Kinetics of the addition of olefins to Si-centered radicals: the critical role of dispersion interactions revealed by theory and experiment.

PubMed

Johnson, Erin R; Clarkin, Owen J; Dale, Stephen G; DiLabio, Gino A

2015-06-04

Solution-phase rate constants for the addition of selected olefins to the triethylsilyl and tris(trimethylsilyl)silyl radicals are measured using laser-flash photolysis and competition kinetics. The results are compared with predictions from density functional theory (DFT) calculations, both with and without dispersion corrections obtained from the exchange-hole dipole moment (XDM) model. Without a dispersion correction, the rate constants are consistently underestimated; the errors increase with system size, up to 10(6) s(-1) for the largest system considered. Dispersion interactions preferentially stabilize the transition states relative to the separated reactants and bring the DFT-calculated rate constants into excellent agreement with experiment. Thus, dispersion interactions are found to play a key role in determining the kinetics for addition reactions, particularly those involving sterically bulky functional groups.

Distinct subsystems for the parafoveal processing of spatial and linguistic information during eye fixations in reading.

PubMed

Inhoff, Albrecht W; Radach, Ralph; Eiter, Brianna M; Juhasz, Barbara

2003-07-01

Two experiments examined readers' use of parafoveally obtained word length information for word recognition. Both experiments manipulated the length (number of constituent characters) of a parafoveally previewed target word so that it was either accurately or inaccurately specified. In Experiment 1, previews also either revealed or denied useful orthographic information. In Experiment 2, parafoveal targets were either high- or low-frequency words. Eye movement contingent display changes were used to show the intact target upon its fixation. Examination of target viewing duration showed completely additive effects of word length previews and of ortho-graphic previews in Experiment 1, viewing duration being shorter in the accurate-length and the orthographic preview conditions. Experiment 2 showed completely additive effects of word length and word frequency, target viewing being shorter in the accurate-length and the high-frequency conditions. Together these results indicate that functionally distinct subsystems control the use of parafoveally visible spatial and linguistic information in reading. Parafoveally visible spatial information appears to be used for two distinct extralinguistic computations: visual object selection and saccade specification.

Atomic-Scale Visualization of Quasiparticle Interference on a Type-II Weyl Semimetal Surface.

PubMed

Zheng, Hao; Bian, Guang; Chang, Guoqing; Lu, Hong; Xu, Su-Yang; Wang, Guangqiang; Chang, Tay-Rong; Zhang, Songtian; Belopolski, Ilya; Alidoust, Nasser; Sanchez, Daniel S; Song, Fengqi; Jeng, Horng-Tay; Yao, Nan; Bansil, Arun; Jia, Shuang; Lin, Hsin; Hasan, M Zahid

2016-12-23

We combine quasiparticle interference simulation (theory) and atomic resolution scanning tunneling spectromicroscopy (experiment) to visualize the interference patterns on a type-II Weyl semimetal Mo_{x}W_{1-x}Te_{2} for the first time. Our simulation based on first-principles band topology theoretically reveals the surface electron scattering behavior. We identify the topological Fermi arc states and reveal the scattering properties of the surface states in Mo_{0.66}W_{0.34}Te_{2}. In addition, our result reveals an experimental signature of the topology via the interconnectivity of bulk and surface states, which is essential for understanding the unusual nature of this material.

Additional Layers of Violence: The Intersections of Gender and Disability in the Violence Experiences of Women With Physical Disabilities in South Africa.

PubMed

van der Heijden, Ingrid; Abrahams, Naeemah; Harries, Jane

2016-04-27

South Africa has unprecedented levels of violence and many South African women are exposed to violence during their lifetime. This article explores how gender and disability intersect in women's experiences of violence during their lifetime. Repeat in-depth qualitative interviews with 30 physically disabled women in Cape Town reveal that women with physical disabilities are exposed to various forms of violence, and shows how their impairments shape their violence experiences. The most common forms of violence women with disabilities experience are psychological violence, financial abuse, neglect, and deprivation, with disability stigma playing a central role and contributing to how women with disabilities are exploited and dehumanized. Constructions of women as asexual shape their sexual relationships and experiences of sexual violence. This article identifies that women with disabilities are more at risk and experience additional layers of violence than women without disabilities. These additional risks and layers of violence need to be recognized and inform interventions to prevent and respond to violence against women with disabilities in the country. Prevention of violence against women with physical disabilities in South Africa needs to address the role of disability stigma that shapes the types of violence they experience, change gender norms, and create accessible and safe environments and economic empowerment opportunities. © The Author(s) 2016.

"Sentido de Pertenencia": A Hierarchical Analysis Predicting Sense of Belonging among Latino College Students

ERIC Educational Resources Information Center

Strayhorn, Terrell Lamont

2008-01-01

The present study estimated the influence of academic and social collegiate experiences on Latino students' sense of belonging, controlling for background differences, using hierarchical analysis techniques with a nested design. In addition, results were compared between Latino students and their White counterparts. Findings reveal that grades,…

Effect of kernel characteristics on color and flavor development during peanut roasting: two years of data

USDA-ARS?s Scientific Manuscript database

Experiments with Crop Year (CY) 2014 samples from the Uniform Peanut Performance Trials (UPPT) revealed that color and flavor profile development were related to kernel moisture content (MC) during dry roasting. That work was repeated with CY 2015 UPPT samples with additional replication. Raw MC, ...

Developments in Young Infants' Reasoning about Occluded Objects

ERIC Educational Resources Information Center

Aguiar, Andrea; Baillargeon, Renee

2002-01-01

Eight experiments were conducted to examine 3- and 3.5-month-old infants' responses to occlusion events. The results revealed two developments, one in infants' knowledge of when objects should and should not be occluded and the other in infants' ability to posit additional objects to make sense of events that would otherwise violate their…

What a speaker's choice of frame reveals: reference points, frame selection, and framing effects.

PubMed

McKenzie, Craig R M; Nelson, Jonathan D

2003-09-01

Framing effects are well established: Listeners' preferences depend on how outcomes are described to them, or framed. Less well understood is what determines how speakers choose frames. Two experiments revealed that reference points systematically influenced speakers' choices between logically equivalent frames. For example, speakers tended to describe a 4-ounce cup filled to the 2-ounce line as half full if it was previously empty but described it as half empty if it was previously full. Similar results were found when speakers could describe the outcome of a medical treatment in terms of either mortality or survival (e.g., 25% die vs. 75% survive). Two additional experiments showed that listeners made accurate inferences about speakers' reference points on the basis of the selected frame (e.g., if a speaker described a cup as half empty, listeners inferred that the cup used to be full). Taken together, the data suggest that frames reliably convey implicit information in addition to their explicit content, which helps explain why framing effects are so robust.

Long-term nitrogen addition affects the phylogenetic turnover of soil microbial community responding to moisture pulse

DOE PAGES

Liu, Chi; Yao, Minjie; Stegen, James C.; ...

2017-12-13

How press disturbance (long-term) influences the phylogenetic turnover of soil microbial communities responding to pulse disturbances (short-term) is not fully known. Understanding the complex connections between the history of environmental conditions, assembly processes and microbial community dynamics is necessary to predict microbial response to perturbation. Here, we started by investigating phylogenetic spatial turnover (based on DNA) of soil prokaryotic communities after long-term nitrogen (N) deposition and temporal turnover (based on RNA) of communities responding to pulse by conducting short-term rewetting experiments. The results showed that moderate N addition increased ecological stochasticity and phylogenetic diversity. In contrast, high N addition slightlymore » increased homogeneous selection and decreased phylogenetic diversity. Examining the system with higher phylogenetic resolution revealed a moderate contribution of variable selection across the whole N gradient. The moisture pulse experiment showed that high N soils had higher rates of phylogenetic turnover across short phylogenetic distances and significant changes in community compositions through time. Long-term N input history influenced spatial turnover of microbial communities, but the dominant community assembly mechanisms differed across different N deposition gradients. We further revealed an interaction between press and pulse disturbances whereby deterministic processes were particularly important following pulse disturbances in high N soils.« less

Long-term nitrogen addition affects the phylogenetic turnover of soil microbial community responding to moisture pulse

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

Liu, Chi; Yao, Minjie; Stegen, James C.

How press disturbance (long-term) influences the phylogenetic turnover of soil microbial communities responding to pulse disturbances (short-term) is not fully known. Understanding the complex connections between the history of environmental conditions, assembly processes and microbial community dynamics is necessary to predict microbial response to perturbation. Here, we started by investigating phylogenetic spatial turnover (based on DNA) of soil prokaryotic communities after long-term nitrogen (N) deposition and temporal turnover (based on RNA) of communities responding to pulse by conducting short-term rewetting experiments. The results showed that moderate N addition increased ecological stochasticity and phylogenetic diversity. In contrast, high N addition slightlymore » increased homogeneous selection and decreased phylogenetic diversity. Examining the system with higher phylogenetic resolution revealed a moderate contribution of variable selection across the whole N gradient. The moisture pulse experiment showed that high N soils had higher rates of phylogenetic turnover across short phylogenetic distances and significant changes in community compositions through time. Long-term N input history influenced spatial turnover of microbial communities, but the dominant community assembly mechanisms differed across different N deposition gradients. We further revealed an interaction between press and pulse disturbances whereby deterministic processes were particularly important following pulse disturbances in high N soils.« less

Long-term nitrogen addition affects the phylogenetic turnover of soil microbial community responding to moisture pulse.

PubMed

Liu, Chi; Yao, Minjie; Stegen, James C; Rui, Junpeng; Li, Jiabao; Li, Xiangzhen

2017-12-13

How press disturbance (long-term) influences the phylogenetic turnover of soil microbial communities responding to pulse disturbances (short-term) is not fully known. Understanding the complex connections between the history of environmental conditions, assembly processes and microbial community dynamics is necessary to predict microbial response to perturbation. We started by investigating phylogenetic spatial turnover (based on DNA) of soil prokaryotic communities after long-term nitrogen (N) deposition and temporal turnover (based on RNA) of communities responding to pulse by conducting short-term rewetting experiments. The results showed that moderate N addition increased ecological stochasticity and phylogenetic diversity. In contrast, high N addition slightly increased homogeneous selection and decreased phylogenetic diversity. Examining the system with higher phylogenetic resolution revealed a moderate contribution of variable selection across the whole N gradient. The moisture pulse experiment showed that high N soils had higher rates of phylogenetic turnover across short phylogenetic distances and significant changes in community compositions through time. Long-term N input history influenced spatial turnover of microbial communities, but the dominant community assembly mechanisms differed across different N deposition gradients. We further revealed an interaction between press and pulse disturbances whereby deterministic processes were particularly important following pulse disturbances in high N soils.

Magnetic x-ray scattering studies of holmium using synchro- tron radiation

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

Gibbs, D.; Moncton, D.E.; D'Amico, K.L.

1985-07-08

We present the results of magnetic x-ray scattering experiments on the rare-earth metal holmium using synchrotron radiation. Direct high-resolution measurements of the nominally incommensurate magnetic satellite reflections reveal new lock-in behavior which we explain within a simple spin-discommensuration model. As a result of magnetoelastic coupling, the spin-discommensuration array produces additional x-ray diffraction satellites. Their observation further substantiates the model and demonstrates additional advantages of synchrotron radiation for magnetic-structure studies.

Experience with proactive interference diminishes its effects: mechanisms of change.

PubMed

Wahlheim, Christopher N; Jacoby, Larry L

2011-02-01

In three experiments, we examined the mechanisms by which prior experience with proactive interference (PI) diminished its effects. Cued recall tasks conforming to an A-B, A-D paradigm were used to induce PI effects. Experiment 1 showed that reduced PI was not due to a reduction in attention to the source of PI. Experiment 2 revealed that participants' awareness of PI effects on memory performance increased with experience, resulting in a shift in encoding processes. Experiment 3 demonstrated that changes in encoding provided additional support for recollection that further enhanced participants' ability to constrain their retrieval processing to the appropriate source of information at the time of test. These results can be interpreted as showing that experience with PI enhances awareness of its effects and allows individuals to adjust their learning and retrieval strategies to compensate for such effects.

Three-year-olds obey the sample size principle of induction: the influence of evidence presentation and sample size disparity on young children's generalizations.

PubMed

Lawson, Chris A

2014-07-01

Three experiments with 81 3-year-olds (M=3.62years) examined the conditions that enable young children to use the sample size principle (SSP) of induction-the inductive rule that facilitates generalizations from large rather than small samples of evidence. In Experiment 1, children exhibited the SSP when exemplars were presented sequentially but not when exemplars were presented simultaneously. Results from Experiment 3 suggest that the advantage of sequential presentation is not due to the additional time to process the available input from the two samples but instead may be linked to better memory for specific individuals in the large sample. In addition, findings from Experiments 1 and 2 suggest that adherence to the SSP is mediated by the disparity between presented samples. Overall, these results reveal that the SSP appears early in development and is guided by basic cognitive processes triggered during the acquisition of input. Copyright © 2013 Elsevier Inc. All rights reserved.

Differentiating the Sources of Taiwanese High School Students' Multidimensional Science Learning Self-Efficacy: An Examination of Gender Differences

NASA Astrophysics Data System (ADS)

Lin, Tzung-Jin; Tsai, Chin-Chung

2017-04-01

The main purpose of this study was to investigate Taiwanese high school students' multi-dimensional self-efficacy and its sources in the domain of science. Two instruments, Sources of Science Learning Self-Efficacy (SSLSE) and Science Learning Self-Efficacy (SLSE), were used. By means of correlation and regression analyses, the relationships between students' science learning self-efficacy and the sources of their science learning self-efficacy were examined. The findings revealed that the four sources of the students' self-efficacy were found to play significant roles in their science learning self-efficacy. By and large, Mastery Experience and Vicarious Experience were found to be the two salient influencing sources. Several gender differences were also revealed. For example, the female students regarded Social Persuasion as the most influential source in the "Science Communication" dimension, while the male students considered Vicarious Experience as the main efficacy source. Physiological and Affective States, in particular, was a crucial antecedent of the female students' various SLSE dimensions, including "Conceptual Understanding," "Higher-Order Cognitive Skills," and "Science Communication." In addition, the variations between male and female students' responses to both instruments were also unraveled. The results suggest that, first, the male students perceived themselves as having more mastery experience, vicarious experience and social persuasion than their female counterparts. Meanwhile, the female students experienced more negative emotional arousal than the male students. Additionally, the male students were more self-efficacious than the females in the five SLSE dimensions of "Conceptual Understanding," "Higher-Order Cognitive Skills," "Practical Work," "Everyday Application," and "Science Communication."

Differentiating the Sources of Taiwanese High School Students' Multidimensional Science Learning Self-Efficacy: An Examination of Gender Differences

NASA Astrophysics Data System (ADS)

Lin, Tzung-Jin; Tsai, Chin-Chung

2018-06-01

The main purpose of this study was to investigate Taiwanese high school students' multi-dimensional self-efficacy and its sources in the domain of science. Two instruments, Sources of Science Learning Self-Efficacy (SSLSE) and Science Learning Self-Efficacy (SLSE), were used. By means of correlation and regression analyses, the relationships between students' science learning self-efficacy and the sources of their science learning self-efficacy were examined. The findings revealed that the four sources of the students' self-efficacy were found to play significant roles in their science learning self-efficacy. By and large, Mastery Experience and Vicarious Experience were found to be the two salient influencing sources. Several gender differences were also revealed. For example, the female students regarded Social Persuasion as the most influential source in the "Science Communication" dimension, while the male students considered Vicarious Experience as the main efficacy source. Physiological and Affective States, in particular, was a crucial antecedent of the female students' various SLSE dimensions, including "Conceptual Understanding," "Higher-Order Cognitive Skills," and "Science Communication." In addition, the variations between male and female students' responses to both instruments were also unraveled. The results suggest that, first, the male students perceived themselves as having more mastery experience, vicarious experience and social persuasion than their female counterparts. Meanwhile, the female students experienced more negative emotional arousal than the male students. Additionally, the male students were more self-efficacious than the females in the five SLSE dimensions of "Conceptual Understanding," "Higher-Order Cognitive Skills," "Practical Work," "Everyday Application," and "Science Communication."

Evidence for task conflict in the Stroop effect.

PubMed

Goldfarb, Liat; Henik, Avishai

2007-10-01

C. M. MacLeod and P. A. MacDonald (2000) suggested that congruent and incongruent Stroop stimuli cause more task conflict than neutral stimuli because the anterior cingulate cortex is more activated with these stimuli. This study investigated behavioral expression for this pattern. Experiment 1 reduced task conflict control by increasing the proportion of nonword neutrals. Additionally, half the trials had conflict or neutral cues. The control reduction revealed the task conflict. For noncued trials, response time was longer for congruent stimuli than for neutral stimuli (reverse facilitation effect). In addition, response time for congruent stimuli was longer when stimuli were uncued vs. cued. Experiment 2 increased task conflict control by changing the neutral stimuli to noncolor words. Consequently, the task conflict expression disappeared. (c) 2007 APA

International Linear Collider Reference Design Report

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

Brau, James,; Okada, Yasuhiro,; Walker, Nicholas J.,

2007-08-13

{lg_bullet} What is the universe? How did it begin? {lg_bullet} What are matter and energy? What are space and time? These basic questions have been the subject of scientific theories and experiments throughout human history. The answers have revolutionized the enlightened view of the world, transforming society and advancing civilization. Universal laws and principles govern everyday phenomena, some of them manifesting themselves only at scales of time and distance far beyond everyday experience. Particle physics experiments using particle accelerators transform matter and energy, to reveal the basic workings of the universe. Other experiments exploit naturally occurring particles, such as solarmore » neutrinos or cosmic rays, and astrophysical observations, to provide additional insights.« less

Free classification of regional dialects of American English.

PubMed

Clopper, Cynthia G; Pisoni, David B

2007-07-01

Recent studies have found that naïve listeners perform poorly in forced-choice dialect categorization tasks. However, the listeners' error patterns in these tasks reveal systematic confusions between phonologically similar dialects. In the present study, a free classification procedure was used to measure the perceptual similarity structure of regional dialect variation in the United States. In two experiments, participants listened to a set of short English sentences produced by male talkers only (Experiment 1) and by male and female talkers (Experiment 2). The listeners were instructed to group the talkers by regional dialect into as many groups as they wanted with as many talkers in each group as they wished. Multidimensional scaling analyses of the data revealed three primary dimensions of perceptual similarity (linguistic markedness, geography, and gender). In addition, a comparison of the results obtained from the free classification task to previous results using the same stimulus materials in six-alternative forced-choice categorization tasks revealed that response biases in the six-alternative task were reduced or eliminated in the free classification task. Thus, the results obtained with the free classification task in the current study provided further evidence that the underlying structure of perceptual dialect category representations reflects important linguistic and sociolinguistic factors.

Participatory health system priority setting: Evidence from a budget experiment.

PubMed

Costa-Font, Joan; Forns, Joan Rovira; Sato, Azusa

2015-12-01

Budget experiments can provide additional guidance to health system reform requiring the identification of a subset of programs and services that accrue the highest social value to 'communities'. Such experiments simulate a realistic budget resource allocation assessment among competitive programs, and position citizens as decision makers responsible for making 'collective sacrifices'. This paper explores the use of a participatory budget experiment (with 88 participants clustered in social groups) to model public health care reform, drawing from a set of realistic scenarios for potential health care users. We measure preferences by employing a contingent ranking alongside a budget allocation exercise (termed 'willingness to assign') before and after program cost information is revealed. Evidence suggests that the budget experiment method tested is cognitively feasible and incentive compatible. The main downside is the existence of ex-ante "cost estimation" bias. Additionally, we find that participants appeared to underestimate the net social gain of redistributive programs. Relative social value estimates can serve as a guide to aid priority setting at a health system level. Copyright © 2015 Elsevier Ltd. All rights reserved.

The Influence of Task-Irrelevant Music on Language Processing: Syntactic and Semantic Structures

PubMed Central

Hoch, Lisianne; Poulin-Charronnat, Benedicte; Tillmann, Barbara

2011-01-01

Recent research has suggested that music and language processing share neural resources, leading to new hypotheses about interference in the simultaneous processing of these two structures. The present study investigated the effect of a musical chord's tonal function on syntactic processing (Experiment 1) and semantic processing (Experiment 2) using a cross-modal paradigm and controlling for acoustic differences. Participants read sentences and performed a lexical decision task on the last word, which was, syntactically or semantically, expected or unexpected. The simultaneously presented (task-irrelevant) musical sequences ended on either an expected tonic or a less-expected subdominant chord. Experiment 1 revealed interactive effects between music-syntactic and linguistic-syntactic processing. Experiment 2 showed only main effects of both music-syntactic and linguistic-semantic expectations. An additional analysis over the two experiments revealed that linguistic violations interacted with musical violations, though not differently as a function of the type of linguistic violations. The present findings were discussed in light of currently available data on the processing of music as well as of syntax and semantics in language, leading to the hypothesis that resources might be shared for structural integration processes and sequencing. PMID:21713122

Perception of biomechanical motions by infants: implementation of various processing constraints.

PubMed

Bertenthal, B I; Proffitt, D R; Kramer, S J

1987-11-01

Geometry informs us that there exist a large number of possible connectivity patterns consistent with a point-light display of a person walking. Yet there is only one pattern consistent with a "stick figure" representation of the human form, and that pattern is uniquely specified by those pairwise connections that remain locally rigid. In this study, sensitivity to local rigidity in biomechanical displays was investigated in 3- and 5-month-old infants. The results of Experiment 1 revealed that by 5 months of age, infants discriminate a locally rigid point-light walker display from one in which local rigidity is perturbed. In Experiment 2 we tested infants' sensitivity to the same stimuli when those stimuli were inverted. Contrary to the preceding experiment, the results revealed no evidence of discrimination. Taken together, these findings suggest that infants are sensitive to local rigidity in biomechanical displays but that this sensitivity is orientation specific. Possible mechanisms for this specificity are discussed in the context of additional constraints on the processing of biomechanical displays.

Undergraduates' perceptions of the value of practical inhalation sedation experience in a UK dental school.

PubMed

Walley, S; Albadri, S

2015-10-01

This was to establish the level and reported value of paediatric IHS experience from the perspective of final year undergraduates and to evaluate whether those students with more experience expressed feeling better-prepared for future practice and more likely to undertake further postgraduate education in IHS. All final year students were invited to complete an anonymous questionnaire designed to elicit undergraduate perceptions of IHS using visual analogue scales and free-text questions. A response rate of 77 % was achieved. Results revealed that only 21 % of participants reported acting as operator sedationist in ten or more IHS cases. Thus, the majority of undergraduates' did not meet the recommended quantity of practical IHS experiences, as outlined by the British Dental Sedation Teachers Group. In general, students felt on the value of IHS in the management of anxious children and expressed a desire to undertake further postgraduate education in conscious sedation. However, those students with more experience of practical IHS expressed feeling better able to describe the IHS experience with patients and parents, and were more satisfied with the quality of teaching. Furthermore free-text comments revealed that, regardless of experience, students wished to gain more experience of the practical administration of IHS. There is a need to increase the provision of IHS training within an undergraduate curriculum, in addition to improving the accessibility of postgraduate sedation courses.

Yeast pheromone pathway modeling using Petri nets

PubMed Central

2014-01-01

Background Our environment is composed of biological components of varying magnitude. The relationships between the different biological elements can be represented as a biological network. The process of mating in S. cerevisiae is initiated by secretion of pheromone by one of the cells. Our interest lies in one particular question: how does a cell dynamically adapt the pathway to continue mating under severe environmental changes or under mutation (which might result in the loss of functionality of some proteins known to participate in the pheromone pathway). Our work attempts to answer this question. To achieve this, we first propose a model to simulate the pheromone pathway using Petri nets. Petri nets are directed graphs that can be used for describing and modeling systems characterized as concurrent, asynchronous, distributed, parallel, non-deterministic, and/or stochastic. We then analyze our Petri net-based model of the pathway to investigate the following: 1) Given the model of the pheromone response pathway, under what conditions does the cell respond positively, i.e., mate? 2) What kinds of perturbations in the cell would result in changing a negative response to a positive one? Method In our model, we classify proteins into two categories: core component proteins (set ψ) and additional proteins (set λ). We randomly generate our model's parameters in repeated simulations. To simulate the pathway, we carry out three different experiments. In the experiments, we simply change the concentration of the additional proteins (λ) available to the cell. The concentration of proteins in ψ is varied consistently from 300 to 400. In Experiment 1, the range of values for λ is set to be 100 to 150. In Experiment 2, it is set to be 151 to 200. In Experiment 3, the set λ is further split into σ and ς, with the idea that proteins in σ are more important than those in ς. The range of values for σ is set to be between 151 to 200 while that of ς is 100 to 150. Decision trees were derived from each of the first two experiments to allow us to more easily analyze the conditions under which the pheromone is expressed. Conclusion The simulation results reveal that a cell can overcome the detrimental effects of the conditions by using more concentration of additional proteins in λ. The first two experiments provide evidence that employing more concentration of proteins might be one of the ways that the cell uses to adapt itself in inhibiting conditions to facilitate mating. The results of the third experiment reveal that in some case the protein set σ is sufficient in regulating the response of the cell. Results of Experiments 4 and 5 reveal that there are certain conditions (parameters) in the model that are more important in determining whether a cell will respond positively or not. PMID:25080237

Yeast pheromone pathway modeling using Petri nets.

PubMed

Majumdar, Abhishek; Scott, Stephen D; Deogun, Jitender S; Harris, Steven

2014-01-01

Our environment is composed of biological components of varying magnitude. The relationships between the different biological elements can be represented as a biological network. The process of mating in S. cerevisiae is initiated by secretion of pheromone by one of the cells. Our interest lies in one particular question: how does a cell dynamically adapt the pathway to continue mating under severe environmental changes or under mutation (which might result in the loss of functionality of some proteins known to participate in the pheromone pathway). Our work attempts to answer this question. To achieve this, we first propose a model to simulate the pheromone pathway using Petri nets. Petri nets are directed graphs that can be used for describing and modeling systems characterized as concurrent, asynchronous, distributed, parallel, non-deterministic, and/or stochastic. We then analyze our Petri net-based model of the pathway to investigate the following: 1) Given the model of the pheromone response pathway, under what conditions does the cell respond positively, i.e., mate? 2) What kinds of perturbations in the cell would result in changing a negative response to a positive one? In our model, we classify proteins into two categories: core component proteins (set ψ) and additional proteins (set λ). We randomly generate our model's parameters in repeated simulations. To simulate the pathway, we carry out three different experiments. In the experiments, we simply change the concentration of the additional proteins (λ) available to the cell. The concentration of proteins in ψ is varied consistently from 300 to 400. In Experiment 1, the range of values for λ is set to be 100 to 150. In Experiment 2, it is set to be 151 to 200. In Experiment 3, the set λ is further split into σ and ς, with the idea that proteins in σ are more important than those in ς. The range of values for σ is set to be between 151 to 200 while that of ς is 100 to 150. Decision trees were derived from each of the first two experiments to allow us to more easily analyze the conditions under which the pheromone is expressed. The simulation results reveal that a cell can overcome the detrimental effects of the conditions by using more concentration of additional proteins in λ. The first two experiments provide evidence that employing more concentration of proteins might be one of the ways that the cell uses to adapt itself in inhibiting conditions to facilitate mating. The results of the third experiment reveal that in some case the protein set σ is sufficient in regulating the response of the cell. Results of Experiments 4 and 5 reveal that there are certain conditions (parameters) in the model that are more important in determining whether a cell will respond positively or not.

Two-dimensional homogeneous isotropic fluid turbulence with polymer additives

NASA Astrophysics Data System (ADS)

Gupta, Anupam; Perlekar, Prasad; Pandit, Rahul

2015-03-01

We carry out an extensive and high-resolution direct numerical simulation of homogeneous, isotropic turbulence in two-dimensional fluid films with air-drag-induced friction and with polymer additives. Our study reveals that the polymers (a) reduce the total fluid energy, enstrophy, and palinstrophy; (b) modify the fluid energy spectrum in both inverse- and forward-cascade régimes; (c) reduce small-scale intermittency; (d) suppress regions of high vorticity and strain rate; and (e) stretch in strain-dominated regions. We compare our results with earlier experimental studies and propose new experiments.

Halogenation of Hydraulic Fracturing Additives in the Shale Well Parameter Space

NASA Astrophysics Data System (ADS)

Sumner, A. J.; Plata, D.

2017-12-01

Horizontal Drilling and Hydraulic fracturing (HDHF) involves the deep-well injection of a `fracking fluid' composed of diverse and numerous chemical additives designed to facilitate the release and collection of natural gas from shale plays. The potential impacts of HDHF operations on water resources and ecosystems are numerous, and analyses of flowback samples revealed organic compounds from both geogenic and anthropogenic sources. Furthermore, halogenated chemicals were also detected, and these compounds are rarely disclosed, suggesting the in situ halogenation of reactive additives. To test this transformation hypothesis, we designed and operated a novel high pressure and temperature reactor system to simulate the shale well parameter space and investigate the chemical reactivity of twelve commonly disclosed and functionally diverse HDHF additives. Early results revealed an unanticipated halogenation pathway of α-β unsaturated aldehyde, Cinnamaldehyde, in the presence of oxidant and concentrated brine. Ongoing experiments over a range of parameters informed a proposed mechanism, demonstrating the role of various shale-well specific parameters in enabling the demonstrated halogenation pathway. Ultimately, these results will inform a host of potentially unintended interactions of HDHF additives during the extreme conditions down-bore of a shale well during HDHF activities.

Dissemination of a Multidrug-Resistant VIM-1- and CMY-99-Producing Proteus mirabilis Clone in Bulgaria.

PubMed

Markovska, Rumyana; Schneider, Ines; Keuleyan, Emma; Ivanova, Dobrinka; Lesseva, Magdalena; Stoeva, Temenuga; Sredkova, Mariya; Bauernfeind, Adolf; Mitov, Ivan

2017-04-01

The aim of this study was to analyze the beta-lactamases and the molecular epidemiology of 19 clinically significant isolates of Proteus mirabilis with decreased susceptibility to imipenem, which have been collected from seven hospitals, located in different Bulgarian towns (Sofia, Varna, and Pleven). The isolates were obtained from blood, urine, tracheal and wound specimens. One additional isolate from hospital environment was included. Susceptibility testing, conjugation experiments, and plasmid replicon typing were carried out. Beta-lactamases were characterized by isoelectric focusing, PCR, and sequencing. Clonal relatedness was investigated by RAPD and PFGE. Integron mapping was performed by PCR and sequencing. All isolates showed a multidrug-resistance profile, but remained susceptible to piperacillin/tazobactam, cefepime, meropenem, and fosfomycin. They produced identical beta-lactamases, namely: TEM-1, VIM-1, and CMY-99. PCR mapping revealed that the bla VIM-1 gene was part of a class 1 integron that additionally included the aac(6')-I, dhfrA1, and ant(3″)-Ia genes. In addition, 17 of the isolates carried the armA gene. Conjugation experiments and plasmid replicon typing were unsuccessful. The isolates were clonally related according to RAPD and PFGE typing. This study reveals the nationwide distribution of a multidrug-resistant P. mirabilis clone producing VIM-1 and CMY-99 along with the presence of different aminoglycoside resistance mechanisms.

Homocysteine remethylation in broilers fed surfeit choline or betaine and varying levels and sources of methionine from eight to twenty-two days of age.

PubMed

Pillai, P B; Fanatico, A C; Blair, M E; Emmert, J L

2006-10-01

Experiments were conducted to assess the effect of surfeit choline (CHOL) or betaine (BET) on growth performance and homocysteine (HCY) remethylation of young broilers fed graded levels of DL-Met (DLM) or 2-hydroxy-4-(methylthio) butanoic acid (HMB). In Experiment 1, a corn-peanut meal diet deficient in Met (0.25% digestible) and Cys (0.28% digestible) was fed; treatments were formulated to contain graded levels (0, 0.04, or 0.08%) of Met from DLM or 0.04% HMB (adjusted for 88% purity) that were fed in the presence or absence of surfeit isomethyl CHOL (0.25%) or BET (0.28%). In Experiment 2, identical treatments were used, but an additional level of HMB (0.08%) was fed, and the basal diet was adequate in Cys (0.43% digestible). There was no overall effect of CHOL or BET on growth performance in Experiments 1 and 2 (P > 0.05); a significant improvement (P < 0.05) in weight gain and feed efficiency did occur with CHOL and BET addition to the basal diet in Experiment 2. In both experiments, weight gain increased linearly (P < 0.05) with the addition of DLM or HMB. Slope ratio methodology was used to assess HMB efficacy in Experiment 2. In the presence of adequate Cys, HMB efficacy was 81.3%; addition of surfeit BET or CHOL had minimal effect on efficacy. The stable isotope study revealed that CHOL and BET addition to diets deficient in Met and Cys or Met alone increased HCY remethylation. It also showed that CHOL and BET have greater influence on folate-dependent remethylation of HCY (via Met synthase) than on BET-dependent remethylation (via BET-HCY methyltransferase) and that levels of CHOL and BET and type of S amino acid deficiency effect remethylation and HMB efficacy.

Random laser action in bovine semen

NASA Astrophysics Data System (ADS)

Smuk, Andrei; Lazaro, Edgar; Olson, Leif P.; Lawandy, N. M.

2011-03-01

Experiments using bovine semen reveal that the addition of a high-gain water soluble dye results in random laser action when excited by a Q-switched, frequency doubled, Nd:Yag laser. The data shows that the linewidth collapse of the emission is correlated to the sperm count of the individual samples, potentially making this a rapid, low sample volume approach to count determination.

Personality of Wild Male Crested Macaques (Macaca nigra)

PubMed Central

Neumann, Christof; Agil, Muhammad; Widdig, Anja; Engelhardt, Antje

2013-01-01

Animal personalities, i.e. consistent differences in behavior across time and/or context, have received increased attention of behavioral biologists over the last years. Recent research shows that personalities represent traits on which natural and sexual selection work and which can have substantial fitness consequences. The aim of this study is to establish the personality structure of crested macaque (Macaca nigra) males as foundation for future studies on its adaptive value. We collected behavioral data through focal animal sampling and additionally conducted two sets of playback experiments. Results of a factor analysis on the behavioral data revealed a four factor structure with components we labeled Anxiety, Sociability, Connectedness and Aggressiveness. Results from the experiments revealed an additional and independent Boldness factor but the absence of Neophilia. Overall, this structure resembles other macaque and animal species with the exception of Connectedness, which might be a consequence of the species' tolerant social style. Our results thus not only form the basis for future studies on the adaptive value of personality in crested macaques but also contribute an important data point for investigating the evolution of personality structure from a comparative perspective by refining, for example, which personality factors characterized the last common ancestor of hominids and macaques. PMID:23940517

Adverse childhood experiences and sexual victimization in adulthood.

PubMed

Ports, Katie A; Ford, Derek C; Merrick, Melissa T

2016-01-01

Understanding the link between adverse childhood experiences (ACEs) and sexual victimization (SV) in adulthood may provide important information about the level of risk for adult SV and sexual re-victimization among childhood sexual abuse (CSA) survivors. In the present paper, we explore the relationship between ACEs, including CSA, and SV in adulthood. Data from the CDC-Kaiser ACE Study were used to examine the effect of experiences of early adversity on adult SV. Adult HMO members (n=7,272) undergoing a routine health exam provided detailed information about ACEs that occurred at age 18 or younger and their experiences of SV in adulthood. Analyses revealed that as ACE score increased, so did risk of experiencing SV in adulthood. Each of the ACE variables was significantly associated with adult SV, with CSA being the strongest predictor of adult SV. In addition, for those who reported CSA, there was a cumulative increase in adult SV risk with each additional ACE experienced. As such, early adversity is a risk factor for adult SV. In particular, CSA is a significant risk factor for sexual re-victimization in adulthood, and additional early adversities experienced by CSA survivors may heighten adult SV risk above and beyond the risk associated with CSA alone. Given the interconnectedness among various experiences of early adversity, adult SV prevention actions must consider how other violence-related and non-violence-related traumatic experiences may exacerbate the risk conferred by CSA on subsequent victimization. Published by Elsevier Ltd.

The influences of ammonia on aerosol formation in the ozonolysis of styrene: roles of Criegee intermediate reactions

PubMed Central

Ma, Qiao; Lin, Xiaoxiao; Yang, Chengqiang; Long, Bo; Zhang, Weijun

2018-01-01

The influences of ammonia (NH3) on secondary organic aerosol (SOA) formation from ozonolysis of styrene have been investigated using chamber experiments and quantum chemical calculations. With the value of [O3]0/[styrene]0 ratios between 2 and 4, chamber experiments were carried out without NH3 or under different [NH3]/[styrene]0 ratios. The chamber experiments reveal that the addition of NH3 led to significant decrease of SOA yield. The overall SOA yield decreased with the [NH3]0/[styrene]0 increasing. In addition, the addition of NH3 at the beginning of the reaction or several hours after the reaction occurs had obviously different influence on the yield of SOA. Gas phase reactions of Criegee intermediates (CIs) with aldehydes and NH3 were studied in detail by theoretical methods to probe into the mechanisms behind these phenomena. The calculated results showed that 3,5-diphenyl-1,2,4-trioxolane, a secondary ozonide formed through the reactions of C6H5ĊHOO· with C6H5CHO, could make important contribution to the aerosol composition. The addition of excess NH3 may compete with aldehydes, decreasing the secondary ozonide yield to some extent and thus affect the SOA formation. PMID:29892406

High hunger state increases olfactory sensitivity to neutral but not food odors.

PubMed

Stafford, Lorenzo D; Welbeck, Kimberley

2011-01-01

Understanding how hunger state relates to olfactory sensitivity has become more urgent due to their possible role in obesity. In 2 studies (within-subjects: n = 24, between-subjects: n = 40), participants were provided with lunch before (satiated state) or after (nonsatiated state) testing and completed a standardized olfactory threshold test to a neutral odor (Experiments 1 and 2) and discrimination test to a food odor (Experiment 2). Experiment 1 revealed that olfactory sensitivity was greater in the nonsatiated versus satiated state, with additionally increased sensitivity for the low body mass index (BMI) compared with high BMI group. Experiment 2 replicated this effect for neutral odors, but in the case of food odors, those in a satiated state had greater acuity. Additionally, whereas the high BMI group had higher acuity to food odors in the satiated versus nonsatiated state, no such differences were found for the low BMI group. The research here is the first to demonstrate how olfactory acuity changes as a function of hunger state and relatedness of odor to food and that BMI can predict differences in olfactory sensitivity.

Free classification of regional dialects of American English

PubMed Central

Clopper, Cynthia G.; Pisoni, David B.

2011-01-01

Recent studies have found that naïve listeners perform poorly in forced-choice dialect categorization tasks. However, the listeners' error patterns in these tasks reveal systematic confusions between phonologically similar dialects. In the present study, a free classification procedure was used to measure the perceptual similarity structure of regional dialect variation in the United States. In two experiments, participants listened to a set of short English sentences produced by male talkers only (Experiment 1) and by male and female talkers (Experiment 2). The listeners were instructed to group the talkers by regional dialect into as many groups as they wanted with as many talkers in each group as they wished. Multidimensional scaling analyses of the data revealed three primary dimensions of perceptual similarity (linguistic markedness, geography, and gender). In addition, a comparison of the results obtained from the free classification task to previous results using the same stimulus materials in six-alternative forced-choice categorization tasks revealed that response biases in the six-alternative task were reduced or eliminated in the free classification task. Thus, the results obtained with the free classification task in the current study provided further evidence that the underlying structure of perceptual dialect category representations reflects important linguistic and sociolinguistic factors. PMID:21423862

Focusing on task conflict in the Stroop effect.

PubMed

Entel, Olga; Tzelgov, Joseph

2018-03-01

Two types of conflict underlie performance in the Stroop task-informational (between the incongruent word and its ink color) and task (between the relevant color-naming task and the irrelevant word-reading task). We manipulated congruent-to-neutral trial ratio in an attempt to reveal whether task conflict can be monitored and controlled in the absence of an informational conflict. In our first experiment, no incongruent trials were included, thus allowing examination of a pure task conflict situation. The results revealed an impressively large facilitation when most of the stimuli were congruent and a smaller yet significant facilitation when most of the stimuli were neutrals. In Experiments 2, exposing participants to incongruent trials during pre-experimental practice (but not during the experimental blocks) slowed down the responses to congruent trials, resulting in a reduced facilitation effect in the mostly congruent condition, and in a negative facilitation in the mostly neutral condition. In our third experiment, we replicated our results, eliminating possible contingency and frequency biases. Overall, our findings show that experiencing, or at least expecting, informational conflict is essential to reveal conflict, while control is recruited through task demands. This challenges previous findings and points out that additional research is needed to clarify the necessity of informational conflict for conflict detection.

Using semantic memory to boost 'episodic' recall in a case of developmental amnesia.

PubMed

Brandt, Karen R; Gardiner, John M; Vargha-Khadem, Faraneh; Baddeley, Alan D; Mishkin, Mortimer

2006-07-17

We report two experiments that investigated factors that might boost 'episodic' recall for Jon, a developmental amnesic whose episodic memory is gravely impaired but whose semantic memory seems relatively normal. Experiment 1 showed that Jon's recall improved following a semantic study task compared with a non-semantic study task, as well as following four repeated study trials compared with only one. Experiment 2 additionally revealed that Jon's recall improved after acting compared with reading action phrases at study, but only if the phrases were well integrated semantically. The results provide some support for the hypothesis that Jon's 'episodic' recall depends on the extent to which he is able to retrieve events using semantic memory.

Revisiting an open access monograph experiment: measuring citations and tweets 5 years later.

PubMed

Snijder, Ronald

An experiment run in 2009 could not assess whether making monographs available in open access enhanced scholarly impact. This paper revisits the experiment, drawing on additional citation data and tweets. It attempts to answer the following research question: does open access have a positive influence on the number of citations and tweets a monograph receives, taking into account the influence of scholarly field and language? The correlation between monograph citations and tweets is also investigated. The number of citations and tweets measured in 2014 reveal a slight open access advantage, but the influence of language or subject should also be taken into account. However, Twitter usage and citation behaviour hardly overlap.

Effect of vermicompost on growth, yield and nutrition status of tomato (Lycopersicum esculentum).

PubMed

Azarmi, Rasool; Ziveh, Parviz Sharifi; Satari, Mohammad Reza

2008-07-15

An experiment was conducted to determine the effects of vermicompost on growth, yield and fruit quality of tomato (Lycopersicum esculentum var. Super Beta) in a field condition. The experiment was a randomized complete block design with four replications. The different rates of vermicompost (0, 5, 10 and 15 t ha(-1)) was incorporated into the top 15 cm of soil. During experiment period, fruits were harvested twice in a week and total yield were recorded for two months. At the end of experiment, growth characteristics such as leaf number, leaf area and shoot dry weights were determined. The results revealed that addition of vermicompost at rate of 15 t ha(-1) significantly (at p < 0.05) increased growth and yield compared to control. Vermicompost with rate of 15 t ha(-1) increased EC of fruit juice and percentage of fruit dry matter up to 30 and 24%, respectively. The content of K, P, Fe and Zn in the plant tissue increased 55, 73, 32 and 36% compared to untreated plots respectively. The result of our experiment showed addition of vermicompost had significant (p < 0.05) positive effects on growth, yield and elemental content of plant as compared to control.

Lake Granbury and Lake Whitney Assessment Initiative Final Scientific/Technical Report Summary

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

Harris, B. L.; Roelke, Daniel; Brooks, Bryan

A team of Texas AgriLife Research, Baylor University and University of Texas at Arlington researchers studied the biology and ecology of Prymnesium parvum (golden algae) in Texas lakes using a three-fold approach that involved system-wide monitoring, experimentation at the microcosm and mesocosm scales, and mathematical modeling. The following are conclusions, to date, regarding this organism's ecology and potential strategies for mitigation of blooms by this organism. In-lake monitoring revealed that golden algae are present throughout the year, even in lakes where blooms do not occur. Compilation of our field monitoring data with data collected by Texas Parks and Wildlife andmore » Brazos River Authority (a period spanning a decade) revealed that inflow and salinity variables affect bloom formations. Thresholds for algae populations vary per lake, likely due to adaptations to local conditions, and also to variations in lake-basin morphometry, especially the presence of coves that may serve as hydraulic storage zones for P. parvum populations. More specifically, our in-lake monitoring showed that the highly toxic bloom that occurred in Lake Granbury in the winter of 2006/2007 was eliminated by increased river inflow events. The bloom was flushed from the system. The lower salinities that resulted contributed to golden algae not blooming in the following years. However, flushing is not an absolute requirement for bloom termination. Laboratory experiments have shown that growth of golden algae can occur at salinities ~1-2 psu but only when temperatures are also low. This helps to explain why blooms are possible during winter months in Texas lakes. Our in-lake experiments in Lake Whitney and Lake Waco, as well as our laboratory experiments, revealed that cyanobacteria, or some other bacteria capable of producing algicides, were able to prevent golden algae from blooming. Identification of this organism is a high priority as it may be a key to managing golden algae blooms. Our numerical modeling results support the idea that cyanobacteria, through allelopathy, control the timing of golden algae blooms in Lake Granbury. The in-lake experiments in Lake Whitney and Lake Waco also revealed that as golden algae blooms develop, there are natural enemies (a species of rotifer, and a virus) that help slow the population growth. Again, better characterization of these organisms is a high priority as it may be key to managing golden algae blooms. Our laboratory and in-lake experiments and field monitoring have shown that nutrient additions will remove toxicity and prevent golden algae from blooming. In fact, other algae displace the golden algae after nutrient additions. Additions of ammonia are particularly effective, even at low doses (much lower than what is employed in fish hatchery ponds). Application of ammonia in limited areas of lakes, such as in coves, should be explored as a management option. The laboratory experiments and field monitoring also show that the potency of toxins produced by P. parvum is greatly reduced when water pH is lower, closer to neutral levels. Application of mild acid to limited areas of lakes (but not to a level where acidic conditions are created), such as in coves, should be explored as a management option. Finally, our field monitoring and mathematical modeling revealed that flushing/dilution at high enough levels could prevent P. parvum from forming blooms and/or terminate existing blooms. This technique could work using deeper waters within a lake to flush the surface waters of limited areas of the same lakes, such as in coves and should be explored as a management option. In this way, water releases from upstream reservoirs would not be necessary and there would be no addition of nutrients in the lake.« less

Manipulating Protein-Protein Interactions in Nonribosomal Peptide Synthetase Type II Peptidyl Carrier Proteins.

PubMed

Jaremko, Matt J; Lee, D John; Patel, Ashay; Winslow, Victoria; Opella, Stanley J; McCammon, J Andrew; Burkart, Michael D

2017-10-10

In an effort to elucidate and engineer interactions in type II nonribosomal peptide synthetases, we analyzed biomolecular recognition between the essential peptidyl carrier proteins and adenylation domains using nuclear magnetic resonance (NMR) spectroscopy, molecular dynamics, and mutational studies. Three peptidyl carrier proteins, PigG, PltL, and RedO, in addition to their cognate adenylation domains, PigI, PltF, and RedM, were investigated for their cross-species activity. Of the three peptidyl carrier proteins, only PigG showed substantial cross-pathway activity. Characterization of the novel NMR solution structure of holo-PigG and molecular dynamics simulations of holo-PltL and holo-PigG revealed differences in structures and dynamics of these carrier proteins. NMR titration experiments revealed perturbations of the chemical shifts of the loop 1 residues of these peptidyl carrier proteins upon their interaction with the adenylation domain. These experiments revealed a key region for the protein-protein interaction. Mutational studies supported the role of loop 1 in molecular recognition, as mutations to this region of the peptidyl carrier proteins significantly modulated their activities.

Protein NMR Studies of Substrate Binding to Human Blood Group A and B Glycosyltransferases.

PubMed

Grimm, Lena Lisbeth; Weissbach, Sophie; Flügge, Friedemann; Begemann, Nora; Palcic, Monica M; Peters, Thomas

2017-07-04

Donor and acceptor substrate binding to human blood group A and B glycosyltransferases (GTA, GTB) has been studied by a variety of protein NMR experiments. Prior crystallographic studies had shown these enzymes to adopt an open conformation in the absence of substrates. Binding either of the donor substrate UDP-Gal or of UDP induces a semiclosed conformation. In the presence of both donor and acceptor substrates, the enzymes shift towards a closed conformation with ordering of an internal loop and the C-terminal residues, which then completely cover the donor-binding pocket. Chemical-shift titrations of uniformly 2 H, 15 N-labeled GTA or GTB with UDP affected about 20 % of all crosspeaks in 1 H, 15 N TROSY-HSQC spectra, reflecting substantial plasticity of the enzymes. On the other hand, it is this conformational flexibility that impedes NH backbone assignments. Chemical-shift-perturbation experiments with δ1-[ 13 C]methyl-Ile-labeled samples revealed two Ile residues-Ile123 at the bottom of the UDP binding pocket, and Ile192 as part of the internal loop-that were significantly disturbed upon stepwise addition of UDP and H-disaccharide, also revealing long-range perturbations. Finally, methyl TROSY-based relaxation dispersion experiments do not reveal micro- to millisecond timescale motions. Although this study reveals substantial conformational plasticity of GTA and GTB, the matter of how binding of substrates shifts the enzymes into catalytically competent states remains enigmatic. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Stimulation of waste decomposition in an old landfill by air injection.

PubMed

Wu, Chuanfu; Shimaoka, Takayuki; Nakayama, Hirofumi; Komiya, Teppei; Chai, Xiaoli

2016-12-01

Three pilot-scale lysimeters were operated for 4.5years to quantify the change in the carbon and nitrogen pool in an old landfill under various air injection conditions. The results indicate that air injection at the bottom layer facilitated homogeneous distribution of oxygen in the waste matrix. Substantial total organic carbon (TOC) decomposition and methane generation reduction were achieved. Considerable amount of nitrogen was removed, suggesting that in situ nitrogen removal via the effective simultaneous nitrification and denitrification mechanism is viable. Moreover, material mass change measurements revealed a slight mass reduction of aged MSW (by approximately 4.0%) after 4.5years of aeration. Additionally, experiments revealed that intensive aeration during the final stage of the experiment did not further stimulate the degradation of the aged MSW. Therefore, elimination of the labile fraction of aged MSW should be considered the objective of in situ aeration. Copyright © 2016 Elsevier Ltd. All rights reserved.

A study of deoxyribonucleotide metabolism and its relation to DNA synthesis. Supercomputer simulation and model-system analysis.

PubMed

Heinmets, F; Leary, R H

1991-06-01

A model system (1) was established to analyze purine and pyrimidine metabolism. This system has been expanded to include macrosimulation of DNA synthesis and the study of its regulation by terminal deoxynucleoside triphosphates (dNTPs) via a complex set of interactions. Computer experiments reveal that our model exhibits adequate and reasonable sensitivity in terms of dNTP pool levels and rates of DNA synthesis when inputs to the system are varied. These simulation experiments reveal that in order to achieve maximum DNA synthesis (in terms of purine metabolism), a proper balance is required in guanine and adenine input into this metabolic system. Excessive inputs will become inhibitory to DNA synthesis. In addition, studies are carried out on rates of DNA synthesis when various parameters are changed quantitatively. The current system is formulated by 110 differential equations.

Perceptions of Taiwanese nursing students' English-language progression following interactive scenario development and role play.

PubMed

Robinson, Carolyn I; Harvey, Theresa M; Tseng 曾翊瑄, Monica

2016-10-01

The English language has been recognised as an international language, enabling the globalisation of education and work opportunities. An institute in Taiwan has committed to strengthening English teaching by implementing a student-centred teaching and learning activity using role play. In addition, the involvement of a visiting teacher from Australia has been established. Data collection consisted of a questionnaire that collected qualitative and quantitative data that revealed student perceptions and attitudes towards learning English including nursing terminology, teamwork and communication. Fifty five of sixty students participating in the activity completed the questionnaire. Students regarded this as a positive experience for learning English, collegiality and teamwork. This project revealed that students who are not generally exposed to English-speaking people enjoyed this experience. They gained confidence in their ability to learn English in a collegial atmosphere where teamwork and supportive relationships were developed, despite the perception that learning English was difficult.

Peer support for carers: a qualitative investigation of the experiences of carers and peer volunteers.

PubMed

Greenwood, Nan; Habibi, Ruth; Mackenzie, Ann; Drennan, Vari; Easton, Nicky

2013-09-01

Being a carer of someone with dementia can be rewarding and also challenging. Volunteer peer support schemes for carers are being introduced, little is known about either their impact on carers and volunteers or about volunteers' and carers' experiences. This study investigated peer volunteer and carer recipient experiences of a peer support service. Thematic analysis of 13 in-depth interviews with 9 carers and 4 peer volunteers revealed that peer support helped both carers and peer volunteers through the realization that they were "not alone" in their experiences and emotions. Additional carer benefits included opportunities to talk freely about difficult experiences and learning how others cope. Volunteers found their role rewarding, describing satisfaction from putting their own experiences to good use. These findings highlight the isolation and exclusion experienced by current and former carers of people with dementia and draw attention to the benefits of peer support for both the groups.

Removing but not adding elements of a context affects generalization of instrumental responses.

PubMed

Bernal-Gamboa, Rodolfo; Nieto, Javier; Uengoer, Metin

2018-01-05

Three experiments with rats investigated whether adding or removing elements of a context affects generalization of instrumental behavior. Each of the experiments used a free operant procedure. In Experiments 1 and 2, rats were trained to press a lever for food in a distinctive context. Then, transfer of lever pressing was tested in a context created either by adding an element to the context of initial acquisition or by removing one of the acquisition context's elements. In Experiment 3, a similar generalization test was conducted after rats received acquisition and extinction within the same context. For Experiments 1 and 2, we observed that removing elements from the acquisition context disrupted acquisition performance, whereas the addition of elements to the context did not. Experiment 3 revealed that removing elements from but not adding elements to the original context improved extinction performance. Our results are consistent with an elemental view of context representation.

Daily School Peer Victimization Experiences Among Mexican-American Adolescents: Associations with Psychosocial, Physical and School Adjustment

PubMed Central

Gonzales, Nancy A.; Fuligni, Andrew J.

2014-01-01

School bullying incidents, particularly experiences with victimization, are a significant social and health concern among adolescents. The current study extended past research by examining the daily peer victimization experiences of Mexican-American adolescents and examining how chronic (mean-level) and episodic (daily-level) victimization incidents at school are associated with psychosocial, physical and school adjustment. Across a two-week span, 428 ninth and tenth grade Mexican-American students (51 % female) completed brief checklists every night before going to bed. Hierarchical linear model analyses revealed that, at the individual level, Mexican-American adolescents’ who reported more chronic peer victimization incidents across the two-weeks also reported heightened distress and academic problems. After accounting for adolescent’s mean levels of peer victimization, daily victimization incidents were associated with more school adjustment problems (i.e., academic problems, perceived role fulfillment as a good student). Additionally, support was found for the mediation model in which distress accounts for the mean-level association between peer victimization and academic problems. The results from the current study revealed that everyday peer victimization experiences among Mexican-American high school students have negative implications for adolescents’ adjustment, across multiple domains. PMID:23238764

"Will I ever be a true woman?" An exploration of the experiences of women with vestibulodynia.

PubMed

Groven, Karen Synne; Råheim, Målfrid; Håkonsen, Elin; Haugstad, Gro Killi

2016-08-01

In this study we explored the experiences of Norwegian women living with vestibulodynia, a chronic disease affecting young women all over the world. Using a phenomenological approach we conducted in-depth interviews with eight women who had struggled with vestibulodynia for several years. Our findings reveal that their efforts to fulfill their partners' sexual desires as well as their own represented an encompassing ongoing process. In addition, we highlight the interrelationship between the intensity of vulvar pain experienced by individual women and decisions women make about prioritizing their own sexual needs.

