop the Style Preference Survey (SPS), a questionnaire aimed at outcomes associated with hearing aid style differences. Two experiments were conducted. After initial item development, Experiment 1 was conducted to refine the items and to determine its psychometric properties. Experiment 2 was designed to cross-validate the findings from the initial experiment. An observational design was used in both experiments. Participants who wore traditional, custom-fitted (TC) or open-canal (OC) style hearing aids from 3 mo to 3 yr completed the initial experiment. One-hundred and eighty-four binaural hearing aid users (120 of whom wore TC hearing aids and 64 of whom wore OC hearing aids) participated. A new sample of TC and OC users (n = 185) participated in the cross-validation experiment. Currently available self-report measures were reviewed to identify items that might differentiate between hearing aid styles, particularly preference for OC versus TC hearing aid styles. A total of 15 items were selected and modified from available self-report measures. An additional 55 items were developed through consensus of six audiologists for the initial version of the SPS. In the first experiment, the initial SPS version was mailed to 550 veterans who met the inclusion criteria. A total of 184 completed the SPS. Approximately three weeks later, a subset of participants (n = 83) completed the SPS a second time. Basic analyses were conducted to evaluate the psychometric properties of the SPS including subscale structure, internal consistency, test-retest reliability, and responsiveness. Based on the results of Experiment 1, the SPS was revised. A cross-validation experiment was then conducted using the revised version of the SPS to confirm the subscale structure, internal consistency, and responsiveness of the questionnaire in a new sample of participants. The final factor analysis led to the ultimate version of the SPS, which had a total of 35 items encompassing five subscales: (1) Feedback, (2) Occlusion/Own Voice Effects, (3) Localization, (4) Fit, Comfort, and Cosmetics, and (5) Ease of Use. The internal consistency of the total SPS (Cronbach's α = .92) and of the subscales (each Cronbach's α > .75) was high. Intraclass correlations (ICCs) showed that the test-retest reliability of the total SPS (ICC = .93) and of the subscales (each ICC > .80) also was high. TC hearing aid users had significantly poorer outcomes than OC hearing aid users on 4 of the 5 subscales, suggesting that the SPS largely is responsive to factors related to style-specific differences. The results suggest that the SPS has good psychometric properties and is a valid and reliable measure of outcomes related to style-specific, hearing aid preference. American Academy of Audiology.

FIESTA; Minority Television Programming.

ERIC Educational Resources Information Center

Marshall, Wes; And Others

The suggestions for planning, running, and evaluating minority television programing presented in this handbook are based on the experience and example of the FIESTA project (Tucson, Arizona). After initiating the reader into the topic of minority programing, the document disucsses the following topics: broadcast research, origins of the FIESTA…

Experience-Seeking Characteristics of Methadone Clients.

ERIC Educational Resources Information Center

Kohn, Paul M.; And Others

1979-01-01

Methadone clients scored higher than controls on measures reflecting boredom, desire for change and attraction to physically thrilling activities. Correlations of these measures with length of most recent dependency before treatment, time on program, and time since initial dependency suggest peculiarities of methadone clients antedated involvement…

[Self-judgment of personality traits and cognitive dimensions of the self].

PubMed

Horiuchi, T

1996-12-01

When people make a judgment as to whether a trait describes themselves or not, cognitive structure about the self must play an important role. Cognitive dimensions are a characteristic of such cognitive structure. The present study examined whether a self-referent information processing was mediated by cognitive dimensions of the self. For the purpose, Klein, Loftus, and Burton's task facilitation paradigm (1989) was adapted, which consisted of performing in succession two tasks, initial and target, for each trait adjective used. Experiment 1, which examined the evaluative dimension, showed that an evaluative processing in the target task was facilitated when the initial task was self-referent. Experiment 2, which examined six dimensions, showed that processing of the relevant dimension in the target task was facilitated when the initial task was self-referent. These results suggest that a self-referent information processing is mediated by cognitive dimensions of the self.

Shock experiments on maskelynite-bearing anorthosite

NASA Technical Reports Server (NTRS)

Lambert, P.; Grieve, R. A. F.

1984-01-01

A series of shock recovery experiments over 9.9-60.4 GPa have been carried out on naturally shocked anorthosite from the Mistastin impact structure in Labrador consisting primarily of diaplectic plagioclase glass or maskelynite, An(50), and pyroxene. Petrographic observations of the experimental products indicate that the component minerals and diaplectic glasses generally retained their initial character throughout, the only exception being the increase in fracturing which occurred in the 9.9 GPa shot. Reshocking at pressures higher than the initial shock tends to lower the refractive index of maskelynite. The increase in refractive index of maskelynite reshocked to pressures lower than the initial pressure is interpreted as due to shock densification of the diaplectic glass above the Hugoniot elastic limit and below the mixed phase regime. The data suggest that the low-high-low density transition of maskelynite occurs about 8 GPa below that of the crystal of corresponding composition.

Will sea ice thickness initialisation improve Arctic seasonal-to-interannual forecast skill?

NASA Astrophysics Data System (ADS)

Day, J. J.; Hawkins, E.; Tietsche, S.

2014-12-01

A number of recent studies have suggested that Arctic sea ice thickness is an important predictor of Arctic sea ice extent. However, coupled forecast systems do not currently use sea ice thickness observations in their initialization and are therefore missing a potentially important source of additional skill. A set of ensemble potential predictability experiments, with a global climate model, initialized with and without knowledge of the sea ice thickness initial state, have been run to investigate this. These experiments show that accurate knowledge of the sea ice thickness field is crucially important for sea ice concentration and extent forecasts up to eight months ahead. Perturbing sea ice thickness also has a significant impact on the forecast error in the 2m temperature and surface pressure fields a few months ahead. These results show that advancing capabilities to observe and assimilate sea ice thickness into coupled forecast systems could significantly increase skill.

Temporal framing and the hidden-zero effect: rate-dependent outcomes on delay discounting.

PubMed

Naudé, Gideon P; Kaplan, Brent A; Reed, Derek D; Henley, Amy J; DiGennaro Reed, Florence D

2018-05-01

Recent research suggests that presenting time intervals as units (e.g., days) or as specific dates, can modulate the degree to which humans discount delayed outcomes. Another framing effect involves explicitly stating that choosing a smaller-sooner reward is mutually exclusive to receiving a larger-later reward, thus presenting choices as an extended sequence. In Experiment 1, participants (N = 201) recruited from Amazon Mechanical Turk completed the Monetary Choice Questionnaire in a 2 (delay framing) by 2 (zero framing) design. Regression suggested a main effect of delay, but not zero, framing after accounting for other demographic variables and manipulations. We observed a rate-dependent effect for the date-framing group, such that those with initially steep discounting exhibited greater sensitivity to the manipulation than those with initially shallow discounting. Subsequent analyses suggest these effects cannot be explained by regression to the mean. Experiment 2 addressed the possibility that the null effect of zero framing was due to within-subject exposure to the hidden- and explicit-zero conditions. A new Amazon Mechanical Turk sample completed the Monetary Choice Questionnaire in either hidden- or explicit-zero formats. Analyses revealed a main effect of reward magnitude, but not zero framing, suggesting potential limitations to the generality of the hidden-zero effect. © 2018 Society for the Experimental Analysis of Behavior.

The Edge Factor in Early Word Segmentation: Utterance-Level Prosody Enables Word Form Extraction by 6-Month-Olds

PubMed Central

Johnson, Elizabeth K.; Seidl, Amanda; Tyler, Michael D.

2014-01-01

Past research has shown that English learners begin segmenting words from speech by 7.5 months of age. However, more recent research has begun to show that, in some situations, infants may exhibit rudimentary segmentation capabilities at an earlier age. Here, we report on four perceptual experiments and a corpus analysis further investigating the initial emergence of segmentation capabilities. In Experiments 1 and 2, 6-month-olds were familiarized with passages containing target words located either utterance medially or at utterance edges. Only those infants familiarized with passages containing target words aligned with utterance edges exhibited evidence of segmentation. In Experiments 3 and 4, 6-month-olds recognized familiarized words when they were presented in a new acoustically distinct voice (male rather than female), but not when they were presented in a phonologically altered manner (missing the initial segment). Finally, we report corpus analyses examining how often different word types occur at utterance boundaries in different registers. Our findings suggest that edge-aligned words likely play a key role in infants’ early segmentation attempts, and also converge with recent reports suggesting that 6-month-olds’ have already started building a rudimentary lexicon. PMID:24421892

Chancellor Water Colloids: Characterization and Radionuclide Associated Transport

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

Reimus, Paul William; Boukhalfa, Hakim

2014-09-26

Column transport experiments were conducted in which water from the Chancellor nuclear test cavity was transported through crushed volcanic tuff from Pahute Mesa. In one experiment, the cavity water was spiked with solute 137Cs, and in another it was spiked with 239/240Pu(IV) nanocolloids. A third column experiment was conducted with no radionuclide spike at all, although the 137Cs concentrations in the water were still high enough to quantify in the column effluent. The radionuclides strongly partitioned to natural colloids present in the water, which were characterized for size distribution, mass concentration, zeta potential/surface charge, critical coagulation concentration, and qualitative mineralogy.more » In the spiked water experiments, the unanalyzed portion of the high-concentration column effluent samples were combined and re-injected into the respective columns as a second pulse. This procedure was repeated again for a third injection. Measurable filtration of the colloids was observed after each initial injection of the Chancellor water into the columns, but the subsequent injections (spiked water experiments only) exhibited no apparent filtration, suggesting that the colloids that remained mobile after relatively short transport distances were more resistant to filtration than the initial population of colloids. It was also observed that while significant desorption of 137Cs from the colloids occurred after the first injection in both the spiked and unspiked waters, subsequent injections of the spiked water exhibited much less 137Cs desorption (much greater 137Cs colloid-associated transport). This result suggests that the 137Cs that remained associated with colloids during the first injection represented a fraction that was more strongly adsorbed to the mobile colloids than the initial 137Cs associated with the colloids. A greater amount of the 239/240Pu desorbed from the colloids during the second column injection compared to the first injection, but then desorption decreased significantly in the third injection. This result suggests that the Pu(IV) nanocolloids probably at least partially dissolved during and after the first injection, resulting in enhanced desorption from the colloids during the second injection, but by the third injection the Pu started following the same trend that was observed for 137Cs. The experiments suggest a transport scale dependence in which mobile colloids and colloid-associated radionuclides observed at downstream points along a flow path have a greater tendency to remain mobile along the flow path than colloids and radionuclides observed at upstream points. This type of scale dependence may help explain observations of colloid-facilitated Pu transport over distances of up to 2 km at Pahute Mesa.« less

When two eyes are better than one in prehension: monocular viewing and end-point variance.

PubMed

Loftus, Andrea; Servos, Philip; Goodale, Melvyn A; Mendarozqueta, Nicole; Mon-Williams, Mark

2004-10-01

Previous research has suggested that binocular vision plays an important role in prehension. It has been shown that removing binocular vision affects (negatively) both the planning and on-line control of prehension. It has been suggested that the adverse impact of removing binocular vision is because monocular viewing results in an underestimation of target distance in visuomotor tasks. This suggestion is based on the observation that the kinematics of prehension are altered when viewing monocularly. We argue that it is not possible to draw unambiguous conclusions regarding the accuracy of distance perception from these data. In experiment 1, we found data that contradict the idea that a consistent visuomotor underestimation of target distance is an inevitable consequence of monocular viewing. Our data did show, however, that positional variance increases under monocular viewing. We provide an alternative explanation for the kinematic changes found when binocular vision is removed. Our account is based on the changes in movement kinematics that occur when end-point variance is altered following the removal of binocular vision. We suggest that the removal of binocular vision leads to greater perceptual uncertainty (e.g. less precise stimulus cues), resulting in changes in the kinematics of the movement (longer duration movements). Our alternative account reconciles some differences within the research literature. We conducted a series of experiments to explore further the issue of when binocular information is advantageous in prehension. Three subsequent experiments were employed which varied binocular/monocular viewing in selectively lit conditions. Experiment 2 explored the differences in prehension measured between monocular and binocular viewing in a full cue environment with a continuous view of the target object. Experiment 3 required participants to reach, under a monocular or binocular view, for a continuously visible self-illuminated target object in an otherwise dark room. In Experiment 3, the participant could neither see the target object nor the reaching hand following initiation of the prehension movement. Our results suggest that binocular vision contributes to prehension by providing additional information (cues) to the nervous system. These cues appear to be weighted differentially according to the particular constellation of stimulus cues available to the participants when reaching to grasp. One constant advantage of a binocular view appears to be the provision of on-line information regarding the position of the hand relative to the target. In reduced cue conditions (i.e. where a view of the target object is lost following initiation of the movement), binocular information regarding target location appears to be particularly useful in the initial programming of reach distance. Our results are a step towards establishing the specific contributions that binocular vision makes to the control of prehension.

Potential role of salinity in ENSO and MJO predictions

NASA Astrophysics Data System (ADS)

Zhu, J.; Kumar, A.; Murtugudde, R. G.; Xie, P.

2017-12-01

Studies have suggested that ocean salinity can vary in response to ENSO and MJO. For example, during an El Niño event, sea surface salinity decreases in the western and central equatorial Pacific, as a result of zonal advection of low salinity water by anomalous eastward surface currents, and to a lesser extent as a result of a rainfall excess associated with atmospheric convection and warm water displacements. However, the effect of salinity on ENSO and MJO evolutions and their forecasts has been less explored. In this analysis, we explored the potential role of salinity in ENSO and MJO predictions by conducting sensitivity experiments with NCEP CFSv2. Firstly, two forecasts experiments are conducted to explore its effect on ENSO predictions, in which the interannual variability of salinity in the ocean initial states is either included or excluded. Comparisons suggested that the salinity variability is essential to correctly forecast the 2007/08 La Niña starting from April 2007. With realistic salinity initial states, the tendency to decay of the subsurface cold condition during the spring and early summer 2007 was interrupted by positive salinity anomalies in the upper central Pacific, which working together with the Bjerknes positive feedback, contributed to the development of the La Niña event. Our study suggests that ENSO forecasts will benefit from more accurate sustained salinity observations having large-scale spatial coverage. We also assessed the potential role of salinity in MJO by evaluating a long coupled free run that has a relatively realistic MJO simulation and a set of predictability experiment, both based on CFSv2. Diagnostics of the free run suggest that, while the intraseasonal SST variations lead convections by a quarter cycle, they are almost in phase only with changes in barrier layer thickness, thereby suggesting an active role of salinity on SST. Its effect on MJO predictions is further explored by controlling the surface salinity feedback during the predictability experiments.

Initial cash/asset ratio and asset prices: an experimental study.

PubMed

Caginalp, G; Porter, D; Smith, V

1998-01-20

A series of experiments, in which nine participants trade an asset over 15 periods, test the hypothesis that an initial imbalance of asset/cash will influence the trading price over an extended time. Participants know at the outset that the asset or "stock" pays a single dividend with fixed expectation value at the end of the 15th period. In experiments with a greater total value of cash at the start, the mean prices during the trading periods are higher, compared with those with greater amount of asset, with a high degree of statistical significance. The difference is most significant at the outset and gradually tapers near the end of the experiment. The results are very surprising from a rational expectations and classical game theory perspective, because the possession of a large amount of cash does not lead to a simple motivation for a trader to bid excessively on a financial instrument. The gradual erosion of the difference toward the end of trading, however, suggests that fundamental value is approached belatedly, offering some consolation to the rational expectations theory. It also suggests that there is a time scale on which an evolution toward fundamental value occurs. The experimental results are qualitatively compatible with the price dynamics predicted by a system of differential equations based on asset flow. The results have broad implications for the marketing of securities, particularly initial and secondary public offerings, government bonds, etc., where excess supply has been conjectured to suppress prices.

Initial cash/asset ratio and asset prices: An experimental study

PubMed Central

Caginalp, Gunduz; Porter, David; Smith, Vernon

1998-01-01

A series of experiments, in which nine participants trade an asset over 15 periods, test the hypothesis that an initial imbalance of asset/cash will influence the trading price over an extended time. Participants know at the outset that the asset or “stock” pays a single dividend with fixed expectation value at the end of the 15th period. In experiments with a greater total value of cash at the start, the mean prices during the trading periods are higher, compared with those with greater amount of asset, with a high degree of statistical significance. The difference is most significant at the outset and gradually tapers near the end of the experiment. The results are very surprising from a rational expectations and classical game theory perspective, because the possession of a large amount of cash does not lead to a simple motivation for a trader to bid excessively on a financial instrument. The gradual erosion of the difference toward the end of trading, however, suggests that fundamental value is approached belatedly, offering some consolation to the rational expectations theory. It also suggests that there is a time scale on which an evolution toward fundamental value occurs. The experimental results are qualitatively compatible with the price dynamics predicted by a system of differential equations based on asset flow. The results have broad implications for the marketing of securities, particularly initial and secondary public offerings, government bonds, etc., where excess supply has been conjectured to suppress prices. PMID:11038619

Iron, Manganese and Copper Release from Synthetic Hydroxyapatite

NASA Technical Reports Server (NTRS)

Sutter, B.; Hossner, L. R.; Ming, Douglas W.

1999-01-01

Kinetic stir-flow dissolution experiments were performed on iron- (Fe-SHA), manganese- (Mn-SHA), and copper- (Cu-SHA) containing synthetic hydroxyapatites. Solution treatments consisted of de-ionized water, citric acid and DTPA. Initially, Mn concentrations were higher than Cu concentrations and Fe concentrations were the lowest in all treatments. At later times Mn and Cu concentrations dropped in the DTPA treatment while Fe rose to the concentration similar to Mn and Cu. At all times, metal release concentrations in the water and citric acid treatments followed the trend of Mn>Cu>Fe. Rietveld analysis of x-ray diffraction data and ^31P NMR indicated that the metals substituted for Ca in the SHA structure. However, EPR data suggested that a metal (hydr)oxide phase existed either on the SHA surface or between the SHA crystallites. The metal concentration trend of Mn>Cu>Fe suggested that the initial solution metal concentrations are dependent on the dissolution of (hydr)oxides from SHA surfaces or between SHA crystallites. Similar metal concentrations at later times in the DTPA experiments suggests that metal concentrations were controlled by the release of Mn, Cu, or Fe from the SHA structure.

Competition and Curriculum Diversity in Local Schooling Markets: Theory and Evidence.

ERIC Educational Resources Information Center

Adnett, Nick; Davies, Peter

2000-01-01

Based on conventional economic analysis, increasing competitive pressures on schools should promote greater curricular innovation and diversity. The United Kingdom's experience suggests that market-based reforms can initially create pressures to increase curriculum conformity in local schooling markets. Innovation incentives are greatest for…

Coherent Raman Studies of Shocked Liquids

NASA Astrophysics Data System (ADS)

McGrane, Shawn; Brown, Kathryn; Dang, Nhan; Bolme, Cynthia; Moore, David

2013-06-01

Transient vibrational spectroscopies offer the potential to directly observe time dependent shock induced chemical reaction kinetics. We report recent experiments that couple a hybrid picosecond/femtosecond coherent anti-Stokes Raman spectroscopy (CARS) diagnostic with our tabletop ultrafast laser driven shock platform. Initial results on liquids shocked to 20 GPa suggest that sub-picosecond dephasing at high pressure and temperature may limit the application of this nonresonant background free version of CARS. Initial results using interferometric CARS to increase sensitivity and overcome these limitations will be presented.

Applicability of initial optimal maternal and fetal electrocardiogram combination vectors to subsequent recordings

NASA Astrophysics Data System (ADS)

Yan, Hua-Wen; Huang, Xiao-Lin; Zhao, Ying; Si, Jun-Feng; Liu, Tie-Bing; Liu, Hong-Xing

2014-11-01

A series of experiments are conducted to confirm whether the vectors calculated for an early section of a continuous non-invasive fetal electrocardiogram (fECG) recording can be directly applied to subsequent sections in order to reduce the computation required for real-time monitoring. Our results suggest that it is generally feasible to apply the initial optimal maternal and fetal ECG combination vectors to extract the fECG and maternal ECG in subsequent recorded sections.

Stop identity cue as a cue to language identity

NASA Astrophysics Data System (ADS)

Castonguay, Paula Lisa

The purpose of the present study was to determine whether language membership could potentially be cued by the acoustic-phonetic detail of word-initial stops and retained all the way through the process of lexical access to aid in language identification. Of particular interest were language-specific differences in CE and CF word-initial stops. Experiment 1 consisted of an interlingual homophone production task. The purpose of this study was to examine how word-initial stop consonants differ in terms of acoustic properties in Canadian English (CE) and Canadian French (CF) interlingual homophones. The analyses from the bilingual speakers in Experiment 1 indicate that bilinguals do produce language-specific differences in CE and CF word-initial stops, and that closure duration, voice onset time, and burst spectral SD may provide cues to language identity in CE and CF stops. Experiment 2 consisted of a Phoneme and Language Categorization task. The purpose of this study was to examine how stop identity cues, such as VOT and closure duration, influence a listener to identify word-initial stop consonants as belonging to Canadian English (CE) or Canadian French (CF). The RTs from the bilingual listeners in this study indicate that bilinguals do perceive language-specific differences in CE and CF word-initial stops, and that voice onset time may provide cues to phoneme and language membership in CE and CF stops. Experiment 3 consisted of a Phonological-Semantic priming task. The purpose of this study was to examine how subphonetic variations, such as changes in the VOT, affect lexical access. The results of Experiment 3 suggest that language-specific cues, such as VOT, affects the composition of the bilingual cohort and that the extent to which English and/or French words are activated is dependent on the language-specific cues present in a word. The findings of this study enhanced our theoretical understanding of lexical structure and lexical access in bilingual speakers. In addition, this study provides further insight on cross-language effects at the subphonetic level.

Topology-optimized metasurfaces: impact of initial geometric layout.

PubMed

Yang, Jianji; Fan, Jonathan A

2017-08-15

Topology optimization is a powerful iterative inverse design technique in metasurface engineering and can transform an initial layout into a high-performance device. With this method, devices are optimized within a local design phase space, making the identification of suitable initial geometries essential. In this Letter, we examine the impact of initial geometric layout on the performance of large-angle (75 deg) topology-optimized metagrating deflectors. We find that when conventional metasurface designs based on dielectric nanoposts are used as initial layouts for topology optimization, the final devices have efficiencies around 65%. In contrast, when random initial layouts are used, the final devices have ultra-high efficiencies that can reach 94%. Our numerical experiments suggest that device topologies based on conventional metasurface designs may not be suitable to produce ultra-high-efficiency, large-angle metasurfaces. Rather, initial geometric layouts with non-trivial topologies and shapes are required.

Exaggerated response to mild stress in rats fed high-fat diet.

PubMed

Legendre, Ariadne; Harris, Ruth B S

2006-11-01

It has been suggested that high-fat (HF) diet exaggerates the stress-induced release of glucocorticoids due to activation of the hypothalamic-pituitary-adrenal (HPA) axis. In an initial experiment, in which rats were fed HF diet for 4 days, we found that HF-fed controls stopped gaining weight, indicating that they were hyperresponsive to the mild stress of tail bleeding but responded the same as low-fat (LF)-fed rats to the more severe stress of restraint. A second experiment confirmed these results when rats fed a HF diet for 4 days showed an exaggerated corticosterone release in response to an intraperitoneal injection of saline and movement to a novel cage, compared with LF-fed rats. Experiment 3 tested the same parameters as experiment 2 but interchanged the diets. This allowed us to differentiate between the effects of the dietary fat and the novelty of the diet. Additionally, this experiment determined whether hyperresponsiveness to mild stress in HF-fed rats was sustained during a prolonged exposure to diet. The results confirmed that a HF diet, not novelty, exaggerated the endocrine stress response after 9 days on the diet but that the effect was no longer present after 23 days on the diet. The hyperresponsiveness of the HPA axis in HF-fed rats is similar to that observed in animals that have been exposed to a significant chronic or acute stress, suggesting that the HF diet may initially be perceived as a stressor.

Early Adolescent Sexual Initiation as a Problem Behavior: A Comparative Study of Five Nations

PubMed Central

Madkour, Aubrey Spriggs; Farhat, Tilda; Halpern, Carolyn Tucker; Godeau, Emmanuelle; Gabhainn, Saoirse Nic

2010-01-01

Purpose Using a Problem Behavior Theory (PBT) framework, this paper examines the extent to which psychosocial correlates of early sexual initiation (before age 16) vary across developed nations. Methods Fifteen-year-old participants (n=5,624) in the 1997-1998 WHO collaborative Health Behavior in School-Aged Children survey (Finland, Scotland, France and Poland) and the 1996 US Add Health survey self-reported substance use (alcohol and tobacco), school attachment, positive parental communication, and early sexual intercourse experience. Stratifying by gender, we performed univariate, bivariate, and multivariable analyses controlling for family socioeconomic status, family structure, and nation fixed effects. Results Self-reported early sexual experience, substance use, school attachment and positive communication with parents varied significantly across nations for both boys and girls. In both crude and adjusted analyses, substance use was positively associated with early sexual experience among boys and girls across nations, although associations were stronger in Europe than the US (adjusted odds ratio [AOR] range 1.56-3.74). School attachment was similarly inversely related to early sexual experience among boys and girls across nations (AOR range 0.63-0.94). However, positive parent communication was significantly inversely related to early sexual experience only among US females (AOR 0.50). Conclusions Findings overall supported the fit of early adolescent sexual initiation as a risk behavior within a PBT framework cross-nationally, suggesting that similar factors could be targeted to prevent early sexual initiation across some developed nations. However further research is warranted examining the temporality of these relationships. PMID:20864009

Flower choice by naïve young crab spiders and the effect of subsequent experience.

PubMed

Morse

2000-05-01

Initial responses of naïve individuals to critical environmental stimuli provide important information about the innate contribution to behaviour, and subsequent responses to the same stimuli may show the role of experience in mediating those initial responses. To test the role of these factors, I measured initial patch choices and giving-up responses of just-emerged, naïve, second-instar crab spiders, Misumena vatia, on several hunting sites they encountered after leaving their natal nests. In follow-up tests I measured the effects of these experiences on subsequent patch choice decisions. The choice of hunting sites is a vital decision at all stages of the life cycle for sit-and-wait predators such as Misumena. In their initial tests these spiderlings remained more frequently on goldenrod (Solidago spp.) flowers than on green or yellow goldenrod buds, a preference they retained through tests run on 5 consecutive days. Individuals on green and yellow buds shifted sites more quickly and frequently than those from flowers, and made most of these moves to flowers, which attracted many more prey than did buds. These differences were not affected by age, energetic condition, or loss of information over the period of the experiment. Once spiderlings moved from buds, they showed a high, increasing tendency to move from buds in subsequent runs, those from flowers showed a consistently low tendency. These results suggest that spiderlings retain their innate behavioural patterns through the second instar, but that experience also plays a modest role in patch choice at this stage. Copyright 2000 The Association for the Study of Animal Behaviour.

Learning from Feedback: Spacing and the Delay-Retention Effect

ERIC Educational Resources Information Center

Smith, Troy A.; Kimball, Daniel R.

2010-01-01

Most modern research on the effects of feedback during learning has assumed that feedback is an error correction mechanism. Recent studies of feedback-timing effects have suggested that feedback might also strengthen initially correct responses. In an experiment involving cued recall of trivia facts, we directly tested several theories of…

The Effects of Membership-Group Similarity on Counseling Process and Outcome.

ERIC Educational Resources Information Center

Richards-Govere, Kimberly A. M.

Recent studies suggest that membership-group similarity may be a strong motivator in initiating a counseling relationship, but that similarities in attitudes, experiences, and cognition affect the counseling process and outcome. In addition, within group differences between members of the same ethnic group affect the counseling process and…

Bring Your Own Device: Parental Guidance (PG) Suggested

ERIC Educational Resources Information Center

Kiger, Derick; Herro, Dani

2015-01-01

Educators are incorporating students' mobile devices into the schooling experience via Bring Your Own Device (BYOD) initiatives. This is advantageous for many reasons, most notably, improving access to Internet resources and digital tools in support of teaching and learning. Obtaining parental support is key to BYOD success. Therefore, this study…

Phonological Planning during Sentence Production: Beyond the Verb.

PubMed

Schnur, Tatiana T

2011-01-01

The current study addresses the extent of phonological planning during spontaneous sentence production. Previous work shows that at articulation, phonological encoding occurs for entire phrases, but encoding beyond the initial phrase may be due to the syntactic relevance of the verb in planning the utterance. I conducted three experiments to investigate whether phonological planning crosses multiple grammatical phrase boundaries (as defined by the number of lexical heads of phrase) within a single phonological phrase. Using the picture-word interference paradigm, I found in two separate experiments a significant phonological facilitation effect to both the verb and noun of sentences like "He opens the gate." I also altered the frequency of the direct object and found longer utterance initiation times for sentences ending with a low-frequency vs. high-frequency object offering further support that the direct object was phonologically encoded at the time of utterance initiation. That phonological information for post-verbal elements was activated suggests that the grammatical importance of the verb does not restrict the extent of phonological planning. These results suggest that the phonological phrase is unit of planning, where all elements within a phonological phrase are encoded before articulation. Thus, consistent with other action sequencing behavior, there is significant phonological planning ahead in sentence production.

Timing of first sex before marriage and its correlates: evidence from India.

PubMed

Santhya, K G; Acharya, Rajib; Jejeebhoy, Shireen J; Ram, Usha

2011-03-01

While several studies have documented the extent of pre-marital sexual experience among young people in India, little work has been done to explore the factors that are correlated with the timing of pre-marital sexual initiation. This paper examines age at initiation of pre-marital sex, circumstances in which first sex was experienced, nature of first sexual experience and correlates of age at initiation of pre-marital sex. Life table estimates suggest that pre-marital sexual initiation occurred in adolescence for 1 in 20 young women and 1 in 10 young men. For the majority of these young people, their first sex was with an opposite-sex romantic partner. First sex, moreover, was unprotected for the majority and forced for sizeable proportion of young women. A number of individual, family-, peer- and community-level factors were correlated with age at first pre-marital sex. Moreover, considerable gender differences were apparent in the correlates of age at first pre-marital sex, with peer- and parent-level factors found more often to be significant for young women than men.

Rupture preparation process controlled by surface roughness on meter-scale laboratory fault

NASA Astrophysics Data System (ADS)

Yamashita, Futoshi; Fukuyama, Eiichi; Xu, Shiqing; Mizoguchi, Kazuo; Kawakata, Hironori; Takizawa, Shigeru

2018-05-01

We investigate the effect of fault surface roughness on rupture preparation characteristics using meter-scale metagabbro specimens. We repeatedly conducted the experiments with the same pair of rock specimens to make the fault surface rough. We obtained three experimental results under the same experimental conditions (6.7 MPa of normal stress and 0.01 mm/s of loading rate) but at different roughness conditions (smooth, moderately roughened, and heavily roughened). During each experiment, we observed many stick-slip events preceded by precursory slow slip. We investigated when and where slow slip initiated by using the strain gauge data processed by the Kalman filter algorithm. The observed rupture preparation processes on the smooth fault (i.e. the first experiment among the three) showed high repeatability of the spatiotemporal distributions of slow slip initiation. Local stress measurements revealed that slow slip initiated around the region where the ratio of shear to normal stress (τ/σ) was the highest as expected from finite element method (FEM) modeling. However, the exact location of slow slip initiation was where τ/σ became locally minimum, probably due to the frictional heterogeneity. In the experiment on the moderately roughened fault, some irregular events were observed, though the basic characteristics of other regular events were similar to those on the smooth fault. Local stress data revealed that the spatiotemporal characteristics of slow slip initiation and the resulting τ/σ drop for irregular events were different from those for regular ones even under similar stress conditions. On the heavily roughened fault, the location of slow slip initiation was not consistent with τ/σ anymore because of the highly heterogeneous static friction on the fault, which also decreased the repeatability of spatiotemporal distributions of slow slip initiation. These results suggest that fault surface roughness strongly controls the rupture preparation process, and generally increases its complexity with the degree of roughness.

Expression patterns of TEL genes in Poaceae suggest a conserved association with cell differentiation.

PubMed

Paquet, Nicolas; Bernadet, Marie; Morin, Halima; Traas, Jan; Dron, Michel; Charon, Celine

2005-06-01

Poaceae species present a conserved distichous phyllotaxy (leaf position along the stem) and share common properties with respect to leaf initiation. The goal of this work was to determine if these common traits imply common genes. Therefore, homologues of the maize TERMINAL EAR1 gene in Poaceae were studied. This gene encodes an RNA-binding motif (RRM) protein, that is suggested to regulate leaf initiation. Using degenerate primers, one unique tel (terminal ear1-like) gene from seven Poaceae members, covering almost all the phylogenetic tree of the family, was identified by PCR. These genes present a very high degree of similarity, a much conserved exon-intron structure, and the three RRMs and TEL characteristic motifs. The evolution of tel sequences in Poaceae strongly correlates with the known phylogenetic tree of this family. RT-PCR gene expression analyses show conserved tel expression in the shoot apex in all species, suggesting functional orthology between these genes. In addition, in situ hybridization experiments with specific antisense probes show tel transcript accumulation in all differentiating cells of the leaf, from the recruitment of leaf founder cells to leaf margins cells. Tel expression is not restricted to initiating leaves as it is also found in pro-vascular tissues, root meristems, and immature inflorescences. Therefore, these results suggest that TEL is not only associated with leaf initiation but more generally with cell differentiation in Poaceae.

Mother-infant joint attention and sharing: relations to disorganized attachment and maternal disrupted communication.

PubMed

Annie Yoon, Seungyeon; Kelso, Gwendolyn A; Lock, Anna; Lyons-Ruth, Karlen

2014-01-01

The normative development of infant shared attention has been studied extensively, but few studies have examined the impact of disorganized attachment and disturbed maternal caregiving on mother-infant shared attention. The authors examined both maternal initiations of joint attention and infants' responses to those initiations during the reunion episodes of the Strange Situation Procedure at 12 and 18 months of infant age. The mothers' initiations of joint attention and three forms of infant response, including shunning, simple joint attention, and sharing attention, were examined in relation to infant disorganized attachment and maternal disrupted communication. Mothers who were disrupted in communication with their infants at 18 months initiated fewer bids for joint attention at 12 months, and, at 18 months, mothers of infants classified disorganized initiated fewer bids. However, the infant' responses were unrelated to either the infant' or the mother' disturbed attachment. At both ages, disorganized infants and infants of disrupted mothers were as likely to respond to maternal bids as were their lower risk counterparts. Our results suggest that a disposition to share experiences with others is robust in infancy, even among infants with adverse attachment experiences, but this infant disposition may depend on adult initiation of bids to be realized.

Benchmark eye movement effects during natural reading in autism spectrum disorder.

PubMed

Howard, Philippa L; Liversedge, Simon P; Benson, Valerie

2017-01-01

In 2 experiments, eye tracking methodology was used to assess on-line lexical, syntactic and semantic processing in autism spectrum disorder (ASD). In Experiment 1, lexical identification was examined by manipulating the frequency of target words. Both typically developed (TD) and ASD readers showed normal frequency effects, suggesting that the processes TD and ASD readers engage in to identify words are comparable. In Experiment 2, syntactic parsing and semantic interpretation requiring the on-line use of world knowledge were examined, by having participants read garden path sentences containing an ambiguous prepositional phrase. Both groups showed normal garden path effects when reading low-attached sentences and the time course of reading disruption was comparable between groups. This suggests that not only do ASD readers hold similar syntactic preferences to TD readers, but also that they use world knowledge on-line during reading. Together, these experiments demonstrate that the initial construction of sentence interpretation appears to be intact in ASD. However, the finding that ASD readers skip target words less often in Experiment 2, and take longer to read sentences during second pass for both experiments, suggests that they adopt a more cautious reading strategy and take longer to evaluate their sentence interpretation prior to making a manual response. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Is there something quantum-like about the human mental lexicon?

PubMed Central

Bruza, Peter; Kitto, Kirsty; Nelson, Douglas; McEvoy, Cathy

2010-01-01

Following an early claim by Nelson & McEvoy (35) suggesting that word associations can display ‘spooky action at a distance behaviour’, a serious investigation of the potentially quantum nature of such associations is currently underway. In this paper quantum theory is proposed as a framework suitable for modelling the human mental lexicon, specifically the results obtained from both intralist and extralist word association experiments. Some initial models exploring this hypothesis are discussed, and experiments capable of testing these models proposed. PMID:20224806

Temporal Planning for Compilation of Quantum Approximate Optimization Algorithm Circuits

NASA Technical Reports Server (NTRS)

Venturelli, Davide; Do, Minh Binh; Rieffel, Eleanor Gilbert; Frank, Jeremy David

2017-01-01

We investigate the application of temporal planners to the problem of compiling quantum circuits to newly emerging quantum hardware. While our approach is general, we focus our initial experiments on Quantum Approximate Optimization Algorithm (QAOA) circuits that have few ordering constraints and allow highly parallel plans. We report on experiments using several temporal planners to compile circuits of various sizes to a realistic hardware. This early empirical evaluation suggests that temporal planning is a viable approach to quantum circuit compilation.

Modeling the temporal variability of zinc concentrations in zinc roof runoff-experimental study and uncertainty analysis.

PubMed

Sage, Jérémie; El Oreibi, Elissar; Saad, Mohamed; Gromaire, Marie-Christine

2016-08-01

This study investigates the temporal variability of zinc concentrations from zinc roof runoff. The influence of rainfall characteristics and dry period duration is evaluated by combining laboratory experiment on small zinc sheets and in situ measurements under real weather conditions from a 1.6-m(2) zinc panel. A reformulation of a commonly used conceptual runoff quality model is introduced and its ability to simulate the evolution of zinc concentrations is evaluated. A systematic and sharp decrease from initially high to relatively low and stable zinc concentrations after 0.5 to 2 mm of rainfall is observed for both experiments, suggesting that highly soluble corrosion products are removed at early stages of runoff. A moderate dependence between antecedent dry period duration and the magnitude of zinc concentrations at the beginning of a rain event is evidenced. Contrariwise, results indicate that concentrations are not significantly influenced by rainfall intensities. Simulated rainfall experiment nonetheless suggests that a slight effect of rainfall intensities may be expected after the initial decrease of concentrations. Finally, this study shows that relatively simple conceptual runoff quality models may be adopted to simulate the variability of zinc concentrations during a rain event and from a rain event to another.

Using a hybrid model to predict solute transfer from initially saturated soil into surface runoff with controlled drainage water.

PubMed

Tong, Juxiu; Hu, Bill X; Yang, Jinzhong; Zhu, Yan

2016-06-01

The mixing layer theory is not suitable for predicting solute transfer from initially saturated soil to surface runoff water under controlled drainage conditions. By coupling the mixing layer theory model with the numerical model Hydrus-1D, a hybrid solute transfer model has been proposed to predict soil solute transfer from an initially saturated soil into surface water, under controlled drainage water conditions. The model can also consider the increasing ponding water conditions on soil surface before surface runoff. The data of solute concentration in surface runoff and drainage water from a sand experiment is used as the reference experiment. The parameters for the water flow and solute transfer model and mixing layer depth under controlled drainage water condition are identified. Based on these identified parameters, the model is applied to another initially saturated sand experiment with constant and time-increasing mixing layer depth after surface runoff, under the controlled drainage water condition with lower drainage height at the bottom. The simulation results agree well with the observed data. Study results suggest that the hybrid model can accurately simulate the solute transfer from initially saturated soil into surface runoff under controlled drainage water condition. And it has been found that the prediction with increasing mixing layer depth is better than that with the constant one in the experiment with lower drainage condition. Since lower drainage condition and deeper ponded water depth result in later runoff start time, more solute sources in the mixing layer are needed for the surface water, and larger change rate results in the increasing mixing layer depth.

Teacher Professional Development to Foster Authentic Student Research Experiences

NASA Astrophysics Data System (ADS)

Conn, K.; Iyengar, E.

2004-12-01

This presentation reports on a new teacher workshop design that encourages teachers to initiate and support long-term student-directed research projects in the classroom setting. Teachers were recruited and engaged in an intensive marine ecology learning experience at Shoals Marine Laboratory, Appledore Island, Maine. Part of the weeklong summer workshop was spent in field work, part in laboratory work, and part in learning experimental design and basic statistical analysis of experimental results. Teachers were presented with strategies to adapt their workshop learnings to formulate plans for initiating and managing authentic student research projects in their classrooms. The authors will report on the different considerations and constraints facing the teachers in their home school settings and teachers' progress in implementing their plans. Suggestions for replicating the workshop will be offered.

Women Clerical Workers: Sex-Role Socialization, Work Attitudes, and Values.

ERIC Educational Resources Information Center

Pearson, Hilary M.; Kahn, Sharon E.

1989-01-01

Explored differences in sex-role socialization, personality orientation, and work attitudes and values of two groups of women clerical workers (N=91) who made their initial career choices in different historical time frames (the 1950s and 1970s). Results suggest that women clerical workers with differing sex-role socialization experiences may have…

Body Dissatisfaction, Ethnic Identity, and Disordered Eating among African American Women

ERIC Educational Resources Information Center

Rogers Wood, Nikel A.; Petrie, Trent A.

2010-01-01

Initial research suggested that only European American women developed eating disorders (Garner, 1993), yet recent studies have shown that African American women do experience them (e.g., Lester & Petrie, 1998b; Mulholland & Mintz, 2001) and also may be negatively affected by similar sociocultural variables. In this study, we examined a…

An Analysis of the Time Course of Lexical Processing during Reading

ERIC Educational Resources Information Center

Sheridan, Heather; Reichle, Erik D.

2016-01-01

Reingold, Reichle, Glaholt, and Sheridan (2012) reported a gaze-contingent eye-movement experiment in which survival-curve analyses were used to examine the effects of word frequency, the availability of parafoveal preview, and initial fixation location on the time course of lexical processing. The key results of these analyses suggest that…

Refugee Children's Adaptation to American Early Childhood Classrooms: A Narrative Inquiry

ERIC Educational Resources Information Center

Prior, Megan A.; Niesz, Tricia

2013-01-01

Researchers have suggested that a paucity of research exists on refugee youth in early childhood education settings. Arguing that children's stories provide educators a valuable resource for understanding the meaning children make of initial cross-cultural experiences, this article presents a narrative inquiry into the stories and artwork of three…

Supporting Law Students' Skills Development Online--A Strategy to Improve Skills and Reduce Student Stress?

ERIC Educational Resources Information Center

Hewitt, Anne; Stubbs, Matthew

2017-01-01

Law students internationally suffer from a high level of psychological distress compared with the general and student populations, and anecdotal evidence suggests that students developing skills without adequate support experience significant stress and anxiety. This article considers an initiative at one Australian law school to develop a…

Toward an Interactive Analogy Model of Reading Development: Decoding Vowel Graphemes in Beginning Reading.

ERIC Educational Resources Information Center

Goswami, Usha

1993-01-01

Three experiments on vowel decoding involving primary school children partially tested an interactive model of reading acquisition. The model suggests that children begin learning to read by establishing orthographic recognition units for words that have phonological underpinning that is initially at the onset-rime level but that becomes…

Why Inquiry Is Inherently Difficult...and Some Ways to Make It Easier

ERIC Educational Resources Information Center

Meyer, Daniel Z.; Avery, Leanne M.

2010-01-01

In this article, the authors offer a framework that identifies two critical problems in designing inquiry-based instruction and suggests three models for developing instruction that overcomes those problems. The Protocol Model overcomes the Getting on Board Problem by providing students an initial experience through clearly delineated steps with a…

Planting the Seed of Teacher Identity: Nurturing Early Growth through a Collaborative Learning Community

ERIC Educational Resources Information Center

Harlow, Ann; Cobb, Donella J.

2014-01-01

This paper reports on the findings of a reconceptualised Initial Teacher Education (ITE) programme where a collaborative relationship between the university and partner schools saw the shared responsibility for the first year ITE programme. Findings from this study suggests that ongoing, authentic teaching experiences in collaboration with…

Exploring the Influences on Classroom-Based Contact via Shared Education in Northern Ireland

ERIC Educational Resources Information Center

Loader, Rebecca

2017-01-01

Initiatives in intercultural education have frequently involved the promotion of contact between members of different groups as a means of improving intergroup relations. Experience from Northern Ireland suggests, however, that such schemes have often been organised and delivered in such a way that opportunities for sustained, high-quality contact…

EFL and Educational Reform: Content-Based Instruction in Argentina.

ERIC Educational Resources Information Center

Snow, Marguerite Ann; Cortes, Viviana; Pron, Alejandra V.

1998-01-01

Discusses initial experiences with content-based instruction in Argentina. The new approach was precipitated in part by educational reform. Suggests that the dramatic shift from a grammar-based approach to a communicative approach, and the use of language as a tool for instruction may become overwhelming for most teachers. (Author/VWL)

A purified transcription factor (TIF-IB) binds to essential sequences of the mouse rDNA promoter.

PubMed Central

Clos, J; Buttgereit, D; Grummt, I

1986-01-01

A transcription factor that is specific for mouse rDNA has been partially purified from Ehrlich ascites cells. This factor [designated transcription initiation factor (TIF)-IB] is required for accurate in vitro synthesis of mouse rRNA in addition to RNA polymerase I and another regulatory factor, TIF-IA. TIF-IB activity is present in extracts both from growing and nongrowing cells in comparable amounts. Prebinding competition experiments with wild-type and mutant templates suggest that TIF-IB interacts with the core control element of the rDNA promoter, which is located immediately upstream of the initiation site. The specific binding of TIF-IB to the RNA polymerase I promoter is demonstrated by exonuclease III protection experiments. The 3' border of the sequences protected by TIF-IB is shown to be on the coding strand at position -21 and on the noncoding strand at position -7. The results suggest that direct binding of TIF-IB to sequences in the core promoter element is the mechanism by which this factor imparts promoter selectivity to RNA polymerase I. Images PMID:3456157

Evaluating Niger's experience in strengthening supervision, improving availability of child survival drugs through cost recovery, and initiating training for Integrated Management of Childhood Illness (IMCI)

PubMed Central

Tawfik, Youssef M; Legros, Stephane; Geslin, Colette

2001-01-01

Background WHO and UNICEF have recently developed the "Integrated Management of Childhood Illness" (IMCI) as an efficient strategy to assist developing countries reduce childhood mortality. Early experience with IMCI implementation suggests that clinical training is essential but not sufficient for the success of the strategy. Attention needs to be given to strengthening health systems, such as supervision and drug supply. Results This paper presents results of evaluating an innovative approach for implementing IMCI in Niger. It starts with strengthening district level supervision and improving the availability of child survival drugs through cost recovery well before the beginning of IMCI clinical training. The evaluation documented the effectiveness of the initial IMCI clinical training and referral. Conclusions Strengthening supervision and assuring the availability of essential drugs need to precede the initiation of IMCI Clinical training. Longer term follow up is necessary to confirm the impact of the approach on IMCI preparation and implementation. PMID:11504567

Rhythmic grouping biases constrain infant statistical learning

PubMed Central

Hay, Jessica F.; Saffran, Jenny R.

2012-01-01

Linguistic stress and sequential statistical cues to word boundaries interact during speech segmentation in infancy. However, little is known about how the different acoustic components of stress constrain statistical learning. The current studies were designed to investigate whether intensity and duration each function independently as cues to initial prominence (trochaic-based hypothesis) or whether, as predicted by the Iambic-Trochaic Law (ITL), intensity and duration have characteristic and separable effects on rhythmic grouping (ITL-based hypothesis) in a statistical learning task. Infants were familiarized with an artificial language (Experiments 1 & 3) or a tone stream (Experiment 2) in which there was an alternation in either intensity or duration. In addition to potential acoustic cues, the familiarization sequences also contained statistical cues to word boundaries. In speech (Experiment 1) and non-speech (Experiment 2) conditions, 9-month-old infants demonstrated discrimination patterns consistent with an ITL-based hypothesis: intensity signaled initial prominence and duration signaled final prominence. The results of Experiment 3, in which 6.5-month-old infants were familiarized with the speech streams from Experiment 1, suggest that there is a developmental change in infants’ willingness to treat increased duration as a cue to word offsets in fluent speech. Infants’ perceptual systems interact with linguistic experience to constrain how infants learn from their auditory environment. PMID:23730217

Classification of adults with problematic internet experiences: linking internet and conventional problems from a clinical perspective.

PubMed

Mitchell, Kimberly J; Finkelhor, David; Becker-Blease, Kathryn A

2007-06-01

This article utilizes data from clinical reports of 929 adults to examine whether various problematic Internet experiences are distinctly different from or extensions of conventional problems. A TwoStep Cluster Analysis identified three mutually exclusive groups of adults, those with (1) online relationship problems and victimization; (2) online and offline problems; and (3) marital discord. Results suggest some initial support for the idea that problematic Internet experiences are often extensions of experiences and behaviors that pre-date the Internet. However, the Internet may be introducing some qualitatively new dimensions-such as an increased severity, an increased frequency, or unique dynamics-that require new responses or interventions.

Discrepancy detection in the retrieval-enhanced suggestibility paradigm.

PubMed

Butler, Brendon Jerome; Loftus, Elizabeth F

2018-04-01

Retrieval-enhanced suggestibility (RES) refers to the finding that immediately recalling the details of a witnessed event can increase susceptibility to later misinformation. In three experiments, we sought to gain a deeper understanding of the role that retrieval plays in the RES paradigm. Consistent with past research, initial testing did increase susceptibility to misinformation - but only for those who failed to detect discrepancies between the original event and the post-event misinformation. In all three experiments, subjects who retrospectively detected discrepancies in the post-event narratives were more resistant to misinformation than those who did not. In Experiments 2 and 3, having subjects concurrently assess the consistency of the misinformation narratives negated the RES effect. Interestingly, in Experiments 2 and 3, subjects who had retrieval practice and detected discrepancies were more likely to endorse misinformation than control subjects who detected discrepancies. These results call attention to limiting conditions of the RES effect and highlight the complex relationship between retrieval practice, discrepancy detection, and misinformation endorsement.

Is frictional heating needed to cause dramatic weakening of nanoparticle gouge during seismic slip? Insights from friction experiments with variable thermal evolutions

NASA Astrophysics Data System (ADS)

Yao, Lu; Ma, Shengli; Niemeijer, André R.; Shimamoto, Toshihiko; Platt, John D.

2016-07-01

To examine whether faults can be lubricated by preexisting and newly formed nanoparticles, we perform high-velocity friction experiments on periclase (MgO) nanoparticles and on bare surfaces of Carrara marble cylinders/slices, respectively. Variable temperature conditions were simulated by using host blocks of different thermal conductivities. When temperature rises are relatively low, we observe high friction in nano-MgO tests and unexpected slip strengthening following initial weakening in marble slice tests, suggesting that the dominant weakening mechanisms are of thermal origin. Solely the rolling of nanoparticles without significant temperature rise is insufficient to cause dynamic fault weakening. For nano-MgO experiments, comprehensive investigations suggest that flash heating is the most likely weakening mechanism. In marble experiments, flash heating controls the unique evolutions of friction, and the competition between bulk temperature rise and wear-induced changes of asperity contact numbers seems to strongly affect the efficiency of flash heating.

Understanding Performance Decrements in a Letter-Canceling Task: Overcoming Habits or Inhibition of Reading.

PubMed

Myers, Larry; Downie, Steven; Taylor, Grant; Marrington, Jessica; Tehan, Gerald; Ireland, Michael J

2018-01-01

The importance of self-regulation in human behavior is readily apparent and diverse theoretical accounts for explaining self-regulation failures have been proposed. Typically, these accounts are based on a sequential task methodology where an initial task is presented to deplete self-regulatory resources, and carryover effects are then examined on a second outcome task. In the aftermath of high profile replication failures using a popular letter-crossing task as a means of depleting self-regulatory resources and subsequent criticisms of that task, current research into self-control is currently at an impasse. This is largely due to the lack of empirical research that tests explicit assumptions regarding the initial task. One such untested assumption is that for resource depletion to occur, the initial task must first establish an habitual response and then this habitual response must be inhibited, with behavioral inhibition being the causal factor in inducing depletion. This study reports on four experiments exploring performance on a letter-canceling task, where the rules for target identification remained constant but the method of responding differed (Experiment 1) and the coherence of the text was manipulated (Experiments 1-4). Experiment 1 established that habit forming and behavioral inhibition did not produce any performance decrement when the targets were embedded in random letter strings. Experiments 2-4 established that target detection was sensitive to language characteristics and the coherence of the background text, suggesting that participants' automatic reading processes is a key driver of performance in the letter-e task.

Adverse childhood experiences predict earlier age of drinking onset: results from a representative US sample of current or former drinkers.

PubMed

Rothman, Emily F; Edwards, Erika M; Heeren, Timothy; Hingson, Ralph W

2008-08-01

Our goal was to determine whether adverse childhood experiences predicted the age at which drinking was initiated and drinking motives in a representative sample of current or former drinkers in the United States. In 2006, a probability sample of 3592 US current or former drinkers aged 18 to 39 were surveyed. Multinomial logistic regression examined whether each of 10 adverse childhood experiences was associated with earlier ages of drinking onset, controlling for demographics, parental alcohol use, parental attitudes toward drinking, and peers' drinking in adolescence. We also examined whether there was a graded relationship between the number of adverse childhood experiences and age of drinking onset and whether adverse childhood experiences were related to self-reported motives for drinking during the first year that respondents drank. Sixty-six percent of respondents reported >or=1 adverse childhood experiences, and 19% reported experiencing >or=4. The most commonly reported adverse childhood experiences were parental separation/divorce (41.3%), living with a household member who was a problem drinker (28.7%), mental illness of a household member (24.8%), and sexual abuse (19.1%). Of the 10 specific adverse childhood experiences assessed, 5 were significantly associated with initiating drinking at or=21 years of age) after adjustment for confounders, including physical abuse, sexual abuse, having a mentally ill household member, substance abuse in the home, and parental discord or divorce. Compared with those without adverse childhood experiences, respondents with adverse childhood experiences were substantially more likely to report that they drank to cope during the first year that they used alcohol. Results suggest that children with particular adverse childhood experiences may initiate drinking earlier than their peers and that they may be more likely to drink to cope with problems (rather than for pleasure or to be social).

An enquiry into the process of categorization of pictures and words.

PubMed

Viswanathan, Madhubalan; Childers, Terry L

2003-02-01

This paper reports a series of experiments conducted to study the categorization of pictures and words. Whereas some studies reported in the past have found a picture advantage in categorization, other studies have yielded no differences between pictures and words. This paper used an experimental paradigm designed to overcome some methodological problems to examine picture-word categorization. The results of one experiment were consistent with an advantage for pictures in categorization. To identify the source of the picture advantage in categorization, two more experiments were conducted. Findings suggest that semantic relatedness may play an important role in the categorization of both pictures and words. We explain these findings by suggesting that pictures simultaneously access both their concept and visually salient features whereas words may initially access their concept and may subsequently activate features. Therefore, pictures have an advantage in categorization by offering multiple routes to semantic processing.

Initiation Processes of the Tropical Intraseasonal Variability Simulated in an Aqua-Planet Experiment: What is the Intrinsic Mechanism for MJO Onset?

NASA Astrophysics Data System (ADS)

Takasuka, Daisuke; Satoh, Masaki; Miyakawa, Tomoki; Miura, Hiroaki

2018-04-01

To understand the intrinsic onset mechanism of the Madden-Julian Oscillation (MJO), we simulated a set of initiation processes of MJO-like disturbances in 10 year aqua-planet experiments using a global atmospheric model with a 56 km horizontal mesh and an explicit cloud scheme. Under a condition with a zonally nonuniform sea surface temperature (SST) in the tropics, we reproduced MJO-like disturbances over the western warm pool region. The lagged-composite analysis of detected MJO-like disturbances clarifies the time sequence of three-dimensional dynamic and moisture fields prior to the onset. We found that midtropospheric moistening, a condition that is favorable for deep convection, is particularly obvious in the initiation region 5-9 days before onset. The moistening is caused by two-dimensional horizontal advection due to cross-equatorial shallow circulations associated with mixed Rossby-gravity waves, as well as anomalous poleward flows of a negative Rossby response to suppressed convection. When the midtroposphere is sufficiently moistened, lower tropospheric signals of circumnavigating Kelvin waves trigger active convection. The surface latent heat flux (LHF) feedback contributes to the initial stages of convective organization, while the cloud-radiation feedback contributes to later stages. Sensitivity experiments suggest that circumnavigating Kelvin waves regulate the period of MJO-like disturbances because of efficient convective triggering and that the LHF feedback contributes to rapid convective organization. However, the experiments also reveal that both conditions are not necessary for the existence of MJO-like disturbances. Implications for the relevance of these mechanisms for MJO onset are also discussed.

Perception of resyllabification in French.

PubMed

Gaskell, M Gareth; Spinelli, Elsa; Meunier, Fanny

2002-07-01

In three experiments, we examined the effects of phonological resyllabification processes on the perception of French speech. Enchainment involves the resyllabification of a word-final consonant across a syllable boundary (e.g., in chaque avion, the /k/ crosses the syllable boundary to become syllable initial). Liaison involves a further process of realization of a latent consonant, alongside resyllabification (e.g., the /t/ in petit avion). If the syllable is a dominant unit of perception in French (Mehler, Dommergues, Frauenfelder, & Segui, 1981), these processes should cause problems for recognition of the following word. A cross-modal priming experiment showed no cost attached to either type of resyllabification in terms of reduced activation of the following word. Furthermore, word- and sequence-monitoring experiments again showed no cost and suggested that the recognition of vowel-initial words may be facilitated when they are preceded by a word that had undergone resyllabification through enchainment or liaison. We examine the sources of information that could underpin facilitation and propose a refinement of the syllable's role in the perception of French speech.

Effects of intravenous dimethyl sulfoxide on ischemia evolution in a rat permanent occlusion model

PubMed Central

Bardutzky, Juergen; Meng, Xianjun; Bouley, James; Duong, Timothy Q; Ratan, Rajiv; Fisher, Marc

2010-01-01

Dimethyl sulfoxide (DMSO) has a variety of biological actions that suggest efficacy as a neuroprotectant. We (1) tested the neuroprotective potential of DMSO at different time windows on infarct size using 2,3,5-triphenyltetrazolium staining and (2) investigated the effects of DMSO on ischemia evolution using quantitative diffusion and perfusion imaging in a permanent middle cerebral artery occlusion (MCAO) model in rats. In experiment 1, DMSO treatment (1.5 g/kg intravenously over 3 h) reduced infarct volume 24 h after MCAO by 65% (P<0.00001) when initiated 20 h before MCAO, by 44% (P=0.0006) when initiated 1 h after MCAO, and by 17% (P=0.11) when started 2 h after MCAO. Significant infarct reduction was also observed after a 3-day survival in animals treated 1 h after MCAO (P=0.005). In experiment 2, treatment was initiated 1 h after MCAO and maps for cerebral blood flow (CBF) and apparent diffusion coefficient (ADC) were acquired before treatment and then every 30 mins up to 4 h. Cerebral blood flow characteristics and CBF-derived lesion volumes did not differ between treated and untreated animals, whereas the ADC-derived lesion volume essentially stopped progressing during DMSO treatment, resulting in a persistent diffusion/perfusion mismatch. This effect was mainly observed in the cortex. Our data suggest that DMSO represents an interesting candidate for acute stroke treatment. PMID:15744247

Still at the choice-point: action selection and initiation in instrumental conditioning.

PubMed

Balleine, Bernard W; Ostlund, Sean B

2007-05-01

Contrary to classic stimulus-response (S-R) theory, recent evidence suggests that, in instrumental conditioning, rats encode the relationship between their actions and the specific consequences that these actions produce. It has remained unclear, however, how encoding this relationship acts to control instrumental performance. Although S-R theories were able to give a clear account of how learning translates into performance, the argument that instrumental learning constitutes the acquisition of information of the form "response R leads to outcome O" does not directly imply a particular performance rule or policy; this information can be used both to perform R and to avoid performing R. Recognition of this problem has forced the development of accounts that allow the O and stimuli that predict the O (i.e., S-O) to play a role in the initiation of specific Rs. In recent experiments, we have used a variety of behavioral procedures in an attempt to isolate the processes that contribute to instrumental performance, including outcome devaluation, reinstatement, and Pavlovian-instrumental transfer. Our results, particularly from experiments assessing outcome-selective reinstatement, suggest that both "feed-forward" (O-R) and "feed-back" (R-O) associations are critical and that although the former appear to be important to response selection, the latter-together with processes that determine outcome value-mediate response initiation. We discuss a conceptual model that integrates these processes and its neural implementation.

OC35 - Child Friendly Healthcare Initiative, implementation project in a paediatric department in Greece.

PubMed

Boutopoulou, Barbara; Clarke, Andrew; Christothanopoulou, Ioanna; Douros, Konstantinos; Tsirouda, Maria; Papaevangelou, Vasiliki

2016-05-09

Theme: Accreditation and quality improvement. Child Friendly Healthcare Initiative (CFHI) aims to improve quality of experience and health care given to children and families by improving realisation of children's rights and reducing unnecessary fear, anxiety and suffering during and because of health care. To present results of preliminary CFH assessment. Implementation was initiated in a paediatric department of a University Hospital in Athens, Greece, consisting of a 37-bed ward, Outpatient Clinic and Emergency Department. For the preliminary assessment of the CFHI tool No1, which is for parents-caregiverschildren and health workers, this was translated into Greek. 112 parents-caregivers and six children were interviewed by an independent interviewer. In total, 24 health workers - 5 paediatricians, 11 residents and 8 nurses - responded to the CFHI tool No 1. Issues highlighted were mostly about CFH Standard 3 and Standard 7. Suggestions for improvement in all Standards were suggested. Preliminary assessment revealed the quality of care needs improvement. The next step is the training health workers, planning and making improvements.

Continuous track paths reveal additive evidence integration in multistep decision making.

PubMed

Buc Calderon, Cristian; Dewulf, Myrtille; Gevers, Wim; Verguts, Tom

2017-10-03

Multistep decision making pervades daily life, but its underlying mechanisms remain obscure. We distinguish four prominent models of multistep decision making, namely serial stage, hierarchical evidence integration, hierarchical leaky competing accumulation (HLCA), and probabilistic evidence integration (PEI). To empirically disentangle these models, we design a two-step reward-based decision paradigm and implement it in a reaching task experiment. In a first step, participants choose between two potential upcoming choices, each associated with two rewards. In a second step, participants choose between the two rewards selected in the first step. Strikingly, as predicted by the HLCA and PEI models, the first-step decision dynamics were initially biased toward the choice representing the highest sum/mean before being redirected toward the choice representing the maximal reward (i.e., initial dip). Only HLCA and PEI predicted this initial dip, suggesting that first-step decision dynamics depend on additive integration of competing second-step choices. Our data suggest that potential future outcomes are progressively unraveled during multistep decision making.

Temperature requirements for initiation of RNA-dependent RNA polymerization.

PubMed

Yang, Hongyan; Gottlieb, Paul; Wei, Hui; Bamford, Dennis H; Makeyev, Eugene V

2003-09-30

To continue the molecular characterization of RNA-dependent RNA polymerases of dsRNA bacteriophages (Cystoviridae), we purified and biochemically characterized the wild-type (wt) and a temperature-sensitive (ts) point mutant of the polymerase subunit (Pol) from bacteriophage phi12. Interestingly, initiation by both wt and the ts phi12 Pol was notably more sensitive to increased temperatures than the elongation step, the absolute value of the nonpermissive temperature being lower for the ts enzyme. Experiments with the Pol subunit of related cystovirus phi6 revealed a similar differential sensitivity of the initiation and elongation steps. This is consistent with the previous result showing that de novo initiation by RdRp from dengue virus is inhibited at elevated temperatures, whereas the elongation phase is relatively thermostable. Overall, these data suggest that de novo RNA-dependent RNA synthesis in many viral systems includes a specialized thermolabile state of the RdRp initiation complex.

The importance of fluctuations in fluid mixing.