Cryptic biodiversity effects: importance of functional redundancy revealed through addition of food web complexity.

PubMed

Philpott, Stacy M; Pardee, Gabriella L; Gonthier, David J

2012-05-01

Interactions between predators and the degree of functional redundancy among multiple predator species may determine whether herbivores experience increased or decreased predation risk. Specialist parasites can modify predator behavior, yet rarely have cascading effects on multiple predator species and prey been evaluated. We examined influences of specialist phorid parasites (Pseudacteon spp.) on three predatory ant species and herbivores in a coffee agroecosystem. Specifically, we examined whether changes in ant richness affected fruit damage by the coffee berry borer (Hypothenemus hampei) and whether phorids altered multi-predator effects. Each ant species reduced borer damage, and without phorids, increasing predator richness did not further decrease borer damage. However, with phorids, activity of one ant species was reduced, indicating that the presence of multiple ant species was necessary to limit borer damage. In addition, phorid presence revealed synergistic effects of multiple ant species, not observed without the presence of this parasite. Thus, a trait-mediated cascade resulting from a parasite-induced predator behavioral change revealed the importance of functional redundancy, predator diversity, and food web complexity for control of this important pest.

Using Colaizzi's method of data analysis to explore the experiences of nurse academics teaching on satellite campuses.

PubMed

Wirihana, Lisa; Welch, Anthony; Williamson, Moira; Christensen, Martin; Bakon, Shannon; Craft, Judy

2018-03-16

Phenomenology is a useful methodological approach in qualitative nursing research. It enables researchers to put aside their perceptions of a phenomenon and give meaning to a participant's experiences. Exploring the experiences of others enables previously unavailable insights to be discovered. To delineate the implementation of Colaizzi's ( 1978 ) method of data analysis in descriptive phenomenological nursing research. The use of Colaizzi's method of data analysis enabled new knowledge to be revealed and provided insights into the experiences of nurse academics teaching on satellite campuses. Local adaptation of the nursing curriculum and additional unnoticed responsibilities had not been identified previously and warrant further research. Colaizzi's ( 1978 ) method of data analysis is rigorous and robust, and therefore a qualitative method that ensures the credibility and reliability of its results. It allows researchers to reveal emergent themes and their interwoven relationships. Researchers using a descriptive phenomenological approach should consider using this method as a clear and logical process through which the fundamental structure of an experience can be explored. Colaizzi's phenomenological methodology can be used reliably to understand people's experiences. This may prove beneficial in the development of therapeutic policy and the provision of patient-centred care. ©2018 RCN Publishing Company Ltd. All rights reserved. Not to be copied, transmitted or recorded in any way, in whole or part, without prior permission of the publishers.

Remediation of soil contaminated with dioxins by subcritical water extraction.

PubMed

Hashimoto, Shunji; Watanabe, Kiyohiko; Nose, Kazutoshi; Morita, Masatoshi

2004-01-01

The effectiveness of subcritical water extraction (SCWE) was examined for removing dioxins from contaminated soil. Most dioxins in the soil sample were reduced at 300 degrees C or more, but decreased dioxin concentrations were also observed at 150 degrees C. After 4 h of extraction, 99.4%, 94.5% and 60% of PCDDs were removed from samples at 350, 300 and 150 degrees C, respectively. It was also determined that degradation of dioxins had occurred, since the sum of dioxins in the soil plus water extracts after the experiments had considerably decreased. This study revealed that pressurizing is not essential for the removal of dioxins. Reduction was complete within 30 min at 350 degrees C; however, it took a much longer time at lower temperatures. The results of addition experiments in which OCDDs were added to different types of soil samples have shown that dechlorination is one of the major reaction pathways. After addition of OCDD to soil samples, experiments were carried out to examine in detail the degradation pathways of PCDDs. The removal rates and congener profiles varied among soil types. Although it was previously assumed that removal rates and congener profiles depended on the chemical components in soil, nonparametric statistical analysis revealed no significant relationship between the rate of reduction and elements present in the soil. It was confirmed from isomer patterns that dechlorination of the 2,3,7,8-positions in PCDDs takes place somewhat faster than for the 1,4,6,9-positions.

Exploiting Data Missingness in Bayesian Network Modeling

NASA Astrophysics Data System (ADS)

Rodrigues de Morais, Sérgio; Aussem, Alex

This paper proposes a framework built on the use of Bayesian networks (BN) for representing statistical dependencies between the existing random variables and additional dummy boolean variables, which represent the presence/absence of the respective random variable value. We show how augmenting the BN with these additional variables helps pinpoint the mechanism through which missing data contributes to the classification task. The missing data mechanism is thus explicitly taken into account to predict the class variable using the data at hand. Extensive experiments on synthetic and real-world incomplete data sets reveals that the missingness information improves classification accuracy.

Chitin amendment increases soil suppressiveness toward plant pathogens and modulates the actinobacterial and oxalobacteraceal communities in an experimental agricultural field.

PubMed

Cretoiu, Mariana Silvia; Korthals, Gerard W; Visser, Johnny H M; van Elsas, Jan Dirk

2013-09-01

A long-term experiment on the effect of chitin addition to soil on the suppression of soilborne pathogens was set up and monitored for 8 years in an experimental field, Vredepeel, The Netherlands. Chitinous matter obtained from shrimps was added to soil top layers on two different occasions, and the suppressiveness of soil toward Verticillium dahliae, as well as plant-pathogenic nematodes, was assessed, in addition to analyses of the abundances and community structures of members of the soil microbiota. The data revealed that chitin amendment had raised the suppressiveness of soil, in particular toward Verticillium dahliae, 9 months after the (second) treatment, extending to 2 years following treatment. Moreover, major effects of the added chitin on the soil microbial communities were detected. First, shifts in both the abundances and structures of the chitin-treated soil microbial communities, both of total soil bacteria and fungi, were found. In addition, the abundances and structures of soil actinobacteria and the Oxalobacteraceae were affected by chitin. At the functional gene level, the abundance of specific (family-18 glycoside hydrolase) chitinase genes carried by the soil bacteria also revealed upshifts as a result of the added chitin. The effects of chitin noted for the Oxalobacteraceae were specifically related to significant upshifts in the abundances of the species Duganella violaceinigra and Massilia plicata. These effects of chitin persisted over the time of the experiment.

Chitin Amendment Increases Soil Suppressiveness toward Plant Pathogens and Modulates the Actinobacterial and Oxalobacteraceal Communities in an Experimental Agricultural Field

PubMed Central

Cretoiu, Mariana Silvia; Korthals, Gerard W.; Visser, Johnny H. M.

2013-01-01

A long-term experiment on the effect of chitin addition to soil on the suppression of soilborne pathogens was set up and monitored for 8 years in an experimental field, Vredepeel, The Netherlands. Chitinous matter obtained from shrimps was added to soil top layers on two different occasions, and the suppressiveness of soil toward Verticillium dahliae, as well as plant-pathogenic nematodes, was assessed, in addition to analyses of the abundances and community structures of members of the soil microbiota. The data revealed that chitin amendment had raised the suppressiveness of soil, in particular toward Verticillium dahliae, 9 months after the (second) treatment, extending to 2 years following treatment. Moreover, major effects of the added chitin on the soil microbial communities were detected. First, shifts in both the abundances and structures of the chitin-treated soil microbial communities, both of total soil bacteria and fungi, were found. In addition, the abundances and structures of soil actinobacteria and the Oxalobacteraceae were affected by chitin. At the functional gene level, the abundance of specific (family-18 glycoside hydrolase) chitinase genes carried by the soil bacteria also revealed upshifts as a result of the added chitin. The effects of chitin noted for the Oxalobacteraceae were specifically related to significant upshifts in the abundances of the species Duganella violaceinigra and Massilia plicata. These effects of chitin persisted over the time of the experiment. PMID:23811512

Phosphate-Induced Immobilization of Uranium in Hanford Sediments.

PubMed

Pan, Zezhen; Giammar, Daniel E; Mehta, Vrajesh; Troyer, Lyndsay D; Catalano, Jeffrey G; Wang, Zheming

2016-12-20

Phosphate can be added to subsurface environments to immobilize U(VI) contamination. The efficacy of immobilization depends on the site-specific groundwater chemistry and aquifer sediment properties. Batch and column experiments were performed with sediments from the Hanford 300 Area in Washington State and artificial groundwater prepared to emulate the conditions at the site. Batch experiments revealed enhanced U(VI) sorption with increasing phosphate addition. X-ray absorption spectroscopy measurements of samples from the batch experiments found that U(VI) was predominantly adsorbed at conditions relevant to the column experiments and most field sites (low U(VI) loadings, <25 μM), and U(VI) phosphate precipitation occurred only at high initial U(VI) (>25 μM) and phosphate loadings. While batch experiments showed the transition of U(VI) uptake from adsorption to precipitation, the column study was more directly relevant to the subsurface environment because of the high solid:water ratio in the column and the advective flow of water. In column experiments, nearly six times more U(VI) was retained in sediments when phosphate-containing groundwater was introduced to U(VI)-loaded sediments than when the groundwater did not contain phosphate. This enhanced retention persisted for at least one month after cessation of phosphate addition to the influent fluid. Sequential extractions and laser-induced fluorescence spectroscopy of sediments from the columns suggested that the retained U(VI) was primarily in adsorbed forms. These results indicate that in situ remediation of groundwater by phosphate addition provides lasting benefit beyond the treatment period via enhanced U(VI) adsorption to sediments.

Vitamin Requirements of Several Cellulolytic Rumen Bacteria1

PubMed Central

Scott, H. W.; Dehority, B. A.

1965-01-01

Scott, H. W. (Ohio Agricultural Experiment Station, Wooster), and B. A. Dehority. Vitamin requirements of several cellulolytic rumen bacteria. J. Bacteriol. 89:1169–1175. 1965.—Four strains of cellulolytic bacteria recently isolated from in vitro rumen fermentations were used in this study. Nine water-soluble vitamins were tested in single-deletion and single-addition plus biotin experiments, each with and without charcoal-extracted casein hydrolysate. Bacteroides succinogenes A3C and B21a required only biotin under the above experimental conditions. Ruminococcus flavefaciens B34b showed an absolute requirement for biotin and was stimulated by p-aminobenzoic acid (PABA) in the single-deletion experiments. In the single-addition plus biotin experiments, PABA and, to a lesser extent, vitamin B12 appeared to be required for maximal growth. The presence or absence of casein hydrolysate did not affect the vitamin requirements for the aforementioned three strains. In the single-deletion experiments, R. flavefaciens Cla showed an absolute requirement for biotin and, when casein hydrolysate was omitted, for B12. When casein hydrolysate was present, no requirement for B12 could be observed. In the single-addition experiments where the basal medium contained biotin and casein hydrolysate or B12, PABA was required for maximal growth; however, the single deletion of PABA caused only slight retardation of growth. Investigation of the B12 or casein hydrolysate requirement of Cla revealed that a mixture of purified amino acids simulating casein hydrolysate satisfied this requirement. Subsequent work indicated that this requirement could be satisfied by the amino acid methionine. PMID:14292981

Phosphate-Induced Immobilization of Uranium in Hanford Sediments

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

Pan, Zezhen; Giammar, Daniel E.; Mehta, Vrajesh

2016-12-20

Phosphate can be added to subsurface environments to immobilize U(VI) contamination. The efficacy of immobilization depends on the site-specific groundwater chemistry and aquifer sediment properties. Batch and column experiments were performed with sediments from the Hanford 300 Area in Washington State and artificial groundwater prepared to emulate the conditions at the site. Batch experiments revealed enhanced U(VI) sorption with increasing phosphate addition. X-ray absorption spectroscopy measurements of samples from the batch experiments found that U(VI) was predominantly adsorbed at conditions relevant to the column experiments and most field sites (low U(VI) loadings, <25 μM), and U(VI) phosphate precipitation occurred onlymore » at high initial U(VI) (>25 μM) and phosphate loadings. While batch experiments showed the transition of U(VI) uptake from adsorption to precipitation, the column study was more directly relevant to the subsurface environment because of the high solid:water ratio in the column and the advective flow of water. In column experiments, nearly six times more U(VI) was retained in sediments when phosphate-containing groundwater was introduced to U(VI)-loaded sediments than when the groundwater did not contain phosphate. This enhanced retention persisted for at least one month after cessation of phosphate addition to the influent fluid. Sequential extractions and laser-induced fluorescence spectroscopy of sediments from the columns suggested that the retained U(VI) was primarily in adsorbed forms. These results indicate that in situ remediation of groundwater by phosphate addition provides lasting benefit beyond the treatment period via enhanced U(VI) adsorption to sediments.« less

Phosphate-Induced Immobilization of Uranium in Hanford Sediments

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

Pan, Zezhen; Giammar, Daniel E.; Mehta, Vrajesh

2016-12-20

Phosphate can be added to subsurface environments to immobilize U(VI) contamination. The efficacy of immobilization depends on the site-specific groundwater chemistry and aquifer sediment properties. Batch and column experiments were performed with sediments from the Hanford 300 Area in Washington State and artificial groundwater prepared to emulate the conditions at the site. Batch experiments revealed enhanced U(VI) sorption with increasing phosphate addition. X-ray absorption spectroscopy measurements of samples from the batch experiments found that U(VI) was predominantly adsorbed at conditions relevant to the column experiments and most field sites (low U(VI) loadings, <25 μM), and U(VI) phosphate precipitation occurred onlymore » at high initial U(VI) (>25μM) and phosphate loadings. While batch experiments showed the transition of U(VI) uptake from adsorption to precipitation, the column study was more directly relevant to the subsurface environment because of the high solid:water ratio in the column and the advective flow of water. In column experiments, nearly six times more U(VI) was retained in sediments when phosphate-containing groundwater was introduced to U(VI)-loaded sediments than when the groundwater did not contain phosphate. This enhanced retention persisted for at least one month after cessation of phosphate addition to the influent fluid. Sequential extractions and laser-induced fluorescence spectroscopy of sediments from the columns suggested that the retained U(VI) was primarily in adsorbed forms. These results indicate that in situ remediation of groundwater by phosphate addition provides lasting benefit beyond the treatment period via enhanced U(VI) adsorption to sediments.« less

Doing it differently: attempts to improve Millikan's oil-drop experiment

NASA Astrophysics Data System (ADS)

Heering, Peter; Klassen, Stephen

2010-07-01

Millikan's oil-drop experiment is one of the classic experiments from the history of physics. Due to its content (the determination of the elementary charge) it is also among those experiments that are frequently used and discussed in teaching situations. Disappointingly, a review of the educational literature on this experiment reveals that its implementation in teaching situations is not especially successful. Using a collaborative approach, we have attempted to develop an understanding of the difficulties that students encounter with this experiment. In our approach, apart from evaluating students' lab reports, we used questionnaires and semi-structured interviews. Additionally, we have used the historical development of the oil-drop experiment as a resource for restructuring the educational use of the experiment, and we have attempted to develop a more thorough understanding of the experiment through an analysis of the data generated in the experiment and its mathematical treatment. As a result, we suggest a different use of the apparatus that appears to result in less frustration of the students as well as a better understanding of the experiment and its difficulties by the students.

Voluntary or involuntary? A neurophysiologic approach to functional movement disorders.

PubMed

Stenner, M-P; Haggard, P

2016-01-01

Patients with functional movement disorders (FMD) experience movements as involuntary that share fundamental characteristics with voluntary actions. This apparent paradox raises questions regarding the possible sources of a subjective experience of action. In addition, it poses a yet unresolved diagnostic challenge, namely how to describe or even quantify this experience in a scientifically and clinically useful way. Here, we describe recent experimental approaches that have shed light on the phenomenology of action in FMD. We first outline the sources and content of a subjective experience of action in healthy humans and discuss how this experience may be created in the brain. Turning to FMD, we describe implicit, behavioral measures that have revealed specific abnormalities in the awareness of action in FMD. Based on these abnormalities, we propose a potential, new solution to the paradox of volition in FMD. © 2016 Elsevier B.V. All rights reserved.

Polyfibroblast: A Self-Healing and Galvanic Protection Additive

DTIC Science & Technology

2011-04-25

of premature microcapsule rupture, and have shown that the microcapsules are resilient to solvent soaking. 2 Project Goals and Objectives This month...capability of Polyfibroblast microcapsules , we designed the following test. We short-circuited a A1008 steel specimen to a strip of polyurethane...pH New experiments have revealed that alkaline plating baths etch the polymer skin layer. Fresh microcapsules placed in plating baths with a pH of

Vicarious Social Touch Biases Gazing at Faces and Facial Emotions.

PubMed

Schirmer, Annett; Ng, Tabitha; Ebstein, Richard P

2018-02-01

Research has suggested that interpersonal touch promotes social processing and other-concern, and that women may respond to it more sensitively than men. In this study, we asked whether this phenomenon would extend to third-party observers who experience touch vicariously. In an eye-tracking experiment, participants (N = 64, 32 men and 32 women) viewed prime and target images with the intention of remembering them. Primes comprised line drawings of dyadic interactions with and without touch. Targets comprised two faces shown side-by-side, with one being neutral and the other being happy or sad. Analysis of prime fixations revealed that faces in touch interactions attracted longer gazing than faces in no-touch interactions. In addition, touch enhanced gazing at the area of touch in women but not men. Analysis of target fixations revealed that touch priming increased looking at both faces immediately after target onset, and subsequently, at the emotional face in the pair. Sex differences in target processing were nonsignificant. Together, the present results imply that vicarious touch biases visual attention to faces and promotes emotion sensitivity. In addition, they suggest that, compared with men, women are more aware of tactile exchanges in their environment. As such, vicarious touch appears to share important qualities with actual physical touch. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

The Streptococcus pyogenes serotype M49 Nra-Ralp3 transcriptional regulatory network and its control of virulence factor expression from the novel eno ralp3 epf sagA pathogenicity region.

PubMed

Kreikemeyer, Bernd; Nakata, Masanobu; Köller, Thomas; Hildisch, Hendrikje; Kourakos, Vassilios; Standar, Kerstin; Kawabata, Shigetada; Glocker, Michael O; Podbielski, Andreas

2007-12-01

Many Streptococcus pyogenes (group A streptococcus [GAS]) virulence factor- and transcriptional regulator-encoding genes cluster together in discrete genomic regions. Nra is a central regulator of the FCT region. Previous studies exclusively described Nra as a transcriptional repressor of adhesin and toxin genes. Here transcriptome and proteome analysis of a serotype M49 GAS strain and an isogenic Nra mutant of this strain revealed the complete Nra regulon profile. Nra is active in all growth phases tested, with the largest regulon in the transition phase. Almost exclusively, virulence factor-encoding genes are repressed by Nra; these genes include the GAS pilus operon, the capsule synthesis operon, the cytolysin-mediated translocation system genes, all Mga region core virulence genes, and genes encoding other regulators, like the Ihk/Irr system, Rgg, and two additional RofA-like protein family regulators. Surprisingly, our experiments revealed that Nra additionally acts as a positive regulator, mostly for genes encoding proteins and enzymes with metabolic functions. Epidemiological investigations revealed strong genetic linkage of one particular Nra-repressed regulator, Ralp3 (SPy0735), with a gene encoding Epf (extracellular protein factor from Streptococcus suis). In a serotype-specific fashion, this ralp3 epf gene block is integrated, most likely via transposition, into the eno sagA virulence gene block, which is present in all GAS serotypes. In GAS serotypes M1, M4, M12, M28, and M49 this novel discrete genetic region is therefore designated the eno ralp3 epf sagA (ERES) pathogenicity region. Functional experiments showed that Epf is a novel GAS plasminogen-binding protein and revealed that Ralp3 activity counteracts Nra and MsmR regulatory activity. In addition to the Mga and FCT regions, the ERES region is the third discrete chromosomal pathogenicity region. All of these regions are transcriptionally linked, adding another level of complexity to the known GAS growth phase-dependent regulatory network.

The Streptococcus pyogenes Serotype M49 Nra-Ralp3 Transcriptional Regulatory Network and Its Control of Virulence Factor Expression from the Novel eno ralp3 epf sagA Pathogenicity Region▿ †

PubMed Central

Kreikemeyer, Bernd; Nakata, Masanobu; Köller, Thomas; Hildisch, Hendrikje; Kourakos, Vassilios; Standar, Kerstin; Kawabata, Shigetada; Glocker, Michael O.; Podbielski, Andreas

2007-01-01

Many Streptococcus pyogenes (group A streptococcus [GAS]) virulence factor- and transcriptional regulator-encoding genes cluster together in discrete genomic regions. Nra is a central regulator of the FCT region. Previous studies exclusively described Nra as a transcriptional repressor of adhesin and toxin genes. Here transcriptome and proteome analysis of a serotype M49 GAS strain and an isogenic Nra mutant of this strain revealed the complete Nra regulon profile. Nra is active in all growth phases tested, with the largest regulon in the transition phase. Almost exclusively, virulence factor-encoding genes are repressed by Nra; these genes include the GAS pilus operon, the capsule synthesis operon, the cytolysin-mediated translocation system genes, all Mga region core virulence genes, and genes encoding other regulators, like the Ihk/Irr system, Rgg, and two additional RofA-like protein family regulators. Surprisingly, our experiments revealed that Nra additionally acts as a positive regulator, mostly for genes encoding proteins and enzymes with metabolic functions. Epidemiological investigations revealed strong genetic linkage of one particular Nra-repressed regulator, Ralp3 (SPy0735), with a gene encoding Epf (extracellular protein factor from Streptococcus suis). In a serotype-specific fashion, this ralp3 epf gene block is integrated, most likely via transposition, into the eno sagA virulence gene block, which is present in all GAS serotypes. In GAS serotypes M1, M4, M12, M28, and M49 this novel discrete genetic region is therefore designated the eno ralp3 epf sagA (ERES) pathogenicity region. Functional experiments showed that Epf is a novel GAS plasminogen-binding protein and revealed that Ralp3 activity counteracts Nra and MsmR regulatory activity. In addition to the Mga and FCT regions, the ERES region is the third discrete chromosomal pathogenicity region. All of these regions are transcriptionally linked, adding another level of complexity to the known GAS growth phase-dependent regulatory network. PMID:17893125

Activity-Induced Remodeling of Olfactory Bulb Microcircuits Revealed by Monosynaptic Tracing

PubMed Central

Arenkiel, Benjamin R.; Hasegawa, Hiroshi; Yi, Jason J.; Larsen, Rylan S.; Wallace, Michael L.; Philpot, Benjamin D.; Wang, Fan; Ehlers, Michael D.

2011-01-01

The continued addition of new neurons to mature olfactory circuits represents a remarkable mode of cellular and structural brain plasticity. However, the anatomical configuration of newly established circuits, the types and numbers of neurons that form new synaptic connections, and the effect of sensory experience on synaptic connectivity in the olfactory bulb remain poorly understood. Using in vivo electroporation and monosynaptic tracing, we show that postnatal-born granule cells form synaptic connections with centrifugal inputs and mitral/tufted cells in the mouse olfactory bulb. In addition, newly born granule cells receive extensive input from local inhibitory short axon cells, a poorly understood cell population. The connectivity of short axon cells shows clustered organization, and their synaptic input onto newborn granule cells dramatically and selectively expands with odor stimulation. Our findings suggest that sensory experience promotes the synaptic integration of new neurons into cell type-specific olfactory circuits. PMID:22216277

Middle School Students' Science Self-Efficacy and Its Sources: Examination of Gender Difference

NASA Astrophysics Data System (ADS)

Kıran, Dekant; Sungur, Semra

2012-10-01

The main purpose of the present study is to investigate middle school students' science self-efficacy as well as its sources and outcomes as a function of gender. Bandura's hypothesized sources of self-efficacy (i.e., mastery experience, vicarious experience, verbal persuasion, and emotional arousal) in addition to being inviting with self and inviting with others were examined as sources of self-efficacy, while cognitive and metacognitive strategy use was examined as an outcome of self-efficacy. A total of 1,932 students participated in the study and were administered self-report instruments. Results showed that the relationship between science self-efficacy and its proposed sources does not change as a function of gender. All proposed sources, except for vicarious experience, were found to be significantly related to students' scientific self-efficacy. Moreover, girls were found to experience significantly more emotional arousal and to send positive messages to others more than boys. On the other hand, no gender difference was found concerning science self-efficacy and strategy use. The findings also revealed a positive association between science self-efficacy and strategy use. Overall, findings supported Bandura's conception of self-efficacy and suggested invitations as additional sources of self-efficacy.

[Estimates of the size of inhibitory areas in crowding effects in periphery].

PubMed

Bondarko, V M; Danilova, M V; Solnushkin, S D; Chikhman, V N

2014-01-01

In psychophysical experiments we studied how surround influences recognition of test objects. The tests were low-contrast Landolt rings of the size 1.1, 1.5 and 2.3 deg. Their centers were located at 13.2 deg from the fixation point. The additional objects were similar Landolt rings or rings without gaps. The distance between the centers of the test and the additional objects varied from 2.2 to 13.2 deg. Inone experiment, the task of the observer was to identify both the test objects and the surrounding objects. In the second experiment the stimulus layout was the same, but'identification of only the test stimulus was required. In both experiments, deterioration of performance was found at all distances between the test objects and the surround, but the deterioration was more significant when the observer carried out the dual task. The data showed that the size of the inhibitory areas in our case does not comply with the Bouma low which states that the size of the interaction areas are equal to half of the eccentricity where the test is presented. Further deterioration of performance in the dual task reveals the contribution of attention into peripheral crowding effects.

Grounded Learning Experience: Helping Students Learn Physics through Visuo-Haptic Priming and Instruction

NASA Astrophysics Data System (ADS)

Huang, Shih-Chieh Douglas

In this dissertation, I investigate the effects of a grounded learning experience on college students' mental models of physics systems. The grounded learning experience consisted of a priming stage and an instruction stage, and within each stage, one of two different types of visuo-haptic representation was applied: visuo-gestural simulation (visual modality and gestures) and visuo-haptic simulation (visual modality, gestures, and somatosensory information). A pilot study involving N = 23 college students examined how using different types of visuo-haptic representation in instruction affected people's mental model construction for physics systems. Participants' abilities to construct mental models were operationalized through their pretest-to-posttest gain scores for a basic physics system and their performance on a transfer task involving an advanced physics system. Findings from this pilot study revealed that, while both simulations significantly improved participants' mental modal construction for physics systems, visuo-haptic simulation was significantly better than visuo-gestural simulation. In addition, clinical interviews suggested that participants' mental model construction for physics systems benefited from receiving visuo-haptic simulation in a tutorial prior to the instruction stage. A dissertation study involving N = 96 college students examined how types of visuo-haptic representation in different applications support participants' mental model construction for physics systems. Participant's abilities to construct mental models were again operationalized through their pretest-to-posttest gain scores for a basic physics system and their performance on a transfer task involving an advanced physics system. Participants' physics misconceptions were also measured before and after the grounded learning experience. Findings from this dissertation study not only revealed that visuo-haptic simulation was significantly more effective in promoting mental model construction and remedying participants' physics misconceptions than visuo-gestural simulation, they also revealed that visuo-haptic simulation was more effective during the priming stage than during the instruction stage. Interestingly, the effects of visuo-haptic simulation in priming and visuo-haptic simulation in instruction on participants' pretest-to-posttest gain scores for a basic physics system appeared additive. These results suggested that visuo-haptic simulation is effective in physics learning, especially when it is used during the priming stage.

Demixing-stimulated lane formation in binary complex plasma

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

Du, C.-R.; Jiang, K.; Suetterlin, K. R.

2011-11-29

Recently lane formation and phase separation have been reported for experiments with binary complex plasmas in the PK3-Plus laboratory onboard the International Space Station (ISS). Positive non-additivity of particle interactions is known to stimulate phase separation (demixing), but its effect on lane formation is unknown. In this work, we used Langevin dynamics (LD) simulation to probe the role of non-additivity interactions on lane formation. The competition between laning and demixing leads to thicker lanes. Analysis based on anisotropic scaling indices reveals a crossover from normal laning mode to a demixing-stimulated laning mode. Extensive numerical simulations enabled us to identify amore » critical value of the non-additivity parameter {Delta} for the crossover.« less

Apoptin towards safe and efficient anticancer therapies.

PubMed

Backendorf, Claude; Noteborn, Mathieu H M

2014-01-01

The chicken anemia virus derived protein apoptin harbors cancer-selective cell killing characteristics, essentially based on phosphorylation-mediated nuclear transfer in cancer cells and efficient cytoplasmic degradation in normal cells. Here, we describe a growing set of preclinical experiments underlying the promises of the anti-cancer potential of apoptin. Various non-replicative oncolytic viral vector systems have revealed the safety and efficacy of apoptin. In addition, apoptin enhanced the oncolytic potential of adenovirus, parvovirus and Newcastle disease virus vectors. Intratumoral injection of attenuated Salmonella typhimurium bacterial strains and plasmid-based systems expressing apoptin resulted in significant tumor regression. In-vitro and in-vivo experiments showed that recombinant membrane-transferring PTD4- or TAT-apoptin proteins have potential as a future anticancer therapeutics. In xenografted hepatoma and melanoma mouse models PTD4-apoptin protein entered both cancer and normal cells, but only killed cancer cells. Combinatorial treatment of PTD4-apoptin with various (chemo)therapeutic compounds revealed an additive or even synergistic effect, reducing the side effects of the single (chemo)therapeutic treatment. Degradable polymeric nanocapsules harboring MBP-apoptin fusion-protein induced tumor-selective cell killing in-vitro and in-vivo and revealed the potential of polymer-apoptin protein vehicles as an anticancer agent.Besides its direct use as an anticancer therapeutic, apoptin research has also generated novel possibilities for drug design. The nuclear location domains of apoptin are attractive tools for targeting therapeutic compounds into the nucleus of cancer cells. Identification of cancer-related processes targeted by apoptin can potentially generate novel drug targets. Recent breakthroughs important for clinical applications are reported inferring apoptin-based clinical trials as a feasible reality.

Specific Connectivity and Unique Molecular Identity of MET Receptor Tyrosine Kinase Expressing Serotonergic Neurons in the Caudal Dorsal Raphe Nuclei.

PubMed

Kast, Ryan J; Wu, Hsiao-Huei; Williams, Piper; Gaspar, Patricia; Levitt, Pat

2017-05-17

Molecular characterization of neurons across brain regions has revealed new taxonomies for understanding functional diversity even among classically defined neuronal populations. Neuronal diversity has become evident within the brain serotonin (5-HT) system, which is far more complex than previously appreciated. However, until now it has been difficult to define subpopulations of 5-HT neurons based on molecular phenotypes. We demonstrate that the MET receptor tyrosine kinase (MET) is specifically expressed in a subset of 5-HT neurons within the caudal part of the dorsal raphe nuclei (DRC) that is encompassed by the classic B6 serotonin cell group. Mapping from embryonic day 16 through adulthood reveals that MET is expressed almost exclusively in the DRC as a condensed, paired nucleus, with an additional sparse set of MET+ neurons scattered within the median raphe. Retrograde tracing experiments reveal that MET-expressing 5-HT neurons provide substantial serotonergic input to the ventricular/subventricular region that contains forebrain stem cells, but do not innervate the dorsal hippocampus or entorhinal cortex. Conditional anterograde tracing experiments show that 5-HT neurons in the DRC/B6 target additional forebrain structures such as the medial and lateral septum and the ventral hippocampus. Molecular neuroanatomical analysis identifies 14 genes that are enriched in DRC neurons, including 4 neurotransmitter/neuropeptide receptors and 2 potassium channels. These analyses will lead to future studies determining the specific roles that 5-HT MET+ neurons contribute to the broader set of functions regulated by the serotonergic system.

Bidirectional, temporal associations of sleep with positive events, affect, and stressors in daily life across a week

PubMed Central

Sin, Nancy L.; Almeida, David M.; Crain, Tori L.; Kossek, Ellen Ernst; Berkman, Lisa F.; Buxton, Orfeu M.

2017-01-01

Background Sleep is intricately tied to emotional well-being, yet little is known about the reciprocal links between sleep and psychosocial experiences in the context of daily life. Purpose To evaluate daily psychosocial experiences (positive and negative affect, positive events, and stressors) as predictors of same-night sleep quality and duration, in addition to the reversed associations of nightly sleep predicting next-day experiences. Methods Daily experiences and self-reported sleep were assessed via telephone interviews for eight consecutive evenings in two replicate samples of U.S. employees (131 higher-income professionals and 181 lower-income hourly workers). Multilevel models evaluated within-person associations of daily experiences with sleep quality and duration. Analyses controlled for demographics, insomnia symptoms, the previous day’s experiences and sleep measures, and additional day-level covariates. Results Daily positive experiences were associated with improved as well as disrupted subsequent sleep. Specifically, positive events at home predicted better sleep quality in both samples, whereas greater positive affect was associated with shorter sleep duration among the higher-income professionals. Negative affect and stressors were unrelated to subsequent sleep. Results for the reversed direction revealed that better sleep quality (and, to a lesser degree, longer sleep duration) predicted emotional well-being and lower odds of encountering stressors on the following day. Conclusions Given the reciprocal relationships between sleep and daily experiences, efforts to improve well-being in daily life should reflect the importance of sleep. PMID:28188584

Bidirectional, Temporal Associations of Sleep with Positive Events, Affect, and Stressors in Daily Life Across a Week.

PubMed

Sin, Nancy L; Almeida, David M; Crain, Tori L; Kossek, Ellen Ernst; Berkman, Lisa F; Buxton, Orfeu M

2017-06-01

Sleep is intricately tied to emotional well-being, yet little is known about the reciprocal links between sleep and psychosocial experiences in the context of daily life. The aim of this study is to evaluate daily psychosocial experiences (positive and negative affect, positive events, and stressors) as predictors of same-night sleep quality and duration, in addition to the reversed associations of nightly sleep predicting next-day experiences. Daily experiences and self-reported sleep were assessed via telephone interviews for eight consecutive evenings in two replicate samples of US employees (131 higher-income professionals and 181 lower-income hourly workers). Multilevel models evaluated within-person associations of daily experiences with sleep quality and duration. Analyses controlled for demographics, insomnia symptoms, the previous day's experiences and sleep measures, and additional day-level covariates. Daily positive experiences were associated with improved as well as disrupted subsequent sleep. Specifically, positive events at home predicted better sleep quality in both samples, whereas greater positive affect was associated with shorter sleep duration among the higher-income professionals. Negative affect and stressors were unrelated to subsequent sleep. Results for the reversed direction revealed that better sleep quality (and, to a lesser degree, longer sleep duration) predicted emotional well-being and lower odds of encountering stressors on the following day. Given the reciprocal relationships between sleep and daily experiences, efforts to improve well-being in daily life should reflect the importance of sleep.

First learned words are not forgotten: Age-of-acquisition effects in the tip-of-the-tongue experience.

PubMed

Navarrete, Eduardo; Pastore, Massimiliano; Valentini, Rosa; Peressotti, Francesca

2015-10-01

A large body of evidence indicates that the age at which a word is acquired predicts the time required to retrieve that word during speech production. Here we explored whether age of acquisition also predicts the experience of being unable to produce a known word at a particular moment. Italian speakers named a sequence of pictures in Experiment 1 or retrieved a word as a response to a definition in Experiment 2. In both experiments, the participants were instructed to indicate when they were in a tip-of-the-tongue (TOT) state. Generalized mixed-effects models performed on the TOT and correct responses revealed that word frequency and age of acquisition predicted the TOT states. Specifically, low-frequency words elicited more TOTs than did high-frequency words, replicating previous findings. In addition, late-acquired words elicited more TOTs than did early-acquired words. Further analyses revealed that the age of acquisition was a better predictor of TOTs than was word frequency. The effects of age of acquisition were similar with subjective and objective measures of age of acquisition, and persisted when several psycholinguistic variables were taken into consideration as predictors in the generalized mixed-effects models. We explained these results in terms of weaker semantic-to-phonological connections in the speech production system for late-acquired words.

The proximal experience of gratitude.

PubMed

Layous, Kristin; Sweeny, Kate; Armenta, Christina; Na, Soojung; Choi, Incheol; Lyubomirsky, Sonja

2017-01-01

Although a great deal of research has tested the longitudinal effects of regularly practicing gratitude, much less attention has been paid to the emotional landscape directly following engagement in gratitude exercises. In three studies, we explored the array of discrete emotions people experience after being prompted to express or recall gratitude. In Studies 1 and 2, two different gratitude exercises produced not only greater feelings of gratitude relative to two positive emotion control conditions (i.e., recalling relief), but also higher levels of other socially relevant states like elevation, connectedness, and indebtedness. In a third study, conducted in both the U.S. and S. Korea, we compared a gratitude exercise to another positive emotion elicitation (i.e., recalling a kind act) and to a neutral task, and again found that the gratitude exercise prompted greater gratitude, elevation, indebtedness, and guilt, but no more embarrassment or shame, than the two comparison conditions. Additionally, in all three studies, emodiversity and cluster analyses revealed that gratitude exercises led to the simultaneous experience of both pleasant and unpleasant socially-relevant states. In sum, although it may seem obvious that gratitude exercises would evoke grateful, positive states, a meta-analysis of our three studies revealed that gratitude exercises actually elicit a mixed emotional experience-one that simultaneously leads individuals to feel uplifted and indebted.

Nitrous oxide emission reduction in temperate biochar-amended soils

NASA Astrophysics Data System (ADS)

Felber, R.; Hüppi, R.; Leifeld, J.; Neftel, A.

2012-01-01

Biochar, a pyrolysis product of organic residues, is an amendment for agricultural soils to improve soil fertility, sequester CO2 and reduce greenhouse gas (GHG) emissions. In highly weathered tropical soils laboratory incubations of soil-biochar mixtures revealed substantial reductions for nitrous oxide (N2O) and carbon dioxide (CO2). In contrast, evidence is scarce for temperate soils. In a three-factorial laboratory incubation experiment two different temperate agricultural soils were amended with green waste and coffee grounds biochar. N2O and CO2 emissions were measured at the beginning and end of a three month incubation. The experiments were conducted under three different conditions (no additional nutrients, glucose addition, and nitrate and glucose addition) representing different field conditions. We found mean N2O emission reductions of 60 % compared to soils without addition of biochar. The reduction depended on biochar type and soil type as well as on the age of the samples. CO2 emissions were slightly reduced, too. NO3- but not NH4+ concentrations were significantly reduced shortly after biochar incorporation. Despite the highly significant suppression of N2O emissions biochar effects should not be transferred one-to-one to field conditions but need to be tested accordingly.

Static and kinetic studies of calmodulin and melittin complex.

PubMed

Itakura, M; Iio, T

1992-08-01

Ca2+ binding to calmodulin triggers conformational change of the protein which induces exposure of hydrophobic surfaces. Melittin has been believed to bind to Ca(2+)-bound calmodulin through the exposed hydrophobic surfaces. However, tryptophan fluorescence measurements and gel chromatography experiments with the melittin-calmodulin system revealed that melittin bound to calmodulin at zero salt concentration even in the absence of Ca2+; addition of salt removed melittin from Ca(2+)-free calmodulin. This means not only the hydrophobic interaction but also the electrostatic interaction contributes to the melittin-calmodulin binding. The fluorescence stopped-flow studies of the dissociation reaction of melittin-calmodulin complex revealed that Ca2+ removal from the complex induced a conformational change of calmodulin, resulting in reduction of the hydrophobic interaction between melittin and calmodulin, but the electrostatic interaction kept melittin still bound to calmodulin for a subsecond lag period, after which melittin dissociated from calmodulin. The fluorescence stopped-flow experiments on the dissociation reaction of complex of melittin and tryptic fragment(s) of calmodulin revealed that the lag period of the melittin dissociation reaction was attributable to the interaction between the C-terminal half of calmodulin and the C-terminal region of melittin.

Phenotypic plasticity in female mate choice behavior is mediated by an interaction of direct and indirect genetic effects in Drosophila melanogaster.

PubMed

Filice, David C S; Long, Tristan A F

2017-05-01

Female mate choice is a complex decision-making process that involves many context-dependent factors. In Drosophila melanogaster , a model species for the study of sexual selection, indirect genetic effects (IGEs) of general social interactions can influence female mate choice behaviors, but the potential impacts of IGEs associated with mating experiences are poorly understood. Here, we examined whether the IGEs associated with a previous mating experience had an effect on subsequent female mate choice behaviors and quantified the degree of additive genetic variation associated with this effect. Females from 21 different genetic backgrounds were housed with males from one of two distinct genetic backgrounds for either a short (3 hr) or long (48 hr) exposure period and their subsequent mate choice behaviors were scored. We found that the genetic identity of a previous mate significantly influenced a female's subsequent interest in males and preference of males. Additionally, a hemiclonal analysis revealed significant additive genetic variation associated with experience-dependent mate choice behaviors, indicating a genotype-by-environment interaction for both of these parameters. We discuss the significance of these results with regard to the evolution of plasticity in female mate choice behaviors and the maintenance of variation in harmful male traits.

The Role of Adolescent Victimization in Energy Drink Consumption: Monitoring the Future, 2010-2016.

PubMed

Jackson, Dylan B; Leal, Wanda E; Posick, Chad; Vaughn, Michael G; Olivan, Myrah

2018-05-21

Energy drinks have been linked to a number of deleterious health outcomes among youth. Even so, the underlying risk factors for energy drink consumption among youth are less frequently examined. The present study examines the link between adolescent victimization experiences (i.e., property and violent victimization) and energy drink consumption among a nationally representative sample of adolescents. We employed the seven most recent cohorts (2010-2016) from the Monitoring the Future (MTF) study. A multi-stage random sampling technique was used to acquire the U.S. Youths reported the extent to which they consumed energy drinks. Additionally, three indicators of property victimization and four indicators of violent victimization were available in the data. The findings reveal a significant dose-response relationship between energy drink consumption and victimization. This relationship was especially pronounced among females. For instance, more than 52% of females with the highest count of various violent victimization experiences consumed energy drinks, which was three times the rate of females who had no previous violent victimization experiences. Practitioners who interact with adolescent victims may probe for energy drink usage in addition to other addictive substances such as alcohol, tobacco, and drugs. Additional scrutiny may also be in order in regulating the amount of caffeine and sugar allowed in these beverages.

Evaluation and optimization of hepatocyte culture media factors by design of experiments (DoE) methodology

PubMed Central

Dong, Jia; Lübberstedt, Marc; Urbaniak, Thomas; Nüssler, Andreas K.N.; Knobeloch, Daniel; Gerlach, Jörg C.; Zeilinger, Katrin

2008-01-01

Optimization of cell culture media based on statistical experimental design methodology is a widely used approach for improving cultivation conditions. We applied this methodology to refine the composition of an established culture medium for growth of a human hepatoma cell line, C3A. A selection of growth factors and nutrient supplements were systematically screened according to standard design of experiments (DoE) procedures. The results of the screening indicated that the medium additives hepatocyte growth factor, oncostatin M, and fibroblast growth factor 4 significantly influenced the metabolic activities of the C3A cell line. Surface response methodology revealed that the optimum levels for these factors were 30 ng/ml for hepatocyte growth factor and 35 ng/ml for oncostatin M. Additional experiments on primary human hepatocyte cultures showed high variance in metabolic activities between cells from different individuals, making determination of optimal levels of factors more difficult. Still, it was possible to conclude that hepatocyte growth factor, epidermal growth factor, and oncostatin M had decisive effects on the metabolic functions of primary human hepatocytes. PMID:19003182

Evaluation and optimization of hepatocyte culture media factors by design of experiments (DoE) methodology.

PubMed

Dong, Jia; Mandenius, Carl-Fredrik; Lübberstedt, Marc; Urbaniak, Thomas; Nüssler, Andreas K N; Knobeloch, Daniel; Gerlach, Jörg C; Zeilinger, Katrin

2008-07-01

Optimization of cell culture media based on statistical experimental design methodology is a widely used approach for improving cultivation conditions. We applied this methodology to refine the composition of an established culture medium for growth of a human hepatoma cell line, C3A. A selection of growth factors and nutrient supplements were systematically screened according to standard design of experiments (DoE) procedures. The results of the screening indicated that the medium additives hepatocyte growth factor, oncostatin M, and fibroblast growth factor 4 significantly influenced the metabolic activities of the C3A cell line. Surface response methodology revealed that the optimum levels for these factors were 30 ng/ml for hepatocyte growth factor and 35 ng/ml for oncostatin M. Additional experiments on primary human hepatocyte cultures showed high variance in metabolic activities between cells from different individuals, making determination of optimal levels of factors more difficult. Still, it was possible to conclude that hepatocyte growth factor, epidermal growth factor, and oncostatin M had decisive effects on the metabolic functions of primary human hepatocytes.

Comparative Genomic Analysis MERS CoV Isolated from Humans and Camels with Special Reference to Virus Encoded Helicase.

PubMed

Alnazawi, Mohamed; Altaher, Abdallah; Kandeel, Mahmoud

2017-01-01

Middle East Respiratory Syndrome Coronavirus (MERS CoV) is a new emerging viral disease characterized by high fatality rate. Understanding MERS CoV genetic aspects and codon usage pattern is important to understand MERS CoV survival, adaptation, evolution, resistance to innate immunity, and help in finding the unique aspects of the virus for future drug discovery experiments. In this work, we provide comprehensive analysis of 238 MERS CoV full genomes comprised of human (hMERS) and camel (cMERS) isolates of the virus. MERS CoV genome shaping seems to be under compositional and mutational bias, as revealed by preference of A/T over G/C nucleotides, preferred codons, nucleotides at the third position of codons (NT3s), relative synonymous codon usage, hydropathicity (Gravy), and aromaticity (Aromo) indices. Effective number of codons (ENc) analysis reveals a general slight codon usage bias. Codon adaptation index reveals incomplete adaptation to host environment. MERS CoV showed high ability to resist the innate immune response by showing lower CpG frequencies. Neutrality evolution analysis revealed a more significant role of mutation pressure in cMERS over hMERS. Correspondence analysis revealed that MERS CoV genomes have three genetic clusters, which were distinct in their codon usage, host, and geographic distribution. Additionally, virtual screening and binding experiments were able to identify three new virus-encoded helicase binding compounds. These compounds can be used for further optimization of inhibitors.

Near-death experiences and the temporal lobe.

PubMed

Britton, Willoughby B; Bootzin, Richard R

2004-04-01

Many studies in humans suggest that altered temporal lobe functioning, especially functioning in the right temporal lobe, is involved in mystical and religious experiences. We investigated temporal lobe functioning in individuals who reported having transcendental "near-death experiences" during life-threatening events. These individuals were found to have more temporal lobe epileptiform electroencephalographic activity than control subjects and also reported significantly more temporal lobe epileptic symptoms. Contrary to predictions, epileptiform activity was nearly completely lateralized to the left hemisphere. The near-death experience was not associated with dysfunctional stress reactions such as dissociation, posttraumatic stress disorder, and substance abuse, but rather was associated with positive coping styles. Additional analyses revealed that near-death experiencers had altered sleep patterns, specifically, a shorter duration of sleep and delayed REM sleep relative to the control group. These results suggest that altered temporal lobe functioning may be involved in the near-death experience and that individuals who have had such experiences are physiologically distinct from the general population.

TARDIS: An Automation Framework for JPL Mission Design and Navigation

NASA Technical Reports Server (NTRS)

Roundhill, Ian M.; Kelly, Richard M.

2014-01-01

Mission Design and Navigation at the Jet Propulsion Laboratory has implemented an automation framework tool to assist in orbit determination and maneuver design analysis. This paper describes the lessons learned from previous automation tools and how they have been implemented in this tool. In addition this tool has revealed challenges in software implementation, testing, and user education. This paper describes some of these challenges and invites others to share their experiences.

Preliminary Studies on Aerodynamic Control with Direct Current Discharge at Hypersonic Speed

NASA Astrophysics Data System (ADS)

Watanabe, Yasumasa; Takama, Yoshiki; Imamura, Osamu; Watanuki, Tadaharu; Suzuki, Kojiro

A new idea of an aerodynamic control device for hypersonic vehicles using plasma discharges is presented. The effect of DC plasma discharge on a hypersonic flow is examined with both experiments and CFD analyses. It is revealed that the surface pressure upstream of plasma area significantly increases, which would be preferable in realizing a new aerodynamic control devices. Such pressure rise is also observed in the result of analyses of the Navier-Stokes equations with energy addition that simulates the Joule heating of a plasma discharge. It is revealed that the pressure rise due to the existence of the plasma discharge can be qualitatively explained as an effect of Joule heating.

Peptidomics of prolyl endopeptidase in the central nervous system

PubMed Central

Nolte, Whitney M.; Tagore, Debarati M.; Lane, William S.; Saghatelian, Alan

2009-01-01

Prolyl endopeptidase (Prep) is a member of the prolyl peptidase family and is of interest due to its unique biochemistry and connections to cognitive function. Using an unbiased mass spectrometry (MS)-based peptidomics platform, we identified Prep regulated peptides in the central nervous system (CNS) of mice by measuring changes in the peptidome as a function of Prep activity. This approach was validated by the identification of known Prep substrates, such as the neuropeptide substance P and thymosin-β4, the precursor to the bioactive peptide Ac-SDKP. In addition to these known substrates, we also discovered that Prep regulates many additional peptides, including additional bioactive peptides and proline rich peptides (PRPs). Biochemical experiments confirmed that some of these Prep regulated peptides are indeed substrates of the enzyme. Moreover, these experiments also supported the known preference of Prep for shorter peptides, while revealing a previously unknown cleavage site specificity of Prep when processing certain multi-proline containing peptides, including PRPs. The discovery of Prep regulated peptides implicates Prep in new biological pathways and provides insights into the biochemistry of this enzyme. PMID:19911840

The effect of TBT on the structure of a marine sediment comunity--a Boxcosm study.

PubMed

Dahllöf, I; Agrenius, S; Blanck, H; Hall, P; Magnusson, K; Molander, S

2001-08-01

The effect of tri-n-butyl tin (TBT) on an intact marine sediment community after five months exposure was investigated. Changes in the structure of macro- and meiofauna communities were determined, as well as the functional diversity of the microbial community using BIOLOG microplates for Gram negative bacteria. Development of tolerance in the microbial community was investigated using Pollution Induced Community Tolerance (PICT) experiments with fluxes of nutrients as effect indicators. TBT affected the structure and recruitment of the macro- and meiofauna at nominal additions of 30-137 micromol TBT/m2 sediment. Number of species, diversity, biomass and community similarity was reduced at these concentrations compared to control. Species that molt seemed to be the most tolerant since they were predominant in boxes that had received the highest TBT addition and echinoderms were the most sensitive species. Renewed addition of TBT in PICT experiments with sediment from each boxcosm showed that TBT had an effect on individual nutrient fluxes from all sediments. Analyses of the flux patterns revealed a memory of previous TBT exposure, either due to induced tolerance or other community conditioning.

In situ investigation of complex BaSO4 fiber generation in the presence of sodium polyacrylate. 1. Kinetics and solution analysis.

PubMed

Wang, Tongxin; Cölfen, Helmut

2006-10-10

Simple solution analysis of the formation mechanism of complex BaSO(4) fiber bundles in the presence of polyacrylate sodium salt, via a bioinspired approach, is reported. Titration of the polyacrylate solution with Ba(2+) revealed complex formation and the optimum ratio of Ba(2+) to polyacrylate for a slow polymer-controlled mineralization process. This is a much simpler and faster method to determine the appropriate additive/mineral concentration pairs as opposed to more common crystallization experiments in which the additive/mineral concentration is varied. Time-dependent pH measurements were carried out to determine the concentration of solution species from which BaSO(4) supersaturation throughout the fiber formation process can be calculated and the second-order kinetics of the Ba(2+) concentration in solution can be identified. Conductivity measurements, pH measurements, and analytical ultracentrifugation revealed the first formed species to be Ba-polyacrylate complexes. A combination of the solution analysis results and optical microscopic images allows a detailed picture of the complex precipitation and self-organization process, a particle-mediated process involving mesoscopic transformations, to be revealed.

Complex investigation of body and clothing injuries during the identification of the assault instrument.

PubMed

Sitiene, R; Varnaite, J; Zakaras, A

2004-12-02

The value of complex analyses of body injuries and clothing has been proven by practice. The purpose of presented study is to discuss what additional information can be obtained during investigations of clothes in the area of injury. A case study, in which results of visual and stereomicroscopic morphological analysis of wounds, lesions of clothing and their comparison are presented. Examination of wounds revealed that some of them were made by blunt, others--by stabbing instrument. Lesions of clothes were made by secant instrument. Comparison of data enabled to determine characteristics of the instrument with greater precision--it was secant-stabbing tool. An experiment with suspected assault instrument--wheel wrench--under controlled conditions was performed. It was found that the head of this wheel wrench can be fixated when secant blow are performed, and it's sharp edge leaves secant-stabbing wounds. Our study revealed that precise knowledge of the assault circumstances enabled to select suitable conditions for experiment and this in turn enabled to identify the instrument of assault.

Of colored numbers and numbered colors: interactive processes in grapheme-color synesthesia.

PubMed

Gebuis, Titia; Nijboer, Tanja C W; van der Smagt, Maarten J

2009-01-01

Grapheme-color synesthetes experience a specific color when they see a grapheme but they do not report to perceive a grapheme when a color is presented. In this study, we investigate whether color can still evoke number-processes even when a vivid number experience is absent. We used color-number and number-color priming, both revealing faster responses in congruent compared to incongruent conditions. Interestingly, the congruency effect was of similar magnitude for both conditions, and a numerical distance effect was present only in the color-number priming task. In addition, a priming task in which synesthetes had to judge the parity of a colored number revealed faster responses in parity congruent than in parity incongruent trials. These combined results demonstrate that synesthesia is indeed bi-directional and of similar strength in both directions. Furthermore, they illustrate the precise nature of these interactions and show that the direction of these interactions is determined by task demands, not by the more vividly experienced aspect of the stimulus.

Childhood adversity and the continued exposure to trauma and violence among adolescent gang members

PubMed Central

Quinn, Katherine; Pacella, Maria L.; Dickson-Gomez, Julia; Nydegger, Liesl A.

2017-01-01

This study examines experiences of childhood adversity, trauma, and violence among adolescent gang members prior to and during adolescent gang involvement to better understand the effects of violence and trauma on gang members. We conducted 58 qualitative semi-structured interviews with members of six adolescent gangs. Data was analyzed using thematic content analysis and the constant comparative method in MAXQDA. Findings revealed that frequent and ongoing exposure to neighborhood violence and personal and familial trauma led many youth to normalize experiences of violence. Furthermore, although they believed gangs would offer protection and social support, gang membership led to additional exposure to violence and trauma and bleak future expectations. Interventions for adolescent gang members should address the complex childhoods and cumulative traumatic experiences of these adolescents. PMID:28262961

[Meaning of becoming mother and son/daughter through massage].

PubMed

Márquez Doren, Francisca; Lucchini Raies, Camila; Rivera Martínez, Soledad

2014-06-01

Revealing the experience of mothers when massaging their children to know the phenomenon in the context of a mother-child healthy development. This is a qualitative study with a phenomenological approach carried out with 11 women who massaged their children and answered the guiding question: What did the experience of massaging your child mean to you? The experience of massaging their children meant the development of their being a mother and of being a son/daughter, in addition to developing the attachment relationship between them. The massage can operationalize this integrality, become a tool of communication, stimulation and promotion of secure attachment, by promoting the loving interaction between mother and child. This practice should be considered as an option in the programs that promote the comprehensive health of the mother and child.

High-Resolution NMR Reveals Secondary Structure and Folding of Amino Acid Transporter from Outer Chloroplast Membrane

PubMed Central

Zook, James D.; Molugu, Trivikram R.; Jacobsen, Neil E.; Lin, Guangxin; Soll, Jürgen; Cherry, Brian R.; Brown, Michael F.; Fromme, Petra

2013-01-01

Solving high-resolution structures for membrane proteins continues to be a daunting challenge in the structural biology community. In this study we report our high-resolution NMR results for a transmembrane protein, outer envelope protein of molar mass 16 kDa (OEP16), an amino acid transporter from the outer membrane of chloroplasts. Three-dimensional, high-resolution NMR experiments on the 13C, 15N, 2H-triply-labeled protein were used to assign protein backbone resonances and to obtain secondary structure information. The results yield over 95% assignment of N, HN, CO, Cα, and Cβ chemical shifts, which is essential for obtaining a high resolution structure from NMR data. Chemical shift analysis from the assignment data reveals experimental evidence for the first time on the location of the secondary structure elements on a per residue basis. In addition T 1Z and T2 relaxation experiments were performed in order to better understand the protein dynamics. Arginine titration experiments yield an insight into the amino acid residues responsible for protein transporter function. The results provide the necessary basis for high-resolution structural determination of this important plant membrane protein. PMID:24205117

Feature Integration and Task Switching: Diminished Switch Costs after Controlling for Stimulus, Response, and Cue Repetitions

PubMed Central

Schmidt, James R.; Liefooghe, Baptist

2016-01-01

This report presents data from two versions of the task switching procedure in which the separate influence of stimulus repetitions, response key repetitions, conceptual response repetitions, cue repetitions, task repetitions, and congruency are considered. Experiment 1 used a simple alternating runs procedure with parity judgments of digits and consonant/vowel decisions of letters as the two tasks. Results revealed sizable effects of stimulus and response repetitions, and controlling for these effects reduced the switch cost. Experiment 2 was a cued version of the task switch paradigm with parity and magnitude judgments of digits as the two tasks. Results again revealed large effects of stimulus and response repetitions, in addition to cue repetition effects. Controlling for these effects again reduced the switch cost. Congruency did not interact with our novel “unbiased” measure of switch costs. We discuss how the task switch paradigm might be thought of as a more complex version of the feature integration paradigm and propose an episodic learning account of the effect. We further consider to what extent appeals to higher-order control processes might be unnecessary and propose that controls for feature integration biases should be standard practice in task switching experiments. PMID:26964102

Impacts of Visual Sonority and Handshape Markedness on Second Language Learning of American Sign Language

PubMed Central

Newman, Sharlene D.

2016-01-01

The roles of visual sonority and handshape markedness in sign language acquisition and production were investigated. In Experiment 1, learners were taught sign-nonobject correspondences that varied in sign movement sonority and handshape markedness. Results from a sign-picture matching task revealed that high sonority signs were more accurately matched, especially when the sign contained a marked handshape. In Experiment 2, learners produced these familiar signs in addition to novel signs, which differed based on sonority and markedness. Results from a key-release reaction time reproduction task showed that learners tended to produce high sonority signs much more quickly than low sonority signs, especially when the sign contained an unmarked handshape. This effect was only present in familiar signs. Sign production accuracy rates revealed that high sonority signs were more accurate than low sonority signs. Similarly, signs with unmarked handshapes were produced more accurately than those with marked handshapes. Together, results from Experiments 1 and 2 suggested that signs that contain high sonority movements are more easily processed, both perceptually and productively, and handshape markedness plays a differential role in perception and production. PMID:26644551

Fertilization of frog eggs on a Sounding Rocket in space.

PubMed

Ubbels, G A; Berendsen, W; Narraway, J

1989-01-01

During the TEXUS-17 flight (April/May 1988) eggs of a higher organism, the anuran amphibian Xenopus laevis, have for the first time been successfully fertilized under microgravity on a Sounding Rocket. This result also implies that Life Sciences Experiments of Short Duration can be carried out on Sounding Rockets. The latter can therefore function as additional carriers for such experiments. Histological sections of the experimental material demonstrated the penetration of sperm into eggs, while SEM analysis revealed the differentiation of characteristic egg surface structures. Our TEXUS-17 experiment convincingly shows that the modified automatic experiment container, originally designed for experimental BR 52NL on the D1-mission, now functions flawlessly. Eight containers were flown in an airtight, well-isolated box (TEM 06-15), and a similar set was activated on Earth, two hours later. The analysis of the biological material is in progress.

Plasma wave observations during ion gun experiments

NASA Astrophysics Data System (ADS)

Olsen, R. C.; Weddle, L. E.; Roeder, J. L.

1990-06-01

Experiments in charge control on the AF/NASA P78-2 (SCATHA) satellite were conducted with a plasma/ion source in the inner magnetosphere. These experiments were monitored with plasma wave instruments capable of high temporal and frequency resolution in the 0-6 kHz frequency range. Ion gun experiments revealed two distinct classes of behavior. Nonneutralized ion beam operation at 1 mA, 1kV resulted in arcing signatures (spiky in time, broad frequency range), coincident with induced satellite potentials of -600 to -900 V. This signature disappeared when the accelerating voltage was switched off or the beam was neutralized. The signal is attributed to arcing between differentially charged surfaces. An additional feature was noted in the 100-kHz channel of the wave receiver. During emission of dense, low-energy plasma, a signal is generated which may be at the upper hybrid, or plasma frequency for the local plasma.

Ongoing behavioral state information signaled in the lateral habenula guides choice flexibility in freely moving rats

PubMed Central

Baker, Phillip M.; Oh, Sujean E.; Kidder, Kevan S.; Mizumori, Sheri J. Y.

2015-01-01

The lateral habenula (LHb) plays a role in a wide variety of behaviors ranging from maternal care, to sleep, to various forms of cognition. One prominent theory with ample supporting evidence is that the LHb serves to relay basal ganglia and limbic signals about negative outcomes to midbrain monoaminergic systems. This makes it likely that the LHb is critically involved in behavioral flexibility as all of these systems have been shown to contribute when flexible behavior is required. Behavioral flexibility is commonly examined across species and is impaired in various neuropsychiatric conditions including autism, depression, addiction, and schizophrenia; conditions in which the LHb is thought to play a role. Therefore, a thorough examination of the role of the LHb in behavioral flexibility serves multiple functions including understanding possible connections with neuropsychiatric illnesses and additional insight into its role in cognition in general. Here, we assess the LHb’s role in behavioral flexibility through comparisons of the roles its afferent and efferent pathways are known to play. Additionally, we provide new evidence supporting the LHb contributions to behavioral flexibility through organization of specific goal directed actions under cognitively demanding conditions. Specifically, in the first experiment, a majority of neurons recorded from the LHb were found to correlate with velocity on a spatial navigation task and did not change significantly when reward outcomes were manipulated. Additionally, measurements of local field potential (LFP) in the theta band revealed significant changes in power relative to velocity and reward location. In a second set of experiments, inactivation of the LHb with the gamma-aminobutyric acid (GABA) agonists baclofen and muscimol led to an impairment in a spatial/response based repeated probabilistic reversal learning task. Control experiments revealed that this impairment was likely due to the demands of repeated switching behaviors as rats were unimpaired on initial discrimination acquisition or retention of probabilistic learning. Taken together, these novel findings compliment other work discussed supporting a role for the LHb in action selection when cognitive or emotional demands are increased. Finally, we discuss future mechanisms by which a superior understanding of the LHb can be obtained through additional examination of behavioral flexibility tasks. PMID:26582981

A Novel Bacteriophage Targeting Cronobacter sakazakii Is a Potential Biocontrol Agent in Foods

PubMed Central

Lee, Ju-Hoon; Bai, Jaewoo; Shin, Hakdong; Kim, Yeran; Park, Bookyung; Heu, Sunggi

2015-01-01

Cronobacter sakazakii is an important pathogen that causes high mortality in infants. Due to its occasional antibiotic resistance, a bacteriophage approach might be an alternative effective method for the control of this pathogen. To develop a novel biocontrol agent using bacteriophages, the C. sakazakii-infecting phage CR5 was newly isolated and characterized. Interestingly, this phage exhibited efficient and relatively durable host lysis activity. In addition, a specific gene knockout study and subsequent complementation experiment revealed that this phage infected the host strain using the bacterial flagella. The complete genome sequence analysis of phage CR5 showed that its genome contains 223,989 bp of DNA, including 231 predicted open reading frames (ORFs), and it has a G+C content of 50.06%. The annotated ORFs were classified into six functional groups (structure, packaging, host lysis, DNA manipulation, transcription, and additional functions); no gene was found to be related to virulence or toxin or lysogen formation, but >80% of the predicted ORFs are unknown. In addition, a phage proteomic analysis using SDS-PAGE and matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF MS) revealed that seven phage structural proteins are indeed present, supporting the ORF predictions. To verify the potential of this phage as a biocontrol agent against C. sakazakii, it was added to infant formula milk contaminated with a C. sakazakii clinical isolate or food isolate, revealing complete growth inhibition of the isolates by the addition of phage CR5 when the multiplicity of infection (MOI) was 105. PMID:26497465

Investigation of the impact of trace elements on anaerobic volatile fatty acid degradation using a fractional factorial experimental design.

PubMed

Jiang, Ying; Zhang, Yue; Banks, Charles; Heaven, Sonia; Longhurst, Philip

2017-11-15

The requirement of trace elements (TE) in anaerobic digestion process is widely documented. However, little is understood regarding the specific requirement of elements and their critical concentrations under different operating conditions such as substrate characterisation and temperature. In this study, a flask batch trial using fractional factorial design is conducted to investigate volatile fatty acids (VFA) anaerobic degradation rate under the influence of the individual and combined effect of six TEs (Co, Ni, Mo, Se, Fe and W). The experiment inoculated with food waste digestate, spiked with sodium acetate and sodium propionate both to 10 g/l. This is followed by the addition of a selection of the six elements in accordance with a 2 6-2 fractional factorial principle. The experiment is conducted in duplicate and the degradation of VFA is regularly monitored. Factorial effect analysis on the experimental results reveals that within these experimental conditions, Se has a key role in promoting the degradation rates of both acetic and propionic acids; Mo and Co are found to have a modest effect on increasing propionic acid degradation rate. It is also revealed that Ni shows some inhibitory effects on VFA degradation, possibly due to its toxicity. Additionally, regression coefficients for the main and second order effects are calculated to establish regression models for VFA degradation. Copyright © 2017 Elsevier Ltd. All rights reserved.

Beyond bilingualism: multilingual experience correlates with caudate volume.

PubMed

Hervais-Adelman, Alexis; Egorova, Natalia; Golestani, Narly

2018-06-14

The multilingual brain implements mechanisms that serve to select the appropriate language as a function of the communicative environment. Engaging these mechanisms on a regular basis appears to have consequences for brain structure and function. Studies have implicated the caudate nuclei as important nodes in polyglot language control processes, and have also shown structural differences in the caudate nuclei in bilingual compared to monolingual populations. However, the majority of published work has focused on the categorical differences between monolingual and bilingual individuals, and little is known about whether these findings extend to multilingual individuals, who have even greater language control demands. In the present paper, we present an analysis of the volume and morphology of the caudate nuclei, putamen, pallidum and thalami in 75 multilingual individuals who speak three or more languages. Volumetric analyses revealed a significant relationship between multilingual experience and right caudate volume, as well as a marginally significant relationship with left caudate volume. Vertex-wise analyses revealed a significant enlargement of dorsal and anterior portions of the left caudate nucleus, known to have connectivity with executive brain regions, as a function of multilingual expertise. These results suggest that multilingual expertise might exercise a continuous impact on brain structure, and that as additional languages beyond a second are acquired, the additional demands for linguistic and cognitive control result in modifications to brain structures associated with language management processes.

Japanese Experiment Module arrival

NASA Image and Video Library

2007-03-29

Inside the Space Station Processing Facility, the Experiment Logistics Module Pressurized Section for the Japanese Experiment Module is revealed after the top of the crate is removed. The logistics module is one of the components of the Japanese Experiment Module or JEM, also known as Kibo, which means "hope" in Japanese. Kibo comprises six components: two research facilities -- the Pressurized Module and Exposed Facility; a Logistics Module attached to each of them; a Remote Manipulator System; and an Inter-Orbit Communication System unit. Kibo also has a scientific airlock through which experiments are transferred and exposed to the external environment of space. Kibo is Japan's first human space facility and its primary contribution to the station. Kibo will enhance the unique research capabilities of the orbiting complex by providing an additional environment in which astronauts can conduct science experiments. The various components of JEM will be assembled in space over the course of three Space Shuttle missions. The first of those three missions, STS-123, will carry the Experiment Logistics Module Pressurized Section aboard the Space Shuttle Endeavour, targeted for launch in 2007.

Depression and experience of vision loss in group of adults in rehabilitation setting: mixed-methods pilot study.

PubMed

Senra, Hugo; Vieira, Cristina R; Nicholls, Elizabeth G; Leal, Isabel

2013-01-01

There is a paucity of literature regarding the relationship between the experience of vision loss and depression. Therefore, the current pilot study aimed to explore whether significant differences existed in levels of depression between adults with different vision loss experiences. A group of adults aged between 20 and 65 yr old with irreversible vision loss in a rehabilitation setting was interviewed. Semistructured interviews were conducted in order to explore patients' experience of vision loss. The Center for Epidemiologic Studies Depression Scale (CES-D) was used to assess depressive levels; 39.5% (n = 15) of patients met CES-D criteria for depression. In addition, higher levels of depression (p < 0.05) were identified in patients whose interviews revealed greater self-awareness of impairment, inadequate social support, and longer rehabilitation stay. Current findings draw attention to variables such as self-awareness of impairment and perceived social support and suggest that depression following vision loss may be related to patients' emotional experiences of impairment and adjustment processes.

Preschoolers' social and moral judgments of third-party helpers and hinderers align with infants' social evaluations.

PubMed

Van de Vondervoort, Julia W; Hamlin, J Kiley

2017-12-01

Two experiments explored preschoolers' social preferences and moral judgments of prosocial and antisocial others. In Experiment 1, 3- to 5-year-olds (N=74) observed helping and hindering scenarios previously used to explore sociomoral evaluation in preverbal infants. Whereas 3-year-olds in Experiment 1 did not reliably distinguish between the helper and hinderer when reporting social preferences or moral judgments, both 4- and 5-year-olds preferred the helper, judged the helper to be "nicer" than the hinderer, selectively allocated punishment to the hinderer, and were able to justify their punishment allocations. A simplified procedure and the addition of comprehension questions in Experiment 2 (N=24) improved 3-year-olds' performance, suggestive that their performance in Experiment 1 was likely due to processing or memory difficulties rather than an inability to engage in explicit social and moral evaluation. These studies reveal that young children readily interpret helping and hindering scenarios as socially and morally relevant. Copyright © 2017 Elsevier Inc. All rights reserved.

Disentangling the Exposure Experience: The Roles of Community Context and Report-back of Environmental Exposure Data

PubMed Central

Adams, Crystal; Brown, Phil; Morello-Frosch, Rachel; Brody, Julia Green; Rudel, Ruthann; Zota, Ami; Dunagan, Sarah; Tovar, Jessica; Patton, Sharyle

2011-01-01

This article examines participants’ responses to receiving their results in a study of household exposure to endocrine disrupting compounds and other pollutants. We study how the “exposure experience” —the embodied, personal experience and understanding of chronic exposure to environmental pollutants— is shaped by community context and the report-back process itself. In addition, we investigate an activist, collective form of exposure experience. We analyze themes of expectations and learning, trust, and action. The findings reveal that while participants interpret scientific results to affirm lay knowledge of urban industrial toxics, they also absorb new information regarding other pollutant sources. By linking the public understanding of science literature to the illness and exposure experience concepts, this study unravels the complex relationship between lay experience and lay understanding of science. It also shows that to support policy development and/or social change, community-based participatory research efforts must attend to participants’ understanding of science. PMID:21673146

Influence of CaCO3 and SiO2 additives on magnetic properties of M-type Sr ferrites

NASA Astrophysics Data System (ADS)

Huang, Ching-Chien; Jiang, Ai-Hua; Hung, Yung-Hsiung; Liou, Ching-Hsuan; Wang, Yi-Chen; Lee, Chi-Ping; Hung, Tong-Yin; Shaw, Chun-Chung; Kuo, Ming-Feng; Cheng, Chun-Hu

2018-04-01

An experiment was carried out to investigate the influence of CaCO3 and SiO2 additives on the magnetic and physical properties of M-type Sr ferrites by changing experimental parameters such as the additive composition and Ca/Si ratio. Specimens were prepared by conventional ceramic techniques. It was found that the magnetic properties (Br = 4.42 kG, iHc = 3.32 kOe and (BH)max = 4.863 MGOe) were considerably improved upon adding CaCO3 = 1.1% and SiO2 = 0.4 wt% together with Co3O4, and the mechanical properties thereof were acceptable for motor applications. It was revealed that CaCO3 and SiO2 additives led to an upswing in the magnetic properties via the enhancement of uniform grain growth, particle alignment, and the densification of Sr ferrite.

Theoretical and experimental design studies for the Atmospheric General Circulation Experiment

NASA Technical Reports Server (NTRS)

Fowlis, W. W.; Hathaway, D. H.; Miller, T. L.; Roberts, G. O.; Kopecky, K. J.

1985-01-01

The major criterion for the Atmospheric General Circulation Experiment (AGCE) design is that it be possible to realize strong baroclinic instability in the spherical configuration chosen. A configuration was selected in which a hemispherical shell of fluid is subjected to latitudinal temperature gradients on its spherical boundaries and the latitudinal boundaries are insulators. Work in the laboratory with a cylindrical version of this configuration revealed more instabilities than baroclinic instability. Since researchers fully expect these additional instabilities to appear in the spherical configuration also, they decided to continue the laboratory cylindrical annulus studies. Four flow regimes were identified: an axisymmetric Hadley circulation, boundary layer convection, baroclinic waves and deep thermal convection. Regime diagrams were prepared.

Development of a flight software testing methodology

NASA Technical Reports Server (NTRS)

Mccluskey, E. J.; Andrews, D. M.

1985-01-01

The research to develop a testing methodology for flight software is described. An experiment was conducted in using assertions to dynamically test digital flight control software. The experiment showed that 87% of typical errors introduced into the program would be detected by assertions. Detailed analysis of the test data showed that the number of assertions needed to detect those errors could be reduced to a minimal set. The analysis also revealed that the most effective assertions tested program parameters that provided greater indirect (collateral) testing of other parameters. In addition, a prototype watchdog task system was built to evaluate the effectiveness of executing assertions in parallel by using the multitasking features of Ada.

Body image and sexual orientation: The experiences of lesbian and bisexual women.

PubMed

Smith, Marie L; Telford, Elina; Tree, Jeremy J

2017-02-01

Western cultures promote a thin and curvaceous ideal body size that most women find difficult to achieve by healthy measures, resulting in poor body image and increased risk for eating pathology. Research focusing on body image in lesbian and bisexual women has yielded inconsistent results. In total, 11 lesbian and bisexual women were interviewed regarding their experiences with body image. Interpretative phenomenological analysis revealed that these women experienced similar mainstream pressures to conform to a thin body ideal. Furthermore, participants perceived additional pressure to conform to heteronormative standards of beauty since the normalisation of homosexuality and the increase in Lesbian, Gay, Bisexual and Transgender representation in mainstream media.

Assessment of hospice health professionals' knowledge, views, and experience with medical marijuana.

PubMed

Uritsky, Tanya J; McPherson, Mary Lynn; Pradel, Françoise

2011-12-01

The medicinal and recreational use of cannabis has been controversial, especially in the United States. Marijuana for medicinal use is approved in 14 U.S. states and has recently been considered for legalization in several additional states. Given its demonstrated efficacy in symptom management, marijuana has a potential role in palliative care. This study utilized a 16-item questionnaire to assess the knowledge, experience, and views of hospice professionals regarding the use of marijuana in terminally ill patients. The study results revealed that, like the general public, hospice health care providers are generally in favor of legalization of marijuana and, if legalized, would support its use in symptom management for their terminally ill patients.

Decisions reduce sensitivity to subsequent information.

PubMed

Bronfman, Zohar Z; Brezis, Noam; Moran, Rani; Tsetsos, Konstantinos; Donner, Tobias; Usher, Marius

2015-07-07

Behavioural studies over half a century indicate that making categorical choices alters beliefs about the state of the world. People seem biased to confirm previous choices, and to suppress contradicting information. These choice-dependent biases imply a fundamental bound of human rationality. However, it remains unclear whether these effects extend to lower level decisions, and only little is known about the computational mechanisms underlying them. Building on the framework of sequential-sampling models of decision-making, we developed novel psychophysical protocols that enable us to dissect quantitatively how choices affect the way decision-makers accumulate additional noisy evidence. We find robust choice-induced biases in the accumulation of abstract numerical (experiment 1) and low-level perceptual (experiment 2) evidence. These biases deteriorate estimations of the mean value of the numerical sequence (experiment 1) and reduce the likelihood to revise decisions (experiment 2). Computational modelling reveals that choices trigger a reduction of sensitivity to subsequent evidence via multiplicative gain modulation, rather than shifting the decision variable towards the chosen alternative in an additive fashion. Our results thus show that categorical choices alter the evidence accumulation mechanism itself, rather than just its outcome, rendering the decision-maker less sensitive to new information. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

Human functional magnetic resonance imaging reveals separation and integration of shape and motion cues in biological motion processing.

PubMed

Jastorff, Jan; Orban, Guy A

2009-06-03

In a series of human functional magnetic resonance imaging experiments, we systematically manipulated point-light stimuli to identify the contributions of the various areas implicated in biological motion processing (for review, see Giese and Poggio, 2003). The first experiment consisted of a 2 x 2 factorial design with global shape and kinematics as factors. In two additional experiments, we investigated the contributions of local opponent motion, the complexity of the portrayed movement and a one-back task to the activation pattern. Experiment 1 revealed a clear separation between shape and motion processing, resulting in two branches of activation. A ventral region, extending from the lateral occipital sulcus to the posterior inferior temporal gyrus, showed a main effect of shape and its extension into the fusiform gyrus also an interaction. The dorsal region, including the posterior inferior temporal sulcus and the posterior superior temporal sulcus (pSTS), showed a main effect of kinematics together with an interaction. Region of interest analysis identified these interaction sites as the extrastriate and fusiform body areas (EBA and FBA). The local opponent motion cue yielded only little activation, limited to the ventral region (experiment 3). Our results suggest that the EBA and the FBA correspond to the initial stages in visual action analysis, in which the performed action is linked to the body of the actor. Moreover, experiment 2 indicates that the body areas are activated automatically even in the absence of a task, whereas other cortical areas like pSTS or frontal regions depend on the complexity of movements or task instructions for their activation.

Probing the exchange statistics of one-dimensional anyon models

NASA Astrophysics Data System (ADS)

Greschner, Sebastian; Cardarelli, Lorenzo; Santos, Luis

2018-05-01

We propose feasible scenarios for revealing the modified exchange statistics in one-dimensional anyon models in optical lattices based on an extension of the multicolor lattice-depth modulation scheme introduced in [Phys. Rev. A 94, 023615 (2016), 10.1103/PhysRevA.94.023615]. We show that the fast modulation of a two-component fermionic lattice gas in the presence a magnetic field gradient, in combination with additional resonant microwave fields, allows for the quantum simulation of hardcore anyon models with periodic boundary conditions. Such a semisynthetic ring setup allows for realizing an interferometric arrangement sensitive to the anyonic statistics. Moreover, we show as well that simple expansion experiments may reveal the formation of anomalously bound pairs resulting from the anyonic exchange.

Does precision decrease with set size?

PubMed Central

Mazyar, Helga; van den Berg, Ronald; Ma, Wei Ji

2012-01-01

The brain encodes visual information with limited precision. Contradictory evidence exists as to whether the precision with which an item is encoded depends on the number of stimuli in a display (set size). Some studies have found evidence that precision decreases with set size, but others have reported constant precision. These groups of studies differed in two ways. The studies that reported a decrease used displays with heterogeneous stimuli and tasks with a short-term memory component, while the ones that reported constancy used homogeneous stimuli and tasks that did not require short-term memory. To disentangle the effects of heterogeneity and short-memory involvement, we conducted two main experiments. In Experiment 1, stimuli were heterogeneous, and we compared a condition in which target identity was revealed before the stimulus display with one in which it was revealed afterward. In Experiment 2, target identity was fixed, and we compared heterogeneous and homogeneous distractor conditions. In both experiments, we compared an optimal-observer model in which precision is constant with set size with one in which it depends on set size. We found that precision decreases with set size when the distractors are heterogeneous, regardless of whether short-term memory is involved, but not when it is homogeneous. This suggests that heterogeneity, not short-term memory, is the critical factor. In addition, we found that precision exhibits variability across items and trials, which may partly be caused by attentional fluctuations. PMID:22685337

Induction simulation of gas core nuclear engine

NASA Technical Reports Server (NTRS)

Poole, J. W.; Vogel, C. E.

1973-01-01

The design, construction and operation of an induction heated plasma device known as a combined principles simulator is discussed. This device incorporates the major design features of the gas core nuclear rocket engine such as solid feed, propellant seeding, propellant injection through the walls, and a transpiration cooled, choked flow nozzle. Both argon and nitrogen were used as propellant simulating material, and sodium was used for fuel simulating material. In addition, a number of experiments were conducted utilizing depleted uranium as the fuel. The test program revealed that satisfactory operation of this device can be accomplished over a range of operating conditions and provided additional data to confirm the validity of the gas core concept.

The Mystery of the Mars North Polar Gravity-Topography Correlation(Or Lack Thereof)

NASA Technical Reports Server (NTRS)

Phillips, R. J.; Sjogren, W. L.; Johnson, C. L.

1999-01-01

Maps of moderately high resolution gravity data obtained from the Mars Global Surveyor (MGS) gravity calibration orbit campaign and high precision topography obtained from the Mars Orbiter Laser Altimeter (MOLA) experiment reveal relationships between gravity and topography in high northern latitudes of Mars. Figure 1 shows the results of a JPL spherical harmonic gravity model bandpass filtered between degrees 6 and 50 contoured over a MOLA topographic image. A positive gravity anomaly exists over the main North Polar cap, but there are at least six additional positive gravity anomalies, as well as a number of smaller negative anomalies, with no obvious correlation to topography. Additional information is contained in the original extended abstract.

Summation in autoshaping is affected by the similarity of the visual stimuli to the stimulation they replace.

PubMed

Pearce, John M; Redhead, Edward S; George, David N

2002-04-01

Pigeons received autoshaping with 2 stimuli, A and B, presented in adjacent regions on a television screen. Conditioning with each stimulus was therefore accompanied by stimulation that was displaced from the screen whenever the other stimulus was presented. Test trials with AB revealed stronger responding if this displaced stimulation was similar to, rather than different from, A and B. For a further experiment the training just described included trials with A and B accompanied by an additional, similar, stimulus. Responding during test trials with AB was stronger if the additional trials signaled the presence rather than the absence of food. The results are explained with a configural theory of conditioning.

Juror Decision Making in Acquaintance and Marital Rape: The Influence of Clothing, Alcohol, and Preexisting Stereotypical Attitudes.

PubMed

Osborn, Kirsty; Davis, Josh P; Button, Susan; Foster, John

2018-04-01

Stereotypical biases about women's roles in intimate relationships including their marital status and lifestyle choices such as clothing and alcohol use influence juror attributions of rape case defendant guilt, potentially reducing access to justice for victims. Across two mock-juror decision-making experiments, participants read identical fictitious sexual assault vignettes varying in intoxicated defendant-complainant relationship (married vs. acquaintance), accompanied by photographs of complainant clothing at the crime (body revealing vs. plain) and in court (smart vs. casual). Experiment 2 additionally described the defendant's alcohol consumption as either under or over the drink drive limit. Most participants delivered guilty verdicts (Experiment 1: 86.7%; Experiment 2: 75.5%), recommending mean prison sentences of 5.04 years in Experiment 1 ( n = 218 students) and 4.33 years in Experiment 2 ( n = 1,086 members of public). In Experiment 1, guilty verdict rates and sentences were significantly higher when the married-but not the acquaintance-complainant dressed smartly rather than casually in court. In Experiment 2, significantly more guilty verdicts were delivered by females (80.3%) than males (66.9%), while sentence lengths were longer in acquaintance ( M = 4.52 years) than married conditions ( M = 4.10). Significant interactions between defendant alcohol use and clothing choice of the married-but not the acquaintance complainant-at the crime also influenced sentencing decisions. Higher scores on additionally administered scales measuring rape myth acceptance and sexist attitudes, but not alcohol expectancies, predicted lenient sentencing decisions in both experiments. These findings highlight how "rape myths" concerning marriages drive juror decisions. Prosecuting lawyers should use these results to better challenge these attitudes in court. Internationally, rape is often unreported to the police, and married victims may be more willing to come forward if they believe unbiased access to justice is likely.

Tipping Points in Adolescent Adjustment: Predicting Social Functioning from Adolescents’ Conflict with Parents and Friends

PubMed Central

Ehrlich, Katherine B.; Dykas, Matthew J.; Cassidy, Jude

2012-01-01

Despite widespread interest in examining the role of conflict for adolescent development, researchers only rarely have examined adolescents’ experiences of conflict across relationships. The present study examined how adolescents’ experiences of conflict with parents and friends were linked to their social functioning. Adolescents (n = 189) and their mothers and fathers participated in semi-structured discussions about areas of adolescent-parent conflict in the laboratory. In addition, adolescents reported about conflict in their best friendships, and peers reported about adolescents’ social acceptance and behavior in social settings. Parent-adolescent conflict was associated with peer-reported aggression and delinquency, and friendship conflict was associated with delinquency and prosocial behavior. In addition, significant Parent-Adolescent Conflict × Friend-Adolescent Conflict interactions revealed that parent-adolescent conflict was associated with poor social functioning only when conflict with best friends was also high. The findings suggest that consideration of conflict across relationships may yield insight into the specific contexts in which conflict is associated with negative outcomes for adolescents. PMID:22946461

Quantitative analysis of single-molecule superresolution images

PubMed Central

Coltharp, Carla; Yang, Xinxing; Xiao, Jie

2014-01-01

This review highlights the quantitative capabilities of single-molecule localization-based superresolution imaging methods. In addition to revealing fine structural details, the molecule coordinate lists generated by these methods provide the critical ability to quantify the number, clustering, and colocalization of molecules with 10 – 50 nm resolution. Here we describe typical workflows and precautions for quantitative analysis of single-molecule superresolution images. These guidelines include potential pitfalls and essential control experiments, allowing critical assessment and interpretation of superresolution images. PMID:25179006

Experience of Soviet Medicine in a Great Patriotic War 1941-1945. Part 1 (Opyt Soveskoy Meditsimy v Velikoy Otechestvennoy Voyne 1941-1945),

DTIC Science & Technology

1981-04-15

in the kidney. Certain light/world tc the etiology of stone-education can spill the study of structure and chemical composition of the ramoved or...det=ct Ita h !cccccus aureis, it is thinner/less frequent than the ProteIs vu ca!E, which cause alkaline fermentation of urine. DOC = 80116005 PAGE Page...possible to reveal insignificant damages. However, in the additional photograph, made under such conditions, when central light bean is perpendicular

Cultural Stressors and Mental Health Symptoms among Mexican Americans: A Prospective Study Examining the Moderating Roles of the Family and Neighborhood Contexts

PubMed Central

Nair, Rajni L; White, Rebecca. M. B.; Zeiders, Katherine. H.; Roosa, Mark W.

2012-01-01

Studies of stress consistently have linked individuals’ experiences of stress to maladjustment, but limited attention has been given to cultural stressors commonly experienced by minority individuals. To address this, the current study examined the links between cultural stressors and prospective changes in mental health symptoms in a sample of 710 (49% female) Mexican American youth. In addition, the moderating role of both family and neighborhood cohesion was examined. In-home interviews were completed with youth, mothers (required) and fathers (optional) to collect data on youth’s experiences of cultural stressors (discrimination and language hassles) and internalizing/externalizing behavior, and mothers’ report of family cohesion and mothers’ and fathers’ report of neighborhood cohesion. Analyses revealed that youth’s experiences of discrimination and language hassles at 5th grade were related positively to increases in internalizing symptoms at 7th grade. Additionally, youths who reported higher levels of language hassles in 5th grade experienced increases in externalizing symptoms across the 2-year span. Both family and neighborhood cohesion emerged as significant moderating factors but their impact was conditional on youth’s gender and nativity. Limitations and future implications are discussed. PMID:23111841

Cultural stressors and mental health symptoms among Mexican Americans: a prospective study examining the impact of the family and neighborhood context.

PubMed

Nair, Rajni L; White, Rebecca M B; Roosa, Mark W; Zeiders, Katharine H

2013-10-01

Studies of stress consistently have linked individuals' experiences of stress to maladjustment, but limited attention has been given to cultural stressors commonly experienced by minority individuals. To address this, the current study examined the links between cultural stressors and prospective changes in mental health symptoms in a sample of 710 (49 % female) Mexican American youth. In addition, the moderating role of both family and neighborhood cohesion was examined. In-home interviews were completed with youth, mothers (required) and fathers (optional) to collect data on youth's experiences of cultural stressors (discrimination and language hassles) and internalizing/externalizing behavior, and mothers' report of family cohesion and mothers' and fathers' report of neighborhood cohesion. Analyses revealed that youth's experiences of discrimination and language hassles at 5th grade were related positively to increases in internalizing symptoms at 7th grade. Additionally, youths who reported higher levels of language hassles in 5th grade experienced increases in externalizing symptoms across the 2-year span. Both family and neighborhood cohesion emerged as significant moderating factors but their impact was conditional on youth's gender and nativity. Limitations and future implications are discussed.

The Processing of Human Emotional Faces by Pet and Lab Dogs: Evidence for Lateralization and Experience Effects

PubMed Central

Barber, Anjuli L. A.; Randi, Dania; Müller, Corsin A.; Huber, Ludwig

2016-01-01

From all non-human animals dogs are very likely the best decoders of human behavior. In addition to a high sensitivity to human attentive status and to ostensive cues, they are able to distinguish between individual human faces and even between human facial expressions. However, so far little is known about how they process human faces and to what extent this is influenced by experience. Here we present an eye-tracking study with dogs emanating from two different living environments and varying experience with humans: pet and lab dogs. The dogs were shown pictures of familiar and unfamiliar human faces expressing four different emotions. The results, extracted from several different eye-tracking measurements, revealed pronounced differences in the face processing of pet and lab dogs, thus indicating an influence of the amount of exposure to humans. In addition, there was some evidence for the influences of both, the familiarity and the emotional expression of the face, and strong evidence for a left gaze bias. These findings, together with recent evidence for the dog's ability to discriminate human facial expressions, indicate that dogs are sensitive to some emotions expressed in human faces. PMID:27074009

Characterization and Mitigation of ICRF Antenna - Plasma Edge Interaction

NASA Astrophysics Data System (ADS)

Hong, Rongjie; Tynan, George; Wukitch, Steve; Lin, Yijun; Terry, Jim; Chilenski, M.; Golfinopoulos, T.; Hubbard, A.; Mumgaard, R. T.; Perkins, R.; Reinke, M. L.; Alcator C-Mod Team

2017-10-01

Recent experiments reveal that RF-induced potentials (VRF) in the SOL and impurity source at the antenna can be reduced to background levels via optimizing the power ratio between the inner and outer current straps, Pcent /Pout . Experiments indicate the antenna impurity source reduction for the field aligned antenna is due to geometrical alignment rather than electrical symmetry. Additional experiments performed without an optimized Pcent /Pout showed that VRF and the associated convection cells do not influence the impurity penetration or core impurity confinement. These results suggest the core impurity contamination associated with ICRF heating is dominated by an increased impurity source rather than a change in impurity transport. Further, the convective cell strength was expected to scale inversely with B-field. The observed poloidal velocity (measure of convective cell strength), however, decreased less than expected. In addition, the measured maximum VRF increased and penetrated farther into the SOL at higher B-field and plasma current. Results also suggest VRF is strongly influenced by the SOL plasma parameters rather than by RF parameters. Work supported by the U.S. DoE, Office of Science, Office of Fusion Energy Sciences, User Facility Alcator C-Mod under DE-FC02-99ER54512 and DE-SC 0010720.

Authoring experience: the significance and performance of storytelling in Socratic dialogue with rehabilitating cancer patients.

PubMed

Knox, Jeanette Bresson Ladegaard; Svendsen, Mette Nordahl

2015-08-01

This article examines the storytelling aspect in philosophizing with rehabilitating cancer patients in small Socratic dialogue groups (SDG). Recounting an experience to illustrate a philosophical question chosen by the participants is the traditional point of departure for the dialogical exchange. However, narrating is much more than a beginning point or the skeletal framework of events and it deserves more scholarly attention than hitherto given. Storytelling pervades the whole Socratic process and impacts the conceptual analysis in a SDG. In this article we show how the narrative aspect became a rich resource for the compassionate bond between participants and how their stories cultivated the abstract reflection in the group. In addition, the aim of the article is to reveal the different layers in the performance of storytelling, or of authoring experience. By picking, poking and dissecting an experience through a collaborative effort, most participants had their initial experience existentially refined and the chosen concept of which the experience served as an illustration transformed into a moral compass to be used in self-orientation post cancer.

A microcosm approach to evaluate the degradation of tributyltin (TBT) by Aeromonas molluscorum Av27 in estuarine sediments.

PubMed

Cruz, Andreia; Henriques, Isabel; Sousa, Ana C A; Baptista, Inês; Almeida, Adelaide; Takahashi, Shin; Tanabe, Shinsuke; Correia, António; Suzuki, Satoru; Anselmo, Ana Maria; Mendo, Sónia

2014-07-01

Tributyltin (TBT) is a biocide extremely toxic to a wide range of organisms, which has been used for decades in antifouling paints. Despite its global ban in 2008, TBT is still a problem of great concern due to the high levels trapped in sediments. Aeromonas molluscorum Av27 is a TBT degrading bacterium that was isolated from an estuarine system. We investigated the ability and the role of this bacterium on TBT degradation in this estuarine system, using a microcosm approach in order to mimic environmental conditions. The experiment was established and followed for 150 days. Simultaneously, changes in the indigenous bacterial community structure were also investigated. The results revealed a maximum TBT degradation rate of 28% accompanied by the detection of the degradation products over time. Additionally, it was observed that TBT degradation was significantly enhanced by the presence of Av27. In addition a significantly higher TBT degradation occurred when the concentration of Av27 was higher. TBT degradation affected the bacterial community composition as revealed by the changes in the prevalence of Proteobacteria subdivisions, namely the increase of Deltaproteobacteria and the onset of Epsilonproteobacteria. However, the addition of Av27 strain did not affect the dominant phylotypes. Total bacterial number, bacterial biomass productivity, 16S rRNA gene and denaturing gradient gel electrophoresis (DGGE) analyses also indicated alterations on the bacterial community structure over time, with bacteria non-tolerant to pollutants increasing their representativeness, as, for instance, the increase of the number of Alphaproteobacteria clones from 6% in the beginning to 12% at the end of the experiment. The work herein presented confirms the potential of Av27 strain to be used in the decontamination of TBT-polluted environments. Copyright © 2014 Elsevier Inc. All rights reserved.

3D TOCSY-HSQC NMR for metabolic flux analysis using non-uniform sampling

DOE PAGES

Reardon, Patrick N.; Marean-Reardon, Carrie L.; Bukovec, Melanie A.; ...

2016-02-05

13C-Metabolic Flux Analysis ( 13C-MFA) is rapidly being recognized as the authoritative method for determining fluxes through metabolic networks. Site-specific 13C enrichment information obtained using NMR spectroscopy is a valuable input for 13C-MFA experiments. Chemical shift overlaps in the 1D or 2D NMR experiments typically used for 13C-MFA frequently hinder assignment and quantitation of site-specific 13C enrichment. Here we propose the use of a 3D TOCSY-HSQC experiment for 13C-MFA. We employ Non-Uniform Sampling (NUS) to reduce the acquisition time of the experiment to a few hours, making it practical for use in 13C-MFA experiments. Our data show that the NUSmore » experiment is linear and quantitative. Identification of metabolites in complex mixtures, such as a biomass hydrolysate, is simplified by virtue of the 13C chemical shift obtained in the experiment. In addition, the experiment reports 13C-labeling information that reveals the position specific labeling of subsets of isotopomers. As a result, the information provided by this technique will enable more accurate estimation of metabolic fluxes in larger metabolic networks.« less

The Joint Role of Trained, Untrained, and Observed Actions at the Origins of Goal Recognition

PubMed Central

Gerson, Sarah A.; Woodward, Amanda L.

2014-01-01

Recent findings across a variety of domains reveal the benefits of self-produced experience on object exploration, object knowledge, attention, and action perception. The influence of active experience may be particularly important in infancy, when motor development is undergoing great changes. Despite the importance of self-produced experience, we know that infants and young children are eventually able to gain knowledge through purely observational experience. In the current work, three-month-old infants were given experience with object-directed actions in one of three forms and their recognition of the goal of grasping actions was then assessed in a habituation paradigm. All infants were given the chance to manually interact with the toys without assistance (a difficult task for most three-month-olds). Two of the three groups were then given additional experience with object-directed actions, either through active training (in which Velcro mittens helped infants act more efficiently) or observational training. Findings support the conclusion that self-produced experience is uniquely informative for action perception and suggest that individual differences in spontaneous motor activity may interact with observational experience to inform action perception early in life. PMID:24468646

Adverse adolescent relationship histories and young adult health: Cumulative effects of loneliness, low parental support, relationship instability, intimate partner violence and loss

PubMed Central

Adam, Emma K.; Chyu, Laura; Hoyt, Lindsay; Doane, Leah D.; Boisjoly, Johanne; Duncan, Greg; Chase-Lansdale, Lindsay; McDade, Thomas W.

2011-01-01

Purpose To examine the associations between adverse interpersonal relationship histories experienced during adolescence and health in young adulthood in a large, nationally representative sample. Methods Using data from Waves I, II and III of the National Longitudinal Study of Adolescent Health, multiple adverse relationship experiences are examined, including high loneliness, low perceived parental support, frequent transitions in romantic relationships (relationship instability), exposure to intimate partner violence, and loss by death of important relationship figures. These histories are assessed, both individually and in a relationship risk index, as predictors of self-reported general health and depressive symptoms at Wave III (ages 18 to 27), controlling for baseline (Wave I) health and for demographic and health behavior covariates. Results Net of baseline health and covariates, each type of relationship risk (experienced between Wave I and Wave III) was related to either depression or general health at Wave III, with the strongest effects seen for exposure to intimate partner violence. In addition, a cumulative relationship risk index examining the extent to which youth experienced high levels of multiple relationship risk factors revealed that each additional adverse relationship experience increased the odds of reporting poor mental and general health at Wave III, with increases occurring in an additive manner. Conclusions Multiple types of adverse relationship experiences predicted increases in poor general health and depressive symptoms from adolescence to early adulthood. Consistent with a cumulative risk hypothesis, the more types of adverse relationship experiences a youth experienced, the worse their young adult health outcomes. PMID:21856520

The relationship between the experience of stuttering and demographic characteristics of adults who stutter.

PubMed

Freud, Debora; Kichin-Brin, Marina; Ezrati-Vinacour, Ruth; Roziner, Ilan; Amir, Ofer

2017-06-01

This study aims to examine the association between adults' experience of stuttering and their age, gender and marital status, as well as to evaluate the psychometric properties of the Hebrew version of the OASES-A. The Hebrew version of the OASES-A was administered to 91 adults-who-stutter. The validity of the translated version was evaluated using a subset of 43 participants, who also completed three additional instruments: (a) a Perceived Stuttering Severity (PSS) self-rating scale, (b) the Situation Avoidance Behavior Checklist (SABC), (c) the Students Life Satisfaction scale (SLSS). Finally, the correlations between the participants' OASES-A scores and their age, gender and marital status were calculated. A negative correlation was found between the participants' OASES-A impact scores and their age (p<0.01). In addition, married participants exhibited lower OASES-A impact scores compared with unmarried participants (p<0.05). On the other hand, the speakers' gender was not associated with OASES-A impact scores. revealed high internal consistency of the Hebrew OASES-A, and moderate to strong correlations with the additional examined instruments. Finally, results of the Hebrew version of the questionnaire were comparable with those obtained in other languages. Our results indicated that, within our cohort, age and marital status are significantly associated with the personal experience of stuttering, whereas gender is not. In addition, the Hebrew version of the OASES-A is valid and comparable with equivalent versions in other languages. This facilitates the application of the OASES-A in future clinical and research settings. Copyright © 2017 Elsevier Inc. All rights reserved.

The Extraction of 3D Shape from Texture and Shading in the Human Brain

PubMed Central

Georgieva, Svetlana S.; Todd, James T.; Peeters, Ronald

2008-01-01

We used functional magnetic resonance imaging to investigate the human cortical areas involved in processing 3-dimensional (3D) shape from texture (SfT) and shading. The stimuli included monocular images of randomly shaped 3D surfaces and a wide variety of 2-dimensional (2D) controls. The results of both passive and active experiments reveal that the extraction of 3D SfT involves the bilateral caudal inferior temporal gyrus (caudal ITG), lateral occipital sulcus (LOS) and several bilateral sites along the intraparietal sulcus. These areas are largely consistent with those involved in the processing of 3D shape from motion and stereo. The experiments also demonstrate, however, that the analysis of 3D shape from shading is primarily restricted to the caudal ITG areas. Additional results from psychophysical experiments reveal that this difference in neuronal substrate cannot be explained by a difference in strength between the 2 cues. These results underscore the importance of the posterior part of the lateral occipital complex for the extraction of visual 3D shape information from all depth cues, and they suggest strongly that the importance of shading is diminished relative to other cues for the analysis of 3D shape in parietal regions. PMID:18281304

Spatial and identity negative priming in audition: evidence of feature binding in auditory spatial memory.

PubMed

Mayr, Susanne; Buchner, Axel; Möller, Malte; Hauke, Robert

2011-08-01

Two experiments are reported with identical auditory stimulation in three-dimensional space but with different instructions. Participants localized a cued sound (Experiment 1) or identified a sound at a cued location (Experiment 2). A distractor sound at another location had to be ignored. The prime distractor and the probe target sound were manipulated with respect to sound identity (repeated vs. changed) and location (repeated vs. changed). The localization task revealed a symmetric pattern of partial repetition costs: Participants were impaired on trials with identity-location mismatches between the prime distractor and probe target-that is, when either the sound was repeated but not the location or vice versa. The identification task revealed an asymmetric pattern of partial repetition costs: Responding was slowed down when the prime distractor sound was repeated as the probe target, but at another location; identity changes at the same location were not impaired. Additionally, there was evidence of retrieval of incompatible prime responses in the identification task. It is concluded that feature binding of auditory prime distractor information takes place regardless of whether the task is to identify or locate a sound. Instructions determine the kind of identity-location mismatch that is detected. Identity information predominates over location information in auditory memory.

The proximal experience of gratitude

PubMed Central

Layous, Kristin; Sweeny, Kate; Armenta, Christina; Na, Soojung; Choi, Incheol; Lyubomirsky, Sonja

2017-01-01

Although a great deal of research has tested the longitudinal effects of regularly practicing gratitude, much less attention has been paid to the emotional landscape directly following engagement in gratitude exercises. In three studies, we explored the array of discrete emotions people experience after being prompted to express or recall gratitude. In Studies 1 and 2, two different gratitude exercises produced not only greater feelings of gratitude relative to two positive emotion control conditions (i.e., recalling relief), but also higher levels of other socially relevant states like elevation, connectedness, and indebtedness. In a third study, conducted in both the U.S. and S. Korea, we compared a gratitude exercise to another positive emotion elicitation (i.e., recalling a kind act) and to a neutral task, and again found that the gratitude exercise prompted greater gratitude, elevation, indebtedness, and guilt, but no more embarrassment or shame, than the two comparison conditions. Additionally, in all three studies, emodiversity and cluster analyses revealed that gratitude exercises led to the simultaneous experience of both pleasant and unpleasant socially-relevant states. In sum, although it may seem obvious that gratitude exercises would evoke grateful, positive states, a meta-analysis of our three studies revealed that gratitude exercises actually elicit a mixed emotional experience—one that simultaneously leads individuals to feel uplifted and indebted. PMID:28686593

Impacts of Visual Sonority and Handshape Markedness on Second Language Learning of American Sign Language.

PubMed

Williams, Joshua T; Newman, Sharlene D

2016-04-01

The roles of visual sonority and handshape markedness in sign language acquisition and production were investigated. In Experiment 1, learners were taught sign-nonobject correspondences that varied in sign movement sonority and handshape markedness. Results from a sign-picture matching task revealed that high sonority signs were more accurately matched, especially when the sign contained a marked handshape. In Experiment 2, learners produced these familiar signs in addition to novel signs, which differed based on sonority and markedness. Results from a key-release reaction time reproduction task showed that learners tended to produce high sonority signs much more quickly than low sonority signs, especially when the sign contained an unmarked handshape. This effect was only present in familiar signs. Sign production accuracy rates revealed that high sonority signs were more accurate than low sonority signs. Similarly, signs with unmarked handshapes were produced more accurately than those with marked handshapes. Together, results from Experiments 1 and 2 suggested that signs that contain high sonority movements are more easily processed, both perceptually and productively, and handshape markedness plays a differential role in perception and production. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Species coexistence through simultaneous fluctuation-dependent mechanisms.

PubMed

Letten, Andrew D; Dhami, Manpreet K; Ke, Po-Ju; Fukami, Tadashi

2018-06-12

Understanding the origins and maintenance of biodiversity remains one of biology's grand challenges. From theory and observational evidence, we know that variability in environmental conditions through time is likely critical to the coexistence of competing species. Nevertheless, experimental tests of fluctuation-driven coexistence are rare and have typically focused on just one of two potential mechanisms, the temporal storage effect, to the neglect of the theoretically equally plausible mechanism known as relative nonlinearity of competition. We combined experiments and simulations in a system of nectar yeasts to quantify the relative contribution of the two mechanisms to coexistence. Resource competition models parameterized from single-species assays predicted the outcomes of mixed-culture competition experiments with 83% accuracy. Model simulations revealed that both mechanisms have measurable effects on coexistence and that relative nonlinearity can be equal or greater in magnitude to the temporal storage effect. In addition, we show that their effect on coexistence can be both antagonistic and complementary. These results falsify the common assumption that relative nonlinearity is of negligible importance, and in doing so reveal the importance of testing coexistence mechanisms in combination.

Decoding visual object categories in early somatosensory cortex.

PubMed

Smith, Fraser W; Goodale, Melvyn A

2015-04-01

Neurons, even in the earliest sensory areas of cortex, are subject to a great deal of contextual influence from both within and across modality connections. In the present work, we investigated whether the earliest regions of somatosensory cortex (S1 and S2) would contain content-specific information about visual object categories. We reasoned that this might be possible due to the associations formed through experience that link different sensory aspects of a given object. Participants were presented with visual images of different object categories in 2 fMRI experiments. Multivariate pattern analysis revealed reliable decoding of familiar visual object category in bilateral S1 (i.e., postcentral gyri) and right S2. We further show that this decoding is observed for familiar but not unfamiliar visual objects in S1. In addition, whole-brain searchlight decoding analyses revealed several areas in the parietal lobe that could mediate the observed context effects between vision and somatosensation. These results demonstrate that even the first cortical stages of somatosensory processing carry information about the category of visually presented familiar objects. © The Author 2013. Published by Oxford University Press.

Decoding Visual Object Categories in Early Somatosensory Cortex

PubMed Central

Smith, Fraser W.; Goodale, Melvyn A.

2015-01-01

Neurons, even in the earliest sensory areas of cortex, are subject to a great deal of contextual influence from both within and across modality connections. In the present work, we investigated whether the earliest regions of somatosensory cortex (S1 and S2) would contain content-specific information about visual object categories. We reasoned that this might be possible due to the associations formed through experience that link different sensory aspects of a given object. Participants were presented with visual images of different object categories in 2 fMRI experiments. Multivariate pattern analysis revealed reliable decoding of familiar visual object category in bilateral S1 (i.e., postcentral gyri) and right S2. We further show that this decoding is observed for familiar but not unfamiliar visual objects in S1. In addition, whole-brain searchlight decoding analyses revealed several areas in the parietal lobe that could mediate the observed context effects between vision and somatosensation. These results demonstrate that even the first cortical stages of somatosensory processing carry information about the category of visually presented familiar objects. PMID:24122136

Primary teachers' subject matter knowledge: decimals

NASA Astrophysics Data System (ADS)

Ubuz, Behiye; Yayan, Betül

2010-09-01

The main objective of this study was to investigate primary teachers' subject matter knowledge in the domain of decimals and more elaborately to investigate their performance and difficulties in reading scale, ordering numbers, finding the nearest decimal and doing operations, such as addition and subtraction. The difficulties in these particular areas are analysed and suggestions are made regarding their causes. Further, factors that influence this knowledge were explored. The sample of the study was 63 primary teachers. A decimal concepts test including 18 tasks was administered and the total scores for the 63 primary teachers ranged from 3 to 18 with a mean and median of 12. Fifty per cent of the teachers were above the mean score. The detailed investigation of the responses revealed that the primary teachers faced similar difficulties that students and pre-service teachers faced. Discrepancy on teachers' knowledge revealed important differences based on educational level attained, but not the number of years of teaching experience and experience in teaching decimals. Some suggestions have been made regarding the implications for pre- and in-service teacher training.

Percutaneous closure of a post-traumatic ventricular septal defect with a patent ductus arteriosus occluder.

PubMed

Xi, Er-Ping; Zhu, Jian; Zhu, Shui-Bo; Yin, Gui-Lin; Liu, Yong; Dong, Yong-Qiang; Zhang, Yu; Xia, Feng

2012-11-01

Ventricular septal defects resulting from post-traumatic cardiac injury are very rare. Percutaneous closure has emerged as a method for treating this disorder. We wish to report our experience in three patients who underwent percutaneous closure of a post-traumatic ventricular septal defect with a patent ductus arteriosus occluder. We treated three patients with post-traumatic ventricular septal defects caused by stab wounds with knives. After the heart wound was repaired, patient examinations revealed ventricular septal defects with pulmonary/systemic flow ratios (Qp/Qs) of over 1.7. The post-traumatic ventricular septal defects were closed percutaneously with a patent ductus arteriosus occluder (Lifetech Scientific (Shenzhen) Co., LTD, Guangdong, China) utilizing standard techniques. Post-operative transthoracic echocardiography revealed no residual left-to-right shunt and indicated normal ventricular function. In addition, 320-slice computerized tomography showed that the occluder was well placed and exhibited normal morphology. Our experiences indicate that closure of a post-traumatic ventricular septal defect using a patent ductus arteriosus occluder is feasible, safe, and effective.

Percutaneous closure of a post-traumatic ventricular septal defect with a patent ductus arteriosus occluder

PubMed Central

Xi, Er-Ping; Zhu, Jian; Zhu, Shui-Bo; Yin, Gui-Lin; Liu, Yong; Dong, Yong-Qiang; Zhang, Yu; Xia, Feng

2012-01-01

OBJECTIVE: Ventricular septal defects resulting from post-traumatic cardiac injury are very rare. Percutaneous closure has emerged as a method for treating this disorder. We wish to report our experience in three patients who underwent percutaneous closure of a post-traumatic ventricular septal defect with a patent ductus arteriosus occluder. METHODS: We treated three patients with post-traumatic ventricular septal defects caused by stab wounds with knives. After the heart wound was repaired, patient examinations revealed ventricular septal defects with pulmonary/systemic flow ratios (Qp/Qs) of over 1.7. The post-traumatic ventricular septal defects were closed percutaneously with a patent ductus arteriosus occluder (Lifetech Scientific (Shenzhen) Co., LTD, Guangdong, China) utilizing standard techniques. RESULTS: Post-operative transthoracic echocardiography revealed no residual left-to-right shunt and indicated normal ventricular function. In addition, 320-slice computerized tomography showed that the occluder was well placed and exhibited normal morphology. CONCLUSION: Our experiences indicate that closure of a post-traumatic ventricular septal defect using a patent ductus arteriosus occluder is feasible, safe, and effective. PMID:23184204

Examination of the teaching styles of nursing professional development specialists, part II: correlational study on teaching styles and use of adult learning theory.