PubMed

Kadau, Kai; Rosenblatt, Charles; Barber, John L; Germann, Timothy C; Huang, Zhibin; Carlès, Pierre; Alder, Berni J

2007-05-08

A ubiquitous example of fluid mixing is the Rayleigh-Taylor instability, in which a heavy fluid initially sits atop a light fluid in a gravitational field. The subsequent development of the unstable interface between the two fluids is marked by several stages. At first, each interface mode grows exponentially with time before transitioning to a nonlinear regime characterized by more complex hydrodynamic mixing. Unfortunately, traditional continuum modeling of this process has generally been in poor agreement with experiment. Here, we indicate that the natural, random fluctuations of the flow field present in any fluid, which are neglected in continuum models, can lead to qualitatively and quantitatively better agreement with experiment. We performed billion-particle atomistic simulations and magnetic levitation experiments with unprecedented control of initial interface conditions. A comparison between our simulations and experiments reveals good agreement in terms of the growth rate of the mixing front as well as the new observation of droplet breakup at later times. These results improve our understanding of many fluid processes, including interface phenomena that occur, for example, in supernovae, the detachment of droplets from a faucet, and ink jet printing. Such instabilities are also relevant to the possible energy source of inertial confinement fusion, in which a millimeter-sized capsule is imploded to initiate nuclear fusion reactions between deuterium and tritium. Our results suggest that the applicability of continuum models would be greatly enhanced by explicitly including the effects of random fluctuations.

Corporate social responsibility and hospitals: US theory, Japanese experiences, and lessons for other countries.

PubMed

Takahashi, Toshiro; Ellen, Moriah; Brown, Adalsteinn

2013-01-01

This paper examines the role that corporate social responsibility can play in advancing hospital management. Corporate social responsibility is the integration of social and environmental concerns within business operations. The authors discuss how corporate social responsibility can help hospitals and provide suggestions to hospitals in deciding which corporate social responsibility initiatives to pursue.

Exploring the Impact of Global Studies Experiences on Undergraduate Student Development: Some Curricular Considerations

ERIC Educational Resources Information Center

Stephens, Christopher J.; Morford, Z. Harrison; Cihon, Traci M.; Forand, Elissa Hamilton; Neri-Hernández, Lucero

2018-01-01

In this manuscript, the authors detail the initial evaluations of the effects of participation in two iterations of an interdisciplinary learning community with a short-term study abroad opportunity on undergraduate student learning and behavior. The results suggest that the CHE (Cultural, Historical, and Environmental) log tool may be useful in…

Challenges for Supporting the Development of Afterschool Tutors Who Tutor Children with Learning Disabilities

ERIC Educational Resources Information Center

McLurkin, Denise L.

2013-01-01

The purpose of my study was to examine how volunteer tutors without teaching experience who received minimal training perceived their ability to effectively tutor children with learning disabilities. I found that the tutors initially felt that they could improve their tutee's literacy skills; however, the data suggest that the tutors…

The Transition to Kindergarten for Typically Developing Children: A Survey of School Psychologists' Involvement

ERIC Educational Resources Information Center

McIntyre, Laura Lee; Eckert, Tanya L.; Arbolino, Lauren A.; DiGennaro Reed, Florence D.; Fiese, Barbara H.

2014-01-01

Research suggests that a large percentage of kindergarten children do not successfully transition to school (Rimm-Kaufman et al. 2000). As a result, a number of school transition initiatives have been developed by educators and policy makers to address the difficulties young children may experience upon kindergarten entry. Despite this attention,…

The association between the oxytocin receptor gene (OXTR) and hypnotizability.

PubMed

Bryant, Richard A; Hung, Lynette; Dobson-Stone, Carol; Schofield, Peter R

2013-10-01

Hypnosis has puzzled scientists for centuries, and particularly the reason why some people are prone to engaging in suggested experiences discordant with external reality. Absorption in internal experience is one key component of the hypnotic response. The neuropeptide oxytocin has been posited to heighten sensitivity to external cues, and it is possible that individual differences in oxytocin-related capacity to engage in external or internal experiences influences hypnotic response. To test this proposal, 185 Caucasian individuals provided saliva samples for analysis of polymorphisms in the oxytocin receptor gene, COMT, and independently completed standardized measures of hypnotizability and absorption. Participants with the GG genotype at rs53576 were characterized by lower hypnotizability and absorption scores than those with the A allele; there was no association between hyponotizability and COMT. These findings provide initial evidence that the capacity to respond to suggestions for altered internal experience is influenced by the oxytocin receptor gene, and is consistent with evidence that oxytocin plays an important role in modulating the extent to which people engage with external versus internal experiences. Copyright © 2013 Elsevier Ltd. All rights reserved.

Methane-related metabolisms of deep-sea sediments captured with a colonization experiment.

NASA Astrophysics Data System (ADS)

Carr, S. A.; Wheat, C. G.; Orcutt, B.; Kopf, A.; Saffer, D. M.; Toczko, S.

2016-12-01

NanTroSEIZE is a multi-expedition project of the International Ocean Discovery Program (IODP) designed to investigate the Nankai Trough subduction zone. In 2016, a long-term borehole instrument package known as the "GeniusPlug" was collected from Hole C0010A after a six-year deployment within the sediment of a major fault zone, at a depth of 400 mbsf. This GeniusPlug included a set of osmotically-driven pumps, which continuously pumped in situ deep seated, formation water through a microbiological colonization experiment (flow-through osmo colonization system (FLOCS)). This FLOCS experiment contained cassettes of olivine, barite, and sediment collected from nearby Hole C0004D, to serve as colonization substrates. While similar FLOCS have been deployed within boreholes in the igneous oceanic crust, this FLOCS experiment represents the first to be deployed within a sedimentary environment, and thus represents the first opportunity to observe how pore water communities colonize sediment and rock substrates. Initial geochemistry results suggest that conditions within the FLOCS experiment were similar to a methane-sulfate transition zone, and initial enrichment cultures inoculated with the FLOCS substrates demonstrate methane production. Here, we will present integrated results of culturing experiments and culture-independent genomic investigations as a means to elucidate the methane-related metabolisms of these colonizing communities.

Effect of supplemental sodium chloride and hydrochloric acid added to initial starter diets containing spray-dried blood plasma and lactose on resulting performance and nitrogen digestibility of 3-week-old weaned pigs.

PubMed

Mahan, D C; Wiseman, T D; Weaver, E; Russell, L

1999-11-01

Four experiments evaluated the efficacy of Na or Cl or their combination added to weanling pig diets that contained plasma protein and lactose on pig performance and N digestibility. The four experiments used a total of 563 crossbred pigs weaned at 22+/-1 d of age averaging 6.4 kg body weight. The basal diet in each experiment contained 5.8% plasma protein and 20% lactose and analyzed .20% Na and .23% Cl. In Exp. 1, NaCl was added to treatment diets at 0, .20, .40, or .60%. The trial was conducted for a 21 d period in a randomized complete block (RCB) design in seven replicates. Improved growth rates (P < .01) and gain:feed ratios (P < .01) occurred up to a dietary salt level of .40%. In Exp. 2, we evaluated the interaction of Na and Cl on pig performance. The experiment was a 2 x 2 factorial arrangement in a RCB design conducted in seven replicates. Total dietary Na was .20 or .36%, and Cl was included at .25 or .45%. Although there was a numerical increase in pig gains with added Na, the response was not significant (P > .15), but both gains (P < .01) and gain:feed ratios (P < .01) increased at the higher dietary Cl level. In Exp. 3, we evaluated the effect of five dietary levels of Cl added at .06% increments to a basal diet that analyzed .34% Na and .20% Cl on postweaning pig performance. The experiment was a RCB design conducted in eight replicates. A growth response (P < .01) to the .38% Cl level occurred during the initial 14-d postweaning period and to the .32% Cl level from 14 to 21 d. Gain:feed ratio increased each week with added Cl, but it was significant only for the period from d 0 to 7 d (P < .01). A N digestibility trial, using the diets of Exp. 3, constituted Exp. 4, and groups of three pigs per stainless steel metabolism crate were pair-fed to pigs fed the basal diet. The experiment was a RCB design conducted in three replicates over a 3-wk period. The results demonstrated a weekly decrease in fecal N (P < .01), no effect on urinary N (P < .15), improved N retention (P < .01), and an improved apparent N digestibility (P < .01) to the .38% dietary Cl concentration during the initial 2 wk postweaning. These experiments suggest that although plasma protein contributed Na and Cl to the initial diets of weaned pigs, additional Na and Cl, but particularly Cl, improved pig growth, N retention, and N digestibility. The results suggest a dietary minimum of .38% total Cl level during the initial 2 wk postweaning.

Chloroplast Osmotic Adjustment and Water Stress Effects on Photosynthesis 1

PubMed Central

Gupta, Ashima Sen; Berkowitz, Gerald A.

1988-01-01

Previous studies have suggested that chloroplast stromal volume reduction may mediate the inhibition of photosynthesis under water stress. In this study, the effects of spinach (Spinacia oleracea, var `Winter Bloomsdale') plant water deficits on chloroplast photosynthetic capacity, solute concentrations in chloroplasts, and chloroplast volume were studied. In situ (gas exchange) and in vitro measurements indicated that chloroplast photosynthetic capacity was maintained during initial leaf water potential (Ψw) and relative water content (RWC) decline. During the latter part of the stress period, photosynthesis dropped precipitously. Chloroplast stromal volume apparently remained constant during the initial period of decline in RWC, but as leaf Ψw reached −1.2 megapascals, stromal volume began to decline. The apparent maintenance of stromal volume over the initial RWC decline during a stress cycle suggested that chloroplasts are capable of osmotic adjustment in response to leaf water deficits. This hypothesis was confirmed by measuring chloroplast solute levels, which increased during stress. The results of these experiments suggest that stromal volume reduction in situ may be associated with loss of photosynthetic capacity and that one mechanism of photosynthetic acclimation to low Ψw may involve stromal volume maintenance. PMID:16666266

Anticipatory balance control is affected by loadless training experiences.

PubMed

Robert, G; Gueguen, N; Avogadro, P; Mouchnino, L

2004-09-01

The main purpose of this study was to identify whether a lot of sports training had any effect on the balance control associated with a leg movement. The nature of the training experience was also an important concern and we chose subject who had undergone specific training experience in absence of equilibrium constraints. To this end a comparison between control (untrained) subjects, triathletes and swimmers was designed to establish whether a general training in sports (triathletes) or a specific loadless training (swimmers), leads to differences in the balance control. A leg movement is preceded by a shift of the center of mass (CM) towards the supporting side to maintain equilibrium and forward to create the condition for progression. To provide an acceleration of the CM sideward and forward, an initial displacement of the center of pressure (CP) towards the moving limb and in posterior direction was performed. Interestingly, the lateral pressure onto the ground was greater increased in swimmers in both leg raising and obstacle avoidance tasks compared to the control group and/or triathletes whereas the backward CP shift in all group was the same. The initial control of the CM shift is very different in swimmers compared to triathletes and controls. The increased lateral pressure onto the ground in swimmers may be a result of a prolonged training in water. This suggests that prolonged training in the absence of equilibrium constraints has more of an effect on balance control than a prolonged general training. In addition, the lack of differences in the backward CP shift suggests that M/L and A/P controls support two functional goals: equilibrium maintenance and movement initiation.

Adolescent Work, Vocational Development, and Education

PubMed Central

Zimmer-Gembeck, Melanie J.; Mortimer, Jeylan T.

2006-01-01

This review examines contemporary issues in vocational development with emphasis on adolescents’ work experiences in social context. Attention is directed to the changing social and cultural context for vocational development, the influence of work experience on adolescent development and educational achievement, and theoretical approaches that guide contemporary studies of vocational development and career maturity. In light of the utility of current theories, new directions are suggested to enhance understanding of adolescent employment, vocational development, and educational pursuits. Social policy initiatives to promote adolescents’ exercise of agency and their vocational development are considered. PMID:17387375

Self-compassion increases self-improvement motivation.

PubMed

Breines, Juliana G; Chen, Serena

2012-09-01

Can treating oneself with compassion after making a mistake increase self-improvement motivation? In four experiments, the authors examined the hypothesis that self-compassion motivates people to improve personal weaknesses, moral transgressions, and test performance. Participants in a self-compassion condition, compared to a self-esteem control condition and either no intervention or a positive distraction control condition, expressed greater incremental beliefs about a personal weakness (Experiment 1); reported greater motivation to make amends and avoid repeating a recent moral transgression (Experiment 2); spent more time studying for a difficult test following an initial failure (Experiment 3); exhibited a preference for upward social comparison after reflecting on a personal weakness (Experiment 4); and reported greater motivation to change the weakness (Experiment 4). These findings suggest that, somewhat paradoxically, taking an accepting approach to personal failure may make people more motivated to improve themselves.

EFFECTS OF INTERVIEWER BEHAVIOR ON ACCURACY OF CHILDREN'S RESPONSES

PubMed Central

Sparling, Jessica; Wilder, David A; Kondash, Jennifer; Boyle, Megan; Compton, Megan

2011-01-01

Previous research has shown that certain interviewer behaviors can evoke inaccurate answers by children. In the current study, we examined the effects of approving and disapproving statements on the accuracy of 3 children's answers to questions in an interview (Experiment 1). We then evaluated 3 questioning techniques that may be used by interviewers during a forensic interview in which a child provides eyewitness testimony (Experiment 2). All participants responded with more inaccurate answers when approving statements followed inaccurate information and disapproving statements followed accurate information in Experiment 1. During Experiment 2, 1 participant responded most inaccurately when she was requestioned after providing an initial answer, whereas the remaining 2 participants responded most inaccurately when the interviewer provided cowitness information and suggestive questions. PMID:21941387

Low-cost vibration sensor based on dual fiber Bragg gratings and light intensity measurement.

PubMed

Gao, Xueqing; Wang, Yongjiao; Yuan, Bo; Yuan, Yinquan; Dai, Yawen; Xu, Gang

2013-09-20

A vibration monitoring system based on light intensity measurement has been constructed, and the designed accelerometer is based on steel cantilever frame and dual fiber Bragg gratings (FBGs). By using numerical simulations for the dual FBGs, the dependence relationship of the area of main lobes on the difference of initial central wavelengths is obtained and the most optimal choice for the initial value and the vibration amplitude of the difference of central wavelengths of two FBGs is suggested. The vibration monitoring experiments are finished, and the measured data are identical to the simulated results.

Low Lunar Orbit Design via Graphical Manipulation of Eccentricity Vector Evolution

NASA Technical Reports Server (NTRS)

Wallace, Mark S.; Sweetser, Theodore H.; Roncoli, Ralph B.

2012-01-01

Low lunar orbits, such as those used by GRAIL and LRO, experience predictable variations in the evolution of their eccentricity vectors. These variations are nearly invariant with respect to the initial eccentricity and argument of periapse and change only in the details with respect to the initial semi-major axis. These properties suggest that manipulating the eccentricity vector evolution directly can give insight into orbit maintenance designs and can reduce the number of propagations required. A trio of techniques for determining the desired maneuvers is presented in the context of the GRAIL extended mission.

Suggested Interactivity: Seeking Perceived Affordances for Information Visualization.

PubMed

Boy, Jeremy; Eveillard, Louis; Detienne, Françoise; Fekete, Jean-Daniel

2016-01-01

In this article, we investigate methods for suggesting the interactivity of online visualizations embedded with text. We first assess the need for such methods by conducting three initial experiments on Amazon's Mechanical Turk. We then present a design space for Suggested Interactivity (i. e., visual cues used as perceived affordances-SI), based on a survey of 382 HTML5 and visualization websites. Finally, we assess the effectiveness of three SI cues we designed for suggesting the interactivity of bar charts embedded with text. Our results show that only one cue (SI3) was successful in inciting participants to interact with the visualizations, and we hypothesize this is because this particular cue provided feedforward.

Failure to obtain value enhancement by within-trial contrast in simultaneous and successive discriminations.

PubMed

Arantes, Joana; Grace, Randolph C

2008-02-01

The present research tested the generality of the "work ethic" effect described by Clement, Feltus, Kaiser, and Zentall (2000). In Experiment 1, we trained 10 pigeons on a pair of either simultaneous or successive discriminations. One discrimination followed a high-effort requirement (20 pecks to the center key) and the other followed a low-effort requirement (1 peck). Contrary to Clement et al.'s results, we found that preferences between the S+ and S- stimuli in transfer tests depended on the event that initiated the trial: Pigeons preferred the stimulus from the baseline discrimination whose initiating event was most dissimilar from that preceding the test trial. Preferences were similar but less extreme in the successive condition. In Experiment 2, we investigated whether test preferences depended on the amount of training. A total of 12 pigeons were trained on a pair of simultaneous discriminations, except that test sessions were scheduled after every three baseline sessions. Preferences increased across test sessions but were similar to those in Experiment 1. Together with Vasconcelos, Urcuioli, and Lionello-DeNolf (2007a), our study represents a second failure to replicate Clement et al.'s work ethic effect. The finding that preference depends on the event that initiates the test trial suggests that choice probes may not provide unambiguous assessments of stimulus value.

Learning to throw on a rotating carousel: recalibration based on limb dynamics and projectile kinematics.

PubMed

Bruggeman, Hugo; Pick, Herbert L; Rieser, John J

2005-05-01

Skilled actions exhibit adjustment in calibration to bring about their goals. The sought-after calibrations change as a function of the environmental situation that stages the actions. In these experiments participants sat on one side of a rotating carousel and threw beanbags underhanded at a target fixed on the opposite side. Logically, aimed throwing in this situation involves adjustment to fit changes in limb dynamics (originating from Coriolis forces) and changes in perceived projectile kinematics (originating from the tangential velocity of thrower and target). We studied whether such adjustment involved one or multiple components of recalibration. An initial experiment showed that exposure to rotation while throwing beanbags produced a robust recalibration in the direction of underhanded throws as manifest in throwing at stationary targets from a stationary position. Following some initial decay this recalibration persisted and approached an asymptote. Subsequent experiments suggested two independent components of recalibration. One is based on limb dynamics and accounts for the initial decay. The other is based on the perceived projectile kinematics and accounts for the stable change in throwing direction. These results raised the question of how multiple components of recalibration of an action are related. We propose that movement components are independent and calibrated separately at different levels in the organization of an action.

Nurses and stress: recognizing causes and seeking solutions.

PubMed

Happell, Brenda; Dwyer, Trudy; Reid-Searl, Kerry; Burke, Karena J; Caperchione, Cristina M; Gaskin, Cadeyrn J

2013-05-01

To identify, from the perspectives of nurses, occupational stressors and ways in which they may be reduced. Nurses commonly experience high levels of occupational stress, with negative consequences for their physical and psychological health, health-care organisations and community. There is minimal research on reducing occupational stress. Six focus groups were conducted with 38 registered nurses using a qualitative exploratory approach. Participants were asked to identify sources of occupational stress and possible workplace initiatives to reduce stress. Sources of occupational stress were: high workloads, unavailability of doctors, unsupportive management, human resource issues, interpersonal issues, patients' relatives, shift work, car parking, handover procedures, no common area for nurses, not progressing at work and patient mental health. Suggestions for reduction included: workload modification, non-ward-based initiatives, changing shift hours, forwarding suggestions for change, music, special events, organisational development, ensuring nurses get breaks, massage therapists, acknowledgement from management and leadership within wards. The findings highlight the need to understand local perspectives and the importance of involving nurses in identifying initiatives to reduce occupational stress. Health-care environments can be enhanced through local understanding of the occupational stressors and productively engaging nurses in developing stress reduction initiatives. Nurse managers must facilitate such processes. © 2013 Blackwell Publishing Ltd.

Considerations for Community-Based mHealth Initiatives: Insights From Three Beacon Communities

PubMed Central

2013-01-01

Mobile health (mHealth) is gaining widespread attention for its potential to engage patients in their health and health care in their daily lives. Emerging evidence suggests that mHealth interventions can be used effectively to support behavior change, but numerous challenges remain when implementing these programs at the community level. This paper provides an overview of considerations when implementing community-based mHealth initiatives, based on the experiences of three Beacon Communities across the United States that have launched text messaging (short message service, SMS) pilot programs aimed at diabetes risk reduction and disease management. The paper addresses lessons learned and suggests strategies to overcome challenges related to developing text message content, conducting marketing and outreach, enrolling participants, engaging providers, evaluating program effectiveness, and sustaining and scaling the programs. PMID:24128406

Regeneration of Patch Harvests in Even-Aged Northern Hardwoods in New England

Treesearch

William B. Leak

2003-01-01

One suggested approach to converting even-aged northern hardwoods to an uneven-aged condition is the use of small-patch harvests to initiate new regeneration of desired species. Past experience indicates that such harvests may be less successful in second-growth, even-aged stands than in olderstands due to the abundance of sprouts and noncommercial species....

Swedish Teachers' Ethical Reflections on a Study Visit to Central America

ERIC Educational Resources Information Center

Sund, Louise; Öhman, Johan

2014-01-01

In this article we argue that culturally variable values and morals have a key role in educational initiatives that address a global dimension. The article suggests that looking at values and morals in relation to a teaching practice is a way of adding knowledge to this field. Our study inquires into how an intercultural experience can evoke…

Positioning Australia's Contemporary Health and Physical Education Curriculum to Address Poor Physical Activity Participation Rates by Adolescent Girls

ERIC Educational Resources Information Center

Usher, Wayne; Edwards, Allan; Cudmore, Laura

2016-01-01

Background: Given the wealth of research identifying how schools are in a strong position to promote physical activity (PA) among children, it would be reasonable to suggest that initial experiences of physical education and school sport are critical factors influencing whether a student will develop a healthy relationship to PA. However, research…

Early-Time HANE Simulation and Experiment

DTIC Science & Technology

1987-05-01

we suggest attacking the question of structure with target variation. Irregular structure in laboratory simulations of HANE’s can arise from...plasma instabilities even when the illuminating laser beam and target are optimized to yield a very uniform initial expansion. Irregularities ... irregular structure be purposely explored. In particular we encourage the use of a wide variety of inhomogeneous targets. Target irregularities

Leadership for Student Learning: Redefining the Teacher as Leader. School Leadership for the 21st Century Initiative. A Report of the Task Force on Teacher Leadership.

ERIC Educational Resources Information Center

Institute for Educational Leadership, Washington, DC.

This report presents information from discussions by the Institute for Educational Leadership Task Force on Teacher Leadership, highlighting dilemmas surrounding teacher leadership and suggesting that education's policymakers should exploit the experience and capacity to lead today's schoolteachers. Overall, the system has not been organized to…

Factors Associated with Partnership Experiences, Attitudes, and Perceptions: A Comparative Case Study of Two African Universities

ERIC Educational Resources Information Center

Chiteng Kot, Felly

2011-01-01

International partnerships have become an increasingly important trend in African higher education. The creation of partnerships with African universities has been on the rise in the last few years. Different factors (U.S., European, and African initiatives) suggest this trend will continue to increase. This study draws from a survey of a random…

Why do participants initiate free recall of short lists of words with the first list item? Toward a general episodic memory explanation.

PubMed

Spurgeon, Jessica; Ward, Geoff; Matthews, William J

2014-11-01

Participants who are presented with a short list of words for immediate free recall (IFR) show a strong tendency to initiate their recall with the 1st list item and then proceed in forward serial order. We report 2 experiments that examined whether this tendency was underpinned by a short-term memory store, of the type that is argued by some to underpin recency effects in IFR. In Experiment 1, we presented 3 groups of participants with lists of between 2 and 12 words for IFR, delayed free recall, and continuous-distractor free recall. The to-be-remembered words were simultaneously spoken and presented visually, and the distractor task involved silently solving a series of self-paced, visually presented mathematical equations (e.g., 3 + 2 + 4 = ?). The tendency to initiate recall at the start of short lists was greatest in IFR but was also present in the 2 other recall conditions. This finding was replicated in Experiment 2, where the to-be-remembered items were presented visually in silence and the participants spoke aloud their answers to computer-paced mathematical equations. Our results necessitate that a short-term buffer cannot be fully responsible for the tendency to initiate recall from the beginning of a short list; rather, they suggest that the tendency represents a general property of episodic memory that occurs across a range of time scales. PsycINFO Database Record (c) 2014 APA, all rights reserved.

Buildings, Beauty, and the Brain: A Neuroscience of Architectural Experience.

PubMed

Coburn, Alex; Vartanian, Oshin; Chatterjee, Anjan

2017-09-01

A burgeoning interest in the intersection of neuroscience and architecture promises to offer biologically inspired insights into the design of spaces. The goal of such interdisciplinary approaches to architecture is to motivate construction of environments that would contribute to peoples' flourishing in behavior, health, and well-being. We suggest that this nascent field of neuroarchitecture is at a pivotal point in which neuroscience and architecture are poised to extend to a neuroscience of architecture. In such a research program, architectural experiences themselves are the target of neuroscientific inquiry. Here, we draw lessons from recent developments in neuroaesthetics to suggest how neuroarchitecture might mature into an experimental science. We review the extant literature and offer an initial framework from which to contextualize such research. Finally, we outline theoretical and technical challenges that lie ahead.

Phonological universals constrain the processing of nonspeech stimuli.

PubMed

Berent, Iris; Balaban, Evan; Lennertz, Tracy; Vaknin-Nusbaum, Vered

2010-08-01

Domain-specific systems are hypothetically specialized with respect to the outputs they compute and the inputs they allow (Fodor, 1983). Here, we examine whether these 2 conditions for specialization are dissociable. An initial experiment suggests that English speakers could extend a putatively universal phonological restriction to inputs identified as nonspeech. A subsequent comparison of English and Russian participants indicates that the processing of nonspeech inputs is modulated by linguistic experience. Striking, qualitative differences between English and Russian participants suggest that they rely on linguistic principles, both universal and language-particular, rather than generic auditory processing strategies. Thus, the computation of idiosyncratic linguistic outputs is apparently not restricted to speech inputs. This conclusion presents various challenges to both domain-specific and domain-general accounts of cognition. 2010 APA, all rights reserved

Anatomy and humanity: Examining the effects of a short documentary film and first anatomy laboratory experience on medical students.

PubMed

Dosani, Farah; Neuberger, Lindsay

2016-01-01

Medical students begin their education inside a laboratory dissecting cadavers to learn human gross anatomy. Many schools use the course experience as a way to instill empathy and some have begun integrating video and recorded interviews with body donors to humanize the experience, but their impact has yet to be measured. This study examines the effects of a brief documentary film and the initial cadaver encounter on student perceptions and attitudes towards the laboratory experience. A pre-test, exposure, post-test design was used with 77 first-year medical students at the University of Central Florida. A previously validated questionnaire was adapted to measure attitudes, emotions, initial reaction to cadaver, perception of the donor as a person, and impressions of the film. An online questionnaire was completed before the first day of laboratory, in which students watched the film Anatomy and Humanity and handled their respective cadavers (no dissection was performed). The post-test was administered immediately following the activities of the first laboratory day. Results indicate an increase in negative attitudes towards dissection, but a more positive initial reaction to the cadaver than originally anticipated. Students also experienced a decrease in emotions like sadness and guilt regarding anatomy laboratory and were less likely to view the cadaver as a once-living person. Findings suggest a higher comfort level, but also greater detachment toward the cadavers from day one despite the video intervention. These results provide novel insight that may aid other interventions aimed at promoting humanism in the anatomy laboratory experience. © 2015 American Association of Anatomists.

Concentrating on beauty: sexual selection and sociospatial memory.

PubMed

Becker, D Vaughn; Kenrick, Douglas T; Guerin, Stephen; Maner, Jon K

2005-12-01

In three experiments, location memory for faces was examined using a computer version of the matching game Concentration. Findings suggested that physical attractiveness led to more efficient matching for female faces but not for male faces. Study 3 revealed this interaction despite allowing participants to initially see, attend to, and match the attractive male faces in the first few turns. Analysis of matching errors suggested that, compared to other targets, attractive women were less confusable with one another. Results are discussed in terms of the different functions that attractiveness serves for men and women.

Clay-clast aggregates: A new textural evidence for seismic fault sliding?

NASA Astrophysics Data System (ADS)

Boutareaud, Sébastien; Calugaru, Dan-Gabriel; Han, Raehee; Fabbri, Olivier; Mizoguchi, Kazuo; Tsutsumi, Akito; Shimamoto, Toshihiko

2008-03-01

To determine the processes responsible for slip-weakening in clayey gouge zones, rotary-shear experiments were conducted at seismic slip rates (equivalent to 0.9 and 1.3 m/s) at 0.6 MPa normal stress on a natural clayey gouge for saturated and non-saturated initial conditions. The mechanical behavior of the simulated faults shows a reproducible slip-weakening behavior, whatever initial moisture conditions. Examination of gouge obtained at the residual friction stage in saturated and non-saturated initial conditions allows the definition of two types of microstructures: a foliated type reflecting strain localization, and a non-foliated type composed of spherical aggregates. Friction experiments demonstrate that liquid-vapor transition of water within gouge due to frictional heating has a high capacity to explain the formation of spherical aggregates in the first meters of displacement. This result suggests that the occurrence of spherical aggregates in natural clayey fault gouges can constitute a new textural evidence for shallow depth pore water phase transition at seismic slip velocity and consequently for past seismic fault sliding.

Worklife Improvement and Leadership Development study: a learning experience in leadership development and "planned" organizational change.

PubMed

Cummings, Greta G; Spiers, Judith A; Sharlow, Janice; Germann, Paula; Yurtseven, Ozden; Bhatti, Aslam

2013-01-01

In response to increasing recognition of the importance of quality health care work environments, the Alberta Cancer Board initiated a province-wide leadership development program to plan for organizational change through a series of stages. In 2004, the Leadership Development Initiative (LDI) was implemented to facilitate organizational learning using a cohort-based leadership intervention based on a communities of practice framework. The aim of the Worklife Improvement and Leadership Development study was to examine both the outcomes and experiences of participants of the LDI program to better understand leadership development, implementation, and its impact on worklife quality among 5 cohorts of health care managers and staff at the Alberta Cancer Board. This study used both structured survey and interview methods, using a pretest-intervention-posttest quasi-experiment without a control group design, to assess the effects of LDI on worklife of leaders and staff. Surveys included the Leadership Practices Inventory and Areas of Worklife Scale, which looked at meaningfulness of work and organizational engagement. Interviews and focus group data provided a more detailed description of the experience of leadership development and perceptions of organizational worklife. The study revealed layers of information about the complexity of individual and collective leadership in a cohort-based design, perceptions of leadership initiatives, organizational worklife, and planned organizational change. Our findings suggest that early changes in how leaders reflected on their own skills and practices (Leading Self) were positive; however, growing disengagement as the LDI continued was evident in the focus group data, particularly when change in behavior of others was not perceived to be evident. To support the effectiveness and success of a leadership initiative, managers and administrators need to implement strategies designed to help leaders grow and cope with ongoing flux of organizational change and stagnation.

Target-object integration, attention distribution, and object orientation interactively modulate object-based selection.

PubMed

Al-Janabi, Shahd; Greenberg, Adam S

2016-10-01

The representational basis of attentional selection can be object-based. Various studies have suggested, however, that object-based selection is less robust than spatial selection across experimental paradigms. We sought to examine the manner by which the following factors might explain this variation: Target-Object Integration (targets 'on' vs. part 'of' an object), Attention Distribution (narrow vs. wide), and Object Orientation (horizontal vs. vertical). In Experiment 1, participants discriminated between two targets presented 'on' an object in one session, or presented as a change 'of' an object in another session. There was no spatial cue-thus, attention was initially focused widely-and the objects were horizontal or vertical. We found evidence of object-based selection only when targets constituted a change 'of' an object. Additionally, object orientation modulated the sign of object-based selection: We observed a same-object advantage for horizontal objects, but a same-object cost for vertical objects. In Experiment 2, an informative cue preceded a single target presented 'on' an object or as a change 'of' an object (thus, attention was initially focused narrowly). Unlike in Experiment 1, we found evidence of object-based selection independent of target-object integration. We again found that the sign of selection was modulated by the objects' orientation. This result may reflect a meridian effect, which emerged due to anisotropies in the cortical representations when attention is oriented endogenously. Experiment 3 revealed that object orientation did not modulate object-based selection when attention was oriented exogenously. Our findings suggest that target-object integration, attention distribution, and object orientation modulate object-based selection, but only in combination.

Lecithotrophic behaviour in zoea and megalopa larvae of the ghost shrimp Lepidophthalmus siriboia Felder and Rodrigues, 1993 (Decapoda: Callianassidae).

PubMed

Abrunhosa, Fernando A; Simith, Darlan J B; Palmeira, Carlos A M; Arruda, Danielle C B

2008-12-01

Food supply is considered critical for a successful culturing of decapod larvae. However, some species may present yolk reserve sufficient to complete their larval development without external food supply (known as lecithotrophic larval development). In the present study, two experiments were carried out in order to verify whether the callianassid Lepidophthalmus siriboia have lecithotrophic behaviour or, if they need external food for their larval development: Experiment 1, larvae submitted to an initial feeding period and Experiment 2, larvae submitted to an initial starvation period. High survival rate was observed in both experiments, in which only 2 megalopae and 1 zoea III died. These results strongly suggest that larvae of L. siriboia are lecithotrophic as they have sufficiently large yolk reserve to complete their larval development, while the megalopa stage shows facultative lecithotrophy. The larval periods of each stage of the treatments were quite similar and, despite some significant differences in some larval periods, these can be related probably to larval rearing conditions, abiotic factors or, individual variability of larval health, as well as stress caused to the ovigerous females during embryogenesis.

Bundled Payments for Care Improvement

PubMed Central

Hardin, Lauran; Kilian, Adam; Murphy, Elizabeth

2017-01-01

BACKGROUND The Centers for Medicare and Medicaid Services Innovation Center introduced the Bundled Payments for Care Improvement (BPCI) initiative in 2011 as 1 strategy to encourage healthcare organizations and clinicians to improve healthcare delivery for patients, both when they are in the hospital and after they are discharged. Mercy Health Saint Mary’s, a large urban academic medical center, engaged in BPCI primarily with a group of medical diagnosis-related groups (DRGs). OBJECTIVES In this article, we describe our experience creating a system of response for the diverse people and diagnoses that fall into the medical DRG bundles and specifically identify organizational factors for enabling successful implementation of bundled payments. RESULTS Our experience suggests that interprofessional collaboration enabled program success. CONCLUSIONS Although still in its early phases, observations from our program’s strategies and tactics may provide potential insights for organizations considering engagement in the BPCI initiative. PMID:28509721

Experiments with a Parallel Multi-Objective Evolutionary Algorithm for Scheduling

NASA Technical Reports Server (NTRS)

Brown, Matthew; Johnston, Mark D.

2013-01-01

Evolutionary multi-objective algorithms have great potential for scheduling in those situations where tradeoffs among competing objectives represent a key requirement. One challenge, however, is runtime performance, as a consequence of evolving not just a single schedule, but an entire population, while attempting to sample the Pareto frontier as accurately and uniformly as possible. The growing availability of multi-core processors in end user workstations, and even laptops, has raised the question of the extent to which such hardware can be used to speed up evolutionary algorithms. In this paper we report on early experiments in parallelizing a Generalized Differential Evolution (GDE) algorithm for scheduling long-range activities on NASA's Deep Space Network. Initial results show that significant speedups can be achieved, but that performance does not necessarily improve as more cores are utilized. We describe our preliminary results and some initial suggestions from parallelizing the GDE algorithm. Directions for future work are outlined.

Sorption and desorption of lead (II) from wastewater by green algae Cladophora fascicularis.

PubMed

Deng, Liping; Su, Yingying; Su, Hua; Wang, Xinting; Zhu, Xiaobin

2007-05-08

Biosorption is an effective method to remove heavy metals from wastewater. In this work, adsorption features of Cladophora fascicularis were investigated as a function of time, initial pH, initial Pb(II) concentrations, temperature and co-existing ions. Kinetics and equilibria were obtained from batch experiments. The biosorption kinetics followed the pseudo-second order model. Adsorption equilibria were well described by the Langmuir and Freundlich isotherm models. The maximum adsorption capacity was 198.5 mg/g at 298K and pH 5.0. The adsorption processes were endothermic and the biosorption heat was 29.6 kJ/mol. Desorption experiments indicated that 0.01 mol/L Na(2)EDTA was an efficient desorbent for the recovery of Pb(II) from biomass. IR spectrum analysis suggested amido or hydroxy, CO and C-O could combine intensively with Pb(II).

Tropical forecasting - Predictability perspective

NASA Technical Reports Server (NTRS)

Shukla, J.

1989-01-01

Results are presented of classical predictability studies and forecast experiments with observed initial conditions to show the nature of initial error growth and final error equilibration for the tropics and midlatitudes, separately. It is found that the theoretical upper limit of tropical circulation predictability is far less than for midlatitudes. The error growth for a complete general circulation model is compared to a dry version of the same model in which there is no prognostic equation for moisture, and diabatic heat sources are prescribed. It is found that the growth rate of synoptic-scale errors for the dry model is significantly smaller than for the moist model, suggesting that the interactions between dynamics and moist processes are among the important causes of atmospheric flow predictability degradation. Results are then presented of numerical experiments showing that correct specification of the slowly varying boundary condition of SST produces significant improvement in the prediction of time-averaged circulation and rainfall over the tropics.

The influence of information status on pronoun resolution in Mandarin Chinese: evidence from ERPs

PubMed Central

Xu, Xiaodong

2015-01-01

The purpose of this study is to shed light on the neural mechanisms underlying the modulation of pronoun resolution processes by the information status of the antecedent. Information status was manipulated by using a structurally based constraint (e.g., order of mention) as well as a pragmatically based constraint (i.e., topichood). We found that the pronouns referring to topic entities [the initial noun phrase (NP) in Subject–Object–Verb (SOV) structure in Experiment 1 and OSV structure in Experiment 2] elicited attenuated P600 responses compared to the pronouns referring to non-topic entities (the initial NP in SVO structure or the second NP in OSV structure in both experiments) when potential interference from structural constraints was controlled. The linear structural constraint, namely the order of mention, had no clear influence on the P600 effect when the syntactic structural constraint was held constant (i.e., when both entities were syntactic subjects), regardless of whether one (Experiment 1) or two (Experiment 2) animate antecedents were present. These findings suggest that pragmatically encoded features such as topichood and givenness can be processed separately from structural constraints such as order of mention to promote the salient status of a referent and thereby facilitate pronoun interpretation. PMID:26217248

Interaction Between Syntactic Structure and Information Structure in the Processing of a Head-Final Language.

PubMed

Koizumi, Masatoshi; Imamura, Satoshi

2017-02-01

The effects of syntactic and information structures on sentence processing load were investigated using two reading comprehension experiments in Japanese, a head-final SOV language. In the first experiment, we discovered the main effects of syntactic and information structures, as well as their interaction, showing that interaction of these two factors is not restricted to head-initial languages. The second experiment revealed that the interaction between syntactic structure and information structure occurs at the second NP (O of SOV and S of OSV), which, crucially, is a pre-head position, suggesting the incremental nature of the processing of both syntactic structure and information structure in head-final languages.

The experience of patients with cancer who develop venous thromboembolism: an exploratory study.

PubMed

Mockler, Alison; O'Brien, Brigit; Emed, Jessica; Ciccotosto, Gina

2012-05-01

To better understand the experience of venous thromboembolism (VTE) from the points of view of patients with cancer during various stages of the cancer experience. Qualitative, descriptive. Various inpatient and outpatient units of a large urban university-affiliated hospital in Montreal, Quebec, Canada. Purposive sample of 10 participants who were anticipating, had recently undergone, or were currently undergoing cancer treatment and who had received a VTE diagnosis within the past year. Semistructured interviews were transcribed verbatim. Thematic analysis of data revealed themes contributing to understanding the lived experience of VTE during cancer care. The experience of patients with cancer who develop VTE. Patients' initial reaction to VTE included VTE as a life-threat, past experience with VTE, and VTE as the "cherry on the sundae" in light of other cancer-related health issues. Patients' coping with VTE also included three themes: VTE being overshadowed by unresolved cancer-related concerns, VTE as a setback in cancer care, and attitudes about VTE treatment. This study contributes new insight into the experience of patients with cancer who develop VTE. The most salient finding was that patients having no prior VTE knowledge experienced VTE as more challenging. Future studies comparing experiences with VTE across the various stages of cancer care are needed. Study findings suggest that patient education about VTE would be useful for the initial reaction and subsequent coping phases of VTE, thus representing an important target area for nursing intervention.

The importance of fluctuations in fluid mixing

PubMed Central

Kadau, Kai; Rosenblatt, Charles; Barber, John L.; Germann, Timothy C.; Huang, Zhibin; Carlès, Pierre; Alder, Berni J.

2007-01-01

A ubiquitous example of fluid mixing is the Rayleigh–Taylor instability, in which a heavy fluid initially sits atop a light fluid in a gravitational field. The subsequent development of the unstable interface between the two fluids is marked by several stages. At first, each interface mode grows exponentially with time before transitioning to a nonlinear regime characterized by more complex hydrodynamic mixing. Unfortunately, traditional continuum modeling of this process has generally been in poor agreement with experiment. Here, we indicate that the natural, random fluctuations of the flow field present in any fluid, which are neglected in continuum models, can lead to qualitatively and quantitatively better agreement with experiment. We performed billion-particle atomistic simulations and magnetic levitation experiments with unprecedented control of initial interface conditions. A comparison between our simulations and experiments reveals good agreement in terms of the growth rate of the mixing front as well as the new observation of droplet breakup at later times. These results improve our understanding of many fluid processes, including interface phenomena that occur, for example, in supernovae, the detachment of droplets from a faucet, and ink jet printing. Such instabilities are also relevant to the possible energy source of inertial confinement fusion, in which a millimeter-sized capsule is imploded to initiate nuclear fusion reactions between deuterium and tritium. Our results suggest that the applicability of continuum models would be greatly enhanced by explicitly including the effects of random fluctuations. PMID:17470811

Swapping horses midstream: factors related to physicians' changing their minds about a diagnosis.

PubMed

Eva, Kevin W; Link, Carol L; Lutfey, Karen E; McKinlay, John B

2010-07-01

Premature closure has been identified as the single most common cause of diagnostic error. This factorial experiment explored which variables exert an unconfounded influence on physicians' diagnostic flexibility (changing their minds about the most likely diagnosis during a clinical case presentation). In 2007-2008, 256 practicing physicians viewed a clinically authentic vignette simulating a patient presenting with possible coronary heart disease (CHD) and provided their initial impression midway through the case. At the end, they answered questions about the case, indicated how they would continue their clinical investigation, and made a final diagnosis. The authors used general linear models to determine which patient factors (age, gender, socioeconomic status, race), physician factors (gender, age/experience), and process variables were related to the likelihood of physicians' changing their minds about the most likely diagnosis. Physicians who had less experience, those who named a non-CHD diagnosis as their initial impression, and those who did not ask for information about the patient's prior cardiac disease history were the most likely to change their minds. Participants' certainty in their initial diagnosis, the additional information desired, the diagnostic hypotheses generated, and the follow-up intended were not related to the likelihood of change in diagnostic hypotheses. Although efforts encouraging physicians to avoid cognitive biases and to reason in a more analytic manner may yield some benefit, this study suggests that experience is a more important determinant of diagnostic flexibility than is the consideration of additional diagnoses or the amount of additional information collected.

The effect of question order on evaluations of test performance: Can the bias dissolve?

PubMed

Bard, Gabriele; Weinstein, Yana

2017-10-01

Question difficulty order has been shown to affect students' global postdictions of test performance. We attempted to eliminate the bias by letting participants experience the question order manipulation multiple times. In all three experiments, participants answered general knowledge questions and self-evaluated their performance. In Experiment 1, participants studied questions and answers in easy-hard or hard-easy question order prior to taking a test in the same order. In Experiment 2, participants took the same test twice in the opposite question order (easy-hard then hard-easy, or hard-easy then easy-hard). In Experiment 3, participants took two different tests in the opposite question order (easy-hard then hard-easy, or hard-easy then easy-hard). In all three experiments, we were unable to eliminate the bias, which suggests that repeated exposure is insufficient to overcome a strong initial anchor.

Melatonin delays clutch initiation in a wild songbird

PubMed Central

Greives, Timothy J.; Kingma, Sjouke A.; Beltrami, Giulia; Hau, Michaela

2012-01-01

The hormone melatonin is known to play an important role in regulating many seasonal changes in physiology, morphology and behaviour. In birds, unlike in mammals, melatonin has thus far been thought to play little role in timing seasonal reproductive processes. This view is mainly derived from laboratory experiments on male birds. This study tests whether melatonin is capable of influencing the timing of clutch initiation in wild female songbirds. Free-living female great tits (Parus major) treated with melatonin-filled implants prior to the breeding season initiated their first clutch of the season significantly later than females carrying an empty implant. Melatonin treatment did not affect clutch size. Further, melatonin treatment did not delay the onset of daily activity in the wild nor adversely affect body mass in captivity compared with controls. These data suggest a previously unknown role for this hormone in regulating the timing of clutch initiation in the wild. PMID:22171024

Model Forecast Skill and Sensitivity to Initial Conditions in the Seasonal Sea Ice Outlook

NASA Technical Reports Server (NTRS)

Blanchard-Wrigglesworth, E.; Cullather, R. I.; Wang, W.; Zhang, J.; Bitz, C. M.

2015-01-01

We explore the skill of predictions of September Arctic sea ice extent from dynamical models participating in the Sea Ice Outlook (SIO). Forecasts submitted in August, at roughly 2 month lead times, are skillful. However, skill is lower in forecasts submitted to SIO, which began in 2008, than in hindcasts (retrospective forecasts) of the last few decades. The multimodel mean SIO predictions offer slightly higher skill than the single-model SIO predictions, but neither beats a damped persistence forecast at longer than 2 month lead times. The models are largely unsuccessful at predicting each other, indicating a large difference in model physics and/or initial conditions. Motivated by this, we perform an initial condition sensitivity experiment with four SIO models, applying a fixed -1 m perturbation to the initial sea ice thickness. The significant range of the response among the models suggests that different model physics make a significant contribution to forecast uncertainty.

Longitudinal relaxation properties of 1HN and 1Hα determined by direct-detected 13C NMR experiments to study intrinsically disordered proteins (IDPs)

NASA Astrophysics Data System (ADS)

Hošek, Tomáš; Gil-Caballero, Sergi; Pierattelli, Roberta; Brutscher, Bernhard; Felli, Isabella C.

2015-05-01

Intrinsically disordered proteins (IDPs) are functional proteins containing large fragments characterized by high local mobility. Bioinformatic studies have suggested that a significant fraction (more than 30%) of eukaryotic proteins has disordered regions of more than 50 amino acids in length. Hence, NMR methods for the characterization of local compactness and solvent accessibility in such highly disordered proteins are of high importance. Among the available approaches, the HET-SOFAST/BEST experiments (Schanda et al., 2006, Rennella et al., 2014) provide semi-quantitative information by monitoring longitudinal 1H relaxation of amide protons under different initial conditions. However, when approaching physiological sample conditions, the potential of these amide 1H detected experiments is reduced due to rapid amide proton solvent exchange. 13C direct detection methods therefore provide a valuable alternative thanks to a higher chemical shift dispersion and their intrinsic insensitivity toward solvent exchange. Here we present two sets of 13C-detected experiments, which indirectly measure 1HN and 1Hα inversion recovery profiles. The experiments consist of an initial spin inversion-recovery block optimized for selective manipulation of different types of proton spins followed by a CON read-out scheme. The proposed experiments were tested on human α-synuclein and ubiquitin, two representative examples of unfolded and folded proteins.

Police-related experiences and HIV risk among female sex workers in Andhra Pradesh, India.

PubMed

Erausquin, Jennifer Toller; Reed, Elizabeth; Blankenship, Kim M

2011-12-01

Research suggests experiences with police are related to human immunodeficiency virus (HIV) sexual risk among women working as sex workers. However, little is known about the links between specific police-related behaviors and HIV vulnerability. We examine whether 5 police-related experiences are associated with measures of HIV risk and violence among a sample of female sex workers (FSWs) in Andhra Pradesh, India, and consider the implications for HIV prevention. FSWs at least 18 years of age (n = 835) were recruited through respondent-driven sampling for a cross-sectional survey conducted as part of Avahan, the India AIDS Initiative. Using logistic regression models adjusted for age, age at start of sex work, and sex work venue, we assessed police-related experiences reported by FSWs in relation to HIV risk behaviors and violence. Results showed having sex with police to avoid trouble, giving gifts to police to avoid trouble, having police take condoms away, experiencing a workplace raid, and being arrested were associated with sexually transmitted infection symptoms, inconsistent condom use, acceptance of more money for sex without a condom, and experience of client violence. These findings suggest a need for interventions targeting police-FSW interactions to reduce HIV vulnerability among FSWs.

Hypercorrection of high confidence errors in lexical representations.

PubMed

Iwaki, Nobuyoshi; Matsushima, Hiroko; Kodaira, Kazumasa

2013-08-01

Memory errors associated with higher confidence are more likely to be corrected than errors made with lower confidence, a phenomenon called the hypercorrection effect. This study investigated whether the hypercorrection effect occurs with phonological information of lexical representations. In Experiment 1, 15 participants performed a Japanese Kanji word-reading task, in which the words had several possible pronunciations. In the initial task, participants were required to read aloud each word and indicate their confidence in their response; this was followed by receipt of visual feedback of the correct response. A hypercorrection effect was observed, indicating generality of this effect beyond previous observations in memories based upon semantic or episodic representations. This effect was replicated in Experiment 2, in which 40 participants performed the same task as in Experiment 1. When the participant's ratings of the practical value of the words were controlled, a partial correlation between confidence and likelihood of later correcting the initial mistaken response was reduced. This suggests that the hypercorrection effect may be partially caused by an individual's recognition of the practical value of reading the words correctly.

Description and evaluation of an initiative to develop advanced practice nurses in mainland China.

PubMed

Wong, Frances Kam Yuet; Peng, Gangyi; Kan, Eva C; Li, Yajie; Lau, Ada T; Zhang, Liying; Leung, Annie F; Liu, Xueqin; Leung, Vilna O; Chen, Weiju; Li, Ming

2010-05-01

This paper describes an initiative to develop Advanced Practice Nurses (APNs) in mainland China and evaluation of the outcomes of the described programme. The pioneer project was an APN postgraduate programme involving 38 students conducted in Guangzhou, China during 2004-2005. Data related to curriculum content and process, student performance, self-reported competence and programme effects were collected. Quantitative data such as demographic data, student performance were analysed using descriptive statistics and the pre and post self-reported practice of competence was compared using chi-square test. Qualitative data such as case reports and interviews were examined using thematic analyses. Reflective journals and case studies revealed the attributes of APNs in managing clinical cases at advanced level, applying theory into practice and exercising evidence-based practice. The relatively modest self-reported practice of competence suggested that the graduates were novice APNs and needed continued development after the completion of the programme. This study reports the experience of an initiative in China and suggests a useful curriculum framework for educating APNs. Copyright 2009 Elsevier Ltd. All rights reserved.

Spatial Updating Strategy Affects the Reference Frame in Path Integration.

PubMed

He, Qiliang; McNamara, Timothy P

2018-06-01

This study investigated how spatial updating strategies affected the selection of reference frames in path integration. Participants walked an outbound path consisting of three successive waypoints in a featureless environment and then pointed to the first waypoint. We manipulated the alignment of participants' final heading at the end of the outbound path with their initial heading to examine the adopted reference frame. We assumed that the initial heading defined the principal reference direction in an allocentric reference frame. In Experiment 1, participants were instructed to use a configural updating strategy and to monitor the shape of the outbound path while they walked it. Pointing performance was best when the final heading was aligned with the initial heading, indicating the use of an allocentric reference frame. In Experiment 2, participants were instructed to use a continuous updating strategy and to keep track of the location of the first waypoint while walking the outbound path. Pointing performance was equivalent regardless of the alignment between the final and the initial headings, indicating the use of an egocentric reference frame. These results confirmed that people could employ different spatial updating strategies in path integration (Wiener, Berthoz, & Wolbers Experimental Brain Research 208(1) 61-71, 2011), and suggested that these strategies could affect the selection of the reference frame for path integration.

Initiation process of a thrust fault revealed by analog experiments

NASA Astrophysics Data System (ADS)

Yamada, Yasuhiro; Dotare, Tatsuya; Adam, Juergen; Hori, Takane; Sakaguchi, Hide

2016-04-01

We conducted 2D (cross-sectional) analog experiments with dry sand using a high resolution digital image correlation (DIC) technique to reveal initiation process of a thrust fault in detail, and identified a number of "weak shear bands" and minor uplift prior to the thrust initiation. The observations suggest that the process can be divided into three stages. Stage 1: characterized by a series of abrupt and short-lived weak shear bands at the location where the thrust will be generated later. Before initiation of the fault, the area to be the hanging wall starts to uplift. Stage 2: defined by the generation of the new thrust and its active displacement. The location of the new thrust seems to be constrained by its associated back-thrust, produced at the foot of the surface slope (by the previous thrust). The activity of the previous thrust turns to zero once the new thrust is generated, but the timing of these two events is not the same. Stage 3: characterized by a constant displacement along the (new) thrust. Similar minor shear bands can be seen in the toe area of the Nankai accretionary prism, SW Japan and we can correlate the along-strike variations in seismic profiles to the model results that show the characteristic features in each thrust development stage.

What Drives a Successful E-Learning? An Empirical Investigation of the Critical Factors Influencing Learner Satisfaction

ERIC Educational Resources Information Center

Sun, Pei-Chen; Tsai, Ray J.; Finger, Glenn; Chen, Yueh-Yang; Yeh, Dowming

2008-01-01

E-Learning is emerging as the new paradigm of modern education. Worldwide, the e-Learning market has a growth rate of 35.6%, but failures exist. Little is known about why many users stop their online learning after their initial experience. Previous research done under different task environments has suggested a variety of factors affecting user…

Investigation of Soil Biodiversity in South East China

NASA Astrophysics Data System (ADS)

Gao, R.; Li, M.; Li, Z.; Chen, Y.; Liang, Y.; Ye, J.

2017-12-01

The United Nations had declared 2015 to be the International Year of Soil to bring to mind the significance of this natural resource. We will describe our initial collaborative effort to investigate soil biodiversity at an organic farm located in South East China. In this session, we will share our early experiences exploring conventional soil biodiversity methods, as well as offer suggestions for future research.

Let Me Count the Ways: Teaching Math in the Library May Seem Like a Stretch. But It's Easier Than You Think

ERIC Educational Resources Information Center

Fleming, Dan

2004-01-01

Based on his personal experience as vice principal of Fuller Middle School and a former school librarian, and participating in a school-wide initiative that focuses on strengthening students' math skills, the author of this article provides suggestions of various ways librarians can integrate math skills into their library lessons. Math is…

Experimental Analysis of Small-Group Performance Effectiveness: Behavioral and Biological Interactions.

DTIC Science & Technology

1982-04-01

processes requiring systematic experimental analysis. Accordingly, group performance effectiveness studies were initiated to 61 assess the effects on...the experiment. 67 active processes associated with Joining the respective established groups, but the absence of baseline levels precludes such an...novitiate in comparison to such values observed during baseline days suggested an active process associated with the joining of the group and emphasized the

Early report: The use of Cytosorb™ haemabsorption column as an adjunct in managing severe sepsis: initial experiences, review and recommendations.

PubMed

Morris, Craig; Gray, Lewis; Giovannelli, Marco

2015-08-01

A novel synthetic haemabsorption column (Cytosorb™) has recently become commercially available. We describe its use in patients with overwhelming sepsis and consider the experience and evidence supporting its use. While Cytosorb haemabsorption is mechanistically distinct from other extracorporeal therapies in sepsis and appears effective in reducing inflammatory cytokines during sepsis, much of the basic science and clinical benefits remain unclear. Significant interactions including removal of antibiotics may be harmful and require further study. Suggestions for future research and how Cytosorb™ could be incorporated into practice are provided.

Early report: The use of Cytosorb™ haemabsorption column as an adjunct in managing severe sepsis: initial experiences, review and recommendations

PubMed Central

Gray, Lewis; Giovannelli, Marco

2015-01-01

A novel synthetic haemabsorption column (Cytosorb™) has recently become commercially available. We describe its use in patients with overwhelming sepsis and consider the experience and evidence supporting its use. While Cytosorb haemabsorption is mechanistically distinct from other extracorporeal therapies in sepsis and appears effective in reducing inflammatory cytokines during sepsis, much of the basic science and clinical benefits remain unclear. Significant interactions including removal of antibiotics may be harmful and require further study. Suggestions for future research and how Cytosorb™ could be incorporated into practice are provided. PMID:28979423

Using evidence-based leadership initiatives to create a healthy nursing work environment.

PubMed

Nayback-Beebe, Ann M; Forsythe, Tanya; Funari, Tamara; Mayfield, Marie; Thoms, William; Smith, Kimberly K; Bradstreet, Harry; Scott, Pamela

2013-01-01

In an effort to create a healthy nursing work environment in a military hospital Intermediate Care Unit (IMCU), a facility-level Evidence Based Practice working group composed of nursing.Stakeholders brainstormed and piloted several unit-level evidence-based leadership initiatives to improve the IMCU nursing work environment. These initiatives were guided by the American Association of Critical Care Nurses Standards for Establishing and Sustaining Healthy Work Environments which encompass: (1) skilled communication, (2) true collaboration, (3) effective decision making, (4) appropriate staffing, (5) meaningful recognition, and (6) authentic leadership. Interim findings suggest implementation of these six evidence-based, relationship-centered principals, when combined with IMCU nurses' clinical expertise, management experience, and personal values and preferences, improved staff morale, decreased staff absenteeism, promoted a healthy nursing work environment, and improved patient care.

The role of neutrophils and monocytic cells in controlling the initiation of Clostridium perfringens gas gangrene.

PubMed

O'Brien, David K; Therit, Blair H; Woodman, Michael E; Melville, Stephen B

2007-06-01

Clostridium perfringens is a common cause of the fatal disease gas gangrene (myonecrosis). Established gas gangrene is notable for a profound absence of neutrophils and monocytic cells (phagocytes), and it has been suggested that the bactericidal activities of these cells play an insignificant role in controlling the progression of the infection. However, large inocula of bacteria are needed to establish an infection in experimental animals, suggesting phagocytes may play a role in inhibiting the initiation of gangrene. Examination of tissue sections of mice infected with a lethal (1 x 10(9)) or sublethal (1 x 10(6)) inoculum of C. perfringens revealed that phagocyte infiltration in the first 3 h postinfection was inhibited with a lethal dose but not with a sublethal dose, indicating that exclusion of phagocytes begins very early in the infection cycle. Experiments in which mice were depleted of either circulating monocytes or neutrophils before infection with C. perfringens showed that monocytes play a role in inhibiting the onset of gas gangrene at intermediate inocula but, although neutrophils can slow the onset of the infection, they are not protective. These results suggest that treatments designed to increase monocyte infiltration and activate macrophages may lead to increased resistance to the initiation of gas gangrene.

Can even-order laser harmonics exhibited by Bohmian trajectories in symmetric potentials be observed?

PubMed

Peatross, J; Johansen, J

2014-01-13

Strong-field laser-atom interactions provide extreme conditions that may be useful for investigating the de Broglie-Bohm quantum interpretation. Bohmian trajectories representing bound electrons in individual atoms exhibit both even and odd harmonic motion when subjected to a strong external laser field. The phases of the even harmonics depend on the random initial positions of the trajectories within the wave function, making the even harmonics incoherent. In contrast, the phases of odd harmonics remain for the most part coherent regardless of initial position. Under the conjecture that a Bohmian point particle plays the role of emitter, this suggests an experiment to determine whether both even and odd harmonics are produced at the atomic level. Estimates suggest that incoherent emission of even harmonics may be detectable out the side of an intense laser focus interacting with a large number of atoms.

The Importance of Interdisciplinary Research Training and Community Dissemination

PubMed Central

Vessali, Misha; Pratt, Jacob A.; Watts, Samantha; Pratt, Janey S.; Raghavan, Preeti; DeSilva, Jeremy M.

2015-01-01

Abstract Funding agencies and institutions are creating initiatives to encourage interdisciplinary research that can be more easily translated into community initiatives to enhance health. Therefore, the current research environment calls for interdisciplinary education and skills to create sustained partnerships with community institutions. However, formalized opportunities in both of these areas are limited for students embarking on research careers. The purpose of this paper is to underscore the historical and current importance of providing interdisciplinary training and community dissemination for research students. We also suggest an approach to begin to address the existing gap. Specifically, we suggest embedding a 10‐week summer rotation into existing research curricula with the goals of: (1) providing students with a hands‐on interdisciplinary research experience, (2) facilitating dialogue between research students and community settings to disseminate science to the public, and (3) sparking collaborations among researchers who seek to create a way to sustain summer program rotations with grant funding. PMID:26508528

Alterations in choice behavior by manipulations of world model.

PubMed

Green, C S; Benson, C; Kersten, D; Schrater, P

2010-09-14

How to compute initially unknown reward values makes up one of the key problems in reinforcement learning theory, with two basic approaches being used. Model-free algorithms rely on the accumulation of substantial amounts of experience to compute the value of actions, whereas in model-based learning, the agent seeks to learn the generative process for outcomes from which the value of actions can be predicted. Here we show that (i) "probability matching"-a consistent example of suboptimal choice behavior seen in humans-occurs in an optimal Bayesian model-based learner using a max decision rule that is initialized with ecologically plausible, but incorrect beliefs about the generative process for outcomes and (ii) human behavior can be strongly and predictably altered by the presence of cues suggestive of various generative processes, despite statistically identical outcome generation. These results suggest human decision making is rational and model based and not consistent with model-free learning.

Alterations in choice behavior by manipulations of world model

PubMed Central

Green, C. S.; Benson, C.; Kersten, D.; Schrater, P.

2010-01-01

How to compute initially unknown reward values makes up one of the key problems in reinforcement learning theory, with two basic approaches being used. Model-free algorithms rely on the accumulation of substantial amounts of experience to compute the value of actions, whereas in model-based learning, the agent seeks to learn the generative process for outcomes from which the value of actions can be predicted. Here we show that (i) “probability matching”—a consistent example of suboptimal choice behavior seen in humans—occurs in an optimal Bayesian model-based learner using a max decision rule that is initialized with ecologically plausible, but incorrect beliefs about the generative process for outcomes and (ii) human behavior can be strongly and predictably altered by the presence of cues suggestive of various generative processes, despite statistically identical outcome generation. These results suggest human decision making is rational and model based and not consistent with model-free learning. PMID:20805507

Organizational change for services integration in public human service organizations: experiences in seven counties.

PubMed

Packard, Thomas; Patti, Rino; Daly, Donna; Tucker-Tatlow, Jennifer

2012-01-01

This is a study of organizational change strategies employed in seven county human service agencies to improve the coordination of services through the structural integration of previously free standing organizations or the development of voluntary interagency collaborative service delivery systems. The central question involves the identification of organizational change tactics which contributed to the success of the organizational change initiatives. The literature on organizational change is reviewed, with particular attention to a framework developed by Fernandez and Rainey based on their extensive review and synthesis of the research on successful change strategies in the public and business sectors. Qualitative and quantitative data were gathered from over 250 individuals and from agency documents. Findings are compared with the success factors identified by Fernandez and Rainey, and refinements to their propositions are suggested. More precise methods for measuring successful and unsuccessful change initiatives are suggested. Implications for practice and research are presented.

Resisting persuasion by the skin of one's teeth: the hidden success of resisted persuasive messages.

PubMed

Tormala, Zakary L; Clarkson, Joshua J; Petty, Richard E

2006-09-01

Recent research has suggested that when people resist persuasion they can perceive this resistance and, under specifiable conditions, become more certain of their initial attitudes (e.g., Z. L. Tormala & R. E. Petty, 2002). Within the same metacognitive framework, the present research provides evidence for the opposite phenomenon--that is, when people resist persuasion, they sometimes become less certain of their initial attitudes. Four experiments demonstrate that when people perceive that they have done a poor job resisting persuasion (e.g., they believe they generated weak arguments against a persuasive message), they lose attitude certainty, show reduced attitude-behavioral intention correspondence, and become more vulnerable to subsequent persuasive attacks. These findings suggest that resisted persuasive attacks can sometimes have a hidden yet important success by reducing the strength of the target attitude. ((c) 2006 APA, all rights reserved).

76 FR 66698 - Postsecondary Educational Institutions Invited To Participate in Experiments Under the...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-10-27

... Experiments Under the Experimental Sites Initiative AGENCY: Office of Postsecondary Education, Department of... institutions to participate in experiments under the Experimental Sites Initiative. SUMMARY: The Secretary... participate in one or more new experiments under the Experimental Sites Initiative (ESI), as authorized by...