PubMed

Curran, Mary K

2014-08-01

This article, the second in a two-part series, details a correlational study that examined the effects of four variables (graduate degrees in nursing education, professional development training in adult learning theory, nursing professional development [NPD] certification, and NPD specialist experience) on the use of adult learning theory to guide curriculum development. Using the Principles of Adult Learning Scale, 114 NPD specialists tested the hypothesis that NPD specialists with graduate degrees in nursing education, professional development training in adult learning theory, NPD certification, and NPD experience would use higher levels of adult learning theory in their teaching practices to guide curriculum development than those without these attributes. This hypothesis was rejected as regression analysis revealed only one statistically significant predictor variable, NPD certification, influenced the use of adult learning theory. In addition, analysis revealed NPD specialists tended to support a teacher-centered rather than a learner-centered teaching style, indicating NPD educators are not using adult learning theory to guide teaching practices and curriculum development.

Childhood Misfortune, Personality, and Heart Attack: Does Personality Mediate Risk of Myocardial Infarction?

PubMed

Morton, Patricia M; Turiano, Nicholas A; Mroczek, Daniel K; Ferraro, Kenneth F

2016-03-12

Previous research has revealed a link between childhood experiences and adult health, but the mechanisms underlying this relationship are less clear. To elucidate this relationship, we investigated the pathway from childhood misfortune to nonfatal myocardial infarction (MI) via individual differences in personality. Longitudinal data were drawn from the National Survey of Midlife Development in the United States, which sampled 3,032 men and women aged 25-74 years at baseline. Big 5 personality traits and multiple measures of childhood misfortune were used to assess whether personality mediated the effect of childhood misfortune on MI risk. A series of proportional hazards models revealed that neuroticism mediated the effect of additive childhood misfortune on adult MI risk. Childhood misfortune may be formative in the development of personality, which, subsequently, can be consequential to health. These findings highlight the salient roles of early-life experiences and personality to shape health and aging. © The Author 2016. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

The silver lining of a mind in the clouds: interesting musings are associated with positive mood while mind-wandering

PubMed Central

Franklin, Michael S.; Mrazek, Michael D.; Anderson, Craig L.; Smallwood, Jonathan; Kingstone, Alan; Schooler, Jonathan W.

2013-01-01

The negative effects of mind-wandering on performance and mood have been widely documented. In a recent well-cited study, Killingsworth and Gilbert (2010) conducted a large experience sampling study revealing that all off-task episodes, regardless of content, have equal to or lower happiness ratings, than on-task episodes. We present data from a similarly implemented experience sampling study with additional mind-wandering content categories. Our results largely conform to those of the Killingsworth and Gilbert (2010) study, with mind-wandering generally being associated with a more negative mood. However, subsequent analyses reveal situations in which a more positive mood is reported after being off-task. Specifically when off-task episodes are rated for interest, the high interest episodes are associated with an increase in positive mood compared to all on-task episodes. These findings both identify a situation in which mind-wandering may have positive effects on mood, and suggest the possible benefits of encouraging individuals to shift their off-task musings to the topics they find most engaging. PMID:24009599

Dynamics of psychological crisis experience with psychological consulting by gestalt therapy methods.

PubMed

Fahrutdinova, Liliya Raifovna; Nugmanova, Dzhamilia Renatovna

2015-01-01

Dynamics of experience as such and its corporeal, emotional and cognitive elements in the situation of psychological consulting provisioning is covered. The aim of research was to study psychological crisis experience dynamics in the situation when psychological consulting by gestalt therapy methods is provided. Theoretical analysis of the problem of crisis situations, phenomenon and structural, and dynamic organization of experience of the subject of consulting have been carried out. To fulfill research project test subjects experience crisis situation have been selected, studied in the situation when they provided psychological consulting by methods of gestalt therapy, and methodology of study of crisis situations experience has been prepared. Specifics of psychological crisis experience have been revealed and its elements in different stages of psychological consulting by gestalt therapy methods. Dynamics of experience of psychological crisis and its structural elements have been revealed and reliable changes in it have been revealed. Dynamics of psychological crisis experience and its structural elements have been revealed and reliable changes in it have been revealed. "Desiccation" of experience is being observed, releasing its substantiality of negative impression to the end of consulting and development of the new experience of control over crisis situation. Interrelations of structural elements of experience in the process of psychological consulting have been shown. Effecting one structure causes reliable changes in all others structural elements of experience. Giving actual psychological help to clients in crisis situation by methods of gestalt therapy is possible as it was shown in psychological consulting sessions. Structure of client's request has been revealed - problems of personal sense are fixed as the most frequent cause of clients' applications, as well as absence of choices, obtrusiveness of negative thoughts, tend to getting stuck on events took place in the past, drawing into oneself, etc.

SUMO Micrometeorology

DOE Data Explorer

Sevanto, Sanna [Los Alamos National Laboratory; Dickman, Turin L. [Los Alamos National Laboratory; Collins, Adam [Los Alamos National Laboratory; Grossiord, Charlotte [Swiss Federal Institute for Forest Snow and Landscape Research; Adams, Henry [Oklahoma State University; Borrego, Isaac [USGS Southwest Biological Science Center; McDowell, Nate [Pacific Northwest National Laboratory (PNNL); Powers, Heath [Los Alamos National Laboratory; Stockton, Elizabeth [University of New Mexico; Ryan, Max [Los Alamos National Laboratory; Slentz, Matthew [Mohle Adams; Briggs, Sam [Fossil Creek Nursery; McBranch, Natalie [Los Alamos National Laboratory; Morgan, Bryn [Los Alamos National Laboratory

2018-01-01

The Los Alamos Survival–Mortality experiment (SUMO) is located on Frijoles Mesa near Los Alamos, New Mexico, USA, at an elevation of 2150 m. This was a tree manipulation study that investigated the relative impacts of drought and warming on plant function and reveals how trees adapt to drought and heat in semi-arid regions. The study factored the role of tree hydraulic acclimation to both precipitation and temperature and separated their effects.The experiment is located in a pinon-juniper woodland near the ponderosa pine (Pinus ponderosa) forest ecotone. Daily average ambient micrometeorological conditions at the SUMO site. See SUMO Target Tree Information data package (doi:10.15485/1440544) for additional information. Data released by Los Alamos National Lab for public use under LA-UR-18-23656.

SUMO Leaf Water Potential

DOE Data Explorer

Sevanto, Sanna [Los Alamos National Laboratory; Dickman, Turin L. [Los Alamos National Laboratory; Collins, Adam [Los Alamos National Laboratory; Grossiord, Charlotte [Swiss Federal Institute for Forest Snow and Landscape Research; Adams, Henry [Oklahoma State University; Borrego, Isaac [USGS Southwest Biological Science Center; McDowell, Nate [Pacific Northwest National Laboratory (PNNL)

2018-01-01

The Los Alamos Survival–Mortality experiment (SUMO) is located on Frijoles Mesa near Los Alamos, New Mexico, USA, at an elevation of 2150 m. This was a tree manipulation study that investigated the relative impacts of drought and warming on plant function and reveals how trees adapt to drought and heat in semi-arid regions. The study factored the role of tree hydraulic acclimation to both precipitation and temperature and separated their effects.The experiment is located in a pinon-juniper woodland near the ponderosa pine (Pinus ponderosa) forest ecotone. Monthly pre-dawn and midday shoot water potentials for each target tree. See SUMO Target Tree Information data package (doi:10.15485/1440544) for additional information. Data released by Los Alamos National Lab for public use under LA-UR-18-23656.

SUMO Maximum Assimilation

DOE Data Explorer

Sevanto, Sanna [Los Alamos National Laboratory; Dickman, Turin L. [Los Alamos National Laboratory; Collins, Adam [Los Alamos National Laboratory; Grossiord, Charlotte [Swiss Federal Institute for Forest Snow and Landscape Research; Adams, Henry [Oklahoma State University; Borrego, Isaac [USGS Southwest Biological Science Center; McDowell, Nate [Pacific Northwest National Laboratory (PNNL); Powers, Heath [Los Alamos National Laboratory; Stockton, Elizabeth [University of New Mexico; Ryan, Max [Los Alamos National Laboratory; Slentz, Matthew [Mohle Adams; Briggs, Sam [Fossil Creek Nursery; McBranch, Natalie [Los Alamos National Laboratory; Morgan, Bryn [Los Alamos National Laboratory

2018-01-01

The Los Alamos Survival–Mortality experiment (SUMO) is located on Frijoles Mesa near Los Alamos, New Mexico, USA, at an elevation of 2150 m. This was a tree manipulation study that investigated the relative impacts of drought and warming on plant function and reveals how trees adapt to drought and heat in semi-arid regions. The study factored the role of tree hydraulic acclimation to both precipitation and temperature and separated their effects.The experiment is located in a pinon-juniper woodland near the ponderosa pine (Pinus ponderosa) forest ecotone. Maximum assimilation rate measured monthly for each target tree. See SUMO Target Tree Information data package (doi:10.15485/1440544) for additional information. Data released by Los Alamos National Lab for public use under LA-UR-18-23656.

FACE computer simulation. [Flexible Arm Controls Experiment

NASA Technical Reports Server (NTRS)

Sadeh, Willy Z.; Szmyd, Jeffrey A.

1990-01-01

A computer simulation of the FACE (Flexible Arm Controls Experiment) was conducted to assess its design for use in the Space Shuttle. The FACE is supposed to be a 14-ft long articulate structure with 4 degrees of freedom, consisting of shoulder pitch and yaw, elbow pitch, and wrist pitch. Kinematics of the FACE was simulated to obtain data on arm operation, function, workspace and interaction. Payload capture ability was modeled. The simulation indicates the capability for detailed kinematic simulation and payload capture ability analysis, and the feasibility of real-time simulation was determined. In addition, the potential for interactive real-time training through integration of the simulation with various interface controllers was revealed. At this stage, the flexibility of the arm was not yet considered.

Answering Gauguin’s Questions: Where Are We Coming From, Where Are We Going, and What Are We?

ScienceCinema

Ellis, John [CERN

2017-12-09

The knowledge of matter revealed by the current reigning theory of particle physics, the so-called Standard Model, still leaves open many basic questions. What is the origin of the matter in the Universe? How does its mass originate? What is the nature of the dark matter that fills the Universe? Are there additional dimensions of space? The Large Hadron Collider (LHC) at the CERN Laboratory in Geneva, Switzerland, where high-energy experiments have now started, will take physics into a new realm of energy and time, and will address these physics analogues of Gauguin's questions. The answers will set the stage for possible future experiments beyond the scope of the LHC.

Airborne detection of oceanic turbidity cell structure using depth-resolved laser-induced water Raman backscatter

NASA Technical Reports Server (NTRS)

Hoge, F. E.; Swift, R. N.

1983-01-01

Airborne laser-induced, depth-resolved water Raman backscatter is useful in the detection and mapping of water optical transmission variations. This test, together with other field experiments, has identified the need for additional field experiments to resolve the degree of the contribution to the depth-resolved, Raman-backscattered signal waveform that is due to (1) sea surface height or elevation probability density; (2) off-nadir laser beam angle relative to the mean sea surface; and (3) the Gelbstoff fluorescence background, and the analytical techniques required to remove it. When converted to along-track profiles, the waveforms obtained reveal cells of a decreased Raman backscatter superimposed on an overall trend of monotonically decreasing water column optical transmission.

Implications of Cognitive Load for Hypothesis Generation and Probability Judgment

PubMed Central

Sprenger, Amber M.; Dougherty, Michael R.; Atkins, Sharona M.; Franco-Watkins, Ana M.; Thomas, Rick P.; Lange, Nicholas; Abbs, Brandon

2011-01-01

We tested the predictions of HyGene (Thomas et al., 2008) that both divided attention at encoding and judgment should affect the degree to which participants’ probability judgments violate the principle of additivity. In two experiments, we showed that divided attention during judgment leads to an increase in subadditivity, suggesting that the comparison process for probability judgments is capacity limited. Contrary to the predictions of HyGene, a third experiment revealed that divided attention during encoding leads to an increase in later probability judgment made under full attention. The effect of divided attention during encoding on judgment was completely mediated by the number of hypotheses participants generated, indicating that limitations in both encoding and recall can cascade into biases in judgments. PMID:21734897

Parent Discrimination Predicts Mexican-American Adolescent Psychological Adjustment One Year Later

PubMed Central

Gonzales, Nancy A.; Fuligni, Andrew J.

2016-01-01

This study examined whether Mexican-American parent’s experiences with discrimination are related to adolescent psychological adjustment over time. The extent to which associations between parent discrimination and adolescent adjustment vary as a function of parent’s ethnic socialization of their children was also examined. Participants included 344 high school students from Mexican or Mexican-American backgrounds (primarily second generation; ages 14 – 16 at Wave 1) and their primary caregivers who completed surveys in a two-year longitudinal study. Results revealed that parent discrimination predicted internalizing symptoms and self-esteem among adolescents, one year later. Additionally, adolescents were more likely to report low self-esteem in relation to parents’ increased experiences of discrimination when parents conveyed ethnic socialization messages to them. PMID:27224903

Expression and regulation of the neutral amino acid transporter B0AT1 in rat small intestine

PubMed Central

Jando, Julia; Camargo, Simone M. R.; Herzog, Brigitte

2017-01-01

Absorption of neutral amino acids across the luminal membrane of intestinal enterocytes is mediated by the broad neutral amino acid transporter B0AT1 (SLC6A19). Its intestinal expression depends on co-expression of the membrane-anchored peptidase angiotensin converting enzyme 2 (ACE2) and is additionally enhanced by aminopeptidase N (CD13). We investigated in this study the expression of B0AT1 and its auxiliary peptidases as well as its transport function along the rat small intestine. Additionally, we tested its possible short- and long-term regulation by dietary proteins and amino acids. We showed by immunofluorescence that B0AT1, ACE2 and CD13 co-localize on the luminal membrane of small intestinal villi and by Western blotting that their protein expression increases in distal direction. Furthermore, we observed an elevated transport activity of the neutral amino acid L-isoleucine during the nocturnal active phase compared to the inactive one. Gastric emptying was delayed by intragastric application of an amino acid cocktail but we observed no acute dietary regulation of B0AT1 protein expression and L-isoleucine transport. Investigation of the chronic dietary regulation of B0AT1, ACE2 and CD13 by different diets revealed an increased B0AT1 protein expression under amino acid-supplemented diet in the proximal section but not in the distal one and for ACE2 protein expression a reverse localization of the effect. Dietary regulation for CD13 protein expression was not as distinct as for the two other proteins. Ring uptake experiments showed a tendency for increased L-isoleucine uptake under amino acid-supplemented diet and in vivo L-isoleucine absorption was more efficient under high protein and amino acid-supplemented diet. Additionally, plasma levels of branched-chain amino acids were elevated under high protein and amino acid diet. Taken together, our experiments did not reveal an acute amino acid-induced regulation of B0AT1 but revealed a chronic dietary adaptation mainly restricted to the proximal segment of the small intestine. PMID:28915252

Self-subjugation among women: exposure to sexist ideology, self-objectification, and the protective function of the need to avoid closure.

PubMed

Calogero, Rachel M; Jost, John T

2011-02-01

Despite extensive evidence confirming the negative consequences of self-objectification, direct experimental evidence concerning its environmental antecedents is scarce. Incidental exposure to sexist cues was employed in 3 experiments to investigate its effect on self-objectification variables. Consistent with system justification theory, exposure to benevolent and complementary forms of sexism, but not hostile or no sexism, increased state self-objectification, self-surveillance, and body shame among women but not men in Experiment 1. In Experiment 2, we replicated these effects and demonstrated that they are specific to self-objectification and not due to a more general self-focus. In addition, following exposure to benevolent sexism only, women planned more future behaviors pertaining to appearance management than did men; this effect was mediated by self-surveillance and body shame. Experiment 3 revealed that the need to avoid closure might afford women some protection against self-objectification in the context of sexist ideology. (PsycINFO Database Record (c) 2010 APA, all rights reserved).

Yoga Therapy for the Mind Eight-Week Course: Participants׳ Experiences.

PubMed

Kahya, Holly Hannah; Raspin, Courtney Grant

Mindfulness-based therapies are becoming increasingly common in the treatment of mental health conditions. While the popularity of yoga continues to rise in Western culture, little has been done to explore the psychological benefits of yoga from a qualitative, clinical perspective. This study explores participant experiences of the "Yoga Therapy for the Mind Eight-Week Course" (YTFTM), an international, manualized yoga and mindfulness-based intervention for depression and anxiety. Eight female participants took part in semi-structured interviews, and transcripts were analyzed using an interpretative phenomenological analysis, with four master themes emerging: "Personal Journey of Change," "Ambivalence," "Mind/Body Connection," and "Group Experience." The findings highlight potential challenges of yoga and mindfulness-based interventions and the importance of providing adequate support in overcoming these. Findings also reveal that participants experience psychological benefits from the practice of yoga asana in addition to mindfulness, such as a more holistic understanding of psychological distress, adaptive coping strategies, and enhanced well-being. Copyright © 2017 Elsevier Inc. All rights reserved.

Complexity, Training Paradigm Design, and the Contribution of Memory Subsystems to Grammar Learning

PubMed Central

Ettlinger, Marc; Wong, Patrick C. M.

2016-01-01

Although there is variability in nonnative grammar learning outcomes, the contributions of training paradigm design and memory subsystems are not well understood. To examine this, we presented learners with an artificial grammar that formed words via simple and complex morphophonological rules. Across three experiments, we manipulated training paradigm design and measured subjects' declarative, procedural, and working memory subsystems. Experiment 1 demonstrated that passive, exposure-based training boosted learning of both simple and complex grammatical rules, relative to no training. Additionally, procedural memory correlated with simple rule learning, whereas declarative memory correlated with complex rule learning. Experiment 2 showed that presenting corrective feedback during the test phase did not improve learning. Experiment 3 revealed that structuring the order of training so that subjects are first exposed to the simple rule and then the complex improved learning. The cumulative findings shed light on the contributions of grammatical complexity, training paradigm design, and domain-general memory subsystems in determining grammar learning success. PMID:27391085

Attentional load and implicit sequence learning.

PubMed

Shanks, David R; Rowland, Lee A; Ranger, Mandeep S

2005-06-01

A widely employed conceptualization of implicit learning hypothesizes that it makes minimal demands on attentional resources. This conjecture was investigated by comparing learning under single-task and dual-task conditions in the sequential reaction time (SRT) task. Participants learned probabilistic sequences, with dual-task participants additionally having to perform a counting task using stimuli that were targets in the SRT display. Both groups were then tested for sequence knowledge under single-task (Experiments 1 and 2) or dual-task (Experiment 3) conditions. Participants also completed a free generation task (Experiments 2 and 3) under inclusion or exclusion conditions to determine if sequence knowledge was conscious or unconscious in terms of its access to intentional control. The experiments revealed that the secondary task impaired sequence learning and that sequence knowledge was consciously accessible. These findings disconfirm both the notion that implicit learning is able to proceed normally under conditions of divided attention, and that the acquired knowledge is inaccessible to consciousness. A unitary framework for conceptualizing implicit and explicit learning is proposed.

Relatively brief environmental enrichment aids recovery of learning capacity and alters brain measures after postweaning brain lesions in rats

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

Will, B.E.; Rosenzweig, M.R.; Bennett, E.L.

1977-01-01

Enriched postlesion experience aided in overcoming effects of simultaneous bilateral cerebral lesions made at 30 days of age in one experiment with inbred Fischer rats and in a second experiment with the Berkeley S/sub 1/ strain. The lesions were directed to the occipital cortex, but in most cases there was also some impairment of the hippocampus. For 60 days after operations, half of the rats lived in small individual cages and half lived in groups in large enriched-environment cages. They were then pretrained and tested on the standard 12 Hebb-Williams problems. Daily injections of methamphetamine (vs. saline) during the periodmore » of differential experience in the first experiment produced no effect on the behavioral scores. The second experiment included groups that received only 2 hr/day of enriched experience, and they benefited as much as groups that remained in the enriched environment 24 hr/day. The results of both experiments demonstrated significant beneficial effects of environment when bilateral lesions were made at a later age and when the periods of enriched experience were shorter than had previously been tested. Two additional experiments revealed significant effects of both lesions and environment on weight and RNA/DNA of brain regions.« less

Meaning reconstruction in the face of terror: An examination of recovery and posttraumatic growth among victims of the 9/11 World Trade Center attacks.

PubMed

Richardson, Katherine M

2015-01-01

This study examines the relationship between meaning reconstruction with posttraumatic growth and depreciation in the aftermath of terrorist trauma and loss. A group of individuals (n=118) who were personally affected by the September 11, 2001 terrorist attacks were surveyed about their experiences and administered the Posttraumatic Growth Inventory and Impact of Event scales. Subjects were volunteer docents at the Tribute World Trade Center Visitor Center. Results revealed that ability to make sense of one's 9/11 experience was related to recovery but not to posttraumatic growth, whereas ability to find some benefit in the experience was related to growth. In addition, location in downtown Manhattan on September 11, 2001 was related to higher levels of posttraumatic depreciation. Findings suggest that two aspects of meaning reconstruction are differentially related to recovery and posttraumatic growth.

Coming Out Experiences of Hispanic Sexual Minority Young Adults in South Florida.

PubMed

Gattamorta, Karina; Quidley-Rodriguez, Narciso

2017-08-03

Sexual minority youth and young adults (SMYYA) have higher prevalence of mental and behavioral health problems potentially linked to experiences of discrimination, stigma, and rejection. Among Hispanics, the intersection of stressors related to being an ethnic and sexual minority may result in compounding adverse outcomes. Coming out may play an important role in experiencing discrimination, stigma, and rejection. However, limited research examines coming out among Hispanic SMYYA (HSMYYA). This qualitative study seeks to understand the coming-out experiences of HSMYYA living in South Florida. Twenty participants between 18 and 28 years old were interviewed. Qualitative content analysis generated codes, which were grouped into categories to generate themes. This study presents data highlighting reasons for disclosing and not disclosing sexual orientation and the perceived consequences of those decisions. Additionally, we discuss unique cultural elements that impact HSMYYA's decisions to reveal sexual orientation.

Immersion in the virtual environment: the effect of a musical score on the video gaming experience.

PubMed

Lipscomb, Scott D; Zehnder, Sean M

2004-11-01

This study provides one of very few experimental investigations into the impact of a musical soundtrack on the video gaming experience. Participants were randomly assigned to one of three experimental conditions: game-with-music, game-without-music, or music-only. After playing each of three segments of The Lord of the Rings: The Two Towers (Electronic Arts, 2002)--or, in the music-only condition, listening to the musical score that accompanies the scene--subjects responded on 21 verbal scales. Results revealed that some, but not all, of the verbal scales exhibited a statistically significant difference due to the presence of a musical score. In addition, both gender and age level were shown to be significant factors for some, but not all, of the verbal scales. Details of the specific ways in which music affects the gaming experience are provided in the body of the paper.

The role of similarity cues in the development of trust in sources of information about GM food.

PubMed

Meijnders, Anneloes; Midden, Cees; Olofsson, Anna; Ohman, Susanna; Matthes, Jörg; Bondarenko, Olha; Gutteling, Jan; Rusanen, Maria

2009-08-01

In evaluating complex new technologies, people are usually dependent on information provided by others, for example, experts or journalists, and have to determine whether they can trust these information sources. This article focuses on similarity as the basis for trust. The first experiment (N = 261) confirmed that a journalist writing about genetically modified (GM) food was trusted more when his attitude was congruent with that of his readers. In addition, the experiment showed that this effect was mediated by the perceived similarity of the journalist. The second experiment (N = 172) revealed that trust in a journalist writing about the focal domain of GM food was even influenced by him expressing a congruent attitude in an unrelated domain. This result supports a general similarity account of the congruence effect on trust, as opposed to a confirmatory bias account.

[Considering body ethics in the healthcare profession].

PubMed

Wang, Shin-Yun

2014-10-01

This article uses the theory of body phenomenology and Watson's caring theory to develop and apply body ethics to the clinical healthcare profession. This attempt is meant to facilitate deep, humanistic experiences for healthcare personnel. The analysis of body phenomenology reveals that the soul is banished from her familiar and comfortable "at-home" status when illness and pain invade the body. In such situations, the body becomes an external object that is self-alienated. This experience induces experiences such as solitude and violence. However, it also holds the potential to expose the original morality of the body. Additionally, this article discusses popular tools used in clinical ethics such as principalism and virtual-based ethics, which are based on moral reasoning and moral feeling. In contrast to these, body ethics seek a more profound and humble level of sensibility that is able to implant authenticity into the ethics. Finally, we offer some suggestions related to Watson's caring theory.

Social transfer of pain in mice

PubMed Central

Smith, Monique L.; Hostetler, Caroline M.; Heinricher, Mary M.; Ryabinin, Andrey E.

2016-01-01

A complex relationship exists between the psychosocial environment and the perception and experience of pain, and the mechanisms of the social communication of pain have yet to be elucidated. The present study examined the social communication of pain and demonstrates that “bystander” mice housed and tested in the same room as mice subjected to inflammatory pain or withdrawal from morphine or alcohol develop corresponding hyperalgesia. Olfactory cues mediate the transfer of hyperalgesia to the bystander mice, which can be measured using mechanical, thermal, and chemical tests. Hyperalgesia in bystanders does not co-occur with anxiety or changes in corticosterone and cannot be explained by visually dependent emotional contagion or stress-induced hyperalgesia. These experiments reveal the multifaceted relationship between the social environment and pain behavior and support the use of mice as a model system for investigating these factors. In addition, these experiments highlight the need for proper consideration of how experimental animals are housed and tested. PMID:27774512

Physical and genetic-interaction density reveals functional organization and informs significance cutoffs in genome-wide screens

PubMed Central

Dittmar, John C.; Pierce, Steven; Rothstein, Rodney; Reid, Robert J. D.

2013-01-01

Genome-wide experiments often measure quantitative differences between treated and untreated cells to identify affected strains. For these studies, statistical models are typically used to determine significance cutoffs. We developed a method termed “CLIK” (Cutoff Linked to Interaction Knowledge) that overlays biological knowledge from the interactome on screen results to derive a cutoff. The method takes advantage of the fact that groups of functionally related interacting genes often respond similarly to experimental conditions and, thus, cluster in a ranked list of screen results. We applied CLIK analysis to five screens of the yeast gene disruption library and found that it defined a significance cutoff that differed from traditional statistics. Importantly, verification experiments revealed that the CLIK cutoff correlated with the position in the rank order where the rate of true positives drops off significantly. In addition, the gene sets defined by CLIK analysis often provide further biological perspectives. For example, applying CLIK analysis retrospectively to a screen for cisplatin sensitivity allowed us to identify the importance of the Hrq1 helicase in DNA crosslink repair. Furthermore, we demonstrate the utility of CLIK to determine optimal treatment conditions by analyzing genome-wide screens at multiple rapamycin concentrations. We show that CLIK is an extremely useful tool for evaluating screen quality, determining screen cutoffs, and comparing results between screens. Furthermore, because CLIK uses previously annotated interaction data to determine biologically informed cutoffs, it provides additional insights into screen results, which supplement traditional statistical approaches. PMID:23589890

The Shine-Dalgarno sequence of riboswitch-regulated single mRNAs shows ligand-dependent accessibility bursts

NASA Astrophysics Data System (ADS)

Rinaldi, Arlie J.; Lund, Paul E.; Blanco, Mario R.; Walter, Nils G.

2016-01-01

In response to intracellular signals in Gram-negative bacteria, translational riboswitches--commonly embedded in messenger RNAs (mRNAs)--regulate gene expression through inhibition of translation initiation. It is generally thought that this regulation originates from occlusion of the Shine-Dalgarno (SD) sequence upon ligand binding; however, little direct evidence exists. Here we develop Single Molecule Kinetic Analysis of RNA Transient Structure (SiM-KARTS) to investigate the ligand-dependent accessibility of the SD sequence of an mRNA hosting the 7-aminomethyl-7-deazaguanine (preQ1)-sensing riboswitch. Spike train analysis reveals that individual mRNA molecules alternate between two conformational states, distinguished by `bursts' of probe binding associated with increased SD sequence accessibility. Addition of preQ1 decreases the lifetime of the SD's high-accessibility (bursting) state and prolongs the time between bursts. In addition, ligand-jump experiments reveal imperfect riboswitching of single mRNA molecules. Such complex ligand sensing by individual mRNA molecules rationalizes the nuanced ligand response observed during bulk mRNA translation.

DRBE comet trails

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

Arendt, Richard G., E-mail: Richard.G.Arendt@nasa.gov

2014-12-01

Re-examination of the Cosmic Background Explorer Diffuse Infrared Background Experiment (DIRBE) data reveals the thermal emission of several comet dust trails. The dust trails of 1P/Halley, 169P/NEAT, and 3200 Phaethon have not been previously reported. The known trails of 2P/Encke and 73P/Schwassmann–Wachmann 3 are also seen. The dust trails have 12 and 25 μm surface brightnesses of <0.1 and <0.15 MJy sr{sup −1}, respectively, which is <1% of the zodiacal light intensity. The trails are very difficult to see in any single daily image of the sky, but are evident as rapidly moving linear features in movies of the DIRBEmore » data. Some trails are clearest when crossing through the orbital plane of the parent comet, but others are best seen at high ecliptic latitudes as the Earth passes over or under the dust trail. All these comets have known associations with meteor showers. This re-examination also reveals 1 additional comet and 13 additional asteroids that had not previously been recognized in the DIRBE data.« less

Discounting of Monetary Rewards that are Both Delayed and Probabilistic: Delay and Probability Combine Multiplicatively, not Additively

PubMed Central

Vanderveldt, Ariana; Green, Leonard; Myerson, Joel

2014-01-01

The value of an outcome is affected both by the delay until its receipt (delay discounting) and by the likelihood of its receipt (probability discounting). Despite being well-described by the same hyperboloid function, delay and probability discounting involve fundamentally different processes, as revealed, for example, by the differential effects of reward amount. Previous research has focused on the discounting of delayed and probabilistic rewards separately, with little research examining more complex situations in which rewards are both delayed and probabilistic. In two experiments, participants made choices between smaller rewards that were both immediate and certain and larger rewards that were both delayed and probabilistic. Analyses revealed significant interactions between delay and probability factors inconsistent with an additive model. In contrast, a hyperboloid discounting model in which delay and probability were combined multiplicatively provided an excellent fit to the data. These results suggest that the hyperboloid is a good descriptor of decision making in complicated monetary choice situations like those people encounter in everyday life. PMID:24933696

Language experience enhances early cortical pitch-dependent responses

PubMed Central

Krishnan, Ananthanarayan; Gandour, Jackson T.; Ananthakrishnan, Saradha; Vijayaraghavan, Venkatakrishnan

2014-01-01

Pitch processing at cortical and subcortical stages of processing is shaped by language experience. We recently demonstrated that specific components of the cortical pitch response (CPR) index the more rapidly-changing portions of the high rising Tone 2 of Mandarin Chinese, in addition to marking pitch onset and sound offset. In this study, we examine how language experience (Mandarin vs. English) shapes the processing of different temporal attributes of pitch reflected in the CPR components using stimuli representative of within-category variants of Tone 2. Results showed that the magnitude of CPR components (Na-Pb and Pb-Nb) and the correlation between these two components and pitch acceleration were stronger for the Chinese listeners compared to English listeners for stimuli that fell within the range of Tone 2 citation forms. Discriminant function analysis revealed that the Na-Pb component was more than twice as important as Pb-Nb in grouping listeners by language affiliation. In addition, a stronger stimulus-dependent, rightward asymmetry was observed for the Chinese group at the temporal, but not frontal, electrode sites. This finding may reflect selective recruitment of experience-dependent, pitch-specific mechanisms in right auditory cortex to extract more complex, time-varying pitch patterns. Taken together, these findings suggest that long-term language experience shapes early sensory level processing of pitch in the auditory cortex, and that the sensitivity of the CPR may vary depending on the relative linguistic importance of specific temporal attributes of dynamic pitch. PMID:25506127

Linear and nonlinear stiffness and friction in biological rhythmic movements.

PubMed

Beek, P J; Schmidt, R C; Morris, A W; Sim, M Y; Turvey, M T

1995-11-01

Biological rhythmic movements can be viewed as instances of self-sustained oscillators. Auto-oscillatory phenomena must involve a nonlinear friction function, and usually involve a nonlinear elastic function. With respect to rhythmic movements, the question is: What kinds of nonlinear friction and elastic functions are involved? The nonlinear friction functions of the kind identified by Rayleigh (involving terms such as theta3) and van der Pol (involving terms such as theta2theta), and the nonlinear elastic functions identified by Duffing (involving terms such as theta3), constitute elementary nonlinear components for the assembling of self-sustained oscillators, Recently, additional elementary nonlinear friction and stiffness functions expressed, respectively, through terms such as theta2theta3 and thetatheta2, and a methodology for evaluating the contribution of the elementary components to any given cyclic activity have been identified. The methodology uses a quantification of the continuous deviation of oscillatory motion from ideal (harmonic) motion. Multiple regression of this quantity on the elementary linear and nonlinear terms reveals the individual contribution of each term to the oscillator's non-harmonic behavior. In the present article the methodology was applied to the data from three experiments in which human subjects produced pendular rhythmic movements under manipulations of rotational inertia (experiment 1), rotational inertia and frequency (experiment 2), and rotational inertia and amplitude (experiment 3). The analysis revealed that the pendular oscillators assembled in the three experiments were compositionally rich, braiding linear and nonlinear friction and elastic functions in a manner that depended on the nature of the task.

"We actually care and we want to make the parks better": A qualitative study of youth experiences and perceptions after conducting park audits.

PubMed

Gallerani, David G; Besenyi, Gina M; Wilhelm Stanis, Sonja A; Kaczynski, Andrew T

2017-02-01

This study explored youths' experiences and perceptions about community engagement as a result of participating in a community-based data collection project using paper and mobile technology park environmental audit tools. In July 2014, youth (ages 11-18, n=50) were recruited to participate in nine focus groups after auditing two parks each using paper, electronic, or both versions of the Community Park Audit Tool in Greenville County, SC. The focus groups explored the youths' experiences participating in the project, changes as a result of participation, suggested uses of park audit data collected, and who should use the tools. Four themes emerged related to youths' project participation experiences: two positive (fun and new experiences) and two negative (uncomfortable/unsafe and travel issues). Changes described as a result of participating in the project fell into four themes: increased awareness, motivation for further action, physical activity benefits, and no change. Additionally, youth had numerous suggestions for utilizing the data collected that were coded into six themes: maintenance & aesthetics, feature/amenity addition, online park information, park rating/review system, fundraising, and organizing community projects. Finally, six themes emerged regarding who the youth felt could use the tools: frequent park visitors, community groups/organizations, parks and recreation professionals, adults, youth, and everyone. This study revealed a wealth of information about youth experiences conducting park audits for community health promotion. Understanding youth attitudes and preferences can help advance youth empowerment and civic engagement efforts to promote individual and community health. Copyright © 2016 Elsevier Inc. All rights reserved.

Differing Roles of Functional Movement Variability as Experience Increases in Gymnastics

PubMed Central

Busquets, Albert; Marina, Michel; Davids, Keith; Angulo-Barroso, Rosa

2016-01-01

Current theories, like Ecological Dynamics, propose that inter-trial movement variability is functional when acquiring or refining movement coordination. Here, we examined how age-based experience levels of gymnasts constrained differences in emergent movement pattern variability during task performance. Specifically, we investigated different roles of movement pattern variability when gymnasts in different age groups performed longswings on a high bar, capturing the range of experience from beginner to advanced status. We also investigated the functionality of the relationships between levels of inter-trial variability and longswing amplitude during performance. One-hundred and thirteen male gymnasts in five age groups were observed performing longswings (with three different experience levels: beginners, intermediates and advanced performers). Performance was evaluated by analysis of key events in coordination of longswing focused on the arm-trunk and trunk-thigh segmental relations. Results revealed that 10 of 18 inter-trial variability measures changed significantly as a function of increasing task experience. Four of ten variability measures conformed to a U-shaped function with age implying exploratory strategies amongst beginners and functional adaptive variability amongst advanced performers. Inter-trial variability of arm-trunk coordination variables (6 of 10) conformed to a \\-shaped curve, as values were reduced to complete the longswings. Changes in coordination variability from beginner to intermediate status were largely restrictive, with only one variability measure related to exploration. Data revealed how inter-trial movement variability in gymnastics, relative to performance outcomes, needs careful interpretation, implying different roles as task experience changes. Key points Inter-trial variability while performing longswings on a high bar was assessed in a large sample (113 participants) divided into five age groups (form beginners to advanced gymnasts). Longswing assessment allowed us to evaluate inter-trial variability in representative performance context. Coordination variability presented two different configurations across experience levels depending on the variable of interest: either a U-shaped or a L- or \\-shaped graph. Increased inter-trial variability of the functional phase events offered flexibility to adapt the longswing performance in the advanced gymnasts, while decreasing variability in arm-trunk coordination modes was critical to improve longswing and to achieve the most advanced level. In addition, the relationship between variability measures and the global performance outcome (i.e. the swing amplitude) revealed different functional roles of movement variability (exploratory or restrictive) as a function of changes in experience levels. PMID:27274664

Engineering students' experiences and perceptions of workplace problem solving

NASA Astrophysics Data System (ADS)

Pan, Rui

In this study, I interviewed 22 engineering Co-Op students about their workplace problem solving experiences and reflections and explored: 1) Of Co-Op students who experienced workplace problem solving, what are the different ways in which students experience workplace problem solving? 2) How do students perceive a) the differences between workplace problem solving and classroom problem solving and b) in what areas are they prepared by their college education to solve workplace problems? To answer my first research question, I analyzed data through the lens of phenomenography and I conducted thematic analysis to answer my second research question. The results of this study have implications for engineering education and engineering practice. Specifically, the results reveal the different ways students experience workplace problem solving, which provide engineering educators and practicing engineers a better understanding of the nature of workplace engineering. In addition, the results indicate that there is still a gap between classroom engineering and workplace engineering. For engineering educators who aspire to prepare students to be future engineers, it is imperative to design problem solving experiences that can better prepare students with workplace competency.

Image dependency in the recognition of newly learnt faces.

PubMed

Longmore, Christopher A; Santos, Isabel M; Silva, Carlos F; Hall, Abi; Faloyin, Dipo; Little, Emily

2017-05-01

Research investigating the effect of lighting and viewpoint changes on unfamiliar and newly learnt faces has revealed that such recognition is highly image dependent and that changes in either of these leads to poor recognition accuracy. Three experiments are reported to extend these findings by examining the effect of apparent age on the recognition of newly learnt faces. Experiment 1 investigated the ability to generalize to novel ages of a face after learning a single image. It was found that recognition was best for the learnt image with performance falling the greater the dissimilarity between the study and test images. Experiments 2 and 3 examined whether learning two images aids subsequent recognition of a novel image. The results indicated that interpolation between two studied images (Experiment 2) provided some additional benefit over learning a single view, but that this did not extend to extrapolation (Experiment 3). The results from all studies suggest that recognition was driven primarily by pictorial codes and that the recognition of faces learnt from a limited number of sources operates on stored images of faces as opposed to more abstract, structural, representations.

Stimulus generalization as a mechanism for learning to trust

PubMed Central

FeldmanHall, Oriel; Dunsmoor, Joseph E.; Tompary, Alexa; Hunter, Lindsay E.; Todorov, Alexander; Phelps, Elizabeth A.

2018-01-01

How do humans learn to trust unfamiliar others? Decisions in the absence of direct knowledge rely on our ability to generalize from past experiences and are often shaped by the degree of similarity between prior experience and novel situations. Here, we leverage a stimulus generalization framework to examine how perceptual similarity between known individuals and unfamiliar strangers shapes social learning. In a behavioral study, subjects play an iterative trust game with three partners who exhibit highly trustworthy, somewhat trustworthy, or highly untrustworthy behavior. After learning who can be trusted, subjects select new partners for a second game. Unbeknownst to subjects, each potential new partner was parametrically morphed with one of the three original players. Results reveal that subjects prefer to play with strangers who implicitly resemble the original player they previously learned was trustworthy and avoid playing with strangers resembling the untrustworthy player. These decisions to trust or distrust strangers formed a generalization gradient that converged toward baseline as perceptual similarity to the original player diminished. In a second imaging experiment we replicate these behavioral gradients and leverage multivariate pattern similarity analyses to reveal that a tuning profile of activation patterns in the amygdala selectively captures increasing perceptions of untrustworthiness. We additionally observe that within the caudate adaptive choices to trust rely on neural activation patterns similar to those elicited when learning about unrelated, but perceptually familiar, individuals. Together, these findings suggest an associative learning mechanism efficiently deploys moral information encoded from past experiences to guide future choice. PMID:29378964

The effect of alum addition on microbial communities in poultry litter.

PubMed

Rothrock, M J; Cook, K L; Warren, J G; Sistani, K

2008-08-01

Alum [Al(2)(SO(4))(3).14H(2)O] is a common poultry litter amendment used to decrease water-soluble phosphorus or reduce ammonia volatilization, or both. Although the physiochemical effects of alum addition have been well researched, little attention has been given to the poultry litter microbial communities. The goal of this study was to use molecular biological methods [denaturing gradient gel electrophoresis (DGGE), community cloning, and quantitative real-time PCR] to characterize general, group-specific and pathogenic microbial communities in alum (10% wt/wt) and non-alum-treated litter. According to quantitative real-time PCR analyses, alum addition to the poultry litter resulted in significant reductions in both Campylobacter jejuni and Escherichia coli concentrations by the end of the first month of the experiment (3 log and 2 log, respectively). The concentrations of Salmonella spp. were below detection (<5 x 10(3) cell.g(-1) of litter) for the entire experiment. The DGGE analyses revealed significant reductions in the Clostridium/Eubacterium and low %GC gram-positive groups in the alum-treated litters by the end of the first month, with no bands detectable for either group after 8 wk of incubation. Conversely, minimal effects of alum addition were observed in the Actinomycetes community. The most significant shift in the microbial community (based on DGGE analyses) occurred in the fungal population, with a large increase in diversity and abundance within 1 mo of alum addition (1 dominant band on d 0 to 9 dominant bands at 4 wk). Specifically, the incidence of Aspergillus spp. increased from 0 to 50% of the sequences in fungal clone libraries (n = 80) over the course of the experiment. This suggests that the addition of alum to poultry litter potentially shifts the microbial populations from bacterially dominated to dominated by fungi. The ramifications of this shift in dominance are still unknown, and future work will be aimed at characterizing these fungi and elucidating their role in the acidified litter environment.

Stacking sequence and interlayer coupling in few-layer graphene revealed by in situ imaging

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

Wang, Zhu-Jun; Dong, Jichen; Cui, Yi

In the transition from graphene to graphite, the addition of each individual graphene layer modifies the electronic structure and produces a different material with unique properties. Controlled growth of few-layer graphene is therefore of fundamental interest and will provide access to materials with engineered electronic structure. Here we combine isothermal growth and etching experiments with in situ scanning electron microscopy to reveal the stacking sequence and interlayer coupling strength in few-layer graphene. The observed layer-dependent etching rates reveal the relative strength of the graphene graphene and graphene substrate interaction and the resulting mode of adlayer growth. Scanning tunnelling microscopy andmore » density functional theory calculations confirm a strong coupling between graphene edge atoms and platinum. Simulated etching confirms that etching can be viewed as reversed growth. This work demonstrates that real-time imaging under controlled atmosphere is a powerful method for designing synthesis protocols for sp2 carbon nanostructures in between graphene and graphite.« less

Stacking sequence and interlayer coupling in few-layer graphene revealed by in situ imaging

DOE PAGES

Wang, Zhu-Jun; Dong, Jichen; Cui, Yi; ...

2016-10-19

In the transition from graphene to graphite, the addition of each individual graphene layer modifies the electronic structure and produces a different material with unique properties. Controlled growth of few-layer graphene is therefore of fundamental interest and will provide access to materials with engineered electronic structure. Here we combine isothermal growth and etching experiments with in situ scanning electron microscopy to reveal the stacking sequence and interlayer coupling strength in few-layer graphene. The observed layer-dependent etching rates reveal the relative strength of the graphene graphene and graphene substrate interaction and the resulting mode of adlayer growth. Scanning tunnelling microscopy andmore » density functional theory calculations confirm a strong coupling between graphene edge atoms and platinum. Simulated etching confirms that etching can be viewed as reversed growth. This work demonstrates that real-time imaging under controlled atmosphere is a powerful method for designing synthesis protocols for sp2 carbon nanostructures in between graphene and graphite.« less

Stacking sequence and interlayer coupling in few-layer graphene revealed by in situ imaging

PubMed Central

Wang, Zhu-Jun; Dong, Jichen; Cui, Yi; Eres, Gyula; Timpe, Olaf; Fu, Qiang; Ding, Feng; Schloegl, R.; Willinger, Marc-Georg

2016-01-01

In the transition from graphene to graphite, the addition of each individual graphene layer modifies the electronic structure and produces a different material with unique properties. Controlled growth of few-layer graphene is therefore of fundamental interest and will provide access to materials with engineered electronic structure. Here we combine isothermal growth and etching experiments with in situ scanning electron microscopy to reveal the stacking sequence and interlayer coupling strength in few-layer graphene. The observed layer-dependent etching rates reveal the relative strength of the graphene–graphene and graphene–substrate interaction and the resulting mode of adlayer growth. Scanning tunnelling microscopy and density functional theory calculations confirm a strong coupling between graphene edge atoms and platinum. Simulated etching confirms that etching can be viewed as reversed growth. This work demonstrates that real-time imaging under controlled atmosphere is a powerful method for designing synthesis protocols for sp2 carbon nanostructures in between graphene and graphite. PMID:27759024

On the additive effects of stimulus quality and word frequency in lexical decision: evidence for opposing interactive influences revealed by RT distributional analyses.

PubMed

Yap, Melvin J; Balota, David A; Tse, Chi-Shing; Besner, Derek

2008-05-01

The joint effects of stimulus quality and word frequency in lexical decision were examined in 4 experiments as a function of nonword type (legal nonwords, e.g., BRONE, vs. pseudohomophones, e.g., BRANE). When familiarity was a viable dimension for word-nonword discrimination, as when legal nonwords were used, additive effects of stimulus quality and word frequency were observed in both means and distributional characteristics of the response-time distributions. In contrast, when the utility of familiarity was undermined by using pseudohomophones, additivity was observed in the means but not in distributional characteristics. Specifically, opposing interactive effects in the underlying distribution were observed, producing apparent additivity in means. These findings are consistent with the suggestion that, when familiarity is deemphasized in lexical decision, cascaded processing between letter and word levels is in play, whereas, when familiarity is a viable dimension for word-nonword discrimination, processing is discrete.

Increase of methane formation by ethanol addition during continuous fermentation of biogas sludge.

PubMed

Refai, Sarah; Wassmann, Kati; van Helmont, Sebastian; Berger, Stefanie; Deppenmeier, Uwe

2014-12-01

Very recently, it was shown that the addition of acetate or ethanol led to enhanced biogas formation rates during an observation period of 24 h. To determine if increased methane production rates due to ethanol addition can be maintained over longer time periods, continuous reactors filled with biogas sludge were developed which were fed with the same substrates as the full-scale reactor from which the sludge was derived. These reactors are well reflected conditions of a full-scale biogas plant during a period of 14 days. When the fermenters were pulsed with 50-100 mM ethanol, biomethanation increased by 50-150 %, depending on the composition of the biogas sludge. It was also possible to increase methane formation significantly when 10-20 mM pure ethanol or ethanolic solutions (e.g. beer) were added daily. In summary, the experiments revealed that "normal" methane production continued to take place, but ethanol led to production of additional methane.

Interactions of cinnamaldehyde and its metabolite cinnamic acid with human serum albumin and interference of other food additives.

PubMed

Sun, Qiaomei; Yang, Hongqin; Tang, Peixiao; Liu, Jiuyang; Wang, Wan; Li, Hui

2018-03-15

Considering the adverse effect of food additives on humans, thorough research of their physiological effects at the molecular level is important. The interactions of cinnamaldehyde (CNMA), a food perfume, and its major metabolite cinnamic acid (CA) with human serum albumin (HSA) were examined by multiple-spectroscopies. NMR analysis revealed CNMA and CA both bound to HSA, and STD-NMR experiments established CNMA and CA primarily interacted with site I and site II of HSA, respectively. The ligands caused strong quenching of HSA fluorescence through a static quenching mechanism, with hydrophobic and electrostatic interaction between CNMA/CA and HSA, respectively. UV-vis absorption and CD results showed ligands induced secondary structure changes of HSA. Binding configurations were proved by docking method. Furthermore, binding constants of CNMA/CA-HSA systems were influenced by the addition of four other food additives. These studies have increased our knowledge regarding the safety and biological action of CNMA and CA. Copyright © 2017 Elsevier Ltd. All rights reserved.

THE TRANSITION FROM MOTHER-OF-ONE TO MOTHER-OF-TWO: MOTHERS' PERCEPTIONS OF THEMSELVES AND THEIR RELATIONSHIPS WITH THEIR FIRSTBORN CHILDREN.

PubMed

Chapman, Jennifer K; Hart, Sybil L

2017-07-01

This qualitative study aimed to explore mothers' perceptions of the transition to second-time motherhood, and advance methodology for supporting mothers during this transition. Fifty-seven pregnant mothers and their firstborn children (M age = 30.3 months) participated in a laboratory procedure in which the mother exposed her child to a brief episode of differential treatment. The episode was designed to simulate an expected experience of caregiving that would occur after the birth of a second child. During a postnatal visit (M=5.72 weeks following childbirth), mothers provided written feedback on their perceptions of the transition and the contribution of the laboratory experience to that transition. Qualitative content analysis revealed that mothers approached the birth of a second child with apprehension. Intrapersonal themes revealed that participation in the procedure shaped mothers' understanding of their expanded maternal roles by enhancing their sense of preparedness and confidence in their abilities to support their children. Interpersonal themes revealed that participation helped mothers appreciate the magnitude of the challenge that their children would face and gave mothers reason to believe that their children would adjust successfully. Findings are discussed in terms of their potential contribution toward developing methodology for helping mothers prepare for the addition of a second child. © 2017 Michigan Association for Infant Mental Health.

Product placement of computer games in cyberspace.

PubMed

Yang, Heng-Li; Wang, Cheng-Shu

2008-08-01

Computer games are considered an emerging media and are even regarded as an advertising channel. By a three-phase experiment, this study investigated the advertising effectiveness of computer games for different product placement forms, product types, and their combinations. As the statistical results revealed, computer games are appropriate for placement advertising. Additionally, different product types and placement forms produced different advertising effectiveness. Optimum combinations of product types and placement forms existed. An advertisement design model is proposed for use in game design environments. Some suggestions are given for advertisers and game companies respectively.

Initial shifts in nitrogen impact on ecosystem carbon fluxes in an alpine meadow: patterns and causes

NASA Astrophysics Data System (ADS)

Song, Bing; Sun, Jian; Zhou, Qingping; Zong, Ning; Li, Linghao; Niu, Shuli

2017-09-01

Increases in nitrogen (N) deposition can greatly stimulate ecosystem net carbon (C) sequestration through positive N-induced effects on plant productivity. However, how net ecosystem CO2 exchange (NEE) and its components respond to different N addition rates remains unclear. Using an N addition gradient experiment (six levels: 0, 2, 4, 8, 16, 32 gN m-2 yr-1) in an alpine meadow on the Qinghai-Tibetan Plateau, we explored the responses of different ecosystem C fluxes to an N addition gradient and revealed mechanisms underlying the dynamic responses. Results showed that NEE, ecosystem respiration (ER), and gross ecosystem production (GEP) all increased linearly with N addition rates in the first year of treatment but shifted to N saturation responses in the second year with the highest NEE (-7.77 ± 0.48 µmol m-2 s-1) occurring under an N addition rate of 8 gN m-2 yr-1. The saturation responses of NEE and GEP were caused by N-induced accumulation of standing litter, which limited light availability for plant growth under high N addition. The saturation response of ER was mainly due to an N-induced saturation response of aboveground plant respiration and decreasing soil microbial respiration along the N addition gradient, while decreases in soil microbial respiration under high N addition were caused by N-induced reductions in soil pH. We also found that various components of ER, including aboveground plant respiration, soil respiration, root respiration, and microbial respiration, responded differentially to the N addition gradient. These results reveal temporal dynamics of N impacts and the rapid shift in ecosystem C fluxes from N limitation to N saturation. Our findings bring evidence of short-term initial shifts in responses of ecosystem C fluxes to increases in N deposition, which should be considered when predicting long-term changes in ecosystem net C sequestration.

The Viking biology results

NASA Technical Reports Server (NTRS)

Klein, Harold P.

1989-01-01

A brief review of the purposes and the results from the Viking Biology experiments is presented, in the expectation that the lessons learned from this mission will be useful in planning future approaches to the biological exploration of Mars. Since so little was then known about potential micro-environments on Mars, three different experiments were included in the Viking mission, each one based on different assumptions about what Martian organisms might be like. In addition to the Viking Biology Instrument (VBI), important corollary information was obtained from the Viking lander imaging system and from the molecular analysis experiments that were conducted using the gas chromatograph-mass spectrometer (GCMS) instrument. No biological objects were noted by the lander imaging instrument. The GCMS did not detect any organic compounds. A description of the tests conducted by the Gas Exchange Experiment, the Labeled Release experiment, and the Pyrolytic Release experiment is given. Results are discussed. Taken as a whole, the Viking data yielded no unequivocal evidence for a Martian biota at either landing site. The results also revealed the presence of one or more reactive oxidants in the surface material and these need to be further characterized, as does the range of micro-environments, before embarking upon future searches for extant life on Mars.

An instrument for in situ time-resolved X-ray imaging and diffraction of laser powder bed fusion additive manufacturing processes

NASA Astrophysics Data System (ADS)

Calta, Nicholas P.; Wang, Jenny; Kiss, Andrew M.; Martin, Aiden A.; Depond, Philip J.; Guss, Gabriel M.; Thampy, Vivek; Fong, Anthony Y.; Weker, Johanna Nelson; Stone, Kevin H.; Tassone, Christopher J.; Kramer, Matthew J.; Toney, Michael F.; Van Buuren, Anthony; Matthews, Manyalibo J.

2018-05-01

In situ X-ray-based measurements of the laser powder bed fusion (LPBF) additive manufacturing process produce unique data for model validation and improved process understanding. Synchrotron X-ray imaging and diffraction provide high resolution, bulk sensitive information with sufficient sampling rates to probe melt pool dynamics as well as phase and microstructure evolution. Here, we describe a laboratory-scale LPBF test bed designed to accommodate diffraction and imaging experiments at a synchrotron X-ray source during LPBF operation. We also present experimental results using Ti-6Al-4V, a widely used aerospace alloy, as a model system. Both imaging and diffraction experiments were carried out at the Stanford Synchrotron Radiation Lightsource. Melt pool dynamics were imaged at frame rates up to 4 kHz with a ˜1.1 μm effective pixel size and revealed the formation of keyhole pores along the melt track due to vapor recoil forces. Diffraction experiments at sampling rates of 1 kHz captured phase evolution and lattice contraction during the rapid cooling present in LPBF within a ˜50 × 100 μm area. We also discuss the utility of these measurements for model validation and process improvement.

Mild and Selective Hydrozirconation of Amides to Aldehydes Using Cp2Zr(H)Cl

PubMed Central

Spletstoser, Jared T.; White, Jonathan M.; Tunoori, Ashok Rao; Georg, Gunda I.