Many-body self-localization in a translation-invariant Hamiltonian

NASA Astrophysics Data System (ADS)

Mondaini, Rubem; Cai, Zi

2017-07-01

We study the statistical and dynamical aspects of a translation-invariant Hamiltonian, without quench disorder, as an example of the manifestation of the phenomenon of many-body localization. This is characterized by the breakdown of thermalization and by information preservation of initial preparations at long times. To realize this, we use quasiperiodic long-range interactions, which are now achievable in high-finesse cavity experiments, to find evidence suggestive of a divergent time-scale in which charge inhomogeneities in the initial state survive asymptotically. This is reminiscent of a glassy behavior, which appears in the ground state of this system, being also present at infinite temperatures.

Veterans' experiences initiating VA-based mental health care.

PubMed

Bovin, Michelle J; Miller, Christopher J; Koenig, Christopher J; Lipschitz, Jessica M; Zamora, Kara A; Wright, Patricia B; Pyne, Jeffrey M; Burgess, James F

2018-05-21

Military veterans who could benefit from mental health services often do not access them. Research has revealed a range of barriers associated with initiating United States Department of Veterans Affairs (VA) care, including those specific to accessing mental health care (e.g., fear of stigmatization). More work is needed to streamline access to VA mental health-care services for veterans. In the current study, we interviewed 80 veterans from 9 clinics across the United States about initiation of VA mental health care to identify barriers to access. Results suggested that five predominant factors influenced veterans' decisions to initiate care: (a) awareness of VA mental health services; (b) fear of negative consequences of seeking care; (c) personal beliefs about mental health treatment; (d) input from family and friends; and (e) motivation for treatment. Veterans also spoke about the pathways they used to access this care. The four most commonly reported pathways included (a) physical health-care appointments; (b) the service connection disability system; (c) non-VA care; and (d) being mandated to care. Taken together, these data lend themselves to a model that describes both modifiers of, and pathways to, VA mental health care. The model suggests that interventions aimed at the identified pathways, in concert with efforts designed to reduce barriers, may increase initiation of VA mental health-care services by veterans. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Ego depletion decreases trust in economic decision making

PubMed Central

Ainsworth, Sarah E.; Baumeister, Roy F.; Vohs, Kathleen D.; Ariely, Dan

2014-01-01

Three experiments tested the effects of ego depletion on economic decision making. Participants completed a task either requiring self-control or not. Then participants learned about the trust game, in which senders are given an initial allocation of $10 to split between themselves and another person, the receiver. The receiver receives triple the amount given and can send any, all, or none of the tripled money back to the sender. Participants were assigned the role of the sender and decided how to split the initial allocation. Giving less money, and therefore not trusting the receiver, is the safe, less risky response. Participants who had exerted self-control and were depleted gave the receiver less money than those in the non-depletion condition (Experiment 1). This effect was replicated and moderated in two additional experiments. Depletion again led to lower amounts given (less trust), but primarily among participants who were told they would never meet the receiver (Experiment 2) or who were given no information about how similar they were to the receiver (Experiment 3). Amounts given did not differ for depleted and non-depleted participants who either expected to meet the receiver (Experiment 2) or were led to believe that they were very similar to the receiver (Experiment 3). Decreased trust among depleted participants was strongest among neurotics. These results imply that self-control facilitates behavioral trust, especially when no other cues signal decreased social risk in trusting, such as if an actual or possible relationship with the receiver were suggested. PMID:25013237

Looking the part (to me): effects of racial prototypicality on race perception vary by prejudice

PubMed Central

Sprout, Gregory T.; Freeman, Jonathan B.; Krendl, Anne C.

2017-01-01

Abstract Less racially prototypic faces elicit more category competition during race categorization. Top-down factors (e.g. stereotypes), however, affect categorizations, suggesting racial prototypicality may enhance category competition in certain perceivers. Here, we examined how prejudice affects race category competition and stabilization when perceiving faces varying in racial prototypicality. Prototypically low vs high Black relative to White faces elicited more category competition and slower response latencies during categorization (Experiment 1), suggesting a pronounced racial prototypicality effect on minority race categorization. However, prejudice predicted the extent of category competition between prototypically low vs high Black faces. Suggesting more response conflict toward less prototypic Black vs White faces, anterior cingulate cortex activity increased toward Black vs White faces as they decreased in racial prototypicality, with prejudice positively predicting this difference (Experiment 2). These findings extend the literature on racial prototypicality and categorization by showing that relative prejudice tempers the extent of category competition and response conflict engaged when initially perceiving faces. PMID:28077728

Effects of Direct Social Experience on Trust Decisions and Neural Reward Circuitry

PubMed Central

Fareri, Dominic S.; Chang, Luke J.; Delgado, Mauricio R.

2012-01-01

The human striatum is integral for reward-processing and supports learning by linking experienced outcomes with prior expectations. Recent endeavors implicate the striatum in processing outcomes of social interactions, such as social approval/rejection, as well as in learning reputations of others. Interestingly, social impressions often influence our behavior with others during interactions. Information about an interaction partner’s moral character acquired from biographical information hinders updating of expectations after interactions via top down modulation of reward circuitry. An outstanding question is whether initial impressions formed through experience similarly modulate the ability to update social impressions at the behavioral and neural level. We investigated the role of experienced social information on trust behavior and reward-related BOLD activity. Participants played a computerized ball-tossing game with three fictional partners manipulated to be perceived as good, bad, or neutral. Participants then played an iterated trust game as investors with these same partners while undergoing fMRI. Unbeknownst to participants, partner behavior in the trust game was random and unrelated to their ball-tossing behavior. Participants’ trust decisions were influenced by their prior experience in the ball-tossing game, investing less often with the bad partner compared to the good and neutral. Reinforcement learning models revealed that participants were more sensitive to updating their beliefs about good and bad partners when experiencing outcomes consistent with initial experience. Increased striatal and anterior cingulate BOLD activity for positive versus negative trust game outcomes emerged, which further correlated with model-derived prediction error learning signals. These results suggest that initial impressions formed from direct social experience can be continually shaped by consistent information through reward learning mechanisms. PMID:23087604

Views and Experiences of Malaysian Family Medicine Trainees of Female Sexual Dysfunction.

PubMed

Lai, Pauline Siew Mei; Tan, Sing Yee; Liew, Su May

2016-11-01

Sociocultural factors have been shown to be important influencers of sexual health and sexuality. Hence, the aim of our study was to explore the views and experiences of family medicine trainees regarding female sexual dysfunction (FSD) with a focus on the barriers and facilitators towards the initiation of conversation on this topic. A qualitative study design involving semi-structured focus group discussions (FGDs) was conducted with 19 family medicine trainees in Malaysia. The conceptual framework used was based on the Theory of Planned Behavior. Thematic approach was used to analyze the data. Participants perceived FSD as being uncommon and unimportant. According to our participants, patients often presented with indirect complaints, and doctors were not proactive in asking about FSD. Three main barriers were identified: doctor factors, perceived patient factors, and system factors. Lack of confidence, knowledge, experience, time, and embarrassment were the key barriers identified at the doctors' level. Lack of awareness, among patients regarding FSD, and local cultural and religious norms were the perceived patient barriers. System barriers were lack of time and privacy. Various facilitators, such as continuous medical education and public forums, were suggested as means to encourage family medicine trainees to initiate discussion on sexual matters during consultations. In conclusion, family medicine trainees found it difficult to initiate conversation on FSD with patients. Interventions to encourage conversation on FSD should target this and other identified barriers.

Methamphetamine Cured my Cocaine Addiction

PubMed Central

Haile, Colin N.; De La Garza, Richard; Newton, Thomas F.

2011-01-01

Cocaine dependence is an enduring problem and years of research and drug development has yet to produce an efficacious pharmacotherapy. Recent clinical research suggests that chronic treatment with amphetamine-like medications produces tolerance to cocaine’s reinforcing effects and may offer a viable pharmacotherapy. Three methamphetamine-dependent participants that had been in our clinical laboratory experiments and previously addicted to cocaine are reviewed. Data obtained from initial screen and informal conversation suggested that all participants considered methamphetamine to have helped them stop using cocaine and eliminate cocaine craving. Methamphetamine also significantly decreased their alcohol consumption but did not alter cannabis or nicotine use. PMID:23066512

[Influence of childbirth experience and postpartum depression on quality of life in women after birth].

PubMed

Yeo, Jung Hee; Chun, Nami

2013-02-01

The purpose of this study was to identify influence of childbirth experience and postpartum depression on quality of life in women after birth. Two hundred and eleven postpartum women were asked to complete the questionnaires on their childbirth experience during their admission and on their postpartum depression and quality of life between one to three weeks after birth. Initial data were collected from February 1 to May 30, 2011 at two obstetric hospitals in Busan, Korea. Data were analyzed using t-test, ANOVA, Pearson correlation coefficients, and hierarchical multiple regression. The women's childbirth experience and postpartum depression were identified as factors influencing quality of life after birth. The model explained 50% of the variables. Results suggest that childbirth educators should include strategies to increase a positive childbirth experience and to decrease postpartum depression in their education programs in order to improve women's quality of life.

The Pulsed High Density Experiment (PHDX) Final Report

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

Slough, John P.; Andreason, Samuel

The purpose of this paper is to present the conclusions that can be drawn from the Field Reversed Configuration (FRC) formation experiments conducted on the Pulsed High Density experiment (PHD) at the University of Washington. The experiment is ongoing. The experimental goal for this first stage of PHD was to generate a stable, high flux (>10 mWb), high energy (>10 KJ) target FRC. Such results would be adequate as a starting point for several later experiments. This work focuses on experimental implementation and the results of the first four month run. Difficulties were encountered due to the initial on-axis plasmamore » ionization source. Flux trapping with this ionization source acting alone was insufficient to accomplish experimental objectives. Additional ionization methods were utilized to overcome this difficulty. A more ideal plasma source layout is suggested and will be explored during a forthcoming work.« less

Impaired acquisition of novel grapheme-color correspondences in synesthesia

PubMed Central

Brang, David; Ghiam, Michael; Ramachandran, Vilayanur S.

2013-01-01

Grapheme-color synesthesia is a neurological phenomenon in which letters and numbers (graphemes) consistently evoke particular colors (e.g., A may be experienced as red). These sensations are thought to arise through the cross-activation of grapheme processing regions in the fusiform gyrus and color area V4, supported by anatomical and functional imaging. However, the developmental onset of grapheme-color synesthesia remains elusive as research in this area has largely relied on self-report of these experiences in children. One possible account suggests that synesthesia is present at or near birth and initially binds basic shapes and forms to colors, which are later refined to grapheme-color associations through experience. Consistent with this view, studies show that similarly shaped letters and numbers tend to elicit similar colors in synesthesia and that some synesthetes consciously associate basic shapes with colors; research additionally suggests that synesthetic colors can emerge for newly learned characters with repeated presentation. This model further predicts that the initial shape-color correspondences in synesthesia may persist as implicit associations, driving the acquisition of colors for novel characters. To examine the presence of latent color associations for novel characters, synesthetes and controls were trained on pre-defined associations between colors and complex shapes, on the assumption that the prescribed shape-color correspondences would on average differ from implicit synesthetic associations. Results revealed synesthetes were less accurate than controls to learn novel shape-color associations, consistent with our suggestion that implicit form-color associations conflicted with the learned pairings. PMID:24198775

Impaired acquisition of novel grapheme-color correspondences in synesthesia.

PubMed

Brang, David; Ghiam, Michael; Ramachandran, Vilayanur S

2013-01-01

Grapheme-color synesthesia is a neurological phenomenon in which letters and numbers (graphemes) consistently evoke particular colors (e.g., A may be experienced as red). These sensations are thought to arise through the cross-activation of grapheme processing regions in the fusiform gyrus and color area V4, supported by anatomical and functional imaging. However, the developmental onset of grapheme-color synesthesia remains elusive as research in this area has largely relied on self-report of these experiences in children. One possible account suggests that synesthesia is present at or near birth and initially binds basic shapes and forms to colors, which are later refined to grapheme-color associations through experience. Consistent with this view, studies show that similarly shaped letters and numbers tend to elicit similar colors in synesthesia and that some synesthetes consciously associate basic shapes with colors; research additionally suggests that synesthetic colors can emerge for newly learned characters with repeated presentation. This model further predicts that the initial shape-color correspondences in synesthesia may persist as implicit associations, driving the acquisition of colors for novel characters. To examine the presence of latent color associations for novel characters, synesthetes and controls were trained on pre-defined associations between colors and complex shapes, on the assumption that the prescribed shape-color correspondences would on average differ from implicit synesthetic associations. Results revealed synesthetes were less accurate than controls to learn novel shape-color associations, consistent with our suggestion that implicit form-color associations conflicted with the learned pairings.

Coupled fluid and solid evolution in analogue volcanic vents

NASA Astrophysics Data System (ADS)

Solovitz, Stephen A.; Ogden, Darcy E.; Kim, Dave (Dae-Wook); Kim, Sang Young

2014-07-01

Volcanic eruptions emit rock particulates and gases at high speed and pressure, which change the shape of the surrounding rock. Simplified analytical solutions, field studies, and numerical models suggest that this process plays an important role in the behavior and hazards associated with explosive volcanic eruptions. Here we present results from a newly developed laboratory-scale apparatus designed to study this coupled process. The experiments used compressed air jets expanding into the laboratory through fabricated rock analogue material, which evolves through time during the experiment. The compressed air was injected at approximately 2.5 times atmospheric pressure. We fabricated rock analogues from sand and steel powder samples with a three-dimensional printing process. We studied the fluid development using phase-locked particle image velocimetry, while simultaneously observing the solid development via a video camera. We found that the fluid response was much more rapid than that of the solid, permitting a quasi-steady approximation. In most cases, the solid vent flared out rapidly, increasing its diameter by 20 to 100%. After the initial expansion, the vent and flow field achieved a near-steady condition for a long duration. The new expanded vent shapes permitted lower vent exit pressures and larger jet radii. In one experiment, after an initial vent shape development and establishment of steady flow behavior, rock failure occurred a second time, resulting in a new exit diameter and new steady state. This second failure was not precipitated by changes in the nozzle flow condition, and it radically changed the downstream flow dynamics. This experiment suggests that the brittle nature of volcanic host rock enables sudden vent expansion in the middle of an eruption without requiring a change in the conduit flow.

Beyond Reason: Emotion

NASA Astrophysics Data System (ADS)

Suárez Araujo, Carmen Paz; Barahona da Fonseca, Isabel; Barahona da Fonseca, José; Simões da Fonseca, J.

2004-08-01

A theoretical approach that aims to the identification of information processing that may be responsible for emotional dimensions of subjective experience is studied as an initial step in the construction of a neural net model of affective dimensions of psychological experiences. In this paper it is suggested that a way of orientated recombination of attributes can be present not only in the perceptive processing but also in cognitive ones. We will present an analysis of the most important emotion theories, we show their neural organization and we propose the neural computation approach as an appropriate framework for generating knowledge about the neural base of emotional experience. Finally, in this study we present a scheme corresponding to framework to design a computational neural multi-system for Emotion (CONEMSE).

Modeling Evolution of the Chandeleur Barrier Islands, Southeastern Louisiana: Initial Exploration of a Possible Threshold Crossing

NASA Astrophysics Data System (ADS)

Moore, L. J.; List, J. H.; Williams, S. J.

2007-12-01

Airborne photographic and lidar observations of the 72 km-long Chandeleur Island arc in southeastern Louisiana since August 2005 indicate that large volumes of sediment were removed from the islands during and following Hurricane Katrina and suggest that a return to pre-storm island configuration may be unlikely. Others have suggested, based on recent field observations, that the southern portion of the Chandeleur Islands may be showing signs of becoming an inner shelf shoal. In contrast to these observations, plentiful sand has been observed in the nearshore farther to the north; based on this finding it has been suggested that at least the northern portion of the Chandeleur Islands may be poised for recovery. Given the range of observations, it is unclear if Hurricane Katrina initiated a threshold crossing in the Chandeleurs causing the subaerial, landward- migrating barrier islands to begin evolving as submerged sand shoals. If a threshold crossing has not yet occurred and the Chandeleurs do recover from the impact of Hurricane Katrina, it remains uncertain how imminent a threshold crossing may be. To better understand the potential future evolution of the Chandeleur Islands and to assess the combination of factors that are likely to cause a threshold crossing in this environment, a series of initial model experiments are being conducted using the morphological-behavior model GEOMBEST. This model simulates the evolution of coastal morphology and stratigraphy resulting from changes in relative sea level and sediment supply, and provides insight into how barriers evolve over time scales ranging from decades to millennia. Vibracore logs, geophysical records, bathymetric surveys, and lidar surveys provide data necessary to design the model domain, while sediment budget studies, estimates of sea-level rise rates, and measurements of shoreline change rates provide input and calibration parameters. Late Holocene model runs simulate the evolution of 42 km-long North Chandeleur Island as it migrated from the distal end of the St. Bernard Delta to its modern position. Building on the late Holocene simulation, we present a series of initial, multi-decadal forward model experiments that assess the combination of factors, including relative sea-level rise rates, sediment supply rates, and geologic framework, that are likely to initiate a threshold crossing in the Chandeleur Islands.

Effects of Prior Experience on Shelter-Seeking Behavior of Juvenile American Lobsters.

PubMed

Bayer, Skylar R; Bianchi, Katherine M; Atema, Jelle; Jacobs, Molly W

2017-04-01

Shelter-seeking behaviors are vital for survival for a range of juvenile benthic organisms. These behaviors may be innate or they may be affected by prior experience. After hatching, American lobsters Homarus americanus likely first come into contact with shelter during the late postlarval (decapodid) stage, known as stage IV. After the subsequent molt to the first juvenile stage (stage V), they are entirely benthic and are thought to be highly cryptic. We hypothesized that postlarval (stage IV) experience with shelter would carry over into the first juvenile stage (stage V) and reduce the time needed for juveniles to locate and enter shelters (sheltering). We found some evidence of a carryover effect, but not the one we predicted: stage V juveniles with postlarval shelter experience took significantly longer to initiate sheltering. We also hypothesized that stage V juveniles would demonstrate learning by relocating shelters more quickly with immediate prior experience. Our findings were mixed. In a maze, juveniles with immediate prior experience were faster to regain visual contact with shelter, suggesting that they had learned the location of the shelter. In contrast, there was no significant effect of immediate prior experience on time to initiate sheltering in an open arena, or in the maze after juveniles had regained visual contact. We conclude that very young (stage V) juvenile lobsters modify their shelter-seeking behavior based on prior experiences across several timescales. Ecologically relevant variation in habitat exposure among postlarval and early juvenile lobsters may influence successful recruitment in this culturally and commercially important fishery species.

Factors influencing successful peer-reviewed publication of original research presentations from the American Society of Pediatric Otolaryngology (ASPO).

PubMed

MacKinney, Erin C; Chun, Robert H; Cassidy, Laura D; Link, T Roxanne; Sulman, Cecille G; Kerschner, Joseph E

2015-03-01

To analyze factors associated with progression of an original scientific presentation at the American Society of Pediatric Otolaryngology (ASPO) Annual Meeting to publication in a peer-reviewed journal. A dataset of presenters was created to enable prospective follow-up to assess early impressions regarding publication success with longer-term publication outcomes. Prior to the Annual ASPO meeting in 2013, a survey consisting of 10 questions was e-mailed to all 59 presenters. Questions were designed to assess presenter expectations on publication, barriers to publishing, and experience in presenting, publishing and clinical practice. A second survey was sent 12 months later to those respondents of the first survey who were amenable to follow-up. Overall, 46 of 59 (78%) presenters responded to the initial survey prior to their ASPO 2013 presentation. Of these, 34 agreed to participate in a longer-term follow-up of their presentation to publication experience. Of these 34, there were 17 who participated in the follow-up survey 1 year later. Just under half of the original respondents were residents (46%). All presenters (100%) planned to re-submit a revised manuscript if initially rejected. However, 35% of follow-up respondents did not make initial submission to a peer-reviewed journal. Results of a descriptive analysis suggest that more experienced researchers expect their submitted manuscript to be accepted for publication within a shorter time frame than those that have published fewer papers. Time was ranked as the greatest barrier to publication (60%) of those surveyed both in the initial prospective survey and for those who did not publish a paper in the follow-up survey (83%). This study suggests a strong desire and expectation of publishing ASPO presentations. Despite this expectation, past research and this data set suggest this expectation often does not materialize. "Time constraints" were the most commonly identified barrier to publication. To enhance dissemination of new findings from ASPO meetings, institutions and individuals should examine methods that facilitate and incentivize publication of findings in peer-reviewed publications. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Impact of individual clinical outcomes on trial participants' perspectives on enrollment in emergency research without consent.

PubMed

Whitesides, Louisa W; Baren, Jill M; Biros, Michelle H; Fleischman, Ross J; Govindarajan, Prasanthi R; Jones, Elizabeth B; Pancioli, Arthur M; Pentz, Rebecca D; Scicluna, Victoria M; Wright, David W; Dickert, Neal W

2017-04-01

Evidence suggests that patients are generally accepting of their enrollment in trials for emergency care conducted under exception from informed consent. It is unknown whether individuals with more severe initial injuries or worse clinical outcomes have different perspectives. Determining whether these differences exist may help to structure post-enrollment interactions. Primary clinical data from the Progesterone for the Treatment of Traumatic Brain Injury trial were matched to interview data from the Patients' Experiences in Emergency Research-Progesterone for the Treatment of Traumatic Brain Injury study. Answers to three key questions from Patients' Experiences in Emergency Research-Progesterone for the Treatment of Traumatic Brain Injury study were analyzed in the context of enrolled patients' initial injury severity (initial Glasgow Coma Scale and Injury Severity Score) and principal clinical outcomes (Extended Glasgow Outcome Scale and Extended Glasgow Outcome Scale relative to initial injury severity). The three key questions from Patients' Experiences in Emergency Research-Progesterone for the Treatment of Traumatic Brain Injury study addressed participants' general attitude toward inclusion in the Progesterone for the Treatment of Traumatic Brain Injury trial (general trial inclusion), their specific attitude toward being included in Progesterone for the Treatment of Traumatic Brain Injury trial under the exception from informed consent (personal exception from informed consent enrollment), and their attitude toward the use of exception from informed consent in the Progesterone for the Treatment of Traumatic Brain Injury trial in general (general exception from informed consent enrollment). Qualitative analysis of interview transcripts was performed to provide contextualization and to determine the extent to which respondents framed their attitudes in terms of clinical experience. Clinical data from Progesterone for the Treatment of Traumatic Brain Injury trial were available for all 74 patients represented in the Patients' Experiences in Emergency Research-Progesterone for the Treatment of Traumatic Brain Injury study (including 46 patients for whom the surrogate was interviewed due to the patient's cognitive status or death). No significant difference was observed regarding acceptance of general trial inclusion or acceptance of general exception from informed consent enrollment between participants with favorable neurological outcomes and those with unfavorable outcomes relative to initial injury. Agreement with personal enrollment in Progesterone for the Treatment of Traumatic Brain Injury trial under exception from informed consent, however, was significantly higher among participants with favorable outcomes compared to those with unfavorable outcomes (89% vs 59%, p = 0.003). There was also a statistically significant relationship between more severe initial injury and increased acceptance of personal exception from informed consent enrollment ( p = 0.040) or general exception from informed consent use ( p = 0.034) in Progesterone for the Treatment of Traumatic Brain Injury trial. Many individuals referenced personal experience as a basis for their attitudes, but these references were not used to support negative views. Patients and surrogates of patients with unfavorable clinical outcomes were somewhat less accepting of their own inclusion in the Progesterone for the Treatment of Traumatic Brain Injury trial under exception from informed consent than were patients or surrogates of patients with favorable clinical outcomes. These findings suggest a need to identify optimal strategies for communicating with patients and their surrogates regarding exception from informed consent enrollment when clinical outcomes are poor.

Swapping Horses Midstream: Factors Related to Physicians’ Changing Their Minds About a Diagnosis

PubMed Central

Eva, Kevin W.; Link, Carol L.; Lutfey, Karen E.; McKinlay, John B.

2013-01-01

Purpose Premature closure has been identified as the single most common cause of diagnostic error. The authors conducted a factorial experiment to explore which variables exert an unconfounded influence on physicians’ diagnostic flexibility (changing their minds about the most likely diagnosis during a clinical case presentation). Methods In 2007–2008, 256 practicing physicians viewed a clinically authentic vignette simulating a patient presenting with possible coronary heart disease (CHD), provided their initial impression midway through the case, answered questions about the case, indicated how they would continue their clinical investigation, and made a final diagnosis. The authors used general linear models to determine which patient factors (age, gender, socioeconomic status, race), physician factors (gender, age/experience), and process variables were related to the likelihood of physicians’ changing their minds about the most likely diagnosis. Results Physicians who had less experience, those who named a non-CHD diagnosis as their initial impression, and those who did not ask for information about the patient’s prior cardiac disease history were the most likely to change their minds. Participants’ certainty in their initial diagnosis, the additional information desired, the diagnostic hypotheses generated, and the follow-up intended were not related to the likelihood of change in diagnostic hypotheses. Discussion While efforts encouraging physicians to avoid cognitive biases and to reason in a more analytic manner may yield some benefit, this study suggests that experience is a more important determinant of diagnostic flexibility than is the consideration of additional diagnoses or the amount of additional information collected. PMID:20592506

Iconic memory requires attention

PubMed Central

Persuh, Marjan; Genzer, Boris; Melara, Robert D.

2012-01-01

Two experiments investigated whether attention plays a role in iconic memory, employing either a change detection paradigm (Experiment 1) or a partial-report paradigm (Experiment 2). In each experiment, attention was taxed during initial display presentation, focusing the manipulation on consolidation of information into iconic memory, prior to transfer into working memory. Observers were able to maintain high levels of performance (accuracy of change detection or categorization) even when concurrently performing an easy visual search task (low load). However, when the concurrent search was made difficult (high load), observers' performance dropped to almost chance levels, while search accuracy held at single-task levels. The effects of attentional load remained the same across paradigms. The results suggest that, without attention, participants consolidate in iconic memory only gross representations of the visual scene, information too impoverished for successful detection of perceptual change or categorization of features. PMID:22586389

Iconic memory requires attention.

PubMed

Persuh, Marjan; Genzer, Boris; Melara, Robert D

2012-01-01

Two experiments investigated whether attention plays a role in iconic memory, employing either a change detection paradigm (Experiment 1) or a partial-report paradigm (Experiment 2). In each experiment, attention was taxed during initial display presentation, focusing the manipulation on consolidation of information into iconic memory, prior to transfer into working memory. Observers were able to maintain high levels of performance (accuracy of change detection or categorization) even when concurrently performing an easy visual search task (low load). However, when the concurrent search was made difficult (high load), observers' performance dropped to almost chance levels, while search accuracy held at single-task levels. The effects of attentional load remained the same across paradigms. The results suggest that, without attention, participants consolidate in iconic memory only gross representations of the visual scene, information too impoverished for successful detection of perceptual change or categorization of features.

Population cage experiments with a vertebrate: The temporal demography and cytonuclear genetics of hybridization on Gambusia fishes

USGS Publications Warehouse

Scribner, Kim T.; Avise, John C.

1994-01-01

The dynamics of mitochondrial and multilocus nuclear genotypic frequencies were monitored for 2 yr in experimental populations established with equal numbers of two poeciliid fishes (Gambusia affinis and Gambusia holbrooki) that hybridize naturally in the southeastern United States. In replicated "small-pool" populations (experiment I), 1018 sampled individuals at six time periods revealed an initial flush of hybridization, followed by a rapid decline in frequencies of G. affinis nuclear and mitochondrial alleles over 64 wk. Decay of gametic and cytonuclear disequilibria differed from expectations under random mating as well as under a model of assortative mating involving empirically estimated mating propensities. In two replicate "large-pond" populations (experiment II), 841 sampled individuals across four reproductive cohorts revealed lower initial frequencies of F1 hybrids than in experiment I, but again G. holbrooki alleles achieved high frequencies over four generations (72 wk). Thus, evolution within experimental Gambusia hybrid populations can be extremely rapid, resulting in consistent loss of G. affinis nuclear and cytoplasmic alleles. Concordance in results between experiments and across genetic markers suggests strong directional selection favoring G. holbrooki genotypes. Results are interpreted in light of previous reports of genotype-specific differences in life-history traits, reproductive ecology, patterns of recruitment, and size-specific mortality, and in the context of patterns of introgression previously studied indirectly from spatial observations on cytonuclear genotypes in natural Gambusia populations.

The Play Experience Scale: development and validation of a measure of play.

PubMed

Pavlas, Davin; Jentsch, Florian; Salas, Eduardo; Fiore, Stephen M; Sims, Valerie

2012-04-01

A measure of play experience in video games was developed through literature review and two empirical validation studies. Despite the considerable attention given to games in the behavioral sciences, play experience remains empirically underexamined. One reason for this gap is the absence of a scale that measures play experience. In Study 1, the initial Play Experience Scale (PES) was tested through an online validation that featured three different games (N = 203). In Study 2, a revised PES was assessed with a serious game in the laboratory (N = 77). Through principal component analysis of the Study 1 data, the initial 20-item PES was revised, resulting in the 16-item PES-16. Study 2 showed the PES-16 to be a robust instrument with the same patterns of correlations as in Study 1 via (a) internal consistency estimates, (b) correlations with established scales of motivation, (c) distributions of PES-16 scores in different game conditions, and (d) examination of the average variance extracted of the PES and the Intrinsic Motivation Scale. We suggest that the PES is appropriate for use in further validation studies. Additional examinations of the scale are required to determine its applicability to other contexts and its relationship with other constructs. The PES is potentially relevant to human factors undertakings involving video games, including basic research into play, games, and learning; prototype testing; and exploratory learning studies.

Suicide and war: the mediating effects of negative mood, posttraumatic stress disorder symptoms, and social support among army National Guard soldiers.

PubMed

Griffith, James

2012-08-01

The mediating effects of posttraumatic stress disorder (PTSD) symptoms, negative mood, and social support on the relationship of war experiences to suicidality were examined. The research literature suggested a sequence among study scales representing these constructs, which was then tested on survey data obtained from a sample of National Guard soldiers (N=4,546). Results from structural equation modeling suggested that war experiences may precipitate a sequence of psychological consequences leading to suicidality. However, suicidality may be an enduring behavioral health condition. War experiences showed no direct effects on postdeployment suicidality, rather its effect was indirect through PTSD symptoms and negative mood. War experiences were, however, predictive of PTSD symptoms, as would be expected. PSTD symptoms showed no direct effect on postdeployment suicidality, but showed indirect effects through negative mood. Results also suggested that suicidality is relatively persistent, at least during deployment and postdeployment. The percentage of those at risk for suicide was low both during and after deployment, with little association between suicidality and time since returning from deployment. Additionally, few soldiers were initially nonsuicidal and then reported such symptoms at postdeployment. Implications of relationships of both negative mood and combat trauma to suicidality are discussed, as well as possible mediating effects of both personal dispositions and social support on relationships of war experiences to PTSD, negative mood, and suicidality. © 2012 The American Association of Suicidology.

Here Today, Gone Tomorrow – Adaptation to Change in Memory-Guided Visual Search

PubMed Central

Zellin, Martina; Conci, Markus; von Mühlenen, Adrian; Müller, Hermann J.

2013-01-01

Visual search for a target object can be facilitated by the repeated presentation of an invariant configuration of nontargets (‘contextual cueing’). Here, we tested adaptation of learned contextual associations after a sudden, but permanent, relocation of the target. After an initial learning phase targets were relocated within their invariant contexts and repeatedly presented at new locations, before they returned to the initial locations. Contextual cueing for relocated targets was neither observed after numerous presentations nor after insertion of an overnight break. Further experiments investigated whether learning of additional, previously unseen context-target configurations is comparable to adaptation of existing contextual associations to change. In contrast to the lack of adaptation to changed target locations, contextual cueing developed for additional invariant configurations under identical training conditions. Moreover, across all experiments, presenting relocated targets or additional contexts did not interfere with contextual cueing of initially learned invariant configurations. Overall, the adaptation of contextual memory to changed target locations was severely constrained and unsuccessful in comparison to learning of an additional set of contexts, which suggests that contextual cueing facilitates search for only one repeated target location. PMID:23555038

Evidence for an early wet Moon from experimental crystallization of the lunar magma ocean

NASA Astrophysics Data System (ADS)

Lin, Yanhao; Tronche, Elodie J.; Steenstra, Edgar S.; van Westrenen, Wim

2017-01-01

The Moon is thought to have been covered initially by a deep magma ocean, its gradual solidification leading to the formation of the plagioclase-rich highland crust. We performed a high-pressure, high-temperature experimental study of lunar mineralogical and geochemical evolution during magma ocean solidification that yields constraints on the presence of water in the earliest lunar interior. In the experiments, a deep layer containing both olivine and pyroxene is formed in the first ~50% of crystallization, β-quartz forms towards the end of crystallization, and the last per cent of magma remaining is extremely iron rich. In dry experiments, plagioclase appears after 68 vol.% solidification and yields a floatation crust with a thickness of ~68 km, far above the observed average of 34-43 km based on lunar gravity. The volume of plagioclase formed during crystallization is significantly less in water-bearing experiments. Using the relationship between magma water content and the resulting crustal thickness in the experiments, and considering uncertainties in initial lunar magma ocean depth, we estimate that the Moon may have contained at least 270 to 1,650 ppm water at the time of magma ocean crystallization, suggesting the Earth-Moon system was water-rich from the start.

Sports participation, age at smoking initiation, and the risk of smoking among US high school students.

PubMed

Escobedo, L G; Marcus, S E; Holtzman, D; Giovino, G A

1993-03-17

To examine smoking patterns, smoking initiation, and the relationship of sports participation and age at smoking initiation to regular and heavy smoking among adolescents. Survey. A nationally representative sample of US high school students. Prevalences of smoking patterns, prevalence and incidence of smoking initiation, and prevalences and odds of regular and heavy smoking in relation to sports participation and age at smoking initiation. Seventy-two percent of students reported experimenting with, formerly, or ever smoking cigarettes, and 32% reported smoking in the past 30 days. Students who had participated in interscholastic sports were less likely to be regular and heavy smokers than were others who had not participated. Smoking initiation rates increased rapidly after age 10 years and peaked at age 13 to 14 years. Students who began smoking at age 12 years or younger were more likely to be regular and heavy smokers than were students who began smoking at older ages. These data suggest that smoking initiation at a young age can increase the risk of nicotine addiction during adolescence and that sports participation may influence smoking behavior. Interventions to prevent smoking should be available before age 12 years to help combat the smoking epidemic among youth.

Concatenation of Observed Grasp Phases with Observer’s Distal Movements: A Behavioural and TMS Study

PubMed Central

De Stefani, Elisa; Innocenti, Alessandro; De Marco, Doriana; Gentilucci, Maurizio

2013-01-01

The present study aimed at determining how actions executed by two conspecifics can be coordinated with each other, or more specifically, how the observation of different phases of a reaching-grasping action is temporary related to the execution of a movement of the observer. Participants observed postures of initial finger opening, maximal finger aperture, and final finger closing of grasp after observation of an initial hand posture. Then, they opened or closed their right thumb and index finger (experiments 1, 2 and 3). Response times decreased, whereas acceleration and velocity of actual finger movements increased when observing the two late phases of grasp. In addition, the results ruled out the possibility that this effect was due to salience of the visual stimulus when the hand was close to the target and confirmed an effect of even hand postures in addition to hand apparent motion due to the succession of initial hand posture and grasp phase. In experiments 4 and 5, the observation of grasp phases modulated even foot movements and pronunciation of syllables. Finally, in experiment 6, transcranial magnetic stimulation applied to primary motor cortex 300 ms post-stimulus induced an increase in hand motor evoked potentials of opponens pollicis muscle when observing the two late phases of grasp. These data suggest that the observation of grasp phases induced simulation which was stronger during observation of finger closing. This produced shorter response times, greater acceleration and velocity of the successive movement. In general, our data suggest best concatenation between two movements (one observed and the other executed) when the observed (and simulated) movement was to be accomplished. The mechanism joining the observation of a conspecific’s action with our own movement may be precursor of social functions. It may be at the basis for interactions between conspecifics, and related to communication between individuals. PMID:24278395

The role of first impression in operant learning.

PubMed

Shteingart, Hanan; Neiman, Tal; Loewenstein, Yonatan

2013-05-01

We quantified the effect of first experience on behavior in operant learning and studied its underlying computational principles. To that goal, we analyzed more than 200,000 choices in a repeated-choice experiment. We found that the outcome of the first experience has a substantial and lasting effect on participants' subsequent behavior, which we term outcome primacy. We found that this outcome primacy can account for much of the underweighting of rare events, where participants apparently underestimate small probabilities. We modeled behavior in this task using a standard, model-free reinforcement learning algorithm. In this model, the values of the different actions are learned over time and are used to determine the next action according to a predefined action-selection rule. We used a novel nonparametric method to characterize this action-selection rule and showed that the substantial effect of first experience on behavior is consistent with the reinforcement learning model if we assume that the outcome of first experience resets the values of the experienced actions, but not if we assume arbitrary initial conditions. Moreover, the predictive power of our resetting model outperforms previously published models regarding the aggregate choice behavior. These findings suggest that first experience has a disproportionately large effect on subsequent actions, similar to primacy effects in other fields of cognitive psychology. The mechanism of resetting of the initial conditions that underlies outcome primacy may thus also account for other forms of primacy. PsycINFO Database Record (c) 2013 APA, all rights reserved.

Evaluating the contributions of task expectancy in the testing and guessing benefits on recognition memory.

PubMed

Huff, Mark J; Yates, Tyler J; Balota, David A

2018-05-03

Recently, we have shown that two types of initial testing (recall of a list or guessing of critical items repeated over 12 study/test cycles) improved final recognition of related and unrelated word lists relative to restudy. These benefits were eliminated, however, when test instructions were manipulated within subjects and presented after study of each list, procedures designed to minimise expectancy of a specific type of upcoming test [Huff, Balota, & Hutchison, 2016. The costs and benefits of testing and guessing on recognition memory. Journal of Experimental Psychology: Learning, Memory, and Cognition, 42, 1559-1572. doi: 10.1037/xlm0000269 ], suggesting that testing and guessing effects may be influenced by encoding strategies specific for the type of upcoming task. We follow-up these experiments by examining test-expectancy processes in guessing and testing. Testing and guessing benefits over restudy were not found when test instructions were presented either after (Experiment 1) or before (Experiment 2) a single study/task cycle was completed, nor were benefits found when instructions were presented before study/task cycles and the task was repeated three times (Experiment 3). Testing and guessing benefits emerged only when instructions were presented before a study/task cycle and the task was repeated six times (Experiments 4A and 4B). These experiments demonstrate that initial testing and guessing can produce memory benefits in recognition, but only following substantial task repetitions which likely promote task-expectancy processes.

Cognitive reappraisal increases neuroendocrine reactivity to acute social stress and physical pain.

PubMed

Denson, Thomas F; Creswell, J David; Terides, Matthew D; Blundell, Kate

2014-11-01

Cognitive reappraisal can foster emotion regulation, yet less is known about whether cognitive reappraisal alters neuroendocrine stress reactivity. Some initial evidence suggests that although long-term training in cognitive behavioral therapy techniques (which include reappraisal as a primary training component) can reduce cortisol reactivity to stress, some studies also suggest that reappraisal is associated with heightened cortisol stress reactivity. To address this mixed evidence, the present report describes two experimental studies that randomly assigned young adult volunteers to use cognitive reappraisal while undergoing laboratory stressors. Relative to the control condition, participants in the reappraisal conditions showed greater peak cortisol reactivity in response to a socially evaluative speech task (Experiment 1, N=90) and to a physical pain cold pressor task (Experiment 2, N=94). Participants in the cognitive reappraisal group also reported enhanced anticipatory psychological appraisals of self-efficacy and control in Experiment 2 and greater post-stressor self-efficacy. There were no effects of the reappraisal manipulation on positive and negative subjective affect, pain, or heart rate in either experiment. These findings suggest that although cognitive reappraisal fosters psychological perceptions of self-efficacy and control under stress, this effortful emotion regulation strategy in the short-term may increase cortisol reactivity. Discussion focuses on promising psychological mechanisms for these cognitive reappraisal effects. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

The use of nicotinic acid to induce sustained low plasma nonesterified fatty acids in feed-restricted Holstein cows.

PubMed

Pires, J A A; Grummer, R R

2007-08-01

The objectives were to determine the effects of nicotinic acid (NA) on blood metabolites (experiment 1) and whether successive doses of NA could induce sustained reductions of plasma nonesterified fatty acids (NEFA; experiment 2) in feed-restricted, nonlactating Holstein cows. Experiment 1 was a single 4 x 4 Latin square with 1-wk periods. Each period consisted of 2.5 d of feed restriction to increase plasma NEFA and 4.5 d of ad libitum feeding. Treatments were abomasal administration of 0, 6, 30, or 60 mg of NA/kg of body weight (BW), given as a single bolus 48 h after initiation of feed restriction. Plasma NEFA concentration decreased from 546 microEq/L to 208 +/- 141 microEq/L at 1 h after the infusion of 6 mg of NA/kg of BW, and to less than 100 +/- 148 microEq/L at 3 h after the abomasal infusion of the 2 highest doses of NA. A rebound occurred after the initial decrease of plasma NEFA concentration. The rebound lasted up to 9 h for the 30-mg dose of NA, and up to 6 h for the 6-mg dose. Experiment 2 was a randomized complete block design with 3 treatments and 6 cows. Starting at 48 h of feed restriction, cows received 9 hourly abomasal infusions of 0, 6, or 10 mg of NA/kg of BW. Plasma NEFA concentrations decreased from 553 microEq/L +/- 24 immediately before the initiation of treatments to <100 microEq/L during hourly infusions of 6 or 10 mg of NA/kg. Data suggest that the maximal antilipolytic response was achieved with the lowest dose of NA. A rebound of NEFA started 2 to 3 h after NA infusions were terminated. In both experiments, the NEFA rebound period coincided with increases in insulin and no change or increased glucose concentrations, suggesting a state of insulin resistance induced by elevated NEFA. This model for reducing plasma NEFA concentration by abomasal infusions of NA can be used to study the metabolic ramifications of elevated vs. reduced NEFA concentrations. The data demonstrate potential benefits and pitfalls of using NA to regulate plasma NEFA and prevent lipid-related metabolic disorders.

The measurement of hemoglobin oxygen saturation using multiwavelength photoacoustic microscopy

NASA Astrophysics Data System (ADS)

Deng, Zilin; Yang, Xiaoquan; Yu, Lejun; Gong, Hui

2010-02-01

Hemoglobin oxygen saturation (SO2) is one of the most critical functional parameters to the metabolism. In this paper, we mainly introduced some initial results of measuring blood oxygen using multi-wavelength photoacoustic microscopy (PAM). In phantom study, we demonstrate the photoacoustic signal amplitude increases linearly with the concentration of red or blue ink. Then the calculated concentration of red ink in double-ink mixtures with PAM has a 5% difference with the result measured with spectrophotometric analysis. In ex vivo experiment, the measured result exhibt 15% difference between the PAM and spectrophotometric analysis. Experiment results suggest that PAM could be used to determine the SO2 quantitatively.

The vestibulo-ocular reflex and its possible roles in space motion sickness

NASA Technical Reports Server (NTRS)

Watt, Douglas G. D.

1987-01-01

Prolonged exposure to an inappropriate vestibulo-ocular reflex (VOR) will usually lead to motion sickness, and it has been predicted on theoretical grounds that VOR gain may be decreased in weightlessness. While experiments during parabolic flight in aircraft tend to confirm this prediction, experiments during orbital spaceflight have led to apparently contradictory results. It is suggested that VOR gain is reduced initially, but that rapid compensatory mechanisms restore it to normal within minutes of reaching weightlessness. However, even though this process may lead to the rapid return of functionally normal gaze stability, it may not protect against the development of motion sickness.

Not all Anchors Weigh Equally.

PubMed

Greenstein, Michael; Velazquez, Alexandra

2017-11-01

The anchoring bias is a reliable effect wherein a person's judgments are affected by initially presented information, but it is unknown specifically why this effect occurs. Research examining this bias suggests that elements of both numeric and semantic priming may be involved. To examine this, the present research used a phenomenon wherein people treat numeric information presented differently in Arabic numeral or verbal formats. We presented participants with one of many forms of an anchor that represented the same value (e.g., twelve hundred or 1,200). Thus, we could examine how a concept's meaning and its absolute numeric value affect anchoring. Experiments 1 and 2 showed that people respond to Arabic and verbal anchors differently. Experiment 3 showed that these differences occurred largely because people tend to think of numbers in digit format. This suggests that one's conceptual understanding of the anchored information matters more than its strict numeric value.

Executive function predicts artificial language learning

PubMed Central

Kapa, Leah L.; Colombo, John

2017-01-01

Previous research suggests executive function (EF) advantages among bilinguals compared to monolingual peers, and these advantages are generally attributed to experience controlling two linguistic systems. However, the possibility that the relationship between bilingualism and EF might be bidirectional has not been widely considered; while experience with two languages might improve EF, better EF skills might also facilitate language learning. In the current studies, we tested whether adults’ and preschool children’s EF abilities predicted success in learning a novel artificial language. After controlling for working memory and English receptive vocabulary, adults’ artificial language performance was predicted by their inhibitory control ability (Study 1) and children’s performance was predicted by their attentional monitoring and shifting ability (Study 2). These findings provide preliminary evidence suggesting that EF processes may be employed during initial stages of language learning, particularly vocabulary acquisition, and support the possibility of a bidirectional relationship between EF and language acquisition. PMID:29129958

Semantic effects in naming perceptual identification but not in delayed naming: implications for models and tasks.

PubMed

Wurm, Lee H; Seaman, Sean R

2008-03-01

Previous research has demonstrated that the subjective danger and usefulness of words affect lexical decision times. Usually, an interaction is found: Increasing danger predicts faster reaction times (RTs) for words low on usefulness, but increasing danger predicts slower RTs for words high on usefulness. The authors show the same interaction with immediate auditory naming. The interaction disappeared with a delayed auditory naming control experiment, suggesting that it has a perceptual basis. In an attempt to separate input (signal to ear) from output (brain to muscle) processes in word recognition, the authors ran 2 auditory perceptual identification experiments. The interaction was again significant, but performance was best for words high on both danger and usefulness. This suggests that initial demonstrations of the interaction were reflecting an output approach/withdraw response conflict induced by stimuli that are both dangerous and useful. The interaction cannot be characterized as a tradeoff of speed versus accuracy.

Vertical interventions and system effects; have we learned anything from past experiences?

PubMed Central

Oliveira, Charlotte; Russo, Giuliano

2015-01-01

The recent Ebola Virus Outbreak had a devastating effect on West Africa's already feeble national health systems. We suggest that such an impact turned out to be catastrophic because it hit particularly hard human resources for health and the delivery of primary healthcare services, which are cross-sectional to any health system. National and international interventions failed to understand the nature of this interaction, and concentrated on attending urgent specific vertical functions to fight the outbreak - the pillars - such as surveillance, logistics, safe burials etc. Such patchwork and vertical intervention strategy was always going to fail to tackle a system-wide problem, particularly in already fragile systems. We suggest that future interventions will have to learn from the experience of past initiatives for the introduction of HIV-AIDS services, which started as vertical programs and ended up including ever growing health system strengthening components. PMID:26523197

Hugoniots of aerogels involving carbon and resorcinol formaldehyde

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

Hrubesh, L H; Ree, F H; Schmidt, R D

1999-06-24

Recently, a first-order phase transition is predicted in liquid carbon using atomistic simulation and Brenner's bond order potential. There are also experimental data suggesting a possibility for a first-order phase transition. In light of this, a thermochemical equilibrium code (CHEQ) is used to provide guidance to experiments to find a liquid-liquid phase change in carbon foam and carbon-rich aerogel, resorcinol formaldehyde. Isotherms and Hugoniots were computed based on the previous analysis by van Thiel and Ree. The present calculations predict the liquid-liquid-graphite triple point to be at 5000 K and 5.2 GPa and its critical point to be at 6000more » K and 8.8 GPa. The present Hugoniot calculations suggest that the liquid-liquid phase transition may be detected by performing a shock experiment with initial density of approximately 0.15 gm/cm{sup 3}.« less

An Analysis of the Time Course of Lexical Processing During Reading

PubMed Central

Sheridan, Heather; Reichle, Erik D.

2016-01-01

Reingold, Reichle, Glaholt, and Sheridan (2012) reported a gaze-contingent eye-movement experiment in which survival-curve analyses were used to examine the effects of word frequency, the availability of parafoveal preview, and initial fixation location on the time course of lexical processing. The key results of these analyses suggest that lexical processing begins very rapidly (after approximately 120 ms), and is supported by substantial parafoveal processing (more than 100 ms). Because it is not immediately obvious that these results are congruent with the theoretical assumption that words are processed and identified in a strictly serial manner, we attempted to simulate the experiment using the E-Z Reader model of eye-movement control (Reichle, 2011). These simulations were largely consistent with the empirical results, suggesting that parafoveal processing does play an important functional role by allowing lexical processing to occur rapidly enough to mediate direct control over when the eyes move during reading. PMID:25939443

Experimental postseismic recovery of fractured rocks assisted by calcite sealing

NASA Astrophysics Data System (ADS)

Aben, F. M.; Doan, M.-L.; Gratier, J.-P.; Renard, F.

2017-07-01

Postseismic recovery within fault damage zones involves slow healing of coseismic fractures leading to permeability reduction and strength increase with time. To better understand this process, experiments were performed by long-term fluid percolation with calcite precipitation through predamaged quartz-monzonite samples subjected to upper crustal conditions of stress and temperature. This resulted in a P wave velocity recovery of 50% of its initial drop after 64 days. In contrast, the permeability remained more or less constant for the duration of the experiment. Microstructures, fluid chemistry, and X-ray microtomography demonstrate that incipient calcite sealing and asperity dissolution are responsible for the P wave velocity recovery. The permeability is unaffected because calcite precipitates outside of the main flow channels. The highly nonparallel evolution of strength recovery and permeability suggests that fluid conduits within fault damage zones can remain open fluid conduits after an earthquake for much longer durations than suggested by the seismic monitoring of fault healing.

The locus of word frequency effects in skilled spelling-to-dictation.

PubMed

Chua, Shi Min; Liow, Susan J Rickard

2014-01-01

In spelling-to-dictation tasks, skilled spellers consistently initiate spelling of high-frequency words faster than that of low-frequency words. Tainturier and Rapp's model of spelling shows three possible loci for this frequency effect: spoken word recognition, orthographic retrieval, and response execution of the first letter. Thus far, researchers have attributed the effect solely to orthographic retrieval without considering spoken word recognition or response execution. To investigate word frequency effects at each of these three loci, Experiment 1 involved a delayed spelling-to-dictation task and Experiment 2 involved a delayed/uncertain task. In Experiment 1, no frequency effect was found in the 1200-ms delayed condition, suggesting that response execution is not affected by word frequency. In Experiment 2, no frequency effect was found in the delayed/uncertain task that reflects the orthographic retrieval, whereas a frequency effect was found in the comparison immediate/uncertain task that reflects both spoken word recognition and orthographic retrieval. The results of this two-part study suggest that frequency effects in spoken word recognition play a substantial role in skilled spelling-to-dictation. Discrepancies between these findings and previous research, and the limitations of the present study, are discussed.

Patient's experience with comorbidity management in primary care: a qualitative study of comorbid pain and obesity.

PubMed

Janke, E Amy; Ramirez, Michelle L; Haltzman, Brittany; Fritz, Megan; Kozak, Andrea T

2016-01-01

The aim of this research is to examine perceptions of those with comorbid chronic pain and obesity regarding their experience of comorbidity management in primary care settings. Chronic pain and obesity are common comorbidities frequently managed in primary care settings. Evidence suggests individuals with this comorbidity may be at risk for suboptimal clinical interactions; however, treatment experiences and preferences of those with comorbid chronic pain and obesity have received little attention. Semi-structured interviews conducted with 30 primary care patients with mean body mass index=36.8 and comorbid persistent pain. The constant comparative method was used to analyze data. Participants discussed frustration with a perceived lack of information tailored to their needs and a desire for a personalized treatment experience. Participants found available medical approaches unsatisfying and sought a more holistic approach to management. Discussions also focused around the need for providers to initiate efforts at education and motivation enhancement and to show concern for and understanding of the unique difficulties associated with comorbidity. Findings suggest providers should engage in integrated communication regarding weight and pain, targeting this multimorbidity using methods aligned with priorities discussed by patients.

When a Picasso is a "Picasso": the entry point in the identification of visual art.

PubMed

Belke, B; Leder, H; Harsanyi, G; Carbon, C C

2010-02-01

We investigated whether art is distinguished from other real world objects in human cognition, in that art allows for a special memorial representation and identification based on artists' specific stylistic appearances. Testing art-experienced viewers, converging empirical evidence from three experiments, which have proved sensitive to addressing the question of initial object recognition, suggest that identification of visual art is at the subordinate level of the producing artist. Specifically, in a free naming task it was found that art-objects as opposed to non-art-objects were most frequently named with subordinate level categories, with the artist's name as the most frequent category (Experiment 1). In a category-verification task (Experiment 2), art-objects were recognized faster than non-art-objects on the subordinate level with the artist's name. In a conceptual priming task, subordinate primes of artists' names facilitated matching responses to art-objects but subordinate primes did not facilitate responses to non-art-objects (Experiment 3). Collectively, these results suggest that the artist's name has a special status in the memorial representation of visual art and serves as a predominant entry point in recognition in art perception. Copyright 2009 Elsevier B.V. All rights reserved.

Logjam Deformation: Experimental analogs with variable flow

NASA Astrophysics Data System (ADS)

Deshpande, N.; Crosby, B. T.

2017-12-01

Observed deformation of a massive, channel-spanning logjam in Big Creek, Idaho inspired a suite of physical experiments exploring logjam kinematics in a simplified but controlled setting. Using chopsticks as surrogates for logs, we conducted experiments in a 6 m long and 1.22 m wide channel with a semi-circular, textured bed. Nails driven into the bed restrain the chopsticks and initialize logjam formation. We conducted 24 hour experiments hours under two discharge conditions: (A) constant base discharge and (B) alternating discharge between the base flow and a doubled flow. After initial stabilization, we use high-resolution down-looking photographs at one-minute intervals to construct time-lapse videos and for Particle Image Velocimetry. Despite identical experimental protocols during stabilization, the starting configuration of chopsticks is markedly different for each run. In Experiment A, the orientations and packing of chopsticks is visibly less ordered than Experiment B. However, deformation in both experiments is accomplished by the same three mechanisms: rigid blocks that propagate downstream as v-shaped fronts bounded by shear planes, logjam-wide adjustments in response to the change in position of a key member, and independent logs whose trajectories either travel underneath the logjam or adjust unbounded in the backwater. Total compression is 46% and 80% for experiment A and B, respectively. Time-series of incremental displacements for both experiments decrease noisily over time, but zero displacement is never reached. Despite very different hydrologic forcings, cumulative rates of deformation for both experiments are similar, suggesting that the progressive deformation of disordered, elongate particles (chopsticks and logs) within a larger ensemble leads to denser packing, and that this mechanism best describes logjam deformation.

[Review of transgenic crop breeding in China].

PubMed

Huang, Dafang

2015-06-01

The development history and fundamental experience of transgenic crops (Genetically modified crops) breeding in China for near 30 years were reviewed. It was illustrated that a scientific research, development and industrialization system of transgenic crops including gene discovery, transformation, variety breeding, commercialization, application and biosafety assessment has been initially established which was few in number in the world. The research innovative capacity of transgenic cotton, rice and corn has been lifted. The research features as well as relative advantages have been initially formed. The problems and challenges of transgenic crop development were discussed. In addition, three suggestions of promoting commercialization, speeding up implementation of the Major National Project of GM Crops, and enhancing science communication were made.

Police-Related Experiences and HIV Risk Among Female Sex Workers in Andhra Pradesh, India

PubMed Central

Reed, Elizabeth; Blankenship, Kim M.

2011-01-01

Research suggests experiences with police are related to human immunodeficiency virus (HIV) sexual risk among women working as sex workers. However, little is known about the links between specific police-related behaviors and HIV vulnerability. We examine whether 5 police-related experiences are associated with measures of HIV risk and violence among a sample of female sex workers (FSWs) in Andhra Pradesh, India, and consider the implications for HIV prevention. FSWs at least 18 years of age (n = 835) were recruited through respondent-driven sampling for a cross-sectional survey conducted as part of Avahan, the India AIDS Initiative. Using logistic regression models adjusted for age, age at start of sex work, and sex work venue, we assessed police-related experiences reported by FSWs in relation to HIV risk behaviors and violence. Results showed having sex with police to avoid trouble, giving gifts to police to avoid trouble, having police take condoms away, experiencing a workplace raid, and being arrested were associated with sexually transmitted infection symptoms, inconsistent condom use, acceptance of more money for sex without a condom, and experience of client violence. These findings suggest a need for interventions targeting police–FSW interactions to reduce HIV vulnerability among FSWs. PMID:22043036

Hardness, function, emotional well-being, satisfaction and the overall sexual experience in men using 100-mg fixed-dose or flexible-dose sildenafil citrate

PubMed Central

Ströberg, P; Kaminetsky, J C; Park, N C; Goldfischer, E R; Creanga, D L; Stecher, V J

2010-01-01

The prescribing information for sildenafil citrate (VIAGRA, Pfizer, New York, NY, USA) recommends flexible dosing (50 mg initially, adjusted to 100 or 25 mg based on effectiveness and tolerability) in most men with erectile dysfunction (ED). In many men, however, 100 mg may be the most appropriate initial dose because it would reduce the need for titration and could prevent discouragement and treatment abandonment should 50 mg be insufficient. Results of two previously published double-blind, placebo-controlled sildenafil trials of similar design except for a fixed-dose vs flexible-dose regimen were analyzed. Relative to the flexible-dose, approximately one-third more men were satisfied with an initial and fixed dose of 100 mg. In addition, tolerability was similar, and improvements from baseline in outcomes on validated, ED-specific, patient-reported questionnaires were either similar (erectile function and the percentage of completely hard and fully rigid erections) or greater (emotional well-being and the overall sexual experience). The similarity in outcomes is not surprising given that almost 90% of the men in the flexible-dose trial titrated to 100 mg after 2 weeks. These data suggest prescription of an initial dose of 100 mg for men with ED, except in those for whom it is inappropriate. PMID:20596083

Whatever you do, don't look at the...: Evaluating guidance by an exclusionary attentional template.

PubMed

Beck, Valerie M; Luck, Steven J; Hollingworth, Andrew

2018-04-01

People can use a target template consisting of one or more features to guide attention and gaze to matching objects in a search array. But can we also use feature information to guide attention away from known irrelevant items? Some studies found a benefit from foreknowledge of a distractor feature, whereas others found a cost. Importantly, previous work has largely relied on end-of-trial manual responses; it is unclear how feature-guided avoidance might unfold as candidate objects are inspected. In the current experiments, participants were cued with a distractor feature to avoid, then performed a visual search task while eye movements were recorded. Participants initially fixated a to-be-avoided object more frequently than predicted by chance, but they also demonstrated avoidance of cue-matching objects later in the trial. When provided more time between cue stimulus and search array, participants continued to be initially captured by a cued-color item. Furthermore, avoidance of cue-matching objects later in the trial was not contingent on initial capture by a cue-matching object. These results suggest that the conflicting findings in previous negative-cue experiments may be explained by a mixture of two independent processes: initial attentional capture by memory-matching items and later avoidance of known irrelevant items. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Variables Affecting Pharmacy Students’ Patient Care Interventions during Advanced Pharmacy Practice Experiences

PubMed Central

Patterson, Brandon J.; Sen, Sanchita; Bingham, Angela L.; Bowen, Jane F.; Ereshefsky, Benjamin; Siemianowski, Laura A.

2016-01-01

Objective. To identify the temporal effect and factors associated with student pharmacist self-initiation of interventions during acute patient care advanced pharmacy practice experiences (APPE). Methods. During the APPE, student pharmacists at an academic medical center recorded their therapeutic interventions and who initiated the intervention throughout clinical rotations. At the end of the APPE student pharmacists completed a demographic survey. Results. Sixty-two student pharmacists were included. Factors associated with lower rates of self-initiated interventions were infectious diseases and pediatrics APPEs and an intention to pursue a postgraduate residency. Timing of the APPE, previous specialty elective course completion, and previous hospital experience did not result in any significant difference in self-initiated recommendations. Conclusion. Preceptors should not base practice experience expectations for self-initiated interventions on previous student experience or future intentions. Additionally, factors leading to lower rates of self-initiated interventions on infectious diseases or pediatrics APPEs should be explored. PMID:27756924

Rhizosphere Colonization and Control of Meloidogyne spp. by Nematode-trapping Fungi

PubMed Central

Persson, Christina; Jansson, Hans-Börje

1999-01-01

The ability of nematode-trapping fungi to colonize the rhizosphere of crop plants has been suggested to be an important factor in biological control of root-infecting nematodes. In this study, rhizosphere colonization was evaluated for 38 isolates of nematode-trapping fungi representing 11 species. In an initial screen, Arthrobotrys dactyloides, A. superba, and Monacrosporium ellipsosporum were most frequently detected in the tomato rhizosphere. In subsequent pot experiments these fungi and the non-root colonizing M. geophyropagum were introduced to soil in a sodium alginate matrix, and further tested both for establishment in the tomato rhizosphere and suppression of root-knot nematodes. The knob-forming M. ellipsosporum showed a high capacity to colonize the rhizosphere both in the initial screen and the pot experiments, with more than twice as many fungal propagules in the rhizosphere as in the root-free soil. However, neither this fungus nor the other nematode-trapping fungi tested reduced nematode damage to tomato plants. PMID:19270886

Free-standing leaping experiments with a power-autonomous elastic-spined quadruped

NASA Astrophysics Data System (ADS)

Pusey, Jason L.; Duperret, Jeffrey M.; Haynes, G. Clark; Knopf, Ryan; Koditschek, Daniel E.

2013-05-01

We document initial experiments with Canid, a freestanding, power-autonomous quadrupedal robot equipped with a parallel actuated elastic spine. Research into robotic bounding and galloping platforms holds scientific and engineering interest because it can both probe biological hypotheses regarding bounding and galloping mammals and also provide the engineering community with a new class of agile, efficient and rapidly-locomoting legged robots. We detail the design features of Canid that promote our goals of agile operation in a relatively cheap, conventionally prototyped, commercial off-the-shelf actuated platform. We introduce new measurement methodology aimed at capturing our robot's "body energy" during real time operation as a means of quantifying its potential for agile behavior. Finally, we present joint motor, inertial and motion capture data taken from Canid's initial leaps into highly energetic regimes exhibiting large accelerations that illustrate the use of this measure and suggest its future potential as a platform for developing efficient, stable, hence useful bounding gaits.

The persistence of the attentional bias to regularities in a changing environment.

PubMed

Yu, Ru Qi; Zhao, Jiaying

2015-10-01

The environment often is stable, but some aspects may change over time. The challenge for the visual system is to discover and flexibly adapt to the changes. We examined how attention is shifted in the presence of changes in the underlying structure of the environment. In six experiments, observers viewed four simultaneous streams of objects while performing a visual search task. In the first half of each experiment, the stream in the structured location contained regularities, the shapes in the random location were randomized, and gray squares appeared in two neutral locations. In the second half, the stream in the structured or the random location may change. In the first half of all experiments, visual search was facilitated in the structured location, suggesting that attention was consistently biased toward regularities. In the second half, this bias persisted in the structured location when no change occurred (Experiment 1), when the regularities were removed (Experiment 2), or when new regularities embedded in the original or novel stimuli emerged in the previously random location (Experiments 3 and 6). However, visual search was numerically but no longer reliably faster in the structured location when the initial regularities were removed and new regularities were introduced in the previously random location (Experiment 4), or when novel random stimuli appeared in the random location (Experiment 5). This suggests that the attentional bias was weakened. Overall, the results demonstrate that the attentional bias to regularities was persistent but also sensitive to changes in the environment.

Changing scenes: memory for naturalistic events following change blindness.

PubMed

Mäntylä, Timo; Sundström, Anna

2004-11-01

Research on scene perception indicates that viewers often fail to detect large changes to scene regions when these changes occur during a visual disruption such as a saccade or a movie cut. In two experiments, we examined whether this relative inability to detect changes would produce systematic biases in event memory. In Experiment 1, participants decided whether two successively presented images were the same or different, followed by a memory task, in which they recalled the content of the viewed scene. In Experiment 2, participants viewed a short video, in which an actor carried out a series of daily activities, and central scenes' attributes were changed during a movie cut. A high degree of change blindness was observed in both experiments, and these effects were related to scene complexity (Experiment 1) and level of retrieval support (Experiment 2). Most important, participants reported the changed, rather than the initial, event attributes following a failure in change detection. These findings suggest that attentional limitations during encoding contribute to biases in episodic memory.

Explaining the forgetting bias effect on value judgments: The influence of memory for a past test.

PubMed

Rhodes, Matthew G; Witherby, Amber E; Castel, Alan D; Murayama, Kou

2017-04-01

People often feel that information that was forgotten is less important than remembered information. Prior work has shown that participants assign higher importance to remembered information while undervaluing forgotten information. The current study examined two possible accounts of this finding. In three experiments, participants studied lists of words in which each word was randomly assigned a point value denoting the value of remembering the word. Following the presentation of each list participants engaged in a free recall test. After the presentation of all lists participants were shown each of the words they had studied and asked to recall the point value that was initially paired with each word. Experiment 1 tested a fluency-based account by presenting items for value judgments in a low-fluency or high-fluency format. Experiment 2 examined whether value judgments reflect attributions based on the familiarity of an item when value judgments are made. Finally, in Experiment 3, we evaluated whether participants believe that forgotten words are less important by having them judge whether an item was initially recalled or forgotten prior to making a value judgment. Manipulating the fluency of an item presented for judgment had no influence on value ratings (Experiment 1) and familiarity exerted a limited influence on value judgments (Experiment 2). More importantly, participants' value judgments appeared to reflect a theory that remembered information is more valuable than forgotten information (Experiment 3). Overall, the present work suggests that individuals may apply a theory about remembering and forgetting to retrospectively assess the value of information.

Using Large-Eddy Simulation to Explore Microphysical Precursor Conditions for Precipitation Initiation in Marine Stratocumulus

NASA Astrophysics Data System (ADS)

Chandler, H.; Mechem, D. B.; Fridlind, A. M.; Ackerman, A. S.

2016-12-01

Although the classical model of how a population of cloud droplets grows to precipitation-sized drops through the condensation and coalescence processes is well accepted, it does not fully address the history of how nascent precipitation drops come about in warm clouds. Precipitation initiation is influenced by the properties of the cloud drop distribution and in bulk large-eddy simulation (LES) models is parameterized by autoconversion. Double-moment formulations of autoconversion rate generally weight cloud water content qc more than cloud drop concentration Nc (e.g., qc2.47Nc-1.79, Khairoutdinov and Kogan 2000) and precipitation rate scalings derived from field campaigns suggest a dominance of thermodynamic over aerosol factors. However, the mechanisms that drive precipitation initiation in any given cloud are still uncertain. From the perspective of autoconversion, do the regions where precipitation onset occurs experience large liquid water content values (large qc), or are they anomalously clean (small Nc)? Recent laboratory measurements suggest that fluctuations in the supersaturation field may also play a role in precipitation initiation. This study explores the nature of precursor conditions to precipitation onset within marine stratocumulus clouds. We apply an LES model with size-resolving microphysics to a case of marine stratocumulus over the eastern north Atlantic. Backward trajectories originating from regions of precipitation initiation are calculated from the time-evolving LES flow fields to examine the history of fluid parcels that ultimately contain embryonic precipitation.

Microgravity Effects on the Early Events of Biological Nitrogen Fixation in Medicago Truncatula: Results from the SyNRGE Experiment

NASA Astrophysics Data System (ADS)

Stutte, Gary W.; Roberts, Michael S.

2013-02-01

SyNRGE (Symbiotic Nodulation in a Reduced Gravity Environment) was a sortie mission on STS-135 in the Biological Research in Canisters (BRIC) hardware to study the effect of μg on a plant-microbe symbiosis resulting in biological nitrogen fixation. Medicago truncatula, a model species for the legume family, was inoculated with its bacterial symbiont, Sinorhizobium meliloti, to observe early biomolecular events associated with infection and nodulation in Petri Dish Fixation Units (PDFU’s). Two sets of experiments were conducted in orbit and in 24-hour delayed ground controls. Experiments were designed to determine if S. meliloti would infect M. truncatula and initiate biomolecular changes associated with nodule formation and if the μg environment altered the host plant and/or bacteria to induce nodule formation upon return to 1g. Initial analysis results demonstrate that the legumes and bacteria cultivated in μg have potential to develop a symbiotic interaction, but suggest that μg alters their ability to form nodules upon return to 1g. (Research supported by NASA ESMD/ Advance Capabilities Division grant NNX10AR09A)

Stimulus Threat and Exposure Context Modulate the Effect of Mere Exposure on Approach Behaviors.

PubMed

Young, Steven G; Jones, Isaiah F; Claypool, Heather M

2016-01-01

Mere-exposure (ME) research has found that initially neutral objects made familiar are preferred relative to novel objects. Recent work extends these preference judgments into the behavioral domain by illustrating that mere exposure prompts approach-oriented behavior toward familiar stimuli. However, no investigations have examined the effect of mere exposure on approach-oriented behavior toward threatening stimuli. The current work examines this issue and also explores how exposure context interacts with stimulus threat to influence behavioral tendencies. In two experiments participants were presented with both mere-exposed and novel stimuli and approach speed was assessed. In the first experiment, when stimulus threat was presented in a homogeneous format (i.e., participants viewed exclusively neutral or threatening stimuli), ME potentiated approach behaviors for both neutral and threatening stimuli. However, in the second experiment, in which stimulus threat was presented in a heterogeneous fashion (i.e., participants viewed both neutral and threatening stimuli), mere exposure facilitated approach only for initially neutral stimuli. These results suggest that ME effects on approach behaviors are highly context sensitive and depend on both stimulus valence and exposure context. Further implications of these findings for the ME literature are discussed.

Stimulus Threat and Exposure Context Modulate the Effect of Mere Exposure on Approach Behaviors

PubMed Central

Young, Steven G.; Jones, Isaiah F.; Claypool, Heather M.

2016-01-01

Mere-exposure (ME) research has found that initially neutral objects made familiar are preferred relative to novel objects. Recent work extends these preference judgments into the behavioral domain by illustrating that mere exposure prompts approach-oriented behavior toward familiar stimuli. However, no investigations have examined the effect of mere exposure on approach-oriented behavior toward threatening stimuli. The current work examines this issue and also explores how exposure context interacts with stimulus threat to influence behavioral tendencies. In two experiments participants were presented with both mere-exposed and novel stimuli and approach speed was assessed. In the first experiment, when stimulus threat was presented in a homogeneous format (i.e., participants viewed exclusively neutral or threatening stimuli), ME potentiated approach behaviors for both neutral and threatening stimuli. However, in the second experiment, in which stimulus threat was presented in a heterogeneous fashion (i.e., participants viewed both neutral and threatening stimuli), mere exposure facilitated approach only for initially neutral stimuli. These results suggest that ME effects on approach behaviors are highly context sensitive and depend on both stimulus valence and exposure context. Further implications of these findings for the ME literature are discussed. PMID:27965614

Photoactive high explosives: linear and nonlinear photochemistry of petrin tetrazine chloride.

PubMed

Greenfield, Margo T; McGrane, Shawn D; Bolme, Cindy A; Bjorgaard, Josiah A; Nelson, Tammie R; Tretiak, Sergei; Scharff, R Jason

2015-05-21

Pentaerythritol tetranitrate (PETN), a high explosive, initiates with traditional shock and thermal mechanisms. In this study, the tetrazine-substituted derivative of PETN, pentaerythritol trinitrate chlorotetrazine (PetrinTzCl), is being investigated for a photochemical initiation mechanism that could allow control over the chemistry contributing to decomposition leading to initiation. PetrinTzCl exhibits a photochemical quantum yield (QYPC) at 532 nm not evident with PETN. Using static spectroscopic methods, we observe energy absorption on the tetrazine (Tz) ring that results in photodissociation yielding N2, Cl-CN, and Petrin-CN as the major photoproducts. The QYPC was enhanced with increasing irradiation intensity. Experiment and theoretical calculations imply this excitation mechanism follows sequential photon absorption. Dynamic simulations demonstrate that the relaxation mechanism leading to the observed photochemistry in PetrinTzCl is due to vibrational excitation during internal conversion. PetrinTzCl's single photon stability and intensity dependence suggest this material could be stable in ambient lighting, yet possible to initiate with short-pulsed lasers.

Self-Determination and U.S. Support of Insurgents: A Policy-Analysis Model

DTIC Science & Technology

1988-01-01

parallels the European Convention model. The American Convention on Human Rights21 is the basis for an Inter -American human rights system which has its...fundamental change takes place among states and in the context of state-initiated action.42 Although they do not necessarily have the same capacities as...ability to adapt to the ever- changing circumstances in which conflicts arise. The global experience, Stone suggested, has proven that literal

77 FR 40628 - HUD's Fiscal Year (FY) 2012 Transformation Initiative: Natural Experiments Research Grant Program...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-07-10

... DEPARTMENT OF HOUSING AND URBAN DEVELOPMENT [Docket No. FR-5600-N-18-C-1] HUD's Fiscal Year (FY) 2012 Transformation Initiative: Natural Experiments Research Grant Program, Cancellation AGENCY: Office... Availability (NOFA) ``Transformation Initiative: Natural Experiments Grant Program'' on Grants.gov . The close...

Conformational plasticity of RepB, the replication initiator protein of promiscuous streptococcal plasmid pMV158

PubMed Central

Boer, D. Roeland; Ruiz-Masó, José Angel; Rueda, Manuel; Petoukhov, Maxim V.; Machón, Cristina; Svergun, Dmitri I.; Orozco, Modesto; del Solar, Gloria; Coll, Miquel

2016-01-01

DNA replication initiation is a vital and tightly regulated step in all replicons and requires an initiator factor that specifically recognizes the DNA replication origin and starts replication. RepB from the promiscuous streptococcal plasmid pMV158 is a hexameric ring protein evolutionary related to viral initiators. Here we explore the conformational plasticity of the RepB hexamer by i) SAXS, ii) sedimentation experiments, iii) molecular simulations and iv) X-ray crystallography. Combining these techniques, we derive an estimate of the conformational ensemble in solution showing that the C-terminal oligomerisation domains of the protein form a rigid cylindrical scaffold to which the N-terminal DNA-binding/catalytic domains are attached as highly flexible appendages, featuring multiple orientations. In addition, we show that the hinge region connecting both domains plays a pivotal role in the observed plasticity. Sequence comparisons and a literature survey show that this hinge region could exists in other initiators, suggesting that it is a common, crucial structural element for DNA binding and manipulation. PMID:26875695

Effect of initial moisture content on the in-vessel composting under air pressure of organic fraction of municipal solid waste in Morocco.

PubMed

Makan, Abdelhadi; Assobhei, Omar; Mountadar, Mohammed

2013-01-03

This study aimed to evaluate the effect of initial moisture content on the in-vessel composting under air pressure of organic fraction of municipal solid waste in Morocco in terms of internal temperature, produced gases quantity, organic matter conversion rate, and the quality of the final composts.For this purpose, in-vessel bioreactor was designed and used to evaluate both appropriate initial air pressure and appropriate initial moisture content for the composting process. Moreover, 5 experiments were carried out within initial moisture content of 55%, 65%, 70%, 75% and 85%. The initial air pressure and the initial moisture content of the mixture showed a significant effect on the aerobic composting. The experimental results demonstrated that for composting organic waste, relatively high moisture contents are better at achieving higher temperatures and retaining them for longer times.This study suggested that an initial moisture content of around 75%, under 0.6 bar, can be considered as being suitable for efficient composting of organic fraction of municipal solid waste. These last conditions, allowed maximum value of temperature and final composting product with good physicochemical properties as well as higher organic matter degradation and higher gas production. Moreover, final compost obtained showed good maturity levels and can be used for agricultural applications.

The use of a science experiment curriculum with mothers and their preschool children in an Even Start literacy setting: A case study

NASA Astrophysics Data System (ADS)

Cadou, Judith Ann

The purpose of this study was to explore systematically the use of a science experiment curriculum in an Even Start program setting through an in-depth description of the verbal and nonverbal interaction of preschool children and their mothers engaged in constructing knowledge through active science experiment exploration, representative notation, and related informational text experiences. It also sought to document the mothers' perceptions of science exploration as a facilitator for their children's literacy and their awareness of ways to support such growth. Two in-depth studies were presented to profile, in detail, the process of mother and child meaning making within the structure of a science explorations context. An additional eight mother-child dyads participated for purposes of adding breadth to the study. Behaviors were documented through (a) videotape transcriptions of the mother-child interaction in this science inquiry context, (b) observation, (c) field notes, and (d) open-ended interviews with the mothers. Data were analyzed using the constant comparative method. The findings of this naturalistic study suggest the use of a linked mother-child dyad learning and literacy development process using prediction, experimentation, observation, and reflection, combined with related meaning-making verbal interaction, documentation, and reading, facilitated the child's knowledge acquisition, learning interests, and learning methodologies. Specifically, (a) the initiating setup for prediction placed the child at the center of her or his own inquiry and initiated verbal communication; (b) mother and child used the scientific thinking routine of predict, act on objects and observe, discover, evaluate, and make decisions, to be documented in second-level notation, as a mental organizer and scaffolding for inquiry and communication between them; (c) the children showed development in conceptual understanding within the context of active science exploration and across science units; (d) the children used the representative drawing and labeling of the experiment experience for extended experimentation and meaning making, thus using second-level notation for functional purposes; (e) the children showed increased initiative with expository text related to the experiment experiences; and (f) the mothers voiced perception of their children's and their own learning and a sense of efficacy in facilitating their children's learning.

Association of Specific Traumatic Experiences With Alcohol Initiation and Transitions to Problem Use in European American and African American Women.

PubMed

Werner, Kimberly B; Sartor, Carolyn E; McCutcheon, Vivia V; Grant, Julia D; Nelson, Elliot C; Heath, Andrew C; Bucholz, Kathleen K

2016-11-01

The aims of this study were to (i) characterize racial differences in alcohol involvement and (ii) examine the risk conferred by specific trauma exposures and posttraumatic stress disorder (PTSD) for different stages of alcohol involvement in European American (EA) and African American (AA) women. Data are from the Missouri Adolescent Female Twins Study (N = 3,787, 14.6% AA; mean age at most recent interview = 24.5 [SD 2.8]). Trauma exposures (e.g., sexual abuse [SA], physical abuse [PA], witnessing another person being killed or injured, experiencing an accident, and experiencing a disaster) were modeled as time-varying predictors of alcohol initiation, transition to first alcohol use disorder (AUD) symptom, and transition to AUD diagnosis using Cox proportional hazards regression while taking into account other substance involvement, parental characteristics, and commonly co-occurring psychiatric disorders. In EA women only, SA was associated with alcohol initiation prior to the age of 14, PA predicted transition from initiation to first AUD symptom, and PA, witnessing injury or death, and SA predicted transition to AUD diagnosis. No association was discovered between trauma exposures or PTSD for any stage of alcohol involvement in AA women. Results reveal trauma experiences as important contributors to all stages of alcohol involvement in EA women only, with different trauma types conferring risk for each stage of alcohol involvement. PTSD was not revealed as a significant predictor of AUD in EA or AA women, suggesting trauma, independent of PTSD, directly contributes to alcohol involvement. Findings highlight the importance of considering racial differences when developing etiologic models of the association of traumatic experiences with alcohol involvement. Copyright © 2016 by the Research Society on Alcoholism.

Initial experience with laparoscopic sleeve gastrectomy by a novice bariatric team in an established bariatric center--a review of literature and initial results.

PubMed

Dey, Ashish; Mittal, Tarun; Malik, Vinod K

2013-04-01

Laparoscopic sleeve gastrectomy (LSG) is a highly successful approach to morbid obesity with low incidence of complications. The literature suggests a learning curve of 50-100 cases for attaining proficiency and reducing the complication rates for laparoscopic bariatric surgery. The aims of this paper were to review the literature of initial cases by bariatric surgeons worldwide and to report the experience of initial 50 cases of LSG by a novice bariatric team in a single center. The objective was to evaluate the outcomes for laparoscopic bariatric surgery in the first 50 patients by a novice team of bariatric surgeons in an already established bariatric surgery program with short-term follow-up. All surgeries were done by a new bariatric team who underwent laparoscopic fellowship training under a bariatric team with an experience of over 600 bariatric procedures. Fifty consecutive patients from March 2010 to January 2012 were offered LSG and followed up for a minimum of 6 months. Weight loss and comorbidity resolution were tabulated and assessed. Mean preoperative and postoperative BMIs were 46.6 and 35.7 kg/m2, respectively. There were no life threatening postoperative complications or mortality. The median percent excess weight loss was 50.3% at the end of 6 months. Comorbidity resolution values were 96% for obstructive sleep apnea, 89% for diabetes mellitus, and 87% for joint pains, among the most common comorbidities. LSG is effective in achieving weight loss and in improving comorbidities with minimal complications even at the hands of novice bariatric surgeons with good laparoscopic skills and adequate bariatric training.

Tiger salamanders' (Ambystoma tigrinum) response learning and usage of visual cues.

PubMed

Kundey, Shannon M A; Millar, Roberto; McPherson, Justin; Gonzalez, Maya; Fitz, Aleyna; Allen, Chadbourne

2016-05-01

We explored tiger salamanders' (Ambystoma tigrinum) learning to execute a response within a maze as proximal visual cue conditions varied. In Experiment 1, salamanders learned to turn consistently in a T-maze for reinforcement before the maze was rotated. All learned the initial task and executed the trained turn during test, suggesting that they learned to demonstrate the reinforced response during training and continued to perform it during test. In a second experiment utilizing a similar procedure, two visual cues were placed consistently at the maze junction. Salamanders were reinforced for turning towards one cue. Cue placement was reversed during test. All learned the initial task, but executed the trained turn rather than turning towards the visual cue during test, evidencing response learning. In Experiment 3, we investigated whether a compound visual cue could control salamanders' behaviour when it was the only cue predictive of reinforcement in a cross-maze by varying start position and cue placement. All learned to turn in the direction indicated by the compound visual cue, indicating that visual cues can come to control their behaviour. Following training, testing revealed that salamanders attended to stimuli foreground over background features. Overall, these results suggest that salamanders learn to execute responses over learning to use visual cues but can use visual cues if required. Our success with this paradigm offers the potential in future studies to explore salamanders' cognition further, as well as to shed light on how features of the tiger salamanders' life history (e.g. hibernation and metamorphosis) impact cognition.

Vigilant conservatism in evaluating communicated information

PubMed Central

Johansson, Petter; Hall, Lars; Mercier, Hugo

2018-01-01

In the absence of other information, people put more weight on their own opinion than on the opinion of others: they are conservative. Several proximal mechanisms have been suggested to account for this finding. One of these mechanisms is that people cannot access reasons for other people’s opinions, but they can access the reasons for their own opinions—whether they are the actual reasons that led them to hold the opinions (rational access to reasons), or post-hoc constructions (biased access to reasons). In four experiments, participants were asked to provide an opinion, and then faced with another participant’s opinion and asked if they wanted to revise their initial opinion. Some questions were manipulated so that the advice participants were receiving was in fact their own opinion, while what they thought was their own opinion was in fact not. In all experiments, the participants were consistently biased towards what they thought was their own opinion, showing that conservativeness cannot be explained by rational access to reasons, which should have favored the advice. One experiment revealed that conservativeness was not decreased under time pressure, suggesting that biased access to reasons is an unlikely explanation for conservativeness. The experiments also suggest that repetition plays a role in advice taking, with repeated opinions being granted more weight than non-fluent opinions. Our results are not consistent with any of the established proximal explanations for conservatism. Instead, we suggest an ultimate explanation—vigilant conservatism—that sees conservatism as adaptive since receivers should be wary of senders’ interests, as they rarely perfectly converge with theirs. PMID:29320515

Vigilant conservatism in evaluating communicated information.

PubMed

Trouche, Emmanuel; Johansson, Petter; Hall, Lars; Mercier, Hugo

2018-01-01

In the absence of other information, people put more weight on their own opinion than on the opinion of others: they are conservative. Several proximal mechanisms have been suggested to account for this finding. One of these mechanisms is that people cannot access reasons for other people's opinions, but they can access the reasons for their own opinions-whether they are the actual reasons that led them to hold the opinions (rational access to reasons), or post-hoc constructions (biased access to reasons). In four experiments, participants were asked to provide an opinion, and then faced with another participant's opinion and asked if they wanted to revise their initial opinion. Some questions were manipulated so that the advice participants were receiving was in fact their own opinion, while what they thought was their own opinion was in fact not. In all experiments, the participants were consistently biased towards what they thought was their own opinion, showing that conservativeness cannot be explained by rational access to reasons, which should have favored the advice. One experiment revealed that conservativeness was not decreased under time pressure, suggesting that biased access to reasons is an unlikely explanation for conservativeness. The experiments also suggest that repetition plays a role in advice taking, with repeated opinions being granted more weight than non-fluent opinions. Our results are not consistent with any of the established proximal explanations for conservatism. Instead, we suggest an ultimate explanation-vigilant conservatism-that sees conservatism as adaptive since receivers should be wary of senders' interests, as they rarely perfectly converge with theirs.

LDEF electronic systems: Successes, failures, and lessons

NASA Technical Reports Server (NTRS)

Miller, Emmett; Porter, Dave; Smith, Dave; Brooks, Larry; Levorsen, Joe; Mulkey, Owen

1991-01-01

Following the Long Duration Exposure Facility (LDEF) retrieval, the Systems Special Investigation Group (SIG) participated in an extensive series of tests of various electronic systems, including the NASA provided data and initiate systems, and some experiment systems. Overall, these were found to have performed remarkably well, even though most were designed and tested under limited budgets and used at least some nonspace qualified components. However, several anomalies were observed, including a few which resulted in some loss of data. The postflight test program objectives, observations, and lessons learned from these examinations are discussed. All analyses are not yet complete, but observations to date will be summarized, including the Boeing experiment component studies and failure analysis results related to the Interstellar Gas Experiment. Based upon these observations, suggestions for avoiding similar problems on future programs are presented.

Reentry Program and Social Work Education: Training the Next Generation of Criminal Justice Social Workers.

PubMed

Franke, Nancy D; Treglia, Dan; Cnaan, Ram A

2017-01-01

Social work plays a marginal role in opposing the trend of mass incarceration and high rates of recidivism, and social work education offers limited opportunities for students to specialize in working with people who are currently or were previously incarcerated. How to train students of social work to work against mass-incarceration is still challenging. The authors devised and implemented an in-school social service agency devoted to working with people pre and post release from a prison system. The agency is a field practicum setting where interested students study and practice reentry work. In this article, the authors describe and assess the educational merit of this in-school agency. Findings from surveys of students and alumni suggest that the program attained its educational goals of connecting classroom education to practice experience and training students for careers in the criminal justice system. The authors also discuss pending challenges. The experience of the Goldring Reentry Initiative suggests that by developing their own social work agencies, the authors may be able to heighten their students educational experience and expand their contribution to social work practice broadly.

Preparing hearts and minds: cardiac slowing and a cortical inhibitory network.

PubMed

Jennings, J R; van der Molen, M W; Tanase, C

2009-11-01

Preparing for a cued, speeded response induces a set of physiological changes. A review of the psychophysiology of preparation suggested that inhibition of action was an important process among the constellation of changes constituting attentive preparation. The current experiment combined event-related functional magnetic resonance imaging and cardiac inter-beat interval measures in an experiment that compared preparing for a response, watching stimuli without responding, and responding in the absence of preparation. Ten college-aged participants were tested in an initial psychophysiological experiment followed by two scanning sessions during which reverse spiral imaging was performed concurrent with inter-beat interval measurement. Two analytic approaches were used to confirm blood oxygenation level dependent responses during preparation, and these converged to show inferior prefrontal and related subthalamic nuclei activity in the context of other known changes related to brain attentional networks. Subthalamic nuclei changes were related to the depth of preparatory cardiac deceleration. This pattern of findings suggests that preparation involves the activation of a complex inhibitory neural network implicating brain and autonomic nervous systems.

What happened (and what didn’t): Discourse constraints on encoding of plausible alternatives

PubMed Central

Fraundorf, Scott H.; Benjamin, Aaron S.; Watson, Duane G.

2013-01-01

Three experiments investigated how font emphasis influences reading and remembering discourse. Although past work suggests that contrastive pitch contours benefit memory by promoting encoding of salient alternatives, it is unclear both whether this effect generalizes to other forms of linguistic prominence and how the set of alternatives is constrained. Participants read discourses in which some true propositions had salient alternatives (e.g., British scientists found the endangered monkey when the discourse also mentioned French scientists) and completed a recognition memory test. In Experiments 1 and 2, font emphasis in the initial presentation increased participants’ ability to later reject false statements about salient alternatives but not about unmentioned items (e.g., Portuguese scientists). In Experiment 3, font emphasis helped reject false statements about plausible alternatives, but not about less plausible alternatives that were nevertheless established in the discourse. These results suggest readers encode a narrow set of only those alternatives plausible in the particular discourse. They also indicate that multiple manipulations of linguistic prominence, not just prosody, can lead to consideration of alternatives. PMID:24014934

Investigation of particle and vapor wall-loss effects on controlled wood-smoke smog-chamber experiments

NASA Astrophysics Data System (ADS)

Bian, Q.; May, A. A.; Kreidenweis, S. M.; Pierce, J. R.

2015-10-01

Smog chambers are extensively used to study processes that drive gas and particle evolution in the atmosphere. A limitation of these experiments is that particles and gas-phase species may be lost to chamber walls on shorter timescales than the timescales of the atmospheric processes being studied in the chamber experiments. These particle and vapor wall losses have been investigated in recent studies of secondary organic aerosol (SOA) formation, but they have not been systematically investigated in experiments of primary emissions from combustion. The semi-volatile nature of combustion emissions (e.g. from wood smoke) may complicate the behavior of particle and vapor wall deposition in the chamber over the course of the experiments due to the competition between gas/particle and gas/wall partitioning. Losses of vapors to the walls may impact particle evaporation in these experiments, and potential precursors for SOA formation from combustion may be lost to the walls, causing underestimations of aerosol yields. Here, we conduct simulations to determine how particle and gas-phase wall losses contributed to the observed evolution of the aerosol during experiments in the third Fire Lab At Missoula Experiment (FLAME III). We use the TwO-Moment Aerosol Sectional (TOMAS) microphysics algorithm coupled with the organic volatility basis set (VBS) and wall-loss formulations to examine the predicted extent of particle and vapor wall losses. We limit the scope of our study to the dark periods in the chamber before photo-oxidation to simplify the aerosol system for this initial study. Our model simulations suggest that over one-third of the initial particle-phase organic mass (41 %) was lost during the experiments, and over half of this particle-organic mass loss was from direct particle wall loss (65 % of the loss) with the remainder from evaporation of the particles driven by vapor losses to the walls (35 % of the loss). We perform a series of sensitivity tests to understand uncertainties in our simulations. Uncertainty in the initial wood-smoke volatility distribution contributes 18 % uncertainty to the final particle-organic mass remaining in the chamber (relative to base-assumption simulation). We show that the total mass loss may depend on the effective saturation concentration of vapor with respect to the walls as these values currently vary widely in the literature. The details of smoke dilution during the filling of smog chambers may influence the mass loss to the walls, and a dilution of ~ 25:1 during the experiments increased particle-organic mass loss by 33 % compared to a simulation where we assume the particles and vapors are initially in equilibrium in the chamber. Finally, we discuss how our findings may influence interpretations of emission factors and SOA production in wood-smoke smog-chamber experiments.

Investigation of particle and vapor wall-loss effects on controlled wood-smoke smog-chamber experiments

NASA Astrophysics Data System (ADS)

Bian, Q.; May, A. A.; Kreidenweis, S. M.; Pierce, J. R.

2015-06-01

Smog chambers are extensively used to study processes that drive gas and particle evolution in the atmosphere. A limitation of these experiments is that particles and gas-phase species may be lost to chamber walls on shorter timescales than the timescales of the atmospheric processes being studied in the chamber experiments. These particle and vapor wall losses have been investigated in recent studies of secondary organic aerosol (SOA) formation, but they have not been systematically investigated in experiments of primary emissions from combustion. The semi-volatile nature of combustion emissions (e.g. from wood smoke) may complicate the behavior of particle and vapor wall deposition in the chamber over the course of the experiments due to the competition between gas/particle and gas/wall partitioning. Losses of vapors to the walls may impact particle evaporation in these experiments, and potential precursors for SOA formation from combustion may be lost to the walls, causing underestimates of aerosol yields. Here, we conduct simulations to determine how particle and gas-phase wall losses contributed to the observed evolution of the aerosol during experiments in the third Fire Lab At Missoula Experiment (FLAME III). We use the TwO-Moment Aerosol Sectional (TOMAS) microphysics algorithm coupled with the organic volatility basis set (VBS) and wall-loss formulations to examine the predicted extent of particle and vapor wall losses. We limit the scope of our study to the dark periods in the chamber before photo-oxidation to simplify the aerosol system for this initial study. Our model simulations suggest that over one third of the initial particle-phase organic mass (36%) was lost during the experiments, and roughly half of this particle organic mass loss was from direct particle wall loss (56% of the loss) with the remainder from evaporation of the particles driven by vapor losses to the walls (44% of the loss). We perform a series of sensitivity tests to understand uncertainties in our simulations. Uncertainty in the initial wood-smoke volatility distribution contributes 23% uncertainty to the final particle organic mass remaining in the chamber (relative to base-assumptions simulation). We show that the total mass loss may depend on the effective saturation concentration of vapor with respect to the walls as these values currently vary widely in the literature. The details of smoke dilution during the filling of smog chambers may influence the mass loss to the walls, and a dilution of ~ 25:1 during the experiments increased particle organic mass loss by 64% compared to a simulation where we assume the particles and vapors are initially in equilibrium in the chamber. Finally, we discuss how our findings may influence interpretations of emission factors and SOA production in wood-smoke smog-chamber experiments.

Eye Movement Patterns for Novice Teen Drivers Does 6 Months of Driving Experience Make a Difference?

PubMed Central

Olsen, Erik C. B.; Lee, Suzanne E.; Simons-Morton, Bruce G.

2009-01-01

Attention to the road is essential to safe driving, but the development of appropriate eye glance scanning behaviors may require substantial driving experience. Novice teen drivers may focus almost exclusively on the road ahead rather than scanning the mirrors, and when performing secondary tasks, they may spend more time with eyes on the task than on the road. This paper examines the extent to which the scanning of novice teens improves with experience. For this study, 18 novice teen (younger than 17.5 years old) and 18 experienced adult drivers performed a set of in-vehicle tasks and a baseline driving segment on a test track, the teens within 4 weeks of licensure and then again 6 months later. This paper addresses the following questions: Did teen eye glance performance improve from initial assessment? Did teens and adults still differ after 6 months? Results for some tasks showed that rearview and left mirror–window (LM-W) glances improved for teens from initial testing to the 6-month follow-up and that some differences between teens and adults at initial testing were no longer significant at the 6-month follow-up, suggesting significant learning effects. The frequency of rearview and LM-W glances during secondary tasks improved among teens at the 6-month follow-up, but teens still had significantly fewer glances to mirrors than did adults when engaged in a secondary task. PMID:19763225

A two-dimensional phase separation on the spherical surface of the metallic glass Au55Pb22.5Sb22.5

NASA Technical Reports Server (NTRS)

Lee, M. C.; Johnson, W. L.

1982-01-01

Recent experiments indicate that a phase separation in a spherical sample of the metallic glass Au55Pb22.5Sb22.5 occurs near the surface of the sphere. This strongly suggests either a contribution of surface-free energy to the decomposition process or a possible influence of near surface impurities absorbed during synthesis of the sphere. The surface phase separation has been studied as a function of cooling rate of the sphere. At high cooling rates (small sphere sizes), the surface separation disappears altogether suggesting that the surface of the parent liquid droplet is initially homogeneous.

The influence of aging on attentional refreshing and articulatory rehearsal during working memory on later episodic memory performance.

PubMed

Loaiza, Vanessa M; McCabe, David P

2013-01-01

We investigated age-related changes in two proposed mechanisms of maintenance in working memory, articulatory rehearsal, and attentional refreshing, by examining the consequences of manipulating the opportunity for each on delayed recall. Both experiments utilized modified operation span tasks to vary the opportunity for articulatory rehearsal (Experiment 1) and attentional refreshing opportunities (Experiment 2). In both experiments, episodic memory was tested for items that had been initially studied during the respective operation span task. Older adults' episodic memory benefited less from opportunities for refreshing than younger adults. In contrast, articulatory rehearsal opportunities did not influence episodic memory for either age group. The results suggest that attentional refreshing, and not articulatory rehearsal, is important during working memory in order to bind more accessible traces at later tests, which appears to be more deficient in older adults than younger adults.

Contribution to study of interfaces instabilities in plane, cylindrical and spherical geometry

NASA Astrophysics Data System (ADS)

Toque, Nathalie

1996-12-01

This thesis proposes several experiments of hydrodynamical instabilities which are studied, numerically and theoretically. The experiments are in plane and cylindrical geometry. Their X-ray radiographies show the evolution of an interface between two solid media crossed by a detonation wave. These materials are initially solid. They become liquide under shock wave or stay between two phases, solid and liquid. The numerical study aims at simulating with the codes EAD and Ouranos, the interfaces instabilities which appear in the experiments. The experimental radiographies and the numerical pictures are in quite good agreement. The theoretical study suggests to modelise a spatio-temporal part of the experiments to obtain the quantitative development of perturbations at the interfaces and in the flows. The models are linear and in plane, cylindrical and spherical geometry. They preceed the inoming study of transition between linear and non linear development of instabilities in multifluids flows crossed by shock waves.

Training Attentional Control Improves Cognitive and Motor Task Performance.

PubMed

Ducrocq, Emmanuel; Wilson, Mark; Vine, Sam; Derakshan, Nazanin

2016-10-01

Attentional control is a necessary function for the regulation of goal-directed behavior. In three experiments we investigated whether training inhibitory control using a visual search task could improve task-specific measures of attentional control and performance. In Experiment 1 results revealed that training elicited a near-transfer effect, improving performance on a cognitive (antisaccade) task assessing inhibitory control. In Experiment 2 an initial far-transfer effect of training was observed on an index of attentional control validated for tennis. The principal aim of Experiment 3 was to expand on these findings by assessing objective gaze measures of inhibitory control during the performance of a tennis task. Training improved inhibitory control and performance when pressure was elevated, confirming the mechanisms by which cognitive anxiety impacts performance. These results suggest that attentional control training can improve inhibition and reduce taskspecific distractibility with promise of transfer to more efficient sporting performance in competitive contexts.

Proposal for a United Nations Basic Space Technology Initiative

NASA Astrophysics Data System (ADS)

Balogh, Werner

Putting space technology and its applications to work for sustainable economic and social development is the primary objective of the United Nations Programme on Space Applications, launched in 1971. A specific goal for achieving this objective is to establish a sustainable national space capacity. The traditional line of thinking has supported a logical progression from building capacity in basic space science, to using space applications and finally - possibly - to establishing indigenous space technology capabilities. The experience in some countries suggests that such a strict line of progression does not necessarily hold true and that priority given to the establishment of early indigenous space technology capabilities may contribute to promoting the operational use of space applications in support of sustainable economic and social development. Based on these findings and on the experiences with the United Nations Basic Space Science Initiative (UNBSSI) as well as on a series of United Nations/International Academy of Astronautics Workshops on Small Satellites in the Service of Developing Countries, the United Nations Office for Outer Space Affairs (UNOOSA) is considering the launch of a dedicated United Nations Basic Space Technology Initiative (UNBSTI). The initiative would aim to contribute to capacity building in basic space technology and could include, among other relevant fields, activities related to the space and ground segments of small satellites and their applications. It would also provide an international framework for enhancing cooperation between all interested actors, facilitate the exchange of information on best practices, and contribute to standardization efforts. It is expected that these activities would advance the operational use of space technology and its applications in an increasing number of space-using countries and emerging space nations. The paper reports on these initial considerations and on the potential value-adding role the United Nations could play with such an initiative.

Experience of initiating collaboration of traditional healers in managing HIV and AIDS in Tanzania

PubMed Central

Kayombo, Edmund J; Uiso, Febronia C; Mbwambo, Zakaria H; Mahunnah, Rogasian L; Moshi, Mainen J; Mgonda, Yasin H

2007-01-01

Collaboration between traditional healers and biomedical practitioners is now being accepted by many African countries south of the Sahara because of the increasing problem of HIV/AIDS. The key problem, however, is how to initiate collaboration between two health systems which differ in theory of disease causation and management. This paper presents findings on experience learned by initiation of collaboration between traditional healers and the Institute of Traditional Medicine in Arusha and Dar-es-Salaam Municipalities, Tanzania where 132 and 60 traditional healers respectively were interviewed. Of these 110 traditional healers claimed to be treating HIV/AIDS. The objective of the study was to initiate sustainable collaboration with traditional healers in managing HIV/AIDS. Consultative meetings with leaders of traditional healers' associations and government officials were held, followed by surveys at respective traditional healers' "vilinge" (traditional clinics). The findings were analysed using both qualitative and quantitative methods. The findings showed that influential people and leaders of traditional healers' association appeared to be gatekeepers to access potential good healers in the two study areas. After consultative meetings these leaders showed to be willing to collaborate; and opened doors to other traditional healers, who too were willing to collaborate with the Institute of Traditional Medicine in managing HIV/AIDS patients. Seventy five percent of traditional healers who claimed to be treating HIV/AIDS knew some HIV/AIDS symptoms; and some traditional healers attempted to manage these symptoms. Even though, they were willing to collaborate with the Institute of Traditional Medicine there were nevertheless some reservations based on questions surrounding sharing from collaboration. The reality of past experiences of mistreatment of traditional healers in the colonial period informed these reservations. General findings suggest that initiating collaboration is not as easy as it appears to be from the literature, if it is to be meaningful; and thus we are calling for appropriate strategies to access potential healers targeted for any study designed with sustainability in mind. PMID:17257409

Metrical expectations from preceding prosody influence perception of lexical stress

PubMed Central

Brown, Meredith; Salverda, Anne Pier; Dilley, Laura C.; Tanenhaus, Michael K.

2015-01-01

Two visual-world experiments tested the hypothesis that expectations based on preceding prosody influence the perception of suprasegmental cues to lexical stress. The results demonstrate that listeners’ consideration of competing alternatives with different stress patterns (e.g., ‘jury/gi’raffe) can be influenced by the fundamental frequency and syllable timing patterns across material preceding a target word. When preceding stressed syllables distal to the target word shared pitch and timing characteristics with the first syllable of the target word, pictures of alternatives with primary lexical stress on the first syllable (e.g., jury) initially attracted more looks than alternatives with unstressed initial syllables (e.g., giraffe). This effect was modulated when preceding unstressed syllables had pitch and timing characteristics similar to the initial syllable of the target word, with more looks to alternatives with unstressed initial syllables (e.g., giraffe) than to those with stressed initial syllables (e.g., jury). These findings suggest that expectations about the acoustic realization of upcoming speech include information about metrical organization and lexical stress, and that these expectations constrain the initial interpretation of suprasegmental stress cues. These distal prosody effects implicate on-line probabilistic inferences about the sources of acoustic-phonetic variation during spoken-word recognition. PMID:25621583

Shifts in global immunisation goals (1984-2004): unfinished agendas and mixed results.

PubMed

Hardon, Anita; Blume, Stuart

2005-01-01

The turn of the millennium has been marked by a large-scale mobilisation of resources for immunisation programmes in developing countries. The resources have been generated by public and private sector parties collaborating in the Global Alliance for Vaccines and Immunization (GAVI). GAVI was formed in response to deteriorating immunisation coverage rates occurring in the late 1990s. GAVI is the latest in a line of vaccine initiatives, which have operated over the past 20 years. This article reviews the five most important global immunisation initiatives that have taken place over those past 20 years. It analyses their origins, shifts in global immunisation goals, identifies key actors, assesses the initiatives' capacity to mobilise resources and increase immunisation coverage, and points to possible unintended effects of the initiatives. The study argues that shifts in global immunisation goals lead to fragmentation in the implementation of vaccine programmes at the local level in developing countries. It also suggests that global actors involved in the formulation of these initiatives appear to miss opportunities to build on past experiences and fail to learn from previous mistakes. This raises questions about the initiatives' sustainability and relevance to the overall objective of preventing vaccine-preventable deaths.

Plasma chemical conversion of sulphur hexafluoride initiated by a pulsed electron beam

NASA Astrophysics Data System (ADS)

Kholodnaya, Galina; Sazonov, Roman; Ponomarev, Denis; Guzeeva, Tatiana

2017-01-01

This paper presents the results of the experimental investigation of plasma chemical conversion of sulphur hexafluoride initiated by a pulsed electron beam (TEA-500 pulsed electron accelerator) with the following characteristics: 400-450 keV electron energy, 60 ns pulse duration, up to 200 J pulse energy, and 5 cm beam diameter. Experiments were conducted on the effect of the pulsed electron beam on SF6 and on mixtures of SF6 with O2, Ar, or N2. For the mixture of SF6 and oxygen, the results indicated chemical reactions involving the formation of a number of products of which one is sulphur, confirming the Wray - Fluorescence Analysis. The plasma chemical conversion of SF6 initiated by the pulsed electron beam was not detected when SF6 was mixed with Ar or N2, suggesting a possible mechanism for the reaction of SF6 in the presence of O2.

Competing Pathways and Multiple Folding Nuclei in a Large Multidomain Protein, Luciferase.

PubMed

Scholl, Zackary N; Yang, Weitao; Marszalek, Piotr E

2017-05-09

Proteins obtain their final functional configuration through incremental folding with many intermediate steps in the folding pathway. If known, these intermediate steps could be valuable new targets for designing therapeutics and the sequence of events could elucidate the mechanism of refolding. However, determining these intermediate steps is hardly an easy feat, and has been elusive for most proteins, especially large, multidomain proteins. Here, we effectively map part of the folding pathway for the model large multidomain protein, Luciferase, by combining single-molecule force-spectroscopy experiments and coarse-grained simulation. Single-molecule refolding experiments reveal the initial nucleation of folding while simulations corroborate these stable core structures of Luciferase, and indicate the relative propensities for each to propagate to the final folded native state. Both experimental refolding and Monte Carlo simulations of Markov state models generated from simulation reveal that Luciferase most often folds along a pathway originating from the nucleation of the N-terminal domain, and that this pathway is the least likely to form nonnative structures. We then engineer truncated variants of Luciferase whose sequences corresponded to the putative structure from simulation and we use atomic force spectroscopy to determine their unfolding and stability. These experimental results corroborate the structures predicted from the folding simulation and strongly suggest that they are intermediates along the folding pathway. Taken together, our results suggest that initial Luciferase refolding occurs along a vectorial pathway and also suggest a mechanism that chaperones may exploit to prevent misfolding. Copyright © 2017 Biophysical Society. Published by Elsevier Inc. All rights reserved.

L2 Word Recognition: Influence of L1 Orthography on Multi-syllabic Word Recognition.

PubMed

Hamada, Megumi

2017-10-01

L2 reading research suggests that L1 orthographic experience influences L2 word recognition. Nevertheless, the findings on multi-syllabic words in English are still limited despite the fact that a vast majority of words are multi-syllabic. The study investigated whether L1 orthography influences the recognition of multi-syllabic words, focusing on the position of an embedded word. The participants were Arabic ESL learners, Chinese ESL learners, and native speakers of English. The task was a word search task, in which the participants identified a target word embedded in a pseudoword at the initial, middle, or final position. The search accuracy and speed indicated that all groups showed a strong preference for the initial position. The accuracy data further indicated group differences. The Arabic group showed higher accuracy in the final than middle, while the Chinese group showed the opposite and the native speakers showed no difference between the two positions. The findings suggest that L2 multi-syllabic word recognition involves unique processes.

Spontaneous creation of the Universe Ex Nihilo

NASA Astrophysics Data System (ADS)

Lincoln, Maya; Wasser, Avi

2013-12-01

Questions regarding the formation of the Universe and ‘what was there’ before it came to existence have been of great interest to mankind at all times. Several suggestions have been presented during the ages - mostly assuming a preliminary state prior to creation. Nevertheless, theories that require initial conditions are not considered complete, since they lack an explanation of what created such conditions. We therefore propose the ‘Creatio Ex Nihilo’ (CEN) theory, aimed at describing the origin of the Universe from ‘nothing’ in information terms. The suggested framework does not require amendments to the laws of physics: but rather provides a new scenario to the Universe initiation process, and from that point merges with state-of-the-art cosmological models. The paper is aimed at providing a first step towards a more complete model of the Universe creation - proving that creation Ex Nihilo is feasible. Further adjustments, elaborations, formalisms and experiments are required to formulate and support the theory.

Ordered questions bias eyewitnesses and jurors.

PubMed

Michael, Robert B; Garry, Maryanne

2016-04-01

Eyewitnesses play an important role in the justice system. But suggestive questioning can distort eyewitness memory and confidence, and these distorted beliefs influence jurors (Loftus, Learning & Memory, 12, 361-366, 2005; Penrod & Culter, Psychology, Public Policy, and Law, 1, 817-845, 1995). Recent research, however, hints that suggestion is not necessary: Simply changing the order of a set of trivia questions altered people's beliefs about their accuracy on those questions (Weinstein & Roediger, Memory & Cognition, 38, 366-376, 2010, Memory & Cognition, 40, 727-735, 2012). We wondered to what degree eyewitnesses' beliefs-and in turn the jurors who evaluate them-would be affected by this simple change to the order in which they answer questions. Across six experiments, we show that the order of questions matters. Eyewitnesses reported higher accuracy and were more confident about their memory when questions seemed initially easy, than when they seemed initially difficult. Moreover, jurors' beliefs about eyewitnesses closely matched those of the eyewitnesses themselves. These findings have implications for eyewitness metacognition and for eyewitness questioning procedures.

Biodegradation of bis(1-chloro-2-propyl) ether via initial ether scission and subsequent dehalogenation by Rhodococcus sp. strain DTB.

PubMed

Moreno Horn, Marcus; Garbe, Leif-Alexander; Tressl, Roland; Adrian, Lorenz; Görisch, Helmut

2003-04-01

Rhodococcus sp. strain DTB (DSM 44534) grows on bis(1-chloro-2-propyl) ether (DDE) as sole source of carbon and energy. The non-chlorinated diisopropyl ether and bis(1-hydroxy-2-propyl) ether, however, did not serve as substrates. In ether degradation experiments with dense cell suspensions, 1-chloro-2-propanol and chloroacetone were formed, which indicated that scission of the ether bond is the first step while dehalogenation of the chlorinated C(3)-compounds occurs at a later stage of the degradation pathway. Inhibition of ether scission by methimazole suggested that the first step in degradation is catalyzed by a flavin-dependent enzyme activity. The non-chlorinated compounds 1,2-propanediol, hydroxyacetone, lactate, pyruvate, 1-propanol, propanal, and propionate also supported growth, which suggested that the intermediates 1,2-propanediol and hydroxyacetone are converted to pyruvate or to propionate, which can be channeled into the citric acid cycle by a number of routes. Total release of chloride and growth-yield experiments with DDE and non-chlorinated C(3)-compounds suggested complete biodegradation of the chlorinated ether.

Looking the part (to me): effects of racial prototypicality on race perception vary by prejudice.

PubMed

Cassidy, Brittany S; Sprout, Gregory T; Freeman, Jonathan B; Krendl, Anne C

2017-04-01

Less racially prototypic faces elicit more category competition during race categorization. Top-down factors (e.g. stereotypes), however, affect categorizations, suggesting racial prototypicality may enhance category competition in certain perceivers. Here, we examined how prejudice affects race category competition and stabilization when perceiving faces varying in racial prototypicality. Prototypically low vs high Black relative to White faces elicited more category competition and slower response latencies during categorization (Experiment 1), suggesting a pronounced racial prototypicality effect on minority race categorization. However, prejudice predicted the extent of category competition between prototypically low vs high Black faces. Suggesting more response conflict toward less prototypic Black vs White faces, anterior cingulate cortex activity increased toward Black vs White faces as they decreased in racial prototypicality, with prejudice positively predicting this difference (Experiment 2). These findings extend the literature on racial prototypicality and categorization by showing that relative prejudice tempers the extent of category competition and response conflict engaged when initially perceiving faces. © The Author (2017). Published by Oxford University Press. For Permissions, please email: journals.permissions@oup.com.

Experience-dependent escalation of glucose drinking and the development of glucose preference over fructose - association with glucose entry into the brain.

PubMed

Wakabayashi, Ken T; Spekterman, Laurence; Kiyatkin, Eugene A

2016-06-01

Glucose, a primary metabolic substrate for cellular activity, must be delivered to the brain for normal neural functions. Glucose is also a unique reinforcer; in addition to its rewarding sensory properties and metabolic effects, which all natural sugars have, glucose crosses the blood-brain barrier and acts on glucoreceptors expressed on multiple brain cells. To clarify the role of this direct glucose action in the brain, we compared the neural and behavioural effects of glucose with those induced by fructose, a sweeter yet metabolically equivalent sugar. First, by using enzyme-based biosensors in freely moving rats, we confirmed that glucose rapidly increased in the nucleus accumbens in a dose-dependent manner after its intravenous delivery. In contrast, fructose induced a minimal response only after a large-dose injection. Second, we showed that naive rats during unrestricted access consumed larger volumes of glucose than fructose solution; the difference appeared with a definite latency during the initial exposure and strongly increased during subsequent tests. When rats with equal sugar experience were presented with either glucose or fructose in alternating order, the consumption of both substances was initially equal, but only the consumption of glucose increased during subsequent sessions. Finally, rats with equal glucose-fructose experience developed a strong preference for glucose over fructose during a two-bottle choice procedure; the effect appeared with a definite latency during the initial test and greatly amplified during subsequent tests. Our results suggest that direct entry of glucose in the brain and its subsequent effects on brain cells could be critical for the experience-dependent escalation of glucose consumption and the development of glucose preference over fructose. Published 2015. This article is a U.S. Government work and is in the public domain in the USA.

The role of answer fluency and perceptual fluency as metacognitive cues for initiating analytic thinking.

PubMed

Thompson, Valerie A; Turner, Jamie A Prowse; Pennycook, Gordon; Ball, Linden J; Brack, Hannah; Ophir, Yael; Ackerman, Rakefet

2013-08-01

Although widely studied in other domains, relatively little is known about the metacognitive processes that monitor and control behaviour during reasoning and decision-making. In this paper, we examined the conditions under which two fluency cues are used to monitor initial reasoning: answer fluency, or the speed with which the initial, intuitive answer is produced (Thompson, Prowse Turner, & Pennycook, 2011), and perceptual fluency, or the ease with which problems can be read (Alter, Oppenheimer, Epley, & Eyre, 2007). The first two experiments demonstrated that answer fluency reliably predicted Feeling of Rightness (FOR) judgments to conditional inferences and base rate problems, which subsequently predicted the amount of deliberate processing as measured by thinking time and answer changes; answer fluency also predicted retrospective confidence judgments (Experiment 3b). Moreover, the effect of answer fluency on reasoning was independent from the effect of perceptual fluency, establishing that these are empirically independent constructs. In five experiments with a variety of reasoning problems similar to those of Alter et al. (2007), we found no effect of perceptual fluency on FOR, retrospective confidence or accuracy; however, we did observe that participants spent more time thinking about hard to read stimuli, although this additional time did not result in answer changes. In our final two experiments, we found that perceptual disfluency increased accuracy on the CRT (Frederick, 2005), but only amongst participants of high cognitive ability. As Alter et al.'s samples were gathered from prestigious universities, collectively, the data to this point suggest that perceptual fluency prompts additional processing in general, but this processing may results in higher accuracy only for the most cognitively able. Crown Copyright © 2012. Published by Elsevier B.V. All rights reserved.

Gaze behaviour during space perception and spatial decision making.

PubMed

Wiener, Jan M; Hölscher, Christoph; Büchner, Simon; Konieczny, Lars

2012-11-01

A series of four experiments investigating gaze behavior and decision making in the context of wayfinding is reported. Participants were presented with screenshots of choice points taken in large virtual environments. Each screenshot depicted alternative path options. In Experiment 1, participants had to decide between them to find an object hidden in the environment. In Experiment 2, participants were first informed about which path option to take as if following a guided route. Subsequently, they were presented with the same images in random order and had to indicate which path option they chose during initial exposure. In Experiment 1, we demonstrate (1) that participants have a tendency to choose the path option that featured the longer line of sight, and (2) a robust gaze bias towards the eventually chosen path option. In Experiment 2, systematic differences in gaze behavior towards the alternative path options between encoding and decoding were observed. Based on data from Experiments 1 and 2 and two control experiments ensuring that fixation patterns were specific to the spatial tasks, we develop a tentative model of gaze behavior during wayfinding decision making suggesting that particular attention was paid to image areas depicting changes in the local geometry of the environments such as corners, openings, and occlusions. Together, the results suggest that gaze during a wayfinding tasks is directed toward, and can be predicted by, a subset of environmental features and that gaze bias effects are a general phenomenon of visual decision making.

Managing money matters: Managing finances is associated with functional independence in MCI.

PubMed

Berezuk, Courtney; Ramirez, Joel; Black, Sandra E; Zakzanis, Konstantine K

2018-03-01

Previous research suggests that overall experience participating in instrumental activities of daily living (IADLs) is associated with reduced IADL impairment in individuals with mild cognitive impairment, possibly because of an increased functional reserve. Given that difficulties managing finances tend to occur with mild cognitive impairment, this study explores whether experience managing one's finances is associated with independence across various IADLs. Participants with a screen or baseline diagnosis of mild cognitive impairment (n = 862) were taken from the Alzheimer's Disease Neuroimaging Initiative study. Functional dependence and experience were quantified from the Functional Activities Questionnaire. No group differences between those with and without financial management experience existed in Mini-Mental State Examination scores, age, and years of education, although women were more likely to have experience managing finances (P < .001). Final chi-square analyses suggest that financial management experience is significantly associated with greater independence in the ability to follow TV, books, or magazines (P = .009) and remember appointments and important dates (P = .002). Individuals who are rated as having experience in managing their finances were also rated as being less dependent in their ability to follow and understand TV and books and in their ability to remember appointments and important dates. Neither causation nor the mechanisms underlying this relationship can be discerned from these analyses. Therefore, further research is needed to investigate whether engaging in financial tasks protects against early financial impairment, potentially through an increased functional reserve. Copyright © 2017 John Wiley & Sons, Ltd.

Identifying sensitive areas of adaptive observations for prediction of the Kuroshio large meander using a shallow-water model

NASA Astrophysics Data System (ADS)

Zou, Guang'an; Wang, Qiang; Mu, Mu

2016-09-01

Sensitive areas for prediction of the Kuroshio large meander using a 1.5-layer, shallow-water ocean model were investigated using the conditional nonlinear optimal perturbation (CNOP) and first singular vector (FSV) methods. A series of sensitivity experiments were designed to test the sensitivity of sensitive areas within the numerical model. The following results were obtained: (1) the eff ect of initial CNOP and FSV patterns in their sensitive areas is greater than that of the same patterns in randomly selected areas, with the eff ect of the initial CNOP patterns in CNOP sensitive areas being the greatest; (2) both CNOP- and FSV-type initial errors grow more quickly than random errors; (3) the eff ect of random errors superimposed on the sensitive areas is greater than that of random errors introduced into randomly selected areas, and initial errors in the CNOP sensitive areas have greater eff ects on final forecasts. These results reveal that the sensitive areas determined using the CNOP are more sensitive than those of FSV and other randomly selected areas. In addition, ideal hindcasting experiments were conducted to examine the validity of the sensitive areas. The results indicate that reduction (or elimination) of CNOP-type errors in CNOP sensitive areas at the initial time has a greater forecast benefit than the reduction (or elimination) of FSV-type errors in FSV sensitive areas. These results suggest that the CNOP method is suitable for determining sensitive areas in the prediction of the Kuroshio large-meander path.

Peer learning partnerships: exploring the experience of pre-registration nursing students.

PubMed

Christiansen, Angela; Bell, Amelia

2010-03-01

This paper explores the impact of a peer learning initiative developed to facilitate, purposefully, mutually supportive learning relationships between student nurses in the practice setting. Finding effective strategies to support learning in the practice setting has been the focus of professional concern for a considerable time. In the UK clinical mentorship is seen as pivotal to ensuring fitness to practice; however, recent debate on the nature of learning has revealed the clinical workplace as a rich learning environment where learning occurs not only through hierarchical relationships, but also from a network of peer relationships. Formalising peer relationships through peer assisted learning is increasingly suggested as a strategy to support workplace learning and support novice students' transition to the clinical setting. Despite the developing literature in this field there is limited understanding about how students experience facilitated peer relationships. An interpretive qualitative design. Focus group interviews were used to collect interactive and situated discourse from nursing students who had recently participated in peer learning partnerships (n = 54). Narrative data were analysed thematically. Findings suggest that active support from a fellow student reduced the feelings of social isolation experienced by novice students in initial clinical placements, helping them to deal more effectively with the challenges faced and reducing the factors that have an impact on attrition. In addition, the reciprocity of the peer learning partnerships facilitated understanding of mentorship and created a heightened sense of readiness for registration and professional practice. Peer learning partnerships facilitated by mentors in clinical practice can support the transition to nursing for first year students and can help more experienced students gain a confidence and a heightened readiness for mentorship and registered practice. Facilitated peer learning partnerships can enhance the student experience in the practice setting and can help maximise opportunities for learning and support. This suggests that peer assisted learning is a legitimate area for innovation and further research.

Determination of oxidant exposure during ozonation of secondary effluent to predict contaminant removal.

PubMed

Zucker, Ines; Avisar, Dror; Mamane, Hadas; Jekel, Martin; Hübner, Uwe

2016-09-01

The use of kinetic models to predict oxidation performance in wastewater is limited due to fast ozone depletion during the first milliseconds of the reaction. This paper introduces the Quench Flow Module (QFM), a bench-scale experimental technique developed to measure the first 5-500 milliseconds of ozone depletion for accurate determination of ozone exposure in wastewater-ozonation processes. Calculated ozone exposure in QFM experiments was up to 24% lower than in standard batch experiments, strongly depending on the initial sampling point for measurement in batch experiments. However, oxidation rates of slowly- and moderately-reacting trace organic compounds (TrOCs) were accurately predicted from batch experiments based on integration of ozone depletion and removal of an ozone-resistant probe compound to calculate oxidant exposures. An alternative concept, where ozone and hydroxyl radical exposures are back-calculated from the removal of two probe compounds, was tested as well. Although the QFM was suggested to be an efficient mixing reactor, ozone exposure ranged over three orders of magnitude when different probe compounds reacting moderately with ozone were used for the calculation. These effects were beyond uncertainty ranges for apparent second order rate constants and consistently observed with different ozone-injection techniques, i.e. QFM, batch experiments, bubble columns and venturi injection. This indicates that previously suggested mixing effects are not responsible for the difference and other still unknown factors might be relevant. Results furthermore suggest that ozone exposure calculations from the relative residual concentration of a probe compound are not a promising option for evaluation of ozonation of secondary effluents. Copyright © 2016 Elsevier Ltd. All rights reserved.

To Explore the Experiences of Women on Reasons in Initiating and Maintaining Breastfeeding in Urban Area of Karachi, Pakistan: An Exploratory Study

PubMed Central

Shaheen Premani, Zahra; Kurji, Zohra; Mithani, Yasmin

2011-01-01

This is an exploratory study that explores the experiences of lactating women in initiating, continuing, or discontinuing breastfeeding in an urban area of Karachi, Pakistan. Objectives. To explore the experiences of lactating women and to understand their support and hindering mechanisms in initiating and maintaining breastfeeding. Methods. This is an exploratory design assisting in exploring the participant's experiences of initiating and maintaining breastfeeding to better understand their world. Purposive sampling was used, and data was analyzed through manual thematic analysis. Results. The data revealed that mother's knowledge, sociocultural environment, breastfeeding decision, and self- and professional support acted as driving forces for the participants. However, sociocultural environment, physiological changes, time management, and being a housewife to breastfeed their children were all challenges and barriers that the participants thought hindered their breastfeeding initiation and maintenance. Conclusion. Breastfeeding is a natural but taxing phenomenon, and breastfeeding mothers experience supporting and hindering factors in initiating and maintaining breastfeeding. PMID:22389780

Learning clinical skills in the simulation suite: the lived experiences of student nurses involved in peer teaching and peer assessment.

PubMed

Ramm, Dianne; Thomson, Anna; Jackson, Andrew

2015-06-01

The benefits of peer teaching and assessment are well documented within nurse education literature. However, research to date has predominantly focused on the advantages and disadvantages for the inexperienced learner, with a dearth of knowledge relating to the perceptions of senior nursing students involved in teaching their peers. This study sought to investigate the student experience of taking part in a peer teaching and assessment initiative to include the perceptions of both first year nursing students and second/third year participants. Data were collected via open-ended questionnaires and analysed with qualitative 'Framework' analysis. This initiative received a generally positive response both from students being taught and also from those acting as facilitators. Perceived benefits included the social learning experience, development of teaching skills, self-awareness and the opportunity to communicate both good and bad news. Suggestions for improvement included additional time working in small groups, specific supplementary learning materials and the introduction of peer teaching and assessment into other areas of the Adult Nursing Programme. Peer teaching and assessment principles represent valuable strategies which can be utilised in nurse education to develop clinical skills and prepare nurses for real-life scenarios. Further research needs to investigate how to enhance the student learning experience and to fully exploit the potential for simulated experience to prepare students for their future role as registered nurses in clinical practice. Copyright © 2015 Elsevier Ltd. All rights reserved.

First Plasma Results from the Levitated Dipole Experiment

NASA Astrophysics Data System (ADS)

Garnier, Darren T.

2005-04-01

On August 13, 2004, the first plasma physics experiments were conducted using the Levitated Dipole Experiment(LDX)http://www.psfc.mit.edu/ldx/. LDX was built at MIT's Plasma Science and Fusion Center as a joint research project of Columbia University and MIT. LDX is a first-of-its-kind experiment incorporating three superconducting magnets and exploring the physics of high-temperature plasma confined by dipole magnetic fields, similar to planetary magnetospheres. It will test recent theories that suggest that stable, high-β plasma can be confined without good curvature or magnetic shear, instead using plasma compressibility to provide stability. (Plasma β is the ratio of plasma pressure to magnetic pressure.) In initial experiments, 750 kA of current was induced in the dipole coil which was physically supported in the center of the 5 m diameter vacuum chamber. Deuterium plasma discharges, lasting from 4 to 10 seconds, were formed with multi-frequency ECRH microwave heating of up to 6.2 kW. Each plasma contained a large fraction of energetic and relativistic electrons that created a significant pressure that caused outward expansion of the magnetic field. Reconstruction of the magnetic equilibrium from external magnetic diagnostics indicate local peak plasma β 7 %. Along with an overview of the LDX device, results from numerous diagnostics operating during this initial supported campaign measuring the basic plasma parameters will be presented. In addition, observations of instabilities leading to rapid plasma loss and the effects of changing plasma compressibility will be explored.