2008-01-01

An investigation of the use of Cp2Zr(H)Cl (Schwartz’s reagent) to reduce a variety of amides to the corresponding aldehydes under very mild reaction conditions and in high yields is reported. A range of tertiary amides, including Weinreb’s amide, can be converted directly to the corresponding aldehydes with remarkable chemoselectivity. Primary and secondary amides proved to be viable substrates for reduction as well, although the yields were somewhat diminished compared to the corresponding tertiary amides. Results from NMR experiments suggested the presence of a stable, 18-electron zirconacycle intermediate that presumably affords the aldehyde upon water or silica gel workup. A series of competition experiments revealed a preference of the reagent for substrates in which the lone pair of the nitrogen is electron releasing and thus more delocalized across the amide bond by resonance. This trend accounts for the observed excellent selectivity for tertiary amides versus esters. Experiments regarding the solvent dependence of the reaction suggested a kinetic profile similar to that postulated for the hydrozirconation of alkenes and alkynes. Addition of p-anisidine to the reaction intermediate resulted in the formation of the corresponding imine mimicking the addition of water that forms the aldehyde. PMID:17315870

Cadence Tracking and Disturbance Rejection in Functional Electrical Stimulation Cycling for Paraplegic Subjects: A Case Study.

PubMed

Fonseca, Lucas O da; Bó, Antônio P L; Guimarães, Juliana A; Gutierrez, Miguel E; Fachin-Martins, Emerson

2017-11-01

Functional electrical stimulation cycling has been proposed as an assistive technology with numerous health and fitness benefits for people with spinal cord injury, such as improvement in cardiovascular function, increase in muscular mass, and reduction of bone mass loss. However, some limitations, for example, lack of optimal control strategies that would delay fatigue, may still prevent this technology from achieving its full potential. In this work, we performed experiments on a person with complete spinal cord injury using a stationary tadpole trike when both cadence tracking and disturbance rejection were evaluated. In addition, two sets of experiments were conducted 6 months apart and considering activation of different muscles. The results showed that reference tracking is achieved above the cadence of 25 rpm with mean absolute errors between 1.9 and 10% when only quadriceps are activated. The disturbance test revealed that interferences may drop the cadence but do not interrupt a continuous movement if the cadence does not drop below 25 rpm, again when only quadriceps are activated. When other muscle groups were added, strong spasticity caused larger errors on reference tracking, but not when a disturbance was applied. In addition, spasticity caused the last experiments to result in less smooth cycling. © 2017 International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.

The influence of linguistic and cognitive factors on the time course of verb-based implicit causality.

PubMed

Koornneef, Arnout; Dotlačil, Jakub; van den Broek, Paul; Sanders, Ted

2016-01-01

In three eye-tracking experiments the influence of the Dutch causal connective "want" (because) and the working memory capacity of readers on the usage of verb-based implicit causality was examined. Experiments 1 and 2 showed that although a causal connective is not required to activate implicit causality information during reading, effects of implicit causality surfaced more rapidly and were more pronounced when a connective was present in the discourse than when it was absent. In addition, Experiment 3 revealed that-in contrast to previous claims-the activation of implicit causality is not a resource-consuming mental operation. Moreover, readers with higher and lower working memory capacities behaved differently in a dual-task situation. Higher span readers were more likely to use implicit causality when they had all their working memory resources at their disposal. Lower span readers showed the opposite pattern as they were more likely to use the implicit causality cue in the case of an additional working memory load. The results emphasize that both linguistic and cognitive factors mediate the impact of implicit causality on text comprehension. The implications of these results are discussed in terms of the ongoing controversies in the literature-that is, the focusing-integration debate and the debates on the source of implicit causality.

Polyaluminium chloride as an alternative to alum for the direct filtration of drinking water.

PubMed

Zarchi, Idit; Friedler, Eran; Rebhun, Menahem

2013-01-01

The efficiency of various polyaluminium chloride coagulants (PACls) was compared to the efficiency of aluminium sulfate (alum) in the coagulation-flocculation process preceding direct filtration in drinking water treatment. The comparative study consisted of two separate yet complementary series of experiments: the first series included short (5-7 h) and long (24 h) filter runs conducted at a pilot filtration plant equipped with large filter columns that simulated full-scale filters. Partially treated surface water from the Sea of Galilee, characterized by very low turbidity (-1 NTU), was used. In the second series of experiments, speciation of aluminium in situ was investigated using the ferron assay method. Results from the pilot-scale study indicate that most PACls were as or more efficient a coagulant as alum for direct filtration of surface water without requiring acid addition for pH adjustment and subsequent base addition for re-stabilizing the water. Consequently, cost analysis of the chemicals needed for the process showed that treatment with PACl would be significantly less costly than treatment with alum. The aluminium speciation experiments revealed that the performance of the coagulant is more influenced by the species present during the coagulation process than those present in the original reagents.

An instrument for in situ time-resolved X-ray imaging and diffraction of laser powder bed fusion additive manufacturing processes.

PubMed

Calta, Nicholas P; Wang, Jenny; Kiss, Andrew M; Martin, Aiden A; Depond, Philip J; Guss, Gabriel M; Thampy, Vivek; Fong, Anthony Y; Weker, Johanna Nelson; Stone, Kevin H; Tassone, Christopher J; Kramer, Matthew J; Toney, Michael F; Van Buuren, Anthony; Matthews, Manyalibo J

2018-05-01

In situ X-ray-based measurements of the laser powder bed fusion (LPBF) additive manufacturing process produce unique data for model validation and improved process understanding. Synchrotron X-ray imaging and diffraction provide high resolution, bulk sensitive information with sufficient sampling rates to probe melt pool dynamics as well as phase and microstructure evolution. Here, we describe a laboratory-scale LPBF test bed designed to accommodate diffraction and imaging experiments at a synchrotron X-ray source during LPBF operation. We also present experimental results using Ti-6Al-4V, a widely used aerospace alloy, as a model system. Both imaging and diffraction experiments were carried out at the Stanford Synchrotron Radiation Lightsource. Melt pool dynamics were imaged at frame rates up to 4 kHz with a ∼1.1 μm effective pixel size and revealed the formation of keyhole pores along the melt track due to vapor recoil forces. Diffraction experiments at sampling rates of 1 kHz captured phase evolution and lattice contraction during the rapid cooling present in LPBF within a ∼50 × 100 μm area. We also discuss the utility of these measurements for model validation and process improvement.

An instrument for in situ time-resolved X-ray imaging and diffraction of laser powder bed fusion additive manufacturing processes

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

Calta, Nicholas P.; Wang, Jenny; Kiss, Andrew M.

In situ X-ray-based measurements of the laser powder bed fusion (LPBF) additive manufacturing process produce unique data for model validation and improved process understanding. Synchrotron X-ray imaging and diffraction provide high resolution, bulk sensitive information with sufficient sampling rates to probe melt pool dynamics as well as phase and microstructure evolution. Here, we describe a laboratory-scale LPBF test bed designed to accommodate diffraction and imaging experiments at a synchrotron X-ray source during LPBF operation. We also present experimental results using Ti-6Al-4V, a widely used aerospace alloy, as a model system. Both imaging and diffraction experiments were carried out at themore » Stanford Synchrotron Radiation Lightsource. Melt pool dynamics were imaged at frame rates up to 4 kHz with a ~1.1 μm effective pixel size and revealed the formation of keyhole pores along the melt track due to vapor recoil forces. Diffraction experiments at sampling rates of 1 kHz captured phase evolution and lattice contraction during the rapid cooling present in LPBF within a ~50 × 100 μm area. In conclusion, we also discuss the utility of these measurements for model validation and process improvement.« less

Locus of emotion: the effect of task order and age on emotion perceived and emotion felt in response to music.

PubMed

Schubert, Emery

2007-01-01

The relationship between emotions perceived to be expressed (external locus EL) versus emotions felt (internal locus--IL) in response to music was examined using 5 contrasting pieces of Romantic, Western art music. The main hypothesis tested was that emotion expressed along the dimensions of emotional-strength, valence, and arousal were lower in magnitude for IL than EL. IL and EL judgments made together after one listening (Experiment 2, n = 18) produced less differentiated responses than when each task was performed after separate listenings (Experiment 1, n = 28). This merging of responses in the locus-task-together condition started to disappear as statistical power was increased. Statistical power was increased by recruiting an additional subject pool of elderly individuals (Experiment 3, n = 19, mean age 75 years). Their valence responses were more positive, and their emotional-strength ratings were generally lower, compared to their younger counterparts. Overall data analysis revealed that IL responses fluctuated slightly more than EL emotions, meaning that the latter are more stable. An additional dimension of dominance-submissiveness was also examined, and was useful in differentiating between pieces, but did not return a difference between IL and EL. Some therapy applications of these findings are discussed.

An instrument for in situ time-resolved X-ray imaging and diffraction of laser powder bed fusion additive manufacturing processes

DOE PAGES

Calta, Nicholas P.; Wang, Jenny; Kiss, Andrew M.; ...

2018-05-01

In situ X-ray-based measurements of the laser powder bed fusion (LPBF) additive manufacturing process produce unique data for model validation and improved process understanding. Synchrotron X-ray imaging and diffraction provide high resolution, bulk sensitive information with sufficient sampling rates to probe melt pool dynamics as well as phase and microstructure evolution. Here, we describe a laboratory-scale LPBF test bed designed to accommodate diffraction and imaging experiments at a synchrotron X-ray source during LPBF operation. We also present experimental results using Ti-6Al-4V, a widely used aerospace alloy, as a model system. Both imaging and diffraction experiments were carried out at themore » Stanford Synchrotron Radiation Lightsource. Melt pool dynamics were imaged at frame rates up to 4 kHz with a ~1.1 μm effective pixel size and revealed the formation of keyhole pores along the melt track due to vapor recoil forces. Diffraction experiments at sampling rates of 1 kHz captured phase evolution and lattice contraction during the rapid cooling present in LPBF within a ~50 × 100 μm area. In conclusion, we also discuss the utility of these measurements for model validation and process improvement.« less

Aerobic Hydrogen Production via Nitrogenase in Azotobacter vinelandii CA6

PubMed Central

Noar, Jesse; Loveless, Telisa; Navarro-Herrero, José Luis; Olson, Jonathan W.

2015-01-01

The diazotroph Azotobacter vinelandii possesses three distinct nitrogenase isoenzymes, all of which produce molecular hydrogen as a by-product. In batch cultures, A. vinelandii strain CA6, a mutant of strain CA, displays multiple phenotypes distinct from its parent: tolerance to tungstate, impaired growth and molybdate transport, and increased hydrogen evolution. Determining and comparing the genomic sequences of strains CA and CA6 revealed a large deletion in CA6's genome, encompassing genes related to molybdate and iron transport and hydrogen reoxidation. A series of iron uptake analyses and chemostat culture experiments confirmed iron transport impairment and showed that the addition of fixed nitrogen (ammonia) resulted in cessation of hydrogen production. Additional chemostat experiments compared the hydrogen-producing parameters of different strains: in iron-sufficient, tungstate-free conditions, strain CA6's yields were identical to those of a strain lacking only a single hydrogenase gene. However, in the presence of tungstate, CA6 produced several times more hydrogen. A. vinelandii may hold promise for developing a novel strategy for production of hydrogen as an energy compound. PMID:25911479

Tipping points in adolescent adjustment: predicting social functioning from adolescents' conflict with parents and friends.

PubMed

Ehrlich, Katherine B; Dykas, Matthew J; Cassidy, Jude

2012-10-01

Despite widespread interest in examining the role of conflict for adolescent development, researchers only rarely have examined adolescents' experiences of conflict across relationships. The present study examined how adolescents' experiences of conflict with parents and friends were linked to their social functioning. Adolescents (n = 189) and their mothers and fathers participated in semistructured discussions about areas of parent-adolescent conflict in the laboratory. In addition, adolescents reported about conflict in their best friendships, and peers reported about adolescents' social acceptance and behavior in social settings. Parent-adolescent conflict was associated with peer-reported aggression and delinquency, and friendship conflict was associated with delinquency and prosocial behavior. In addition, significant Parent-Adolescent Conflict × Friend-Adolescent Conflict interactions revealed that parent-adolescent conflict was associated with poor social functioning only when conflict with best friends was also high. The findings suggest that consideration of conflict across relationships may yield insight into the specific contexts in which conflict is associated with negative outcomes for adolescents. (PsycINFO Database Record (c) 2012 APA, all rights reserved).

Upward and downward facing high mass flux spray cooling with additives: A novel technique to enhance the heat removal rate at high initial surface temperature

NASA Astrophysics Data System (ADS)

Pati, A. R.; Kumar, A.; Mohapatra, S. S.

2018-06-01

The objective of the current work is to enhance the spray cooling by changing the orientation of the nozzle with different additives (acetone, methanol, ethanol, benzene, n-hexane, tween 20 and salt) in water. The experiments are carried out by upward, downward and both upward and downward facing sprays. The optimization result depicts that the spray produced by upward facing spray gives higher heat flux than the downward facing spray and also cooling by both the upward and downward facing spray simultaneously produces better result than the individual. Further experiments with both upward and downward facing spray by using different coolants reveal that in case of cooling by ethanol (500 ppm) + water mixture, the maximum enhancement of surface heat flux ( 2.57 MW/m2) and cooling rate (204 °C/s) is observed. However, the minimum surface heat flux is achieved in case of methanol (100 ppm) + water due to higher contact angle (710) among all the considered coolants.

Processes of deep terrestrial mantles and cores

NASA Technical Reports Server (NTRS)

Jeanloz, Raymond

1991-01-01

Ultrahigh pressure experiments are currently focused on revealing processes occurring deep inside planets. This is in addition to the traditional emphasis on the constitution of planetary interiors, such as the identification of the high pressure perovskite phase of (Mg,Fe)SiO3 as the predominant mineral inside the Earth, and probably Venus. For example, experiments show that the mechanism of geochemical differentiation, separation of partial melts, differs fundamentally in the lower mantles of Earth and Venus than at near surface conditions. In addition to structural transformations, changes in chemical bonding caused by pressure can also be significant for planetary interiors. Measurements of AC and DC electrical conductivity can be obtained at ultrahigh pressures and temperatures, to greater than 80 GPa and 3000 K simultaneously, using the laser heated diamond cell. Anhydrous lower mantle assemblages (perovskite + or - oxide phases) exhibit an electrical conductivity that depends strongly on Fe content. Contrary to traditional assumptions, temperature affects the conductivity of lower mantle assemblages relatively little. The Earth's deep focus seismicity can be explained by the recycling of water into the mantle.

Patients' experiences of self-disclosure in psychotherapy: the effects of gender and gender role identification.

PubMed

Pattee, Dailey; Farber, Barry A

2008-05-01

This study examined the effects of gender and gender role identification on 223 patients' experiences of self-disclosure in psychotherapy. Factor analysis of the Disclosure-to-Therapist Inventory-IV revealed two dimensions: a distress factor, reflecting the perceived difficulty and the anticipated impact of disclosures on the therapist, and an openness factor, reflecting the extent and perceived importance of disclosures and the interpersonal connection experienced during them. Female patients working with female therapists experienced greater distress in disclosure than male patients working with female therapists; in addition, patients with more flexible gender role identifications (i.e., androgynous) experienced greater openness than those with more traditional gender identifications. Findings suggest a need for greater discussion in therapy of the effects of gender on disclosure.

Educational pathways of Black women physicists: Stories of experiencing and overcoming obstacles in life

NASA Astrophysics Data System (ADS)

Rosa, Katemari; Mensah, Felicia Moore

2016-12-01

[This paper is part of the Focused Collection on Gender in Physics.] This is an empirical study on the underrepresentation of people of color in scientific careers. Grounded in critical race theory, the paper examines the lived experiences of six Black women physicists and addresses obstacles faced in their career paths and strategies used to overcome these obstacles. Data for this study were collected through semistructured interviews and coded for emergent themes. The findings reveal that college recruitment and funding were fundamental for these women to choose physics over other STEM fields. In addition, Black women experience unique challenges of socialization in STEM, particularly by exclusion of study groups. We suggest physics departments provide a more inclusive environment to support Black women in science.

Functional MRI reveals expert-novice differences during sport-related anticipation.

PubMed

Wright, Michael J; Bishop, Daniel T; Jackson, Robin C; Abernethy, Bruce

2010-01-27

We examined the effect of expertise on cortical activation during sports anticipation using functional MRI. In experiment 1, recreational players predicted badminton stroke direction and the pattern of active clusters was consistent with a proposed perception-of-action network. This pattern was not replicated in a stimulus-matched, action-unrelated control task. In experiment 2, players of three different skill levels anticipated stroke direction from clips occluded either 160 ms before or 80 ms after racquet-shuttle contact. Early-occluded sequences produced more activation than late-occluded sequences overall, in most cortical regions of interest, but experts showed an additional enhancement in medial, dorsolateral and ventrolateral frontal cortex. Anticipation in open-skill sports engages cortical areas integral to observing and understanding others' actions; such activity is enhanced in experts.

The assessment of professional competence: building blocks for theory development.

PubMed

van der Vleuten, C P M; Schuwirth, L W T; Scheele, F; Driessen, E W; Hodges, B

2010-12-01

This article presents lessons learnt from experiences with assessment of professional competence. Based on Miller's pyramid, a distinction is made between established assessment technology for assessing 'knows', 'knowing how' and 'showing how' and more recent developments in the assessment of (clinical) performance at the 'does' level. Some general lessons are derived from research of and experiences with the established assessment technology. Here, many paradoxes are revealed and empirical outcomes are often counterintuitive. Instruments for assessing the 'does' level are classified and described, and additional general lessons for this area of performance assessment are derived. These lessons can also be read as general principles of assessment (programmes) and may provide theoretical building blocks to underpin appropriate and state-of-the-art assessment practices. Copyright © 2010 Elsevier Ltd. All rights reserved.

Study on interaction of mangiferin to insulin and glucagon in ternary system

NASA Astrophysics Data System (ADS)

Lin, Hui; Chen, Rui; Liu, Xiaoyan; Sheng, Fenling; Zhang, Haixia

2010-05-01

The binding of mangiferin to insulin and glucagon was investigated in the presence and absence of another Peptide by optical spectroscopy. Fluorescence titration experiments revealed that mangiferin quenched the intrinsic fluorescence of insulin and glucagon by static quenching. The ratios of binding constants of glucagon-mangiferin to insulin-mangiferin at different temperatures were calculated in "pure" and ternary system, respectively. The results indicated that the Peptides were competitive with each other to act on mangiferin. Values of the thermodynamic parameters and the experiments of pH effect proved that the key interacting forces between mangiferin and the Peptides were hydrophobic interaction. In addition, UV-vis absorption, synchronous fluorescence and Fourier transform infrared measurements showed that the conformation of insulin and glucagon were changed after adding mangiferin.

Pattern Analysis in Social Networks with Dynamic Connections

NASA Astrophysics Data System (ADS)

Wu, Yu; Zhang, Yu

In this paper, we explore how decentralized local interactions of autonomous agents in a network relate to collective behaviors. Most existing work in this area models social network in which agent relations are fixed; instead, we focus on dynamic social networks where agents can rationally adjust their neighborhoods based on their individual interests. We propose a new connection evaluation rule called the Highest Weighted Reward (HWR) rule, with which agents dynamically choose their neighbors in order to maximize their own utilities based on the rewards from previous interactions. Our experiments show that in the 2-action pure coordination game, our system will stabilize to a clustering state where all relationships in the network are rewarded with the optimal payoff. Our experiments also reveal additional interesting patterns in the network.

Biodegradation of spilled diesel fuel in agricultural soil: effect of humates, zeolite, and bioaugmentation.

PubMed

Kuráň, Pavel; Trögl, Josef; Nováková, Jana; Pilařová, Věra; Dáňová, Petra; Pavlorková, Jana; Kozler, Josef; Novák, František; Popelka, Jan

2014-01-01

Possible enhancement of biodegradation of petroleum hydrocarbons in agricultural soil after tank truck accident (~5000 mg/kg dry soil initial concentration) by bioaugmentation of diesel degrading Pseudomonas fluorescens strain and addition of abiotic additives (humates, zeolite) was studied in a 9-month pot experiment. The biodegradation process was followed by means of analytical parameters (hydrocarbon index expressed as content of C10-C40 aliphatic hydrocarbons, ratio pristane/C17, and total organic carbon content) and characterization of soil microbial community (content of phospholipid fatty acids (PLFA) as an indicator of living microbial biomass, respiration, and dehydrogenase activity). The concentration of petroleum hydrocarbons (C10-C40) was successfully reduced by ~60% in all 15 experiment variants. The bioaugmentation resulted in faster hydrocarbon elimination. On the contrary, the addition of humates and zeolite caused only a negligible increase in the degradation rate. These factors, however, affected significantly the amount of PLFA. The humates caused significantly faster increase of the total PLFA suggesting improvement of the soil microenvironment. Zeolite caused significantly slower increase of the total PLFA; nevertheless it aided in homogenization of the soil. Comparison of microbial activities and total PLFA revealed that only a small fraction of autochthonous microbes took part in the biodegradation which confirms that bioaugmentation was the most important treatment.

Effects of Energetic and Inert Nano Particles on Burning Liquid Ethanol Droplets

NASA Astrophysics Data System (ADS)

Plascencia, Miguel; Sim, Hyung Sub; Vargas, Andres; Smith, Owen; Karagozian, Ann

2017-11-01

This study explores the effects of nano particulate additives on ethanol fuel droplet combustion in a quiescent environment. Two different types of droplet combustion experiments were performed: one involving the classic single droplet suspended from a quartz fiber and the other involving a burning droplet that has continual fuel delivery via a quartz capillary. Two alternative nano particles were explored here to demonstrate the effect of energetic additives: reactive nano aluminum (nAl) and inert nano silicon dioxide (nSiO2), each with average diameter 80 nm. Simultaneous high speed visible and OH* chemiluminescence images were taken to determine burning rate constants (K) and to study flame and droplet characteristics with varying particulate concentrations. Particle/vapor ejections were seen in continuously fed droplet experiments, while rod-suspended burning droplets showed limited particle ejection. The nSiO2 -laden, rod-suspended droplets formed a porous, shell-like structure resembling the shape of a droplet at higher nSiO2 concentrations, in contrast to smaller residue structures for nAl-laden droplets. Changes in K depended on concentrations of nAl and nSiO2 as well as the method of droplet formation, and TEM images of particle residue revealed additional insights. Supported by AFOSR Grant FA9550-15-1-0339.

Inorganic phosphorus and nitrogen modify composition and diversity of microbial communities in water of mesotrophic lake.

PubMed

Chróst, Ryszard J; Adamczewski, Tomasz; Kalinowska, Krystyna; Skowrońska, Agnieszka

2009-01-01

The effects of inorganic nutrients (N, P) enrichment of mesotrophic lake water on changes in bacterial and protistan (heterotrophic nanoflagellates and ciliates) communities compositions were studied in the mesocosm experiment. Phosphorus (PO4(3-)) and nitrogen (NH4+) alone and in combination were added to three types of experimental mesocosms. Mesocosms results suggested that simultaneous addition of P and N stimulated phytoplankton growth and production rates of bacterial biomass its turnover rate. Strong positive correlations between chlorophyll a and bacterial secondary production rates suggested that bacteria were mainly controlled by organic substrates released in course ofphytoplankton photosynthesis. Both nutrients increased distinctly protistan biomass and resulted in the shift in ciliate community composition from algivorous to large omnivorous species. The response of bacterial numbers and biomass to nutrients addition was less evident. However, intensive grazing caused their dynamic changes. Fluorescence in situ hybridization (FISH) revealed only small changes in bacterial taxonomic composition. There was an apparent shift in dominance from Cytophaga-Flavobacterium to the Alphaproteobacteria group in the mesocosm with simultaneous addition of P and N, which positively related to increased abundance of bacterivorous protists. Experiment demonstrated that inorganic N and P nutrients directly influenced the bottom-down control of microbial communities, which had a crucial effect on morphological diversity of bacteria.

Structure and regulation of the Yersinia pestis yscBCDEF operon.

PubMed Central

Haddix, P L; Straley, S C

1992-01-01

We have investigated the physical and genetic structure and regulation of the Yersinia pestis yscBCDEF region, previously called lcrC. DNA sequence analysis showed that this region is homologous to the corresponding part of the ysc locus of Yersinia enterocolitica and suggested that the yscBCDEF cistrons belong to a single operon on the low-calcium response virulence plasmid pCD1. Promoter activity measurements of ysc subclones indicated that yscBCDEF constitutes a suboperon of the larger ysc region by revealing promoter activity in a clone containing the 3' end of yscD, intact yscE and yscF, and part of yscG. These experiments also revealed an additional weak promoter upstream of yscD. Northern (RNA) analysis with a yscD probe showed that operon transcription is thermally induced and downregulated in the presence of Ca2+. Primer extension of operon transcripts suggested that two promoters, a moderate-level constitutive one and a stronger, calcium-downregulated one, control full-length operon transcription at 37 degrees C. Primer extension provided additional support for the proposed designation of a yscBCDEF suboperon by identifying a 5' end within yscF, for which relative abundances in the presence and absence of Ca2+ revealed regulation that is distinct from that for transcripts initiating farther upstream. YscB and YscC were expressed in Escherichia coli by using a high-level transcription system. Attempts to express YscD were only partially successful, but they revealed interesting regulation at the translational level. Images PMID:1624469

Na+/substrate Coupling in the Multidrug Antiporter NorM Probed with a Spin-labeled Substrate

PubMed Central

Steed, P. Ryan; Stein, Richard A.; Mishra, Smriti; Goodman, Michael C.; Mchaourab, Hassane S.

2013-01-01

NorM of the multidrug and toxic compound extrusion (MATE) family of transporters couples the efflux of a broad range of hydrophobic molecules to an inward Na+ gradient across the cell membrane. Several crystal structures of MATE transporters revealed distinct substrate binding sites leading to differing models of the mechanism of ion-coupled substrate extrusion. In the experiments reported here, we observed that a spin-labeled derivative of daunorubicin, Ruboxyl, is transported by NorM from Vibrio cholerae. It is therefore ideal to characterize mechanistically relevant binding interactions with NorM and to directly address the coupling of ion and drug binding. Fluorescence and EPR experiments revealed that Ruboxyl binds to NorM with micromolar affinity and becomes immobilized upon binding, even in the presence of Na+. Using double electron-electron resonance (DEER) spectroscopy, we determined that Ruboxyl binds to a single site on the periplasmic side of the protein. The presence of Na+ did not translocate the substrate to a second site as previously proposed. These experiments surprisingly show that Na+ does not affect the affinity or location of the substrate binding site on detergent-solubilized NorM, thus suggesting that additional factors beyond simple mutual exclusivity of binding, such as the presence of a Na+ gradient across the native membrane, govern Na+/drug coupling during antiport. PMID:23902581

Defense Mechanisms of Empathetic Players in the Spatial Ultimatum Game

NASA Astrophysics Data System (ADS)

Szolnoki, Attila; Perc, Matjaž; Szabó, György

2012-08-01

Experiments on the ultimatum game have revealed that humans are remarkably fond of fair play. When asked to share an amount of money, unfair offers are rare and their acceptance rate small. While empathy and spatiality may lead to the evolution of fairness, thus far considered continuous strategies have precluded the observation of solutions that would be driven by pattern formation. Here we introduce a spatial ultimatum game with discrete strategies, and we show that this simple alteration opens the gate to fascinatingly rich dynamical behavior. In addition to mixed stationary states, we report the occurrence of traveling waves and cyclic dominance, where one strategy in the cycle can be an alliance of two strategies. The highly webbed phase diagram, entailing continuous and discontinuous phase transitions, reveals hidden complexity in the pursuit of human fair play.

Colour Cues That Are Not Directly Attached to the Body of Males Do Not Influence the Mate Choice of Zebra Finches.

PubMed

Krause, E Tobias

2016-01-01

Mate choice decisions of female zebra finches are generally thought to rely on the assessment of male quality, which includes the specific ornamentation of males. A commonly used paradigm to experimentally manipulate a male's attractiveness is to add a coloured leg ring to the bird. Some studies have shown that female zebra finches prefer or alter their investment in males that have an additional red leg ring compared with males with green leg rings. Whether the coloured artificial ornaments need to be attached to the male's body or whether environmental colouration could have a similar effect on male attractiveness remains unclear. Here, I investigated this novel context to determine whether female choice between males is affected by environmental colour cues that are not directly attached to the male's body in four experiments involving 220 zebra finches (Taeniopygia guttata). A first experiment revealed that females chose males with red colour cues in the environmental background over males with green cues in the background. Based on this finding, I conducted follow-up experiments to obtain a deeper understanding of how environmental colour cues affect mate choice. Therefore, I examined whether female choice behaviour or male behaviour was altered in two additional experiments. Both experiments failed to show any effects of environmental colour cues on female choice or on male behaviour. Therefore, I replicated the initial experiment in a fourth experiment. Again replication failed; thus, the initial results indicating that environmental colouration affects mate choice behaviour of female zebra finches were not supported by the three subsequent experiments; thus, the outcome of the first experiment seems to be a false positive. Taking my results together, I found no robust support for the idea that environmental colour cues that are not directly attached to the body of male zebra finches affect female mate choice decisions.

The Impact of Specific and Complex Trauma on the Mental Health of Homeless Youth.

PubMed

Wong, Carolyn F; Clark, Leslie F; Marlotte, Lauren

2016-03-01

This study investigates the relative impact of trauma experiences that occurred prior to and since becoming homeless on depressive symptoms, posttraumatic stress disorder (PTSD) symptoms, and self-injurious behaviors among a sample of homeless youth (N = 389). Youth (aged 13 to 25) who had been homeless or precariously housed in the past year completed a survey about housing history, experiences of violence and victimization, mental health, and service utilization. In addition to examining the impact associated with specific trauma types, we also considered the effect of "early-on" poly-victimization (i.e., cumulative number of reported traumas prior to homelessness) and the influence of a compound sexual trauma variable created to represent earlier complex trauma. This created-variable has values ranging from no reported trauma, single trauma, multiple non-sexual traumas, and multiple traumas that co-occurred with sexual abuse. Multivariate analyses revealed that specific traumatic experiences prior to homelessness, including sexual abuse, emotional abuse/neglect, and adverse home environment, predicted greater mental health symptoms. Poly-victimization did not add to the prediction of mental health symptoms after the inclusion of specific traumas. Results with early compound sexual trauma revealed significant differences between lower-order trauma exposures and multiple-trauma exposures. Specifically, experience of multiple traumas that co-occurred with sexual trauma was significantly more detrimental in predicting PTSD symptoms than multiple traumas of non-sexual nature. Findings support the utility of an alternate/novel conceptualization of complex trauma, and support the need to carefully evaluate complex traumatic experiences that occurred prior to homelessness, which can impact the design and implementation of mental health care and services for homeless youth. © The Author(s) 2014.

Rheumatoid arthritis patients' experiences of wearing therapeutic footwear - A qualitative investigation

PubMed Central

Williams, Anita E; Nester, Christopher J; Ravey, Michael I

2007-01-01

Background Specialist 'therapeutic' footwear is recommended for patients with diseases such as rheumatoid arthritis (RA) as a beneficial intervention for reducing foot pain, improving foot health, and increasing general mobility. However, many patients choose not to wear this footwear. Recommendations from previous studies have been implemented but have had little impact in improving this situation. The aim of this study was to explore RA patients' experiences of this footwear to ascertain the factors which influence their choice to wear it or not. Method Ten females and three males with RA and experience of wearing specialist footwear were recruited from four National Health Service orthotic services. Semi-structured interviews were carried out in the participants own homes. A hermeneutic phenomenological analysis of the transcripts was carried out to identify themes. Results The analysis revealed two main themes from both the female and male groups. These were the participants' feelings about their footwear and their experiences of the practitioner/s involved in providing the footwear. In addition, further themes were revealed from the female participants. These were feelings about their feet, behaviour associated with the footwear, and their feelings about what would have improved their experience. Conclusion Unlike any other intervention specialist therapeutic footwear replaces something that is normally worn and is part of an individual's body image. It has much more of a negative impact on the female patients' emotions and activities than previously acknowledged and this influences their behaviour with it. The patients' consultations with the referring and dispensing practitioners are pivotal moments within the patient/practitioner relationship that have the potential to influence whether patients choose to wear the footwear or not. PMID:17976235

Using imagination to understand the neural basis of episodic memory.

PubMed

Hassabis, Demis; Kumaran, Dharshan; Maguire, Eleanor A

2007-12-26

Functional MRI (fMRI) studies investigating the neural basis of episodic memory recall, and the related task of thinking about plausible personal future events, have revealed a consistent network of associated brain regions. Surprisingly little, however, is understood about the contributions individual brain areas make to the overall recollective experience. To examine this, we used a novel fMRI paradigm in which subjects had to imagine fictitious experiences. In contrast to future thinking, this results in experiences that are not explicitly temporal in nature or as reliant on self-processing. By using previously imagined fictitious experiences as a comparison for episodic memories, we identified the neural basis of a key process engaged in common, namely scene construction, involving the generation, maintenance and visualization of complex spatial contexts. This was associated with activations in a distributed network, including hippocampus, parahippocampal gyrus, and retrosplenial cortex. Importantly, we disambiguated these common effects from episodic memory-specific responses in anterior medial prefrontal cortex, posterior cingulate cortex and precuneus. These latter regions may support self-schema and familiarity processes, and contribute to the brain's ability to distinguish real from imaginary memories. We conclude that scene construction constitutes a common process underlying episodic memory and imagination of fictitious experiences, and suggest it may partially account for the similar brain networks implicated in navigation, episodic future thinking, and the default mode. We suggest that additional brain regions are co-opted into this core network in a task-specific manner to support functions such as episodic memory that may have additional requirements.

Social Anxiety among Chinese People

PubMed Central

Fan, Qianqian; Chang, Weining C.

2015-01-01

The experience of social anxiety has largely been investigated among Western populations; much less is known about social anxiety in other cultures. Unlike the Western culture, the Chinese emphasize interdependence and harmony with social others. In addition, it is unclear if Western constructed instruments adequately capture culturally conditioned conceptualizations and manifestations of social anxiety that might be specific to the Chinese. The present study employed a sequence of qualitative and quantitative approaches to examine the assessment of social anxiety among the Chinese people. Interviews and focus group discussions with Chinese participants revealed that some items containing the experience of social anxiety among the Chinese are not present in existing Western measures. Factor analysis was employed to examine the factor structure of the more comprehensive scale. This approach revealed an “other concerned anxiety” factor that appears to be specific to the Chinese. Subsequent analysis found that the new factor—other concerned anxiety—functioned the same as other social anxiety factors in their association with risk factors of social anxiety, such as attachment, parenting, behavioral inhibition/activation, and attitude toward group. The implications of these findings for a more culturally sensitive assessment tool of social anxiety among the Chinese were discussed. PMID:26380367

Antitumor effects of Marginisporum crassissimum (Rhodophyceae), a marine red alga.

PubMed

Hiroishi, S; Sugie, K; Yoshida, T; Morimoto, J; Taniguchi, Y; Imai, S; Kurebayashi, J

2001-06-26

Marginisporum crassissimum (Yendo) Ganesan, a marine red alga found in the ordinal coastal sea around Japan, revealed antitumor (antimetastatic) effects in vitro and in vivo. In in vitro experiments, extracts of this alga inhibited not only the growth of several tumor cell lines, such as B16-BL6 (a mouse melanoma cell line), JYG-B (a mouse mammary carcinoma cell line) and KPL-1 (a human mammary carcinoma cell line), but also invasion of B16-BL6 cells in a culture system. In in vivo experiments, the lung metastasis of B16-BL6 cells inoculated to the tail vein of B57BL/6J mice was inhibited by intraperitoneal administration of an extract from the alga. In addition, life prolongation of B57BL/6J mice inoculated with B16-BL6 cells was also observed by the intraperitoneal administration of the extract. An effective substance showing B16-BL6 growth inhibition in vitro was partially purified by filtration and hydrophobic column chromatography, and was revealed to be sensitive to trypsin-digestion and heat-treatment. The molecular weight of the substance was greater than 100 kDa. This is the first study demonstrating antitumor (antimetastatic) effects of M. crassissimum.

Segmentation precedes face categorization under suboptimal conditions.

PubMed

Van Den Boomen, Carlijn; Fahrenfort, Johannes J; Snijders, Tineke M; Kemner, Chantal

2015-01-01

Both categorization and segmentation processes play a crucial role in face perception. However, the functional relation between these subprocesses is currently unclear. The present study investigates the temporal relation between segmentation-related and category-selective responses in the brain, using electroencephalography (EEG). Surface segmentation and category content were both manipulated using texture-defined objects, including faces. This allowed us to study brain activity related to segmentation and to categorization. In the main experiment, participants viewed texture-defined objects for a duration of 800 ms. EEG results revealed that segmentation-related responses precede category-selective responses. Three additional experiments revealed that the presence and timing of categorization depends on stimulus properties and presentation duration. Photographic objects were presented for a long and short (92 ms) duration and evoked fast category-selective responses in both cases. On the other hand, presentation of texture-defined objects for a short duration only evoked segmentation-related but no category-selective responses. Category-selective responses were much slower when evoked by texture-defined than by photographic objects. We suggest that in case of categorization of objects under suboptimal conditions, such as when low-level stimulus properties are not sufficient for fast object categorization, segmentation facilitates the slower categorization process.

Segmentation precedes face categorization under suboptimal conditions

PubMed Central

Van Den Boomen, Carlijn; Fahrenfort, Johannes J.; Snijders, Tineke M.; Kemner, Chantal

2015-01-01

Both categorization and segmentation processes play a crucial role in face perception. However, the functional relation between these subprocesses is currently unclear. The present study investigates the temporal relation between segmentation-related and category-selective responses in the brain, using electroencephalography (EEG). Surface segmentation and category content were both manipulated using texture-defined objects, including faces. This allowed us to study brain activity related to segmentation and to categorization. In the main experiment, participants viewed texture-defined objects for a duration of 800 ms. EEG results revealed that segmentation-related responses precede category-selective responses. Three additional experiments revealed that the presence and timing of categorization depends on stimulus properties and presentation duration. Photographic objects were presented for a long and short (92 ms) duration and evoked fast category-selective responses in both cases. On the other hand, presentation of texture-defined objects for a short duration only evoked segmentation-related but no category-selective responses. Category-selective responses were much slower when evoked by texture-defined than by photographic objects. We suggest that in case of categorization of objects under suboptimal conditions, such as when low-level stimulus properties are not sufficient for fast object categorization, segmentation facilitates the slower categorization process. PMID:26074838

Health circles for teleworkers: selective results on stress, strain and coping styles.

PubMed

Konradt, U; Schmook, R; Wilm, A; Hertel, G

2000-06-01

Telework is decentralized computer-mediated performance of work activities at a location distant from the employing organization. In order to improve well-being at such remote workplaces, we developed a health circle (HC) concept for teleworkers. Three HC sessions were conducted with a total of 17 teleworkers from diverse organizations and branches. The sessions were moderated by a professional facilitator, while the participants selected the discussion issues. Typical issues were technical problems at the home-based computer, time management, communication with supervisors, colleagues and customers, and feelings of isolation from the main company. Besides discussing these stress factors, participants developed concrete coping strategies based on the exchange of experiences and additional informational input by external experts. Process evaluation at the end of each meeting revealed that participants found the exchange of personal experiences and the informational input during the HCs very helpful, as well as the common development of coping strategies. Moreover, a questionnaire 2 months after the last HC session revealed that participants reported significantly more positive changes in typical stress factors than teleworkers in a control group. The implications of these results for preventive and corrective strategies of telework design are discussed.

Experimental saltwater intrusion in coastal aquifers using automated image analysis: Applications to homogeneous aquifers

NASA Astrophysics Data System (ADS)

Robinson, G.; Ahmed, Ashraf A.; Hamill, G. A.

2016-07-01

This paper presents the applications of a novel methodology to quantify saltwater intrusion parameters in laboratory-scale experiments. The methodology uses an automated image analysis procedure, minimising manual inputs and the subsequent systematic errors that can be introduced. This allowed the quantification of the width of the mixing zone which is difficult to measure in experimental methods that are based on visual observations. Glass beads of different grain sizes were tested for both steady-state and transient conditions. The transient results showed good correlation between experimental and numerical intrusion rates. The experimental intrusion rates revealed that the saltwater wedge reached a steady state condition sooner while receding than advancing. The hydrodynamics of the experimental mixing zone exhibited similar traits; a greater increase in the width of the mixing zone was observed in the receding saltwater wedge, which indicates faster fluid velocities and higher dispersion. The angle of intrusion analysis revealed the formation of a volume of diluted saltwater at the toe position when the saltwater wedge is prompted to recede. In addition, results of different physical repeats of the experiment produced an average coefficient of variation less than 0.18 of the measured toe length and width of the mixing zone.

Social Anxiety among Chinese People.

PubMed

Fan, Qianqian; Chang, Weining C

2015-01-01

The experience of social anxiety has largely been investigated among Western populations; much less is known about social anxiety in other cultures. Unlike the Western culture, the Chinese emphasize interdependence and harmony with social others. In addition, it is unclear if Western constructed instruments adequately capture culturally conditioned conceptualizations and manifestations of social anxiety that might be specific to the Chinese. The present study employed a sequence of qualitative and quantitative approaches to examine the assessment of social anxiety among the Chinese people. Interviews and focus group discussions with Chinese participants revealed that some items containing the experience of social anxiety among the Chinese are not present in existing Western measures. Factor analysis was employed to examine the factor structure of the more comprehensive scale. This approach revealed an "other concerned anxiety" factor that appears to be specific to the Chinese. Subsequent analysis found that the new factor-other concerned anxiety-functioned the same as other social anxiety factors in their association with risk factors of social anxiety, such as attachment, parenting, behavioral inhibition/activation, and attitude toward group. The implications of these findings for a more culturally sensitive assessment tool of social anxiety among the Chinese were discussed.

Examination of the Teaching Styles of Nursing Professional Development Specialists, Part II: Correlational Study on Teaching Styles and Use of Adult Learning Theory.

PubMed

Curran, Mary K

2014-07-16

This article, the second in a two-part series, details a correlational study that examined the effects of four variables (graduate degrees in nursing education, professional development training in adult learning theory, nursing professional development [NPD] certification, and NPD specialist experience) on the use of adult learning theory to guide curriculum development. Using the Principles of Adult Learning Scale, 114 NPD specialists tested the hypothesis that NPD specialists with graduate degrees in nursing education, professional development training in adult learning theory, NPD certification, and NPD experience would use higher levels of adult learning theory in their teaching practices to guide curriculum development than those without these attributes. This hypothesis was rejected as regression analysis revealed only one statistically significant predictor variable, NPD certification, influenced the use of adult learning theory. In addition, analysis revealed NPD specialists tended to support a teacher-centered rather than a learner-centered teaching style, indicating NPD educators are not using adult learning theory to guide teaching practices and curriculum development. J Contin Educ Nurs. 2014;45(8):xxx-xxx. Copyright 2014, SLACK Incorporated.

Dual embryonic origin and patterning of the pharyngeal skeleton in the axolotl (Ambystoma mexicanum).

PubMed

Sefton, Elizabeth M; Piekarski, Nadine; Hanken, James

2015-01-01

The impressive morphological diversification of vertebrates was achieved in part by innovation and modification of the pharyngeal skeleton. Extensive fate mapping in amniote models has revealed a primarily cranial neural crest derivation of the pharyngeal skeleton. Although comparable fate maps of amphibians produced over several decades have failed to document a neural crest derivation of ventromedial elements in these vertebrates, a recent report provides evidence of a mesodermal origin of one of these elements, basibranchial 2, in the axolotl. We used a transgenic labeling protocol and grafts of labeled cells between GFP+ and white embryos to derive a fate map that describes contributions of both cranial neural crest and mesoderm to the axolotl pharyngeal skeleton, and we conducted additional experiments that probe the mechanisms that underlie mesodermal patterning. Our fate map confirms a dual embryonic origin of the pharyngeal skeleton in urodeles, including derivation of basibranchial 2 from mesoderm closely associated with the second heart field. Additionally, heterotopic transplantation experiments reveal lineage restriction of mesodermal cells that contribute to pharyngeal cartilage. The mesoderm-derived component of the pharyngeal skeleton appears to be particularly sensitive to retinoic acid (RA): administration of exogenous RA leads to loss of the second basibranchial, but not the first. Neural crest was undoubtedly critical in the evolution of the vertebrate pharyngeal skeleton, but mesoderm may have played a central role in forming ventromedial elements, in particular. When and how many times during vertebrate phylogeny a mesodermal contribution to the pharyngeal skeleton evolved remain to be resolved. © 2015 Wiley Periodicals, Inc.

CO Metabolism in the Acetogen Acetobacterium woodii

PubMed Central

Bertsch, Johannes

2015-01-01

The Wood-Ljungdahl pathway allows acetogenic bacteria to grow on a number of one-carbon substrates, such as carbon dioxide, formate, methyl groups, or even carbon monoxide. Since carbon monoxide alone or in combination with hydrogen and carbon dioxide (synthesis gas) is an increasingly important feedstock for third-generation biotechnology, we studied CO metabolism in the model acetogen Acetobacterium woodii. When cells grew on H2-CO2, addition of 5 to 15% CO led to higher final optical densities, indicating the utilization of CO as a cosubstrate. However, the growth rate was decreased by the presence of small amounts of CO, which correlated with an inhibition of H2 consumption. Experiments with resting cells revealed that the degree of inhibition of H2 consumption was a function of the CO concentration. Since the hydrogen-dependent CO2 reductase (HDCR) of A. woodii is known to be very sensitive to CO, we speculated that cells may be more tolerant toward CO when growing on formate, the product of the HDCR reaction. Indeed, addition of up to 25% CO did not influence growth rates on formate, while the final optical densities and the production of acetate increased. Higher concentrations (75 and 100%) led to a slight inhibition of growth and to decreasing rates of formate and CO consumption. Experiments with resting cells revealed that the HDCR is a site of CO inhibition. In contrast, A. woodii was not able to grow on CO as a sole carbon and energy source, and growth on fructose-CO or methanol-CO was not observed. PMID:26092462

Allosteric regulation of focal adhesion kinase by PIP₂ and ATP.

PubMed

Zhou, Jing; Bronowska, Agnieszka; Le Coq, Johanne; Lietha, Daniel; Gräter, Frauke

2015-02-03

Focal adhesion kinase (FAK) is a nonreceptor tyrosine kinase that regulates cell signaling, proliferation, migration, and development. A major mechanism of regulation of FAK activity is an intramolecular autoinhibitory interaction between two of its domains--the catalytic and FERM domains. Upon cell adhesion to the extracellular matrix, FAK is being translocated toward focal adhesion sites and activated. Interactions of FAK with phosphoinositide phosphatidylinsositol-4,5-bis-phosphate (PIP₂) are required to activate FAK. However, the molecular mechanism of the activation remains poorly understood. Recent fluorescence resonance energy transfer experiments revealed a closure of the FERM-kinase interface upon ATP binding, which is reversed upon additional binding of PIP₂. Here, we addressed the allosteric regulation of FAK by performing all-atom molecular-dynamics simulations of a FAK fragment containing the catalytic and FERM domains, and comparing the dynamics in the absence or presence of ATP and PIP₂. As a major conformational change, we observe a closing and opening motion upon ATP and additional PIP₂ binding, respectively, in good agreement with the fluorescence resonance energy transfer experiments. To reveal how the binding of the regulatory PIP₂ to the FERM F2 lobe is transduced to the very distant F1/N-lobe interface, we employed force distribution analysis. We identified a network of mainly charged residue-residue interactions spanning from the PIP₂ binding site to the distant interface between the kinase and FERM domains, comprising candidate residues for mutagenesis to validate the predicted mechanism of FAK activation. Copyright © 2015 Biophysical Society. Published by Elsevier Inc. All rights reserved.

Integrative Genomics Reveals Novel Molecular Pathways and Gene Networks for Coronary Artery Disease

PubMed Central

Mäkinen, Ville-Petteri; Civelek, Mete; Meng, Qingying; Zhang, Bin; Zhu, Jun; Levian, Candace; Huan, Tianxiao; Segrè, Ayellet V.; Ghosh, Sujoy; Vivar, Juan; Nikpay, Majid; Stewart, Alexandre F. R.; Nelson, Christopher P.; Willenborg, Christina; Erdmann, Jeanette; Blakenberg, Stefan; O'Donnell, Christopher J.; März, Winfried; Laaksonen, Reijo; Epstein, Stephen E.; Kathiresan, Sekar; Shah, Svati H.; Hazen, Stanley L.; Reilly, Muredach P.; Lusis, Aldons J.; Samani, Nilesh J.; Schunkert, Heribert; Quertermous, Thomas; McPherson, Ruth; Yang, Xia; Assimes, Themistocles L.

2014-01-01

The majority of the heritability of coronary artery disease (CAD) remains unexplained, despite recent successes of genome-wide association studies (GWAS) in identifying novel susceptibility loci. Integrating functional genomic data from a variety of sources with a large-scale meta-analysis of CAD GWAS may facilitate the identification of novel biological processes and genes involved in CAD, as well as clarify the causal relationships of established processes. Towards this end, we integrated 14 GWAS from the CARDIoGRAM Consortium and two additional GWAS from the Ottawa Heart Institute (25,491 cases and 66,819 controls) with 1) genetics of gene expression studies of CAD-relevant tissues in humans, 2) metabolic and signaling pathways from public databases, and 3) data-driven, tissue-specific gene networks from a multitude of human and mouse experiments. We not only detected CAD-associated gene networks of lipid metabolism, coagulation, immunity, and additional networks with no clear functional annotation, but also revealed key driver genes for each CAD network based on the topology of the gene regulatory networks. In particular, we found a gene network involved in antigen processing to be strongly associated with CAD. The key driver genes of this network included glyoxalase I (GLO1) and peptidylprolyl isomerase I (PPIL1), which we verified as regulatory by siRNA experiments in human aortic endothelial cells. Our results suggest genetic influences on a diverse set of both known and novel biological processes that contribute to CAD risk. The key driver genes for these networks highlight potential novel targets for further mechanistic studies and therapeutic interventions. PMID:25033284

An exploratory study of the experience of fibromyalgia diagnosis in South Africa.

PubMed

Cooper, Silvie; Gilbert, Leah

2017-05-01

Within the conceptual framework of 'medically-ill-defined' conditions, this article focuses on the experiences of 'diagnosis' through a narrative analysis of fibromyalgia (a chronic musculoskeletal pain disorder) in South Africa. In-depth interviews were used to collect narratives from 15 participants. The findings show how the contested and confusing experience of fibromyalgia diagnosis can be understood, by viewing the interactions that patients have with their practitioners, families, peers and colleagues. The currency of fibromyalgia as a diagnosis and the inequalities present in the South African health care system characterise the experiences of symptom recognition, diagnosis and treatment. The analysis reveals how those living with fibromyalgia search for diagnosis, and struggle to maintain legitimacy for their experience in the complex constellation of porous symptoms that appear infrequently. The findings of this study confirm the existing evidence that shows fibromyalgia to be a challenging illness experience, which is attributed to the lack of clarity and legitimacy, and high contestation that surrounds the condition. Additionally, this study presents the ways that limited access to diagnosis and treatment for fibromyalgia in the South African context shapes this specific illness experience, and the value of using narrative approaches to gain insight into how people live with hidden and poorly understood conditions in this environment.

Understanding Biases in Ribosome Profiling Experiments Reveals Signatures of Translation Dynamics in Yeast.

PubMed

Hussmann, Jeffrey A; Patchett, Stephanie; Johnson, Arlen; Sawyer, Sara; Press, William H

2015-12-01

Ribosome profiling produces snapshots of the locations of actively translating ribosomes on messenger RNAs. These snapshots can be used to make inferences about translation dynamics. Recent ribosome profiling studies in yeast, however, have reached contradictory conclusions regarding the average translation rate of each codon. Some experiments have used cycloheximide (CHX) to stabilize ribosomes before measuring their positions, and these studies all counterintuitively report a weak negative correlation between the translation rate of a codon and the abundance of its cognate tRNA. In contrast, some experiments performed without CHX report strong positive correlations. To explain this contradiction, we identify unexpected patterns in ribosome density downstream of each type of codon in experiments that use CHX. These patterns are evidence that elongation continues to occur in the presence of CHX but with dramatically altered codon-specific elongation rates. The measured positions of ribosomes in these experiments therefore do not reflect the amounts of time ribosomes spend at each position in vivo. These results suggest that conclusions from experiments in yeast using CHX may need reexamination. In particular, we show that in all such experiments, codons decoded by less abundant tRNAs were in fact being translated more slowly before the addition of CHX disrupted these dynamics.

Understanding Biases in Ribosome Profiling Experiments Reveals Signatures of Translation Dynamics in Yeast

PubMed Central

Hussmann, Jeffrey A.; Patchett, Stephanie; Johnson, Arlen; Sawyer, Sara; Press, William H.

2015-01-01

Ribosome profiling produces snapshots of the locations of actively translating ribosomes on messenger RNAs. These snapshots can be used to make inferences about translation dynamics. Recent ribosome profiling studies in yeast, however, have reached contradictory conclusions regarding the average translation rate of each codon. Some experiments have used cycloheximide (CHX) to stabilize ribosomes before measuring their positions, and these studies all counterintuitively report a weak negative correlation between the translation rate of a codon and the abundance of its cognate tRNA. In contrast, some experiments performed without CHX report strong positive correlations. To explain this contradiction, we identify unexpected patterns in ribosome density downstream of each type of codon in experiments that use CHX. These patterns are evidence that elongation continues to occur in the presence of CHX but with dramatically altered codon-specific elongation rates. The measured positions of ribosomes in these experiments therefore do not reflect the amounts of time ribosomes spend at each position in vivo. These results suggest that conclusions from experiments in yeast using CHX may need reexamination. In particular, we show that in all such experiments, codons decoded by less abundant tRNAs were in fact being translated more slowly before the addition of CHX disrupted these dynamics. PMID:26656907

Study of the cross-reactivity of fish allergens based on a questionnaire and blood testing.

PubMed

Kobayashi, Yukihiro; Huge, Jiletu; Imamura, Shintaro; Hamada-Sato, Naoko

2016-07-01

Parvalbumin and collagen have been identified as cross-reactive allergens for fish allergies. Although doctors realize that various fish elicit allergies, the targets of food allergen labeling laws were only mackerels and salmons in Japan and mackerels in South Korea. This study aimed to reveal the causative species for fish allergy via questionnaires and blood tests. Questionnaire research was conducted in Japan via the internet concerning allergies for fish-allergic patients or their family members. Next, IgE reactivities and cross-reactivities of 26 fish species were analyzed using sera obtained from 16 Japanese patients who were allergic to fish parvalbumin or collagen by enzyme-linked immunosorbent assay (ELISA) and inhibition ELISA. Questionnaire research revealed that 88% patients cannot eat mackerel and salmon in addition to other fish. In addition, 85% respondents were not satisfied with the current food allergen labeling law. In ELISA analyses, we clarified that pooled serum obtained from patients with fish parvalbumin-specific allergies exhibited IgE reactivity to the extracts of most fish species, and pooled serum obtained from patients with fish collagen-specific allergies displayed IgE reactivity to the extracts of all types of fish. Inhibition ELISA experiments revealed cross-reactivities of parvalbumin or collagen to extracts from all fish tested. Most patients with fish allergies displayed allergic symptoms following the intake of various fish species. In addition, fish parvalbumin and collagen were causative factors of fish allergy and were highly cross-reactive fish panallergens. Therefore, current laws should be revised in Japan and South Korea. Copyright © 2016 Japanese Society of Allergology. Production and hosting by Elsevier B.V. All rights reserved.

Pushing typists back on the learning curve: revealing chunking in skilled typewriting.

PubMed

Yamaguchi, Motonori; Logan, Gordon D

2014-04-01

Theories of skilled performance propose that highly trained skills involve hierarchically structured control processes. The present study examined and demonstrated hierarchical control at several levels of processing in skilled typewriting. In the first two experiments, we scrambled the order of letters in words to prevent skilled typists from chunking letters, and compared typing words and scrambled words. Experiment 1 manipulated stimulus quality to reveal chunking in perception, and Experiment 2 manipulated concurrent memory load to reveal chunking in short-term memory (STM). Both experiments manipulated the number of letters in words and nonwords to reveal chunking in motor planning. In the next two experiments, we degraded typing skill by altering the usual haptic feedback by using a laser-projection keyboard, so that typists had to monitor keystrokes. Neither the number of motor chunks (Experiment 3) nor the number of STM items (Experiment 4) was influenced by the manipulation. The results indicate that the utilization of hierarchical control depends on whether the input allows chunking but not on whether the output is generated automatically. We consider the role of automaticity in hierarchical control of skilled performance.

Numerical Investigation of Plasma Detachment in Magnetic Nozzle Experiments

NASA Technical Reports Server (NTRS)

Sankaran, Kamesh; Polzin, Kurt A.

2008-01-01

At present there exists no generally accepted theoretical model that provides a consistent physical explanation of plasma detachment from an externally-imposed magnetic nozzle. To make progress towards that end, simulation of plasma flow in the magnetic nozzle of an arcjet experiment is performed using a multidimensional numerical simulation tool that includes theoretical models of the various dispersive and dissipative processes present in the plasma. This is an extension of the simulation tool employed in previous work by Sankaran et al. The aim is to compare the computational results with various proposed magnetic nozzle detachment theories to develop an understanding of the physical mechanisms that cause detachment. An applied magnetic field topology is obtained using a magnetostatic field solver (see Fig. I), and this field is superimposed on the time-dependent magnetic field induced in the plasma to provide a self-consistent field description. The applied magnetic field and model geometry match those found in experiments by Kuriki and Okada. This geometry is modeled because there is a substantial amount of experimental data that can be compared to the computational results, allowing for validation of the model. In addition, comparison of the simulation results with the experimentally obtained plasma parameters will provide insight into the mechanisms that lead to plasma detachment, revealing how they scale with different input parameters. Further studies will focus on modeling literature experiments both for the purpose of additional code validation and to extract physical insight regarding the mechanisms driving detachment.

Effects of dietary salt restriction on renal progression and interstitial fibrosis in adriamycin nephrosis.

PubMed

Park, Joon-Sung; Kim, Sua; Jo, Chor Ho; Oh, Il Hwan; Kim, Gheun-Ho

2014-01-01

Although high salt intake is thought to accelerate renal progression in proteinuric kidney disease, it is not known whether strict dietary salt restriction could delay renal inflammation and interstitial fibrosis. Here, we sought to answer this question in a rat model of adriamycin-induced nephrotic syndrome. Adriamycin was administered via the femoral vein in a single bolus (7.5 mg/kg), and the rats were put on a sodium-deficient rodent diet. Rats with intact kidneys were studied for 5 weeks (experiment 1), and uninephrectomized rats were studied for 6 weeks (experiment 2). In experiment 1, restricting salt intake improved renal tubulointerstitial histopathology in adriamycin-treated rats. Immunohistochemical and immunoblot results additionally showed that restricting dietary salt lowered adriamycin-induced expression of osteopontin, collagen III, and fibronectin. In experiment 2, salt restriction improved adriamycin-induced azotemia, although it did not affect proteinuria or blood pressure. Dietary salt restriction also reduced adriamycin-induced infiltration of ED1-positive cells and the upregulated expression of osteopontin and α-SMA. Masson's trichrome and Sirius red staining revealed that salt restriction slowed Adriamycin-induced progression of renal interstitial fibrosis. Finally, qPCR revealed that adriamycin-induced expression of TNF-α, IκB-α, gp91(phox), p47(phox), and p67(phox) mRNA was blocked by salt restriction. Our findings demonstrate that strict dietary salt restriction delays the progress of renal inflammation and fibrosis in proteinuric kidney disease, most likely via relieving the reactive oxygen species-mediated NF-κB activation. © 2014 S. Karger AG, Basel.

"Watch out!": Effects of instructed threat and avoidance on human free-operant approach-avoidance behavior.

PubMed

Schlund, Michael W; Treacher, Kay; Preston, Oli; Magee, Sandy K; Richman, David M; Brewer, Adam T; Cameron, Gemma; Dymond, Simon

2017-01-01

Approach-avoidance paradigms create a competition between appetitive and aversive contingencies and are widely used in nonhuman research on anxiety. Here, we examined how instructions about threat and avoidance impact control by competing contingencies over human approach-avoidance behavior. Additionally, Experiment 1 examined the effects of threat magnitude (money loss amount) and avoidance cost (fixed ratio requirements), whereas Experiment 2 examined the effects of threat information (available, unavailable and inaccurate) on approach-avoidance. During the task, approach responding was modeled by reinforcing responding with money on a FR schedule. By performing an observing response, participants produced an escalating "threat meter". Instructions stated that the threat meter levels displayed the current probability of losing money, when in fact loss only occurred when the level reached the maximum. Instructions also stated pressing an avoidance button lowered the threat level. Overall, instructions produced cycles of approach and avoidance responding with transitions from approach to avoidance when threat was high and transitions back to approach after avoidance reduced threat. Experiment 1 revealed increasing avoidance cost, but not threat magnitude, shifted approach-avoidance transitions to higher threat levels and increased anxiety ratings, but did not influence the frequency of approach-avoidance cycles. Experiment 2 revealed when threat level information was available or absent earnings were high, but earnings decreased when inaccurate threat information was incompatible with contingencies. Our findings build on prior nonhuman and human approach-avoidance research by highlighting how instructed threat and avoidance can impact human AA behavior and self-reported anxiety. © 2017 Society for the Experimental Analysis of Behavior.

Administrative Stressors and Islamic Coping Strategies Among Muslim Primary Principals in Malaysia: A Mixed Method Study.

PubMed

Tahir, Lokman Mohd; Khan, Aqeel; Musah, Mohammed Borhandden; Ahmad, Roslee; Daud, Khadijah; Al-Hudawi, Shafeeq Hussain Vazhathodi; Musta'Amal, Aede Hatib; Talib, Rohaya

2017-11-18

Principals are school leaders who experienced stress while leading their schools towards excellence. However, principals stress experiences are always ignored and least studied. This mixed-methods study investigates primary principals' stress experiences and their Islamic coping strategies used in incapacitating the stress experiences. A total of 216 Muslim primary principals across different gender, types of schools and years of experiences as school leaders responded to the administrative stress and the Islamic coping strategies items. In addition, seven primary principals were purposefully selected and interviewed in exploring their reasons of using Islamic coping strategies for their relieving process. Results discovered that primary principals experienced fairly stress level and they perceived managing students' academic achievement was the most stressor followed by managing teachers' capabilities. Although findings revealed that no significant differences in terms primary principals' demographics; male primary principals, and experienced between 6 and 10 years and positioned in schools with least students (SLS) category have slightly higher level of stress. In terms of Islamic coping strategies used by primary principals, saying dhua to Allah, performing dhikir and reciting the Yassen are selected coping approaches employed in handling their stress. From interviews, primary principals also revealed that they used Islamic religious approaches as part of meaningful activities not just to overcoming their stress but also as part of religious approaches in remembering Allah, thinking back their past mistakes as part of the Muhasabah process. Therefore, we believed that religious approaches should be taken into consideration in principals' training as it provides peaceful and treatment in managing principals' stress issue.

Young children's beliefs about self-disclosure of performance failure and success.

PubMed

Hicks, Catherine M; Liu, David; Heyman, Gail D

2015-03-01

Self-disclosure of performance information involves the balancing of instrumental, learning benefits (e.g., obtaining help) against social costs (e.g., diminished reputation). Little is known about young children's beliefs about performance self-disclosure. The present research investigates preschool- and early school-age children's expectations of self-disclosure in different contexts. In two experiments, 3- to 7-year-old children (total N = 252) heard vignettes about characters who succeeded or failed at solving a puzzle. Both experiments showed that children across all ages reasoned that people are more likely to self-disclose positive than negative performances, and Experiment 2 showed that children across all ages reasoned that people are more likely to self-disclose both positive and negative performances in a supportive than an unsupportive peer environment. Additionally, both experiments revealed changes with age - Younger children were less likely to expect people to withhold their performance information (of both failures and successes) than older children. These findings point to the preschool ages as a crucial beginning to children's developing recognition of people's reluctance to share performance information. © 2014 The British Psychological Society.

Itsy bitsy spider?: Valence and self-relevance predict size estimation.

PubMed

Leibovich, Tali; Cohen, Noga; Henik, Avishai

2016-12-01

The current study explored the role of valence and self-relevance in size estimation of neutral and aversive animals. In Experiment 1, participants who were highly fearful of spiders and participants with low fear of spiders rated the size and unpleasantness of spiders and other neutral animals (birds and butterflies). We found that although individuals with both high and low fear of spiders rated spiders as highly unpleasant, only the highly fearful participants rated spiders as larger than butterflies. Experiment 2 included additional pictures of wasps (not self-relevant, but unpleasant) and beetles. The results of this experiment replicated those of Experiment 1 and showed a similar bias in size estimation for beetles, but not for wasps. Mediation analysis revealed that in the high-fear group both relevance and valence influenced perceived size, whereas in the low-fear group only valence affected perceived size. These findings suggest that the effect of highly relevant stimuli on size perception is both direct and mediated by valence. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

New is not always costly: evidence from online processing of topic and contrast in Japanese

PubMed Central

Wang, Luming; Schumacher, Petra B.

2013-01-01

Two visual ERP experiments were conducted to investigate topic and contrast assigned by various cues such as discourse context, sentential position, and marker during referential processing in Japanese. Experiment 1 showed that there was no N400-difference for new vs. given noun phrases (NPs) when the new NP was expected (contrastively focused) based on its preceding context and sentential position. Experiment 2 further revealed that the N400 for new NPs can be modulated by the NP's contrastive meaning (exhaustivity) induced from the marker. Both experiments also showed that new NPs engendered an increased Late Positivity. The reduced N400 for new vs. given supports an expectation-based linking mechanism. In addition, costs that were consistently observed for new vs. given entities emerged in a subsequent process, in which the new NP's occurrence requires updating and correcting of the discourse representation built so far, which is indexed by an enhanced Late Positivity. We argue that the overall data pattern should be best explained within a multi-stream model of discourse processing. PMID:23825466

Gender differences in patterns of experienced sexual coercion and associated vulnerability factors among young people in the Netherlands.

PubMed

Kuyper, Lisette; de Wit, John; Smolenski, Derek; Adam, Philippe; Woertman, Liesbeth; van Berlo, Willy

2013-11-01

The development of effective policies and programs to prevent sexual coercion among young people requires thorough understanding of the diversity of coercive sexual experiences, patterns in such types of experiences, and similarities and differences between subgroups, especially by gender, in patterns of coercive sexual experiences and associations with potential vulnerability factors. The present online self-report study assessed a wide range of coercive sexual experiences and potential vulnerability factors among a sociodemographically diverse sample of 1,319 young people (16-25 years old) in The Netherlands. Findings confirm that sexual coercion comprises a diversity of experiences, with rates differing substantially across types of coercion. Latent class analysis revealed distinct patterns of coercive sexual experiences for young women and young men. Among young men, three patterns of experiences were found: no coercive sexual experiences, experience with verbal pressure, and experience with verbal pressure as well as coercion related to alcohol intoxication. Among young women, four patterns of coercive experiences were identified. In addition to the three patterns observed among young men, a fourth pattern encompassed experiences with verbal pressure as well as the use of force or violence. Higher numbers of sexual partners, lower levels of sexual refusal skills, and higher levels of token resistance were consistently associated with increased vulnerability. Findings illustrate the importance of communication skills and suggest that sexual communication training should be an integral part of sexuality education.

A Raman scattering and FT-IR spectroscopic study on the effect of the solar radiation in Antarctica on bovine cornea

NASA Astrophysics Data System (ADS)

Yamamoto, Tatsuyuki; Murakami, Naoki; Yoshikiyo, Keisuke; Takahashi, Tetsuya; Yamamoto, Naoyuki

2010-01-01

The Raman scattering and FT-IR spectra of the corneas, transported to the Syowa station in Antarctica and exposed to the solar radiation of the mid-summer for four weeks, were studied to reveal that type IV collagen involved in corneas were fragmented. The amide I and III Raman bands were observed at 1660 and 1245 cm -1, respectively, and the amide I and II infrared bands were observed at 1655 and 1545 cm -1, respectively, for original corneas before exposure. The background of Raman signals prominently increased and the ratio of amide II infrared band versus amide I decreased by the solar radiation in Antarctica. The control experiment using an artificial UV lamp was also performed in laboratory. The decline rate of the amide II/amide I was utilized for estimating the degree of fragmentation of collagen, to reveal that the addition of vitamin C suppressed the reaction while the addition of sugars promoted it. The effect of the solar radiation in Antarctica on the corneas was estimated as the same as the artificial UV lamp of four weeks (Raman) or one week (FT-IR) exposure.

Atomic-scale structural signature of dynamic heterogeneities in metallic liquids

NASA Astrophysics Data System (ADS)

Pasturel, Alain; Jakse, Noel

2017-08-01

With sufficiently high cooling rates, liquids will cross their equilibrium melting temperatures and can be maintained in a metastable undercooled state before solidifying. Studies of undercooled liquids reveal several intriguing dynamic phenomena and because explicit connections between liquid structure and liquids dynamics are difficult to identify, it remains a major challenge to capture the underlying structural link to these phenomena. Ab initio molecular dynamics (AIMD) simulations are yet especially powerful in providing atomic-scale details otherwise not accessible in experiments. Through the AIMD-based study of Cr additions in Al-based liquids, we evidence for the first time a close relationship between the decoupling of component diffusion and the emergence of dynamic heterogeneities in the undercooling regime. In addition, we demonstrate that the origin of both phenomena is related to a structural heterogeneity caused by a strong interplay between chemical short-range order (CSRO) and local fivefold topology (ISRO) at the short-range scale in the liquid phase that develops into an icosahedral-based medium-range order (IMRO) upon undercooling. Finally, our findings reveal that this structural signature is also captured in the temperature dependence of partial pair-distribution functions which opens up the route to more elaborated experimental studies.

Unveiling Singlet Fission Mediating States in TIPS-pentacene and its Aza Derivatives.

PubMed

Herz, Julia; Buckup, Tiago; Paulus, Fabian; Engelhart, Jens U; Bunz, Uwe H F; Motzkus, Marcus

2015-06-25

Femtosecond pump-depletion-probe experiments were carried out in order to shed light on the ultrafast excited-state dynamics of triisopropylsilylethynyl (TIPS)-pentacene and two nitrogen-containing derivatives, namely, diaza-TIPS-pentacene and tetraaza-TIPS-pentacene. Measurements performed in the visible and near-infrared spectral range in combination with rate model simulations reveal that singlet fission proceeds via the extremely short-lived intermediate (1)TT state, which absorbs in the near-infrared spectral region only. The T1 → T3 transition probed in the visible region shows a rise time that comprises two components according to a consecutive reaction (S1 → (1)TT → T1). The incorporation of nitrogen atoms into the acene structure leads to shorter dynamics, but the overall triplet formation follows the same kinetic model. This is of particular importance, since experiments on tetraaza-TIPS-pentacene allow for investigation of the triplet state in the visible range without an overlapping singlet contribution. In addition, the pump-depletion-probe experiments show that the triplet absorption in the visible (T1 → T3) and near-infrared (T1 → T2) regions occurs from the same initial state, which was questioned in previous studies. Furthermore, an additional ultrafast transfer between the excited triplet states (T3 → T2) is identified, which is also in agreement with the rate model simulation. By applying depletion pulses, which are resonant with higher vibrational levels, we gain insight into internal vibrational energy redistribution processes within the triplet manifold. This additional information is of great relevance regarding the study of loss channels within these materials.

Monthly streamflow forecasting at varying spatial scales in the Rhine basin

NASA Astrophysics Data System (ADS)

Schick, Simon; Rössler, Ole; Weingartner, Rolf

2018-02-01

Model output statistics (MOS) methods can be used to empirically relate an environmental variable of interest to predictions from earth system models (ESMs). This variable often belongs to a spatial scale not resolved by the ESM. Here, using the linear model fitted by least squares, we regress monthly mean streamflow of the Rhine River at Lobith and Basel against seasonal predictions of precipitation, surface air temperature, and runoff from the European Centre for Medium-Range Weather Forecasts. To address potential effects of a scale mismatch between the ESM's horizontal grid resolution and the hydrological application, the MOS method is further tested with an experiment conducted at the subcatchment scale. This experiment applies the MOS method to 133 additional gauging stations located within the Rhine basin and combines the forecasts from the subcatchments to predict streamflow at Lobith and Basel. In doing so, the MOS method is tested for catchments areas covering 4 orders of magnitude. Using data from the period 1981-2011, the results show that skill, with respect to climatology, is restricted on average to the first month ahead. This result holds for both the predictor combination that mimics the initial conditions and the predictor combinations that additionally include the dynamical seasonal predictions. The latter, however, reduce the mean absolute error of the former in the range of 5 to 12 %, which is consistently reproduced at the subcatchment scale. An additional experiment conducted for 5-day mean streamflow indicates that the dynamical predictions help to reduce uncertainties up to about 20 days ahead, but it also reveals some shortcomings of the present MOS method.

Nanohybrid conjugated polyelectrolytes: highly photostable and ultrabright nanoparticles

NASA Astrophysics Data System (ADS)

Darwish, Ghinwa H.; Karam, Pierre

2015-09-01

We present a general and straightforward one-step approach to enhance the photophysical properties of conjugated polyelectrolytes. Upon complexation with an amphiphilic polymer (polyvinylpyrrolidone), an anionic conjugated polyelectrolyte (poly[5-methoxy-2-(3-sulfopropoxy)-1,4-phenylenevinylene]) was prepared into small nanoparticles with exceptional photostability and brightness. The polymer fluorescence intensity was enhanced by 23 -fold and could be easily tuned by changing the order of addition. Single molecule experiments revealed a complete suppression of blinking. In addition, after only losing 18% of the original intensity, a remarkable amount of photons were emitted per particle (~109, on average). This number is many folds greater than popular organic fluorescent dyes. We believe that an intimate contact between the two polymers is shielding the conjugated polyelectrolyte from the destructive photooxidation. The prepared nanohybrid particles will prove instrumental in single particle based fluorescent assays and can serve as a probe for the current state-of-the-art bioimaging fluorescence techniques.We present a general and straightforward one-step approach to enhance the photophysical properties of conjugated polyelectrolytes. Upon complexation with an amphiphilic polymer (polyvinylpyrrolidone), an anionic conjugated polyelectrolyte (poly[5-methoxy-2-(3-sulfopropoxy)-1,4-phenylenevinylene]) was prepared into small nanoparticles with exceptional photostability and brightness. The polymer fluorescence intensity was enhanced by 23 -fold and could be easily tuned by changing the order of addition. Single molecule experiments revealed a complete suppression of blinking. In addition, after only losing 18% of the original intensity, a remarkable amount of photons were emitted per particle (~109, on average). This number is many folds greater than popular organic fluorescent dyes. We believe that an intimate contact between the two polymers is shielding the conjugated polyelectrolyte from the destructive photooxidation. The prepared nanohybrid particles will prove instrumental in single particle based fluorescent assays and can serve as a probe for the current state-of-the-art bioimaging fluorescence techniques. Electronic supplementary information (ESI) available: Dynamic light scattering, photostability of different nanohybrids, and emission and absorption spectra. See DOI: 10.1039/c5nr03299g

Methane oxidation in anoxic lake waters

NASA Astrophysics Data System (ADS)

Su, Guangyi; Zopfi, Jakob; Niemann, Helge; Lehmann, Moritz

2017-04-01

Freshwater habitats such as lakes are important sources of methante (CH4), however, most studies in lacustrine environments so far provided evidence for aerobic methane oxidation only, and little is known about the importance of anaerobic oxidation of CH4 (AOM) in anoxic lake waters. In marine environments, sulfate reduction coupled to AOM by archaea has been recognized as important sinks of CH4. More recently, the discorvery of anaerobic methane oxidizing denitrifying bacteria represents a novel and possible alternative AOM pathway, involving reactive nitrogen species (e.g., nitrate and nitrite) as electron acceptors in the absence of oxygen. We investigate anaerobic methane oxidation in the water column of two hydrochemically contrasting sites in Lake Lugano, Switzerland. The South Basin displays seasonal stratification, the development of a benthic nepheloid layer and anoxia during summer and fall. The North Basin is permanently stratified with anoxic conditions below 115m water depth. Both Basins accumulate seasonally (South Basin) or permanently (North Basin) large amounts of CH4 in the water column below the chemocline, providing ideal conditions for methanotrophic microorganisms. Previous work revealed a high potential for aerobic methane oxidation within the anoxic water column, but no evidence for true AOM. Here, we show depth distribution data of dissolved CH4, methane oxidation rates and nutrients at both sites. In addition, we performed high resolution phylogenetic analyses of microbial community structures and conducted radio-label incubation experiments with concentrated biomass from anoxic waters and potential alternative electron acceptor additions (nitrate, nitrite and sulfate). First results from the unamended experiments revealed maximum activity of methane oxidation below the redoxcline in both basins. While the incubation experiments neither provided clear evidence for NOx- nor sulfate-dependent AOM, the phylogenetic analysis revealed the presence of members of the Methylomirabiliaceae family (NC10 phylum), known to perform AOM with nitrite as terminal electron acceptor. Interestingly, albeit the similarly favorable conditions in both basins, the South Basin showed nearly two-fold higher CH4 oxidation rates, but the Methylomirabiliaceae abundance appeared to be much higher in the meromictic North Basin. Ongoing work will attempt to verify whether the apparent difference in the abundance of Methylomirabiliaceae is a permanent feature. We will further seek to determine the relative contribution of bacterial nitrite-dependent AOM to total methane oxidation, as well as the environmental controls that may explain the differential importance of Methylomirabiliaceae in the two connected lake basins.

Effect of salinity and inorganic nitrogen concentrations on nitrification and denitrification rates in intertidal sediments and rocky biofilms of the Douro River estuary, Portugal.

PubMed

Magalhães, Catarina M; Joye, Samantha B; Moreira, Rosa M; Wiebe, William J; Bordalo, Adriano A

2005-05-01

The regulatory effects of salinity and inorganic nitrogen compounds on nitrification and denitrification were studied in intertidal sandy sediments and rocky biofilms in the Douro River estuary, Portugal, over a 12-month period. Nitrification and denitrification rates were measured in slurries of field samples and enrichment experiments using the difluoromethane and the acetylene inhibition techniques, respectively. Salinity did not regulate denitrification in either environment, suggesting that halotolerant bacteria dominated the denitrifier communities. However, nitrification rates were stimulated when salinity increased from 0 to 15 practical salinity units. NO3- addition experiments revealed that NO3- availability stimulates denitrification rates in sandy sediments, but not in rocky biofilms; however, in rocky biofilms a positive and linear relationship was observed between denitrification rates and water column NO3- concentrations (r=0.92) during the monthly surveys. The N2O:N2 ratios increased rapidly when NO3- increased from 63 to 363 microM; however, results from monthly surveys showed that environmental parameters other than NO3- availability may be important in controlling the variation in N2O production via denitrification. Ammonium additions to sandy sediments stimulated nitrification rates by 35% for the 20 microM NH4+ addition, but NH4+ appeared to inhibit nitrification at high concentration addition (200 microM NH4+). In contrast, rocky biofilm nitrification was stimulated by 65% when 200 microM NH4+ was added.

Gender Differences in Emotional Response: Inconsistency between Experience and Expressivity.

PubMed

Deng, Yaling; Chang, Lei; Yang, Meng; Huo, Meng; Zhou, Renlai

2016-01-01

The present study investigated gender differences in both emotional experience and expressivity. Heart rate (HR) was recorded as an indicator of emotional experience while the participants watched 16 video clips that induced eight types of emotion (sadness, anger, horror, disgust, neutrality, amusement, surprise, and pleasure). We also asked the participants to report valence, arousal, and motivation as indicators of emotional expressivity. Overall, the results revealed gender differences in emotional experience and emotional expressivity. When watching videos that induced anger, amusement, and pleasure, men showed larger decreases in HR, whereas women reported higher levels of arousal. There was no gender difference in HR when the participants watched videos that induced horror and disgust, but women reported lower valence, higher arousal, and stronger avoidance motivation than did men. Finally, no gender difference was observed in sadness or surprise, although there was one exception-women reported higher arousal when watching videos that induced sadness. The findings suggest that, when watching videos that induce an emotional response, men often have more intense emotional experiences, whereas women have higher emotional expressivity, particularly for negative emotions. In addition, gender differences depend on the specific emotion type but not the valence.

Links between Family Gender Socialization Experiences in Childhood and Gendered Occupational Attainment in Young Adulthood.

PubMed

Lawson, Katie M; Crouter, Ann C; McHale, Susan M

2015-10-01

Gendered occupational segregation remains prevalent across the world. Although research has examined factors contributing to the low number of women in male-typed occupations - namely science, technology, engineering, and math - little longitudinal research has examined the role of childhood experiences in both young women's and men's later gendered occupational attainment. This study addressed this gap in the literature by examining family gender socialization experiences in middle childhood - namely parents' attitudes and work and family life - as contributors to the gender typicality of occupational attainment in young adulthood. Using data collected from mothers, fathers, and children over approximately 15 years, the results revealed that the associations between childhood socialization experiences (∼10 years old) and occupational attainment (∼26 years old) depended on the sex of the child. For sons but not daughters, mothers' more traditional attitudes towards women's roles predicted attaining more gender-typed occupations. In addition, spending more time with fathers in childhood predicted daughters attaining less and sons acquiring more gender-typed occupations in young adulthood. Overall, evidence supports the idea that childhood socialization experiences help to shape individuals' career attainment and thus contribute to gender segregation in the labor market.

Gender Differences in Emotional Response: Inconsistency between Experience and Expressivity

PubMed Central

Deng, Yaling; Chang, Lei; Yang, Meng; Huo, Meng

2016-01-01

The present study investigated gender differences in both emotional experience and expressivity. Heart rate (HR) was recorded as an indicator of emotional experience while the participants watched 16 video clips that induced eight types of emotion (sadness, anger, horror, disgust, neutrality, amusement, surprise, and pleasure). We also asked the participants to report valence, arousal, and motivation as indicators of emotional expressivity. Overall, the results revealed gender differences in emotional experience and emotional expressivity. When watching videos that induced anger, amusement, and pleasure, men showed larger decreases in HR, whereas women reported higher levels of arousal. There was no gender difference in HR when the participants watched videos that induced horror and disgust, but women reported lower valence, higher arousal, and stronger avoidance motivation than did men. Finally, no gender difference was observed in sadness or surprise, although there was one exception—women reported higher arousal when watching videos that induced sadness. The findings suggest that, when watching videos that induce an emotional response, men often have more intense emotional experiences, whereas women have higher emotional expressivity, particularly for negative emotions. In addition, gender differences depend on the specific emotion type but not the valence. PMID:27362361

Phonological bases for L2 morphological learning.

PubMed

Hu, Chieh-Fang

2010-08-01

Two experiments examined the hypothesis that L1 phonological awareness plays a role in children's ability to extract morphological patterns of English as L2 from the auditory input. In Experiment 1, 84 Chinese-speaking third graders were tested on whether they extracted the alternation pattern between the base and the derived form (e.g., inflate - inflation) from multiple exposures. Experiment 2 further assessed children's ability to use morphological cues for syntactic categorization through exposures to novel morphologically varying forms (e.g., lutate vs. lutant) presented in the corresponding sentential positions (noun vs. verb). The third-grade EFL learners revealed emergent sensitivity to the morphological cues in the input but failed in fully processing intraword variations. The learners with poorer L1 PA were likely to encounter difficulties in identifying morphological alternation rules and in discovering the syntactic properties of L2 morphology. In addition to L1 PA, L2 vocabulary knowledge also contributed significantly to L2 morphological learning.

Comparisons of mental clocks.

PubMed

Paivio, A

1978-02-01

Subjects in three experiments were presented with pairs of clock times and were required to choose the one in which the hour and minute hand formed the smaller angle. In Experiments 1 and 2, the times were presented digitally, necessitating a transformation into symbolic representations from which the angular size difference could be inferred. The results revealed orderly symbolic distance effects so that comparison reaction time increased as the angular size difference decreased. Moreover, subjects generally reported using imagery to make the judgment, and subjects scoring high on test of imagery ability were faster than those scoring low on such tests. Experiment 3 added a direct perceptual condition in which subjects compared angles between pairs of hands on two drawn (analog) clocks, as well as a mixed condition involving one digital and one analog clock time. The results showed comparable distance effects for all conditions. In addition, reaction time increased from the perceptual, to the mixed, to the pure-digital condition. These results are consistent with predictions from an image-based dual-coding theory.

Predictors of online and offline sexual activities and behaviors among adolescents.

PubMed

Sevčíková, Anna; Vazsonyi, Alexander T; Sirůček, Jan; Konečný, Stěpán

2013-08-01

Despite the fact that many adolescents spend much time on the Internet, it is unknown who engages in sexually related online activities (SROA) and how these affect adolescent sexual development. The present longitudinal study on 323 adolescents (51.1% girls) aimed to explore how peer attachment processes predicted both SROA and offline sexual behaviors at the age of 17, while also considering puberty and prior offline sexual experiences in order to elucidate potential similarities or differences. Findings based on hierarchical, binary logistic regression analyses revealed that SROA were predicted by alienation attachment to peers (OR=3.36, p<0.05), puberty (OR=1.03, p<0.05), and prior SROA (OR=0.56, p<0.001), while only previous offline sexual experiences at the age of 15 increased the likelihood of offline sexual behaviors at the age of 17 (OR=6.04, p<0.001). Study findings indicate that the Internet provides an additional context for acquiring sexual experiences during adolescence.

Death Attitudes Among Middle-Aged Koreans: Role of End-of-Life Care Planning and Death Experiences

PubMed Central

Hong, Michin; Hong, Seunghye; Adamek, Margaret E.; Kim, Mee Hye

2017-01-01

The purpose of this study was to examine factors affecting death attitudes among middle-aged Koreans. In addition, the study explored the interaction effect between knowledge about end-of-life care planning and the experience of death of family or friends on death attitudes. The sample was obtained from a national survey with middle-aged adults in South Korea (n = 2,026). Multivariate regression analysis revealed significant main effects and an interaction effect between knowledge about end-of-life care planning and the experience of death on death attitudes. Greater knowledge of end-of-life care planning was associated with more positive attitudes toward death; however, the effect was stronger for those who had not experienced the death of family or friends. Being older and having greater life satisfaction were also associated with more positive attitudes toward death. This study suggests that end-of-life education can help middle-aged adults embrace the final stage of life and prepare for their own death. PMID:28105867

Legality, Racialization, and Immigrants’ Experience of Ethnoracial Harassment in Russia

PubMed Central

Agadjanian, Victor; Menjívar, Cecilia; Zotova, Natalya

2017-01-01

Using data from a structured survey and in-depth interviews in three Russian cities, our study engages the scholarship on immigration legal regimes and racialization practices to examine the experiences of ethnoracially motivated harassment among working migrant women from Kyrgyzstan, Tajikistan, and Uzbekistan in Russia. The results of statistical analyses show that regularized legal status is associated with a significantly lower likelihood of experiencing harassment at the hands of law enforcement agents and other actors alike. Regardless of legal status, however, the analyses reveal significant variations across the three migrant groups, with members of the group that is seen as racially most distinct from the host population having the highest odds of reporting harassment. The analysis of in-depth interviews confirms and expands on these patterns, providing additional insights into the complex expressions and interplay of legality and race in migrants’ everyday experiences. The study findings are situated within the cross-national literature on migrants’ legal and ethnoracial exclusion in receiving contexts. PMID:29109593

Evidence for two attentional components in visual working memory.

PubMed

Allen, Richard J; Baddeley, Alan D; Hitch, Graham J

2014-11-01

How does executive attentional control contribute to memory for sequences of visual objects, and what does this reveal about storage and processing in working memory? Three experiments examined the impact of a concurrent executive load (backward counting) on memory for sequences of individually presented visual objects. Experiments 1 and 2 found disruptive concurrent load effects of equivalent magnitude on memory for shapes, colors, and colored shape conjunctions (as measured by single-probe recognition). These effects were present only for Items 1 and 2 in a 3-item sequence; the final item was always impervious to this disruption. This pattern of findings was precisely replicated in Experiment 3 when using a cued verbal recall measure of shape-color binding, with error analysis providing additional insights concerning attention-related loss of early-sequence items. These findings indicate an important role for executive processes in maintaining representations of earlier encountered stimuli in an active form alongside privileged storage of the most recent stimulus. PsycINFO Database Record (c) 2014 APA, all rights reserved.

SUMO Nitrogen Labeling Experiment and Soil Biogeochemistry

DOE Data Explorer

Grossiord, Charlotte [Swiss Federal Research Institute WSL; Gessler, Arthur [Swiss Federal Research Institute WSL; Reed, Sasha [USGS; Borrego, Isaac [USGS; Collins, Adam [Los Alamos National Laboratory; Dickman, Turin L. [Los Alamos National Laboratory; Ryan, Max [Los Alamos National Laboratory; Schönbeck, Leonie [Swiss Federal Research Institute WSL; Sevanto, Sanna [Los Alamos National Laboratory; Villagrosa, Alberto [University of Alicante; McDowell, Nate [Pacific Northwest National Laboratory (PNNL)

2018-01-01

The Los Alamos Survival–Mortality experiment (SUMO) is located on Frijoles Mesa near Los Alamos, New Mexico, USA, at an elevation of 2150 m. This was a tree manipulation study that investigated the relative impacts of drought and warming on plant function and reveals how trees adapt to drought and heat in semi-arid regions. The study factored the role of tree hydraulic acclimation to both precipitation and temperature and separated their effects.The experiment is located in a pinon-juniper woodland near the ponderosa pine (Pinus ponderosa) forest ecotone. In a semi-arid woodland, adult trees (piñon and juniper) were exposed to chronic warming (+4 °C) and precipitation reduction (-45 %). After five years of continuous treatment exposure, soil and plant nitrogen isotopic composition were measured to assess plant nitrogen allocation. See SUMO Target Tree Information data package (doi:10.15485/1440544) for additional information. Data released by Los Alamos National Lab for public use under LA-UR-18-23656.

You don't have to believe everything you read: background knowledge permits fast and efficient validation of information.

PubMed

Richter, Tobias; Schroeder, Sascha; Wöhrmann, Britta

2009-03-01

In social cognition, knowledge-based validation of information is usually regarded as relying on strategic and resource-demanding processes. Research on language comprehension, in contrast, suggests that validation processes are involved in the construction of a referential representation of the communicated information. This view implies that individuals can use their knowledge to validate incoming information in a routine and efficient manner. Consistent with this idea, Experiments 1 and 2 demonstrated that individuals are able to reject false assertions efficiently when they have validity-relevant beliefs. Validation processes were carried out routinely even when individuals were put under additional cognitive load during comprehension. Experiment 3 demonstrated that the rejection of false information occurs automatically and interferes with affirmative responses in a nonsemantic task (epistemic Stroop effect). Experiment 4 also revealed complementary interference effects of true information with negative responses in a nonsemantic task. These results suggest the existence of fast and efficient validation processes that protect mental representations from being contaminated by false and inaccurate information.

Feature-specific attention allocation modulates the generalization of recently acquired likes and dislikes.

PubMed

Spruyt, Adriaan; Klauer, Karl Christoph; Gast, Anne; De Schryver, Maarten; De Houwer, Jan

2014-01-01

We examined whether the generalization of recently acquired likes and dislikes depends on feature-specific attention allocation. Likes and dislikes were established by means of an evaluative-conditioning procedure in which participants were presented with several exemplars of two subordinate categories (e.g., young men vs. old women). Whereas exemplars of one category were consistently paired with negative stimuli, exemplars of the second category were consistently paired with positive stimuli. In addition, we manipulated feature-specific attention allocation for specific stimulus dimensions (e.g., gender vs. age), either during (Experiments 1 and 2) or before the acquisition phase of the experiment (Experiment 3). Both direct and indirect attitude measures revealed a clear impact of this manipulation on attitude generalization. More specifically, only generalization stimuli that were similar to the CSs in terms of the stimulus dimension that was selectively attended to were evaluated in a manner that was congruent with the acquired liking of those CSs.

The speed of metacognition: taking time to get to know one's structural knowledge.

PubMed

Mealor, Andy D; Dienes, Zoltan

2013-03-01

The time course of different metacognitive experiences of knowledge was investigated using artificial grammar learning. Experiment 1 revealed that when participants are aware of the basis of their judgments (conscious structural knowledge) decisions are made most rapidly, followed by decisions made with conscious judgment but without conscious knowledge of underlying structure (unconscious structural knowledge), and guess responses (unconscious judgment knowledge) were made most slowly, even when controlling for differences in confidence and accuracy. In experiment 2, short response deadlines decreased the accuracy of unconscious but not conscious structural knowledge. Conversely, the deadline decreased the proportion of conscious structural knowledge in favour of guessing. Unconscious structural knowledge can be applied rapidly but becomes more reliable with additional metacognitive processing time whereas conscious structural knowledge is an all-or-nothing response that cannot always be applied rapidly. These dissociations corroborate quite separate theories of recognition (dual-process) and metacognition (higher order thought and cross-order integration). Copyright © 2012 Elsevier Inc. All rights reserved.

Death Attitudes Among Middle-Aged Koreans: Role of End-of-Life Care Planning and Death Experiences.

PubMed

Hong, Michin; Hong, Seunghye; Adamek, Margaret E; Kim, Mee Hye

2018-01-01

The purpose of this study was to examine factors affecting death attitudes among middle-aged Koreans. In addition, the study explored the interaction effect between knowledge about end-of-life care planning and the experience of death of family or friends on death attitudes. The sample was obtained from a national survey with middle-aged adults in South Korea ( n = 2,026). Multivariate regression analysis revealed significant main effects and an interaction effect between knowledge about end-of-life care planning and the experience of death on death attitudes. Greater knowledge of end-of-life care planning was associated with more positive attitudes toward death; however, the effect was stronger for those who had not experienced the death of family or friends. Being older and having greater life satisfaction were also associated with more positive attitudes toward death. This study suggests that end-of-life education can help middle-aged adults embrace the final stage of life and prepare for their own death.

Legality, Racialization, and Immigrants' Experience of Ethnoracial Harassment in Russia.

PubMed

Agadjanian, Victor; Menjívar, Cecilia; Zotova, Natalya

2017-11-01

Using data from a structured survey and in-depth interviews in three Russian cities, our study engages the scholarship on immigration legal regimes and racialization practices to examine the experiences of ethnoracially motivated harassment among working migrant women from Kyrgyzstan, Tajikistan, and Uzbekistan in Russia. The results of statistical analyses show that regularized legal status is associated with a significantly lower likelihood of experiencing harassment at the hands of law enforcement agents and other actors alike. Regardless of legal status, however, the analyses reveal significant variations across the three migrant groups, with members of the group that is seen as racially most distinct from the host population having the highest odds of reporting harassment. The analysis of in-depth interviews confirms and expands on these patterns, providing additional insights into the complex expressions and interplay of legality and race in migrants' everyday experiences. The study findings are situated within the cross-national literature on migrants' legal and ethnoracial exclusion in receiving contexts.

Comparing slow and fast rupture in laboratory experiments

NASA Astrophysics Data System (ADS)

Aben, F. M.; Brantut, N.; David, E.; Mitchell, T. M.

2017-12-01

During the brittle failure of rock, elastically stored energy is converted into a localized fracture plane and surrounding fracture damage, seismic radiation, and thermal energy. However, the partitioning of energy might vary with the rate of elastic energy release during failure. Here, we present the results of controlled (slow) and dynamic (fast) rupture experiments on dry Lanhélin granite and Westerly granite samples, performed under triaxial stress conditions at confining pressures of 50 and 100 MPa. During the tests, we measured sample shortening, axial load and local strains (with 2 pairs of strain gauges glued directly onto the sample). In addition, acoustic emissions (AEs) and changes in seismic velocities were monitored. The AE rate was used as an indicator to manually control the axial load on the sample to stabilize rupture in the quasi-static failure experiments. For the dynamic rupture experiments a constant strain rate of 10-5 s-1 was applied until sample failure. A third experiment, labeled semi-controlled rupture, involved controlled rupture up to a point where the rupture became unstable and the remaining elastic energy was released dynamically. All experiments were concluded after a macroscopic fracture had developed across the whole sample and frictional sliding commenced. Post-mortem samples were epoxied, cut and polished to reveal the macroscopic fracture and the surrounding damage zone. The samples failed with average rupture velocities varying from 5x10-6 m/s up to >> 0.1 m/s. The analyses of AE locations on the slow ruptures reveal that within Westerly granite samples - with a smaller grain size - fracture planes are disbanded in favor of other planes when a geometrical irregularity is encountered. For the coarser grained Lanhélin granite a single fracture plane is always formed, although irregularities are recognized as well. The semi-controlled experiments show that for both rock types the rupture can become unstable in response to these irregularities. In Westerly granite, slow rupture experiments tend to produce complex fracture patterns while during the dynamic rupture experiments secondary rupture planes are not formed. These findings show that grain or flaw size, flaw distribution, and rupture speed strongly influence fracture localization and propagation.

Testing different versions of the Affective Neuroscience Personality Scales in a clinical sample.

PubMed

Pedersen, Geir; Geir, Pedersen; Selsbakk, Johansen Merete; Theresa, Wilberg; Sigmund, Karterud

2014-01-01

As a tool to investigate the experiences of six primary emotions, Davis, Panksepp, and Normansell developed the Affective Neuroscience Personality Scales (ANPS). However, the psychometric properties of the ANPS have been questioned, and in particular the factor structure. This study replicates earlier psychometric studies on ANPS in a sample of (546) personality disordered patients, and also includes ANPS-S, a recent short version of ANPS by Pingault and colleagues, and a truncated version of BANPS by Barrett and colleagues. The study of the full ANPS revealed acceptable internal consistencies of the primary emotion subscales, ranging from 0.74-0.87. However, factor analyses revealed poor to mediocre fit for a six factor solution. Correlational analyses, in addition, revealed too high correlations between PLAY and SEEK, and between SADNESS and FEAR. The two short versions displayed better psychometric properties. The range of internal consistency was 0.61-0.80 for the BANPS scales and 0.65-84 for the ANPS-S. Backward Cronbach Alpha Curves indicated potentials for improvement on all three versions of the questionnaire. Items retained in the short versions did not systematically cover the full theoretical content of the long scales, in particular for CARE and SADNESS in the BANPS. The major problems seem to reside in the operationalization of the CARE and SADNESS subscales of ANPS. Further work needs to be done in order to realize a psychometrically sound instrument for the assessment of primary emotional experiences.

Retelling the educational pathways of Black women physicists: Stories of experiencing and overcoming obstacles in life

NASA Astrophysics Data System (ADS)

Mensah, Felicia

This is an empirical study on the underrepresentation of people of color in scientific careers. Grounded in critical race theory, the paper examines the lived experiences of six Black women physicists and addresses obstacles faced in their career paths and strategies used to overcome these obstacles. Data for this study were collected through semi-structured interviews and coded for emergent themes. The findings reveal that college recruitment and funding were fundamental for these women to choose physics over other STEM fields. In addition, Black women experience unique challenges of socialization in STEM, particularly by exclusion of study groups. We suggest physics departments provide a more inclusive environment to support Black women in science. CAPES, the Fulbright Program, Comissão Fulbright Brasil, and the Office of Diversity at Teachers College, Columbia University.

SUMO Chamber Conditions

DOE Data Explorer

Sevanto, Sanna [Los Alamos National Laboratory; Powers, Heath [Los Alamos National Laboratory; Dickman, Turin L. [Los Alamos National Laboratory; Collins, Adam [Los Alamos National Laboratory; Grossiord, Charlotte [Swiss Federal Institute for Forest Snow and Landscape Research; Adams, Henry [Oklahoma State University; Borrego, Isaac [USGS Southwest Biological Science Center; McDowell, Nate [Pacific Northwest National Laboratory (PNNL); Stockton, Elizabeth [University of New Mexico; Ryan, Max [Los Alamos National Laboratory; Slentz, Matthew [Mohle Adams; Briggs, Sam [Fossil Creek Nursery; McBranch, Natalie [Los Alamos National Laboratory; Morgan, Bryn [Los Alamos National Laboratory

2018-01-01

The Los Alamos Survival–Mortality experiment (SUMO) is located on Frijoles Mesa near Los Alamos, New Mexico, USA, at an elevation of 2150 m. This was a tree manipulation study that investigated the relative impacts of drought and warming on plant function and reveals how trees adapt to drought and heat in semi-arid regions. The study factored the role of tree hydraulic acclimation to both precipitation and temperature and separated their effects.The experiment is located in a pinon-juniper woodland near the ponderosa pine (Pinus ponderosa) forest ecotone. Chamber conditions (temperature, relative humidity, vapor pressure deficit) for SUMO Open Top Chambers (OTCs) used to control air temperatures surrounding heated and control chamber trees. See SUMO Target Tree Information data package (doi:10.15485/1440544) for additional information. Data released by Los Alamos National Lab for public use under LA-UR-18-23656.

Identification and ultra-high-performance liquid chromatography coupled with high-resolution mass spectrometry characterization of biosurfactants, including a new surfactin, isolated from oil-contaminated environments.

PubMed

Moro, Glaci V; Almeida, Rafaela T R; Napp, Amanda P; Porto, Carla; Pilau, Eduardo J; Lüdtke, Diogo S; Moro, Angélica V; Vainstein, Marilene H

2018-05-14

Biosurfactant-producing bacteria were isolated from samples collected in areas contaminated with crude oil. The isolates were screened for biosurfactant production using qualitative drop-collapse test, oil-spreading and emulsification assays, and measurement of their tensoactive properties. Five isolates tested positive for in the screening experiments and displayed decrease in the surface tension below 30 mN m -1 . The biosurfactants produced by these isolates were further investigated and their molecular identification revealed that they are bacteria related to the Bacillus genus. Additionally, the biosurfactants produced were chemically characterized via UHPLC-HRMS experiments, indicating the production of surfactin homologues, including a new class of these molecules. © 2018 The Authors. Microbial Biotechnology published by John Wiley & Sons Ltd and Society for Applied Microbiology.

PERCEIVED RACIAL DISCRIMINATION AMONG HOME HEALTH AIDES: EVIDENCE FROM A NATIONAL SURVEY.

PubMed

Lee, Doohee; Muslin, Ivan; McInerney, Marjorie

2016-01-01

Home health aides are one of our essential human resources in the U.S. long-term care industry but understanding whether home health aides experience racial discrimination in the workplace and, if so, which personal/organizational factors are associated at the national level has been unnoticed. Using a nationally representative sample (n=3377), we attempt to investigate the association between racial discrimination and personal and organizational factors. The study found the 13.5% prevalence rate of racial discrimination. The study findings from multiple regression analysis reveal that black home care aides are more likely than white aides to experience racial discrimination in the workplace, suggesting that racial disparity may be an additional barrier to our home health care industry. National chain affiliation and low income were also found to be associated with perceived racial discrimination.

TEM Analysis of Diffusion-Bonded Silicon Carbide Ceramics Joined Using Metallic Interlayers

NASA Technical Reports Server (NTRS)

Ozaki, T.; Hasegawa, Y.; Tsuda, H.; Mori, S.; Halbig, M. C.; Asthana, R.; Singh, M.

2017-01-01

SiC fiber-bonded ceramics (SA-Tyrannohex: SA-THX) diffusion-bonded with TiCu metallic interlayers were investigated. Thin samples of the ceramics were prepared with a focused ion beam (FIB) and the interfacial microstructure of the prepared samples was studied by transmission electron microscopy (TEM) and scanning TEM (STEM). In addition to conventional microstructure observation, for detailed analysis of reaction compounds in diffusion-bonded area, we performed STEM-EDS measurements and selected area electron diffraction (SAD) experiments. The TEM and STEM experiments revealed the diffusion-bonded area was composed of only one reaction layer, which was characterized by TiC precipitates in Cu-Si compound matrix. This reaction layer was in good contact with the SA-THX substrates, and it is concluded that the joint structure led to the excellent bonding strength.

Enhancing the blue shift of SHG signal in GaSe:B/Ce crystal

NASA Astrophysics Data System (ADS)

Karatay, Ahmet; Yuksek, Mustafa; Ertap, Hüseyin; Elmali, Ayhan; Karabulut, Mevlut

2018-02-01

The influence of Ce3+ on the wavelength of second harmonic generation (SHG) signal in boron doped GaSe crystals have been investigated. We found that by substitution of Ce3+ with B3+, SHG signal shifted to lower wavelength. In addition, the nonlinear absorption (NA) properties and ultrafast dynamics of pure, 1 at.% B3+ and 0.5 at.% B3++ 0.5 at.% Ce3+ doped GaSe crystals have been studied by open aperture Z-scan and ultrafast pump probe spectroscopy techniques. From the open aperture Z-scan experiments we observed that all of the crystals showed nonlinear absorption (NA). However, pump-probe experiments revealed that when GaSe crystal is doped, the NA signal turns into a bleaching signal with different lifetimes depending on the type and concentration of the dopant atoms.

Serial migration and its implications for the parent-child relationship: a retrospective analysis of the experiences of the children of Caribbean immigrants.

PubMed

Smith, Andrea; Lalonde, Richard N; Johnson, Simone

2004-05-01

This study addressed the potential impact of serial migration for parent-children relationships and for children's psychological well-being. The experience of being separated from their parents during childhood and reunited with them at a later time was retrospectively examined for 48 individuals. A series of measures (e.g., self-esteem, parental identification) associated with appraisals at critical time periods during serial migration (separation, reunion, current) revealed that serial migration can potentially disrupt parent-child bonding and unfavorably affect children's self-esteem and behavior. Time did not appear to be wholly effective in repairing rifts in the parent-child relationship. Risk factors for less successful reunions included lengthy separations and the addition of new members to the family unit in the child's absence. (c) 2004 APA

Metal-Polycyclic Aromatic Hydrocarbon Mixture Toxicity in Hyalella azteca. 1. Response Surfaces and Isoboles To Measure Non-additive Mixture Toxicity and Ecological Risk.

PubMed

Gauthier, Patrick T; Norwood, Warren P; Prepas, Ellie E; Pyle, Greg G

2015-10-06

Mixtures of metals and polycyclic aromatic hydrocarbons (PAHs) occur ubiquitously in aquatic environments, yet relatively little is known regarding their potential to produce non-additive toxicity (i.e., antagonism or potentiation). A review of the lethality of metal-PAH mixtures in aquatic biota revealed that more-than-additive lethality is as common as strictly additive effects. Approaches to ecological risk assessment do not consider non-additive toxicity of metal-PAH mixtures. Forty-eight-hour water-only binary mixture toxicity experiments were conducted to determine the additive toxic nature of mixtures of Cu, Cd, V, or Ni with phenanthrene (PHE) or phenanthrenequinone (PHQ) using the aquatic amphipod Hyalella azteca. In cases where more-than-additive toxicity was observed, we calculated the possible mortality rates at Canada's environmental water quality guideline concentrations. We used a three-dimensional response surface isobole model-based approach to compare the observed co-toxicity in juvenile amphipods to predicted outcomes based on concentration addition or effects addition mixtures models. More-than-additive lethality was observed for all Cu-PHE, Cu-PHQ, and several Cd-PHE, Cd-PHQ, and Ni-PHE mixtures. Our analysis predicts Cu-PHE, Cu-PHQ, Cd-PHE, and Cd-PHQ mixtures at the Canadian Water Quality Guideline concentrations would produce 7.5%, 3.7%, 4.4% and 1.4% mortality, respectively.

Propeller noise caused by blade tip radial forces

NASA Technical Reports Server (NTRS)

Hanson, D. B.

1986-01-01

New experimental evidence which indicates the presence of leading edge and tip edge vortex flow on Prop-Fans is examined, and performance and noise consequences are addressed. It was shown that the tip edge vortex is a significant noise source, particularly for unswept Prop-Fan blades. Preliminary calculations revealed that the addition of the tip side edge source to single rotation Prop-Fans during take off conditions improved the agreement between experiment and theory at blade passing frequency. At high-speed conditions such as the Prop-Fan cruise point, the tip loading effect tends to cancel thickness noise.

Dark-soliton dynamics in Bose-Einstein condensates at finite temperature

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

Jackson, B.; Proukakis, N. P.; Barenghi, C. F.

2007-05-15

The dynamics of a dark soliton in an elongated Bose-Einstein condensate is studied at finite temperatures. In addition to accurately reproducing all stages of the decay of the soliton observed in the experiment of Burger et al. [Phys. Rev. Lett. 83, 5198 (1999)], our numerical simulations reveal the existence of an experimentally accessible parameter regime for which phase-imprinted dark solitons can execute at least one full axial oscillation prior to their decay. The dependence of the decay time scale on temperature and initial soliton depth is analyzed and the role of interatomic collisions quantified.

Investigations on the in vitro bioactivity of swift heavy oxygen ion irradiated hydroxyapatite.

PubMed

Suganthi, R V; Prakash Parthiban, S; Elayaraja, K; Girija, E K; Kulariya, P; Katharria, Y S; Singh, F; Asokan, K; Kanjilal, D; Narayana Kalkura, S

2009-12-01

The effect of swift heavy oxygen ion irradiation of hydroxyapatite on its in vitro bioactivity was studied. The irradiation experiment was performed using oxygen ions at energy of 100 MeV with 1 x 10(12) and 1 x 10(13) ions/cm2 fluence range. The irradiated samples were characterized by glancing angle X-ray diffraction (GXRD), photoluminescence spectroscopy (PL) and scanning electron microscopy (SEM). GXRD showed that irradiated samples exhibited better crystallinity. The irradiated samples revealed an increase in PL intensity. In addition, the irradiated hydroxyapatite was found to have enhanced bioactivity.

Stacking-fault nucleation on Ir(111).

PubMed

Busse, Carsten; Polop, Celia; Müller, Michael; Albe, Karsten; Linke, Udo; Michely, Thomas

2003-08-01

Variable temperature scanning tunneling microscopy experiments reveal that in Ir(111) homoepitaxy islands nucleate and grow both in the regular fcc stacking and in the faulted hcp stacking. Analysis of this effect in dependence on deposition temperature leads to an atomistic model of stacking-fault formation: The large, metastable stacking-fault islands grow by sufficiently fast addition of adatoms to small mobile adatom clusters which occupy in thermal equilibrium the hcp sites with a significant probability. Using parameters derived independently by field ion microscopy, the model accurately describes the results for Ir(111) and is expected to be valid also for other surfaces.

Bulk and surface loss in superconducting transmon qubits

NASA Astrophysics Data System (ADS)

Dial, Oliver; McClure, Douglas T.; Poletto, Stefano; Keefe, G. A.; Rothwell, Mary Beth; Gambetta, Jay M.; Abraham, David W.; Chow, Jerry M.; Steffen, Matthias

2016-04-01

Decoherence of superconducting transmon qubits is purported to be consistent with surface loss from two-level systems on the substrate surface. Here, we present a study of surface loss in transmon devices, explicitly designed to have varying sensitivities to different surface loss contributors. Our experiments also encompass two particular different sapphire substrates, which reveal the onset of a yet unknown additional loss mechanism outside of surface loss for one of the substrates. Tests across different wafers and devices demonstrate substantial variation, and we emphasize the importance of testing large numbers of devices for disentangling different sources of decoherence.