Ceiling art in a radiation therapy department: its effect on patient treatment experience

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

Bonett, Jotham

A new initiative has been implemented at the Sunshine Hospital Radiation Therapy Centre, to provide a calming and comforting environment for patients attending radiation therapy treatment. As part of this initiative, the department's computed tomography (CT) room and radiation therapy bunkers were designed to incorporate ceiling art that replicates a number of different visual scenes. The study was undertaken to determine if ceiling art in the radiation therapy treatment CT and treatment bunkers had an effect on a patient's experience during treatment at the department. Additionally, the study aimed to identify which of the visuals in the ceiling art weremore » most preferred by patients. Patients were requested to complete a 12-question survey. The survey solicited a patient's opinion/perception on the unit's unique ceiling display with emphasis on aesthetic appeal, patient treatment experience and the patient's engagement due to the ceiling display. The responses were dichotomised to ‘positive’ or ‘negative’. Every sixth patient who completed the survey was invited to have a general face-to-face discussion to provide further information about their thoughts on the displays. The results demonstrate that the ceiling artwork solicited a positive reaction in 89.8% of patients surveyed. This score indicates that ceiling artwork contributed positively to patients’ experiences during radiation therapy treatment. The study suggests that ceiling artwork in the department has a positive effect on patient experience during their radiation therapy treatment at the department.« less

Sox2 is translationally activated by eukaryotic initiation factor 4E in human glioma-initiating cells

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

Ge, Yuqing; Zhou, Fengbiao; Chen, Hong

2010-07-09

Sox2, a master transcription factor, contributes to the generation of induced pluripotent stem cells and plays significant roles in sustaining the self-renewal of neural stem cells and glioma-initiating cells. Understanding the functional differences of Sox2 between glioma-initiating cells and normal neural stem cells would contribute to therapeutic approach for treatment of brain tumors. Here, we first demonstrated that Sox2 could contribute to the self-renewal and proliferation of glioma-initiating cells. The following experiments showed that Sox2 was activated at translational level in a subset of human glioma-initiating cells compared with the normal neural stem cells. Further investigation revealed there was amore » positive correlation between Sox2 and eukaryotic initiation factor 4E (eIF4E) in glioma tissues. Down-regulation of eIF4E decreased Sox2 protein level without altering its mRNA level in glioma-initiating cells, indicating that Sox2 was activated by eIF4E at translational level. Furthermore, eIF4E was presumed to regulate the expression of Sox2 by its 5' untranslated region (5' UTR) sequence. Our results suggest that the eIF4E-Sox2 axis is a novel mechanism of unregulated self-renewal of glioma-initiating cells, providing a potential therapeutic target for glioma.« less

A novel mechanism for Bcr-Abl action: Bcr-Abl-mediated induction of the eIF4F translation initiation complex and mRNA translation.

PubMed

Prabhu, S; Saadat, D; Zhang, M; Halbur, L; Fruehauf, J P; Ong, S T

2007-02-22

The oncogenic kinase Bcr-Abl is thought to cause chronic myelogenous leukemia (CML) by altering the transcription of specific genes with growth- and survival-promoting functions. Recently, Bcr-Abl has also been shown to activate an important regulator of protein synthesis, the mammalian target of rapamycin (mTOR), which suggests that dysregulated translation may also contribute to CML pathogenesis. In this study, we found that both Bcr-Abl and the rapamycin-sensitive mTORC1 complex contribute to the phosphorylation (inactivation) of 4E-BP1, an inhibitor of the eIF4E translation initiation factor. Experiments with rapamycin and the Bcr-Abl inhibitor, imatinib mesylate, in Bcr-Abl-expressing cell lines and primary CML cells indicated that Bcr-Abl and mTORC1 induced formation of the translation initiation complex, eIF4F. This was characterized by reduced 4E-BP1 binding and increased eIF4G binding to eIF4E, two events that lead to the assembly of eIF4F. One target transcript is cyclin D3, which is regulated in Bcr-Abl-expressing cells by both Bcr-Abl and mTORC1 in a translational manner. In addition, the combination of imatinib and rapamycin was found to act synergistically against committed CML progenitors from chronic and blast phase patients. These experiments establish a novel mechanism of action for Bcr-Abl, and they provide insights into the modes of action of imatinib mesylate and rapamycin in treatment of CML. They also suggest that aberrant cap-dependent mRNA translation may be a therapeutic target in Bcr-Abl-driven malignancies.

Under the (legal) radar screen: global health initiatives and international human rights obligations.

PubMed

Hammonds, Rachel; Ooms, Gorik; Vandenhole, Wouter

2012-11-15

Given that many low income countries are heavily reliant on external assistance to fund their health sectors the acceptance of obligations of international assistance and cooperation with regard to the right to health (global health obligations) is insufficiently understood and studied by international health and human rights scholars. Over the past decade Global Health Initiatives, like the Global Fund to fight AIDS, Tuberculosis and Malaria (Global Fund) have adopted novel approaches to engaging with stakeholders in high and low income countries. This article explores how this experience impacted on acceptance of the international obligation to (help) fulfil the right to health beyond borders. The authors conducted an extensive review of international human rights law literature, transnational legal process literature, global public health literature and grey literature pertaining to Global Health Initiatives. To complement this desk work and deepen their understanding of how and why different legal norms evolve the authors conducted 19 in-depth key informant interviews with actors engaged with three stakeholders; the European Union, the United States and Belgium. The authors then analysed the interviews through a transnational legal process lens. Through according value to the process of examining how and why different legal norms evolve transnational legal process offers us a tool for engaging with the dynamism of developments in global health suggesting that operationalising global health obligations could advance the right to health for all. In many low-income countries the health sector is heavily dependent on external assistance to fulfil the right to health of people thus it is vital that policies and tools for delivering reliable, long-term assistance are developed so that the right to health for all becomes more than a dream. Our research suggests that the Global Fund experience offers lessons to build on.

Initiation and Modification of Reaction by Energy Addition: Kinetic and Transport Phenomena

DTIC Science & Technology

1990-10-01

ignition- delay time ranges from about 2 to 100 ps. The results of a computer- modeling calcu- lation of the chemical kinetics suggest that the...Page PROGRAM INFORMATION iii 1.0 RESEARCH OBJECTIVES 2.0 ANALYSIS 2 3.0 EXPERIMENT 7 REFERENCES 8 APPENDIX I. Evaluating a Simple Model for Laminar...Flame-Propagation I-1 Rates. I. Planar Geometry. APPENDIX II. Evaluating a Simple Model for Laminar-Flame-Propagation II-1 Rates. II. Spherical

Chemical Reactions in Turbulent Mixing Flows

DTIC Science & Technology

1990-11-15

our preliminary experiments suggest that for the range 20,000 < Re < 100.000 the flame length , at fixed stoichiometric mixture ratio, is decreasing...used to identify any changes in the slope of the initial section, the location of the knee which can serve as a definition of flame length , as well...be good. The mixture fraction is nearly the same in the two reactors at x/do = 50, which is nearly the flame length . The agreement aside, it is

The effect of cathodic polarization on the corrosion fatigue behavior of a precipitation hardened aluminum alloy

NASA Astrophysics Data System (ADS)

Smith, E. F.; Duquette, D. J.

1986-02-01

Fatigue experiments were conducted on polycrystalline and monocrystalline samples of a high purity Al, 5.5 wt pct Zn, 2.5 wt pct Mg, 1.5 wt pct Cu alloy in the peak-hardened heat treatment condition. These experiments were conducted in dry laboratory air and in 0.5 N NaCl solutions at the corrosion potential and at applied potentials cathodic to the corrosion potential. It has been shown that saline solutions severely reduce the fatigue resistance of the alloy, resulting in considerable amounts of intergranular crack initiation and propagation under freely corroding conditions for polycrystalline samples. Applied cathodic potentials resulted in still larger decreases in fatigue resistance and, for poly crystals, increases in the degree of transgranular crack initiation and propagation. Increasing amounts of intergranular cracking were observed when applied cyclic stresses were reduced (longer test times). The characteristics of cracking, combined with results obtained on tensile tests of deformed and hydrogen charged samples, suggest that environmental cracking of these alloys is associated with a form of hydrogen embrittlement of the process zones of growing cracks. Further, it is suggested that stress corrosion cracking and corrosion fatigue of these alloys occurs by essentially the same mechanism, but that the often observed transgranular cracking under cyclic loading conditions occurs due to enhanced hydrogen transport and/or concentrations associated with mobile dislocations at growing crack tips.

Organic haze on Titan and the early Earth

PubMed Central

Trainer, Melissa G.; Pavlov, Alexander A.; DeWitt, H. Langley; Jimenez, Jose L.; McKay, Christopher P.; Toon, Owen B.; Tolbert, Margaret A.

2006-01-01

Recent exploration by the Cassini/Huygens mission has stimulated a great deal of interest in Saturn's moon, Titan. One of Titan's most captivating features is the thick organic haze layer surrounding the moon, believed to be formed from photochemistry high in the CH4/N2 atmosphere. It has been suggested that a similar haze layer may have formed on the early Earth. Here we report laboratory experiments that demonstrate the properties of haze likely to form through photochemistry on Titan and early Earth. We have used a deuterium lamp to initiate particle production in these simulated atmospheres from UV photolysis. Using a unique analysis technique, the aerosol mass spectrometer, we have studied the chemical composition, size, and shape of the particles produced as a function of initial trace gas composition. Our results show that the aerosols produced in the laboratory can serve as analogs for the observed haze in Titan's atmosphere. Experiments performed under possible conditions for early Earth suggest a significant optical depth of haze may have dominated the early Earth's atmosphere. Aerosol size measurements are presented, and implications for the haze layer properties are discussed. We estimate that aerosol production on the early Earth may have been on the order of 1014 g·year−1 and thus could have served as a primary source of organic material to the surface. PMID:17101962

Global and local concerns: what attitudes and beliefs motivate farmers to mitigate and adapt to climate change?

PubMed

Haden, Van R; Niles, Meredith T; Lubell, Mark; Perlman, Joshua; Jackson, Louise E

2012-01-01

In response to agriculture's vulnerability and contribution to climate change, many governments are developing initiatives that promote the adoption of mitigation and adaptation practices among farmers. Since most climate policies affecting agriculture rely on voluntary efforts by individual farmers, success requires a sound understanding of the factors that motivate farmers to change practices. Recent evidence suggests that past experience with the effects of climate change and the psychological distance associated with people's concern for global and local impacts can influence environmental behavior. Here we surveyed farmers in a representative rural county in California's Central Valley to examine how their intention to adopt mitigation and adaptation practices is influenced by previous climate experiences and their global and local concerns about climate change. Perceived changes in water availability had significant effects on farmers' intention to adopt mitigation and adaptation strategies, which were mediated through global and local concerns respectively. This suggests that mitigation is largely motivated by psychologically distant concerns and beliefs about climate change, while adaptation is driven by psychologically proximate concerns for local impacts. This match between attitudes and behaviors according to the psychological distance at which they are cognitively construed indicates that policy and outreach initiatives may benefit by framing climate impacts and behavioral goals concordantly; either in a global context for mitigation or a local context for adaptation.

Testing effects in mixed- versus pure-list designs.

PubMed

Rowland, Christopher A; Littrell-Baez, Megan K; Sensenig, Amanda E; DeLosh, Edward L

2014-08-01

In the present study, we investigated the role of list composition in the testing effect. Across three experiments, participants learned items through study and initial testing or study and restudy. List composition was manipulated, such that tested and restudied items appeared either intermixed in the same lists (mixed lists) or in separate lists (pure lists). In Experiment 1, half of the participants received mixed lists and half received pure lists. In Experiment 2, all participants were given both mixed and pure lists. Experiment 3 followed Erlebacher's (Psychological Bulletin, 84, 212-219, 1977) method, such that mixed lists, pure tested lists, and pure restudied lists were given to independent groups. Across all three experiments, the final recall results revealed significant testing effects for both mixed and pure lists, with no reliable difference in the magnitude of the testing advantage across list designs. This finding suggests that the testing effect is not subject to a key boundary condition-list design-that impacts other memory phenomena, including the generation effect.

Face Experience and the Attentional Bias for Fearful Expressions in 6- and 9-Month-Old Infants

PubMed Central

Safar, Kristina; Kusec, Andrea; Moulson, Margaret C.

2017-01-01

Infants demonstrate an attentional bias toward fearful facial expressions that emerges in the first year of life. The current study investigated whether this attentional bias is influenced by experience with particular face types. Six-month-old (n = 33) and 9-month-old (n = 31) Caucasian infants' spontaneous preference for fearful facial expressions when expressed by own-race (Caucasian) or other-race (East Asian) faces was examined. Six-month-old infants showed a preference for fearful expressions when expressed by own-race faces, but not when expressed by other-race faces. Nine-month-old infants showed a preference for fearful expressions when expressed by both own-race faces and other-race faces. These results suggest that how infants deploy their attention to different emotional expressions is shaped by experience: Attentional biases might initially be restricted to faces with which infants have the most experience, and later be extended to faces with which they have less experience. PMID:28979221

Effect of imbalanced nutrients and immigration on Prymnesium parvum community dominance and toxicity: Results from in-lake microcosm experiments

USGS Publications Warehouse

Errera, R.M.; Roelke, D.L.; Kiesling, R.L.; Brooks, B.W.; Grover, J.P.; Schwierzke, L.; Urena-Boeck, F.; Baker, J.W.; Pinckney, J.L.

2008-01-01

Prymnesium parvum, a haptophyte species, forms harmful blooms, including those that have caused severe fish kills in Texas, USA, over the past 6 yr. We studied P. parvum dynamics using in situ microcosm experiments at Lake Possum Kingdom, Texas, during 3 seasons (fall 2004, winter and spring 2005). Experimental treatments included full and partial nutrient enrichment (encompassing nitrogen [N] and phosphorus [P] deficient treatments), P. parvum immigration and combinations of these factors. In the control and N and P deficient treatments, P. parvum populations dominated the community, but only in the N deficient treatments did P. parvum experience a significant growth in the population. In contrast, when nutrients were not limiting, P. parvum tended to lose its competitive edge to other taxa such as chlorophytes, euglenophytes and diatoms, which then dominated the community. Population growth of P. parvum was also stimulated through immigration, but only during the winter experiment, a period of the year when bloom initiation is common. This finding suggests that movement into the water column may be an important process leading to P. parvum bloom initiation. Toxicity of P. parvum to fish was also affected by the nutrient changes: during conditions of no nutrient addition P. parvum was most toxic; intermediate toxicity was observed under N and P deficient conditions, and full nutrient enrichments resulted in nearly non-toxic conditions. ?? Inter-Research 2008.

"Hopefully This Will All Make Sense at Some Point": Meaning and Performance in Illness Blogs.

PubMed

Heilferty, Catherine McGeehin

To analyze the narratives of illness blogs created by parents of children with cancer. The profound effects of the childhood cancer experience on family members and the turn to the Internet by parents for help in the process are gaining research attention. The qualitative study design involved secondary narrative analysis of 14 illness blogs: 9 by the parents of children with neuroblastoma and 5 by the parents of children with leukemia. Daily blog entries were analyzed as individual units of illness experience expression and in relation to one another to identify thematic and linguistic similarities. The initial analysis of these illness blogs resulted in identification of the quest for balance as a primary theme. Narratives in parents' childhood cancer illness blogs illustrated themes of performance. During this initial analysis, however, the author repeatedly asked, "Why are they writing this? And why publish this?" A second analysis of the data answered these questions of why parents blog about the experience. Narrative analysis resulted in the discovery of 6 main reasons that parents wrote and published the childhood cancer experience online: to report, explain, express, reflect, archive, and advocate. The analysis suggests that incorporation of parent writing may improve family--provider communication, enhance the family-health care professional relationship, enhance safety by preventing medical errors, improve reporting of clinical trial data such as adverse events, and improve satisfaction.

FGF signaling induces mesoderm in the hemichordate Saccoglossus kowalevskii

PubMed Central

Green, Stephen A.; Norris, Rachael P.; Terasaki, Mark; Lowe, Christopher J.

2013-01-01

FGFs act in vertebrate mesoderm induction and also play key roles in early mesoderm formation in ascidians and amphioxus. However, in sea urchins initial characterizations of FGF function do not support a role in early mesoderm induction, making the ancestral roles of FGF signaling and mechanisms of mesoderm specification in deuterostomes unclear. In order to better characterize the evolution of mesoderm formation, we have examined the role of FGF signaling during mesoderm development in Saccoglossus kowalevskii, an experimentally tractable representative of hemichordates. We report the expression of an FGF ligand, fgf8/17/18, in ectoderm overlying sites of mesoderm specification within the archenteron endomesoderm. Embryological experiments demonstrate that mesoderm induction in the archenteron requires contact with ectoderm, and loss-of-function experiments indicate that both FGF ligand and receptor are necessary for mesoderm specification. fgf8/17/18 gain-of-function experiments establish that FGF8/17/18 is sufficient to induce mesoderm in adjacent endomesoderm. These experiments suggest that FGF signaling is necessary from the earliest stages of mesoderm specification and is required for all mesoderm development. Furthermore, they suggest that the archenteron is competent to form mesoderm or endoderm, and that FGF signaling from the ectoderm defines the location and amount of mesoderm. When considered in a comparative context, these data support a phylogenetically broad requirement for FGF8/17/18 signaling in mesoderm specification and suggest that FGF signaling played an ancestral role in deuterostome mesoderm formation. PMID:23344709

Escaping affect: how motivated emotion regulation creates insensitivity to mass suffering.

PubMed

Cameron, C Daryl; Payne, B Keith

2011-01-01

As the number of people in need of help increases, the degree of compassion people feel for them ironically tends to decrease. This phenomenon is termed the collapse of compassion. Some researchers have suggested that this effect happens because emotions are not triggered by aggregates. We provide evidence for an alternative account. People expect the needs of large groups to be potentially overwhelming, and, as a result, they engage in emotion regulation to prevent themselves from experiencing overwhelming levels of emotion. Because groups are more likely than individuals to elicit emotion regulation, people feel less for groups than for individuals. In Experiment 1, participants displayed the collapse of compassion only when they expected to be asked to donate money to the victims. This suggests that the effect is motivated by self-interest. Experiment 2 showed that the collapse of compassion emerged only for people who were skilled at emotion regulation. In Experiment 3, we manipulated emotion regulation. Participants who were told to down-regulate their emotions showed the collapse of compassion, but participants who were told to experience their emotions did not. We examined the time course of these effects using a dynamic rating to measure affective responses in real time. The time course data suggested that participants regulate emotion toward groups proactively, by preventing themselves from ever experiencing as much emotion toward groups as toward individuals. These findings provide initial evidence that motivated emotion regulation drives insensitivity to mass suffering. (PsycINFO Database Record (c) 2010 APA, all rights reserved).

An initial experience with hip resurfacing versus cementless total hip arthroplasty.

PubMed

Arndt, Justin Michael; Wera, Glenn D; Goldberg, Victor M

2013-07-01

Hip resurfacing is an alternative to total hip arthroplasty. We aimed to compare an experienced hip surgeon's initial clinical results of hip resurfacing with a new cementless total hip arthroplasty (THA). The first 55 consecutive hip resurfacing arthroplasties were compared to 100 consecutive cementless THAs using a cylindrical tapered femoral stem. The learning curve between the two procedures was compared utilizing the incidence of reoperation, complications, Harris Hip Scores (HHS), and implant survivorship. The reoperation rate was significantly higher (p = 0.019) for hip resurfacing (14.5%) versus THA (4%). The overall complication rate between the two groups was not significantly different (p = 0.398). Preoperative HHS were similar between the two groups (p = 0.2). The final mean HHS was similar in both the resurfacing and THA groups (96 vs. 98.3, respectively, p < 0.65). Kaplan-Meier survival analysis with an endpoint of reoperation suggests complications occurred earlier in the resurfacing group versus the THA group (log-rank test, p = 0.007). In comparison to our initial experience with a cementless THA stem, operative complications occur earlier and more often after hip resurfacing during the learning period. The clinical outcomes in both groups however are similar at 5 year follow-up.

Empirical evaluation of inhibitory product, substrate, and enzyme effects during the enzymatic saccharification of lignocellulosic biomass.

PubMed

Smith, Benjamin T; Knutsen, Jeffrey S; Davis, Robert H

2010-05-01

The cellulose hydrolysis kinetics during batch enzymatic saccharification are typified by a rapid initial rate that subsequently decays, resulting in incomplete conversion. Previous studies suggest that changes associated with the solution, substrate, or enzymes may be responsible. In this work, kinetic experiments were conducted to determine the relative magnitude of these effects. Pretreated corn stover (PCS) was used as a lignocellulosic substrate likely to be found in a commercial saccharification process, while Avicel and Kraft lignin were used to create model substrates. Glucose inhibition was observed by spiking the reaction slurry with glucose during initial-rate experiments. Increasing the glucose concentration from 7 to 48 g/L reduced the cellulose conversion rate by 94%. When product sugars were removed using ultrafiltration with a 10 kDa membrane, the glucose-based conversion increased by 9.5%. Reductions in substrate reactivity with conversion were compared directly by saccharifying PCS and Avicel substrates that had been pre-reacted to different conversions. Reaction of substrate with a pre-conversion of 40% resulted in about 40% reduction in the initial rate of saccharification, relative to fresh substrate with identical cellulose concentration. Overall, glucose inhibition and reduced substrate reactivity appear to be dominant factors, whereas minimal reductions of enzyme activity were observed.

Analysis and experiments for composite laminates with holes and subjected to 4-point bending

NASA Technical Reports Server (NTRS)

Shuart, M. J.; Prasad, C. B.

1990-01-01

Analytical and experimental results are presented for composite laminates with a hole and subjected to four-point bending. A finite-plate analysis is used to predict moment and strain distributions for six-layer quasi-isotropic laminates and transverse-ply laminates. Experimental data are compared with the analytical results. Experimental and analytical strain results show good agreement for the quasi-isotropic laminates. Failure of the two types of composite laminates is described, and failure strain results are presented as a function of normalized hole diameter. The failure results suggest that the initial failure mechanism for laminates subjected to four-point bending are similar to the initial failure mechanisms for corresponding laminates subjected to uniaxial inplane loadings.

New insights into the interplay between the translation machinery and nonsense-mediated mRNA decay factors.

PubMed

Raimondeau, Etienne; Bufton, Joshua C; Schaffitzel, Christiane

2018-06-19

Faulty mRNAs with a premature stop codon (PTC) are recognized and degraded by nonsense-mediated mRNA decay (NMD). Recognition of a nonsense mRNA depends on translation and on the presence of NMD-enhancing or the absence of NMD-inhibiting factors in the 3'-untranslated region. Our review summarizes our current understanding of the molecular function of the conserved NMD factors UPF3B and UPF1, and of the anti-NMD factor Poly(A)-binding protein, and their interactions with ribosomes translating PTC-containing mRNAs. Our recent discovery that UPF3B interferes with human translation termination and enhances ribosome dissociation in vitro , whereas UPF1 is inactive in these assays, suggests a re-interpretation of previous experiments and modification of prevalent NMD models. Moreover, we discuss recent work suggesting new functions of the key NMD factor UPF1 in ribosome recycling, inhibition of translation re-initiation and nascent chain ubiquitylation. These new findings suggest that the interplay of UPF proteins with the translation machinery is more intricate than previously appreciated, and that this interplay quality-controls the efficiency of termination, ribosome recycling and translation re-initiation. © 2018 The Author(s).

Creating beauty: creativity compensates for low physical attractiveness when individuals assess the attractiveness of social and romantic partners.

PubMed

Watkins, Christopher D

2017-04-01

Although creativity is attractive in a potential mate, it is unclear (i) whether the effects of creativity on attractiveness generalize to other social contexts and (ii) whether creativity has equivalent effects on men's and women's attractiveness. As social knowledge of creativity may either enhance or 'offset' the appeal of social partners who differ in physical attractiveness, three repeated measures experiments were conducted to directly address these issues. Here, participants rated a series of face-text pairs for attractiveness on trials that differed in one of four combinations of facial attractiveness (attractive and less attractive) and creativity (creative and less creative), rating story-tellers in two experiments (short interpretations of an identical painting) and creative ideas in a further experiment (alternative uses for an everyday object). Regardless of the sex of the judge, creativity and facial attractiveness had independent effects on men's overall attractiveness (initial experiment) and, in further experiments, more substantial effects on the attractiveness of men with less attractive faces than men with attractive faces (when using a different measure of creativity) and specific effects on the attractiveness of individuals with less attractive faces (when using different face stimuli). Collectively, across three experiments, these findings suggest that creativity may compensate for putative cues to lower biological 'quality' and that the benefits of creativity to social groups more generally enhance attraction to creative men (in two experiments) and creative men and women (one experiment). More broadly, the data suggest that species can integrate knowledge of cognitive intelligence with visual cues to biological 'quality' to facilitate mate and/or ally choice.

Experimental investigation on the initial expansion stage of vacuum arc on cup-shaped TMF contacts

NASA Astrophysics Data System (ADS)

Wang, Ting; Xiu, Shixin; Liu, Zixi; Zhang, Yanzhe; Feng, Dingyu

2018-02-01

Arc behavior and measures to control it directly affect the properties of vacuum circuit breakers. Nowadays, transverse magnetic field (TMF) contacts are widely used for medium voltages. A magnetic field perpendicular to the current direction between the TMF contacts makes the arc move, transmitting its energy to the whole contact and avoiding excessive local ablation. Previous research on TMF arc behavior concentrated mainly on the arc movement and less on the initial stage (from arc ignition to an unstable arc column). A significant amount of experiment results suggest that there is a short period of arc stagnation after ignition. The duration of this arc stagnation and the arc characteristics during this stage affect the subsequent arc motion and even the breaking property of interrupters. The present study is of the arc characteristics in the initial stage. Experiments were carried out in a demountable vacuum chamber with cup-shaped TMF contacts. Using a high-speed camera, both single-point arc ignition mode and multiple-point arc ignition (MPAI) mode were observed. The experimental data show that the probability of MPAI mode occurring is related to the arc current. The influences of arc-ignition mode, arc current, and contact diameter on the initial expansion process were investigated. In addition, simulations were performed to analyze the multiple arc expansion process mechanically. Based on the experimental phenomena and simulation results, the mechanism of the arc expansion motion was analyzed.

Congestion of mastoid mucosa and influence on middle ear pressure - Effect of retroauricular injection of adrenaline.

PubMed

Fooken Jensen, Pernille Vita; Gaihede, Michael

2016-10-01

Micro-CT scanning of temporal bones has revealed numerous retroauricular microchannels, which connect the outer bone surface directly to the underlying mastoid air cells. Their structure and dimensions have suggested a separate vascular supply to the mastoid mucosa, which may play a role in middle ear (ME) pressure regulation. This role may be accomplished by changes in the mucosa congestion resulting in volumetric changes, which ultimately affect the pressure of the enclosed ME gas pocket (Boyle's law). Further, such mucosa congestion may be susceptible to α-adrenergic stimulation similar to the mucosa of the nose. The purpose of our study was to investigate these hypotheses by recording the ME pressure in response to adrenergic stimulation administered by retroauricular injections at the surface of the microchannels. In a group of 20 healthy adults we measured the ME pressure by tympanometry initially in the sitting position, and then in the supine position over a 5 min period with 30 s intervals. In each subject, the study included 1) a control reference experiment with no intervention, 2) a control experiment with subcutaneously retroauricular injection of 1 ml isotonic NaCl solution, and 3) a test experiment with subcutaneously retroauricular injection of 1 ml NaCl-adrenaline solution. In both control experiments the ME pressure displayed an immediate increase in response to changing body position; this pressure increase remained stable for the entire period up to five minutes. In the test experiments the ME pressure also showed an initial pressure increase, but it was followed by a distinct significant pressure decrease with a maximum after 90 s. The test group was injected with both a 5 and 10% adrenaline solution, but the responses appeared similar for the two concentrations. Subcutaneous retroauricular injection of adrenaline caused a significant pressure decrease in ME pressure compared with control ears. This may be explained by the microchannels conveying the adrenaline to the underlying mastoid mucosa, where it may result in a vascular constriction and decongestion, ultimately resulting in a ME pressure decrease. These findings suggest that the microchannels contain vascular connections to the mastoid mucosa, and that the mastoid mucosa is susceptible to vasoactive mediators, which may play a role in ME pressure regulation. Further anatomical and physiological experiments should be carried out to confirm these suggestions including pharmacological interactions with the mastoid mucosa. Copyright © 2016 Elsevier B.V. All rights reserved.

Positive Technology for Healthy Living and Active Ageing.

PubMed

Riva, Giuseppe; Gaggioli, Andrea; Villani, Daniela; Cipresso, Pietro; Repetto, Claudia; Serino, Silvia; Triberti, Stefano; Brivio, Eleonora; Galimberti, Carlo; Graffigna, Guendalina

2014-01-01

Information and communication technologies are widely and rapidly spreading in people's daily lives. But what is the possible role of the mass proliferation of digital devices in supporting healthy living and active ageing? Are they useful in fostering personal growth and individual integration of the elderly, by promoting satisfaction, opportunities for action, and self-expression? Rather, do they enhance automation, impose constraints on personal initiative, and result in compulsive consumption of information? In this chapter, we suggest that possible answers to these questions will be offered by the "Positive Technology" approach, i.e., the scientific and applied approach to using technology so that it improves the quality of our personal experiences through its structuring, augmentation, and/or replacement. First, we suggest that it is possible to use technology to manipulate the quality of experience with the goal of increasing wellness and generating strengths and resilience in individuals, organizations, and society. Then, we classify positive technologies according to their effects on these three features of personal experience - Hedonic: technologies used to induce positive and pleasant experiences; Eudaimonic: technologies used to support individuals in reaching engaging and self-actualizing experiences; Social/Interpersonal: technologies used to support and improve the connectedness between individuals, groups, and organizations. Finally, we discuss the possible role of positive technologies for healthy living and active ageing by presenting different practical applications of this approach.

Role of defects in laser-induced modifications of silica coatings and fused silica using picosecond pulses at 1053 nm: II Scaling laws and the density of precursors

DOE PAGES

Laurence, T. A.; Negres, R. A.; Ly, S.; ...

2017-06-22

Here, we investigate the role of defects in laser-induced damage of fused silica and of silica coatings produced by e-beam and PIAD processes which are used in damage resistant, multi-layer dielectric, reflective optics. We perform experiments using 1053 nm, 1–60 ps laser pulses with varying beam size, number of shots, and pulse widths in order to understand the characteristics of defects leading to laser-induced damage. This pulse width range spans a transition in mechanisms from intrinsic material ablation for short pulses to defect-dominated damage for longer pulses. We show that for pulse widths as short as 10 ps, laser-induced damagemore » properties of fused silica and silica films are dominated by isolated absorbers. The density of these precursors and their fluence dependence of damage initiation suggest a single photon process for initial energy absorption in these precursors. Higher density precursors that initiate close to the ablation threshold at shorter pulse widths are also observed in fused silica, whose fluence and pulse width scaling suggest a multiphoton initiation process. We also show that these initiated damage sites grow with subsequent laser pulses. We show that scaling laws obtained in more conventional ways depend on the beam size and on the definition of damage for ps pulses. For this reason, coupling scaling laws with the density of precursors are critical to understanding the damage limitations of optics in the ps regime.« less

Role of defects in laser-induced modifications of silica coatings and fused silica using picosecond pulses at 1053 nm: II Scaling laws and the density of precursors

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

Laurence, T. A.; Negres, R. A.; Ly, S.

Here, we investigate the role of defects in laser-induced damage of fused silica and of silica coatings produced by e-beam and PIAD processes which are used in damage resistant, multi-layer dielectric, reflective optics. We perform experiments using 1053 nm, 1–60 ps laser pulses with varying beam size, number of shots, and pulse widths in order to understand the characteristics of defects leading to laser-induced damage. This pulse width range spans a transition in mechanisms from intrinsic material ablation for short pulses to defect-dominated damage for longer pulses. We show that for pulse widths as short as 10 ps, laser-induced damagemore » properties of fused silica and silica films are dominated by isolated absorbers. The density of these precursors and their fluence dependence of damage initiation suggest a single photon process for initial energy absorption in these precursors. Higher density precursors that initiate close to the ablation threshold at shorter pulse widths are also observed in fused silica, whose fluence and pulse width scaling suggest a multiphoton initiation process. We also show that these initiated damage sites grow with subsequent laser pulses. We show that scaling laws obtained in more conventional ways depend on the beam size and on the definition of damage for ps pulses. For this reason, coupling scaling laws with the density of precursors are critical to understanding the damage limitations of optics in the ps regime.« less

Parallel analysis of tagged deletion mutants efficiently identifies genes involved in endoplasmic reticulum biogenesis.

PubMed

Wright, Robin; Parrish, Mark L; Cadera, Emily; Larson, Lynnelle; Matson, Clinton K; Garrett-Engele, Philip; Armour, Chris; Lum, Pek Yee; Shoemaker, Daniel D

2003-07-30

Increased levels of HMG-CoA reductase induce cell type- and isozyme-specific proliferation of the endoplasmic reticulum. In yeast, the ER proliferations induced by Hmg1p consist of nuclear-associated stacks of smooth ER membranes known as karmellae. To identify genes required for karmellae assembly, we compared the composition of populations of homozygous diploid S. cerevisiae deletion mutants following 20 generations of growth with and without karmellae. Using an initial population of 1,557 deletion mutants, 120 potential mutants were identified as a result of three independent experiments. Each experiment produced a largely non-overlapping set of potential mutants, suggesting that differences in specific growth conditions could be used to maximize the comprehensiveness of similar parallel analysis screens. Only two genes, UBC7 and YAL011W, were identified in all three experiments. Subsequent analysis of individual mutant strains confirmed that each experiment was identifying valid mutations, based on the mutant's sensitivity to elevated HMG-CoA reductase and inability to assemble normal karmellae. The largest class of HMG-CoA reductase-sensitive mutations was a subset of genes that are involved in chromatin structure and transcriptional regulation, suggesting that karmellae assembly requires changes in transcription or that the presence of karmellae may interfere with normal transcriptional regulation. Copyright 2003 John Wiley & Sons, Ltd.

Initial performance of the radio occultation experiment in the Venus orbiter mission Akatsuki

NASA Astrophysics Data System (ADS)

Imamura, Takeshi; Ando, Hiroki; Tellmann, Silvia; Pätzold, Martin; Häusler, Bernd; Yamazaki, Atsushi; Sato, Takao M.; Noguchi, Katsuyuki; Futaana, Yoshifumi; Oschlisniok, Janusz; Limaye, Sanjay; Choudhary, R. K.; Murata, Yasuhiro; Takeuchi, Hiroshi; Hirose, Chikako; Ichikawa, Tsutomu; Toda, Tomoaki; Tomiki, Atsushi; Abe, Takumi; Yamamoto, Zen-ichi; Noda, Hirotomo; Iwata, Takahiro; Murakami, Shin-ya; Satoh, Takehiko; Fukuhara, Tetsuya; Ogohara, Kazunori; Sugiyama, Ko-ichiro; Kashimura, Hiroki; Ohtsuki, Shoko; Takagi, Seiko; Yamamoto, Yukio; Hirata, Naru; Hashimoto, George L.; Yamada, Manabu; Suzuki, Makoto; Ishii, Nobuaki; Hayashiyama, Tomoko; Lee, Yeon Joo; Nakamura, Masato

2017-10-01

After the arrival of Akatsuki spacecraft of Japan Aerospace Exploration Agency at Venus in December 2015, the radio occultation experiment, termed RS (Radio Science), obtained 19 vertical profiles of the Venusian atmosphere by April 2017. An onboard ultra-stable oscillator is used to generate stable X-band downlink signals needed for the experiment. The quantities to be retrieved are the atmospheric pressure, the temperature, the sulfuric acid vapor mixing ratio, and the electron density. Temperature profiles were successfully obtained down to 38 km altitude and show distinct atmospheric structures depending on the altitude. The overall structure is close to the previous observations, suggesting a remarkable stability of the thermal structure. Local time-dependent features are seen within and above the clouds, which is located around 48-70 km altitude. The H2SO4 vapor density roughly follows the saturation curve at cloud heights, suggesting equilibrium with cloud particles. The ionospheric electron density profiles are also successfully retrieved, showing distinct local time dependence. Akatsuki RS mainly probes the low and middle latitude regions thanks to the near-equatorial orbit in contrast to the previous radio occultation experiments using polar orbiters. Studies based on combined analyses of RS and optical imaging data are ongoing.[Figure not available: see fulltext.

Following instructions from working memory: Why does action at encoding and recall help?

PubMed

Jaroslawska, Agnieszka J; Gathercole, Susan E; Allen, Richard J; Holmes, Joni

2016-11-01

Two experiments investigated the consequences of action at encoding and recall on the ability to follow sequences of instructions. Children ages 7-9 years recalled sequences of spoken action commands under presentation and recall conditions that either did or did not involve their physical performance. In both experiments, recall was enhanced by carrying out the instructions as they were being initially presented and also by performing them at recall. In contrast, the accuracy of instruction-following did not improve above spoken presentation alone, either when the instructions were silently read or heard by the child (Experiment 1), or when the child repeated the spoken instructions as they were presented (Experiment 2). These findings suggest that the enactment advantage at presentation does not simply reflect a general benefit of a dual exposure to instructions, and that it is not a result of their self-production at presentation. The benefits of action-based recall were reduced following enactment during presentation, suggesting that the positive effects of action at encoding and recall may have a common origin. It is proposed that the benefits of physical movement arise from the existence of a short-term motor store that maintains the temporal, spatial, and motoric features of either planned or already executed actions.

Effect of initial moisture content on the in-vessel composting under air pressure of organic fraction of municipal solid waste in Morocco

PubMed Central

2013-01-01

This study aimed to evaluate the effect of initial moisture content on the in-vessel composting under air pressure of organic fraction of municipal solid waste in Morocco in terms of internal temperature, produced gases quantity, organic matter conversion rate, and the quality of the final composts. For this purpose, in-vessel bioreactor was designed and used to evaluate both appropriate initial air pressure and appropriate initial moisture content for the composting process. Moreover, 5 experiments were carried out within initial moisture content of 55%, 65%, 70%, 75% and 85%. The initial air pressure and the initial moisture content of the mixture showed a significant effect on the aerobic composting. The experimental results demonstrated that for composting organic waste, relatively high moisture contents are better at achieving higher temperatures and retaining them for longer times. This study suggested that an initial moisture content of around 75%, under 0.6 bar, can be considered as being suitable for efficient composting of organic fraction of municipal solid waste. These last conditions, allowed maximum value of temperature and final composting product with good physicochemical properties as well as higher organic matter degradation and higher gas production. Moreover, final compost obtained showed good maturity levels and can be used for agricultural applications. PMID:23369502

Bitter taste and nicotine preference: evidence for sex differences in rats.

PubMed

Nesil, Tanseli; Kanit, Lutfiye; Pogun, Sakire

2015-01-01

Nicotine affects sensory pathways and an interaction between taste and nicotine preference is likely. In addition to pharmacologic effects, orosensory factors are important in nicotine dependence. Recent evidence suggests a link between taste (notably bitter) receptor genes and nicotine addiction. To explore the possible interaction between taste and nicotine preference in rats, including sex as a factor. Adult male and female Sprague Dawley rats (n = 82) were used in free choice oral intake experiments. In Experiment 1 rats received water from one bottle and one of the taste substances (quinine, sucrose, or saccharine) from the other bottle for 12 days. Following a wash-out period, Experiment 2a was initiated in the same rats. Rats received water from one bottle and nicotine (10 and 20 mg/l) from the other for 12 days. In Experiment 2b, nicotine exposure was continued for four more weeks. Liquid intake and weight were measured at four-day (Experiments 1 and 2a) and one week (Experiment 2b) periods. In female rats, quinine and subsequent nicotine intake were positively correlated and quinine intake and weight gain were negatively correlated. No association was depicted between nicotine consumption and sweet tastants in either female or male animals. The results suggest that bitter taste and nicotine preference are related, but only in female rats. This finding is parallel to observations in human smokers. Our study may be a preliminary step in the search for common genes that underlie nicotine dependence and taste preference.

Differential effects of removing the glucose or saccharin components of a glucose-saccharin mixture in a successive negative contrast paradigm.

PubMed

Mitchell, Colin P; Flaherty, Charles F

2005-03-31

When rats experience an unexpected decrease in reward value, e.g., from 32% sucrose to 4% sucrose, consummatory behavior abruptly decreases to a level below control subjects that only experience the lesser reward, a phenomenon known as Successive Negative Contrast (SNC). In food deprived rats experiencing downshifts in sucrose concentration, SNC dissipates in 3-4 days, as consummatory behavior in shifted rats recovers to the level of unshifted controls. In Experiment 1 food deprived rats that were given 5 min daily access to a 2% glucose-0.15% saccharin mixture, and subsequently shifted to 2% glucose alone, displayed a dramatic SNC effect relative to rats that only received 2% glucose. This SNC effect was primarily manifested as a decrease in the number of consummatory bursts initiated. Interestingly, intake failed to recover to control levels during eight daily postshift sessions. However, in Experiment 2 subjects that were shifted from the same glucose-saccharin mixture to 0.15% saccharin alone failed to show SNC rather, intake fell to the level of control animals which only received 0.15% saccharin. The data from Experiment 1, in conjunction with previous studies utilizing non-deprived rats, quinine adulteration, or shifts from sucrose to saccharin, show that reductions in taste value can produce contrast effects, but suggest that a threshold caloric value is necessary for recovery. The data from Experiment 2 may suggest that saccharin and glucose do not contribute equally to the enhanced palatability of the mixture.

Removal of trace organic chemicals in onsite wastewater soil treatment units: a laboratory experiment.

PubMed

Teerlink, Jennifer; Martínez-Hernández, Virtudes; Higgins, Christopher P; Drewes, Jörg E

2012-10-15

Onsite wastewater treatment is used by 20% of residences in the United States. The ability of these systems, specifically soil treatment units (STUs), to attenuate trace organic chemicals (TOrCs) is not well understood. TOrCs released by STUs pose a potential risk to downstream groundwater and hydraulically-connected surface water that may be used as a drinking water source. A series of bench-scale experiments were conducted using sand columns to represent STUs and to evaluate the efficacy of TOrC attenuation as a function of hydraulic loading rate (1, 4, 8, 12, and 30 cm/day). Each hydraulic loading rate was examined using triplicate experimental columns. Columns were initially seeded with raw wastewater to establish a microbial community, after which they were fed with synthetic wastewater and spiked with 17 TOrCs, in four equal doses per day, to provide a consistent influent water quality. After an initial start-up phase, effluent from all columns consistently demonstrated >90% reductions in dissolved organic carbon and nearly complete (>85%) oxidation of ammonia to nitrate, comparable to the performance of field STUs. The results of this study suggest STUs are capable of attenuating many TOrCs present in domestic wastewater, but attenuation is compound-specific. A subset of TOrCs exhibited an inverse relationship with hydraulic loading rate and attenuation efficiency. Atenolol, cimetidine, and TCPP were more effectively attenuated over time in each experiment, suggesting that the microbial community evolved to a stage where these TOrCs were more effectively biotransformed. Aerobic conditions as compared to anaerobic conditions resulted in more efficient attenuation of acetaminophen and cimetidine. Copyright © 2012. Published by Elsevier Ltd.

[Evaluation of the influence of humidity and temperature on the drug stability by initial average rate experiment].

PubMed

He, Ning; Sun, Hechun; Dai, Miaomiao

2014-05-01

To evaluate the influence of temperature and humidity on the drug stability by initial average rate experiment, and to obtained the kinetic parameters. The effect of concentration error, drug degradation extent, humidity and temperature numbers, humidity and temperature range, and average humidity and temperature on the accuracy and precision of kinetic parameters in the initial average rate experiment was explored. The stability of vitamin C, as a solid state model, was investigated by an initial average rate experiment. Under the same experimental conditions, the kinetic parameters obtained from this proposed method were comparable to those from classical isothermal experiment at constant humidity. The estimates were more accurate and precise by controlling the extent of drug degradation, changing humidity and temperature range, or by setting the average temperature closer to room temperature. Compared with isothermal experiments at constant humidity, our proposed method saves time, labor, and materials.

A magnetic pulse does not affect homing pigeon navigation: a GPS tracking experiment.

PubMed

Holland, Richard; Filannino, Caterina; Gagliardo, Anna

2013-06-15

The cues by which homing pigeons are able to return to a home loft after displacement to unfamiliar release sites remain debated. A number of experiments in which migratory birds have been treated with a magnetic pulse have produced a disruption in their orientation, which argues that a ferrimagnetic sense is used for navigation in birds. One previous experiment has also indicated an effect of magnetic pulses on homing pigeon navigation, although with inconsistent results. Previous studies have shown that some magnetic-related information is transmitted by the trigeminal nerve to the brain in some bird species, including the homing pigeon. The function of this information is still unclear. It has been suggested that this information is important for navigation. Previous studies with trigeminal nerve lesioned homing pigeons have clearly shown that the lack of trigeminally mediated information, even if magnetic, is not crucial for homing performance. However, this result does not completely exclude the possibility that other ferrimagnetic receptors in the homing pigeon play a role in navigation. Additionally, recent studies on homing pigeons suggested the existence of a ferrimagnetic sense in a novel location presumably located in the inner ear (lagena). In the present study, we tested whether any ferrimagnetic magnetoreceptors, irrespective of their location in the bird's head, are involved in pigeons' homing. To do this, we treated homing pigeons with a strong magnetic pulse before release, tracked birds with GPS loggers and analyzed whether this treatment affected homing performance. In the single previous magnetic pulse experiment on homing pigeons, only initial orientation at a release site was considered and the results were inconsistent. We observed no effect of the magnetic pulse at any of the sites used on initial orientation, homing performance, tortuosity or track efficiency, which does not support a role for the ferrimagnetic sense in homing pigeon navigation, at least not in this geographic area, where magnetic field variations are in the region of 200 nT intensity and 0.8 deg inclination.

Persistent overconfidence despite practice: the role of task experience in preschoolers' recall predictions.

PubMed

Lipko, Amanda R; Dunlosky, John; Merriman, William E

2009-06-01

In three experiments, preschoolers' ability to predict their picture recall was examined. Children studied 10 pictures, predicted how many they would recall, and then attempted to recall them. This study-prediction-recall trial was repeated multiple times with new pictures on each trial. In Experiment 1, children were overconfident on the initial trial, and this overconfidence persisted across three trials. In Experiment 2, children predicted either their own performance or another child's performance. Their predictions were overconfident across all trials regardless of whether they made predictions for themselves or for another child, suggesting that wishful thinking cannot fully account for their overconfidence. In Experiment 3, some children postdicted their previous recall performance prior to making each prediction. Although their postdictions were quite accurate, their predictions were still overconfident across five trials. Preschoolers' overconfidence was remarkably resistant to the repeated experience of recalling fewer pictures than the children had predicted. Even asking them to report the number that they recalled on a previous trial, which they could do accurately, did not cause them to lower their predictions across trials.

Effects of NOx on the volatility of secondary organic aerosol from isoprene photooxidation

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

Xu, Lu; Kollman, Matthew S.; Song, Chen

2014-01-28

The effects of NOx on the volatility of the secondary organic aerosol (SOA) formed from isoprene photooxidation are investigated in environmental chamber experiments. Two types of experiments are performed. In HO2-dominant experiments, organic peroxy radicals (RO2) primarily react with HO2. In mixed experiments, RO2 reacts through multiple pathways. The volatility and oxidation state of isoprene SOA is sensitive to and displays a non-linear dependence on NOx levels. When initial NO/isoprene ratio is approximately 3 (ppbv:ppbv), SOA are shown to be most oxidized and least volatile, associated with the highest SOA yield. A High-Resolution Time-of-Flight Aerosol Mass Spectrometer (HR-ToF-AMS) is appliedmore » to characterize the key chemical properties of aerosols. While the composition of SOA in mixed experiments does not change substantially over time, SOA become less volatile and more oxidized as oxidation progresses in HO2-dominant experiments. Analysis of the SOA composition suggests that the further reactions of organic peroxides and alcohols may produce carboxylic acids, which might play a strong role in SOA aging.« less

Experience-driven plasticity in binocular vision

PubMed Central

Klink, P. Christiaan; Brascamp, Jan W.; Blake, Randolph; van Wezel, Richard J.A.

2010-01-01

Summary Experience-driven neuronal plasticity allows the brain to adapt its functional connectivity to recent sensory input. Here we use binocular rivalry [1], an experimental paradigm where conflicting images are presented to the individual eyes, to demonstrate plasticity in the neuronal mechanisms that convert visual information from two separated retinas into single perceptual experiences. Perception during binocular rivalry tended to initially consist of alternations between exclusive representations of monocularly defined images, but upon prolonged exposure, mixture percepts became more prevalent. The completeness of suppression, reflected in the incidence of mixture percepts, plausibly reflects the strength of inhibition that likely plays a role in binocular rivalry [2]. Recovery of exclusivity was possible, but required highly specific binocular stimulation. Documenting the prerequisites for these observed changes in perceptual exclusivity, our experiments suggest experience-driven plasticity at interocular inhibitory synapses, driven by the (lack of) correlated activity of neurons representing the conflicting stimuli. This form of plasticity is consistent with a previously proposed, but largely untested, anti-Hebbian learning mechanism for inhibitory synapses in vision [3, 4]. Our results implicate experience-driven plasticity as one governing principle in the neuronal organization of binocular vision. PMID:20674360

The impact of secondary-task type on the sensitivity of reaction-time based measurement of cognitive load for novices learning surgical skills using simulation.

PubMed

Rojas, David; Haji, Faizal; Shewaga, Rob; Kapralos, Bill; Dubrowski, Adam

2014-01-01

Interest in the measurement of cognitive load (CL) in simulation-based education has grown in recent years. In this paper we present two pilot experiments comparing the sensitivity of two reaction time based secondary task measures of CL. The results suggest that simple reaction time measures are sensitive enough to detect changes in CL experienced by novice learners in the initial stages of simulation-based surgical skills training.

An antivirally active sulfated polysaccharide from Sargassum horneri (TURNER) C. AGARDH.

PubMed

Hoshino, T; Hayashi, T; Hayashi, K; Hamada, J; Lee, J B; Sankawa, U

1998-07-01

A sulfated polysaccharide was isolated from the hot water extract of a brown alga, Sargassum horneri (TURNER) C. AGARDH. Fucose was detected as the main component sugar of this polysaccharide. This compound showed potent antiviral activity against herpes simplex virus type 1, human cytomegalovirus and human immunodeficiency virus type 1. Time-of-addition experiments suggested that it inhibited not only the initial stages of viral infection, such as attachment to and penetration into host cells, but also later replication stages after virus penetration.

Adrenal hormones and the anorectic response and adaptation of rats to amino acid imbalance.

PubMed

Hammer, V A; Gietzen, D W; Sworts, V D; Beverly, J L; Rogers, Q R

1990-12-01

The role of adrenal function in the anorectic response and adaptation of rats to a diet with an isoleucine (Ile) imbalance was investigated. In the first of four experiments, rats were fed a mildly Ile-imbalanced diet after treatment with metyrapone, and inhibitor of glucocorticoid synthesis. In two separate experiments, rats were presented with either a mildly or severely Ile-imbalanced diet (4.93 and 9.86% imbalanced amino acid mixture, respectively) after bilateral adrenalectomy. Finally, the effects of ICS 205-930, a serotonin-3 receptor antagonist, on the intake of mildly Ile-imbalanced diet were tested in adrenalectomized animals. In each experiment a 2 X 2 factorial design was used. Neither metyrapone nor adrenalectomy altered the initial depression in the intake of an imbalanced diet. The adaptation phase in the response of adrenalectomized rats fed a mildly Ile-imbalanced diet was not different from that of controls, but adrenalectomized rats fed severely Ile-imbalanced diets were unable to adapt. Adrenalectomy did not alter the anti-anoretic activity of ICS 205-930 in this model. These results suggest that adrenal hormones are not necessary for the initial anoretic response or adaptation of rats to an Ile-imbalanced diet, nor are they implicated in the anti-anorectic effect of serotonin-3 blockade.

Contextualizing neuro-collaborations: reflections on a transdisciplinary fMRI lie detection experiment

PubMed Central

Littlefield, Melissa M.; Fitzgerald, Des; Knudsen, Kasper; Tonks, James; Dietz, Martin J.

2014-01-01

Recent neuroscience initiatives (including the E.U.’s Human Brain Project and the U.S.’s BRAIN Initiative) have reinvigorated discussions about the possibilities for transdisciplinary collaboration between the neurosciences, the social sciences, and the humanities. As STS scholars have argued for decades, however, such inter- and transdisciplinary collaborations are potentially fraught with tensions between researchers. This essay build on such claims by arguing that the tensions of transdisciplinary research also exist within researchers’ own experiences of working between disciplines - a phenomenon that we call “disciplinary double consciousness” (DDC). Building on previous work that has characterized similar spaces (and especially on the Critical Neuroscience literature), we argue that “neuro-collaborations” inevitably engage researchers in DDC - a phenomenon that allows us to explore the useful dissonance that researchers can experience when working between a “home” discipline and a secondary discipline. Our case study is a five-year research project in functional magnetic resonance imaging (fMRI) lie detection involving a transdisciplinary research team made up of social scientists, a neuroscientist, and a humanist. In addition to theorizing neuro-collaborations from the inside-out, this essay presents practical suggestions for developing transdisciplinary infrastructures that could support future neuro-collaborations. PMID:24744713

Developmental evaluation and the 'Stronger Economies Together' initiative in the United States.

PubMed

Honadle, Beth Walter; Zapata, Marisa A; Auffrey, Christopher; vom Hofe, Rainer; Looye, Johanna

2014-04-01

This article describes a developmental evaluation and explains its impact on the Stronger Economies Together (SET) initiative of the U.S. Department of Agriculture in collaboration with the Nation's four Regional Rural Development Centers and Land-Grant universities. Through a dynamic process, this evaluation of the early phases of an initiative led to continuous program alterations based on feedback. The relationship of the evaluation team to the initiative's coordinating team enabled seamless transfer of observations, suggestions, and recommendations to decision makers. The multidisciplinary character of the evaluation team provided a diverse set of perspectives with a depth of subject matter and knowledge from relevant fields. One lesson is that developmental evaluators must be flexible, nimble, creative, and adaptive. When expected data are imperfect or nonexistent, the team must collect alternate information and make recommendations to improve data collection. As the initiative proceeded and modifications came about, the evaluation team had to recognize the changes in the program and focus on different questions. This experience with developmental evaluation provides insights into how interdisciplinary teams may need to change course and conduct a developmental evaluation when a formative evaluation was originally envisioned. Published by Elsevier Ltd.

Knowledgeable Lemurs Become More Central in Social Networks.

PubMed

Kulahci, Ipek G; Ghazanfar, Asif A; Rubenstein, Daniel I

2018-04-23

Strong relationships exist between social connections and information transmission [1-9], where individuals' network position plays a key role in whether or not they acquire novel information [2, 3, 5, 6]. The relationships between social connections and information acquisition may be bidirectional if learning novel information, in addition to being influenced by it, influences network position. Individuals who acquire information quickly and use it frequently may receive more affiliative behaviors [10, 11] and may thus have a central network position. However, the potential influence of learning on network centrality has not been theoretically or empirically addressed. To bridge this epistemic gap, we investigated whether ring-tailed lemurs' (Lemur catta) centrality in affiliation networks changed after they learned how to solve a novel foraging task. Lemurs who had frequently initiated interactions and approached conspecifics before the learning experiment were more likely to observe and learn the task solution. Comparing social networks before and after the learning experiment revealed that the frequently observed lemurs received more affiliative behaviors than they did before-they became more central after the experiment. This change persisted even after the task was removed and was not caused by the observed lemurs initiating more affiliative behaviors. Consequently, quantifying received and initiated interactions separately provides unique insights into the relationships between learning and centrality. While the factors that influence network position are not fully understood, our results suggest that individual differences in learning and becoming successful can play a major role in social centrality, especially when learning from others is advantageous. Copyright © 2018 Elsevier Ltd. All rights reserved.

Videothoracoscopy in the treatment of spontaneous pneumothorax: an initial experience.

PubMed Central

Waller, D. A.; Yoruk, Y.; Morritt, G. N.; Forty, J.; Dark, J. H.

1993-01-01

We report an initial experience with the new and potentially advantageous technique of videothoracoscopy in the treatment of pneumothorax. A series of 18 consecutive patients (14 male, 4 female) presenting with spontaneous pneumothorax over a 4-month period underwent surgical treatment by this method. The indication for surgery was recurrent pneumothorax in nine patients and persistent air leak in the remainder (median duration 15 days, range 5-28 days). Stapled apical bullectomy with apical parietal pleurectomy was performed in 14 patients, bullectomy alone was performed in one patient and pleurectomy alone in three patients. Additional talc pleurodesis was carried out in three of these patients. Median duration of operation was 53.5 min (range 35-120 min). The median postoperative drainage was 300 ml in 24 h (range 50-580 ml). The median duration of intercostal drainage was 48 h (range 24-384 h) and of postoperative hospital stay 4 days (range 3-18 days). The mean postoperative analgesic requirement was 1.3 mg morphine/h. Three complications required reoperation. In two patients a large air leak persisted after operation; one proceeded to thoracotomy for suturing of the air leak and in the other this was accomplished by videothoracoscopy. A further patient re-presented at 2 weeks with recurrent pneumothorax which was treated at thoracotomy. At a median follow-up of 68.5 days (range 10-124 days) this is the only recurrence. These complications were caused by errors in surgical technique early in our series. This initial experience of videothoracoscopic pleurectomy suggests it is an effective, well-tolerated treatment of spontaneous pneumothorax. PMID:8379623

HIV care and treatment experiences among female sex workers living with HIV in sub-Saharan Africa: A systematic review.

PubMed

Lancaster, Kathryn E; Cernigliaro, Dana; Zulliger, Rose; Fleming, Paul F

2016-12-01

Female sex workers (FSW) living with HIV in sub-Saharan Africa have poor engagement to HIV care and treatment. Understanding the HIV care and treatment engagement experiences of FSW has important implications for interventions to enhance care and treatment outcomes. We conducted a systematic review to examine the HIV care experiences and determinants of linkage and retention in care, antiretroviral therapy (ART) initiation, and ART adherence and viral suppression among FSW living with HIV in sub-Saharan Africa. The databases PubMed, Embase, Web of Science, SCOPUS, CINAHL, Global Health, Psycinfo, Sociological Abstracts, and Popline were searched for variations of search terms related to sex work and HIV care and treatment among sub-Saharan African populations. Ten peer-reviewed articles published between January 2000 and August 2015 met inclusion criteria and were included in this review. Despite expanded ART access, FSW in sub-Saharan Africa have sub-optimal HIV care and treatment engagement outcomes. Stigma, discrimination, poor nutrition, food insecurity, and substance use were commonly reported and associated with poor linkage to care, retention in care, and ART initiation. Included studies suggest that interventions with FSW should focus on multilevel barriers to engagement in HIV care and treatment and explore the involvement of social support from intimate male partners. Our results emphasise several critical points of intervention for FSW living with HIV, which are urgently needed to enhance linkage to HIV care, retention in care, and treatment initiation, particularly where the HIV prevalence among FSW is greatest.

Investigation of particle and vapor wall-loss effects on controlled wood-smoke smog-chamber experiments

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

Bian, Q.; May, A. A.; Kreidenweis, Sonia M.

Here, smog chambers are extensively used to study processes that drive gas and particle evolution in the atmosphere. A limitation of these experiments is that particles and gas-phase species may be lost to chamber walls on shorter timescales than the timescales of the atmospheric processes being studied in the chamber experiments. These particle and vapor wall losses have been investigated in recent studies of secondary organic aerosol (SOA) formation, but they have not been systematically investigated in experiments of primary emissions from combustion. The semi-volatile nature of combustion emissions (e.g. from wood smoke) may complicate the behavior of particle andmore » vapor wall deposition in the chamber over the course of the experiments due to the competition between gas/particle and gas/wall partitioning. Losses of vapors to the walls may impact particle evaporation in these experiments, and potential precursors for SOA formation from combustion may be lost to the walls, causing underestimations of aerosol yields. Here, we conduct simulations to determine how particle and gas-phase wall losses contributed to the observed evolution of the aerosol during experiments in the third Fire Lab At Missoula Experiment (FLAME III). We use the TwO-Moment Aerosol Sectional (TOMAS) microphysics algorithm coupled with the organic volatility basis set (VBS) and wall-loss formulations to examine the predicted extent of particle and vapor wall losses. We limit the scope of our study to the dark periods in the chamber before photo-oxidation to simplify the aerosol system for this initial study. Our model simulations suggest that over one-third of the initial particle-phase organic mass (41 %) was lost during the experiments, and over half of this particle-organic mass loss was from direct particle wall loss (65 % of the loss) with the remainder from evaporation of the particles driven by vapor losses to the walls (35 % of the loss). We perform a series of sensitivity tests to understand uncertainties in our simulations. Uncertainty in the initial wood-smoke volatility distribution contributes 18 % uncertainty to the final particle-organic mass remaining in the chamber (relative to base-assumption simulation). We show that the total mass loss may depend on the effective saturation concentration of vapor with respect to the walls as these values currently vary widely in the literature. The details of smoke dilution during the filling of smog chambers may influence the mass loss to the walls, and a dilution of ~ 25:1 during the experiments increased particle-organic mass loss by 33 % compared to a simulation where we assume the particles and vapors are initially in equilibrium in the chamber. Finally, we discuss how our findings may influence interpretations of emission factors and SOA production in wood-smoke smog-chamber experiments.« less

Differential Left Hippocampal Activation during Retrieval with Different Types of Reminders: An fMRI Study of the Reconsolidation Process

PubMed Central

De Pino, Gabriela; Fernández, Rodrigo Sebastián; Villarreal, Mirta Fabiana; Pedreira, María Eugenia

2016-01-01

Consolidated memories return to a labile state after the presentation of cues (reminders) associated with acquisition, followed by a period of stabilization (reconsolidation). However not all cues are equally effective in initiating the process, unpredictable cues triggered it, predictable cues do not. We hypothesize that the different effects observed by the different reminder types on memory labilization-reconsolidation depend on a differential neural involvement during reminder presentation. To test it, we developed a declarative task and compared the efficacy of three reminder types in triggering the process in humans (Experiment 1). Finally, we compared the brain activation patterns between the different conditions using functional magnetic resonance imaging (fMRI) (Experiment 2). We confirmed that the unpredictable reminder is the most effective in initiating the labilization-reconsolidation process. Furthermore, only under this condition there was differential left hippocampal activation during its presentation. We suggest that the left hippocampus is detecting the incongruence between actual and past events and allows the memory to be updated. PMID:26991776

Bovine milk-derived α-lactalbumin inhibits colon inflammation and carcinogenesis in azoxymethane and dextran sodium sulfate-treated mice.

PubMed

Yamaguchi, Makoto; Takai, Shoko; Hosono, Akira; Seki, Taiichiro

2014-01-01

Cyclooxygenase-2 is expressed early in colon carcinogenesis and plays crucial role in the progress of the disease. Recently, we found that α-lactalbumin had anti-inflammatory activity by inhibiting cyclooxygenase-2. In experiment 1, we investigated the effects of α-lactalbumin on the colon carcinogenesis initiated with azoxymethane (AOM) followed by promotion with dextran sodium sulfate (DSS) in mice. Dietary treatment with α-lactalbumin decreased fecal occult blood score at 3 days after DSS intake. α-Lactalbumin also decreased the colon tumor at week 9. In experiment 2, AOM-treated mice were sacrificed at 7 days after DSS intake. The plasma and colon prostaglandin E2 (PGE2) levels in AOM/DSS-treated mice were higher than those in the DSS-treated mice without initiation by AOM. α-Lactalbumin decreased PGE2 in both plasma and colon. These results suggest that α-lactalbumin effectively inhibited colon carcinogenesis, and the inhibition may be due to the decreased PGE2 by inhibiting cyclooxygenase-2 at cancer promotion stages.

[Government management and society: information, technology and scientific output].

PubMed

Ribeiro, Patrícia; Sophia, Daniela Carvalho; Grigório, Deise de Araújo

2007-01-01

The complexity of government tasks today suggests that virtual interaction processes that could streamline flows and exchanges of information between governments and society in public policymaking may contribute to more effective intervention that is more closely attuned to the heterogeneity and diversity of social problems. Innovative participatory government administration initiatives have proliferated, together with the extension of public control over government actions, handled through by information technologies. Exploring this field, this paper identifies some key issues for better demarcation and qualification of such initiatives in public sector management, based on the authors' own experience in leading an institutional project designed to empower the political, technical, and communicative participation of society in discussions of the implementation of the Unified National Health System in Brazil. Based on a review of the literature analyzing the links among information, technology, development, and democracy, and particularly with regard to social management, this paper systematizes aspects for consideration drawn from in experiences of interactions between government and society, mediated by scientific knowledge, fostering greater transparency and plurality of views in government management.

Recursive processes in self-affirmation: intervening to close the minority achievement gap.