Alumina Handling Dustiness

NASA Astrophysics Data System (ADS)

Authier-Martin, Monique

Dustiness of calcined alumina is a major concern, causing undesirable working conditions and serious alumina losses. These losses occur primarily during unloading and handling or pot loading and crust breaking. The handling side of the problem is first addressed. The Perra pulvimeter constitutes a simple and reproducible tool to quantify handling dustiness and yields results in agreement with plant experience. Attempts are made to correlate dustiness with bulk properties (particle size, attrition index, …) for a large number of diverse aluminas. The characterization of the dust generated with the Perra pulvimeter is most revealing. The effect of the addition of E.S.P. dust is also reported.

UV-induced bond modifications in thymine and thymine dideoxynucleotide: structural elucidation of isomers by differential mobility mass spectrometry.

PubMed

St-Jacques, Antony; Anichina, Janna; Schneider, Bradley B; Covey, Thomas R; Bohme, Diethard K

2010-07-15

Differential mobility spectrometry has been applied to reveal the occurrence of isomerization of thymine nucleobase and of thymine dideoxynucleotide d(5'-TT-3') due to bond redisposition induced by UV irradiation at 254 nm of frozen aqueous solutions of these molecules. Collision-induced dissociation (CID) spectra of electrosprayed photoproducts of the thymine solution suggest the presence of two isomers (the so-called cyclobutane and 6,4-photoproducts) in addition to the proton-bound thymine dimer, and these were separated using differential mobility spectrometry/mass spectrometry (DMS/MS) techniques with water as the modifier. Similar experiments with d(5'-TT-3') revealed the formation of a new isomer of deprotonated thymine dideoxynucleotide upon UV irradiation that was easily distinguished using DMS/MS with isopropanol as the modifier. The results reinforce the usefulness of DMS/MS in isomer separation.

Microstructures define melting of molybdenum at high pressures

NASA Astrophysics Data System (ADS)

Hrubiak, Rostislav; Meng, Yue; Shen, Guoyin

2017-03-01

High-pressure melting anchors the phase diagram of a material, revealing the effect of pressure on the breakdown of the ordering of atoms in the solid. An important case is molybdenum, which has long been speculated to undergo an exceptionally steep increase in melting temperature when compressed. On the other hand, previous experiments showed nearly constant melting temperature as a function of pressure, in large discrepancy with theoretical expectations. Here we report a high-slope melting curve in molybdenum by synchrotron X-ray diffraction analysis of crystalline microstructures, generated by heating and subsequently rapidly quenching samples in a laser-heated diamond anvil cell. Distinct microstructural changes, observed at pressures up to 130 gigapascals, appear exclusively after melting, thus offering a reliable melting criterion. In addition, our study reveals a previously unsuspected transition in molybdenum at high pressure and high temperature, which yields highly textured body-centred cubic nanograins above a transition temperature.

Functional dynamics of cell surface membrane proteins

NASA Astrophysics Data System (ADS)

Nishida, Noritaka; Osawa, Masanori; Takeuchi, Koh; Imai, Shunsuke; Stampoulis, Pavlos; Kofuku, Yutaka; Ueda, Takumi; Shimada, Ichio

2014-04-01

Cell surface receptors are integral membrane proteins that receive external stimuli, and transmit signals across plasma membranes. In the conventional view of receptor activation, ligand binding to the extracellular side of the receptor induces conformational changes, which convert the structure of the receptor into an active conformation. However, recent NMR studies of cell surface membrane proteins have revealed that their structures are more dynamic than previously envisioned, and they fluctuate between multiple conformations in an equilibrium on various timescales. In addition, NMR analyses, along with biochemical and cell biological experiments indicated that such dynamical properties are critical for the proper functions of the receptors. In this review, we will describe several NMR studies that revealed direct linkage between the structural dynamics and the functions of the cell surface membrane proteins, such as G-protein coupled receptors (GPCRs), ion channels, membrane transporters, and cell adhesion molecules.

Synthesis, characterization and magnetic properties of MWCNTs decorated with Zn-substituted MnFe2O4 nanoparticles using waste batteries extract

NASA Astrophysics Data System (ADS)

Gabal, M. A.; Al-Harthy, E. A.; Al Angari, Y. M.; Abdel Salam, M.; Asiri, A. M.

2016-06-01

Mn1-xZnxFe2O4 (x=0.2-0.8) nano-crystals, synthesized from recycling of Zn-C batteries, were successfully self-assembled alongside multi-walled carbon nanotubes (MWCNTs) via an environmentally friend sucrose auto-combustion method. The effect of Zn-content on structural and magnetic properties were investigated and discussed. XRD revealed the formation of single-phase ferrites. DTA-TG experiment showed that the auto-combustion reaction finished at about 350 °C. TEM exhibited that the MWCNTs are well decorated with ferrite particles. Hysteresis loop measurements revealed ferromagnetic behavior, with saturation magnetization decrease by the addition of MWCNTs or increasing Zn-Content. The kinetics of methylene blue dye (MB) removal using MWCNTs/Mn0.8Zn0.2Fe2O nano-composite was investigated and discussed.

An experimental analysis of harmful algae-zooplankton interactions and the ultimate defense

USGS Publications Warehouse

Remmel, E.J.; Kohmescher, N.; Larson, J.H.; Hambright, K.D.

2011-01-01

We examined effects of the invasive, toxigenic haptophyte Prymnesium parvum on grazing rates, feeding behaviors, and life-history characteristics of clonal lineages of three daphniid zooplankton species. Grazing experiments revealed similar clearance rates for P. parvum and a common green alga. Behavioral observations revealed no significant effects of P. parvum on daphniid feeding behaviors after 30 min, but major declines in appendage beat rates after 1 h. Chronic exposure (10 d) to P. parvum resulted in severe reductions in daphniid growth rates, age at first reproduction, fecundity, and survivorship at densities as low as 7750 cells mL-1. Thus, in addition to direct fish mortality during P. parvum blooms of 50,000-200,000 cells mL-1, the entire food web of an invaded system may be subjected to potentially severe negative consequences even at nonbloom densities of P. parvum. ?? 2011, by the American Society of Limnology and Oceanography, Inc.

Synergistic adhesion mechanisms of spider capture silk.

PubMed

Guo, Yang; Chang, Zheng; Guo, Hao-Yuan; Fang, Wei; Li, Qunyang; Zhao, Hong-Ping; Feng, Xi-Qiao; Gao, Huajian

2018-03-01

It is well known that capture silk, the main sticky component of the orb web of a spider, plays an important role in the spider's ability to capture prey via adhesion. However, the detailed mechanism with which the spider achieves its unparalleled high-adhesion performance remains elusive. In this work, we combine experiments and theoretical analysis to investigate the adhesion mechanisms of spider silk. In addition to the widely recognized adhesion effect of the sticky glue, we reveal a synergistic enhancement mechanism due to the elasticity of silk fibres. A balance between silk stiffness, strength and glue stickiness is crucial to endow the silk with superior adhesion, as well as outstanding energy absorption capacity and structural robustness. The revealed mechanisms deepen our understanding of the working principles of spider silk and suggest guidelines for biomimetic designs of spider-inspired adhesion and capture devices. © 2018 The Author(s).

Functional dynamics of cell surface membrane proteins.

PubMed

Nishida, Noritaka; Osawa, Masanori; Takeuchi, Koh; Imai, Shunsuke; Stampoulis, Pavlos; Kofuku, Yutaka; Ueda, Takumi; Shimada, Ichio

2014-04-01

Cell surface receptors are integral membrane proteins that receive external stimuli, and transmit signals across plasma membranes. In the conventional view of receptor activation, ligand binding to the extracellular side of the receptor induces conformational changes, which convert the structure of the receptor into an active conformation. However, recent NMR studies of cell surface membrane proteins have revealed that their structures are more dynamic than previously envisioned, and they fluctuate between multiple conformations in an equilibrium on various timescales. In addition, NMR analyses, along with biochemical and cell biological experiments indicated that such dynamical properties are critical for the proper functions of the receptors. In this review, we will describe several NMR studies that revealed direct linkage between the structural dynamics and the functions of the cell surface membrane proteins, such as G-protein coupled receptors (GPCRs), ion channels, membrane transporters, and cell adhesion molecules. Copyright © 2013 Elsevier Inc. All rights reserved.

Microstructures define melting of molybdenum at high pressures

PubMed Central

Hrubiak, Rostislav; Meng, Yue; Shen, Guoyin

2017-01-01

High-pressure melting anchors the phase diagram of a material, revealing the effect of pressure on the breakdown of the ordering of atoms in the solid. An important case is molybdenum, which has long been speculated to undergo an exceptionally steep increase in melting temperature when compressed. On the other hand, previous experiments showed nearly constant melting temperature as a function of pressure, in large discrepancy with theoretical expectations. Here we report a high-slope melting curve in molybdenum by synchrotron X-ray diffraction analysis of crystalline microstructures, generated by heating and subsequently rapidly quenching samples in a laser-heated diamond anvil cell. Distinct microstructural changes, observed at pressures up to 130 gigapascals, appear exclusively after melting, thus offering a reliable melting criterion. In addition, our study reveals a previously unsuspected transition in molybdenum at high pressure and high temperature, which yields highly textured body-centred cubic nanograins above a transition temperature. PMID:28248309

Using a cross section to train veterinary students to visualize anatomical structures in three dimensions

NASA Astrophysics Data System (ADS)

Provo, Judy; Lamar, Carlton; Newby, Timothy

2002-01-01

A cross section was used to enhance three-dimensional knowledge of anatomy of the canine head. All veterinary students in two successive classes (n = 124) dissected the head; experimental groups also identified structures on a cross section of the head. A test assessing spatial knowledge of the head generated 10 dependent variables from two administrations. The test had content validity and statistically significant interrater and test-retest reliability. A live-dog examination generated one additional dependent variable. Analysis of covariance controlling for performance on course examinations and quizzes revealed no treatment effect. Including spatial skill as a third covariate revealed a statistically significant effect of spatial skill on three dependent variables. Men initially had greater spatial skill than women, but spatial skills were equal after 8 months. A qualitative analysis showed the positive impact of this experience on participants. Suggestions for improvement and future research are discussed.

Carrot Juice Fermentations as Man-Made Microbial Ecosystems Dominated by Lactic Acid Bacteria.

PubMed

Wuyts, Sander; Van Beeck, Wannes; Oerlemans, Eline F M; Wittouck, Stijn; Claes, Ingmar J J; De Boeck, Ilke; Weckx, Stefan; Lievens, Bart; De Vuyst, Luc; Lebeer, Sarah

2018-06-15

Spontaneous vegetable fermentations, with their rich flavors and postulated health benefits, are regaining popularity. However, their microbiology is still poorly understood, therefore raising concerns about food safety. In addition, such spontaneous fermentations form interesting cases of man-made microbial ecosystems. Here, samples from 38 carrot juice fermentations were collected through a citizen science initiative, in addition to three laboratory fermentations. Culturing showed that Enterobacteriaceae were outcompeted by lactic acid bacteria (LAB) between 3 and 13 days of fermentation. Metabolite-target analysis showed that lactic acid and mannitol were highly produced, as well as the biogenic amine cadaverine. High-throughput 16S rRNA gene sequencing revealed that mainly species of Leuconostoc and Lactobacillus (as identified by 8 and 20 amplicon sequence variants [ASVs], respectively) mediated the fermentations in subsequent order. The analyses at the DNA level still detected a high number of Enterobacteriaceae , but their relative abundance was low when RNA-based sequencing was performed to detect presumptive metabolically active bacterial cells. In addition, this method greatly reduced host read contamination. Phylogenetic placement indicated a high LAB diversity, with ASVs from nine different phylogenetic groups of the Lactobacillus genus complex. However, fermentation experiments with isolates showed that only strains belonging to the most prevalent phylogenetic groups preserved the fermentation dynamics. The carrot juice fermentation thus forms a robust man-made microbial ecosystem suitable for studies on LAB diversity and niche specificity. IMPORTANCE The usage of fermented food products by professional chefs is steadily growing worldwide. Meanwhile, this interest has also increased at the household level. However, many of these artisanal food products remain understudied. Here, an extensive microbial analysis was performed of spontaneous fermented carrot juices which are used as nonalcoholic alternatives for wine in a Belgian Michelin star restaurant. Samples were collected through an active citizen science approach with 38 participants, in addition to three laboratory fermentations. Identification of the main microbial players revealed that mainly species of Leuconostoc and Lactobacillus mediated the fermentations in subsequent order. In addition, a high diversity of lactic acid bacteria was found; however, fermentation experiments with isolates showed that only strains belonging to the most prevalent lactic acid bacteria preserved the fermentation dynamics. Finally, this study showed that the usage of RNA-based 16S rRNA amplicon sequencing greatly reduces host read contamination. Copyright © 2018 American Society for Microbiology.

The relative effects on math performance of single- versus multiple-ratio schedules: a case study1

PubMed Central

Lovitt, Tom C.; Esveldt, Karen A.

1970-01-01

This series of four experiments sought to assess the comparative effects of multiple- versus single-ratio schedules on a pupil's responding to mathematics materials. Experiment I, which alternated between single- and multiple-ratio contingencies, revealed that during the latter phase the subject responded at a higher rate. Similar findings were revealed by Exp. II. The third experiment, which manipulated frequency of reinforcement rather than multiple ratios, revealed that the alteration had a minimal effect on the subject's response rate. A final experiment, conducted to assess further the effects of multiple ratios, provided data similar to those of Exp. I and II. PMID:16795267

Mechanism and scope of the cyanide-catalyzed cross silyl benzoin reaction.

PubMed

Linghu, Xin; Bausch, Cory C; Johnson, Jeffrey S

2005-02-16

In this work, cross silyl benzoin addition reactions between acylsilanes (1) and aldehydes (2) catalyzed by metal cyanides are described. Unsymmetrical aryl-, heteroaryl-, and alkyl-substituted benzoin adducts can be generated in moderate to excellent yields with complete regiocontrol using potassium cyanide and a phase transfer catalyst. From a screen of transition metal cyanide complexes, lanthanum tricyanide was identified as an improved second-generation catalyst for the cross silyl benzoin reaction. A study of the influence of water on the KCN-catalyzed cross silyl benzoin addition revealed more practical reaction conditions using unpurified solvent under ambient conditions. A sequential silyl benzoin addition/cyanation/O-acylation reaction that resulted in two new C-C bonds was achieved in excellent yield. The mechanism of cross silyl benzoin addition is proposed in detail and is supported by crossover studies and a number of unambiguous experiments designed to ascertain the reversibility of key steps. No productive chemistry arises from cyanation of the more electrophilic aldehyde component. Formation of the carbon-carbon bond is shown to be the last irreversible step in the reaction.

Combination of RNA interference and virus receptor trap exerts additive antiviral activity in coxsackievirus B3-induced myocarditis in mice.

PubMed

Stein, Elisabeth A; Pinkert, Sandra; Becher, Peter Moritz; Geisler, Anja; Zeichhardt, Heinz; Klopfleisch, Robert; Poller, Wolfgang; Tschöpe, Carsten; Lassner, Dirk; Fechner, Henry; Kurreck, Jens

2015-02-15

Coxsackievirus B3 (CVB3) is a major heart pathogen against which no therapy exists to date. The potential of a combination treatment consisting of a proteinaceous virus receptor trap and an RNA interference-based component to prevent CVB3-induced myocarditis was investigated. A soluble variant of the extracellular domain of the coxsackievirus-adenovirus receptor (sCAR-Fc) was expressed from an adenoviral vector and 2 short hairpin RNAs (shRdRp2.4) directed against CVB3 were delivered by an adeno-associated virus (AAV) vector. Cell culture experiments revealed additive antiviral activity of the combined application. In a CVB3-induced mouse myocarditis model, both components applied individually significantly reduced inflammation and viral load in the heart. The combination exerted an additive antiviral effect and reduced heart pathology. Hemodynamic measurement revealed that infection with CVB3 resulted in impaired heart function, as illustrated by a drastically reduced cardiac output and impaired contractility and relaxation. Treatment with either sCAR-Fc or shRdRp2.4 significantly improved these parameters. Importantly, the combination of both components led to a further significant improvement of heart function. Combination of sCAR-Fc and shRdRp2.4 exerted additive effects and was significantly more effective than either of the single treatments in inhibiting CVB3-induced myocarditis and preventing cardiac dysfunction. © The Author 2014. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Revealing nonergodic dynamics in living cells from a single particle trajectory

NASA Astrophysics Data System (ADS)

Lanoiselée, Yann; Grebenkov, Denis S.

2016-05-01

We propose the improved ergodicity and mixing estimators to identify nonergodic dynamics from a single particle trajectory. The estimators are based on the time-averaged characteristic function of the increments and can thus capture additional information on the process as compared to the conventional time-averaged mean-square displacement. The estimators are first investigated and validated for several models of anomalous diffusion, such as ergodic fractional Brownian motion and diffusion on percolating clusters, and nonergodic continuous-time random walks and scaled Brownian motion. The estimators are then applied to two sets of earlier published trajectories of mRNA molecules inside live Escherichia coli cells and of Kv2.1 potassium channels in the plasma membrane. These statistical tests did not reveal nonergodic features in the former set, while some trajectories of the latter set could be classified as nonergodic. Time averages along such trajectories are thus not representative and may be strongly misleading. Since the estimators do not rely on ensemble averages, the nonergodic features can be revealed separately for each trajectory, providing a more flexible and reliable analysis of single-particle tracking experiments in microbiology.

Root Growth Patterns and Morphometric Change Based on the Growth Media

NASA Astrophysics Data System (ADS)

Schultz, Eric R.; Paul, Anna-Lisa; Ferl, Robert J.

2016-12-01

Arabidopsis thaliana roots skew with minimal waving in the microgravity environment of the International Space Station. Root skewing and root waving have been studied on the ground as well as in spaceflight, but often using different media types. In this study, Arabidopsis seedlings were grown on nutrient media plates that were comprised of various gelling agents with varied hardness in order to better assess these media for spaceflight research experiments. ImageJ was used to quantify the root morphology of 8-dayold seedlings, while R was used to perform statistical analyses. Root growth was drastically different between Difco agar, agarose, and Phytagel. Additionally, root waving masked skewing in certain media. Regression analysis revealed overall patterns when organized by hardness but also revealed that differences in media type had more of an impact on root growth than hardness itself. Different arrangements of media around the root tip revealed that roots grown on the media surface were longer and had fewer waves per millimeter than roots grown embedded in media. The implications for spaceflight research are discussed.

Know your neighbor: The impact of social context on fairness behavior

PubMed Central

2018-01-01

Laboratory experiments offer an opportunity to isolate human behaviors with a level of precision that is often difficult to obtain using other (survey-based) methods. Yet, experimental tasks are often stripped of any social context, implying that inferences may not directly map to real world contexts. We randomly allocate 632 individuals (grouped randomly into 316 dyads) from small villages in Sierra Leone to four versions of the ultimatum game. In addition to the classic ultimatum game, where both the sender and receiver are anonymous, we reveal the identity of the sender, the receiver or both. This design allows us to explore how fairness behavior is affected by social context in a natural setting where players are drawn from populations that are well-acquainted. We find that average offers increase when the receiver’s identity is revealed, suggesting that anonymous ultimatum games underestimate expected fair offers. This study suggest that researchers wishing to relate laboratory behavior to contexts in which the participants are well-acquainted should consider revealing the identities of the players during game play. PMID:29641584

Characterization of the high affinity binding of epsilon toxin from Clostridium perfringens to the renal system.

PubMed

Dorca-Arévalo, Jonatan; Martín-Satué, Mireia; Blasi, Juan

2012-05-25

Epsilon toxin (ε-toxin), produced by Clostridium perfringens types B and D, causes fatal enterotoxaemia in livestock. In the renal system, the toxin binds to target cells before oligomerization, pore formation and cell death. Still, there is little information about the cellular and molecular mechanism involved in the initial steps of the cytotoxic action of ε-toxin, including the specific binding to the target sensitive cells. In the present report, the binding step of ε-toxin to the MDCK cell line is characterized by means of an ELISA-based binding assay with recombinant ε-toxin-green fluorescence protein (ε-toxin-GFP) and ε-prototoxin-GFP. In addition, different treatments with Pronase E, detergents, N-glycosidase F and beta-elimination on MDCK cells and renal cryosections have been performed to further characterize the ε-toxin binding. The ELISA assays revealed a single binding site with a similar dissociation constant (K(d)) for ε-toxin-GFP and ε-prototoxin-GFP, but a three-fold increase in B(max) levels in the case of ε-toxin-GFP. Double staining on kidney cryoslices with lectins and ε-prototoxin-GFP revealed specific binding to distal and collecting tubule cells. In addition, experiments on kidney and bladder cryoslices demonstrated the specific binding to distal tubule of a range of mammalian renal systems. Pronase E and beta-elimination treatments on kidney cryoslices and MDCK cells revealed that the binding of ε-toxin in renal system is mediated by a O-glycoprotein. Detergent treatments revealed that the integrity of the plasma membrane is required for the binding of ε-toxin to its receptor. Copyright © 2011 Elsevier B.V. All rights reserved.

Results of the Baikal Experiment on Observations of Macroscopic Nonlocal Correlations in Reverse Time

NASA Astrophysics Data System (ADS)

Korotaev, S. M.; Serdyuk, V. O.; Kiktenko, E. O.; Budnev, N. M.; Gorohov, J. V.

Although the general theory macroscopic quantum entanglement of is still in its infancy, consideration of the matter in the framework of action-at-a distance electrodynamics predicts for the random dissipative processes observability of the advanced nonlocal correlations (time reversal causality). These correlations were really revealed in our previous experiments with some large-scale heliogeophysical processes as the source ones and the lab detectors as the probe ones. Recently a new experiment has been performing on the base of Baikal Deep Water Neutrino Observatory. The thick water layer is an excellent shield against any local impacts on the detectors. The first annual series 2012/2013 has demonstrated that detector signals respond to the heliogeophysical (external) processes and causal connection of the signals directed downwards: from the Earth surface to the Baikal floor. But this nonlocal connection proved to be in reverse time. In addition advanced nonlocal correlation of the detector signal with the regional source-process: the random component of hydrological activity in the upper layer was revealed and the possibility of its forecast on nonlocal correlations was demonstrated. But the strongest macroscopic nonlocal correlations are observed at extremely low frequencies, that is at periods of several months. Therefore the above results should be verified in a longer experiment. We verify them by data of the second annual series 2013/2014 of the Baikal experiment. All the results have been confirmed, although some quantitative parameters of correlations and time reversal causal links turned out different due to nonstationarity of the source-processes. A new result is displaying of the advanced response of nonlocal correlation detector to the earthquake. This opens up the prospect of the earthquake forecast on the new physical principle, although further confirmation in the next events is certainly needed. The continuation of the Baikal experiment with expanded program is burning.

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

Baumann, Philipp; Mandl-Weber, Sonja; Oduncu, Fuat

NVP-BEZ235 is a new inhibitor of phosphoinositol-3-kinase (PI3 kinase) and mammalian target of rapamycin (mTOR) whose efficacy in advanced solid tumours is currently being evaluated in a phase I/II clinical trial. Here we show that NVP-BEZ235 inhibits growth in common myeloma cell lines as well as primary myeloma cells at nanomolar concentrations in a time and dose dependent fashion. Further experiments revealed induction of apoptosis in three of four cell lines. Inhibition of cell growth was mainly due to inhibition of myeloma cell proliferation, as shown by the BrdU assay. Cell cycle analysis revealed induction of cell cycle arrest inmore » the G1 phase, which was due to downregulation of cyclin D1, pRb and cdc25a. NVP-BEZ235 inhibited phosphorylation of protein kinase B (Akt), P70S6k and 4E-BP-1. Furthermore we show that the stimulatory effect of CD40-ligand (CD40L), insulin-like growth factor 1 (IGF-1), interleukin-6 (IL-6) and conditioned medium of HS-5 stromal cells on myeloma cell growth is completely abrogated by NVP-BEZ235. In addition, synergism studies revealed synergistic and additive activity of NVP-BEZ235 together with melphalan, doxorubicin and bortezomib. Taken together, inhibition of PI3 kinase/mTOR by NVP-BEZ235 is highly effective and NVP-BEZ235 represents a potential new candidate for targeted therapy in multiple myeloma.« less

Application of hydroxyapatite nanoparticles in development of an enhanced formulation for delivering sustained release of triamcinolone acetonide

PubMed Central

Koocheki, Saeid; Madaeni, Sayed Siavash; Niroomandi, Parisa

2011-01-01

We report an analysis of in vitro and in vivo drug release from an in situ formulation consisting of triamcinolone acetonide (TR) and poly(d,l-lactide-co-glycolide) (PLGA) and the additives glycofurol (GL) and hydroxyapatite nanoparticles (HA). We found that these additives enhanced drug release rate. We used the Taguchi method to predict optimum formulation variables to minimize the initial burst. This method decreased the burst rate from 8% to 1.3%. PLGA-HA acted as a strong buffer, thereby preventing tissue inflammation at the injection site caused by the acidic degradation products of PLGA. Characterization of the optimized formulation by a variety of techniques, including scanning electron microscopy, X-ray diffraction, differential scanning calorimetry, and Fourier transform near infrared spectroscopy, revealed that the crystalline structure of TR was converted to an amorphous form. Therefore, this hydrophobic agent can serve as an additive to modify drug release rates. Data generated by in vitro and in vivo experiments were in good agreement. PMID:21589650

Getting connected: Both associative and semantic links structure semantic memory for newly learned persons.

PubMed

Wiese, Holger; Schweinberger, Stefan R

2015-01-01

The present study examined whether semantic memory for newly learned people is structured by visual co-occurrence, shared semantics, or both. Participants were trained with pairs of simultaneously presented (i.e., co-occurring) preexperimentally unfamiliar faces, which either did or did not share additionally provided semantic information (occupation, place of living, etc.). Semantic information could also be shared between faces that did not co-occur. A subsequent priming experiment revealed faster responses for both co-occurrence/no shared semantics and no co-occurrence/shared semantics conditions, than for an unrelated condition. Strikingly, priming was strongest in the co-occurrence/shared semantics condition, suggesting additive effects of these factors. Additional analysis of event-related brain potentials yielded priming in the N400 component only for combined effects of visual co-occurrence and shared semantics, with more positive amplitudes in this than in the unrelated condition. Overall, these findings suggest that both semantic relatedness and visual co-occurrence are important when novel information is integrated into person-related semantic memory.

Metallophosphite-Catalyzed Asymmetric Acylation of α,β -Unsaturated Amides

PubMed Central

Nahm, Mary R.; Potnick, Justin R.; White, Peter S.; Johnson, Jeffrey S.

2007-01-01

The l-menthone-derived TADDOL phosphite 6b catalyzes highly enantioselective conjugate additions of acyl silanes to α,β-unsaturated amides. p-Methoxybenzoyl cyclohexyldimethylsilane adds to a variety of N,N-dimethyl acrylamide derivatives in the presence of the lithium salt of 6b. In many instances the α-silyl-γ-ketoamide product undergoes facile enantioenrichment (to 97–99% ee) upon recrystallization. Desilylation with HF·pyr affords the formal Stetter addition products. Baeyer–Villiger oxidation of the desilylated γ-ketoamides affords useful ester products. An X-ray diffraction study of 6b reveals that the isopropyl group of the menthone ketal influences the position of the syn-pseudoaxial phenyl group in the TADDOL structure. Through a crossover experiment, the silicon migration step in the reaction mechanism is shown to be strictly intramolecular. PMID:16492064

Valley Vortex States in Sonic Crystals

NASA Astrophysics Data System (ADS)

Lu, Jiuyang; Qiu, Chunyin; Ke, Manzhu; Liu, Zhengyou

2016-03-01

Valleytronics is quickly emerging as an exciting field in fundamental and applied research. In this Letter, we study the acoustic version of valley states in sonic crystals and reveal a vortex nature of such states. In addition to the selection rules established for exciting valley polarized states, a mimicked valley Hall effect of sound is proposed further. The extraordinary chirality of valley vortex states, detectable in experiments, may open a new possibility in sound manipulations. This is appealing to scalar acoustics that lacks a spin degree of freedom inherently. In addition, the valley selection enables a handy way to create vortex matter in acoustics, in which the vortex chirality can be controlled flexibly. Potential applications can be anticipated with the exotic interaction of acoustic vortices with matter, such as to trigger the rotation of the trapped microparticles without contact.

The Toxic Effects of Cigarette Additives. Philip Morris' Project Mix Reconsidered: An Analysis of Documents Released through Litigation

PubMed Central

Wertz, Marcia S.; Kyriss, Thomas; Paranjape, Suman; Glantz, Stanton A.

2011-01-01

Background In 2009, the promulgation of US Food and Drug Administration (FDA) tobacco regulation focused attention on cigarette flavor additives. The tobacco industry had prepared for this eventuality by initiating a research program focusing on additive toxicity. The objective of this study was to analyze Philip Morris' Project MIX as a case study of tobacco industry scientific research being positioned strategically to prevent anticipated tobacco control regulations. Methods and Findings We analyzed previously secret tobacco industry documents to identify internal strategies for research on cigarette additives and reanalyzed tobacco industry peer-reviewed published results of this research. We focused on the key group of studies conducted by Phillip Morris in a coordinated effort known as “Project MIX.” Documents showed that Project MIX subsumed the study of various combinations of 333 cigarette additives. In addition to multiple internal reports, this work also led to four peer-reviewed publications (published in 2001). These papers concluded that there was no evidence of substantial toxicity attributable to the cigarette additives studied. Internal documents revealed post hoc changes in analytical protocols after initial statistical findings indicated an additive-associated increase in cigarette toxicity as well as increased total particulate matter (TPM) concentrations in additive-modified cigarette smoke. By expressing the data adjusted by TPM concentration, the published papers obscured this underlying toxicity and particulate increase. The animal toxicology results were based on a small number of rats in each experiment, raising the possibility that the failure to detect statistically significant changes in the end points was due to underpowering the experiments rather than lack of a real effect. Conclusion The case study of Project MIX shows tobacco industry scientific research on the use of cigarette additives cannot be taken at face value. The results demonstrate that toxins in cigarette smoke increase substantially when additives are put in cigarettes, including the level of TPM. In particular, regulatory authorities, including the FDA and similar agencies elsewhere, could use the Project MIX data to eliminate the use of these 333 additives (including menthol) from cigarettes. Please see later in the article for the Editors' Summary PMID:22205885

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.

Psychophysical and Neural Correlates of Auditory Attraction and Aversion

NASA Astrophysics Data System (ADS)

Patten, Kristopher Jakob

This study explores the psychophysical and neural processes associated with the perception of sounds as either pleasant or aversive. The underlying psychophysical theory is based on auditory scene analysis, the process through which listeners parse auditory signals into individual acoustic sources. The first experiment tests and confirms that a self-rated pleasantness continuum reliably exists for 20 various stimuli (r = .48). In addition, the pleasantness continuum correlated with the physical acoustic characteristics of consonance/dissonance (r = .78), which can facilitate auditory parsing processes. The second experiment uses an fMRI block design to test blood oxygen level dependent (BOLD) changes elicited by a subset of 5 exemplar stimuli chosen from Experiment 1 that are evenly distributed over the pleasantness continuum. Specifically, it tests and confirms that the pleasantness continuum produces systematic changes in brain activity for unpleasant acoustic stimuli beyond what occurs with pleasant auditory stimuli. Results revealed that the combination of two positively and two negatively valenced experimental sounds compared to one neutral baseline control elicited BOLD increases in the primary auditory cortex, specifically the bilateral superior temporal gyrus, and left dorsomedial prefrontal cortex; the latter being consistent with a frontal decision-making process common in identification tasks. The negatively-valenced stimuli yielded additional BOLD increases in the left insula, which typically indicates processing of visceral emotions. The positively-valenced stimuli did not yield any significant BOLD activation, consistent with consonant, harmonic stimuli being the prototypical acoustic pattern of auditory objects that is optimal for auditory scene analysis. Both the psychophysical findings of Experiment 1 and the neural processing findings of Experiment 2 support that consonance is an important dimension of sound that is processed in a manner that aids auditory parsing and functional representation of acoustic objects and was found to be a principal feature of pleasing auditory stimuli.

Remote distractor effects and saccadic inhibition: spatial and temporal modulation.

PubMed

Walker, Robin; Benson, Valerie

2013-09-12

The onset of a visual distractor remote from a saccade target is known to increase saccade latency (the remote distractor effect [RDE]). In addition, distractors may also selectively inhibit saccades that would be initiated about 90 ms after distractor onset (termed saccadic inhibition [SI]). Recently, it has been proposed that the transitory inhibition of saccades (SI) may underlie the increase in mean latency (RDE). In a first experiment, the distractor eccentricity was manipulated, and a robust RDE that was strongly modulated by distractor eccentricity was observed. However, the underlying latency distributions did not reveal clear evidence of SI. A second experiment manipulated distractor spatial location and the timing of the distractor onset in relation to the target. An RDE was again observed with remote distractors away from the target axis and under conditions with early-onset distractors that would be unlikely to produce SI, whereas later distractor onsets produced an RDE along with some evidence of an SI effect. A third experiment using a mixed block of target-distractor stimulus-onset asynchronies (SOAs) revealed an RDE that varied with both distractor eccentricity and SOA and changes to latency distributions consistent with the timing of SI. We argue that the notion that SI underpins the RDE is similar to the earlier argument that express saccades underlie the fixation offset (gap) effect and that changes in mean latency and to the shape of the underlying latency distributions following a visual onset may involve more than one inhibitory process.

Diverse Seismic Imaging Created by the Seismic Explosion Experiment of the TAIGER Project

NASA Astrophysics Data System (ADS)

Wang, C.; Okaya, D.; Wu, F.; Yen, H.; Huang, B.; Liang, W.

2008-12-01

The TAIGER (TAiwan Integrated GEodynamics Research) project which examines the Taiwan orogeny includes five experiments: natural earthquake recording, man-made explosion recording, Magnetotelluic imaging, marine MCS and sea-land shooting, and deformation evolution modeling. During Feb-Mar 2008, the explosion experiment was carried out. Ten sources with 500~3000kg dynamite were detonated along two transects across northern and southern Taiwan. Over 600 PASSCAL Texans and 40 R-130 instruments record the signals over 100~300 km range. Additional arrays with 100 seismometers were deployed to collect north-south line and fan shoot data for 3D imaging. Furthermore, there are 9 ocean bottom seismometers (OBS) in the Taiwan Strait and two lines with 20 seismometers deployed on the mainland China side. A large volume of qualified data has been created. Except explosion signals, numerous local and regional earthquakes were also recorded even by the Texan instruments. The rich earthquake-explosion dataset now exists at the Institute of Earth Sciences, Academia Sinica operated by the Taiwan Earthquake Center (TEC). Preliminary examination of the data reveal crustal Pg, PmP, Pn and intermediate crustal reflection phases within the transect profiles and in the 3D cross-arrays. These data provide direct seismic imaging of the continental Moho under Taiwan and the sharp Moho root configuration associated with mountain building. Seismic tomography and raytrace methods reveal velocity structure consistent with convergence and vertical exhumation of the Central Ranges.

Biodegradation of Spilled Diesel Fuel in Agricultural Soil: Effect of Humates, Zeolite, and Bioaugmentation

PubMed Central

Kuráň, Pavel; Nováková, Jana; Pilařová, Věra; Dáňová, Petra; Pavlorková, Jana; Kozler, Josef; Novák, František

2014-01-01

Possible enhancement of biodegradation of petroleum hydrocarbons in agricultural soil after tank truck accident (~5000 mg/kg dry soil initial concentration) by bioaugmentation of diesel degrading Pseudomonas fluorescens strain and addition of abiotic additives (humates, zeolite) was studied in a 9-month pot experiment. The biodegradation process was followed by means of analytical parameters (hydrocarbon index expressed as content of C10–C40 aliphatic hydrocarbons, ratio pristane/C17, and total organic carbon content) and characterization of soil microbial community (content of phospholipid fatty acids (PLFA) as an indicator of living microbial biomass, respiration, and dehydrogenase activity). The concentration of petroleum hydrocarbons (C10–C40) was successfully reduced by ~60% in all 15 experiment variants. The bioaugmentation resulted in faster hydrocarbon elimination. On the contrary, the addition of humates and zeolite caused only a negligible increase in the degradation rate. These factors, however, affected significantly the amount of PLFA. The humates caused significantly faster increase of the total PLFA suggesting improvement of the soil microenvironment. Zeolite caused significantly slower increase of the total PLFA; nevertheless it aided in homogenization of the soil. Comparison of microbial activities and total PLFA revealed that only a small fraction of autochthonous microbes took part in the biodegradation which confirms that bioaugmentation was the most important treatment. PMID:24672346

A comparison of traditional physical laboratory and computer-simulated laboratory experiences in relation to engineering undergraduate students' conceptual understandings of a communication systems topic

NASA Astrophysics Data System (ADS)

Javidi, Giti

2005-07-01

This study was designed to investigate an alternative to the use of traditional physical laboratory activities in a communication systems course. Specifically, this study examined whether as an alternative, computer simulation is as effective as physical laboratory activities in teaching college-level electronics engineering education students about the concepts of signal transmission, modulation and demodulation. Eighty undergraduate engineering students participated in the study, which was conducted at a southeastern four-year university. The students were randomly assigned to two groups. The groups were compared on understanding the concepts, remembering the concepts, completion time of the lab experiments and perception toward the laboratory experiments. The physical group's (n = 40) treatment was to conduct laboratory experiments in a physical laboratory. The students in this group used equipment in a controlled electronics laboratory. The Simulation group's (n = 40) treatment was to conduct similar experiments in a PC laboratory. The students in this group used a simulation program in a controlled PC lab. At the completion of the treatment, scores on a validated conceptual test were collected once after the treatment and again three weeks after the treatment. Attitude surveys and qualitative study were administered at the completion of the treatment. The findings revealed significant differences, in favor of the simulation group, between the two groups on both the conceptual post-test and the follow-up test. The findings also revealed significant correlation between simulation groups' attitude toward the simulation program and their post-test scores. Moreover, there was a significant difference between the two groups on their attitude toward their laboratory experience in favor of the simulation group. In addition, there was significant difference between the two groups on their lab completion time in favor of the simulation group. At the same time, the qualitative research has uncovered several issues not explored by the quantitative research. It was concluded that incorporating the recommendations acquired from the qualitative research, especially elements of incorporating hardware experience to avoid lack of hands-on skills, into the laboratory pedagogy should help improve students' experience regardless of the environment in which the laboratory is conducted.

Duration of senescent cell survival in vitro as a characteristic of organism longevity, an additional to the proliferative potential of fibroblasts.

PubMed

Yegorov, Yegor E; Zelenin, Alexander V

2003-04-24

More than 40 years have passed since the original publication by Hayflick and Moorhead led to the concept of the 'Hayflick limit' of the maximum number of divisions which somatic cells undergo in vitro. This concept is still regarded as a fundamental characteristic of species longevity. Here we want to emphasize another characteristic of somatic cells, namely, the duration of their survival in vitro in the non-dividing state after cessation of proliferation. This is suggested on the basis of results of recent experiments with so-called Japanese accelerated senescent mice. Results of these experiments reveal a good correlation between the longevity of the mice, the number of duplications of their fibroblasts in vitro, and the survival time of these cells in the non-dividing state. In routine culture conditions, cell survival time may be very long, as much as a few years. However, when the cells are grown under conditions of oxidative stress, cellular longevity is markedly shortened. This new test may serve as an additional marker of organismic longevity. The comparative value of both tests, the classical 'Hayflick limit' and the new test, is discussed.

Electrochemical oxidation of tramadol in low-salinity reverse osmosis concentrates using boron-doped diamond anodes.

PubMed

Lütke Eversloh, Christian; Schulz, Manoj; Wagner, Manfred; Ternes, Thomas A

2015-04-01

The electrochemical treatment of low-salinity reverse osmosis (RO) concentrates was investigated using tramadol (100 μM) as a model substance for persistent organic contaminants. Galvanostatic degradation experiments using boron-doped diamond electrodes at different applied currents were conducted in RO concentrates as well as in ultra-pure water containing either sodium chloride or sodium sulfate. Kinetic investigations revealed a significant influence of in-situ generated active chlorine besides direct anodic oxidation. Therefore, tramadol concentrations decreased more rapidly at elevated chloride content. Nevertheless, reduction of total organic carbon (TOC) was found to be comparatively low, demonstrating that transformation rather than mineralization was taking place. Early stage product formation could be attributed to both direct and indirect processes, including demethylation, hydroxylation, dehydration, oxidative aromatic ring cleavage and halogenation reactions. The latter led to various halogenated derivatives and resulted in AOX (adsorbable organic halogens) formation in the lower mg/L-range depending on the treatment conditions. Characterisation of transformation products (TPs) was achieved via MS(n) experiments and additional NMR measurements. Based on identification and quantification of the main TPs in different matrices and on additional potentiostatic electrolysis, a transformation pathway was proposed. Copyright © 2014 Elsevier Ltd. All rights reserved.

Physiological effects of an additional stressor on fish exposed to a simulated heavy-metal-containing effluent from a sulfide ore smeltery

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

Larsson, A.; Haux, C.; Sjoebeck, M.L.

1984-04-01

Perches (Perca fluviatilis), kept in slightly hypotonic brackish water, were exposed to dilutions of a simulated heavy-metal-containing effluent from a sulfide ore smeltery . Biochemical and hematological effects of the effluent, as well as the metal residues in liver and muscle tissues, were investigated after 12 and 27 days of exposure. The metal analyses revealed no significant uptake of metals in liver and muscle during the experiment. In spite of this, the exposed fish showed several physiological effects. Some of these, e.g., anemia, hypocalcemia, increased muscle water content, and reduced liver size, were of a transient nature, while others, suchmore » as disturbed chloride balance and hyperglycemia, seemed to be more persistent. At the end of the experiment (29-33 days of exposure), the physiological response to stress treatment (asphyxia) and a subsequent recovery were studied in exposed and unexposed fish. This stress investigation indicates that an additional stressor may strengthen the toxic effects of the heavy-metal-containing effluent. Furthermore, the secondary stress responses were more pronounced and the ability to recover from them seemed to be impaired in exposed fish as compared to unexposed fish.« less

Cognitive aspects of sexual functioning: differences between East Asian-Canadian and Euro-Canadian women.

PubMed

Morton, Heather; Gorzalka, Boris B

2013-11-01

The purpose of this study was to investigate the sexual beliefs of female undergraduates, as well as the thoughts they experience during sexual experiences. The study aimed to determine potential differences in these variables between East Asian-Canadians and Euro-Canadians, as well as the influence of acculturation on these variables. In addition, the relationships between sexual beliefs, automatic thoughts, and specific aspects of sexual functioning were examined. Euro-Canadian (n = 77) and East Asian-Canadian (n = 123) undergraduate women completed the Sexual Dysfunctional Beliefs Questionnaire, the Sexual Modes Questionnaire, the Female Sexual Function Index, and the Vancouver Index of Acculturation. East Asian women endorsed almost all sexual beliefs assessed in this study more than did Euro-Canadian women, and endorsement of these beliefs was associated with acculturation. In addition, East Asian-Canadian and Euro-Canadian women differed in the frequency of experiencing negative automatic thoughts. Results also revealed associations between difficulties in sexual functioning, and both sexual beliefs and automatic thoughts. Together, these results provide preliminary support for the hypothesis that differences in cognitive aspects of sexuality may underlie the differences in sexual functioning previously observed between these two groups.

Characterisation of clinically isolated Streptococcus pyogenes from balanoposthitis patients, with special emphasis on emm89 isolates.

PubMed

Hasegawa, Tadao; Hata, Nanako; Matsui, Hideyuki; Isaka, Masanori; Tatsuno, Ichiro

2017-04-01

Streptococcus pyogenes causes a variety of diseases, such as pharyngitis and toxic shock syndrome. In addition, this bacterium is a causative agent of balanoposthitis. To reveal the bacteriological characteristics of the isolates from balanoposthitis patients, we analysed 47 isolates. In addition, novel clade genotype emm89 S. pyogenes isolates have been reported to be spreading worldwide recently. Hence, we further analysed eight emm89 isolates. A drug susceptibility experiment was performed and emm types were determined. More detailed experiments, such as PCR analysis for the presence of virulence-associated genes and MLST analysis, were performed especially using emm89 isolates. All isolates were sensitive to ampicillin, but 34 % of the isolates were resistant to at least one antibiotic. The emm types of the isolates varied, with emm89 and emm11 being the most prevalent, but the emm1 type was not detected. The analysis of emm89 isolates revealed that drug susceptibilities varied. All isolates were negative for the hasABC gene and produced active NADase that are characteristics of novel clade genotype emm89 S. pyogenes. MLST analysis demonstrated that six isolates were of the ST101 type, the most predominant type reported thus far, but two isolates were of the ST646 type. According to the PCR analysis used to determine the presence of streptococcal pyrogenic exotoxin-related genes, the six ST101 isolates were further classified into four groups. These results suggest that balanoposthitis is caused by a variety of types of S. pyogenes, with novel clade genotype emm89 isolates playing a role in balanoposthitis infections in Japan.

CYP2C19 progress curve analysis and mechanism-based inactivation by three methylenedioxyphenyl compounds.

PubMed

Salminen, Kaisa A; Meyer, Achim; Imming, Peter; Raunio, Hannu

2011-12-01

Several in vitro criteria were used to assess whether three methylenedioxyphenyl (MDP) compounds, the isoquinoline alkaloids bulbocapnine, canadine, and protopine, are mechanism-based inactivators of CYP2C19. The recently reported fluorometric CYP2C19 progress curve analysis approach was applied first to determine whether these alkaloids demonstrate time-dependent inhibition. In this experiment, bulbocapnine, canadine, and protopine displayed time dependence and saturation in their inactivation kinetics with K(I) and k(inact) values of 72.4 ± 14.7 μM and 0.38 ± 0.036 min(-1), 2.1 ± 0.63 μM and 0.18 ± 0.015 min(-1), and 7.1 ± 2.3 μM and 0.24 ± 0.021 min(-1), respectively. Additional studies were performed to determine whether other specific criteria for mechanism-based inactivation were fulfilled: NADPH dependence, irreversibility, and involvement of a catalytic step in the enzyme inactivation. CYP2C19 activity was not significantly restored by dialysis when it had been inactivated by the alkaloids in the presence of a NADPH-regenerating system, and a metabolic-intermediate complex-associated increase in absorbance at approximately 455 nm was observed. In conclusion, the CYP2C19 progress curve analysis method revealed time-dependent inhibition by these alkaloids, and additional experiments confirmed its quasi-irreversible nature. This study revealed that the CYP2C19 progress curve analysis method is useful for identifying novel mechanism-based inactivators and yields a wealth of information in one run. The alkaloids bulbocapnine, canadine, and protopine, present in herbal medicines, are new mechanism-based inactivators and the first MDP compounds exhibiting quasi-irreversible inactivation of CYP2C19.

Holos: A collaborative environment for similarity-based holistic approaches.

PubMed

Lê, Tâm Minh; Brard, Margot; Lê, Sébastien

2017-10-01

Through this article, we aim to introduce Holos-a new collaborative environment that allows researchers to carry out experiments based on similarity assessments between stimuli, such as in projective-mapping and sorting tasks. An important feature of Holos is its capacity to assess real-time individual processes during the task. Within the Holos environment, researchers can design experiments on its platform, which can handle four kinds of stimuli: concepts, images, sounds, and videos. In addition, researchers can share their study resources within the scientific community, including stimuli, experimental protocols, and/or the data collected. With a dedicated Android application combined with a tactile human-machine interface, subjects can perform experiments using a tablet to obtain similarity measures between stimuli. On the tablet, the stimuli are displayed as icons that can be dragged with one finger to position them, depending on the ways they are perceived. By recording the x,y coordinates of the stimuli while subjects move the icons, the obtained data can reveal the cognitive processes of the subjects during the experiment. Such data, named digit-tracking data, can be analyzed with the SensoMineR package. In this article, we describe how researchers can design an experiment, how subjects can perform the experiment, and how digit-tracking data can be statistically analyzed within the Holos environment. At the end of the article, a short exemplary experiment is presented.

Hazard detection in noise-related incidents - the role of driving experience with battery electric vehicles.

PubMed

Cocron, Peter; Bachl, Veronika; Früh, Laura; Koch, Iris; Krems, Josef F

2014-12-01

The low noise emission of battery electric vehicles (BEVs) has led to discussions about how to address potential safety issues for other road users. Legislative actions have already been undertaken to implement artificial sounds. In previous research, BEV drivers reported that due to low noise emission they paid particular attention to pedestrians and bicyclists. For the current research, we developed a hazard detection task to test whether drivers with BEV experience respond faster to incidents, which arise due to the low noise emission, than inexperienced drivers. The first study (N=65) revealed that BEV experience only played a minor role in drivers' response to hazards resulting from low BEV noise. The tendency to respond, reaction times and hazard evaluations were similar among experienced and inexperienced BEV drivers; only small trends in the assumed direction were observed. Still, both groups clearly differentiated between critical and non-critical scenarios and responded accordingly. In the second study (N=58), we investigated additionally if sensitization to low noise emission of BEVs had an effect on hazard perception in incidents where the noise difference is crucial. Again, participants in all groups differentiated between critical and non-critical scenarios. Even though trends in response rates and latencies occurred, experience and sensitization to low noise seemed to only play a minor role in detecting hazards due to low BEV noise. An additional global evaluation of BEV noise further suggests that even after a short test drive, the lack of noise is perceived more as a comfort feature than a safety threat. Copyright © 2014 Elsevier Ltd. All rights reserved.

Archeointensity estimates of a tenth-century kiln: first application of the Tsunakawa-Shaw paleointensity method to archeological relics

NASA Astrophysics Data System (ADS)

Kitahara, Yu; Yamamoto, Yuhji; Ohno, Masao; Kuwahara, Yoshihiro; Kameda, Shuichi; Hatakeyama, Tadahiro

2018-05-01

Paleomagnetic information reconstructed from archeological materials can be utilized to estimate the archeological age of excavated relics, in addition to revealing the geomagnetic secular variation and core dynamics. The direction and intensity of the Earth's magnetic field (archeodirection and archeointensity) can be ascertained using different methods, many of which have been proposed over the past decade. Among the new experimental techniques for archeointensity estimates is the Tsunakawa-Shaw method. This study demonstrates the validity of the Tsunakawa-Shaw method to reconstruct archeointensity from samples of baked clay from archeological relics. The validity of the approach was tested by comparison with the IZZI-Thellier method. The intensity values obtained coincided at the standard deviation (1 σ) level. A total of 8 specimens for the Tsunakawa-Shaw method and 16 specimens for the IZZI-Thellier method, from 8 baked clay blocks, collected from the surface of the kiln were used in these experiments. Among them, 8 specimens (for the Tsunakawa-Shaw method) and 3 specimens (for the IZZI-Thellier method) passed a set of strict selection criteria used in the final evaluation of validity. Additionally, we performed rock magnetic experiments, mineral analysis, and paleodirection measurement to evaluate the suitability of the baked clay samples for paleointensity experiments and hence confirmed that the sample properties were ideal for performing paleointensity experiments. It is notable that the newly estimated archaomagnetic intensity values are lower than those in previous studies that used other paleointensity methods for the tenth century in Japan. [Figure not available: see fulltext.

Right supramarginal gyrus is crucial to overcome emotional egocentricity bias in social judgments.

PubMed

Silani, Giorgia; Lamm, Claus; Ruff, Christian C; Singer, Tania

2013-09-25

Humans tend to use the self as a reference point to perceive the world and gain information about other people's mental states. However, applying such a self-referential projection mechanism in situations where it is inappropriate can result in egocentrically biased judgments. To assess egocentricity bias in the emotional domain (EEB), we developed a novel visuo-tactile paradigm assessing the degree to which empathic judgments are biased by one's own emotions if they are incongruent to those of the person we empathize with. A first behavioral experiment confirmed the existence of such EEB, and two independent fMRI experiments revealed that overcoming biased empathic judgments is associated with increased activation in the right supramarginal gyrus (rSMG), in a location distinct from activations in right temporoparietal junction reported in previous social cognition studies. Using temporary disruption of rSMG with repetitive transcranial magnetic stimulation resulted in a substantial increase of EEB, and so did reducing visuo-tactile stimulation time as shown in an additional behavioral experiment. Our findings provide converging evidence from multiple methods and experiments that rSMG is crucial for overcoming emotional egocentricity. Effective connectivity analyses suggest that this may be achieved by early perceptual regulation processes disambiguating proprioceptive first-person information (touch) from exteroceptive third-person information (vision) during incongruency between self- and other-related affective states. Our study extends previous models of social cognition. It shows that although shared neural networks may underlie emotional understanding in some situations, an additional mechanism subserved by rSMG is needed to avoid biased social judgments in other situations.

Implicit motivational impact of pictorial health warning on cigarette packs.

PubMed

Volchan, Eliane; David, Isabel A; Tavares, Gisella; Nascimento, Billy M; Oliveira, Jose M; Gleiser, Sonia; Szklo, Andre; Perez, Cristina; Cavalcante, Tania; Pereira, Mirtes G; Oliveira, Leticia

2013-01-01

The use of pictorial warning labels on cigarette packages is one of the provisions included in the first ever global health treaty by the World Health Organization against the tobacco epidemic. There is substantial evidence demonstrating the effectiveness of graphic health warning labels on intention to quit, thoughts about health risks and engaging in cessation behaviors. However, studies that address the implicit emotional drives evoked by such warnings are still underexplored. Here, we provide experimental data for the use of pictorial health warnings as a reliable strategy for tobacco control. Experiment 1 pre-tested nineteen prototypes of pictorial warnings to screen for their emotional impact. Participants (n = 338) were young adults balanced in gender, smoking status and education. Experiment 2 (n = 63) tested pictorial warnings (ten) that were stamped on packs. We employed an innovative set-up to investigate the impact of the warnings on the ordinary attitude of packs' manipulation, and quantified judgments of warnings' emotional strength and efficacy against smoking. Experiment 1 revealed that women judged the warning prototypes as more aversive than men, and smokers judged them more aversive than non-smokers. Participants with lower education judged the prototypes more aversive than participants with higher education. Experiment 2 showed that stamped warnings antagonized the appeal of the brands by imposing a cost to manipulate the cigarette packs, especially for smokers. Additionally, participants' judgments revealed that the more aversive a warning, the more it is perceived as effective against smoking. Health warning labels are one of the key components of the integrated approach to control the global tobacco epidemic. The evidence presented in this study adds to the understanding of how implicit responses to pictorial warnings may contribute to behavioral change.

Anodal transcranial direct current stimulation of the right anterior temporal lobe did not significantly affect verbal insight.

PubMed

Aihara, Takatsugu; Ogawa, Takeshi; Shimokawa, Takeaki; Yamashita, Okito

2017-01-01

Humans often utilize past experience to solve difficult problems. However, if past experience is insufficient to solve a problem, solvers may reach an impasse. Insight can be valuable for breaking an impasse, enabling the reinterpretation or re-representation of a problem. Previous studies using between-subjects designs have revealed a causal relationship between the anterior temporal lobes (ATLs) and non-verbal insight, by enhancing the right ATL while inhibiting the left ATL using transcranial direct current stimulation (tDCS). In addition, neuroimaging studies have reported a correlation between right ATL activity and verbal insight. Based on these findings, we hypothesized that the right ATL is causally related to both non-verbal and verbal insight. To test this hypothesis, we conducted an experiment with 66 subjects using a within-subjects design, which typically has greater statistical power than a between-subjects design. Subjects participated in tDCS experiments across 2 days, in which they solved both non-verbal and verbal insight problems under active or sham stimulation conditions. To dissociate the effects of right ATL stimulation from those of left ATL stimulation, we used two montage types; anodal tDCS of the right ATL together with cathodal tDCS of the left ATL (stimulating both ATLs) and anodal tDCS of the right ATL with cathodal tDCS of the left cheek (stimulating only the right ATL). The montage used was counterbalanced across subjects. Statistical analyses revealed that, regardless of the montage type, there were no significant differences between the active and sham conditions for either verbal or non-verbal insight, although the finding for non-verbal insight was inconclusive because of a lack of statistical power. These results failed to support previous findings suggesting that the right ATL is the central locus of insight.