PubMed

Cohen, Geoffrey L; Garcia, Julio; Purdie-Vaughns, Valerie; Apfel, Nancy; Brzustoski, Patricia

2009-04-17

A 2-year follow-up of a randomized field experiment previously reported in Science is presented. A subtle intervention to lessen minority students' psychological threat related to being negatively stereotyped in school was tested in an experiment conducted three times with three independent cohorts (N = 133, 149, and 134). The intervention, a series of brief but structured writing assignments focusing students on a self-affirming value, reduced the racial achievement gap. Over 2 years, the grade point average (GPA) of African Americans was, on average, raised by 0.24 grade points. Low-achieving African Americans were particularly benefited. Their GPA improved, on average, 0.41 points, and their rate of remediation or grade repetition was less (5% versus 18%). Additionally, treated students' self-perceptions showed long-term benefits. Findings suggest that because initial psychological states and performance determine later outcomes by providing a baseline and initial trajectory for a recursive process, apparently small but early alterations in trajectory can have long-term effects. Implications for psychological theory and educational practice are discussed.

A scoping review to explore the suitability of interactive voice response to conduct automated performance measurement of the patient's experience in primary care.

PubMed

Falconi, Michael; Johnston, Sharon; Hogg, William

2016-05-01

Practice-based performance measurement is fundamental for improvement and accountability in primary care. Traditional performance measurement of the patient's experience is often too costly and cumbersome for most practices. This scoping review explores the literature on the use of interactive voice response (IVR) telephone surveys to identify lessons for its use for collecting data on patient-reported outcome measures at the primary care practice level. The literature suggests IVR could potentially increase the capacity to reach more representative patient samples and those traditionally most difficult to engage. There is potential for long-term cost effectiveness and significant decrease of the burden on practices involved in collecting patient survey data. Challenges such as low response rates, mode effects, high initial set-up costs and maintenance fees, are also reported and require careful attention. This review suggests IVR may be a feasible alternative to traditional patient data collection methods, which should be further explored.

Complete unconscious control: Using (in)action primes to demonstrate completely unconscious activation of inhibitory control mechanisms

PubMed Central

Hepler, Justin; Albarracin, Dolores

2018-01-01

Although robust evidence indicates that action initiation can occur unconsciously and unintentionally, the literature on action inhibition suggests that inhibition requires both conscious thought and intentionality. In prior research demonstrating automatic inhibition in response to unconsciously processed stimuli, the unconscious stimuli had previously been consciously associated with an inhibitory response within the context of the experiment, and participants had consciously formed a goal to activate inhibition processes when presented with the stimuli (because task instructions required participants to engage in inhibition when the stimuli occurred). Therefore, prior work suggests that some amount of conscious thought and intentionality are required for inhibitory control. In the present research, we recorded event-related potentials during two go/no-go experiments in which participants were subliminally primed with general action/inaction concepts that had never been consciously associated with task-specific responses. We provide the first demonstration that inhibitory control processes can be modulated completely unconsciously and unintentionally. PMID:23747649

Relevance and Reason Relations.

PubMed

Skovgaard-Olsen, Niels; Singmann, Henrik; Klauer, Karl Christoph

2017-05-01

This paper examines precursors and consequents of perceived relevance of a proposition A for a proposition C. In Experiment 1, we test Spohn's (2012) assumption that ∆P = P(C|A) - P(C|~A) is a good predictor of ratings of perceived relevance and reason relations, and we examine whether it is a better predictor than the difference measure (P(C|A) - P(C)). In Experiment 2, we examine the effects of relevance on probabilistic coherence in Cruz, Baratgin, Oaksford, and Over's (2015) uncertain "and-to-if" inferences. The results suggest that ∆P predicts perceived relevance and reason relations better than the difference measure and that participants are either less probabilistically coherent in "and-to-if" inferences than initially assumed or that they do not follow P(if A, then C) = P(C|A) ("the Equation"). Results are discussed in light of recent results suggesting that the Equation may not hold under conditions of irrelevance or negative relevance. Copyright © 2016 Cognitive Science Society, Inc.

An Analysis of the Time Course of Lexical Processing During Reading.

PubMed

Sheridan, Heather; Reichle, Erik D

2016-04-01

Reingold, Reichle, Glaholt, and Sheridan (2012) reported a gaze-contingent eye-movement experiment in which survival-curve analyses were used to examine the effects of word frequency, the availability of parafoveal preview, and initial fixation location on the time course of lexical processing. The key results of these analyses suggest that lexical processing begins very rapidly (after approximately 120 ms) and is supported by substantial parafoveal processing (more than 100 ms). Because it is not immediately obvious that these results are congruent with the theoretical assumption that words are processed and identified in a strictly serial manner, we attempted to simulate the experiment using the E-Z Reader model of eye-movement control (Reichle, 2011). These simulations were largely consistent with the empirical results, suggesting that parafoveal processing does play an important functional role by allowing lexical processing to occur rapidly enough to mediate direct control over when the eyes move during reading. Copyright © 2015 Cognitive Science Society, Inc.

Development and initial psychometric assessment of the reasons for pretending orgasm inventory.

PubMed

McCoy, Mark G; Welling, Lisa L M; Shackelford, Todd K

2015-02-03

Research suggests that women pretend orgasm with their partner as a mate retention strategy, but the cognitive reasons behind this deception are not well known. To explore women's cognitive reasons for pretending orgasm, we first assembled a list of the reasons women report for pretending orgasm. We refined this list using independent data collected on performance frequencies for each item, followed by a principal components analysis, to generate the Reasons for Pretending Orgasm Inventory (RPOI). We found three components encompassing the cognitive reasons women pretend orgasm: Improve Partner's Experience (i.e., increasing the quality of the sexual experience for the partner), Deception and Manipulation (i.e., deceiving the partner or manipulating his perceptions for other gains), and Hiding Sexual Disinterest (i.e., sparing the partner's feelings about the woman's lack of sexual excitement). Discussion highlights limitations of this research and the RPOI, but suggests that the RPOI is useful as a structured means for assessing women's reasons for pretending orgasm.

The Impact of Menthol Cigarettes on Smoking Initiation among Non-Smoking Young Females in Japan

PubMed Central

Connolly, Gregory N.; Behm, Ilan; Osaki, Yoneatsu; Wayne, Geoffrey F.

2011-01-01

Japan presents an excellent case-study of a nation with low female smoking rates and a negligible menthol market which changed after the cigarette market was opened to foreign competition. Internal tobacco industry documents demonstrate the intent of tobacco manufacturers to increase initiation among young females through development and marketing of menthol brands. Japanese menthol market share rose rapidly from less than 1% in 1980 to 20% in 2008. Menthol brand use was dominated by younger and female smokers, in contrast with non-menthol brands which were used primarily by male smokers. Nationally representative surveys confirm industry surveys of brand use and provide further evidence of the end results of the tobacco industry’s actions—increased female smoking in Japan. These findings suggest that female populations may be encouraged to initiate into smoking, particularly in developing nations or where female smoking rates remain low, if the tobacco industry can successfully tailor brands to them. The Japanese experience provides a warning to public health officials who wish to prevent smoking initiation among young females. PMID:21318010

The impact of menthol cigarettes on smoking initiation among non-smoking young females in Japan.

PubMed

Connolly, Gregory N; Behm, Ilan; Osaki, Yoneatsu; Wayne, Geoffrey F

2011-01-01

Japan presents an excellent case-study of a nation with low female smoking rates and a negligible menthol market which changed after the cigarette market was opened to foreign competition. Internal tobacco industry documents demonstrate the intent of tobacco manufacturers to increase initiation among young females through development and marketing of menthol brands. Japanese menthol market share rose rapidly from less than 1% in 1980 to 20% in 2008. Menthol brand use was dominated by younger and female smokers, in contrast with non-menthol brands which were used primarily by male smokers. Nationally representative surveys confirm industry surveys of brand use and provide further evidence of the end results of the tobacco industry's actions-increased female smoking in Japan. These findings suggest that female populations may be encouraged to initiate into smoking, particularly in developing nations or where female smoking rates remain low, if the tobacco industry can successfully tailor brands to them. The Japanese experience provides a warning to public health officials who wish to prevent smoking initiation among young females.

Experiments and simulations of Richtmyer-Meshkov Instability with measured,volumetric initial conditions

NASA Astrophysics Data System (ADS)

Sewell, Everest; Ferguson, Kevin; Jacobs, Jeffrey; Greenough, Jeff; Krivets, Vitaliy

2016-11-01

We describe experiments of single-shock Richtmyer-Meskhov Instability (RMI) performed on the shock tube apparatus at the University of Arizona in which the initial conditions are volumetrically imaged prior to shock wave arrival. Initial perturbations play a major role in the evolution of RMI, and previous experimental efforts only capture a single plane of the initial condition. The method presented uses a rastered laser sheet to capture additional images throughout the depth of the initial condition immediately before the shock arrival time. These images are then used to reconstruct a volumetric approximation of the experimental perturbation. Analysis of the initial perturbations is performed, and then used as initial conditions in simulations using the hydrodynamics code ARES, developed at Lawrence Livermore National Laboratory (LLNL). Experiments are presented and comparisons are made with simulation results.

Cooperative behavior cascades in human social networks.

PubMed

Fowler, James H; Christakis, Nicholas A

2010-03-23

Theoretical models suggest that social networks influence the evolution of cooperation, but to date there have been few experimental studies. Observational data suggest that a wide variety of behaviors may spread in human social networks, but subjects in such studies can choose to befriend people with similar behaviors, posing difficulty for causal inference. Here, we exploit a seminal set of laboratory experiments that originally showed that voluntary costly punishment can help sustain cooperation. In these experiments, subjects were randomly assigned to a sequence of different groups to play a series of single-shot public goods games with strangers; this feature allowed us to draw networks of interactions to explore how cooperative and uncooperative behaviors spread from person to person to person. We show that, in both an ordinary public goods game and in a public goods game with punishment, focal individuals are influenced by fellow group members' contribution behavior in future interactions with other individuals who were not a party to the initial interaction. Furthermore, this influence persists for multiple periods and spreads up to three degrees of separation (from person to person to person to person). The results suggest that each additional contribution a subject makes to the public good in the first period is tripled over the course of the experiment by other subjects who are directly or indirectly influenced to contribute more as a consequence. These results show experimentally that cooperative behavior cascades in human social networks.

Inter-subject variability modulates phonological advance planning in the production of adjective-noun phrases.

PubMed

Michel Lange, Violaine; Laganaro, Marina

2014-01-01

The literature on advance phonological planning in adjective-noun phrases (NPs) presents diverging results: while many experimental studies suggest that the entire NP is encoded before articulation, other results favor a span of encoding limited to the first word. Although cross-linguistic differences in the structure of adjective-NPs may account for some of these contrasting results, divergences have been reported even among similar languages and syntactic structures. Here we examined whether inter-individual differences account for variability in the span of phonological planning in the production of French NPs, where previous results indicated encoding limited to the first word. The span of phonological encoding is tested with the picture-word interference (PWI) paradigm using phonological distractors related to the noun or to the adjective of the NPs. In Experiment 1, phonological priming effects were limited to the first word in adjective NPs whichever the position of the adjective (pre-nominal or post-nominal). Crucially, phonological priming effects on the second word interacted with speakers' production speed suggesting different encoding strategies for participants. In Experiment 2, we tested this hypothesis further with a larger group of participants. Results clearly showed that slow and fast initializing participants presented different phonological priming patterns on the last element of adjective-NPs: while the first word was primed by a distractor for all speakers, only the slow speaker group presented a priming effect on the second element of the NP. These results show that the span of phonological encoding is modulated by inter-individual strategies: in experimental paradigms some speakers plan word by word whereas others encode beyond the initial word. We suggest that the diverging results reported in the literature on advance phonological planning may partly be reconciled in light of the present results.

Metrical expectations from preceding prosody influence perception of lexical stress.

PubMed

Brown, Meredith; Salverda, Anne Pier; Dilley, Laura C; Tanenhaus, Michael K

2015-04-01

Two visual-world experiments tested the hypothesis that expectations based on preceding prosody influence the perception of suprasegmental cues to lexical stress. The results demonstrate that listeners' consideration of competing alternatives with different stress patterns (e.g., 'jury/gi'raffe) can be influenced by the fundamental frequency and syllable timing patterns across material preceding a target word. When preceding stressed syllables distal to the target word shared pitch and timing characteristics with the first syllable of the target word, pictures of alternatives with primary lexical stress on the first syllable (e.g., jury) initially attracted more looks than alternatives with unstressed initial syllables (e.g., giraffe). This effect was modulated when preceding unstressed syllables had pitch and timing characteristics similar to the initial syllable of the target word, with more looks to alternatives with unstressed initial syllables (e.g., giraffe) than to those with stressed initial syllables (e.g., jury). These findings suggest that expectations about the acoustic realization of upcoming speech include information about metrical organization and lexical stress and that these expectations constrain the initial interpretation of suprasegmental stress cues. These distal prosody effects implicate online probabilistic inferences about the sources of acoustic-phonetic variation during spoken-word recognition. (c) 2015 APA, all rights reserved.

Rainfall Results of the Florida Area Cumulus Experiment, 1970-76.

NASA Astrophysics Data System (ADS)

Woodley, William L.; Jordan, Jill; Barnston, Anthony; Simpson, Joanne; Biondini, Ron; Flueck, John

1982-02-01

The Florida Area Cumulus Experiment of 1970-76 (FACE-1) is a single-area, randomized, exploratory experiment to determine whether seeding cumuli for dynamic effects (dynamic seeding) can be used to augment convective rainfall over a substantial target area (1.3 × 104 km2) in south Florida. Rainfall is estimated using S-band radar observations after adjustment by raingages. The two primary response variables are rain volumes in the total target (TT) and in the floating target (FT), the most intensely treated portion of the target. The experimental unit is the day and the main observational period is the 6 h after initiation of treatment (silver iodide flares on seed days and either no flares or placebos on control days). Analyses without predictors suggest apparent increases in both the location (means and medians) and the dispersion (standard deviation and interquartile range) characteristics of rainfall due to seeding in the FT and TT variables with substantial statistical support for the FT results and lesser statistical support for the TT results. Analyses of covariance using meteorologically meaningful predictor variables suggest a somewhat larger effect of seeding with stronger statistical support. These results are interpreted in terms of the FACE conceptual model.

High-resolution experiments on chemical oxidation of DNAPL in variable-aperture fractures

NASA Astrophysics Data System (ADS)

Arshadi, Masoud; Rajaram, Harihar; Detwiler, Russell L.; Jones, Trevor

2015-04-01

Chemical oxidation of dense nonaqueous-phase liquids (DNAPLs) by permanganate has emerged as an effective remediation strategy in fractured rock. We present high-resolution experimental investigations in transparent analog variable-aperture fractures to improve understanding of chemical oxidation of residual entrapped trichloroethylene (TCE) in fractures. Four experiments were performed with different permanganate concentrations, flow rates, and initial TCE phase geometry. The initial aperture field and evolving entrapped-phase geometry were quantified for each experiment. The integrated mass transfer rate from the TCE phase for all experiments exhibited three time regimes: an early-time regime with slower mass transfer rates limited by low specific interfacial area; an intermediate-time regime with higher mass transfer rates resulting from breakup of large TCE blobs, which greatly increases specific interfacial area; and a late-time regime with low mass transfer rates due to the deposition of MnO2 precipitates. In two experiments, mass balance analyses suggested that TCE mass removal rates exceeded the maximum upper bound mass removal rates derived by assuming that oxidation and dissolution are the only mechanisms for TCE mass removal. We propose incomplete oxidation by permanganate and TCE solubility enhancement by intermediate reaction products as potential mechanisms to explain this behavior. We also speculate that some intermediate reaction products with surfactant-like properties may play a role in lowering the TCE-water interfacial tension, thus causing breakup of large TCE blobs. Our quantitative experimental measurements will be useful in the context of developing accurate computational models for chemical oxidation of TCE in fractures.

Bidirectional Relationships Between Fatigue and Everyday Experiences in Persons Living With HIV.

PubMed

Cook, Paul F; Hartson, Kimberly R; Schmiege, Sarah J; Jankowski, Catherine; Starr, Whitney; Meek, Paula

2016-06-01

Fatigue symptoms are very common among persons living with HIV (PLWH). Fatigue is related to functional and psychological problems and to treatment nonadherence. Using secondary data from ecological momentary assessment, we examined fatigue as a predictor of PLWH everyday experiences. In bidirectional analyses based on the shape shifters model, we also examined these experiences as predictors of fatigue. Data were examined from 67 PLWH who completed daily surveys on a handheld computer. Brief validated scales were used to assess participants' control beliefs, mood, stress, coping, social support, experience of stigma, and motivation. At the beginning and end of the study, fatigue was measured with two CES-D items that have been used in past HIV symptom research. Multilevel models and logistic regression were used to test reciprocal predictive relationships between variables. Moderate to severe fatigue affected 45% of PLWH in the study. Initial fatigue predicted PLWH subsequent overall level of control beliefs, mood, stress, coping, and social support, all p < .05. These state variables remained relatively constant over time, regardless of participants' initial fatigue. In tests for reciprocal relationships with 33 PLWH, average daily stress, OR = 4.74, and stigma, OR = 4.86, also predicted later fatigue. Fatigue predicted several daily survey variables including stress and social support. Stress and support in turn predicted fatigue at a later time, suggesting a self-perpetuating cycle but also a possible avenue for intervention. Future studies should examine daily variation in fatigue among PLWH and its relation to other everyday experiences and behaviors. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

The experience of dentists who gained enhanced skills in endodontics within a novel pilot training programme.

PubMed

Eliyas, S; Briggs, P; Gallagher, J E

2017-02-24

Objective To explore the experiences of primary care dentists following training to enhance endodontic skills and their views on the implications for the NHS.Design Qualitative study using anonymised free text questionnaires.Setting Primary care general dental services within the National Health Service (NHS) in London, United Kingdom.Subjects and methods Eight primary care dentists who completed this training were asked about factors affecting participant experience of the course, perceived impact on themselves, their organisation, their patients and barriers/facilitators to providing endodontic treatment in NHS primary care. Data were transferred verbatim to a spreadsheet and thematically analysed.Intervention 24-month part-time educational and service initiative to provide endodontics within the NHS, using a combination of training in simulation lab and treatment of patients in primary care.Results Positive impacts were identified at individual (gains in knowledge, skills, confidence, personal development), patient (more teeth saved, quality of care improved) and system levels (access, value for money). Suggested developments for future courses included more case discussions, teaching of practical skills earlier in the course and refinement of the triaging processes. Barriers to using the acquired skills in providing endodontic treatment in primary care within the NHS were perceived to be resources (remuneration, time, skills) and accountability. Facilitators included appropriately remunerated contracts, necessary equipment and time.Conclusion This novel pilot training programme in endodontics combining general practice experience with education/training, hands-on experience and a portfolio was perceived by participants as beneficial for extending skills and service innovation in primary dental care. The findings provide insight into primary dental care practitioners' experience with education/training and have implications for future educational initiatives in support of systems innovation within the NHS.

Parents' experiences with neonatal home care following initial care in the neonatal intensive care unit: a phenomenological hermeneutical interview study.

PubMed

Dellenmark-Blom, Michaela; Wigert, Helena

2014-03-01

A descriptive study of parents' experiences with neonatal home care following initial care in the neonatal intensive care unit. As survival rates improve among premature and critically ill infants with an increased risk of morbidity, parents' responsibilities for neonatal care grow in scope and degree under the banner of family-centred care. Concurrent with medical advances, new questions arise about the role of parents and the experience of being provided neonatal care at home. An interview study with a phenomenological hermeneutic approach. Parents from a Swedish neonatal (n = 22) home care setting were extensively interviewed within one year of discharge. Data were collected during 2011-2012. The main theme of the findings is that parents experience neonatal home care as an inner emotional journey, from having a child to being a parent. This finding derives from three themes: the parents' experience of leaving the hospital milieu in favour of establishing independent parenthood, maturing as a parent and processing experiences during the period of neonatal intensive care. This study suggests that neonatal home care is experienced as a care structure adjusted to incorporate parents' needs following discharge from a neonatal intensive care unit. Neonatal home care appears to bridge the gap between hospital and home, supporting the family's adaptation to life in the home setting. Parents become empowered to be primary caregivers, having nurse consultants serving the needs of the whole family. Neonatal home care may therefore be understood as the implementation of family-centred care during the transition from NICU to home. © 2013 John Wiley & Sons Ltd.

From diagnosis through survivorship: health-care experiences of colorectal cancer survivors with ostomies

PubMed Central

Grant, Marcia; McMullen, Carmit K.; Altschuler, Andrea; Mohler, M. Jane; Hornbrook, Mark C.; Herrinton, Lisa J.; Krouse, Robert S.

2014-01-01

Purpose The journey from diagnosis through treatment to survivorship can be challenging for colorectal cancer (CRC) survivors with permanent ostomies. Memories of both the positive and negative health-care interactions can persist years after the initial diagnosis and treatment. The purpose of this paper is to describe the health-care experiences of long-term (>5 years) CRC survivors with ostomies. Methods Thirty-three CRC survivors with ostomies who were members of Kaiser Permanente, an integrated care organization, in Oregon, southwestern Washington and northern California participated in eight focus groups. Discussions from the focus groups were recorded, transcribed, and analyzed for potential categories and themes. Results Health-care-related themes described CRC survivors’ experiences with diagnosis, treatment decision-making, initial experiences with ostomy, and survivorship. Participants discussed both positive and negative health-care-related experiences, including the need for continued access to trained nurses for ostomy self-care, access to peer support, and resources related to managing persistent, debilitating symptoms. Conclusions Long-term CRC survivors with ostomies have both positive and negative health-care experiences, regardless of health-related quality of life (HRQOL) and gender. Long-term support mechanisms and quality survivorship care that CRC survivors with ostomies can access are needed to promote positive adjustments and improved HRQOL. Structured abstract The current literature in CRC survivor-ship suggests that HRQOL concerns can persist years after treatment completion. The coordination of care to manage persistent late- and long-term effects are still lacking for CRC survivors living with an ostomy. Findings from this qualitative analysis will aid in the development of support strategies that foster more positive adjustments for CRC survivors living with an ostomy and support their ongoing ostomy-related needs. PMID:24442998

From diagnosis through survivorship: health-care experiences of colorectal cancer survivors with ostomies.

PubMed

Sun, Virginia; Grant, Marcia; McMullen, Carmit K; Altschuler, Andrea; Mohler, M Jane; Hornbrook, Mark C; Herrinton, Lisa J; Krouse, Robert S

2014-06-01

The journey from diagnosis through treatment to survivorship can be challenging for colorectal cancer (CRC) survivors with permanent ostomies. Memories of both the positive and negative health-care interactions can persist years after the initial diagnosis and treatment. The purpose of this paper is to describe the health-care experiences of long-term (>5 years) CRC survivors with ostomies. Thirty-three CRC survivors with ostomies who were members of Kaiser Permanente, an integrated care organization, in Oregon, southwestern Washington and northern California participated in eight focus groups. Discussions from the focus groups were recorded, transcribed, and analyzed for potential categories and themes. Health-care-related themes described CRC survivors' experiences with diagnosis, treatment decision-making, initial experiences with ostomy, and survivorship. Participants discussed both positive and negative health-care-related experiences, including the need for continued access to trained nurses for ostomy self-care, access to peer support, and resources related to managing persistent, debilitating symptoms. Long-term CRC survivors with ostomies have both positive and negative health-care experiences, regardless of health-related quality of life (HRQOL) and gender. Long-term support mechanisms and quality survivorship care that CRC survivors with ostomies can access are needed to promote positive adjustments and improved HRQOL. The current literature in CRC survivorship suggests that HRQOL concerns can persist years after treatment completion. The coordination of care to manage persistent late- and long-term effects are still lacking for CRC survivors living with an ostomy. Findings from this qualitative analysis will aid in the development of support strategies that foster more positive adjustments for CRC survivors living with an ostomy and support their ongoing ostomy-related needs.

Influence of spatial and temporal manipulations on the anxiolytic efficacy of chlordiazepoxide in mice previously exposed to the elevated plus-maze.

PubMed

Holmes, A; Rodgers, R J

1999-11-01

It has been widely reported that the anxiolytic efficacy of benzodiazepines in the elevated plus-maze test is abolished in subjects (rats or mice) that have been given a single prior undrugged experience of the test apparatus. The present series of experiments was designed to further characterise the key experiential determinants of this intriguing phenomenon in Swiss Webster mice. Using a standard 5 min test duration for both trials, Experiment 1 confirmed the anxiolytic efficacy of chlordiazepoxide (CDP; 5-20 mg/kg) in mice naive to the plus-maze, but a virtual elimination of drug effects in animals that had been pre-exposed to the maze 24 h earlier. Experiments 2 and 3 demonstrated that, while extending the duration of initial exposure to 10 min did not prevent the loss of CDP (10 mg/kg) efficacy in a standard-duration second trial, increasing the duration of both trials reinstated an anxiolytic profile for the compound. Finally, although trial 1 confinement to an open arm did not compromise CDP efficacy when animals were subsequently allowed to freely explore the maze (Experiment 4), closed arm confinement during initial exposure abolished the drug's anxiolytic action upon retest (Experiment 5). In contrast to previous findings in rats, these data suggest that the experientially induced loss of benzodiazepine efficacy in the mouse plus-maze depends rather critically upon prior discovery and exploration of relatively safe areas of the maze (i.e. closed arms). Results are discussed in relation to the hypothesis that the absence of an anxiolytic response to benzodiazepines in plus-maze-experienced subjects reflects the acquisition of an open arm phobia during trial 1.

A self-agency bias in preschoolers' causal inferences

PubMed Central

Kushnir, Tamar; Wellman, Henry M.; Gelman, Susan A.

2013-01-01

Preschoolers' causal learning from intentional actions – causal interventions – is subject to a self-agency bias. We propose that this bias is evidence-based; it is responsive to causal uncertainty. In the current studies, two causes (one child-controlled, one experimenter-controlled) were associated with one or two effects, first independently, then simultaneously. When initial independent effects were probabilistic, and thus subsequent simultaneous actions were causally ambiguous, children showed a self-agency bias. Children showed no bias when initial effects were deterministic. Further controls establish that children's self-agency bias is not a wholesale preference but rather is influenced by uncertainty in causal evidence. These results demonstrate that children's own experience of action influences their causal learning, and suggest possible benefits in uncertain and ambiguous everyday learning contexts. PMID:19271843

Using the Internet to access information inflates future use of the Internet to access other information.

PubMed

Storm, Benjamin C; Stone, Sean M; Benjamin, Aaron S

2017-07-01

The ways in which people learn, remember, and solve problems have all been impacted by the Internet. The present research explored how people become primed to use the Internet as a form of cognitive offloading. In three experiments, we show that using the Internet to retrieve information alters a person's propensity to use the Internet to retrieve other information. Specifically, participants who used Google to answer an initial set of difficult trivia questions were more likely to decide to use Google when answering a new set of relatively easy trivia questions than were participants who answered the initial questions from memory. These results suggest that relying on the Internet to access information makes one more likely to rely on the Internet to access other information.

Mechanically triggered heterolytic unzipping of a low-ceiling-temperature polymer

NASA Astrophysics Data System (ADS)

Diesendruck, Charles E.; Peterson, Gregory I.; Kulik, Heather J.; Kaitz, Joshua A.; Mar, Brendan D.; May, Preston A.; White, Scott R.; Martínez, Todd J.; Boydston, Andrew J.; Moore, Jeffrey S.

2014-07-01

Biological systems rely on recyclable materials resources such as amino acids, carbohydrates and nucleic acids. When biomaterials are damaged as a result of aging or stress, tissues undergo repair by a depolymerization-repolymerization sequence of remodelling. Integration of this concept into synthetic materials systems may lead to devices with extended lifetimes. Here, we show that a metastable polymer, end-capped poly(o-phthalaldehyde), undergoes mechanically initiated depolymerization to revert the material to monomers. Trapping experiments and steered molecular dynamics simulations are consistent with a heterolytic scission mechanism. The obtained monomer was repolymerized by a chemical initiator, effectively completing a depolymerization-repolymerization cycle. By emulating remodelling of biomaterials, this model system suggests the possibility of smart materials where aging or mechanical damage triggers depolymerization, and orthogonal conditions regenerate the polymer when and where necessary.

Optical interference with noncoherent states

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

Sagi, Yoav; Firstenberg, Ofer; Fisher, Amnon

2003-03-01

We examine a typical two-source optical interference apparatus consisting of two cavities, a beam splitter, and two detectors. We show that field-field interference occurs even when the cavities are not initially in coherent states but rather in other nonclassical states. However, we find that the visibility of the second-order interference, that is, the expectation values of the detectors' readings, changes from 100%, when the cavities are prepared in coherent states, to zero visibility when they are initially in single Fock states. We calculate the fourth-order interference, and for the latter case find that it corresponds to a case where themore » currents oscillate with 100% visibility, but with a random phase for every experiment. Finally, we suggest an experimental realization of the apparatus with nonclassical sources.« less

Visual Semiotics & Uncertainty Visualization: An Empirical Study.

PubMed

MacEachren, A M; Roth, R E; O'Brien, J; Li, B; Swingley, D; Gahegan, M

2012-12-01

This paper presents two linked empirical studies focused on uncertainty visualization. The experiments are framed from two conceptual perspectives. First, a typology of uncertainty is used to delineate kinds of uncertainty matched with space, time, and attribute components of data. Second, concepts from visual semiotics are applied to characterize the kind of visual signification that is appropriate for representing those different categories of uncertainty. This framework guided the two experiments reported here. The first addresses representation intuitiveness, considering both visual variables and iconicity of representation. The second addresses relative performance of the most intuitive abstract and iconic representations of uncertainty on a map reading task. Combined results suggest initial guidelines for representing uncertainty and discussion focuses on practical applicability of results.

A causal model explaining the relationships governing beliefs, attitudes, and hypnotic responsiveness.

PubMed

Shimizu, Takahiro

2014-01-01

The author developed a new scale aimed at measuring beliefs about "hypnotic states" and investigated the influence of such beliefs and attitudes on hypnotic responses in a large sample of Japanese undergraduate students. Exploratory factor analysis of this new questionnaire examining beliefs about hypnotic states yielded four factors: Dissociative or Depersonalized Experience, Loss of Self-Control, Therapeutic Expectation, and Arousing Extraordinary Ability. The results of structural equation modeling showed that Therapeutic Expectation and Arousing Extraordinary Ability influenced hypnotizability through attitudes toward hypnosis, while also directly affecting subjective experiences without mediating attitudes. Present findings suggest that it is more effective to enhance therapeutic expectations than to correct misconceptions about hypnotic states in modification of patients' beliefs before initiating treatment.

First year undergraduate nursing students and nursing mentors: An evaluation of their experience of specialist areas as their hub practice learning environment.

PubMed

McCallum, Jacqueline; Lamont, David; Kerr, Emma-Louise

2016-01-01

Specialist environments have traditionally not been considered as practice learning environments for year one nursing students. Through implementation of the hub and spoke model of practice learning this was implemented across one health board and Higher Education Institution in Scotland. Sixty nine students from specialist and 147 from general areas out of a total population of 467 students (46.2%) and thirteen mentors from specialist and 26 from general areas out of a total 577 mentors (6.7%) completed a questionnaire. The findings support this initiative and suggest in some cases student experiences are more positive in specialist environments. Copyright © 2015 Elsevier Ltd. All rights reserved.

Video measurement of the muzzle velocity of a potato gun

NASA Astrophysics Data System (ADS)

Jasperson, Christopher; Pollman, Anthony

2011-09-01

Using first principles, a theoretical equation for the maximum and actual muzzle velocities for a pneumatic cannon was recently derived. For a fixed barrel length, this equation suggests that the muzzle velocity can be enhanced by maximizing the product of the initial pressure and the volume of the propellant gas and decreasing the projectile mass. The present paper describes the results of experiments conducted to verify the validity of this theoretical equation. A high-speed video camera was used to quantify muzzle velocity for potatoes of varying mass exiting a pneumatic cannon for gauge pressures ranging from 310 to 830 kPa. The experiments verified that a friction modified version of the theoretical equation is qualitatively and quantitatively accurate for potato masses above 100 g.

An Initial Investigation of Sexual Minority Youth Involvement in School-Based Extracurricular Activities.

PubMed

Toomey, Russell B; Russell, Stephen T

2013-06-01

Sexual minority youth are at risk for negative school-based experiences and poor academic outcomes. Yet, little is known about their experiences in positive school-based contexts. Using the National Longitudinal Study of Adolescent Health (1,214 sexual minority and 11,427 heterosexual participants), this study compared participation rates in, predictors of, and outcomes associated with three types of school-based extracurricular activities - sports, arts, and school clubs - by sexual orientation and gender. Findings revealed several significant sexual orientation and gender differences in participation rates in school-based sports, clubs, and arts activities. Further, findings suggested that the outcomes associated with extracurricular activity involvement do not differ by sexual orientation and gender; however, predictors of participation in these domains varied across groups.

Incorporating TPC observed parameters and QuikSCAT surface wind observations into hurricane initialization using 4D-VAR approaches

NASA Astrophysics Data System (ADS)

Park, Kyungjeen

This study aims to develop an objective hurricane initialization scheme which incorporates not only forecast model constraints but also observed features such as the initial intensity and size. It is based on the four-dimensional variational (4D-Var) bogus data assimilation (BDA) scheme originally proposed by Zou and Xiao (1999). The 4D-Var BDA consists of two steps: (i) specifying a bogus sea level pressure (SLP) field based on parameters observed by the Tropical Prediction Center (TPC) and (ii) assimilating the bogus SLP field under a forecast model constraint to adjust all model variables. This research focuses on improving the specification of the bogus SLP indicated in the first step. Numerical experiments are carried out for Hurricane Bonnie (1998) and Hurricane Gordon (2000) to test the sensitivity of hurricane track and intensity forecasts to specification of initial vortex. Major results are listed below: (1) A linear regression model is developed for determining the size of initial vortex based on the TPC observed radius of 34kt. (2) A method is proposed to derive a radial profile of SLP from QuikSCAT surface winds. This profile is shown to be more realistic than ideal profiles derived from Fujita's and Holland's formulae. (3) It is found that it takes about 1 h for hurricane prediction model to develop a conceptually correct hurricane structure, featuring a dominant role of hydrostatic balance at the initial time and a dynamic adjustment in less than 30 minutes. (4) Numerical experiments suggest that track prediction is less sensitive to the specification of initial vortex structure than intensity forecast. (5) Hurricane initialization using QuikSCAT-derived initial vortex produced a reasonably good forecast for hurricane landfall, with a position error of 25 km and a 4-h delay at landfalling. (6) Numerical experiments using the linear regression model for the size specification considerably outperforms all the other formulations tested in terms of the intensity prediction for both Hurricanes. For examples, the maximum track error is less than 110 km during the entire three-day forecasts for both hurricanes. The simulated Hurricane Gordon using the linear regression model made a nearly perfect landfall, with no position error and only 1-h error in landfalling time. (7) Diagnosis of model output indicates that the initial vortex specified by the linear regression model produces larger surface fluxes of sensible heat, latent heat and moisture, as well as stronger downward angular momentum transport than all the other schemes do. These enhanced energy supplies offset the energy lost caused by friction and gravity wave propagation, allowing for the model to maintain a strong and realistic hurricane during the entire forward model integration.

40 CFR 725.235 - Conditions of exemption for activities conducted inside a structure.

Code of Federal Regulations, 2011 CFR

2011-07-01

... experiments subject to Institutional Biosafety Committee review, or notification simultaneous with initiation of the experiment, the information submitted for review or notification, along with standard... experiments exempt from Institutional Biosafety Committee review or notification simultaneous with initiation...

40 CFR 725.235 - Conditions of exemption for activities conducted inside a structure.

Code of Federal Regulations, 2014 CFR

2014-07-01

... experiments subject to Institutional Biosafety Committee review, or notification simultaneous with initiation of the experiment, the information submitted for review or notification, along with standard... experiments exempt from Institutional Biosafety Committee review or notification simultaneous with initiation...

40 CFR 725.235 - Conditions of exemption for activities conducted inside a structure.

Code of Federal Regulations, 2013 CFR

2013-07-01

... experiments subject to Institutional Biosafety Committee review, or notification simultaneous with initiation of the experiment, the information submitted for review or notification, along with standard... experiments exempt from Institutional Biosafety Committee review or notification simultaneous with initiation...

40 CFR 725.235 - Conditions of exemption for activities conducted inside a structure.

Code of Federal Regulations, 2012 CFR

2012-07-01

... experiments subject to Institutional Biosafety Committee review, or notification simultaneous with initiation of the experiment, the information submitted for review or notification, along with standard... experiments exempt from Institutional Biosafety Committee review or notification simultaneous with initiation...

Incremental change or initial differences? Testing two models of marital deterioration.

PubMed

Lavner, Justin A; Bradbury, Thomas N; Karney, Benjamin R

2012-08-01

Most couples begin marriage intent on maintaining a fulfilling relationship, but some newlyweds soon struggle, and others continue to experience high levels of satisfaction. Do these diverse outcomes result from an incremental process that unfolds over time, as prevailing models suggest, or are they a manifestation of initial differences that are largely evident at the start of the marriage? Using 8 waves of data collected over the first 4 years of marriage (N = 502 spouses, or 251 newlywed marriages), we tested these competing perspectives first by identifying 3 qualitatively distinct relationship satisfaction trajectory groups and then by determining the extent to which spouses in these groups were differentiated on the basis of (a) initial scores and (b) 4-year changes in a set of established predictor variables, including relationship problems, aggression, attributions, stress, and self-esteem. The majority of spouses exhibited high, stable satisfaction over the first 4 years of marriage, whereas declining satisfaction was isolated among couples with relatively low initial satisfaction. Across all predictor variables, initial values afforded stronger discrimination of outcome groups than did rates of change in these variables. Thus, readily measured initial differences are potent antecedents of relationship deterioration, and studies are now needed to clarify the specific ways in which initial indices of risk come to influence changes in spouses' judgments of relationship satisfaction. PsycINFO Database Record (c) 2012 APA, all rights reserved.

Incremental Change or Initial Differences? Testing Two Models of Marital Deterioration

PubMed Central

Lavner, Justin A.; Bradbury, Thomas N.; Karney, Benjamin R.

2012-01-01

Most couples begin marriage intent on maintaining a fulfilling relationship, but some newlyweds soon struggle while others continue to experience high levels of satisfaction. Do these diverse outcomes result from an incremental process that unfolds over time, as prevailing models suggest, or are they a manifestation of initial differences that are largely evident at the start of the marriage? Using eight waves of data collected over the first 4 years of marriage (N = 502 spouses, or 251 newlywed marriages), we tested these competing perspectives first by identifying three qualitatively distinct relationship satisfaction trajectory groups and then by determining the extent to which spouses in these groups were differentiated on the basis of (a) initial scores and (b) 4-year changes in a set of established predictor variables, including relationship problems, aggression, attributions, stress, and self-esteem. The majority of spouses exhibited high, stable satisfaction over the first four years of marriage, whereas declining satisfaction was isolating among couples with relatively low initial satisfaction. Across all predictor variables, initial values afforded stronger discrimination of outcome groups than did rates of change in these variables. Thus, readily-measured initial differences are potent antecedents of relationship deterioration, and studies are now needed to clarify the specific ways in which initial indices of risk come to influence changes in spouses’ judgments of relationship satisfaction. PMID:22709260

Auditory evoked potential measurements in elasmobranchs

NASA Astrophysics Data System (ADS)

Casper, Brandon; Mann, David

2005-04-01

Auditory evoked potentials (AEP) were first used to examine hearing in elasmobranchs by Corwin and Bullock in the late 1970s and early 1980s, marking the first time AEPs had been measured in fishes. Results of these experiments identified the regions of the ear and brain in which sound is processed, though no actual hearing thresholds were measured. Those initial experiments provided the ground work for future AEP experiments to measure fish hearing abilities in a manner that is much faster and more convenient than classical conditioning. Data will be presented on recent experiments in which AEPs were used to measure the hearing thresholds of two species of elasmobranchs: the nurse shark, Ginglymostoma cirratum, and the yellow stingray, Urobatis jamaicencis. Audiograms were analyzed and compared to previously published audiograms obtained using classical conditioning with results indicating that hearing thresholds were similar for the two methods. These data suggest that AEP testing is a viable option when measuring hearing in elasmobranchs and can increase the speed in which future hearing measurements can be obtained.

Dynamic fracture behavior of single and contacting Poly(methyl methacrylate) particles

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

Parab, Niranjan D.; Guo, Zherui; Hudspeth, Matthew C.

Fracture behaviors of single, two, and multiple contacting spherical Poly (methyl methacrylate) (PMMA) particles were recorded using high speed synchrotron X-ray phase contrast imaging. A miniaturized Kolsky bar setup was used to apply dynamic compressive loading on the PMMA particles. In both single and two particle experiments, cracking initiated near the center of the particles and propagated towards the contacts. The crack bifurcated near the contact points for single particle experiments, thus forming conical fragments. The crack bifurcation and subsequent conical fragment formation was observed only at the particle-particle contact for two particle experiments. The particles were observed to fracturemore » in hemispherical fragments normal to the contact plane in the multiparticle experiments. The observed failure mechanisms strongly suggest that the maximum tensile stress near the center of the particle is the critical parameter governing fracture of the particles. Moreover, the compressive stress under the contact areas led to the bifurcation and subsequent conical fragment formation.« less

Dynamic fracture behavior of single and contacting Poly(methyl methacrylate) particles

DOE PAGES

Parab, Niranjan D.; Guo, Zherui; Hudspeth, Matthew C.; ...

2017-09-19

Fracture behaviors of single, two, and multiple contacting spherical Poly (methyl methacrylate) (PMMA) particles were recorded using high speed synchrotron X-ray phase contrast imaging. A miniaturized Kolsky bar setup was used to apply dynamic compressive loading on the PMMA particles. In both single and two particle experiments, cracking initiated near the center of the particles and propagated towards the contacts. The crack bifurcated near the contact points for single particle experiments, thus forming conical fragments. The crack bifurcation and subsequent conical fragment formation was observed only at the particle-particle contact for two particle experiments. The particles were observed to fracturemore » in hemispherical fragments normal to the contact plane in the multiparticle experiments. The observed failure mechanisms strongly suggest that the maximum tensile stress near the center of the particle is the critical parameter governing fracture of the particles. Moreover, the compressive stress under the contact areas led to the bifurcation and subsequent conical fragment formation.« less

Retrieval attempts enhance learning regardless of time spent trying to retrieve.

PubMed

Vaughn, Kalif E; Hausman, Hannah; Kornell, Nate

2017-03-01

Attempting to retrieve information from memory is an engaging cognitive activity. We predicted that people would learn more when they had spent more time attempting to retrieve. In experiments 1a and 1b, participants were shown trivia questions for 0, 5, 10, or 30 seconds and then the answer was revealed. They took a final test immediately or after 48 hours. Retrieval enhanced learning, but the length of the retrieval attempt had no effect (i.e., final test performance was equivalent in the 5-, 10-, and 30-second conditions and worse in the 0-second condition). During the initial retrieval attempt, more time did increase recall, suggesting that participants continued to engage in productive retrieval activities when given more time. Showing the answer for longer (7 versus 2 seconds) increased learning in Experiments 2a and 2b. Experiment 3 examined the effect of retrieval success and Experiment 4 replicated the results using different materials. These results have direct implications for current theories of retrieval.

Where are the women? Campus climate and the degree aspirations of women in science, technology, engineering and mathematics programs

NASA Astrophysics Data System (ADS)

Schulz, Phyllis

Women remain underrepresented in science, technology, engineering, and mathematics (STEM) at all levels of higher education, which has become a concern in the competitive global marketplace. Using both quantitative and qualitative analysis, this dissertation sought to learn more about how the campus climate and self-concept influence the degree aspirations of female undergraduate students majoring in STEM programs. Using the Beginning Post-Secondary dataset, regression analyses showed that a student's initial degree aspirations, SAT scores, and interactions with faculty were all positively related to their degree aspirations three years later. Interviews with seven current STEM undergraduates confirmed the importance of interaction with faculty and suggested undergraduate research and classroom experiences also play a role in the degree aspirations of STEM students. Three of the seven students interviewed began their undergraduate educations as non-STEM majors, suggesting that the traditional STEM pipeline may no longer be the norm. These findings suggest that both future research and current practitioners should focus on undergraduate STEM classroom and research experiences. Additionally, the characteristics of students who switch into STEM majors should be explored so that we may continue to expand the number of students pursuing STEM degrees.

Creating beauty: creativity compensates for low physical attractiveness when individuals assess the attractiveness of social and romantic partners

PubMed Central

2017-01-01

Although creativity is attractive in a potential mate, it is unclear (i) whether the effects of creativity on attractiveness generalize to other social contexts and (ii) whether creativity has equivalent effects on men's and women's attractiveness. As social knowledge of creativity may either enhance or ‘offset’ the appeal of social partners who differ in physical attractiveness, three repeated measures experiments were conducted to directly address these issues. Here, participants rated a series of face–text pairs for attractiveness on trials that differed in one of four combinations of facial attractiveness (attractive and less attractive) and creativity (creative and less creative), rating story-tellers in two experiments (short interpretations of an identical painting) and creative ideas in a further experiment (alternative uses for an everyday object). Regardless of the sex of the judge, creativity and facial attractiveness had independent effects on men's overall attractiveness (initial experiment) and, in further experiments, more substantial effects on the attractiveness of men with less attractive faces than men with attractive faces (when using a different measure of creativity) and specific effects on the attractiveness of individuals with less attractive faces (when using different face stimuli). Collectively, across three experiments, these findings suggest that creativity may compensate for putative cues to lower biological ‘quality’ and that the benefits of creativity to social groups more generally enhance attraction to creative men (in two experiments) and creative men and women (one experiment). More broadly, the data suggest that species can integrate knowledge of cognitive intelligence with visual cues to biological ‘quality’ to facilitate mate and/or ally choice. PMID:28484614

Critical interpretive synthesis of barriers and facilitators to TB treatment in immigrant populations.

PubMed

Lin, S; Melendez-Torres, G J

2017-10-01

To systematically review studies of TB treatment experiences in immigrant populations, using Critical Interpretive Synthesis (CIS). On 26 October 2014, MEDLINE, CINAHL, Embase, LILACS, and PsycINFO were systematically searched. Grey literature and reference lists were hand-searched. Initial papers included were restricted to studies of immigrant patient perspectives; after a model was developed, a second set of papers was included to test the emerging theory. Of 1761 studies identified in the search, a total of 29 were included in the synthesis. Using those studies, we developed a model that suggested treatment experiences were strongly related to the way both individuals and societies adjusted to immigration ('acculturation strategies'). Relationships with healthcare workers and immigration policies played particularly significant roles in TB treatment. This review emphasised the roles of repatriation policy and healthcare workers in forming experiences of TB treatment in immigrant populations. © 2017 John Wiley & Sons Ltd.

A Low-Cost, Hands-on Module to Characterize Antimicrobial Compounds Using an Interdisciplinary, Biophysical Approach

PubMed Central

Kaushik, Karishma S.; Kessel, Ashley; Ratnayeke, Nalin; Gordon, Vernita D.

2015-01-01

We have developed a hands-on experimental module that combines biology experiments with a physics-based analytical model in order to characterize antimicrobial compounds. To understand antibiotic resistance, participants perform a disc diffusion assay to test the antimicrobial activity of different compounds and then apply a diffusion-based analytical model to gain insights into the behavior of the active antimicrobial component. In our experience, this module was robust, reproducible, and cost-effective, suggesting that it could be implemented in diverse settings such as undergraduate research, STEM (science, technology, engineering, and math) camps, school programs, and laboratory training workshops. By providing valuable interdisciplinary research experience in science outreach and education initiatives, this module addresses the paucity of structured training or education programs that integrate diverse scientific fields. Its low-cost requirements make it especially suitable for use in resource-limited settings. PMID:25602254

Model Minority Stereotyping, Perceived Discrimination, and Adjustment Among Adolescents from Asian American Backgrounds.

PubMed

Kiang, Lisa; Witkow, Melissa R; Thompson, Taylor L

2016-07-01

The model minority image is a common and pervasive stereotype that Asian American adolescents must navigate. Using multiwave data from 159 adolescents from Asian American backgrounds (mean age at initial recruitment = 15.03, SD = .92; 60 % female; 74 % US-born), the current study targeted unexplored aspects of the model minority experience in conjunction with more traditionally measured experiences of negative discrimination. When examining normative changes, perceptions of model minority stereotyping increased over the high school years while perceptions of discrimination decreased. Both experiences were not associated with each other, suggesting independent forms of social interactions. Model minority stereotyping generally promoted academic and socioemotional adjustment, whereas discrimination hindered outcomes. Moreover, in terms of academic adjustment, the model minority stereotype appears to protect against the detrimental effect of discrimination. Implications of the complex duality of adolescents' social interactions are discussed.

Stress resilience in early marriage: can practice make perfect?

PubMed

Neff, Lisa A; Broady, Elizabeth F

2011-11-01

As all couples experience stressful life events, addressing how couples adapt to stress is imperative for understanding marital development. Drawing from theories of stress inoculation, which suggest that the successful adaptation to moderately stressful events may help individuals develop a resilience to future stress, the current studies examined whether experiences with manageable stressors early in the marriage may serve to make the relationship more resilient to future stress. In Study 1, 61 newlywed couples provided data regarding their stressful life events, relationship resources (i.e., observed problem-solving behaviors), and marital satisfaction at multiple points over 2½ years. Results revealed that among spouses displaying more effective problem-solving behaviors, those who experienced moderate stress during the early months of marriage exhibited fewer future stress spillover effects and reported greater increases in felt efficacy than did spouses who had less experience with early stress. Study 2 examined stress resilience following the transition to parenthood in a new sample of 50 newlywed couples. Again, spouses who experienced moderate stress during the early months of marriage and had good initial relationship resources (i.e., observed support behaviors) reported greater marital adjustment following the transition to parenthood than did spouses who had good initial resources but less prior experience coping with stress. Together, results indicate that entering marriage with better relationship resources may not be sufficient to shield marital satisfaction from the detrimental effects of stress; rather, couples may also need practice in using those resources to navigate manageable stressful events.

Modifying mixing and instability growth through the adjustment of initial conditions in a high-energy-density counter-propagating shear experiment on OMEGA

DOE PAGES

Merritt, E. C.; Doss, F. W.; Loomis, E. N.; ...

2015-06-24

Counter-propagating shear experiments conducted at the OMEGA Laser Facility have been evaluating the effect of target initial conditions, specifically the characteristics of a tracer foil located at the shear boundary, on Kelvin-Helmholtz instability evolution and experiment transition toward nonlinearity and turbulence in the high-energy-density (HED) regime. Experiments are focused on both identifying and uncoupling the dependence of the model initial turbulent length scale in variable-density turbulence models of k-ϵ type on competing physical instability seed lengths as well as developing a path toward fully developed turbulent HED experiments. We present results from a series of experiments controllably and independently varyingmore » two initial types of scale lengths in the experiment: the thickness and surface roughness (surface perturbation scale spectrum) of a tracer layer at the shear interface. We show that decreasing the layer thickness and increasing the surface roughness both have the ability to increase the relative mixing in the system, and thus theoretically decrease the time required to begin transitioning to turbulence in the system. In addition, we also show that we can connect a change in observed mix width growth due to increased foil surface roughness to an analytically predicted change in model initial turbulent scale lengths.« less

Smartphones and health promotion: a review of the evidence.

PubMed

Bert, Fabrizio; Giacometti, Marika; Gualano, Maria Rosaria; Siliquini, Roberta

2014-01-01

Communication via mobile phones has become an essential tool for health professionals. The latest generation of smartphones is comparable to computers, allowing the development of new applications in health field. This paper aims to describe the use of smartphones by health professionals and patients in the field of health promotion. We conducted a bibliographic search through Pubmed. Then, research results were analyzed critically in order to select the best experiences available. All searches were carried out on November 2012 and were not limited by date. Each item from the initial search was reviewed independently by members of the project team. Initial search returned 472 items with PubMed. After the removal of duplicates, 406 items were reviewed by all the members of the project team and 21 articles were identified as specifically centered on health promotion. In the nutrition field there are applications that allow to count calories and keep a food diary or more specific platforms for people with food allergies, while about physical activity many applications suggest exercises with measurement of sports statistics. Some applications deal with lifestyles suggestions and tips. Finally, some positive experiences are reported in the prevention of falls in elderly and of sexually-transmitted diseases. Smartphones are transforming the ways of communication but the lack of monitoring of contents, the digital divide, the confidentiality of data, the exclusion of the health professional from the management of patient, are the main risks related to their use.

Evidence for carboxyl-terminal processing and glycolipid-anchoring of human carcinoembryonic antigen.

PubMed

Takami, N; Misumi, Y; Kuroki, M; Matsuoka, Y; Ikehara, Y

1988-09-05

We have investigated the post-translational modification of carcinoembryonic antigen (CEA) for membrane-anchoring in QGP-1 cells derived from a human pancreatic carcinoma. Pulse-chase experiments with [3H]leucine demonstrated that CEA was initially synthesized as a precursor form with Mr 150,000 having N-linked high-mannose-type oligosaccharides, which was then converted to a mature form with Mr 200,000 containing the complex type sugar chains. The mature protein thus labeled was found to be released from the cell surface by treatment with phosphatidylinositol-specific phospholipase C, suggesting that CEA is a phosphatidylinositol-linked membrane protein. This was confirmed by metabolic incorporation into CEA of 3H-labeled compounds such as ethanolamine, myo-inositol, palmitic acid, and stearic acid. The 3H-labeled fatty acids incorporated were specifically removed from the protein by nitrous acid deamination as well as by phosphatidylinositol-specific phospholipase C treatment. Since the available cDNA sequence predicts that CEA contains a single methionine residue only in its carboxyl-terminal hydrophobic domain, processing of the carboxyl terminus was examined by pulse-chase experiments with [35S]methionine. It was found that CEA with Mr 150,000 was initially labeled with [35S]methionine but its radioactivity was immediately lost with chase. Taken together, these results suggest that CEA is anchored to the membrane by simultaneously occurring proteolysis of the carboxyl terminus and replacement by the glycophospholipid immediately after the synthesis.

Affect intensity and processing fluency of deterrents.

PubMed

Holman, Andrei

2013-01-01

The theory of emotional intensity (Brehm, 1999) suggests that the intensity of affective states depends on the magnitude of their current deterrents. Our study investigated the role that fluency--the subjective experience of ease of information processing--plays in the emotional intensity modulations as reactions to deterrents. Following an induction phase of good mood, we manipulated both the magnitude of deterrents (using sets of photographs with pre-tested potential to instigate an emotion incompatible with the pre-existent affective state--pity) and their processing fluency (normal vs. enhanced through subliminal priming). Current affective state and perception of deterrents were then measured. In the normal processing conditions, the results revealed the cubic effect predicted by the emotional intensity theory, with the initial affective state being replaced by the one appropriate to the deterrent only in participants exposed to the high magnitude deterrence. In the enhanced fluency conditions the emotional intensity pattern was drastically altered; also, the replacement of the initial affective state occurred at a lower level of deterrence magnitude (moderate instead of high), suggesting the strengthening of deterrence emotional impact by enhanced fluency.

African Easterly Waves in 30-day High-Resolution Global Simulations: A Case Study During the 2006 NAMMA Period

NASA Technical Reports Server (NTRS)

Shen, Bo-Wen; Tao, Wei-Kuo; Wu, Man-Li C.

2010-01-01

In this study, extended -range (30 -day) high-resolution simulations with the NASA global mesoscale model are conducted to simulate the initiation and propagation of six consecutive African easterly waves (AEWs) from late August to September 2006 and their association with hurricane formation. It is shown that the statistical characteristics of individual AEWs are realistically simulated with larger errors in the 5th and 6th AEWs. Remarkable simulations of a mean African easterly jet (AEJ) are also obtained. Nine additional 30 -day experiments suggest that although land surface processes might contribute to the predictability of the AEJ and AEWs, the initiation and detailed evolution of AEWs still depend on the accurate representation of dynamic and land surface initial conditions and their time -varying nonlinear interactions. Of interest is the potential to extend the lead time for predicting hurricane formation (e.g., a lead time of up to 22 days) as the 4th AEW is realistically simulated.

Perceptual, not memorial, disruption underlies emotion-induced blindness.

PubMed

Kennedy, Briana L; Most, Steven B

2012-04-01

Emotion-induced blindness refers to impaired awareness of stimuli appearing in the temporal wake of an emotionally arousing stimulus (S. B. Most, Chun, Widders, & Zald, 2005). In previous emotion-induced blindness experiments, participants withheld target responses until the end of a rapid stream of stimuli, even though each target appeared in the middle of the stream. The resulting interval between the targets' offset and participants' initiation of a response leaves open the possibility that emotion-induced blindness reflects a failure to encode or maintain target information in memory rather than a failure of perception. In the present study, participants engaged in a typical emotion-induced blindness task but initiated a response immediately upon seeing each target. Emotion-induced blindness was nevertheless robust. This suggests that emotion-induced blindness is not attributable to the delay between awareness of a target and the initiation of a response, but rather reflects the disruptive impact of emotional distractors on mechanisms driving conscious perception. (PsycINFO Database Record (c) 2012 APA, all rights reserved).

Intracellular Route of Canine Parvovirus Entry

PubMed Central

Vihinen-Ranta, Maija; Kalela, Anne; Mäkinen, Päivi; Kakkola, Laura; Marjomäki, Varpu; Vuento, Matti

1998-01-01

The present study was designed to investigate the endocytic pathway involved in canine parvovirus (CPV) infection. Reduced temperature (18°C) or the microtubule-depolymerizing drug nocodazole was found to inhibit productive infection of canine A72 cells by CPV and caused CPV to be retained in cytoplasmic vesicles as indicated by immunofluorescence microscopy. Consistent with previously published results, these data indicate that CPV enters a host cell via an endocytic route and further suggest that microtubule-dependent delivery of CPV to late endosomes is required for productive infection. Cytoplasmic microinjection of CPV particles was used to circumvent the endocytosis and membrane fusion steps in the entry process. Microinjection experiments showed that CPV particles which were injected directly into the cytoplasm, thus avoiding the endocytic pathway, were unable to initiate progeny virus production. CPV treated at pH 5.0 prior to microinjection was unable to initiate virus production, showing that factors of the endocytic route other than low pH are necessary for the initiation of infection by CPV. PMID:9420290

Social contagion of correct and incorrect information in memory.

PubMed

Rush, Ryan A; Clark, Steven E

2014-01-01

The present study examines how discussion between individuals regarding a shared memory affects their subsequent individual memory reports. In three experiments pairs of participants recalled items from photographs of common household scenes, discussed their recall with each other, and then recalled the items again individually. Results showed that after the discussion. individuals recalled more correct items and more incorrect items, with very small non-significant increases, or no change, in recall accuracy. The information people were exposed to during the discussion was generally accurate, although not as accurate as individuals' initial recall. Individuals incorporated correct exposure items into their subsequent recall at a higher rate than incorrect exposure items. Participants who were initially more accurate became less accurate, and initially less-accurate participants became more accurate as a result of their discussion. Comparisons to no-discussion control groups suggest that the effects were not simply the product of repeated recall opportunities or self-cueing, but rather reflect the transmission of information between individuals.

Large deformation image classification using generalized locality-constrained linear coding.

PubMed

Zhang, Pei; Wee, Chong-Yaw; Niethammer, Marc; Shen, Dinggang; Yap, Pew-Thian

2013-01-01

Magnetic resonance (MR) imaging has been demonstrated to be very useful for clinical diagnosis of Alzheimer's disease (AD). A common approach to using MR images for AD detection is to spatially normalize the images by non-rigid image registration, and then perform statistical analysis on the resulting deformation fields. Due to the high nonlinearity of the deformation field, recent studies suggest to use initial momentum instead as it lies in a linear space and fully encodes the deformation field. In this paper we explore the use of initial momentum for image classification by focusing on the problem of AD detection. Experiments on the public ADNI dataset show that the initial momentum, together with a simple sparse coding technique-locality-constrained linear coding (LLC)--can achieve a classification accuracy that is comparable to or even better than the state of the art. We also show that the performance of LLC can be greatly improved by introducing proper weights to the codebook.

76 FR 76173 - Notice of Submission of Proposed Information Collection to OMB; Transformation Initiative...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-12-06

... DEPARTMENT OF HOUSING AND URBAN DEVELOPMENT [Docket No. FR-5480-N-118] Notice of Submission of Proposed Information Collection to OMB; Transformation Initiative: Natural Experiment Grant Program AGENCY...: Transformation Initiative: Natural Experiment Grant Program. OMB Approval Number: 2528-New. Form Numbers: HUD...

The Archetype of Initiation in Selected Novels of Black Adolescence.

ERIC Educational Resources Information Center

Pettigrew, B. Joye

1972-01-01

This paper discusses several novels written by black American writers that deal with the initiation experiences of young blacks, and should, therefore, appeal to black adolescents. The novels are grouped according to the three stages in the initiation experience of the adolescent: separation; transition; and incorporation. In separation, the…

Evaluation of the metabolic fate of munitions material (TNT & RDX) in plant systems. Initial assessment of plant DNA mutation spectra as a biomarker

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

Leung, F.; Cataldo, D.A.; Fellows, R.J.

1995-09-01

Munitions material can enter the environment as a result of manufacturing activities and field usage. Predictor methodologies, or biomarkers would enhance evaluation of environmental impacts. The goal of this exploratory study deoxyribonucleic acid (DNA) mutation frequency as a biomarker for munitions exposure. The approach e resolution of an effective repetitive sequence probe for the identification of characteristic mutations, and (2) the development of a testing media [a clonal cell line of carrot (Daucus carota) spension cells]. Commercially available probes demonstrated marginal resolution therefore a low-C{sub o}t library was then constructed. Three colonies from the low-C{sub o}t DNA library were screenedmore » and the DNA isolates sequenced. A suspension culture of carrot (Daucus carota) was developed. A mutation spectra experiment was initiated at a 10-mg TNT/L exposure concentration with the attempt to clone over 1500 single TNT-exposed cells. Over the following six months greater than 98% of the initially isolated cells were unable to survive and produce micro calluses. The remaining calli were too few to be statistically significant and the experiment was terminated. The biomarker concept itself remains to be disproved, but the need for large numbers of uniform clones to differentiate true mutations suggest that more direct techniques using whole tissues need to be developed.« less

Inactivation of Mycobacterium avium with free chlorine.

PubMed

Luh, Jeanne; Mariñas, Benito J

2007-07-15

The inactivation kinetics of Mycobacterium avium with free chlorine was characterized by two stages: an initial phase at a relatively fast rate followed by a slower second stage of pseudo first-order kinetics. The inactivation rate of each stage was approximately the same for all experiments performed at a certain condition of pH and temperature; however, variability was observed for the disinfectant exposure at which the transition between the two stages occurred. This variability was not a function of the initial disinfectant concentration, the initial bacterial density, or the bacterial stock. However, the transition to the second stage varied more significantly at high temperatures (30 degrees C), while lower variability was observed at lower temperatures (5 and 20 degrees C). Experiments conducted at pH values in the range of 6-9 revealed that the inactivation of M. avium was primarily due to hypochlorous acid, with little contribution from hypochlorite ion within this pH range. The inactivation kinetics was represented with a two-population model. The activation energies for the resulting pseudo first-order rate constants for the populations with fast and slow kinetics were 100.3 and 96.5 kJ/mol, respectively. The magnitude of these values suggested that for waters of relatively high pH and low temperatures, little inactivation of M. avium would be achieved within treatment plants, providing a seeding source for distribution systems.

Inhibitory effect of natural coumarin compounds, esculetin and esculin, on oxidative DNA damage and formation of aberrant crypt foci and tumors induced by 1,2-dimethylhydrazine in rat colons.

PubMed

Kaneko, Takao; Tahara, Shoichi; Takabayashi, Fumiyo

2007-11-01

The effects of esculetin (6,7-dihydroxycoumarin) and its 6-glycoside, esculin, on 8-oxo-2'-deoxyguanosine (8-oxodG) formation and carcinogenesis induced by a chemical carcinogen, 1,2-dimethylhydrazine (DMH), were examined in the colons of male Fischer 344 rats. Animals were given water containing esculetin or esculin for 7 d before subcutaneous injection of DMH (20 mg/kg body wt), killed 24 h after DMH treatment, and the levels of thiobarbituric acid reactive substances (TBARS) and 8-oxodG in the colons were determined. Both esculetin and esculin suppressed significantly the DMH-induced increases in 8-oxodG and TBARS in rat colon mucosa. We further investigated the modifying effect of esculin intake on the development of DMH-induced colonic aberrant crypt foci (ACF). Animals were given DMH once a week for 4 weeks to induce ACF. They then received water containing esculin ad libitum for 5 weeks (initiation phase) or 11 weeks after DMH treatment (post-initiation phase). Animals in the positive control group received tap water throughout the experiment. At the end of the experiment (16 weeks), the ingestion of esculin during the initiation phase significantly reduced the incidence of gross tumors, the number of ACF per rat and the mean number of AC per focus, while the esculin treatment during the post-initiation phase significantly decreased only the number of ACF per rat. These results suggest that esculin intake has an inhibitory effect on DMH-induced oxidative DNA damage and carcinogenesis in rat colons.

Peer Exclusion During the Pubertal Transition: The Role of Social Competence.

PubMed

Carter, Rona; Halawah, Amira; Trinh, Sarah L

2018-01-01

For some youth, early puberty is accompanied by peer exclusion. Yet early developers may experience less peer exclusion if they have social competence, which would bolster their ability to develop and maintain positive relationships with their peers. Accordingly, the present study tests whether pubertal timing and tempo predicts decrements in children's social competence and whether decrements in social competence account for associations between puberty (timing and tempo) and peer exclusion over time. Longitudinal data were drawn from 1364 families (48% female; 76% White; M = 9.32 years, SD = .48, at Wave 3) who participated in Waves 3-5 (i.e., grades 4-6) of Phase III of the NICHD-SECCYD. The results from latent growth curve models indicated that earlier pubertal timing and more rapid pubertal tempo among girls were associated with high initial levels of peer exclusion. Moreover, mediation analyses revealed that early developers' susceptibility to peer exclusion was associated with their initial level of social competence. In boys, pubertal timing and tempo were not directly associated with peer exclusion; instead, indirect effects of pubertal timing on peer exclusion (intercept, slope) occurred through initial levels of social competence. On average, early developers' who had low levels of social competence also had high initial levels of peer exclusion but experienced decrements in peer exclusion over time. The association between the intercepts for puberty and peer exclusion and the slopes for social competence and peer exclusion were stronger for boys than girls. Overall, our findings suggest that early developers' susceptibility to and experiences of peer exclusion are associated with their development of social competence.

The Design and Development of Staff Wellbeing Initiatives: Staff Stressors, Burnout and Emotional Exhaustion at Children and Young People's Mental Health in Australia.

PubMed

Coates, Dominiek D; Howe, Deborah

2015-11-01

Mental health work presents problems for staff over and above those encountered in other organisations, including other areas of healthcare. Healthcare workers, in particular mental health workers, have poorer job satisfaction and higher job burnout and turnover compared with established norms for other occupational groups. To make sense of why healthcare workers experience high levels of burnout, a strong body of literature points to the emotionally demanding nature of people-work. The negative effects of mental health work on employee health can be mitigated by the provision of appropriate job resources and wellbeing initiatives. As to develop initiatives that appropriately target staff sources of stress and needs, it is important to engage staff in this process. As such, Children and Young People's Mental Health (CYPMH) and headspace Gosford, in Australia, New South Wales (NSW), developed a survey to identify how staff experience and manage the emotional demands of mental health work, what they identify as key stressors and which initiatives they would like to see implemented. Fifty-five staff (response rate of 73 %) completed the survey, and the results suggest that while staff find the work emotionally demanding, they do not appear to be emotionally exhausted and report administrative rather than client issues as their primary concerns. While a strong body of literature identifies the management of emotions in the workplace as a significant cause of stress, organisational stressors such as working in a bureaucratic environment are also important to understanding staff wellbeing.

Effects of practice on tip-of-the-tongue states.

PubMed

Smith, S M; Balfour, S P; Brown, J M

1994-03-01

Tip-of-the-tongue (TOT) states were examined in relation to acquisition manipulations, using named imaginary animals (TOTimals) as targets. High levels of TOT states were found in three experiments. In the first experiment an increase in the duration of initial exposure to target material improved recall and recognition, and reduced the number of unrecalled items not in TOT states (NTOTs), but did not affect TOT levels. In Experiment 2 practice at writing target names, as compared with only reading them, improved recall performance and decreased TOT levels, but did not reduce NTOTs. Experiment 3 replicated the finding that writing during practice reduced TOT states, but did not reduce NTOTs, and also found that more frequent practice trials increased recall without affecting TOT levels. The results suggest that practice writing target names prevents TOT states by strengthening otherwise deficient phonological connections in memory, a deficiency that can cause TOT states when visual-to-lexical connections give only partial access to a target in memory. The results also demonstrate the usefulness of the TOTimal technique for testing effects of acquisition variables on TOT experiences.

Phantom auditory sensation in rats: an animal model for tinnitus.

PubMed

Jastreboff, P J; Brennan, J F; Coleman, J K; Sasaki, C T

1988-12-01

In order to measure tinnitus induced by sodium salicylate injections, 84 pigmented rats, distributed among 14 groups in five experiments, were used in a conditioned suppression paradigm. In Experiment 1, all groups were trained with a conditioned stimulus (CS) consisting of the offset of a continuous background noise. One group began salicylate injections before Pavlovian training, a second group started injections after training, and a control group received daily saline injections. Resistance to extinction was profound when injections started before training, but minimal when initiated after training, which suggests that salicylate-induced effects acquired differential conditioned value. In Experiment 2 we mimicked the salicylate treatments by substituting a 7 kHz tone in place of respective injections, resulting in effects equivalent to salicylate-induced behavior. In a third experiment we included a 3 kHz CS, and again replicated the salicylate findings. In Experiment 4 we decreased the motivational level, and the sequential relation between salicylate-induced effects and suppression training was retained. Finally, no salicylate effects emerged when the visual modality was used. These findings support the demonstration of phantom auditory sensations in animals.

Feature binding in visual short-term memory is unaffected by task-irrelevant changes of location, shape, and color.

PubMed

Logie, Robert H; Brockmole, James R; Jaswal, Snehlata

2011-01-01

Three experiments used a change detection paradigm across a range of study-test intervals to address the respective contributions of location, shape, and color to the formation of bindings of features in sensory memory and visual short-term memory (VSTM). In Experiment 1, location was designated task irrelevant and was randomized between study and test displays. The task was to detect changes in the bindings between shape and color. In Experiments 2 and 3, shape and color, respectively, were task irrelevant and randomized, with bindings tested between location and color (Experiment 2) and location and shape (Experiment 3). At shorter study-test intervals, randomizing location was most disruptive, followed by shape and then color. At longer intervals, randomizing any task-irrelevant feature had no impact on change detection for bindings between features, and location had no special role. Results suggest that location is crucial for initial perceptual binding but loses that special status once representations are formed in VSTM, which operates according to different principles, than do visual attention and perception.

Winning and positive affect can lead to reckless gambling.

PubMed

Cummins, Lori F; Nadorff, Michael R; Kelly, Anita E

2009-06-01

Experiments 1 and 2 examined whether winning versus losing led to reckless betting for real prize money. Experiment 2 also assessed whether positive or negative emotions were linked to such reckless betting. College students were randomly assigned to experience primarily either wins or losses during the rigged first round of a computerized card tournament that had 2 independent rounds. For the second round, participants' chip totals were reset and cards were dealt randomly. In Experiment 1 (N=107), participants in the Initial-Winning, as compared with the Initial-Losing, condition bet more recklessly (i.e., bet too many chips when a loss was likely). Experiment 2 (N=72) again showed that Initial-Winning participants bet significantly more recklessly than did Initial-Losing participants. It also revealed that positive affect was significantly positively correlated with such reckless betting. These findings have implications for understanding how college students, those at an age when they are especially vulnerable to problem gambling, can come to lose more money than they can afford. Initially winning and positive affect when gambling could be risk factors. Copyright (c) 2009 APA, all rights reserved.

Continuity and change?: Exploring reactions to a guided self-management intervention in a randomised controlled trial for IBS with reference to prior experience of managing a long term condition

PubMed Central

Rogers, Anne; Lee, Victoria; Kennedy, Anne

2007-01-01

Self-care interventions are promoted as effective strategies for improving the quality of life and health outcomes for individuals with long-term health conditions. Outcome measures used in evaluations using Randomised Controlled Trials (RCTs) are not designed to consider patients' prior management strategies and experience of illness. Yet the experience of illness literature suggests that adjusting to living with chronic illness, together with broader contextual influences, are likely to be relevant to understanding responses to self-management initiatives. Using group and individual interview data we attempt to illuminate the transposition of IBS from a condition unsatisfactorily managed by medicine to one successfully managed within the life worlds of individuals. If routine embedding of complex interventions depends on the accomplishment of integration and workability in patients' everyday lives then the design and evaluation of such interventions should view participation as part of a process of continuity as well as change. Responses to formal self-management can be extended beyond psychological and other quantitatively measured outcomes. A useful addendum to trial outcomes for self-management education is an understanding of change as being inextricably linked to people's previous attempts to, and experience of, managing long-term conditions. We suggest that the benefits of understanding the prior experience of managing illness and contact with health services include the acceptability and workability of complex interventions in patients' everyday lives. PMID:17316438

Investigating surface chemistry-controlled dolomite precipitation in saline, alkaline, and dilute waters

NASA Astrophysics Data System (ADS)

Yoerg, A.; Roberts, J. A.

2017-12-01

Previous experiments have shown carboxylated organic matter facilitates dolomite precipitation at low temperature (< 80°C) in both modern and ancient seawater geochemistries. The efficacy of this mechanism in alternative chemical environments, particularly those typical of modern dolomitic environments, remains unclear. We investigated this question using a series of batch laboratory experiments ranging in duration from hours to several months. Experiments were conducted using fluids representative of environments where dolomite is found/thought to form in the modern, such as evaporative, alkaline lakes, sabkhas, and dilute mixing zones. Results indicate that while carboxylated organic matter promotes mineral precipitation in a variety of chemistries, the resultant mineralogy is primarily a function solution chemistry (i.e. saturation state). Specifically, our results suggest elevated alkalinity may be required to produce a high-Mg phase. In solutions where alkalinity is scarce, only amorphous carbonate phases form in association with organic matter, contrasting the Mg-bearing crystalline phases that result from highly alkaline solutions. Results of high-alkalinity, short-term experiments suggest that initially amorphous material is rapidly transformed into high and low-Mg phases in the presence of carboxylated organic matter, but that within days this mineralogy evolves. Longer timescales or elevated temperature may be necessary to produce an ordered dolomite phase. Additional results from longer term, steady-state experiments and additional analyses (Raman spectroscopy and tender energy spectroscopy) will shed further light on resultant mineralogy and this mechanism of dolomite precipitation.

Independence and Interdependence: An Analysis of Pre-Service Candidates' Use of Focused Assignments on an Electronic Discussion Forum during the Initial Field Experience

ERIC Educational Resources Information Center

Fisch, Audrey A.; Bennett, Deborah J.

2011-01-01

This article describes a case study using an electronic learning platform for creating an interactive learning community through asynchronous discussion to enhance the initial field experience of secondary math and English teacher candidates enrolled in Field Experience. We identified three problems with the field experience course--lack of…

Health care administrators' perspectives on the role of absorptive capacity for strategic change initiatives: a qualitative study.

PubMed

Kash, Bita A; Spaulding, Aaron; Gamm, Larry; Johnson, Christopher E

2013-01-01

The dimensions of absorptive capacity (ACAP) are defined, and the importance of ACAP is established in the management literature, but the concept has not been applied to health care organizations attempting to implement multiple strategic initiatives. The aim of this study was to test the utility of ACAP by analyzing health care administrators' experiences with multiple strategic initiatives within two health systems. Results are drawn from administrators' assessments of multiple initiatives within two health systems using in-depth personal interviews with a total of 61 health care administrators. Data analysis was performed following deductive qualitative analysis guidelines. Interview transcripts were coded based on the four dimensions of ACAP: acquiring, assimilating, internalizing/transforming, and exploiting knowledge. Furthermore, we link results related to utilization of management resources, including number of key personnel involved and time consumption, to dimensions of ACAP. Participants' description of multiple strategic change initiatives confirmed the importance of the four ACAP dimensions. ACAP can be a useful framework to assess organizational capacity with respect to the organization's ability to concurrently implement multiple strategic initiatives. This capacity specifically revolves around human capital requirements from upper management based on the initiatives' location or stage within the ACAP framework. Strategic change initiatives in health care can be usefully viewed from an ACAP perspective. There is a tendency for those strategic initiatives ranking higher in priority and time consumption to reflect more advanced dimensions of ACAP (assimilate and transform), whereas few initiatives were identified in the ACAP "exploit" dimension. This may suggest that health care leaders tend to no longer identify as strategic initiatives those innovations that have moved to the exploitation stage or that less attention is given to the exploitation elements of a strategic initiative than to the earlier stages.

BRAF Inhibitors: Experience in Thyroid Cancer and General Review of Toxicity

PubMed Central

Cabanillas, M.E.; Patel, A.; Danysh, B. P.; Dadu, R.; Kopetz, S.; Falchook, G.

2014-01-01

The U.S. Food and Drug Administration–approved BRAF inhibitors, vemurafenib and dabrafenib, have demonstrated superior efficacy in patients with BRAF-mutant melanomas but have limited efficacy in BRAF-mutant colorectal cancer. Little is known at this time regarding BRAF inhibitors in thyroid cancer. Initial reports in patients with progressive, radioactive iodine–refractory BRAF-mutant papillary thyroid cancer suggest response rates of approximately 30–40%. In this review, we discuss BRAF inhibitors in the context of thyroid cancer, the toxicities associated with BRAF inhibitors, and the suggested management of those toxicities. The management of vemurafenib and dabrafenib toxicities is applicable across all tumor types and may serve as a practical guide to their use. PMID:25467940

Influence of musical and psychoacoustical training on pitch discrimination.

PubMed

Micheyl, Christophe; Delhommeau, Karine; Perrot, Xavier; Oxenham, Andrew J

2006-09-01

This study compared the influence of musical and psychoacoustical training on auditory pitch discrimination abilities. In a first experiment, pitch discrimination thresholds for pure and complex tones were measured in 30 classical musicians and 30 non-musicians, none of whom had prior psychoacoustical training. The non-musicians' mean thresholds were more than six times larger than those of the classical musicians initially, and still about four times larger after 2h of training using an adaptive two-interval forced-choice procedure; this difference is two to three times larger than suggested by previous studies. The musicians' thresholds were close to those measured in earlier psychoacoustical studies using highly trained listeners, and showed little improvement with training; this suggests that classical musical training can lead to optimal or nearly optimal pitch discrimination performance. A second experiment was performed to determine how much additional training was required for the non-musicians to obtain thresholds as low as those of the classical musicians from experiment 1. Eight new non-musicians with no prior training practiced the frequency discrimination task for a total of 14 h. It took between 4 and 8h of training for their thresholds to become as small as those measured in the classical musicians from experiment 1. These findings supplement and qualify earlier data in the literature regarding the respective influence of musical and psychoacoustical training on pitch discrimination performance.

Building and Sustaining Citywide Afterschool Initiatives: Experiences of the Cross-Cities Network Citywide Afterschool Initiatives.

ERIC Educational Resources Information Center

Hall, Georgia; Harvey, Brooke

This paper highlights the experiences of several citywide after school initiatives from the Cross-Cities Network, describing activities and strategies that contributed to building operational and sustainable citywide delivery of out-of-school time programs. The paper presents evidence of success and notes lessons learned, identifying key elements…

First Steps: Initial Information and Communication Technology (ICT) Events.

ERIC Educational Resources Information Center

Clarke, Alan

This document is intended to assist practitioners who are designing and organizing an initial information and communication technology (ICT) experience for adult learners. Section 1 presents an overview of the initial ICT learning experience. The concept of transferable skills is discussed in the context of ICT in Section 2. Section 3 explains new…

The WIND-HAARP Experiment: Initial Results of High Power Radiowave Interactions with Space Plasmas

DTIC Science & Technology

1997-11-10

Results from the first science experiment with the new HF Active Auroral Research Program ( HAARP ) facility in Alaska are reported. The initial...experiments involved transmission of high frequency waves from HAARP to the NASA/WIND satellite. The objective was to investigate the effects of space

Transcription Analysis of the Myometrium of Labouring and Non-Labouring Women

PubMed Central

Hutchinson, James L.; Hibbert, Nanette; Freeman, Tom C.; Saunders, Philippa T. K.; Norman, Jane E.

2016-01-01

An incomplete understanding of the molecular mechanisms that initiate normal human labour at term seriously hampers the development of effective ways to predict, prevent and treat disorders such as preterm labour. Appropriate analysis of large microarray experiments that compare gene expression in non-labouring and labouring gestational tissues is necessary to help bridge these gaps in our knowledge. In this work, gene expression in 48 (22 labouring, 26 non-labouring) lower-segment myometrial samples collected at Caesarean section were analysed using Illumina HT-12 v4.0 BeadChips. Normalised data were compared between labouring and non-labouring groups using traditional statistical methods and a novel network graph approach. We sought technical validation with quantitative real-time PCR, and biological replication through inverse variance-weighted meta-analysis with published microarray data. We have extended the list of genes suggested to be associated with labour: Compared to non-labouring samples, labouring samples showed apparent higher expression at 960 probes (949 genes) and apparent lower expression at 801 probes (789 genes) (absolute fold change ≥1.2, rank product percentage of false positive value (RP-PFP) <0.05). Although half of the women in the labouring group had received pharmaceutical treatment to induce or augment labour, sensitivity analysis suggested that this did not confound our results. In agreement with previous studies, functional analysis suggested that labour was characterised by an increase in the expression of inflammatory genes and network analysis suggested a strong neutrophil signature. Our analysis also suggested that labour is characterised by a decrease in the expression of muscle-specific processes, which has not been explicitly discussed previously. We validated these findings through the first formal meta-analysis of raw data from previous experiments and we hypothesise that this represents a change in the composition of myometrial tissue at labour. Further work will be necessary to reveal whether these results are solely due to leukocyte infiltration into the myometrium as a mechanism initiating labour, or in addition whether they also represent gene changes in the myocytes themselves. We have made all our data available at www.ebi.ac.uk/arrayexpress/ (accession number E-MTAB-3136) to facilitate progression of this work. PMID:27176052

Endoscopically placed nitinol stents for pediatric tracheal obstruction.

PubMed

Prasad, Mukesh; Bent, John P; Ward, Robert F; April, Max M

2002-11-11

To provide preliminary clinical data regarding endoscopically placed nitinol stents for children with tracheal obstruction as a temporizing measure to allow for trach tube decannulation while awaiting growth to allow for tracheal resection. This case series describes the experiences of two children (ages 5 and 15) who were dependent upon tracheotomy because of acquired tracheal obstruction. Both patients had combined tracheomalacia and tracheal stenosis. After failing tracheoplasty with rib graft augmentation both patients suffered from extensive tracheal disease, which was too long to allow for immediate tracheal resection. Endoscopic placement of nitinol stents in the obstructed tracheal segment using fluoroscopic guidance. All tracheotomy tubes were removed immediately after successful stent deployment with the patient still under general anesthesia. Four stents were placed in total. The first patient's initial stent was too narrow and was, therefore, removed and replaced at a later date with a larger diameter stent. The second patient experienced distal migration of his initial stent requiring stent removal and replacement at a later date. Both patients remain successfully decannulated (follow-up, 25 and 26 months) and are currently living more normal lives as they grow and await tracheal resection. Preliminary use of nitinol stents for pediatric tracheal obstruction has enabled successful decannulation in two children with complicated airways. Our results with this series of patients suggest that nitinol stents can be safely used in children as a temporizing measure until tracheal resection can be safely performed. With this approach children can live free from the hassles of trach care, social isolation and peer ridicule. Limited pediatric experience exists in the literature about nitinol stents. Thus, our experience with stent selection and placement will help others avoid problems encountered in this initial series. Copyright 2002 Elsevier Science Ireland Ltd.

Measuring verbal communication in initial physical therapy encounters.

PubMed

Roberts, Lisa C; Whittle, Christopher T; Cleland, Jennifer; Wald, Mike

2013-04-01

Communication in clinical encounters is vital in ensuring a positive experience and outcome for both patient and clinician. The purpose of this study was to measure verbal communication between physical therapists and patients with back pain during their initial consultation and trial management of the data using a novel, Web-based application. A cross-sectional study was conducted. Nine musculoskeletal physical therapists and 27 patients with back pain participated in this study. Twenty-five initial consultations were observed, audio recorded, and categorized using the Medical Communications Behavior System. Data were managed using Synote, a freely available application enabling synchronization of audio recordings with transcripts and coded notes. In this sample, physical therapists spoke for 49.5% of the encounter and patients for 33.1%. Providers and patients spent little time overtly discussing emotions (1.4% and 0.9%, respectively). More-experienced clinicians used more "history/background probes," more "advice/suggestion," and less "restatement" than less-experienced staff, although they demonstrated a greater prevalence of talking concurrently and interrupting patients (7.6% compared with 2.6%). Although studies measuring actual behavior are considered to be the gold standard, audio recordings do not enable nonverbal behaviors to be recorded. This study investigated a method for measuring the verbal content of clinical encounters in a physical therapy outpatient setting. The study has directly contributed to developing a research-friendly version of the application (i.e., Synote Researcher). Given the pivotal role of communication in ensuring a positive experience and outcome for both patient and provider, investing time in further developing communication skills should be an on-going priority for providers. Further work is needed to explore affective behaviors and the prevalence of interrupting patients, considering differences in sex and provider experience.

Broadening participation in community problem solving: a multidisciplinary model to support collaborative practice and research.

PubMed

Lasker, Roz D; Weiss, Elisa S

2003-03-01

Over the last 40 years, thousands of communities-in the United States and internationally-have been working to broaden the involvement of people and organizations in addressing community-level problems related to health and other areas. Yet, in spite of this experience, many communities are having substantial difficulty achieving their collaborative objective, and many funders of community partnerships and participation initiatives are looking for ways to get more out of their investment. One of the reasons we are in this predicament is that the practitioners and researchers who are interested in community collaboration come from a variety of contexts, initiatives, and academic disciplines, and few of them have integrated their work with experiences or literatures beyond their own domain. In this article, we seek to overcome some of this fragmentation of effort by presenting a multidisciplinary model that lays out the pathways by which broadly participatory processes lead to more effective community problem solving and to improvements in community health. The model, which builds on a broad array of practical experience as well as conceptual and empirical work in multiple fields, is an outgrowth of a joint-learning work group that was organized to support nine communities in the Turning Point initiative. Following a detailed explication of the model, the article focuses on the implications of the model for research, practice, and policy. It describes how the model can help researchers answer the fundamental effectiveness and "how-to" questions related to community collaboration. In addition, the article explores differences between the model and current practice, suggesting strategies that can help the participants in, and funders of, community collaborations strengthen their efforts.

Constraints on the Transfer of Perceptual Learning in Accented Speech

PubMed Central

Eisner, Frank; Melinger, Alissa; Weber, Andrea

2013-01-01

The perception of speech sounds can be re-tuned through a mechanism of lexically driven perceptual learning after exposure to instances of atypical speech production. This study asked whether this re-tuning is sensitive to the position of the atypical sound within the word. We investigated perceptual learning using English voiced stop consonants, which are commonly devoiced in word-final position by Dutch learners of English. After exposure to a Dutch learner’s productions of devoiced stops in word-final position (but not in any other positions), British English (BE) listeners showed evidence of perceptual learning in a subsequent cross-modal priming task, where auditory primes with devoiced final stops (e.g., “seed”, pronounced [si:th]), facilitated recognition of visual targets with voiced final stops (e.g., SEED). In Experiment 1, this learning effect generalized to test pairs where the critical contrast was in word-initial position, e.g., auditory primes such as “town” facilitated recognition of visual targets like DOWN. Control listeners, who had not heard any stops by the speaker during exposure, showed no learning effects. The generalization to word-initial position did not occur when participants had also heard correctly voiced, word-initial stops during exposure (Experiment 2), and when the speaker was a native BE speaker who mimicked the word-final devoicing (Experiment 3). The readiness of the perceptual system to generalize a previously learned adjustment to other positions within the word thus appears to be modulated by distributional properties of the speech input, as well as by the perceived sociophonetic characteristics of the speaker. The results suggest that the transfer of pre-lexical perceptual adjustments that occur through lexically driven learning can be affected by a combination of acoustic, phonological, and sociophonetic factors. PMID:23554598

Effects of obligatory training and prior training experience on attitudes towards performing basic life support: a questionnaire survey.

PubMed

Matsubara, Hiroki; Enami, Miki; Hirose, Keiko; Kamikura, Takahisa; Nishi, Taiki; Takei, Yutaka; Inaba, Hideo

2015-04-01

To determine the effect of Japanese obligatory basic life support training for new driver's license applicants on their willingness to carry out basic life support. We distributed a questionnaire to 9,807 participants of basic life support courses in authorized driving schools from May 2007 to April 2008 after the release of the 2006 Japanese guidelines. The questionnaire explored the participants' willingness to perform basic life support in four hypothetical scenarios: cardiopulmonary resuscitation on one's own initiative; compression-only cardiopulmonary resuscitation following telephone cardiopulmonary resuscitation; early emergency call; and use of an automated external defibrillator. The questionnaire was given at the beginning of the basic life support course in the first 6-month term and at the end in the second 6-month term. The 9,011 fully completed answer sheets were analyzed. The training significantly increased the proportion of respondents willing to use an automated external defibrillator and to perform cardiopulmonary resuscitation on their own initiative in those with and without prior basic life support training experience. It significantly increased the proportion of respondents willing to carry out favorable actions in all four scenarios. In multiple logistic regression analysis, basic life support training and prior training experiences within 3 years were associated with the attitude. The analysis of reasons for unwillingness suggested that the training reduced the lack of confidence in their skill but did not attenuate the lack of confidence in detection of arrest or clinical judgment to initiate a basic life support action. Obligatory basic life support training should be carried out periodically and modified to ensure that participants gain confidence in judging and detecting cardiac arrest.

Coronae as a result of giant magma intrusions in the lithosphere of Venus: insights from laboratory experiments

NASA Astrophysics Data System (ADS)

Galland, Olivier; Polteau, Stephane; Werner, Stephanie C.

2013-04-01

Coronae on the surface of Venus are unique volcano-tectonic structures in the solar systems. Their circular morphology is associated with various topographic signatures, from bell-shape domes, flat-topped plateaus, to uplifted rings surrounding a subsided centre similar to caldera. Their extensive size and associated lava flows erupting from their periphery, indicate that they result from deep processes in the Venus mantle. Understanding their origin is thus essential for unraveling the dynamics of Venus through time. There are several scenarios explaining the formation of coronae, the most popular being the interaction between an upwelling mantle plume and the lithosphere, creating dynamic topography. In this contribution, we propose that coronae can result from the emplacement of giant magma intrusions below the Venus' lithosphere, on the basis of laboratory experiments. The experimental apparatus consists of a square box filled with compacted fine-grained silica flour (model crust), in which a low viscosity vegetable oil (model magma) is injected at constant flow rate. The initial conditions are such that magma initially flows horizontally, forming a sill-like body, to simulate magmatic underplating. During the experiments, oil injection triggers deformation of the model surface, which is monitored periodically using a moiré projection device, producing time series topographic maps of the model surface. Our results show that the surface evolution of the models follows three stages: (1) initial bell-shaped doming occurs above the injection inlet, producing radial open fractures at the model surfaces; (2) the bell-shape dome evolves to a flat-topped plateau, at the rim of which the oil erupts; (3) after the injection stops, the centre of the plateau subsides, and a positive topographic ring surrounding a depression, like a caldera, remains. The collapse of the plateau also generates concentric extensional fractures at the rims of the caldera. After the dynamic experiment, the oil solidifies and we extracted the intrusion, which exhibits a sill-shape, feeding outward circular inclined sheets at its external edges (i.e. a saucer-shaped sill). From a series of experiments in which the depth of injection h was varied, we show that the diameter of the intrusion and its associated topographic structure correlates linearly with h. The three evolutionary stages simulated in the experiments reproduce remarkably well (1) the three main corona morphologies observed on Venus, and (2) their established succession through time. In addition, the relationships between the structures and the oil flow in our experiments are also similar to those observed on Venus. Therefore, our experimental results suggest that corona structures are the result of giant magma intrusions in the lithosphere of Venus. In addition, our experiments suggest that the diameters of coronae are related to the depth of emplacement of the underlying intrusions, which might be controlled by the rheological architecture of the Venus' lithosphere. Therefore, the analysis of the dimensions and morphologies of coronae are likely to provide crucial information of the structure of the lithosphere of Venus.

Direct measurement of asperity contact growth in quartz at hydrothermal conditions

NASA Astrophysics Data System (ADS)

Beeler, N. M.; Hickman, S. H.

2008-12-01

Room-temperature friction and indentation experiments suggest fault strengthening during the interseismic period results from increases in asperity contact area due to solid-state deformation. However, field observations on exhumed fault zones indicate that solution-transport processes, pressure solution, crack healing and contact overgrowth, influence fault zone rheology near the base of the seismogenic zone. Contact overgrowths result from gradients in surface curvature, where material is dissolved from the pore walls, diffuses through the fluid and precipitates at the contact between two asperities, cementing the asperities together without convergence normal to the contact. To determine the mechanisms and kinetics of asperity cementation, we conducted laboratory experiments in which convex and flat lenses prepared from quartz single crystals were pressed together in an externally heated pressure vessel equipped with an optical observation port. Convergence between the two lenses and contact morphology were continuously monitored during these experiments using reflected-light interferometry through a long-working-distance microscope. Contact normal force is constant with an initial effective normal stress of 1.7 MPa. Four single-phase experiments were conducted at temperatures between 350 and 530C at 150 MPa water pressure, along with two controls: one single phase, dry at 425C and one bimaterial (qtz/sapphire) at 425C and 150 MPa water pressure. No contact growth or convergence was observed in either of the controls. For wet single-phase contacts, however, growth was initially rapid and then decreased with time following an inverse squared dependence of contact radius on aperture. No convergence was observed over the duration of these experiments, suggesting that neither significant pressure solution nor crystal plasticity occurred at these stresses and temperatures. The formation of fluid inclusions between the lenses indicate that the contact is not uniformly wetted. The contact is bounded by small regions of high aperture, reflecting local free-face dissolution as the source for the overgrowth, a definitive indication of diffusion-limited growth. Diffusion-limited growth is also consistent with the inverse squared aperture dependence. However, the apparent activation energy is ~125 kJ/mol, much higher than expected for silica diffusion in bulk water; at present we do not have a complete explanation for the high activation energy. When our lab-measured overgrowth rates are extrapolated to the 5 to 30 micron radius contacts inferred from near-field recordings of M-2 sized earthquakes in deep drill holes and mines (i.e., SAFOD and NELSAM), we predict rates of contact area increase that are orders of magnitude faster than seen in dry, room-temperature friction experiments. This suggests that natural strength recovery should be dominated by fluid-assisted processes at hypocentral conditions near the base of the seismogenic zone.

When seconds count: A study of communication variables in the opening segment of emergency calls.

PubMed

Penn, Claire; Koole, Tom; Nattrass, Rhona

2017-09-01

The opening sequence of an emergency call influences the efficiency of the ambulance dispatch time. The greeting sequences in 105 calls to a South African emergency service were analysed. Initial results suggested the advantage of a specific two-part opening sequence. An on-site experiment aimed at improving call efficiency was conducted during one shift (1100 calls). Results indicated reduced conversational repairs and a significant reduction of 4 seconds in mean call length. Implications for systems and training are derived.

How do you approach seizures in the high altitude traveler?

PubMed

Maa, Edward H

2011-01-01

Counseling patients who suffer first-time or break- through seizures can be difficult, particularly when controllable external factors may be contributing to the lowering of their seizure threshold. High altitude as a potential trigger for seizures is a common question in our epilepsy clinics in Colorado, and this article reviews the existing anecdotal literature, presents our local experience with high altitude seizures (HAS), offers possible mechanisms to explain how high altitude may trigger seizures, and suggests an initial work-up and prophylactic strategies for future high altitude exposures.

Exponentially decaying interaction potential of cavity solitons

NASA Astrophysics Data System (ADS)

Anbardan, Shayesteh Rahmani; Rimoldi, Cristina; Kheradmand, Reza; Tissoni, Giovanna; Prati, Franco

2018-03-01

We analyze the interaction of two cavity solitons in an optically injected vertical cavity surface emitting laser above threshold. We show that they experience an attractive force even when their distance is much larger than their diameter, and eventually they merge. Since the merging time depends exponentially on the initial distance, we suggest that the attraction could be associated with an exponentially decaying interaction potential, similarly to what is found for hydrophobic materials. We also show that the merging time is simply related to the characteristic times of the laser, photon lifetime, and carrier lifetime.

Effect of forward speed on the roll damping of three small fishing vessels

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

Haddara, M.R.; Zhang, S.

1994-05-01

An extensive experimental program has been carried out to estimate roll damping parameters for three models of fishing vessels having different hull shapes and moving with forward speed. Roll damping parameters are determined using a novel method. This method combines the energy method and the modulating function method. The effect of forward speed, initial heel angle and the natural frequency on damping is discussed. A modification of Ikeda's formula for lift damping prediction is suggested. The modified formula produces results which are in good agreement with the experiments.

Risk of thromboembolism in women taking ethinylestradiol/drospirenone and other oral contraceptives.

PubMed

Seeger, John D; Loughlin, Jeanne; Eng, P Mona; Clifford, C Robin; Cutone, Jennifer; Walker, Alexander M

2007-09-01

The oral contraceptive ethinylestradiol 0.03 mg/drospirenone 3 mg contains a progestin component that differs from other oral contraceptives. Case reports and prescription event monitoring suggested that ethinylestradiol/drospirenone might be associated with an elevated risk of thromboembolism. We sought to estimate the association between ethinylestradiol/drospirenone and risk of thromboembolism relative to the association among other oral contraceptives. We identified ethinylestradiol/drospirenone initiators and a twofold larger group of other oral contraceptive initiators between June 2001 and June 2004 within a U.S. health insurer database. The comparison group was selected to have demographic and health care characteristics preceding oral contraceptive initiation that were similar to ethinylestradiol/drospirenone initiators. Thromboembolism during the follow-up of the cohorts was identified through claims for medical services, and only medical record-confirmed cases were included in analyses. The primary (as-matched) analysis used proportional hazards regression, whereas a secondary (as-treated) analysis accounted for changes in oral contraceptives during follow-up using Poisson regression. The 22,429 ethinylestradiol/drospirenone initiators and 44,858 other oral contraceptive initiators were followed for an average of 7.6 months, and there were 18 cases of thromboembolism in ethinylestradiol/drospirenone initiators and 39 in the comparators (rate ratio 0.9, 95% confidence interval 0.5-1.6). More than 9,000 women would need to be prescribed oral contraceptives to observe a difference of one case of thromboembolism. Results of the as-treated analysis were similar to those of the as-matched analysis. Ethinylestradiol/drospirenone initiators and initiators of other oral contraceptives are similarly likely to experience thromboembolism. II.

The Association between Sequences of Sexual Initiation and the Likelihood of Teenage Pregnancy

PubMed Central

Reese, Bianka M.; Haydon, Abigail A.; Herring, Amy H.; Halpern, Carolyn T.

2012-01-01

Purpose Few studies have examined the health and developmental consequences, including unintended pregnancy, of different sexual behavior initiation sequences. Some work suggests that engaging in oral-genital sex first may slow the transition to coital activity and lead to more consistent contraception among adolescents. Methods Using logistic regression analysis, we investigated the association between sequences of sexual initiation (i.e., initiating oral-genital or vaginal sex first based on reported ages of first experience) and the likelihood of subsequent teenage pregnancy among 6,069 females who reported vaginal sex before age 20 and participated in Waves I and IV of the National Longitudinal Study of Adolescent Health (Add Health). Results Among females initiating vaginal sex first, 31.4% reported a teen pregnancy. Among females initiating two behaviors at the same age, 20.5% reported a teen pregnancy. Among females initiating oral-genital sex first, 7.9% reported a teen pregnancy. In multivariate models, initiating oral-genital sex first, with a delay of at least one year to vaginal sex, and initiating two behaviors within the same year were each associated with a lower likelihood of adolescent pregnancy, relative to teens who initiated vaginal sex first (OR=0.23, 95% CI (0.15, 0.37) and OR=0.78, 95% CI (0.60, 0.92), respectively). Conclusions How adolescents begin their sexual lives may be differentially related to positive and negative health outcomes. To develop effective pregnancy prevention efforts for teens and ensure programs are relevant to youths’ needs, it is important to consider multiple facets of sexual initiation and their implications for adolescent sexual health and fertility. PMID:23332489

Relations between the single-pass and double-pass transition probabilities in quantum systems with two and three states

NASA Astrophysics Data System (ADS)

Vitanov, Nikolay V.

2018-05-01

In the experimental determination of the population transfer efficiency between discrete states of a coherently driven quantum system it is often inconvenient to measure the population of the target state. Instead, after the interaction that transfers the population from the initial state to the target state, a second interaction is applied which brings the system back to the initial state, the population of which is easy to measure and normalize. If the transition probability is p in the forward process, then classical intuition suggests that the probability to return to the initial state after the backward process should be p2. However, this classical expectation is generally misleading because it neglects interference effects. This paper presents a rigorous theoretical analysis based on the SU(2) and SU(3) symmetries of the propagators describing the evolution of quantum systems with two and three states, resulting in explicit analytic formulas that link the two-step probabilities to the single-step ones. Explicit examples are given with the popular techniques of rapid adiabatic passage and stimulated Raman adiabatic passage. The present results suggest that quantum-mechanical probabilities degrade faster in repeated processes than classical probabilities. Therefore, the actual single-pass efficiencies in various experiments, calculated from double-pass probabilities, might have been greater than the reported values.

Does conflict help or hurt cognitive control? Initial evidence for an inverted U-shape relationship between perceived task difficulty and conflict adaptation.

PubMed

van Steenbergen, Henk; Band, Guido P H; Hommel, Bernhard

2015-01-01

Sequential modulation of congruency effects in conflict tasks indicates that cognitive control quickly adapts to changing task demands. We investigated in four experiments how this behavioral congruency-sequence effect relates to different levels of perceived task difficulty in a flanker and a Stroop task. In addition, online measures of pupil diameter were used as a physiological index of effort mobilization. Consistent with motivational accounts predicting that increased levels of perceived task difficulty will increase effort mobilization only up to a certain limit, reliable dynamic conflict-driven adjustment in cognitive control was only observed when task difficulty was relatively low. Instead, tasks tentatively associated with high levels of difficulty showed no or reversed conflict adaptation. Although the effects could not be linked consistently to effects in self-reported task difficulty in all experiments, regression analyses showed associations between perceived task difficulty and conflict adaptation in some of the experiments, which provides some initial evidence for an inverted U-shape relationship between perceived difficulty and adaptations in cognitive control. Furthermore, high levels of task difficulty were associated with a conflict-driven reduction in pupil dilation, suggesting that pupil dilation can be used as a physiological marker of mental overload. Our findings underscore the importance of developing models that are grounded in motivational accounts of cognitive control.

Analyses and forecasts of a tornadic supercell outbreak using a 3DVAR system ensemble

NASA Astrophysics Data System (ADS)

Zhuang, Zhaorong; Yussouf, Nusrat; Gao, Jidong

2016-05-01

As part of NOAA's "Warn-On-Forecast" initiative, a convective-scale data assimilation and prediction system was developed using the WRF-ARW model and ARPS 3DVAR data assimilation technique. The system was then evaluated using retrospective short-range ensemble analyses and probabilistic forecasts of the tornadic supercell outbreak event that occurred on 24 May 2011 in Oklahoma, USA. A 36-member multi-physics ensemble system provided the initial and boundary conditions for a 3-km convective-scale ensemble system. Radial velocity and reflectivity observations from four WSR-88Ds were assimilated into the ensemble using the ARPS 3DVAR technique. Five data assimilation and forecast experiments were conducted to evaluate the sensitivity of the system to data assimilation frequencies, in-cloud temperature adjustment schemes, and fixed- and mixed-microphysics ensembles. The results indicated that the experiment with 5-min assimilation frequency quickly built up the storm and produced a more accurate analysis compared with the 10-min assimilation frequency experiment. The predicted vertical vorticity from the moist-adiabatic in-cloud temperature adjustment scheme was larger in magnitude than that from the latent heat scheme. Cycled data assimilation yielded good forecasts, where the ensemble probability of high vertical vorticity matched reasonably well with the observed tornado damage path. Overall, the results of the study suggest that the 3DVAR analysis and forecast system can provide reasonable forecasts of tornadic supercell storms.

Does conflict help or hurt cognitive control? Initial evidence for an inverted U-shape relationship between perceived task difficulty and conflict adaptation

PubMed Central

van Steenbergen, Henk; Band, Guido P. H.; Hommel, Bernhard

2015-01-01

Sequential modulation of congruency effects in conflict tasks indicates that cognitive control quickly adapts to changing task demands. We investigated in four experiments how this behavioral congruency-sequence effect relates to different levels of perceived task difficulty in a flanker and a Stroop task. In addition, online measures of pupil diameter were used as a physiological index of effort mobilization. Consistent with motivational accounts predicting that increased levels of perceived task difficulty will increase effort mobilization only up to a certain limit, reliable dynamic conflict-driven adjustment in cognitive control was only observed when task difficulty was relatively low. Instead, tasks tentatively associated with high levels of difficulty showed no or reversed conflict adaptation. Although the effects could not be linked consistently to effects in self-reported task difficulty in all experiments, regression analyses showed associations between perceived task difficulty and conflict adaptation in some of the experiments, which provides some initial evidence for an inverted U-shape relationship between perceived difficulty and adaptations in cognitive control. Furthermore, high levels of task difficulty were associated with a conflict-driven reduction in pupil dilation, suggesting that pupil dilation can be used as a physiological marker of mental overload. Our findings underscore the importance of developing models that are grounded in motivational accounts of cognitive control. PMID:26217287

The role of orthography in the semantic activation of neighbors.

PubMed

Hino, Yasushi; Lupker, Stephen J; Taylor, Tamsen E

2012-09-01

There is now considerable evidence that a letter string can activate semantic information appropriate to its orthographic neighbors (e.g., Forster & Hector's, 2002, TURPLE effect). This phenomenon is the focus of the present research. Using Japanese words, we examined whether semantic activation of neighbors is driven directly by orthographic similarity alone or whether there is also a role for phonological similarity. In Experiment 1, using a relatedness judgment task in which a Kanji word-Katakana word pair was presented on each trial, an inhibitory effect was observed when the initial Kanji word was related to an orthographic and phonological neighbor of the Katakana word target but not when the initial Kanji word was related to a phonological but not orthographic neighbor of the Katakana word target. This result suggests that phonology plays little, if any, role in the activation of neighbors' semantics when reading familiar words. In Experiment 2, the targets were transcribed into Hiragana, a script they are typically not written in, requiring readers to engage in phonological coding. In that experiment, inhibitory effects were observed in both conditions. This result indicates that phonologically mediated semantic activation of neighbors will emerge when phonological processing is necessary in order to understand a written word (e.g., when that word is transcribed into an unfamiliar script). PsycINFO Database Record (c) 2012 APA, all rights reserved.

Two Regimes of Turbulent Fragmentation and the Stellar Initial Mass Function from Primordial to Present-Day Star Formation

NASA Astrophysics Data System (ADS)

Padoan, Paolo; Nordlund, Åke; Kritsuk, Alexei G.; Norman, Michael L.; Li, Pak Shing

2007-06-01

The Padoan and Nordlund model of the stellar initial mass function (IMF) is derived from low-order statistics of supersonic turbulence, neglecting gravity (e.g., gravitational fragmentation, accretion, and merging). In this work, the predictions of that model are tested using the largest numerical experiments of supersonic hydrodynamic (HD) and magnetohydrodynamic (MHD) turbulence to date (~10003 computational zones) and three different codes (Enzo, Zeus, and the Stagger code). The model predicts a power-law distribution for large masses, related to the turbulence-energy power-spectrum slope and the shock-jump conditions. This power-law mass distribution is confirmed by the numerical experiments. The model also predicts a sharp difference between the HD and MHD regimes, which is recovered in the experiments as well, implying that the magnetic field, even below energy equipartition on the large scale, is a crucial component of the process of turbulent fragmentation. These results suggest that the stellar IMF of primordial stars may differ from that in later epochs of star formation, due to differences in both gas temperature and magnetic field strength. In particular, we find that the IMF of primordial stars born in turbulent clouds may be narrowly peaked around a mass of order 10 Msolar, as long as the column density of such clouds is not much in excess of 1022 cm-2.

Veterans in substance abuse treatment program self-initiate box gardening as a stress reducing therapeutic modality.

PubMed

Lehmann, Lauren P; Detweiler, Jonna G; Detweiler, Mark B

2018-02-01

To assess the experiences of a veteran initiated horticultural therapy garden during their 28-day inpatient Substance Abuse Residential Rehabilitation Treatment Program (SARRTP). Retrospective study. Veterans Affairs Medical Center (VAMC), Salem, Virginia, USA INTERVENTIONS: Group interviews with veterans from the last SARRTP classes and individual interviews with VAMC greenhouse staff in summer of 2016. Time spent in garden, frequency of garden visits, types of passive and active garden activities, words describing the veterans' emotional reactions to utilizing the garden. In 3 summer months of 2016, 50 percent of the 56 veterans interviewed visited and interacted with the gardens during their free time. Frequency of visits generally varied from 3 times weekly to 1-2 times a day. Amount of time in the garden varied from 10min to 2h. The veterans engaged in active and/or passive gardening activities during their garden visits. The veterans reported feeling "calm", "serene", and "refreshed" during garden visitation and after leaving the garden. Although data was secured only at the end of the 2016 growing season, interviews of the inpatient veterans revealed that they used their own initiative and resources to continue the horticulture therapy program for 2 successive growing years after the original pilot project ended in 2014. These non-interventionist, therapeutic garden projects suggest the role of autonomy and patient initiative in recovery programs for veterans attending VAMC treatment programs and they also suggest the value of horticulture therapy as a meaningful evidence- based therapeutic modality for veterans. Published by Elsevier Ltd.

Effects of alcohol, initial gambling outcomes, impulsivity, and gambling cognitions on gambling behavior using a video poker task.

PubMed

Corbin, William R; Cronce, Jessica M

2017-06-01

Drinking and gambling frequently co-occur, and concurrent gambling and drinking may lead to greater negative consequences than either behavior alone. Building on prior research on the effects of alcohol, initial gambling outcomes, impulsivity, and gambling cognitions on gambling behaviors using a chance-based (nonstrategic) slot-machine task, the current study explored the impact of these factors on a skill-based (strategic) video poker task. We anticipated larger average bets and greater gambling persistence under alcohol relative to placebo, and expected alcohol effects to be moderated by initial gambling outcomes, impulsivity, and gambling cognitions. Participants (N = 162; 25.9% female) were randomly assigned to alcohol (target BrAC = .08g%) or placebo and were given $10 to wager on a simulated video poker task, which was programmed to produce 1 of 3 initial outcomes (win, breakeven, or lose) before beginning a progressive loss schedule. Despite evidence for validity of the video poker task and alcohol administration paradigm, primary hypotheses were not supported. Individuals who received alcohol placed smaller wagers than participants in the placebo condition, though this effect was not statistically significant, and the direction of effects was reversed in at-risk gamblers (n = 41). These findings contradict prior research and suggest that alcohol effects on gambling behavior may differ by gambling type (nonstrategic vs. strategic games). Interventions that suggest alcohol is universally disinhibiting may be at odds with young adults' lived experience and thus be less effective than those that recognize the greater complexity of alcohol effects. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Effects of alcohol, initial gambling outcomes, impulsivity and gambling cognitions on gambling behavior using a video poker task

PubMed Central

Corbin, William R.; Cronce, Jessica M.

2017-01-01

Drinking and gambling frequently co-occur, and concurrent gambling and drinking may lead to greater negative consequences than either behavior alone. Building on prior research on the effects of alcohol, initial gambling outcomes, impulsivity, and gambling cognitions on gambling behaviors using a chance-based (non-strategic) slot-machine task, the current study explored the impact of these factors on a skill-based (strategic) video poker task. We anticipated larger average bets and greater gambling persistence under alcohol relative to placebo, and expected alcohol effects to be moderated by initial gambling outcomes, impulsivity, and gambling cognitions. Participants (N=162; 25.9% female) were randomly assigned to alcohol (target BrAC = .08 g%) or placebo and were given $10 to wager on a simulated video poker task, which was programmed to produce 1 of 3 initial outcomes (win, breakeven, or lose) before beginning a progressive loss schedule. Despite evidence for validity of the video poker task and alcohol administration paradigm, primary hypotheses were not supported. Individuals who received alcohol placed smaller wagers than participants in the placebo condition, though this effect was not statistically significant, and the direction of effects was reversed in at-risk gamblers (n=41). These findings contradict prior research and suggest that alcohol effects on gambling behavior may differ by gambling type (non-strategic vs. strategic games). Interventions that suggest alcohol is universally disinhibiting may be at odds with young adults’ lived experience and thus be less effective than those that recognize the greater complexity of alcohol effects. PMID:28493742

Role of auxin and protons in plant shoot gravitropism

NASA Technical Reports Server (NTRS)

Rayle, D. L.; Migliaccio, F.; Watson, E.

1982-01-01

Experiments designed to probe the relationship between asymmetric acid efflux and auxin redistribution during gravitropism are reported. Gravistimulation of sunflower hypocotyls results in the retardation of growth on the upper surface and the acceleration of growth on the lower surface relative to a vertically oriented control. Auxin and H(+) both elicit growth over a similarly broad region of the hypocotyl. The correspondence between auxin, H(+), and gravisensitive tissues is consistent with the notion that auxin redistribution may initiate asymmetric acid efflux during gravistimulation. Data are presented showing a redistribution of C-14-IAA and H-3-IAA occurs within 20-30 minutes of gravistimulation. Data on the effects of selected inhibitors of shoot gravitropism are also presented. Taken together, the data suggest that lateral transport of auxin initiates asymmetric acid efflux in gravitropically stimulated shoots.

The role of mesocosm studies in ecological risk analysis

USGS Publications Warehouse

Boyle, Terence P.; Fairchild, James F.

1997-01-01

Mesocosms have been primarily used as research tools for the evaluation of the fate and effects of xenobiotic chemicals at the population, community, and ecosystem levels of biological organization. This paper provides suggestions for future applications of mesocosm research. Attention should be given to the configuration of mesocosm parameters to explicitly study regional questions of ecological interest. The initial physical, chemical, and biological conditions within mesocosms should be considered as factors shaping the final results of experiments. Certain fundamental questions such as the ecological inertia and resilience of systems with different initial ecological properties should be addressed. Researchers should develop closer working relationships with mathematical modelers in linking computer models to the outcomes of mesocosm studies. Mesocosm tests, linked with models, could enable managers and regulators to forecast the regional consequences of chemicals released into the environment.

Multi-model assessment of the impact of soil moisture initialization on mid-latitude summer predictability

NASA Astrophysics Data System (ADS)

Ardilouze, Constantin; Batté, L.; Bunzel, F.; Decremer, D.; Déqué, M.; Doblas-Reyes, F. J.; Douville, H.; Fereday, D.; Guemas, V.; MacLachlan, C.; Müller, W.; Prodhomme, C.

2017-12-01

Land surface initial conditions have been recognized as a potential source of predictability in sub-seasonal to seasonal forecast systems, at least for near-surface air temperature prediction over the mid-latitude continents. Yet, few studies have systematically explored such an influence over a sufficient hindcast period and in a multi-model framework to produce a robust quantitative assessment. Here, a dedicated set of twin experiments has been carried out with boreal summer retrospective forecasts over the 1992-2010 period performed by five different global coupled ocean-atmosphere models. The impact of a realistic versus climatological soil moisture initialization is assessed in two regions with high potential previously identified as hotspots of land-atmosphere coupling, namely the North American Great Plains and South-Eastern Europe. Over the latter region, temperature predictions show a significant improvement, especially over the Balkans. Forecast systems better simulate the warmest summers if they follow pronounced dry initial anomalies. It is hypothesized that models manage to capture a positive feedback between high temperature and low soil moisture content prone to dominate over other processes during the warmest summers in this region. Over the Great Plains, however, improving the soil moisture initialization does not lead to any robust gain of forecast quality for near-surface temperature. It is suggested that models biases prevent the forecast systems from making the most of the improved initial conditions.

Social Incentives for Gender Differences in the Propensity to Initiate Negotiations: Sometimes It Does Hurt to Ask

ERIC Educational Resources Information Center

Bowles, Hannah Riley; Babcock, Linda; Lai, Lei

2007-01-01

Four experiments show that gender differences in the propensity to initiate negotiations may be explained by differential treatment of men and women when they attempt to negotiate. In Experiments 1 and 2, participants evaluated written accounts of candidates who did or did not initiate negotiations for higher compensation. Evaluators penalized…

The Influence of Students' Pre-College Characteristics, High School Experiences, College Expectations, and Initial Enrollment Characteristics on Degree Attainment

ERIC Educational Resources Information Center

Pike, Gary R.; Hansen, Michele J.; Childress, Janice E.

2014-01-01

The present research examined the extent to which pre-college characteristics, high school experiences, college expectations, and initial enrollment characteristics were related to graduation from college. Data from admission applications, the "ACT Compass" survey, and initial enrollment measures for Fall 2004 and Fall 2005 first-time…

Europa: Initial Galileo Geological Observations

USGS Publications Warehouse

Greeley, R.; Sullivan, R.; Klemaszewski, J.; Homan, K.; Head, J. W.; Pappalardo, R.T.; Veverka, J.; Clark, B.E.; Johnson, T.V.; Klaasen, K.P.; Belton, M.; Moore, J.; Asphaug, E.; Carr, M.H.; Neukum, G.; Denk, T.; Chapman, C.R.; Pilcher, C.B.; Geissler, P.E.; Greenberg, R.; Tufts, R.

1998-01-01

Images of Europa from the Galileo spacecraft show a surface with a complex history involving tectonic deformation, impact cratering, and possible emplacement of ice-rich materials and perhaps liquids on the surface. Differences in impact crater distributions suggest that some areas have been resurfaced more recently than others; Europa could experience current cryovolcanic and tectonic activity. Global-scale patterns of tectonic features suggest deformation resulting from non-synchronous rotation of Europa around Jupiter. Some regions of the lithosphere have been fractured, with icy plates separated and rotated into new positions. The dimensions of these plates suggest that the depth to liquid or mobile ice was only a few kilometers at the time of disruption. Some surfaces have also been upwarped, possibly by diapirs, cryomagmatic intrusions, or convective upwelling. In some places, this deformation has led to the development of chaotic terrain in which surface material has collapsed and/or been eroded. ?? 1998 Academic Press.

Cooperative behavior cascades in human social networks

PubMed Central

Fowler, James H.; Christakis, Nicholas A.

2010-01-01

Theoretical models suggest that social networks influence the evolution of cooperation, but to date there have been few experimental studies. Observational data suggest that a wide variety of behaviors may spread in human social networks, but subjects in such studies can choose to befriend people with similar behaviors, posing difficulty for causal inference. Here, we exploit a seminal set of laboratory experiments that originally showed that voluntary costly punishment can help sustain cooperation. In these experiments, subjects were randomly assigned to a sequence of different groups to play a series of single-shot public goods games with strangers; this feature allowed us to draw networks of interactions to explore how cooperative and uncooperative behaviors spread from person to person to person. We show that, in both an ordinary public goods game and in a public goods game with punishment, focal individuals are influenced by fellow group members’ contribution behavior in future interactions with other individuals who were not a party to the initial interaction. Furthermore, this influence persists for multiple periods and spreads up to three degrees of separation (from person to person to person to person). The results suggest that each additional contribution a subject makes to the public good in the first period is tripled over the course of the experiment by other subjects who are directly or indirectly influenced to contribute more as a consequence. These results show experimentally that cooperative behavior cascades in human social networks. PMID:20212120

Microcomputer-Analyzed Initial Rate Kinetics of the Benzene-Enhanced Unfolding of Myoglobin: A Biophysical Chemistry Experiment.

ERIC Educational Resources Information Center

Schuh, Merlyn D.

1988-01-01

Describes a biophysical chemistry experiment that introduces students to globular protein conformation and microcomputer analysis of initial rate data for the unfolding of proteins. Presents background, materials needed and methodology. Uses a visible spectrometer for analysis. Lists educational benefits derived from the experiment. (ML)

Two types of foreshock activities observed on meter-scale laboratory faults: Slow-slip-driven and cascade-up

NASA Astrophysics Data System (ADS)

Yamashita, F.; Fukuyama, E.; Xu, S.; Kawakata, H.; Mizoguchi, K.; Takizawa, S.

2017-12-01

We report two types of foreshock activities observed on meter-scale laboratory experiments: slow-slip-driven type and cascade-up type. We used two rectangular metagabbro blocks as experimental specimens, whose nominal contacting area was 1.5 m long and 0.1 m wide. To monitor stress changes and seismic activities on the fault, we installed dense arrays of 32 triaxial rosette strain gauges and 64 PZT seismic sensors along the fault. We repeatedly conducted experiments with the same pair of rock specimens, causing the evolution of damage on the fault. We focus on two experiments successively conducted under the same loading condition (normal stress of 6.7 MPa and loading rate of 0.01 mm/s) but different initial fault surface conditions; the first experiment preserved the gouge generated from the previous experiment while the second experiment started with all gouge removed. Note that the distribution of gouge was heterogeneous, because we did not make the gouge layer uniform. We observed many foreshocks in both experiments, but found that the b-value of foreshocks was smaller in the first experiment with pre-existing gouge (PEG). In the second experiment without PEG, we observed premonitory slow slip associated with nucleation process preceding most main events by the strain measurements. We also found that foreshocks were triggered by the slow slip at the end of the nucleation process. In the experiment with PEG, on the contrary, no clear premonitory slow slips were found. Instead, foreshock activity accelerated towards the main event, as confirmed by a decreasing b-value. Spatiotemporal distribution of foreshock hypocenters suggests that foreshocks migrated and cascaded up to the main event. We infer that heterogeneous gouge distribution caused stress-concentrated and unstable patches, which impeded stable slow slip but promoted foreshocks on the fault. Further, our results suggest that b-value is a useful parameter for characterizing these observations.

An empirical method for dynamic camouflage assessment

NASA Astrophysics Data System (ADS)

Blitch, John G.

2011-06-01

As camouflage systems become increasingly sophisticated in their potential to conceal military personnel and precious cargo, evaluation methods need to evolve as well. This paper presents an overview of one such attempt to explore alternative methods for empirical evaluation of dynamic camouflage systems which aspire to keep pace with a soldier's movement through rapidly changing environments that are typical of urban terrain. Motivating factors are covered first, followed by a description of the Blitz Camouflage Assessment (BCA) process and results from an initial proof of concept experiment conducted in November 2006. The conclusion drawn from these results, related literature and the author's personal experience suggest that operational evaluation of personal camouflage needs to be expanded beyond its foundation in signal detection theory and embrace the challenges posed by high levels of cognitive processing.

Effects of optokinetic stimulation induced by virtual reality on locomotion: a preliminary study.

PubMed

Ohyama, Seizo; Nishiike, Suetaka; Watanabe, Hiroshi; Matsuoka, Katsunori; Takeda, Noriaki

2008-11-01

Exposure to a virtual environment for 20 min was sufficient to cause adaptive changes in locomotion in healthy subjects, suggesting that virtual environments might improve locomotor deviation in patients with unilateral labyrinthine defects. Postural and locomotor control in patients with unilateral labyrinthine defects deviates towards the lesion side. The aim of this study was to examine whether active locomotion within a virtual environment can increase the functionality of rehabilitation. We examined the effects of optokinetic stimulation produced by a virtual reality environment on ocular movement and locomotor tracks in 10 healthy subjects. During the 20 min experiment, the mean locomotor deviation and the mean frequency and mean amplitude of optokinetic nystagmus during the last period of the experiment were significantly higher than those during the initial period.

An Initial Investigation of Sexual Minority Youth Involvement in School-Based Extracurricular Activities

PubMed Central

Russell, Stephen T.

2012-01-01

Sexual minority youth are at risk for negative school-based experiences and poor academic outcomes. Yet, little is known about their experiences in positive school-based contexts. Using the National Longitudinal Study of Adolescent Health (1,214 sexual minority and 11,427 heterosexual participants), this study compared participation rates in, predictors of, and outcomes associated with three types of school-based extracurricular activities - sports, arts, and school clubs - by sexual orientation and gender. Findings revealed several significant sexual orientation and gender differences in participation rates in school-based sports, clubs, and arts activities. Further, findings suggested that the outcomes associated with extracurricular activity involvement do not differ by sexual orientation and gender; however, predictors of participation in these domains varied across groups. PMID:24187476

Variation in dual-task performance reveals late initiation of speech planning in turn-taking.

PubMed

Sjerps, Matthias J; Meyer, Antje S

2015-03-01

The smooth transitions between turns in natural conversation suggest that speakers often begin to plan their utterances while listening to their interlocutor. The presented study investigates whether this is indeed the case and, if so, when utterance planning begins. Two hypotheses were contrasted: that speakers begin to plan their turn as soon as possible (in our experiments less than a second after the onset of the interlocutor's turn), or that they do so close to the end of the interlocutor's turn. Turn-taking was combined with a finger tapping task to measure variations in cognitive load. We assumed that the onset of speech planning in addition to listening would be accompanied by deterioration in tapping performance. Two picture description experiments were conducted. In both experiments there were three conditions: (1) Tapping and Speaking, where participants tapped a complex pattern while taking over turns from a pre-recorded speaker, (2) Tapping and Listening, where participants carried out the tapping task while overhearing two pre-recorded speakers, and (3) Speaking Only, where participants took over turns as in the Tapping and Speaking condition but without tapping. The experiments differed in the amount of tapping training the participants received at the beginning of the session. In Experiment 2, the participants' eye-movements were recorded in addition to their speech and tapping. Analyses of the participants' tapping performance and eye movements showed that they initiated the cognitively demanding aspects of speech planning only shortly before the end of the turn of the preceding speaker. We argue that this is a smart planning strategy, which may be the speakers' default in many everyday situations. Copyright © 2014 Elsevier B.V. All rights reserved.

The effect of experience on the hunting success of newly emerged spiderlings.

PubMed

Morse

2000-12-01

Initial interactions with prey may affect a predator's subsequent foraging success. With experience, second-instar Misumena vatia spiderlings (Thomisidae) that had recently emerged from their egg sacs oriented faster to fruit flies (Drosophila melanogaster) than näive individuals. Orientation time of these spiderlings decreased rapidly for the first two to three runs (every third day) in a simple laboratory setting, and then remained low and relatively constant. Time to capture a fly also declined initially, but subsequently became extremely variable, increasing prior to moult. Increase in capture time and the failure to capture prey appeared associated with impending moult, rather than satiation. Spiderlings oriented to prey more rapidly at the beginning of the third instar than at the start of the second instar, suggesting that experience still enhanced performance after a moult cycle. Overall capture times at the beginning of the third instar decreased from those at the end of the second instar, but did not differ significantly from the beginning of the second instar, although spiderlings gaining the most biomass had the shortest mean capture times. In a second experiment, time to orient and time to capture prey did not differ in näive, second-instar siblings run 1 and 3 days after emergence from their egg sacs. However, 3-day individuals that had captured prey each day (confiscated before they could feed) oriented faster than näive 3-day-old siblings, but did not differ in the time taken to capture prey. Experience, rather than age or energetic condition, best explains these changes in performance. Copyright 2000 The Association for the Study of Animal Behaviour.

Under the (legal) radar screen: global health initiatives and international human rights obligations

PubMed Central

2012-01-01

Background Given that many low income countries are heavily reliant on external assistance to fund their health sectors the acceptance of obligations of international assistance and cooperation with regard to the right to health (global health obligations) is insufficiently understood and studied by international health and human rights scholars. Over the past decade Global Health Initiatives, like the Global Fund to fight AIDS, Tuberculosis and Malaria (Global Fund) have adopted novel approaches to engaging with stakeholders in high and low income countries. This article explores how this experience impacted on acceptance of the international obligation to (help) fulfil the right to health beyond borders. Methods The authors conducted an extensive review of international human rights law literature, transnational legal process literature, global public health literature and grey literature pertaining to Global Health Initiatives. To complement this desk work and deepen their understanding of how and why different legal norms evolve the authors conducted 19 in-depth key informant interviews with actors engaged with three stakeholders; the European Union, the United States and Belgium. The authors then analysed the interviews through a transnational legal process lens. Results Through according value to the process of examining how and why different legal norms evolve transnational legal process offers us a tool for engaging with the dynamism of developments in global health suggesting that operationalising global health obligations could advance the right to health for all. Conclusions In many low-income countries the health sector is heavily dependent on external assistance to fulfil the right to health of people thus it is vital that policies and tools for delivering reliable, long-term assistance are developed so that the right to health for all becomes more than a dream. Our research suggests that the Global Fund experience offers lessons to build on. PMID:23153090

The effect of DTC advertisement content on belief tenacity: a study of appeals and argument types.

PubMed

Jalnawala, Nekshan; Wilkin, Noel E

2007-03-01

Direct-to-consumer advertising (DTCA) has an influence on patients' perceptions, awareness, and behaviors. Inoculation theory and the model of belief processing provide insights into cognition that stand to increase our understanding of how patients process the information presented in these advertisements and form beliefs about medications. This study was conducted to evaluate the effect of sidedness of appeals and argument types in understanding beliefs that are formed after exposure to advertisements. DTCA and negative experiences were used to study these constructs. A 2 (1-sided vs 2-sided appeals) x 2 (causal vs authoritative arguments) factorial study design was used. A total of 263 undergraduate students were assigned to view 1 of the 4 mock flu-medication advertisements and complete a questionnaire. Subjects were then presented with a negative scenario and were asked to fill out a questionnaire based on the information in the ad and in the negative scenario. The dependent measures included belief change, change in intent to inquire, and standardized price change. Data were analyzed using 2-way analysis of variance. Subjects exposed to 2-sided appeals showed lower belief change, standardized price change, and change in intent to inquire following a negative experience than subjects exposed to 1-sided appeals (P<.05). No significant difference was found between subjects who received causal arguments and those who received authoritative arguments. A significant interaction effect was observed between sidedness of appeal and argument type on initial belief and initial intent to inquire. Some support for aspects of inoculation theory and theory of belief formation was found. The findings suggest that complying with the "fair-balance" requirement may be beneficial to pharmaceutical marketers as 2-sided appeals increase the tenacity of consumers' beliefs. Higher initial belief and intent to inquire when causal arguments are used in 2-sided promotional messages suggest that use of data to substantiate claims in advertisements may result in enhanced beliefs about the merits of advertised medication.

New approaches to the diagnosis and management of laser eye injury

NASA Astrophysics Data System (ADS)

Hacker, Henry D.; Brown, Jeremiah, Jr.; Cheramie, Rachel; Stuck, Bruce E.

2007-02-01

The emergence of high resolution optical coherence tomography (OCT) along with evidence showing beneficial effects of anti-inflammatory drugs for retinal edema and neovascularization suggests a rational plan for the diagnosis and management of patients with acute laser eye injury. We review the results of recent experiments we conducted to evaluate treatment of laser lesions followed by reports of two cases of acute laser eye injury with foveal involvement. The initial presentation of these cases was notable for the lack of significant abnormalities on fluorescein angiography whereas OCT readily disclosed the size and extent of retinal involvement from exposure to laser energy. Prompt referral of these cases resulted in rapid initiation of medical therapy which included a 10-14 day combined course of steroid and non-steroidal anti-inflammatory medication. An initial decrease in Snellen visual acuity of approximately two lines (20/25- to 20/30) was noted on presentation. In both cases, a measurable improvement of visual acuity was noted by two weeks post injury. The use of anti-inflammatory medication may enhance the initial recovery of vision and reduce the likelihood of longer term retinal complications from scarring and neovascularization.

Parafoveal preview during reading: Effects of sentence position

PubMed Central

White, Sarah J.; Warren, Tessa; Reichle, Erik D.

2011-01-01

Two experiments examined parafoveal preview for words located in the middle of sentences and at sentence boundaries. Parafoveal processing was shown to occur for words at sentence-initial, mid-sentence, and sentence-final positions. Both Experiments 1 and 2 showed reduced effects of preview on regressions out for sentence-initial words. In addition, Experiment 2 showed reduced preview effects on first-pass reading times for sentence-initial words. These effects of sentence position on preview could result from reduced parafoveal processing for sentence-initial words, or other processes specific to word reading at sentence boundaries. In addition to the effects of preview, the experiments also demonstrate variability in the effects of sentence wrap-up on different reading measures, indicating that the presence and time course of wrap-up effects may be modulated by text-specific factors. We also report simulations of Experiment 2 using version 10 of E-Z Reader (Reichle, Warren, & McConnell, 2009), designed to explore the possible mechanisms underlying parafoveal preview at sentence boundaries. PMID:21500948

Chemistry of fuel deposits and sediments and their predursors

NASA Technical Reports Server (NTRS)

Mayo, F. R.; Lan, B. Y.; Buttrill, S. E., Jr.; St.john, G. A.

1984-01-01

The mechanism of solid deposit formation on hot engine parts from turbine fuels is investigated. Deposit formation is associated with oxidation of the hydrocarbon fuel. Therefore, oxidation rates and soluble gum formation were measured for several jet turbine fuels and pure hydrocarbon mixtures. Experiments were performed at 130 C using thermal initiation and at 100 C using ditertiary butyl peroxide as a chemical initiator. Correlation of the data shows that the ratio of rate of oxidation to rate of gum formation for a single fuel is not much affected by experimental conditions, even though there are differences in the abilities of different hydrocarbons to initiate and continue the oxidation. This indicates a close association of gum formation with the oxidation process. Oxidations of n-dodecane, tetralin and the more unstable jet fuels are autocatalytic, while those of 2-ethylnaphthalene and a stable jet fuel are self-retarding. However, the ratio of oxidation rate to gum formation rate appear to be nearly constant for each substrate. The effect of oxygen pressure on gum and oxidation formation was also studied. Dependence of gum formation on the concentration of initiator at 100 C is discussed and problems for future study are suggested.

The Effectiveness of Couple and Individual Relationship Education: Distress as a Moderator.

PubMed

Carlson, Ryan G; Rappleyea, Damon L; Daire, Andrew P; Harris, Steven M; Liu, Xiaofeng

2017-03-01

Current literature yields mixed results about the effectiveness of relationship education (RE) with low-income participants and those who experience a high level of individual or relational distress. Scholars have called for research that examines whether initial levels of distress act as a moderator of RE outcomes. To test whether initial levels of relationship and/or individual distress moderate the effectiveness of RE, this study used two samples, one of couples who received couple-oriented relationship education with their partner (n = 192 couples) and one of individuals in a relationship who received individual-oriented RE by themselves (n = 60 individuals). We delivered RE in a community-based setting serving primarily low-income participants. For those attending with a partner, there was a significant interaction between gender, initial distress, and time. Findings indicate that women who were relationally distressed before RE reported the largest pre-postgains. Those who attended an individual-oriented RE program reported significant decreases in individual distress from pre to post, but no significant relationship gains. Findings also suggest that initial levels of distress did not moderate the effectiveness of individual-oriented RE. © 2015 Family Process Institute.

What Can a Hypnotic Induction Do?

PubMed

Woody, Erik; Sadler, Pamela

2016-10-01

In contrast to how recent definitions of hypnosis describe the induction, a work-sample perspective is advocated that characterizes the induction as an initial, stage-setting phase encompassing everything in a hypnotic session up to the first hypnotic suggestion of particular relevance to the therapeutic or research goals at hand. Four major ways are then discussed in which the induction could affect subsequent hypnotic responses: It may provide information about how subsequent behaviors are to be enacted; it may provide cues about the nature of the interpersonal interaction to be expected in hypnosis; it may provide meta-suggestions, defined as suggestive statements intended to enhance responses to subsequent hypnotic suggestions; and it may provide a clear transition to help allow new behaviors and experiences to emerge. Several ideas for future research are advanced, such as mapping hypnosis style onto the interpersonal circumplex, evaluating whether attentional-state changes measured at the end of the induction actually mediate subsequent hypnotic responsiveness, and systematically examining the impact of ritual-like aspects of inductions.

Recruitment of private practices for primary care research: experience in a preventive services clinical trial.

PubMed

McBride, P E; Massoth, K M; Underbakke, G; Solberg, L I; Beasley, J W; Plane, M B

1996-10-01

Recruitment of community primary care practices for studies to improve health service delivery is important to many health care organizations. Prior studies have focused on individual physician recruitment or academic settings. This descriptive study evaluated the efficiency and utility of three different recruitment methods to encourage community practice participation in a preventive services research trial. Primary care practices in four midwestern states were recruited using different sources for initial mailings (physician lists, practice lists, and a managed care organization's primary care network) and different recruiting methods. Outcome measures included response rates, participation rates, and comparative costs of each method. Of the 86 eligible practices contacted, 52 (60%) consented to participate. Mailing to individual physicians was the most cumbersome and expensive method and had the lowest response rate. Initial contacts with practice medical directors increased the participation rate substantially, and practice recruitment meetings improved both study participation and practice-project communication. Experience with these three methods suggests that the most efficient way to recruit practices for participation in a preventive services research trial involves targeted mailings and phone calls to medical directors, followed by on-site practice meetings.

Evolution of wear and friction along experimental faults

USGS Publications Warehouse

Boneh, Yeval; Chang, Jefferson C.; Lockner, David A.; Reches, Zeev

2014-01-01

We investigate the evolution of wear and friction along experimental faults composed of solid rock blocks. This evolution is analyzed through shear experiments along five rock types, and the experiments were conducted in a rotary apparatus at slip velocities of 0.002–0.97 m/s, slip distances from a few millimeters to tens of meters, and normal stress of 0.25–6.9 MPa. The wear and friction measurements and fault surface observations revealed three evolution phases: A) An initial stage (slip distances <50 mm) of wear by failure of isolated asperities associated with roughening of the fault surface; B) a running-in stage of slip distances of 1–3 m with intense wear-rate, failure of many asperities, and simultaneous reduction of the friction coefficient and wear-rate; and C) a steady-state stage that initiates when the fault surface is covered by a gouge layer, and during which both wear-rate and friction coefficient maintain quasi-constant, low levels. While these evolution stages are clearly recognizable for experimental faults made from bare rock blocks, our analysis suggests that natural faults “bypass” the first two stages and slip at gouge-controlled steady-state conditions.

All of the above: When multiple correct response options enhance the testing effect.

PubMed

Bishara, Anthony J; Lanzo, Lauren A

2015-01-01

Previous research has shown that multiple choice tests often improve memory retention. However, the presence of incorrect lures often attenuates this memory benefit. The current research examined the effects of "all of the above" (AOTA) options. When such options are correct, no incorrect lures are present. In the first three experiments, a correct AOTA option on an initial test led to a larger memory benefit than no test and standard multiple choice test conditions. The benefits of a correct AOTA option occurred even without feedback on the initial test; for both 5-minute and 48-hour retention delays; and for both cued recall and multiple choice final test formats. In the final experiment, an AOTA question led to better memory retention than did a control condition that had identical timing and exposure to response options. However, the benefits relative to this control condition were similar regardless of the type of multiple choice test (AOTA or not). Results suggest that retrieval contributes to multiple choice testing effects. However, the extra testing effect from a correct AOTA option, rather than being due to more retrieval, might be due simply to more exposure to correct information.

Does laser-driven heat front propagation depend on material microstructure?

NASA Astrophysics Data System (ADS)

Colvin, J. D.; Matsukuma, H.; Fournier, K. B.; Yoga, A.; Kemp, G. E.; Tanaka, N.; Zhang, Z.; Kota, K.; Tosaki, S.; Ikenouchi, T.; Nishimura, H.

2016-10-01

We showed earlier that the laser-driven heat front propagation velocity in low-density Ti-silica aerogel and TiO2 foam targets was slower than that simulated with a 2D radiation-hydrodynamics code incorporating an atomic kinetics model in non-LTE and assuming initially homogeneous material. Some theoretical models suggest that the heat front is slowed over what it would be in a homogeneous medium by the microstructure of the foam. In order to test this hypothesis we designed and conducted a comparison experiment on the GEKKO laser to measure heat front propagation velocity in two targets, one an Ar/CO2 gas mixture and the other a TiO2 foam, that had identical initial densities and average ionization states. We found that the heat front traveled about ten times faster in the gas than in the foam. We present the details of the experiment design and a comparison of the data with the simulations. This work was performed under the auspices of the U.S. Department of Energy by LLNL under Contract No. DE-AC52-07NA27344, and the joint research project of ILE Osaka U. (contract Nos. 2014A1-04 and 2015A1-02).

Plasma Density Effects on Toroidal Flow Stabilization of Edge Localized Modes

NASA Astrophysics Data System (ADS)

Cheng, Shikui; Zhu, Ping; Banerjee, Debabrata

2016-10-01

Recent EAST experiments have demonstrated mitigation and suppression of edge localized modes (ELMs) with toroidal rotation flow in higher collisionality regime, suggesting potential roles of plasma density. In this work, the effects of plasma density on the toroidal flow stabilization of the high- n edge localized modes have been extensively studied in linear calculations for a circular-shaped limiter H-mode tokamak, using the initial-value extended MHD code NIMROD. In the single MHD model, toroidal flow has a weak stabilizing effects on the high- n modes. Such a stabilization, however, can be significantly enhanced with the increase in plasma density. Furthermore, our calculations show that the enhanced stabilization of high- n modes from toroidal flow with higher edge plasma density persists in the 2-fluid MHD model. These findings may explain the ELM mitigation and suppression by toroidal rotation in higher collisionality regime due to the enhancement of plasma density obtained in EAST experiment. Supported by the National Magnetic Confinement Fusion Program of China under Grant Nos. 2014GB124002 and 2015GB101004, the 100 Talent Program and the President International Fellowship Initiative of Chinese Academy of Sciences.

The role of sensorimotor processes in social group contagion.

PubMed

Cracco, Emiel; Brass, Marcel

2018-06-01

Although it is well known that action observation triggers an imitative response, not much is known about how these responses develop as a function of group size. Research on social contagion suggests that imitative tendencies initially increase but then stabilize as groups become larger. However, these findings have mainly been explained in terms of interpretative processes. Across seven experiments (N = 322), the current study investigated the contribution of sensorimotor processes to social group contagion by looking at the relation between group size and automatic imitation in a task that involved minimal interpretation. The results of Experiments 1-2 revealed that automatic imitation increased with group size according to an asymptotic curve on congruent trials but a linear curve on incongruent trials. The results of Experiments 3-7 showed that the asymptote on congruent trials disappeared when no control was needed, namely in the absence of incongruent trials. This suggests that the asymptote in the relation between group size and automatic imitation can be explained in terms of strategic control mechanisms that aim to prevent unintended imitative responses. The findings of the current study are in close correspondence with previous research in the social domain and as such support the hypothesis that sensorimotor processes contribute to the relation between group size and social contagion. Copyright © 2018 Elsevier Inc. All rights reserved.

Measurement of the energy dependence of X-ray-induced decomposition of potassium chlorate.

PubMed

Pravica, Michael; Bai, Ligang; Sneed, Daniel; Park, Changyong

2013-03-21

We report the first measurements of the X-ray induced decomposition of KClO3 as a function of energy in two experiments. KClO3 was pressurized to 3.5 GPa and irradiated with monochromatic synchrotron X-rays ranging in energy from 15 to 35 keV in 5 keV increments. A systematic increase in the decomposition rate as the energy was decreased was observed, which agrees with the 1/E(3) trend for the photoelectric process, except at the lowest energy studied. A second experiment was performed to access lower energies (10 and 12 keV) using a beryllium gasket; suggesting an apparent resonance near 15 keV or 0.83 Ǻ maximizing the chemical decomposition rate. A third experiment was performed using KIO3 to ascertain the anionic dependence of the decomposition rate, which was observed to be far slower than in KClO3, suggesting that the O-O distance is the critical factor in chemical reactions. These results will be important for more efficiently initiating chemical decomposition in materials using selected X-ray wavelengths that maximize decomposition to aid useful hard X-ray-induced chemistry and contribute understanding of the mechanism of X-ray-induced decomposition of the chlorates.

Online interpretation of scalar quantifiers: insight into the semantics-pragmatics interface.

PubMed

Huang, Yi Ting; Snedeker, Jesse

2009-05-01

Scalar implicature has served as a test case for exploring the relations between semantic and pragmatic processes during language comprehension. Most studies have used reaction time methods and the results have been variable. In these studies, we use the visual-world paradigm to investigate implicature. We recorded participants' eye movements during commands like "Point to the girl that has some of the socks" in the presence of a display in which one girl had two of four socks and another had three of three soccer balls. These utterances contained an initial period of ambiguity in which the semantics of some was compatible with both characters. This ambiguity could be immediately resolved by a pragmatic implicature which would restrict some to a proper subset. Instead in Experiments 1 and 2, we found that participants were substantially delayed, suggesting a lag between semantic and pragmatic processing. In Experiment 3, we examined interpretations of some when competitors were inconsistent with the semantics (girl with socks vs. girl with no socks). We found quick resolution of the target, suggesting that previous delays were specifically linked to pragmatic analysis.

Social Regulation of Leukocyte Homeostasis: The Role of Glucocorticoid Sensitivity

PubMed Central

Cole, Steve W.

2010-01-01

Recent small-scale genomics analyses suggest that physiologic regulation of pro-inflammatory gene expression by endogenous glucocorticoids may be compromised in individuals who experience chronic social isolation. This could potentially contribute to the elevated prevalence of inflammation-related disease previously observed in social isolates. The present study assessed the relationship between leukocyte distributional sensitivity to glucocorticoid regulation and subjective social isolation in a large population-based sample of older adults. Initial analyses confirmed that circulating neutrophil percentages were elevated, and circulating lymphocyte and monocyte percentages were suppressed, in direct proportion to circulating cortisol levels. However, leukocyte distributional sensitivity to endogenous glucocorticoids was abrogated in individuals reporting either occasional or frequent experiences of subjective social isolation. This finding held in both nonparametric univariate analyses and in multivariate linear models controlling for a variety of biological, social, behavioral, and psychological confounders. The present results suggest that social factors may alter immune cell sensitivity to physiologic regulation by the hypothalamic-pituitary-adrenal axis in ways that could ultimately contribute to the increased physical health risks associated with social isolation. PMID:18394861

The Year-Two Experiment: Exploring Teachers' Experiences of a 1:1 Technology Initiative

ERIC Educational Resources Information Center

Uy, Jan Michael

2017-01-01

This study examined the impact of 1:1 device initiatives in U.S. education K-12 school districts. Specifically, the problem addressed in this research was that studies of the second year of 1:1 technology programs in K-12 school districts had documented challenges among teachers with this change initiative leading to discontent and even…

Talking to Strangers--A Sociolinguistic Experiment: Variation in Initial Dyadic Interactions between Spanish-Speakers in Early 21st Century Buenos Aires, Argentina

ERIC Educational Resources Information Center

Dziugis, Mary Ann

2010-01-01

What are the chances of a dyad of Spanish-speaking strangers using informal address in casual, initial interactions in Buenos Aires, Argentina, today? To discover the pattern(s) of contemporary address, the Principal Investigator (PI) conducted a sociolinguistic experiment focusing on strangers' initial interactions to minimize the influence of…

The experience of initiating injection drug use and its social context: a qualitative systematic review and thematic synthesis.

PubMed

Guise, Andy; Horyniak, Danielle; Melo, Jason; McNeil, Ryan; Werb, Dan

2017-12-01

Understanding the experience of initiating injection drug use and its social contexts is crucial to inform efforts to prevent transitions into this mode of drug consumption and support harm reduction. We reviewed and synthesized existing qualitative scientific literature systematically to identify the socio-structural contexts for, and experiences of, the initiation of injection drug use. We searched six databases (Medline, Embase, PsychINFO, CINAHL, IBSS and SSCI) systematically, along with a manual search, including key journals and subject experts. Peer-reviewed studies were included if they qualitatively explored experiences of or socio-structural contexts for injection drug use initiation. A thematic synthesis approach was used to identify descriptive and analytical themes throughout studies. From 1731 initial results, 41 studies reporting data from 1996 participants were included. We developed eight descriptive themes and two analytical (higher-order) themes. The first analytical theme focused on injecting initiation resulting from a social process enabled and constrained by socio-structural factors: social networks and individual interactions, socialization into drug-using identities and choices enabled and constrained by social context all combine to produce processes of injection initiation. The second analytical theme addressed pathways that explore varying meanings attached to injection initiation and how they link to social context: seeking pleasure, responses to increasing tolerance to drugs, securing belonging and identity and coping with pain and trauma. Qualitative research shows that injection drug use initiation has varying and distinct meanings for individuals involved and is a dynamic process shaped by social and structural factors. Interventions should therefore respond to the socio-structural influences on injecting drug use initiation by seeking to modify the contexts for initiation, rather than solely prioritizing the reduction of individual harms through behavior change. © 2017 Society for the Study of Addiction.

Direct measurement of asperity contact growth in quartz at hydrothermal conditions

USGS Publications Warehouse

Beeler, Nicholas M.; Hickman, Stephen H.

2015-01-01

Earthquake recurrence requires interseismic fault restrengthening which results from solid state deformation in room-temperature friction and indentation experiments. In contrast exhumed fault zones show solution-transport processes such as pressure solution and contact overgrowths influence fault zone properties . In the absence of fluid flow, overgrowths are driven by gradients in surface curvature where material is dissolved, diffuses, and precipitates at the contact without convergence normal to the contact. To determine the rate of overgrowth for quartz, we conducted single contact experiments in an externally heated pressure vessel. Convergence was continuously monitored using reflected-light interferometry through a long-working-distance microscope. Contact normal force was constant with an initial effective normal stress of 1.7 MPa, temperature was between 350 and 530{degree sign}C, and water pressure was constant at 150 MPa. Two control experiments were conducted: one dry at 425{degree sign}C and one bi-material (sapphire) at 425{degree sign}C and 150 MPa water pressure. No contact growth or convergence was observed in the controls. For wet single-phase contacts, growth was initially rapid and then decreased with time. No convergence was observed. Fluid inclusions indicate that the contact is not uniformly wetted. The contact is bounded by small regions of high aperture, reflecting local free-face dissolution as the source for the overgrowth. The apparent activation energy is ~125 kJ/mol. Extrapolation predicts rates of contact area increase orders of magnitude faster than in dry, room-temperature and hydrothermal friction experiments, suggesting that natural strength recovery near the base of the seismogenic zone could be dominated by contact overgrowth.

Do initial conditions matter? A comparison of model climatologies generated from different initial states

NASA Technical Reports Server (NTRS)

Spar, J.; Cohen, C.; Wu, P.

1981-01-01

A coarse mesh (8 by 10) 7 layer global climate model was used to compute 15 months of meteorological history in two perpetual January experiments on a water planet (without continents) with a zonally symmetric climatological January sea surface temperature field. In the first of the two water planet experiments the initial atmospheric state was a set of zonal mean values of specific humidity, temperature, and wind at each latitude. In the second experiment the model was initialized with globally uniform mean values of specific humidity and temperature on each sigma level surface, constant surface pressure (1010 mb), and zero wind everywhere. A comparison was made of the mean January climatic states generated by the two water planet experiments. The first two months of each 15 January run were discarded, and 13 month averages were computed from months 3 through 15.

Target objects defined by a conjunction of colour and shape can be selected independently and in parallel.

PubMed

Jenkins, Michael; Grubert, Anna; Eimer, Martin

2017-11-01

It is generally assumed that during search for targets defined by a feature conjunction, attention is allocated sequentially to individual objects. We tested this hypothesis by tracking the time course of attentional processing biases with the N2pc component in tasks where observers searched for two targets defined by a colour/shape conjunction. In Experiment 1, two displays presented in rapid succession (100 ms or 10 ms SOA) each contained a target and a colour-matching or shape-matching distractor on opposite sides. Target objects in both displays elicited N2pc components of similar size that overlapped in time when the SOA was 10 ms, suggesting that attention was allocated in parallel to both targets. Analogous results were found in Experiment 2, where targets and partially matching distractors were both accompanied by an object without target-matching features. Colour-matching and shape-matching distractors also elicited N2pc components, and the target N2pc was initially identical to the sum of the two distractor N2pcs, suggesting that the initial phase of attentional object selection was guided independently by feature templates for target colour and shape. Beyond 230 ms after display onset, the target N2pc became superadditive, indicating that attentional selection processes now started to be sensitive to the presence of feature conjunctions. Results show that independent attentional selection processes can be activated in parallel by two target objects in situations where these objects are defined by a feature conjunction.

Translating and testing the ENABLE: CHF-PC concurrent palliative care model for older adults with heart failure and their family caregivers.

PubMed

Dionne-Odom, J Nicholas; Kono, Alan; Frost, Jennifer; Jackson, Lisa; Ellis, Daphne; Ahmed, Ali; Azuero, Andres; Bakitas, Marie

2014-09-01

Heart failure (HF) and palliative care (PC) organizations recommend early PC to improve the quality of life of patients living with HF. We conducted a two-phase formative evaluation study to translate a cancer-focused concurrent PC intervention into one that would be appropriate for rural-dwelling adults with New York Heart Association Class III-IV HF and their primary caregivers. Phase I: We tailored the intervention for an HF population via literature review, expert consultation, and clinician (N=15) small group interviews. Phase II: We enrolled 11 patient/caregiver dyads to assess intervention feasibility and satisfaction. We assessed participants' experiences and satisfaction after session/week three and session/week six via digitally recorded interviews. Clinician and participant interviews were transcribed and content analyzed. Outcome measures were evaluated for completion rates and effect sizes. Phase I: Clinicians described barriers to initiating PC in HF, triggers for initiating PC, and suggestions for intervention improvement. Phase II: Participants were able to complete the majority of study sessions, measures, and interviews. Satisfaction interviews revealed the content to be relevant and comprehensive in addressing HF patient and caregiver primary concerns; however, participants unanimously suggested making the intervention available earlier in the illness trajectory. Efficacy measures demonstrated small to medium effect sizes. We tailored and demonstrated feasibility of providing an early, concurrent palliative care intervention to patients with advanced HF and their caregivers. Based on this experience we are now conducting an efficacy trial in a racially diverse sample.

Inhibition of voluntary saccadic eye movement commands by abrupt visual onsets.

PubMed

Edelman, Jay A; Xu, Kitty Z

2009-03-01

Saccadic eye movements are made both to explore the visual world and to react to sudden sensory events. We studied the ability for humans to execute a voluntary (i.e., nonstimulus-driven) saccade command in the face of a suddenly appearing visual stimulus. Subjects were required to make a saccade to a memorized location when a central fixation point disappeared. At varying times relative to fixation point disappearance a visual distractor appeared at a random location. When the distractor appeared at locations distant from the target virtually no saccades were initiated in a 30- to 40-ms interval beginning 70-80 ms after appearance of the distractor. If the distractor was presented slightly earlier relative to saccade initiation then saccades tended to have smaller amplitudes, with velocity profiles suggesting that the distractor terminated them prematurely. In contrast, distractors appearing close to the saccade target elicited express saccade-like movements 70-100 ms after their appearance, although the saccade endpoint was generally scarcely affected by the distractor. An additional experiment showed that these effects were weaker when the saccade was made to a visible target in a delayed task and still weaker when the saccade itself was made in response to the abrupt appearance of a visual stimulus. A final experiment revealed that the effect is smaller, but quite evident, for very small stimuli. These results suggest that the transient component of a visual response can briefly but almost completely suppress a voluntary saccade command, but only when the stimulus evoking that response is distant from the saccade goal.

Ideals as Anchors for Relationship Experiences

PubMed Central

Frye, Margaret; Trinitapoli, Jenny

2016-01-01

Research on young-adult sexuality in sub-Saharan Africa typically conceptualizes sex as an individual-level risk behavior. We introduce a new approach that connects the conditions surrounding the initiation of sex with subsequent relationship well-being, examines relationships as sequences of interdependent events, and indexes relationship experiences to individually held ideals. New card-sort data from southern Malawi capture young women’s relationship experiences and their ideals in a sequential framework. Using optimal matching, we measure the distance between ideal and experienced relationship sequences to (1) assess the associations between ideological congruence and perceived relationship well-being, (2) compare this ideal-based approach to other experience-based alternatives, and (3) identify individual- and couple-level correlates of congruence between ideals and experiences in the romantic realm. We show that congruence between ideals and experiences conveys relationship well-being along four dimensions: expressions of love and support, robust communication habits, perceived biological safety, and perceived relationship stability. We further show that congruence is patterned by socioeconomic status and supported by shared ideals within romantic dyads. We argue that conceiving of ideals as anchors for how sexual experiences are manifest advances current understandings of romantic relationships, and we suggest that this approach has applications for other domains of life. PMID:27110031

Effects of laser power density and initial grain size in laser shock punching of pure copper foil

NASA Astrophysics Data System (ADS)

Zheng, Chao; Zhang, Xiu; Zhang, Yiliang; Ji, Zhong; Luan, Yiguo; Song, Libin

2018-06-01

The effects of laser power density and initial grain size on forming quality of holes in laser shock punching process were investigated in the present study. Three different initial grain sizes as well as three levels of laser power densities were provided, and then laser shock punching experiments of T2 copper foil were conducted. Based upon the experimental results, the characteristics of shape accuracy, fracture surface morphology and microstructures of punched holes were examined. It is revealed that the initial grain size has a noticeable effect on forming quality of holes punched by laser shock. The shape accuracy of punched holes degrades with the increase of grain size. As the laser power density is enhanced, the shape accuracy can be improved except for the case in which the ratio of foil thickness to initial grain size is approximately equal to 1. Compared with the fracture surface morphology in the quasistatic loading conditions, the fracture surface after laser shock can be divided into three zones including rollover, shearing and burr. The distribution of the above three zones strongly relates with the initial grain size. When the laser power density is enhanced, the shearing depth is not increased, but even diminishes in some cases. There is no obvious change of microstructures with the enhancement of laser power density. However, while the initial grain size is close to the foil thickness, single-crystal shear deformation may occur, suggesting that the ratio of foil thickness to initial grain size has an important impact on deformation behavior of metal foil in laser shock punching process.

Two-Level factorial screening of new plasmid/strain combinations for prodution of recombinant-DNA products.

PubMed

Emborg, C; Jepsen, P K; Biedermann, K

1989-05-01

This article treats the basic problem of selection of experimental conditions for microbiological experiments for evaluation of newly isolated bacterial strains, mutants, or plasmid/strain combinations. For this purpose shake flask experiments in a 2(10-4)confounded factorial design at resolution IV with four blocks of 16 flasks were used. The design was used for testing of two new strain/plasmid combinations (E. coli MT 102/403-SD2 and W 3110/403-SD2) i.e., both strains with the same plasmid 403-SD2. Both strains were integrated in the design, so both strains were tested with nine factors (temperature, aeration, glucose, initial pH, pH regulation, reduced aeration, chloramphenicol, acetate, and glycerol). With both strains the interaction between initial pH and reduced aeration had a significant influence on the yield of the recombinant-DNA product nuclease. There was more than a factor of 10 between lowest and highest yield of product. In this interactive system the strains reacted differently. MT 102/403-SD2 had highest yields at high initial pH (8.4) and no reduction in aeration, whereas W 3110/403-SD2 had highest yields of nuclease at low initial pH (7.4) and reduced aeration (rubber stopper inserted after cultivation for 12 h). These data (and previous work) clearly demonstrate that it is impossible to suggest a simple set of experimental conditions for testing of new plasmid/strain combinations. It is clear that the exclusive application of a standardized growth technique e.g., LB-medium at 37 degrees C at an unspecified and uncontrolled aeration level, may lead to wrong conclusions on properties and potentials of now plasmid/strain combinations and may lead to rejection of useful strains or plasmids.

The Lasting Influences of Early Food-Related Variety Experience: A Longitudinal Study of Vegetable Acceptance from 5 Months to 6 Years in Two Populations

PubMed Central

Maier-Nöth, Andrea; Schaal, Benoist; Leathwood, Peter; Issanchou, Sylvie

2016-01-01

Children’s vegetable consumption falls below current recommendations, highlighting the need to identify strategies that can successfully promote better acceptance of vegetables. Recently, experimental studies have reported promising interventions that increase acceptance of vegetables. The first, offering infants a high variety of vegetables at weaning, increased acceptance of new foods, including vegetables. The second, offering an initially disliked vegetable at 8 subsequent meals markedly increased acceptance for that vegetable. So far, these effects have been shown to persist for at least several weeks. We now present follow-up data at 15 months, 3 and 6 years obtained through questionnaire (15 mo, 3y) and experimental (6y) approaches. At 15 months, participants who had been breast-fed were reported as eating and liking more vegetables than those who had been formula-fed. The initially disliked vegetable that became accepted after repeated exposure was still liked and eaten by 79% of the children. At 3 years, the initially disliked vegetable was still liked and eaten by 73% of the children. At 6 years, observations in an experimental setting showed that children who had been breast-fed and children who had experienced high vegetable variety at the start of weaning ate more of new vegetables and liked them more. They were also more willing to taste vegetables than formula-fed children or the no or low variety groups. The initially disliked vegetable was still liked by 57% of children. This follow-up study suggests that experience with chemosensory variety in the context of breastfeeding or at the onset of complementary feeding can influence chemosensory preferences for vegetables into childhood. PMID:26968029

Parasite Removal, but Not Herbivory, Deters Future Parasite Attachment on Tomato

PubMed Central

Tjiurutue, Muvari Connie; Palmer-Young, Evan C.; Adler, Lynn S.

2016-01-01

Plants face many antagonistic interactions that occur sequentially. Often, plants employ defense strategies in response to the initial damage that are highly specific and can affect interactions with subsequent antagonists. In addition to herbivores and pathogens, plants face attacks by parasitic plants, but we know little about how prior herbivory compared to prior parasite attachment affects subsequent host interactions. If host plants can respond adaptively to these different damage types, we predict that prior parasitism would have a greater deterrent effect on subsequent parasites than would prior herbivory. To test the effects of prior parasitism and prior herbivory on subsequent parasitic dodder (Cuscuta spp.) preference, we conducted two separate greenhouse studies with tomato hosts (Solanum lycopersicum). In the first experiment, we tested the effects of previous dodder attachment on subsequent dodder preference on tomato hosts using three treatments: control plants that had no previous dodder attachment; dodder-removed plants that had an initial dodder seedling attached, removed and left in the same pot to simulate parasite death; and dodder-continuous plants with an initial dodder seedling that remained attached. In the second experiment, we tested the effects of previous caterpillar damage (Spodoptera exigua) and mechanical damage on future dodder attachment on tomato hosts. Dodder attached most slowly to tomato hosts that had dodder plants previously attached and then removed, compared to control plants or plants with continuous dodder attachment. In contrast, herbivory did not affect subsequent dodder attachment rate. These results indicate that dodder preference depended on the identity and the outcome of the initial attack, suggesting that early-season interactions have the potential for profound impacts on subsequent community dynamics. PMID:27529694

Upper-Tropospheric Synoptic-Scale Waves. Part II: Maintenance and Excitation of Quasi Modes.

NASA Astrophysics Data System (ADS)

Rivest, Chantal; Farrell, Brian F.

1992-11-01

In a preceding paper a simple dynamical model for the maintenance of upper-tropospheric waves was proposed: the upper-level Eady normal modes. In this paper it is shown that these modes have counterparts in basic states with positive tropospheric gradients of potential vorticity, and that these counterparts can be maintained and excited on time scales consistent with observations.In the presence of infinitesimal positive tropospheric gradients of potential vorticity, the upper-level normal-mode solutions no longer exist. That the normal-mode solution disappears when gradients are infinitesimal represents an apparent singularity and challenges the interpretation of upper-level synoptic-scale waves as related to the upper-level Eady normal modes. What happens to the upper-level modal solution in the presence of tropospheric gradients of potential vorticity is examined in a series of initial-value experiments. Our results show that they become slowly decaying quasi modes. Mathematically the quasi modes consist of a superposition of singular modes sharply peaked in the phase speed domain, and their decay proceeds as the modes interfere with one another. We repeat these experiments in basic states with a smooth tropopause in the presence of tropospheric and stratospheric gradients, and similar results are obtained.Following a previous study by Farrell, a class of near-optimal initial conditions for the excitation of upper-level waves is identified. The initial conditions consist of upper-tropospheric disturbances that lean against the shear. They strongly excite upper-level waves not only in the absence of tropospheric potential vorticity gradients, but also in their presence. This result is important mathematically since it suggests that quasi modes are as likely to emerge from favorably configured initial disturbances as true normal modes, although the excitation is followed by a slow decay.

UK end-of-life care services in dementia, initiatives and sustainability: results of a national online survey.

PubMed

Amador, Sarah; Goodman, Claire; Robinson, Louise; Sampson, Elizabeth L

2016-10-14

People living and dying with non-cancer diagnoses, including dementia, have poorer access to generalist and specialist palliative care than people with cancer, and experience worse outcomes in terms of pain and symptom control, and quality and experience of care. In the UK, the National Council for Palliative Care (NCPC) ran a national survey of services for end-of-life care for people with dementia (2008) in which 16 services were identified, and reported on case studies and examples of good practice. We updated the NCPC survey to review progress in previously identified services, identify factors that lead to sustainable services and identify new initiatives in this area of care. An online survey was developed and piloted before use. Initiatives were contacted via targeted (N=63) and open call invitations. The survey was made up of 5 sections. Quantitative data were analysed using descriptive statistics. 15 services responded. They engaged in a wide range of activities predominately providing direct care (80%) and workforce development/advisory or educational activities (87%). Results suggest that sustainability of services is reliant on clinicians with a leadership role and wider system support through funding mechanisms and a minimum level of integration within normal service provision. Recent initiatives are largely built on the expertise of the nursing profession (with or without input from medical consultants), and driven mainly by the charity and hospice sector. This has generated a potential new model of care provision in end of life dementia care, 'Hospice-enabled Dementia Care'. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Predicting mineral precipitation in fractures: The influence of local heterogeneity on the feedback between precipitation and permeability

NASA Astrophysics Data System (ADS)

Jones, T.; Detwiler, R. L.

2016-12-01

Long-term subsurface energy production and contaminant storage strategies often rely on induced-mineralization to control the transport of dissolved ions. In low-permeability rocks, precipitation is most likely to occur in fractures that act as leakage pathways for fluids that are in chemical disequilibrium with the formation minerals. These fractures are commonly idealized as parallel-plate channels with uniform surface mineralogy, and as a result, our predictions often suggest that precipitation leads to fast permeability reduction. However, natural fractures contain both heterogeneous mineralogy and three-dimensional surface roughness, and our understanding of how precipitation affects local permeability in these environments is limited. To examine the impacts of local heterogeneity on the feedback between mineral precipitation and permeability, we performed two long-term experiments in transparent analog fractures: (i) uniform-aperture and (ii) variable-aperture. We controlled the initial heterogeneous surface mineralogy in both experiments by seeding the bottom borosilicate fracture surfaces with randomly distributed clusters of CaCO3 crystals. Continuous flow ISCO pumps injected a well-mixed CaCl2-NaHCO3 solution, log(ΩCaCO3) = 1.44, into the fracture at 0.5 ml/min and transmitted-light techniques provided high-resolution (83 x 83 µm), direct measurements of aperture and fluid transport across the fracture. In experiment (i), precipitation decreased local aperture at discrete CaCO3 reaction sites near the fracture inlet, but transport variations across the fracture remained relatively small due to the initial lack of aperture heterogeneity. In contrast, the feedback between precipitation and aperture in experiment (ii) focused flow into large-aperture, preferential flow paths that contained significantly less CaCO3 area than the fracture scale average. Precipitation-induced aperture reduction in (ii) reduced dissolved ion transport into small-aperture regions of the fracture that were abundant with CaCO3 and led to a 72% decrease in measured precipitation rate. These results suggest that incorporating the effects of local heterogeneity may dramatically improve our ability to predict precipitation-induced permeability alterations in fractured rocks.

Dreaming of a Learning Task is Associated with Enhanced Sleep-Dependent Memory Consolidation

PubMed Central

Wamsley, Erin J.; Tucker, Matthew; Payne, Jessica D.; Benavides, Joseph; Stickgold, Robert

2010-01-01

Summary It is now well established that post-learning sleep is beneficial for human memory performance [1–5]. Meanwhile, human and animal studies demonstrate that learning-related neural activity is re-expressed during post-training non-rapid eye movement sleep (NREM) [6–9]. NREM sleep processes appear to be particularly beneficial for hippocampus-dependent forms of memory [1–3, 10]. These observations suggest that learning triggers the reactivation and reorganization of memory traces during sleep, a systems-level process that in turn enhances behavioral performance. Here, we hypothesized that dreaming about a learning experience during NREM sleep would be associated with improved performance on a hippocampus-dependent spatial memory task. Subjects (n=99) were trained on a virtual navigation task, and then retested on the same task 5 hours after initial training. Improved performance at retest was strongly associated with task-related dream imagery during an intervening afternoon nap. Task-related thoughts during wakefulness, in contrast, did not predict improved performance. These observations suggest that sleep-dependent memory consolidation in humans is facilitated by the offline reactivation of recently formed memories, and furthermore, that dream experiences reflect this memory processing. That similar effects were not seen during wakefulness suggests that these mnemonic processes are specific to the sleep state. PMID:20417102

Poloxamer 188 decreases susceptibility of artificial lipid membranes to electroporation.

PubMed Central

Sharma, V; Stebe, K; Murphy, J C; Tung, L

1996-01-01

The effect of a nontoxic, nonionic block co-polymeric surface active agent, poloxamer 188, on electroporation of artificial lipid membranes made of azolectin, was investigated. Two different experimental protocols were used in our study: charge pulse and voltage clamp. For the charge pulse protocol, membranes were pulsed with a 10-micronsecond rectangular voltage waveform, after which membrane voltage decay was observed through an external 1-M omega resistance. For the voltage clamp protocol the membranes were pulsed with a waveform that consisted of an initial 10-microsecond rectangular phase, followed by a negative sloped ramp that decayed to zero in the subsequent 500 microseconds. Several parameters characterizing the electroporation process were measured and compared for the control membranes and membranes treated with 1.0 mM poloxamer 188. For both the charge pulse and voltage clamp experiments, the threshold voltage (amplitude of initial rectangular phase) and latency time (time elapsed between the end of rectangular phase and the onset of membrane electroporation) were measured. Membrane conductance (measured 200 microseconds after the initial rectangular phase) and rise time (tr; the time required for the porated membrane to reach a certain conductance value) were also determined for the voltage clamp experiments, and postelectroporation time constant (PE tau; the time constant for transmembrane voltage decay after onset of electroporation) for the charge pulse experiments. The charge pulse experiments were performed on 23 membranes with 10 control and 13 poloxamer-treated membranes, and voltage pulse experiments on 49 membranes with 26 control and 23 poloxamer-treated membranes. For both charge pulse and voltage clamp experiments, poloxamer 188-treated membranes exhibited a statistically higher threshold voltage (p = 0.1 and p = 0.06, respectively), and longer latency time (p = 0.04 and p = 0.05, respectively). Also, poloxamer 188-treated membranes were found to have a relatively lower conductance (p = 0.001), longer time required for the porated membrane to reach a certain conductance value (p = 0.05), and longer postelectroporation time constant (p = 0.005). Furthermore, addition of poloxamer 188 was found to reduce the membrane capacitance by approximately 4-8% in 5 min. These findings suggest that poloxamer 188 adsorbs into the lipid bilayers, thereby decreasing their susceptibility to electroporation. Images FIGURE 1 PMID:8968593

Mathematical Simulation of the Process of Aerobic Treatment of Wastewater under Conditions of Diffusion and Mass Transfer Perturbations

NASA Astrophysics Data System (ADS)

Bomba, A. Ya.; Safonik, A. P.

2018-05-01

A mathematical model of the process of aerobic treatment of wastewater has been refined. It takes into account the interaction of bacteria, as well as of organic and biologically nonoxidizing substances under conditions of diffusion and mass transfer perturbations. An algorithm of the solution of the corresponding nonlinear perturbed problem of convection-diffusion-mass transfer type has been constructed, with a computer experiment carried out based on it. The influence of the concentration of oxygen and of activated sludge on the quality of treatment is shown. Within the framework of the model suggested, a possibility of automated control of the process of deposition of impurities in a biological filter depending on the initial parameters of the water medium is suggested.

Developing a Nuclear Grade of Alloy 617 for Gen IV Nuclear Energy Systems

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

Ren, Weiju; Swindeman, Robert W; Santella, Michael L

2010-01-01

Alloy 617, an attractive material not particularly developed for nuclear use, is now being considered as a leading candidate alloy by several countries for applications in the Gen IV Nuclear Energy Systems. An extensive review of its existing data suggests that it would be beneficial to refine the alloy s specification to a nuclear grade for the intended Gen IV systems. In this paper, rationale for developing a nuclear grade of the alloy is first discussed through an analysis on existing data from various countries. Then initial experiments for refining the alloy specification are described. Preliminary results have suggested themore » feasibility of the refinement approach, as well as the possibility for achieving a desirable nuclear grade. Based on the results, further research activities are recommended.« less

Mathematical Simulation of the Process of Aerobic Treatment of Wastewater under Conditions of Diffusion and Mass Transfer Perturbations

NASA Astrophysics Data System (ADS)

Bomba, A. Ya.; Safonik, A. P.

2018-03-01

A mathematical model of the process of aerobic treatment of wastewater has been refined. It takes into account the interaction of bacteria, as well as of organic and biologically nonoxidizing substances under conditions of diffusion and mass transfer perturbations. An algorithm of the solution of the corresponding nonlinear perturbed problem of convection-diffusion-mass transfer type has been constructed, with a computer experiment carried out based on it. The influence of the concentration of oxygen and of activated sludge on the quality of treatment is shown. Within the framework of the model suggested, a possibility of automated control of the process of deposition of impurities in a biological filter depending on the initial parameters of the water medium is suggested.

Observation learning versus physical practice leads to different consolidation outcomes in a movement timing task.

PubMed

Trempe, Maxime; Sabourin, Maxime; Rohbanfard, Hassan; Proteau, Luc

2011-03-01

Motor learning is a process that extends beyond training sessions. Specifically, physical practice triggers a series of physiological changes in the CNS that are regrouped under the term "consolidation" (Stickgold and Walker 2007). These changes can result in between-session improvement or performance stabilization (Walker 2005). In a series of three experiments, we tested whether consolidation also occurs following observation. In Experiment 1, participants observed an expert model perform a sequence of arm movements. Although we found evidence of observation learning, no significant difference was revealed between participants asked to reproduce the observed sequence either 5 min or 24 h later (no between-session improvement). In Experiment 2, two groups of participants observed an expert model perform two distinct movement sequences (A and B) either 10 min or 8 h apart; participants then physically performed both sequences after a 24-h break. Participants in the 8-h group performed Sequence B less accurately compared to participants in the 5-min group, suggesting that the memory representation of the first sequence had been stabilized and that it interfered with the learning of the second sequence. Finally, in Experiment 3, the initial observation phase was replaced by a physical practice phase. In contrast with the results of Experiment 2, participants in the 8-h group performed Sequence B significantly more accurately compared to participants in the 5-min group. Together, our results suggest that the memory representation of a skill learned through observation undergoes consolidation. However, consolidation of an observed motor skill leads to distinct behavioural outcomes in comparison with physical practice.

Contrasting response to nutrient manipulation in Arctic mesocosms are reproduced by a minimum microbial food web model.

PubMed

Larsen, Aud; Egge, Jorun K; Nejstgaard, Jens C; Di Capua, Iole; Thyrhaug, Runar; Bratbak, Gunnar; Thingstad, T Frede

2015-03-01

A minimum mathematical model of the marine pelagic microbial food web has previously shown to be able to reproduce central aspects of observed system response to different bottom-up manipulations in a mesocosm experiment Microbial Ecosystem Dynamics (MEDEA) in Danish waters. In this study, we apply this model to two mesocosm experiments (Polar Aquatic Microbial Ecology (PAME)-I and PAME-II) conducted at the Arctic location Kongsfjorden, Svalbard. The different responses of the microbial community to similar nutrient manipulation in the three mesocosm experiments may be described as diatom-dominated (MEDEA), bacteria-dominated (PAME-I), and flagellated-dominated (PAME-II). When allowing ciliates to be able to feed on small diatoms, the model describing the diatom-dominated MEDEA experiment give a bacteria-dominated response as observed in PAME I in which the diatom community comprised almost exclusively small-sized cells. Introducing a high initial mesozooplankton stock as observed in PAME-II, the model gives a flagellate-dominated response in accordance with the observed response also of this experiment. The ability of the model originally developed for temperate waters to reproduce population dynamics in a 10°C colder Arctic fjord, does not support the existence of important shifts in population balances over this temperature range. Rather, it suggests a quite resilient microbial food web when adapted to in situ temperature. The sensitivity of the model response to its mesozooplankton component suggests, however, that the seasonal vertical migration of Arctic copepods may be a strong forcing factor on Arctic microbial food webs.

Contrasting response to nutrient manipulation in Arctic mesocosms are reproduced by a minimum microbial food web model

PubMed Central

Larsen, Aud; Egge, Jorun K; Nejstgaard, Jens C; Di Capua, Iole; Thyrhaug, Runar; Bratbak, Gunnar; Thingstad, T Frede

2015-01-01

A minimum mathematical model of the marine pelagic microbial food web has previously shown to be able to reproduce central aspects of observed system response to different bottom-up manipulations in a mesocosm experiment Microbial Ecosystem Dynamics (MEDEA) in Danish waters. In this study, we apply this model to two mesocosm experiments (Polar Aquatic Microbial Ecology (PAME)-I and PAME-II) conducted at the Arctic location Kongsfjorden, Svalbard. The different responses of the microbial community to similar nutrient manipulation in the three mesocosm experiments may be described as diatom-dominated (MEDEA), bacteria-dominated (PAME-I), and flagellated-dominated (PAME-II). When allowing ciliates to be able to feed on small diatoms, the model describing the diatom-dominated MEDEA experiment give a bacteria-dominated response as observed in PAME I in which the diatom community comprised almost exclusively small-sized cells. Introducing a high initial mesozooplankton stock as observed in PAME-II, the model gives a flagellate-dominated response in accordance with the observed response also of this experiment. The ability of the model originally developed for temperate waters to reproduce population dynamics in a 10°C colder Arctic fjord, does not support the existence of important shifts in population balances over this temperature range. Rather, it suggests a quite resilient microbial food web when adapted to in situ temperature. The sensitivity of the model response to its mesozooplankton component suggests, however, that the seasonal vertical migration of Arctic copepods may be a strong forcing factor on Arctic microbial food webs. PMID:26074626

Importance of convective parameterization in ENSO predictions

NASA Astrophysics Data System (ADS)

Zhu, Jieshun; Kumar, Arun; Wang, Wanqiu; Hu, Zeng-Zhen; Huang, Bohua; Balmaseda, Magdalena A.

2017-06-01

This letter explored the influence of atmospheric convection scheme on El Niño-Southern Oscillation (ENSO) predictions using a set of hindcast experiments. Specifically, a low-resolution version of the Climate Forecast System version 2 is used for 12 month hindcasts starting from each April during 1982-2011. The hindcast experiments are repeated with three atmospheric convection schemes. All three hindcasts apply the identical initialization with ocean initial conditions taken from the European Centre for Medium-Range Weather Forecasts and atmosphere/land initial states from the National Centers for Environmental Prediction. Assessments indicate a substantial sensitivity of the sea surface temperature prediction skill to the different convection schemes, particularly over the eastern tropical Pacific. For the Niño 3.4 index, the anomaly correlation skill can differ by 0.1-0.2 at lead times longer than 2 months. Long-term simulations are further conducted with the three convection schemes to understand the differences in prediction skill. By conducting heat budget analyses for the mixed-layer temperature anomalies, it is suggested that the convection scheme having the highest skill simulates stronger and more realistic coupled feedbacks related to ENSO. Particularly, the strength of the Ekman pumping feedback is better represented, which is traced to more realistic simulation of surface wind stress. Our results imply that improving the mean state simulations in coupled (ocean-atmosphere) general circulation model (e.g., ameliorating the Intertropical Convergence Zone simulation) might further improve our ENSO prediction capability.

Non-Solenoidal Tokamak Startup via Inboard Local Helicity Injection on the Pegasus ST

NASA Astrophysics Data System (ADS)

Perry, J. M.; Barr, J. L.; Bodner, G. M.; Bongard, M. W.; Fonck, R. J.; Pachicano, J. L.; Reusch, J. A.; Rodriguez Sanchez, C.; Richner, N. J.; Schlossberg, D. J.

2016-10-01

Local helicity injection (LHI) is a non-solenoidal startup technique utilizing small injectors at the plasma edge to source current along helical magnetic field lines. Unstable injected current streams relax to a tokamak-like configuration with high toroidal current multiplication. Flexible placement of injectors permits tradeoffs between helicity injection rate, poloidal field induction, and magnetic geometry requirements for initial relaxation. Experiments using a new set of large-area injectors in the lower divertor explore the efficacy of high-field-side (HFS) injection. The increased area (4 cm2) current source is functional up to full Pegasus toroidal field (BT , inj = 0.23 T). However, relaxation to a tokamak state is increasingly frustrated for BT , inj > 0.15 T with uniform vacuum vertical field. Paths to relaxation at increased field include: manipulation of vacuum poloidal field geometry; increased injector current; and plasma initiation with outboard injectors, subsequently transitioning to divertor injector drive. During initial tests of HFS injectors, achieved Vinj was limited to 600 V by plasma-material interactions on the divertor plate, which may be mitigated by increasing injector elevation. In experiments with helicity injection as the dominant current drive Ip 0.13 MA has been attained, with T̲e > 100 eV and ne 1019 m-3. Extrapolation to full BT, longer pulse length, and Vinj 1 kV suggest Ip > 0.25 MA should be attainable in a plasma dominated by helicity drive. Work supported by US DOE Grant DE-FG02-96ER54375.

Shock, release and reshock of PBX 9502: experiments and modeling

NASA Astrophysics Data System (ADS)

Aslam, Tariq; Gustavsen, Richard; Whitworh, Nicholas; Menikoff, Ralph; Tarver, Craig; Handley, Caroline; Bartram, Brian

2017-06-01

We examine shock, release and reshock into the tri-amino-tri-nitro-benzene (TATB) based explosive PBX 9502 (95% TATB, 5% Kel-F 800) from both an experimental and modeling point of view. The experiments are performed on the 2-stage light gas gun at Los Alamos National Laboratory and are composed of a multi-layered impactor impinging on PBX 9502 backed by a polymethylmethacrylate window. The objective is to initially shock the PBX 9502 in the 7 GPa range (too weak to start significant reaction), then allow a rarefaction fan to release the material to a lower pressure/temperature state. Following this release, a strong second shock will recompress the PBX. If the rarefaction fan releases the PBX to a very low pressure, the ensuing second shock can increase the entropy and temperature substantially more than in previous double-shock experiments without an intermediate release. Predictions from a variety of reactive burn models (AWSD, CREST, Ignition and Growth, SURF) demonstrate significantly different behaviors and thus the experiments are an excellent validation test of the models, and may suggest improvements for subsequent modeling efforts.

Ion bombardment experiments suggesting an origin for organic particles in pre-cometary and cometary ices

NASA Technical Reports Server (NTRS)

Wdowiak, Thomas J.; Robinson, Edward L.; Flickinger, Gregory C.; Boyd, David A.

1989-01-01

During the Giotto and Vega encounters with Comet Halley both organic particles called CHON and energetic ions were detected. The acceleration of ions to hundreds of keV in the vicinity of the bow shock and near the nucleus may be a demonstration of a situation occurring in the early solar system (perhaps during the T Tauri stage) that led to the formation of organic particles only now released. Utilizing a Van de Graaff accelerator and a target chamber having cryogenic and mass spectrometer capabilities, frozen gases were bombarded at 10 K with 175 keV protons with the result that fluffy solid material remains after sublimation of the ice. Initial experiments were carried out with a gas mixture in parts of 170 carbon monoxide, 170 argon, 25 water, 20 nitrogen, and 15 methane formulated to reflect an interstellar composition in experiments involving the freezing out of the products of a plasma. The plasma experiments resulted in a varnish-like film residue that exhibited luminescence when excited with ultraviolet radiation, while the ion bombardment created particulate material that was not luminescent.

Longitudinal Investigation of Smoking Initiation and Relapse Among Younger and Older US Military Personnel

PubMed Central

Trone, Daniel W.; Peterson, Arthur V.; Jacobson, Isabel G.; Littman, Alyson J.; Maynard, Charles; Seelig, Amber D.; Crum-Cianflone, Nancy F.; Bricker, Jonathan B.

2015-01-01

Objectives. We examined whether military service, including deployment and combat experience, were related to smoking initiation and relapse. Methods. We included older (panel 1) and younger (panel 2) participants in the Millennium Cohort Study. Never smokers were followed for 3 to 6 years for smoking initiation, and former smokers were followed for relapse. Complementary log-log regression models estimated the relative risk (RR) of initiation and relapse by military exposure while adjusting for demographic, health, and lifestyle factors. Results. Deployment with combat experience predicted higher initiation rate (panel 1: RR = 1.44; 95% confidence interval [CI] = 1.28, 1.62; panel 2: RR = 1.26; 95% CI = 1.04, 1.54) and relapse rate (panel 1 only: RR = 1.48; 95% CI = 1.36, 1.62). Depending on the panel, previous mental health disorders, life stressors, and other military and nonmilitary characteristics independently predicted initiation and relapse. Conclusions. Deployment with combat experience and previous mental disorder may identify military service members in need of intervention to prevent smoking initiation and relapse. PMID:25880953

Erosion of volcanic ocean islands: insights from modeling, topographic analyses, and cosmogenic exposure dating

NASA Astrophysics Data System (ADS)

Huppert, K.; Perron, J. T.; Ferrier, K.; Mukhopadhyay, S.; Rosener, M.; Douglas, M.

2016-12-01

With homogeneous bedrock, dramatic rainfall gradients, paleoshorelines, and datable remnant topography, volcanic ocean islands provide an exceptional natural experiment in landscape evolution. Analyses traversing gradients in island climate and bedrock age have the potential to advance our understanding of landscape evolution in a diverse range of continental settings. However, as small, conical, dominantly subsiding, and initially highly permeable landmasses, islands are unique, and it remains unclear how these properties influence their erosional history. We use a landscape evolution model and observations from the Hawaiian island of Kaua'i and other islands to characterize the topographic evolution of volcanic ocean islands. We present new measurements of helium-3 concentrations in detrital olivine from 20 rivers on Kaua'i. These measurements indicate that minimum erosion rates over the past 3 to 48 kyr are on average 2.6 times faster than erosion rates averaged over the past 3.9 to 4.4 Myr estimated from the volume of river canyons. This apparent acceleration of erosion rates on Kaua'i is consistent with observations on other islands; erosion rates estimated from the volume of river canyons on 31 islands worldwide, combined with observations of minimal incision on young island volcanoes, suggest a progressive increase in erosion rates over the first few million years of island landscape development. Using a landscape evolution model, we perform a set of experiments to quantify the contribution of subsidence, climate change, and initial geometry to changes in island erosion rates through time. We base these experiments on the evolution of Kaua'i, and we use measured erosion rates and the observed topography to calibrate the model. We find that progressive steepening of island topography by canyon incision drives an acceleration of erosion rates over time. Increases in mean channel and hillslope gradient with island age in the global compilation suggest this may be a general trend in the topographic evolution of volcanic ocean islands.

Photoperiod as a proximate factor in control of seasonality in the subtropical male Tree Sparrow, Passer montanus

PubMed Central

2011-01-01

Background Most species of birds exhibit well-defined seasonality in their various physiological and behavioral functions like reproduction, molt, bill color etc. such that they occur at the most appropriate time of the year. Day length has been shown to be a major source of temporal information regulating seasonal reproduction and associated events in a number of avian species. The present study aims to investigate the role of photoperiod in control of seasonal cycles in the subtropical male tree sparrow (Passer montanus) and to compare its responses at Shillong (Latitude 25°34'N, Longitude 91°53'E) with those exhibited by its conspecifics and related species at other latitudes. Results Initial experiment involving study of seasonal cycles revealed that the wild tree sparrows posses definite seasonal cycles of testicular volume, molt and bill color. These cycles were found remarkably linked to annual solar cycle suggesting the possibility of their photoperiodic control. To confirm this possibility in the next experiment, the photosensitive birds were exposed to three different light-dark regimes that were close to what they experience at this latitude: 9L/15D (close to shortest day length), 12L/12D (equinox day length) and 14L/10D (close to longest day length) for 18 months. Tree sparrows showed testicular growth followed by regression and development of photorefractoriness, molting and bill color changes only under long daily photoperiods (12 L and 14 L) but not under short daily photoperiod (9 L). Birds, under stimulatory photoperiods, did not show reinitiation of the above responses after the completion of initiation regression cycle even after their exposure to these photoperiods for 18 months. This precludes the possibility of circannual rhythm generation and suggests the involvement of photoperiodic mechanism in control of their seasonal cycles. Further, replacement of body and primary feathers progressed with gonadal regression only under long days suggesting that the two high energy demanding events of reproduction and molt are phased at two different times in the annual cycle of the bird and are photoperiodically regulated. Results of the final experiment involving exposure of photosensitive birds to a variety of photoperiodic treatments (9L/15D, 10L/14D, 11L/13D, 12L/12D, 14L/10D and 16L/8D) for 30 days suggested that the light falling for 11 h or more is important in inducing testicular growth and function in this species. Conclusion These results clearly indicate that despite of small photofluctuation, subtropical tree sparrows are capable of fine discrimination of photoperiodic information and use day length as a proximate environmental factor to time their seasonal responses similar to their conspecifics and related species at other latitudes suggesting the conservation of photoperiodic control mechanism in them. PMID:21223557

Comparison of the two cerebral hemispheres in inhibitory processes operative during movement preparation

PubMed Central

Klein, Pierre-Alexandre; Duque, Julie; Labruna, Ludovica; Ivry, Richard B.

2015-01-01

Neuroimaging and neuropsychological studies suggest that in right-handed individuals, the left hemisphere plays a dominant role in praxis, relative to the right hemisphere. However hemispheric asymmetries assessed with transcranial magnetic stimulation (TMS) has not shown consistent differences in corticospinal (CS) excitability of the two hemispheres during movements. In the current study, we systematically explored hemispheric asymmetries in inhibitory processes that are manifest during movement preparation and initiation. Single-pulse TMS was applied over the left or right primary motor cortex (M1LEFT and M1RIGHT, respectively) to elicit motor-evoked potentials (MEPs) in the contralateral hand while participants performed a two-choice reaction time task requiring a cued movement of the left or right index finger. In Experiments 1 and 2, TMS probes were obtained during a delay period following the presentation of the preparatory cue that provided partial or full information about the required response. MEPs were suppressed relative to baseline regardless of whether they were elicited in a cued or uncued hand. Importantly, the magnitude of these inhibitory changes in CS excitability was similar when TMS was applied over M1LEFT or M1RIGHT, irrespective of the amount of information carried by the preparatory cue. In Experiment 3, there was no preparatory cue and TMS was applied at various time points after the imperative signal. When CS excitability was probed in the cued effector, MEPs were initially inhibited and then rose across the reaction time interval. This function was similar for M1LEFT and M1RIGHT TMS. When CS excitability was probed in the uncued effector, MEPs remained inhibited throughout the RT interval. However, MEPs in right FDI became more inhibited during selection and initiation of a left hand movement, whereas MEPs in left FDI remained relatively invariant across RT interval for the right hand. In addition to these task-specific effects, there was a global difference in CS excitability across experiments between the two hemispheres. When the intensity of stimulation was set to 115% of the resting threshold, MEPs were larger when the TMS probe was applied over the M1LEFT than over M1RIGHT. In summary, while the latter result suggests that M1LEFT is more excitable than M1RIGHT, the recruitment of preparatory inhibitory mechanisms is similar within the two cerebral hemispheres. PMID:26458519