Implicit Motivational Impact of Pictorial Health Warning on Cigarette Packs

PubMed Central

Volchan, Eliane; David, Isabel A.; Tavares, Gisella; Nascimento, Billy M.; Oliveira, Jose M.; Gleiser, Sonia; Szklo, Andre; Perez, Cristina; Cavalcante, Tania; Pereira, Mirtes G.; Oliveira, Leticia

2013-01-01

Objective The use of pictorial warning labels on cigarette packages is one of the provisions included in the first ever global health treaty by the World Health Organization against the tobacco epidemic. There is substantial evidence demonstrating the effectiveness of graphic health warning labels on intention to quit, thoughts about health risks and engaging in cessation behaviors. However, studies that address the implicit emotional drives evoked by such warnings are still underexplored. Here, we provide experimental data for the use of pictorial health warnings as a reliable strategy for tobacco control. Methods Experiment 1 pre-tested nineteen prototypes of pictorial warnings to screen for their emotional impact. Participants (n = 338) were young adults balanced in gender, smoking status and education. Experiment 2 (n = 63) tested pictorial warnings (ten) that were stamped on packs. We employed an innovative set-up to investigate the impact of the warnings on the ordinary attitude of packs’ manipulation, and quantified judgments of warnings’ emotional strength and efficacy against smoking. Findings Experiment 1 revealed that women judged the warning prototypes as more aversive than men, and smokers judged them more aversive than non-smokers. Participants with lower education judged the prototypes more aversive than participants with higher education. Experiment 2 showed that stamped warnings antagonized the appeal of the brands by imposing a cost to manipulate the cigarette packs, especially for smokers. Additionally, participants’ judgments revealed that the more aversive a warning, the more it is perceived as effective against smoking. Conclusions Health warning labels are one of the key components of the integrated approach to control the global tobacco epidemic. The evidence presented in this study adds to the understanding of how implicit responses to pictorial warnings may contribute to behavioral change. PMID:23977223

Perceptions and experiences of nurse preceptors regarding their training courses: a mixed method study.

PubMed

Chang, Chia-Chi; Lin, Li-Min; Chen, I-Hui; Kang, Chun-Mei; Chang, Wen-Yin

2015-01-01

Although the benefits of preceptor training programs on the performance of nurse preceptors have been reported, research related to nurse preceptors' perceptions of and experiences with preceptor training courses is relatively limited. To explore nurse preceptors' perceptions of preceptor training courses and obtain information on their experiences in working as preceptors. A mixed method design was conducted. Nurse preceptors who currently work at one of eight hospitals in northern Taiwan were recruited to participate in this study. A questionnaire survey and focus group interviews were conducted. A training course perception scale was developed and generated based on the current nurse preceptor training programs offered in eight hospitals. Focus group interviews were conducted to obtain additional information on nurse preceptors' experiences in working as preceptors. The survey data were analyzed using descriptive statistics. Interview data were transcribed and analyzed using a qualitative content analysis approach. The results from the surveys of 386 nurse preceptors revealed that most courses included in the current preceptor training programs did not fulfill the learning needs of nurse preceptors and were clinically impractical. The most necessary and clinically useful course was the communication skills course, whereas the least useful course was the adult learning theory and principles course. Three themes were identified as problems based on the three focus group interviews conducted with 36 nurse preceptors: inadequate training was received before nurses were appointed as nurse preceptors, the courses were more theoretical rather than practical, and the preceptors experienced stress from multiple sources. The results revealed that the current preceptor training courses are impractical; therefore, the content of preceptor training courses must be altered to fulfill nurse preceptors' training needs. Furthermore, problems identified through the focus group interviews reinforce the survey results. Copyright © 2014 Elsevier Ltd. All rights reserved.

Chemical transformations of complex mixtures relevant to atmospheric processes: Laboratory and ambient studies

NASA Astrophysics Data System (ADS)

Samy, Shahryar (Shar)

The study of atmospheric chemistry and chemical transformations, which are relevant to conditions in the ambient atmosphere require the investigation of complex mixtures. In the atmosphere, complex mixtures (e.g. diesel emissions) are continually evolving as a result of physical and chemical transformations. This dissertation examines the transformations of modern diesel emissions (DE) in a series of experiments conducted at the European Outdoor Simulation Chamber (EUPHORE) in Valencia, Spain. Experimental design challenges are addressed, and the development of a NOx removal technology (denuder) is described with results from the application of the newly developed NOx denuder in the most recent EUPHORE campaign (2006). In addition, the data from an ambient aerosol study that examines atmospheric transformation products is presented and discussed. Atmospheric transformations of DE and associated secondary organic aerosol (SOA) production, along with chemical characterization of polar organic compounds (POC) in the EUPHORE experiments, provides a valuable insight on the tranformations of modern DE in environmentally relevant atmospheres. The greatest SOA production occurred in DE with toluene addition experiments (>40%), followed by DE with HCHO (for OH radical generation) experiments. A small amount of SOA (3%) was observed for DE in dark with N2O5 (for NO3 radical production) experiments. Distinct POC formation in light versus dark experiments suggests the role of OH initiated reactions in these chamber atmospheres. A trend of increasing concentrations of dicarboxylic acids in light versus dark experiments was observed when evaluated on a compound group basis. The production of diacids (as a compound group) demonstrates a consistent indicator for photochemical transformation in relation to studies in the ambient atmosphere. The four toluene addition experiments in this study were performed at different [tol]o/[NOx]o ratios and displayed an average SOA %yield (in relation to toluene) of 5.3+/-1.6%, which is compared to past chamber studies that evaluated the impact of [tol]o/[NO x]o on SOA production in more simplified mixtures. Characterization of nitrated polycyclic aromatic hydrocarbons (NPAH, nitroarenes), which have been shown to be mutagenic and/or carcinogenic, was performed on time-intergrated samples from the EUPHORE experiments. NPAH concentrations indicated significant formation and/or degradation was taking place. An inter-experimental comparison showed that distinct gas (2-nitronaphthalene) and particle (2-nitrofluoranthene, 4-nitropyrene) phase NPAH production resulted in light versus dark experiments, and degradation most likely due to photolysis was observed for one of the most abundant NPAH (1-nitropyrene) in the ambient atmosphere. The evaluation of dark experiments in high and low NOx conditions, revealed a significantly higher concentration of gas phase NPAH (mostly due to 1-nitronaphthalene) in high NOx experiments. Electrophilic nitration on chamber surfaces or sampling media can not be ruled out as a possible mechanism for the elevated NPAH concentrations. Chapter 5 presents results from an aerosol sampling study at the Storm Peak Laboratory (SPL) (3210 MSL, 40.45° N, 106.74° W) in the winter of 2007. The unique geographical character of SPL allows for extended observations/sampling of the free tropospheric interface. Of 84 analytes included in the GC-MS method, over 50 individual water extractable POC were present at concentrations greater than 0.1 ngm-3. Diurnal averages over the sampling period revealed a higher total concentration of POC at night, 211 ngm-3 (105-265 ngm-3), versus day, 160 ngm-3 (137-205 ngm -3), which suggests a more aged nighttime aerosol character. During a snow event (Jan. 11-13, 2007), the concentrations of daytime dicarboxylic acids, which may be considered as atmospheric transformation products, were reduced. Lower actinic flux, reduced transport distance, and ice crystal scavenging may explain this variability. Further evaluation of compound ratios (e.g. diacids to monoacids/levoglucosan) and the sampling period dynamics was performed to delineate diurnal aerosol character.

The impact of intimate partner violence and additional traumatic events on trauma symptoms and PTSD in preschool-aged children.

PubMed

Graham-Bermann, Sandra A; Castor, Lana E; Miller, Laura E; Howell, Kathryn H

2012-08-01

Children exposed to intimate partner violence (IPV) are at increased risk for developing traumatic stress symptoms and posttraumatic stress disorder (PTSD). Unfortunately, children who witness IPV are often exposed to additional traumatic events. Previous research has indicated that approximately one third of children experience 2 or more direct victimizations each year, and that exposure to one type of victimization places children at risk for exposure to additional types of victimization. Yet little is known about the impact of these additional traumas on children's functioning. For a sample of 120 preschool children (age 4-6 years) exposed to IPV in the past 2 years, 38% were exposed to additional traumatic events, including sexual assaults by family members, physical assaults, serious accidents, and/or life-threatening illnesses. Those exposed to both IPV and additional traumatic events had higher rates of PTSD diagnoses, traumatic stress symptoms (d = 0.96), and internalizing (d = 0.86) and externalizing behavior (d = 0.47) problems, than those exposed to IPV alone. We also compared DSM-IV diagnostic criteria to proposed criteria for evaluating traumatic stress in preschool-aged children. Results revealed the importance of conducting a complete assessment of traumatic events prior to treating children exposed to IPV. Copyright © 2012 International Society for Traumatic Stress Studies.

Relation between contemplative exercises and an enriched psychology students' experience in a neuroscience course

PubMed Central

Levit Binnun, Nava; Tarrasch, Ricardo

2014-01-01

This article examines the relation of contemplative exercises with enhancement of students' experience during neuroscience studies. Short contemplative exercises inspired by the Buddhist tradition of self-inquiry were introduced in an undergraduate neuroscience course for psychology students. At the start of the class, all students were asked to participate in short “personal brain investigations” relevant to the topic presented. These investigations were aimed at bringing stable awareness to a specific perceptual, emotional, attentional, or cognitive process and observing it in a non-judgmental, non-personal way. In addition, students could choose to participate, for bonus credit, in a longer exercise designed to expand upon the weekly class activity. In the exercise, students continued their “personal brain investigations” for 10 min a day, 4 days a week. They wrote “lab reports” on their daily observations, obtained feedback from the teacher, and at the end of the year reviewed their reports and reflected upon their experiences during the semester. Out of 265 students, 102 students completed the bonus track and their final reflections were analyzed using qualitative methodology. In addition, 91 of the students answered a survey at the end of the course, 43 students participated in a quiz 1 year after course graduation, and the final grades of all students were collected and analyzed. Overall, students reported satisfaction from the exercises and felt they contributed to their learning experience. In the 1-year follow-up, the bonus-track students were significantly more likely than their peers to remember class material. The qualitative analysis of bonus-track students' reports revealed that the bonus-track process elicited positive feelings, helped students connect with class material and provided them with personal insights. In addition, students acquired contemplative skills, such as increased awareness and attention, non-judgmental attitudes, and better stress-management abilities. We provide examples of “personal brain investigations” and discuss limitations of introducing a contemplative approach. PMID:25477833

Expression of multidrug resistance efflux pump gene norA is iron responsive in Staphylococcus aureus.

PubMed

Deng, Xin; Sun, Fei; Ji, Quanjiang; Liang, Haihua; Missiakas, Dominique; Lan, Lefu; He, Chuan

2012-04-01

Staphylococcus aureus utilizes efflux transporter NorA to pump out a wide range of structurally dissimilar drugs, conferring low-level multidrug resistance. The regulation of norA expression has yet to be fully understood although past studies have revealed that this gene is under the control of the global transcriptional regulator MgrA and the two-component system ArlRS. To identify additional regulators of norA, we screened a transposon library in strain Newman expressing the transcriptional fusion norA-lacZ for altered β-galactosidase activity. We identify a transposon insertion in fhuB, a gene that encodes a ferric hydroxamate uptake system permease, and propose that the norA transcription is iron responsive. In agreement with this observation, addition of FeCl(3) repressed the induction of norA-lacZ, suggesting that bacterial iron uptake plays an important role in regulating norA transcription. In addition, a fur (ferric uptake regulator) deletion exhibited compromised norA transcription and reduced resistance to quinolone compared to the wild-type strain, indicating that fur functions as a positive regulator of norA. A putative Fur box identified in the promoter region of norA was confirmed by electrophoretic mobility shift and DNase I footprint assays. Finally, by employing a siderophore secretion assay, we reveal that NorA may contribute to the export of siderophores. Collectively, our experiments uncover some novel interactions between cellular iron level and norA regulation in S. aureus.

Expression of Multidrug Resistance Efflux Pump Gene norA Is Iron Responsive in Staphylococcus aureus

PubMed Central

Deng, Xin; Sun, Fei; Ji, Quanjiang; Liang, Haihua; Missiakas, Dominique; Lan, Lefu

2012-01-01

Staphylococcus aureus utilizes efflux transporter NorA to pump out a wide range of structurally dissimilar drugs, conferring low-level multidrug resistance. The regulation of norA expression has yet to be fully understood although past studies have revealed that this gene is under the control of the global transcriptional regulator MgrA and the two-component system ArlRS. To identify additional regulators of norA, we screened a transposon library in strain Newman expressing the transcriptional fusion norA-lacZ for altered β-galactosidase activity. We identify a transposon insertion in fhuB, a gene that encodes a ferric hydroxamate uptake system permease, and propose that the norA transcription is iron responsive. In agreement with this observation, addition of FeCl3 repressed the induction of norA-lacZ, suggesting that bacterial iron uptake plays an important role in regulating norA transcription. In addition, a fur (ferric uptake regulator) deletion exhibited compromised norA transcription and reduced resistance to quinolone compared to the wild-type strain, indicating that fur functions as a positive regulator of norA. A putative Fur box identified in the promoter region of norA was confirmed by electrophoretic mobility shift and DNase I footprint assays. Finally, by employing a siderophore secretion assay, we reveal that NorA may contribute to the export of siderophores. Collectively, our experiments uncover some novel interactions between cellular iron level and norA regulation in S. aureus. PMID:22267518

Motion in action: A study of second graders' trajectories of experience during guided inquiry science instruction

NASA Astrophysics Data System (ADS)

Hapgood, Susanna Elizabeth

This interpretive case study describes a 10-day inquiry science program of study of motion down inclined planes during which a class of 21 second graders investigated scientific relationships such as mass and speed, speed and momentum, and mass and momentum via both text-based experiences ("second-hand investigations") and hands-on materials-based experiments ("first-hand investigations"). Data sources included over 11 hours of videotaped instruction in addition to children's written work, class-generated artifacts, and paper-and-pencil pre- and posttests. Content analyses informed by both sociocultural and developmental perspectives revealed that, in addition to a significant increase in pre- to posttest scores, children in the class engaged in several processes integral to inquiry, namely, (a) using data as evidence, (b) evaluating investigative procedures, and (c) making sense of multiple forms of representations. In addition, the study describes the range of and shifts in children's ideas about scientific relationships fundamental to developing an understanding of motion. Many children were observed to make causal attributions involving a relationship between two variables, such as the mass and momentum of a ball rolling down a ramp. Discussed are mediating factors such as the teacher's role in scaffolding the class's investigations and features of the innovative "scientists' notebook" texts, which were integral to the instruction. Also presented is evidence of first-hand and second-hand investigations working in concert to provide the elementary school students with rich opportunities to learn and to express their developing understandings of scientific ideas. This study provides a rare glimpse of primary-grade inquiry-based science instruction within a classroom context.

The Dynamic Reactance Interaction - How Vested Interests Affect People's Experience, Behavior, and Cognition in Social Interactions.

PubMed

Steindl, Christina; Jonas, Eva

2015-01-01

In social interactions, individuals may sometimes pursue their own interests at the expense of their interaction partner. Such self-interested behaviors impose a threat to the interaction partner's freedom to act. The current article investigates this threat in the context of interdependence and reactance theory. We explore how vested interests influence reactance process stages of an advisor-client interaction. We aim to explore the interactional process that evolves. In two studies, participants took the perspective of a doctor (advisor) or a patient (client). In both studies we incorporated a vested interest. In Study 1 (N = 82) we found that in response to a vested interest of their interaction partner, patients indicated a stronger experience of reactance, more aggressive behavioral intentions, and more biased cognitions than doctors. A serial multiple mediation revealed that a vested interest engendered mistrust toward the interaction partner and this mistrust led to an emerging reactance process. Study 2 (N = 207) further demonstrated that doctors expressed their reactance in a subtle way: they revealed a classic confirmation bias when searching for additional information on their preliminary decision preference, indicating stronger defense motivation. We discuss how these findings can help us to understand how social interactions develop dynamically.

The Dynamic Reactance Interaction – How Vested Interests Affect People’s Experience, Behavior, and Cognition in Social Interactions

PubMed Central

Steindl, Christina; Jonas, Eva

2015-01-01

In social interactions, individuals may sometimes pursue their own interests at the expense of their interaction partner. Such self-interested behaviors impose a threat to the interaction partner’s freedom to act. The current article investigates this threat in the context of interdependence and reactance theory. We explore how vested interests influence reactance process stages of an advisor–client interaction. We aim to explore the interactional process that evolves. In two studies, participants took the perspective of a doctor (advisor) or a patient (client). In both studies we incorporated a vested interest. In Study 1 (N = 82) we found that in response to a vested interest of their interaction partner, patients indicated a stronger experience of reactance, more aggressive behavioral intentions, and more biased cognitions than doctors. A serial multiple mediation revealed that a vested interest engendered mistrust toward the interaction partner and this mistrust led to an emerging reactance process. Study 2 (N = 207) further demonstrated that doctors expressed their reactance in a subtle way: they revealed a classic confirmation bias when searching for additional information on their preliminary decision preference, indicating stronger defense motivation. We discuss how these findings can help us to understand how social interactions develop dynamically. PMID:26640444

Sexual reproduction as the cause of heat resistance in the food spoilage fungus Byssochlamys spectabilis (anamorph Paecilomyces variotii).

PubMed

Houbraken, Jos; Varga, János; Rico-Munoz, Emilia; Johnson, Shawn; Samson, Robert A

2008-03-01

Paecilomyces variotii is a common cosmopolitan species that is able to spoil various food- and feedstuffs and is frequently encountered in heat-treated products. However, isolates from heat-treated products rarely form ascospores. In this study we examined by using molecular techniques and mating tests whether this species can undergo a sexual cycle and form ascospores. The population structure of this species was examined by analyzing the nuclear ribosomal internal transcribed spacer 1 (ITS1) and ITS2 and the 5.8S rRNA gene, as well as partial beta-tubulin, actin, and calmodulin gene sequences. Phylogenetic analyses revealed that P. variotii is a highly variable species. Partition homogeneity tests revealed that P. variotii has a recombining population structure. In addition to sequence analyses, mating experiments indicated that P. variotii is able to form ascomata and ascospores in culture in a heterothallic manner. The distribution of MAT1-1 and MAT1-2 genes showed a 1:1 ratio in the progeny of the mating experiments. From the sequence analyses and mating data we conclude that P. variotii is the anamorph of Talaromyces spectabilis and that it has a biallelic heterothallic mating system. Since Paecilomyces sensu stricto anamorphs group within Byssochlamys, a new combination Byssochlamys spectabilis is proposed.

Literature as an exploration of the phenomenology of schizophrenia: disorder and recovery in Denis Johnson's Jesus' Son.

PubMed

Hamm, Jay A; Leonhardt, Bethany L; Fogley, Rebecca L; Lysaker, Paul H

2014-12-01

When read as a fictional psychosis narrative, Jesus' Son, a collection of short stories by Denis Johnson, reveals important elements of the phenomenology of schizophrenia and recovery. It is possible that Jesus' Son, as a work of fiction, may be able to uniquely add depth and nuance to an understanding of the phenomenology of schizophrenia involving a state of psychological fragmentation, an ever-changing interpersonal field and a loss of personal agency. In addition, by following the protagonist in Jesus' Son as he begins to resolve some of his difficulties, the book also offers an individualised account of recovery. The authors detail how the book reveals these insights about schizophrenia and recovery and suggest that these elements are intertwined in such a manner that leads to a profound disruption of self-experience, characterised by a collapse of metacognitive processes. Jesus' Son may add depth to our understanding of the subjective experience of schizophrenia and recovery, and also may serve as one example in which the study of humanities offers an opportunity to explore the human elements in the most profound forms of suffering. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Proton Energy Optimization and Spatial Distribution Analysis from a Thickness Study Using Liquid Crystal Targets

NASA Astrophysics Data System (ADS)

Willis, Christopher; Poole, Patrick; Schumacher, Douglas; Freeman, Richard; van Woerkom, Linn

2016-10-01

Laser-accelerated ions from thin targets have been widely studied for applications including secondary radiation sources and cancer therapy, with recent studies trending towards thinner targets which can provide improved ion energies and yields. Here we discuss results from an experiment on the Scarlet laser at OSU using variable thickness liquid crystal targets. On this experiment, the spatial and spectral distributions of accelerated ions were measured along target normal and laser axes at varying thicknesses from 150nm to 2000nm at a laser intensity of 1 ×1020W /cm2 . Maximum ion energy was observed for targets in the 600 - 800nm thickness range, with proton energies reaching 24MeV . The ions were further characterized using radiochromic film, revealing an unusual spatial distribution on many laser shots. Here, the peak ion yield falls in an annular ring surrounding the target normal, with an increasing divergence angle as a function of ion energy. Details of these spatial and spectral ion distributions will be presented, including spectral deconvolution of the RCF data, revealing additional trends in the accelerated ion distributions. Supported by the DARPA PULSE program through a Grant from AMRDEC, and by the NNSA under contract DE-NA0001976.

Irradiation experiment on ZrC-coated fuel particles for high-temperature gas-cooled reactors

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

Minato, Kazuo; Ogawa, Toru; Sawa, Kazuhiro

2000-06-01

The ZrC coating layer is a candidate to replace the SiC coating layer of the Triso-coated fuel particle. To compare the irradiation performance of the ZrC Triso-coated fuel particles with that of the normal Triso-coated fuel particles at high temperatures, a capsule irradiation experiment was performed, where both types of the coated fuel particles were irradiated under identical conditions. The burnup was 4.5% FIMA and the irradiation temperature was 1,400 to 1,650 C. The postirradiation measurement of the through-coating failure fractions of both types of coated fuel particles revealed better irradiation performance of the ZrC Triso-coated fuel particles. The opticalmore » microscopy and electron probe microanalysis on the polished cross section of the ZrC Triso-coated fuel particles revealed no interaction of palladium with the ZrC coating layer nor accumulation of palladium at the inner surface of the ZrC coating layer, whereas severe corrosion of the SiC coating layer was observed in the normal Triso-coated fuel particles. Although no corrosion of the ZrC coating layer was observed, additional evaluations need to be made of this layer's ability to satisfactorily retain the fission product palladium.« less

Association of p60c-src with endosomal membranes in mammalian fibroblasts

PubMed Central

1992-01-01

We have examined the subcellular localization of p60c-src in mammalian fibroblasts. Analysis of indirect immunofluorescence by three- dimensional optical sectioning microscopy revealed a granular cytoplasmic staining that co-localized with the microtubule organizing center. Immunofluorescence experiments with antibodies against a number of membrane markers demonstrated a striking co-localization between p60c-src and the cation-dependent mannose-6-phosphate receptor (CI- MPR), a marker that identifies endosomes. Both p60c-src and the CI-MPR were found to cluster at the spindle poles throughout mitosis. In addition, treatment of interphase and mitotic cells with brefeldin A resulted in a clustering of p60c-src and CI-MPR at a peri-centriolar position. Biochemical fractionation of cellular membranes showed that a major proportion of p60c-src co-enriched with endocytic membranes. Treatment of membranes containing HRP to alter their apparent density also altered the density of p60c-src-containing membranes. Similar density shift experiments with total cellular membranes revealed that the majority of membrane-associated p60c-src in the cell is associated with endosomes, while very little is associated with plasma membranes. These results support a role for p60c-src in the regulation of endosomal membranes and protein trafficking. PMID:1378446

A field reciprocal transplant experiment reveals asymmetric costs of migration between lake and river ecotypes of three-spined sticklebacks (Gasterosteus aculeatus).

PubMed

Kaufmann, J; Lenz, T L; Kalbe, M; Milinski, M; Eizaguirre, C

2017-05-01

Theory of local adaptation predicts that nonadapted migrants will suffer increased costs compared to local residents. Ultimately this process can result in the reduction of gene flow and culminate in speciation. Here, we experimentally investigated the relative fitness of migrants in foreign habitats, focusing on diverging lake and river ecotypes of three-spined sticklebacks. A reciprocal transplant experiment performed in the field revealed asymmetric costs of migration: whereas mortality of river fish was increased under lake conditions, lake migrants suffered from reduced growth relative to river residents. Selection against migrants thus involved different traits in each habitat but generally contributed to bidirectional reduction in gene flow. Focusing particularly on the parasitic environments, migrant fish differed from resident fish in the parasite community they harboured. This pattern correlated with both cellular phenotypes of innate immunity as well as with allelic variation at the genes of the major histocompatibility complex. In addition to showing the costs of migration in three-spined sticklebacks, this study highlights the role of asymmetric selection particularly from parasitism in genotype sorting and in the emergence of local adaptation. © 2017 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2017 European Society For Evolutionary Biology.

All in the family: Work-family enrichment and crossover among farm couples.

PubMed

Sprung, Justin M; Jex, Steve M

2017-04-01

This study expands upon the contextualization of the work-family interface by examining positive work-family experiences within the farming industry. Both individual and crossover effects were examined among a sample of 217 married farm couples. Results demonstrated multiple significant relationships between self-reported attitudes, work-family enrichment, and health outcomes. In addition, crossover effects reveal the importance of individual attitudes (husband work engagement and wife farm satisfaction) for spousal work-family enrichment and health outcomes. Furthermore, individual work-family enrichment was positively related to spousal psychological health and negatively related to spousal physical symptoms. Many of these findings remained significant after controlling for work-family conflict. Overall, our results suggest the potential beneficial impact of the integrated work-family dynamic associated with the farming profession for positive work-family experiences. Implications of these findings, as well as directions for future research, are discussed. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Energy analysis of convectively induced wind perturbations

NASA Technical Reports Server (NTRS)

Fuelberg, Henry E.; Buechler, Dennis E.

1989-01-01

Budgets of divergent and rotational components of kinetic energy (KD and KR) are examined for four upper level wind speed maxima that develop during the fourth Atmospheric Variability Experiment (AVE IV) and the first AVE-Severe Environmental Storms and Mesoscale Experiment (AVE-SESAME I). A similar budget analysis is performed for a low-level jet stream during AVE-SESAME I. The energetics of the four upper level speed maxima is found to have several similarities. The dominant source of KD is cross-contour flow by the divergent wind, and KD provides a major source of KR via a conversion process. Conversion from available potential energy provides an additional source of KR in three of the cases. Horizontal maps reveal that the conversions involving KD are maximized in regions poleward of the convection. Low-level jet development during AVE-SESAME I appears to be assisted by convective activity to the west.

Highly Superior Autobiographical Memory: Quality and Quantity of Retention Over Time

PubMed Central

LePort, Aurora K. R.; Stark, Shauna M.; McGaugh, James L.; Stark, Craig E. L.

2016-01-01

Individuals who have Highly Superior Autobiographical Memory (HSAM) are able to recall, with considerable accuracy, details of daily experiences that occurred over many previous decades. The present study parametrically investigates the quantity and quality of details of autobiographical memories acquired 1-week, 1-month, 1-year, and 10-years prior in HSAMs and controls. In addition, we tested the consistency of details provided at the 1-week delay by testing the subjects 1 month later with a surprise assessment. At the 1-week delay, HSAMs and controls recalled an equivalent number of events. In contrast, HSAM recall performance was superior at more remote delays, with remarkable consistency following a 1-month delay. Further, we revealed a relationship between the consistency of recall and HSAMs’ obsessive–compulsive tendencies. These data suggest that HSAMs experience normal encoding, yet enhanced consolidation and later recall of autobiographical events. PMID:26834661

Inter-laboratory comparison of the in vivo comet assay including three image analysis systems.

PubMed

Plappert-Helbig, Ulla; Guérard, Melanie

2015-12-01

To compare the extent of potential inter-laboratory variability and the influence of different comet image analysis systems, in vivo comet experiments were conducted using the genotoxicants ethyl methanesulfonate and methyl methanesulfonate. Tissue samples from the same animals were processed and analyzed-including independent slide evaluation by image analysis-in two laboratories with extensive experience in performing the comet assay. The analysis revealed low inter-laboratory experimental variability. Neither the use of different image analysis systems, nor the staining procedure of DNA (propidium iodide vs. SYBR® Gold), considerably impacted the results or sensitivity of the assay. In addition, relatively high stability of the staining intensity of propidium iodide-stained slides was found in slides that were refrigerated for over 3 months. In conclusion, following a thoroughly defined protocol and standardized routine procedures ensures that the comet assay is robust and generates comparable results between different laboratories. © 2015 Wiley Periodicals, Inc.

The full metallic double-pigtail ureteral stent: Review of the clinical outcome and current status

PubMed Central

Kallidonis, Panagiotis S.; Georgiopoulos, Ioannis S.; Kyriazis, Iason D.; Kontogiannis, Stavros; Al-Aown, Abdulrahman M.; Liatsikos, Evangelos N.

2015-01-01

The full metallic double-J ureteral stent (MS) was introduced as a method for providing long-term drainage in malignant ureteral obstruction. Experimental evaluation of the MS revealed that its mechanical features allow efficient drainage in difficult cases, which could not be managed by the insertion of a standard polymeric double-J stent. Clinical experience with the MS showed controversial results. Careful patient selection results in efficient long-term management of malignant ureteral obstruction. The use of the MS should also be considered in selected benign cases. Major complications are uncommon and the minor complications should not hinder its use. Experience in pediatric patients is limited and warrants additional study. The cost-effectiveness of the MS seems to be appropriate for long-term treatment. Further investigation with comparative clinical trials would document the outcome more extensively and establish the indications as well as the selection criteria for the MS. PMID:25624569

Validity of false belief tasks in blind children.

PubMed

Brambring, Michael; Asbrock, Doreen

2010-12-01

Previous studies have reported that congenitally blind children without any additional impairment reveal a developmental delay of at least 4 years in perspective taking based on testing first-order false-belief tasks. These authors interpret this delay as a sign of autism-like behavior. However, the delay may be caused by testing blind children with false-belief tasks that require visual experience. Therefore, the present study gave alternative false-belief tasks based on tactile or auditory experience to 45 congenitally blind 4-10-year-olds and 37 sighted 3-6-year-olds. Results showed criterion performance at 80 months (6; 8 years) in blind children compared with 61 months (5; 1 years) in sighted controls. It is concluded that this 19-month (1; 7 year) difference, which is comparable with delays in other developmental areas, is a developmental delay caused by the fact of congenital blindness rather than a sign of a psychopathological disorder of autism-like behavior.

Experiences of college-age youths in families with a recessive genetic condition.

PubMed

Hern, Marcia J; Beery, Theresa A; Barry, Detrice G

2006-05-01

Growing up in a family with a recessive genetic condition can trigger questions about progeny effect. This study explored perceptions of family hardiness and information sharing by 18- to 21-year-olds about genetic risk. Semistructured interviews, the Family Hardiness Index (FHI), and a Family Information Sharing Analog Scale (FISAS) were used. Participants included 11 youths who had relatives with hemophilia and 4 with sickle cell anemia. Findings revealed seven themes: assimilating premature knowledge; caring for others, denying self; cautioning during development; experiencing continual sickness; feeling less than; magnifying transition experiences; and sustaining by faith. There was no significant correlation between total FHI and FISAS. However, there was a statistically significant difference in FISAS between genetic condition variance. Specifically, higher hardiness was found and information sharing correlated among college youths in families with hemophilia. Additional research can lead to nursing interventions to provide genetic information to youths in families for illness variance.

Integration of Video-Based Demonstrations to Prepare Students for the Organic Chemistry Laboratory

NASA Astrophysics Data System (ADS)

Nadelson, Louis S.; Scaggs, Jonathan; Sheffield, Colin; McDougal, Owen M.

2015-08-01

Consistent, high-quality introductions to organic chemistry laboratory techniques effectively and efficiently support student learning in the organic chemistry laboratory. In this work, we developed and deployed a series of instructional videos to communicate core laboratory techniques and concepts. Using a quasi-experimental design, we tested the videos in five traditional laboratory experiments by integrating them with the standard pre-laboratory student preparation presentations and instructor demonstrations. We assessed the influence of the videos on student laboratory knowledge and performance, using sections of students who did not view the videos as the control. Our analysis of pre-quizzes revealed the control group had equivalent scores to the treatment group, while the post-quiz results show consistently greater learning gains for the treatment group. Additionally, the students who watched the videos as part of their pre-laboratory instruction completed their experiments in less time.

Psychological homelessness and enculturative stress among US-deported Salvadorans: a preliminary study with a novel approach.

PubMed

Negy, Charles; Reig-Ferrer, Abilio; Gaborit, Mauricio; Ferguson, Christopher J

2014-12-01

The purpose of this study was to examine the construct psychological homelessness-feelings of not belonging in one's home country-within the context of deported Salvadorans' enculturation to El Salvador. Participants (n = 66) who had been deported from the United States completed a set of questionnaires related to their deportation experience. Results indicated that deportees, in various degrees, experienced the phenomenon of psychological homelessness and enculturative stress related to living in El Salvador. As hypothesized, enculturative stress related to re-adapting to life in El Salvador significantly correlated with psychological homelessness after controlling for time spent in the United States, acculturation, and enculturation. Additional analyses revealed that maladaptive cognitions related to the deportation experience also predicted psychological homelessness. Our findings suggest psychological homelessness appears to be a valid construct and is experienced by many undocumented immigrants.

Linking Narcissism, Motivation, and Doping Attitudes in Sport: A Multilevel Investigation Involving Coaches and Athletes.

PubMed

Matosic, Doris; Ntoumanis, Nikos; Boardley, Ian David; Stenling, Andreas; Sedikides, Constantine

2016-12-01

Research on coaching (Bartholomew, Ntoumanis, & Thøgersen-Ntoumani, 2009) has shown that coaches can display controlling behaviors that have detrimental effects on athletes' basic psychological needs and quality of sport experiences. The current study extends this literature by considering coach narcissism as a potential antecedent of coaches' controlling behaviors. Further, the study tests a model linking coaches' (n = 59) own reports of narcissistic tendencies with athletes' (n = 493) perceptions of coach controlling behaviors, experiences of need frustration, and attitudes toward doping. Multilevel path analysis revealed that coach narcissism was directly and positively associated with athletes' perceptions of controlling behaviors and was indirectly and positively associated with athletes' reports of needs frustration. In addition, athletes' perceptions of coach behaviors were positively associated-directly and indirectly-with attitudes toward doping. The findings advance understanding of controlling coach behaviors, their potential antecedents, and their associations with athletes' attitudes toward doping.

Growth and substrate consumption of Nitrobacter agilis cells immobilized in carrageenan: part 1. Dynamic modeling.

PubMed

de Gooijer, C D; Wijffels, R H; Tramper, J

1991-07-01

The modeling of the growth of Nitrobacter agilis cell immobilized in kappa-carrageenan is presented. A detailed description is given of the modeling of internal diffusion and growth of cells in the support matrix in addition to external mass transfer resistance. The model predicts the substrate and biomass profiles in the support as well as the macroscopic oxygen consumption rate of the immobilized biocatalyst in time. The model is tested by experiments with continuously operated airlift loop reactors containing cells immobilized in kappa-carrageenan. The model describes experimental data very well. It is clearly shown that external mass transfer may not be neglected. Furthermore, a sensitivity analysis of the parameters at their values during the experiments revealed that apart from the radius of the spheres and the substrate bulk concentration, the external mass transfer resistance coefficient is the most sensitive parameter for our case.

Thermoacoustic chips with carbon nanotube thin yarn arrays.

PubMed

Wei, Yang; Lin, Xiaoyang; Jiang, Kaili; Liu, Peng; Li, Qunqing; Fan, Shoushan

2013-10-09

Aligned carbon nanotube (CNT) films drawn from CNT arrays have shown the potential as thermoacoustic loudspeakers. CNT thermoacoustic chips with robust structures are proposed to promote the applications. The silicon-based chips can play sound and fascinating rhythms by feeding alternating currents and audio signal to the suspending CNT thin yarn arrays across grooves in them. In additional to the thin yarns, experiments further revealed more essential elements of the chips, the groove depth and the interdigital electrodes. The sound pressure depends on the depth of the grooves, and the thermal wavelength can be introduced to define the influence-free depth. The interdigital fingers can effectively reduce the driving voltage, making the chips safe and easy to use. The chips were successfully assembled into earphones and have been working stably for about one year. The thermoacoustic chips can find many applications in consumer electronics and possibly improve the audiovisual experience.

Fretting of titanium at temperatures to 650 C in air

NASA Technical Reports Server (NTRS)

Bill, R. C.

1975-01-01

Fretting wear experiments were conducted on high-purity titanium at temperatures up to 650 C. Results indicate that up to about 500 C, the fretting wear increases with temperature. A further increase in the temperature up to 650 C results in decreasing fretting wear. This change in trend of fretting wear with temperature is shown to be associated with a change in oxidation rate. Additional experiments at 650 C showed a transmission from a low rate of fretting wear to a higher rate occurred after exposure to a number of fretting cycles; the number of cycles required to cause this transition was dependent on the normal load. Scanning electron microscopy studies revealed that this transition was marked by cracking and disruption of the surface oxide film. A model was proposed that coupled the oxidation rate kinetics of titanium at 650 C with the occurrence of wear at the surface of the oxide film.

Profilin as a regulator of the membrane-actin cytoskeleton interface in plant cells

PubMed Central

Sun, Tiantian; Li, Shanwei; Ren, Haiyun

2013-01-01

Membrane structures and cytoskeleton dynamics are intimately inter-connected in the eukaryotic cell. Recently, the molecular mechanisms operating at this interface have been progressively addressed. Many experiments have revealed that the actin cytoskeleton can interact with membranes through various discrete membrane domains. The actin-binding protein, profilin has been proven to inhibit actin polymerization and to promote F-actin elongation. This is dependent on many factors, such as the profilin/G-actin ratio and the ionic environment of the cell. Additionally, profilin has specific domains that interact with phosphoinositides and poly-L-proline rich proteins; theoretically, this gives profilin the opportunity to interact with membranes, and a large number of experiments have confirmed this possibility. In this article, we summarize recent findings in plant cells, and discuss the evidence of the connections among actin cytoskeleton, profilin and biomembranes through direct or indirect relationships. PMID:24391654

The investigation of soot and temperature distributions in a visualized direct injection diesel engine using laser diagnostics

NASA Astrophysics Data System (ADS)

Han, Yong-taek; Kim, Ki-bum; Lee, Ki-hyung

2008-11-01

Based upon the method of temperature calibration using the diffusion flame, the temperature and soot concentrations of the turbulent flame in a visualized diesel engine were qualitatively measured. Two different cylinder heads were used to investigate the effect of swirl ratio within the combustion chamber. From this experiment, we find that the highest flame temperature of the non-swirl head engine is approximately 2400 K and that of the swirl head engine is 2100 K. In addition, as the pressure of fuel injection increases, the in-cylinder temperature increases due to the improved combustion of a diesel engine. This experiment represented the soot quantity in the KL factor and revealed that the KL factor was high when the fuel collided with the cylinder wall. Moreover, the KL factor was also high in the area of the chamber where the temperature dropped rapidly.

Teacher's perception of primary schoolchildren's undesirable behaviors: the effect of teaching experience, pupil's age, sex and ability stream.

PubMed

Borg, M G; Falzon, J M

1990-06-01

Using a self-administered questionnaire, the attitudes of 844 Maltese primary school teachers towards 16 selected undesirable behaviours were surveyed. Results indicated that pupils' age is a significant moderator of half of the behaviours; these are perceived to be significantly more serious by teachers in the second three years of the primary school than by their colleagues in the first three years. Significant boy-girl differences in the seriousness of behaviour were revealed in most of the behaviours as rated by teachers in both the first and in the second years. In addition, length of teaching experience was found to be a significant moderator of the perceived seriousness of some of the behaviours: the less experienced, when compared with the more experienced, judged these behaviours as being more serious. Ability stream did not have any significant effects on the teachers' attitudes towards the undesirable behaviours.

Microstructural Constraints on the Formation History of Hibonite in Refractory Inclusions

NASA Technical Reports Server (NTRS)

Han, J.; Koop, L.; Keller, L. P.; Davis, A. M.

2017-01-01

Hibonite is a primary refractory phase occurring in many Ca-Al-rich inclusions (CAIs), typically with spinel and perovskite [1]. Previous mi-crostructural studies of hibonite in CAIs revealed the presence of numerous stacking defects along the (001) plane and correlated non-stoichiometry in hibonite [2,3]. These features are interpreted as complex inter-growths of stoichiometric and Ca-deficient hibonites, as shown by experimental studies of reaction-sintered CaO-Al2O3 compounds [4]. Here, we extend our transmission electron microscope (TEM) studies to hibonite-bearing CAIs in CM chondrites that have been well characterized isotopically [5-7]. In addition, we have undertaken a series of anneal-ing experiments to explore the effect of minor elements (Mg and Ti) on the microstucure of hibonite [8,9,this study]. The results of these experiments are being applied to hibonite in CAIs in order to better understand its formation conditions.

Spatial ability in secondary school students: intra-sex differences based on self-selection for physical education.

PubMed

Tlauka, Michael; Williams, Jennifer; Williamson, Paul

2008-08-01

Past research has demonstrated consistent sex differences with men typically outperforming women on tests of spatial ability. However, less is known about intra-sex effects. In the present study, two groups of female students (physical education and non-physical education secondary students) and two corresponding groups of male students explored a large-scale virtual shopping centre. In a battery of tasks, spatial knowledge of the shopping centre as well as mental rotation ability were tested. Additional variables considered were circulating testosterone levels, the ratio of 2D:4D digit length, and computer experience. The results revealed both sex and intra-sex differences in spatial ability. Variables related to virtual navigation and computer ability and experience were found to be the most powerful predictors of group membership. Our results suggest that in female and male secondary students, participation in physical education and spatial skill are related.

Ultrasonic synthesis of In-doped SnS nanoparticles and their physical properties

NASA Astrophysics Data System (ADS)

Jamali-Sheini, Farid; Cheraghizade, Mohsen; Yousefi, Ramin

2018-05-01

Indium (In)-doped Tin (II) Sulfide (SnS) nanoparticles (NPs) were synthesized by an ultra-sonication method and their optical, electrical, dielectric and photocatalytic properties were investigated. XRD patterns of the obtained NPs indicated formation of orthorhombic polycrystalline SnS. Field emission scanning electron microscopy exhibited flower-like NPs with particle sizes below 100 nm for both SnS and In-doped SnS samples. Optical analysis showed a decrease in energy band gap of SnS NPs upon In doping. In addition, electrical results demonstrated p-type nature of the synthesized SnS NPs and enhanced electrical conductivity of the NPs due to increased tin vacancy. Dielectric experiments on SnS NPs suggested an electronic polarizations effect to be responsible for changing dielectric properties of the particles, in terms of frequency. Finally, photocatalytic experiments revealed that high degradation power can be obtained using In-doped SnS NPs.

An etiological study of phthalate self-contamination of spacecraft and contamination from their earthly environs

NASA Technical Reports Server (NTRS)

Gross, F. C.; Colony, J. A.

1972-01-01

Phthalates are very objectionable contaminants in space experiments because of their strong absorption in the UV and IR regions of the spectrum. Thus, even minute amounts of these compounds migrating to optical equipment, in test or space flight conditions, can seriously compromise the results of experiments by altering the sensitivity of the functional equipment. Volatility data of the phthalates and other plasticizers are presented in addition to UV spectra of ultrathin films of these same types of compounds. Sources of plasticizer contamination are revealed with special recognition given to di-2-ethylhexyl phthalate (DEHP), the single most ubiquitous plasticizer in use. A surprisingly large percentage of the outgassing condensates from vacuum testing of spacecraft contain DEHP as well as other plasticizers. IR and gas chromatography/mass spectroscopy methods were used to analyze samples from spacecraft. Methods for successful reduction of plasticizers and other contaminants are mentioned.

New mechanistically based model for predicting reduction of biosolids waste by ozonation of return activated sludge.

PubMed

Isazadeh, Siavash; Feng, Min; Urbina Rivas, Luis Enrique; Frigon, Dominic

2014-04-15

Two pilot-scale activated sludge reactors were operated for 98 days to provide the necessary data to develop and validate a new mathematical model predicting the reduction of biosolids production by ozonation of the return activated sludge (RAS). Three ozone doses were tested during the study. In addition to the pilot-scale study, laboratory-scale experiments were conducted with mixed liquor suspended solids and with pure cultures to parameterize the biomass inactivation process during exposure to ozone. The experiments revealed that biomass inactivation occurred even at the lowest doses, but that it was not associated with extensive COD solubilization. For validation, the model was used to simulate the temporal dynamics of the pilot-scale operational data. Increasing the description accuracy of the inactivation process improved the precision of the model in predicting the operational data. Copyright © 2014 Elsevier B.V. All rights reserved.

Foucault, Surveillance, and Carbon Monoxide Testing Within Stop-Smoking Services

PubMed Central

Ashton, Kathryn; Phillips, Rhiannon

2015-01-01

Health professionals have adopted proactive testing for early evidence of disease. Researchers have identified that this leads to enumerated understandings and shapes behavior in productive ways. Smoking-cessation advisors regularly test clients for carbon monoxide (CO), but client views of this had not previously been explored. We interviewed 23 clients of a United Kingdom-based stop-smoking service regarding their experiences of CO testing. The majority of participants were successful quitters. We used ATLAS.ti 7 as a data-management tool during structured qualitative analysis. Our findings reveal that clients believed the results of their CO tests. Many became enumerated in their understanding, and thus placed themselves in a hierarchy with other members of their group. Almost all clients found that knowing their CO test score was motivating. We conclude that additional research is needed to understand the experiences of CO testing among clients who do not quit. PMID:25294348

Analyzing Single-Molecule Protein Transportation Experiments via Hierarchical Hidden Markov Models

PubMed Central

Chen, Yang; Shen, Kuang

2017-01-01

To maintain proper cellular functions, over 50% of proteins encoded in the genome need to be transported to cellular membranes. The molecular mechanism behind such a process, often referred to as protein targeting, is not well understood. Single-molecule experiments are designed to unveil the detailed mechanisms and reveal the functions of different molecular machineries involved in the process. The experimental data consist of hundreds of stochastic time traces from the fluorescence recordings of the experimental system. We introduce a Bayesian hierarchical model on top of hidden Markov models (HMMs) to analyze these data and use the statistical results to answer the biological questions. In addition to resolving the biological puzzles and delineating the regulating roles of different molecular complexes, our statistical results enable us to propose a more detailed mechanism for the late stages of the protein targeting process. PMID:28943680

Additive QTLs on three chromosomes control flowering time in woodland strawberry (Fragaria vesca L.)

PubMed Central

Samad, Samia; Kurokura, Takeshi; Koskela, Elli; Toivainen, Tuomas; Patel, Vipul; Mouhu, Katriina; Sargent, Daniel James; Hytönen, Timo

2017-01-01

Flowering time is an important trait that affects survival, reproduction and yield in both wild and cultivated plants. Therefore, many studies have focused on the identification of flowering time quantitative trait locus (QTLs) in different crops, and molecular control of this trait has been extensively investigated in model species. Here we report the mapping of QTLs for flowering time and vegetative traits in a large woodland strawberry mapping population that was phenotyped both under field conditions and in a greenhouse after flower induction in the field. The greenhouse experiment revealed additive QTLs in three linkage groups (LG), two on both LG4 and LG7, and one on LG6 that explain about half of the flowering time variance in the population. Three of the QTLs were newly identified in this study, and one co-localized with the previously characterized FvTFL1 gene. An additional strong QTL corresponding to previously mapped PFRU was detected in both field and greenhouse experiments indicating that gene(s) in this locus can control the timing of flowering in different environments in addition to the duration of flowering and axillary bud differentiation to runners and branch crowns. Several putative flowering time genes were identified in these QTL regions that await functional validation. Our results indicate that a few major QTLs may control flowering time and axillary bud differentiation in strawberries. We suggest that the identification of causal genes in the diploid strawberry may enable fine tuning of flowering time and vegetative growth in the closely related octoploid cultivated strawberry. PMID:28580150

Effects of air exposure, temperature and additives on fermentation characteristics, yeast count, aerobic stability and volatile organic compounds in corn silage.

PubMed

Weiss, K; Kroschewski, B; Auerbach, H

2016-10-01

Ensiling conditions strongly influence fermentation characteristics, yeast count, and aerobic stability. Numerous volatile organic compounds including esters are produced, which may negatively affect feed intake and animal performance and air quality. In addition to a farm survey, 3 laboratory experiments were carried out to study the effects of air (by delayed sealing or by air infiltration during anaerobic storage), temperature (20 and 35°C), and various types of additives [blends of either sodium benzoate and sodium propionate (SBSP) or of sodium benzoate and potassium sorbate (SBPS); buffered mixture of formic and propionic acids (FAPA); homofermentative inoculant (LAB)]. After additive treatment, chopped whole corn plants were packed into 1.5-L glass jars and stored for several months. For treatments with air infiltration, glass jars with holes in the lid and body were used. The farm survey in 2009 revealed large variation in lactate, acetate, ethanol, n-propanol, and 1,2-propanediol concentrations. Whereas ethyl esters were detected in all silages, the mean ethyl lactate concentrations were higher than those for ethyl acetate (474 vs. 38mg/kg of dry matter). In the ensiling experiments, few unequivocal effects of the tested factors on the analyzed parameters were observed due to many interactions. Delayed ensiling without additives decreased lactic acid production but, in one trial, increased acetic acid and had no effect on ethanol. The effect of delayed sealing on yeast counts and aerobic stability differed widely among experiments. Air infiltration during fermentation tested in one trial did not alter lactic acid production, but resulted in more acetic acid in delayed and more ethanol than in promptly sealed untreated silages. Greater ethanol production was associated with increased yeast numbers. Storage at high temperature resulted in lower lactic acid and n-propanol, and a trend toward reduced ethanol production was observed. The additive FAPA consistently caused increased ethanol and reduced n-propanol levels with no effect on yeast counts and aerobic stability. When the additives SBSP and SBPS decreased n-propanol and ethanol, reduced yeast counts were also found. Ethyl ester formation was strongly correlated with those of ethanol and to a lesser degree with those of the respective acid. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Individual differences in chess expertise: a psychometric investigation.

PubMed

Grabner, Roland H; Stern, Elsbeth; Neubauer, Aljoscha C

2007-03-01

Starting from controversies over the role of general individual characteristics (especially intelligence) for the attainment of expert performance levels, a comprehensive psychometric investigation of individual differences in chess expertise is presented. A sample of 90 adult tournament chess players of varying playing strengths (1311-2387 ELO) was screened with tests on intelligence and personality variables; in addition, experience in chess play, tournament participation, and practice activities were assessed. Correlation and regression analyses revealed a clear-cut moderate relationship between general (and in particular numerical) intelligence and the participants' playing strengths, suggesting that expert chess play does not stand in isolation from superior mental abilities. The strongest predictor of the attained expertise level, however, was the participants' chess experience which highlights the relevance of long-term engagement for the development of expertise. Among all analysed personality dimensions, only domain-specific performance motivation and emotion expression control incrementally contributed to the prediction of playing strength. In total, measures of chess experience, current tournament activity, intelligence, and personality accounted for about 55% of variance in chess expertise. The present results suggest that individual differences in chess expertise are multifaceted and cannot be reduced to differences in domain experience.

Beyond procedure's content: the role of accessibility experiences and personal uncertainty in procedural justice judgements.

PubMed

Greifeneder, Rainer; Müller, Patrick; Stahlberg, Dagmar; Van den Bos, Kees; Bless, Herbert

2011-01-01

Procedural justice concerns play a critical role in economic settings, politics, and other domains of human life. Despite the vast evidence corroborating their relevance, considerably less is known about how procedural justice judgments are formed. Whereas earlier theorizing focused on the systematic integration of content information, the present contribution provides a new perspective on the formation of justice judgments by examining the influence of accessibility experiences. Specifically, we hypothesize that procedural justice judgments may be formed based on the ease or difficulty with which justice-relevant information comes to mind. Three experiments corroborate this prediction in that procedures were evaluated less positively when the retrieval of associated unfair aspects was easy compared to difficult. Presumably this is because when it feels easy (difficult) to retrieve unfair aspects, these are perceived as frequent (infrequent), and hence the procedure as unjust (just). In addition to demonstrating that ease-of-retrieval may influence justice judgments, the studies further revealed that reliance on accessibility experiences is high in conditions of personal certainty. We suggest that this is because personal uncertainty fosters systematic processing of content information, whereas personal certainty may invite less taxing judgmental strategies such as reliance on ease-of-retrieval.

A study of ayahuasca use in North America.

PubMed

Harris, Rachel; Gurel, Lee

2012-01-01

Eighty-one subjects who used ayahuasca at least once in North America answered a lengthy set of open-ended questions and completed the 81-item After the Spiritual Experience Questionnaire. An additional 50 ayahuasca users were interviewed in person. The data for this study represent ayahuasca experience based on more than 2,267 ceremonies. A comparison group of 46 people attending a Catholic spiritual retreat weekend also completed the After the Spiritual Experience Questionnaire. A factor analysis of this questionnaire yielded three factors: Joy in Life, Relationship to the Sacred and Toxic Feelings. Although the ayahuasca users had significantly higher scores on the first two factors, the two groups had modest mean differences indicating a similar response to two very different spiritual experiences. This key finding strongly supports the view that ayahuasca users are engaged in an authentic process as spiritual in nature as that of the retreatants. The qualitative data revealed that ayahuasca users reduced their alcohol intake, ate healthier diets, enjoyed improved mood and greater self-acceptance and felt more loving and compassionate in their relationships. Seventy-four percent of the ayahuasca users said they had a relationship with and received ongoing guidance and support from the spirit of ayahuasca.

Model Fit to Experimental Data for Foam-Assisted Deep Vadose Zone Remediation

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

Roostapour, A.; Lee, G.; Zhong, Lirong

2014-01-15

Foam has been regarded as a promising means of remeidal amendment delivery to overcome subsurface heterogeneity in subsurface remediation processes. This study investigates how a foam model, developed by Method of Characteristics and fractional flow analysis in the companion paper of Roostapour and Kam (2012), can be applied to make a fit to a set of existing laboratory flow experiments (Zhong et al., 2009) in an application relevant to deep vadose zone remediation. This study reveals a few important insights regarding foam-assisted deep vadose zone remediation: (i) the mathematical framework established for foam modeling can fit typical flow experiments matchingmore » wave velocities, saturation history , and pressure responses; (ii) the set of input parameters may not be unique for the fit, and therefore conducting experiments to measure basic model parameters related to relative permeability, initial and residual saturations, surfactant adsorption and so on should not be overlooked; and (iii) gas compressibility plays an important role for data analysis, thus should be handled carefully in laboratory flow experiments. Foam kinetics, causing foam texture to reach its steady-state value slowly, may impose additional complications.« less

The relationship between semantic short-term memory and immediate serial recall of known and unknown words and nonwords: data from two Chinese individuals with aphasia.

PubMed

Wong, Winsy; Low, Sam-Po

2008-07-01

The present study investigated verbal recall of semantically preserved and degraded words and nonwords by taking into consideration the status of one's semantic short-term memory (STM). Two experiments were conducted on 2 Chinese individuals with aphasia. The first experiment showed that they had largely preserved phonological processing abilities accompanied by mild but comparable semantic processing deficits; however, their performance on STM tasks revealed a double dissociation. The second experiment found that the participant with more preserved semantic STM had better recall of known words and nonwords than of their unknown counterparts, whereas such effects were absent in the patient with severe semantic STM deficit. The results are compatible with models that assume separate phonological and semantic STM components, such as that of R. C. Martin, M. Lesch, and M. Bartha (1999). In addition, the distribution of error types was different from previous studies. This is discussed in terms of the methodology of the authors' experiments and current views regarding the nature of semantic STM and representations in the Chinese mental lexicon. (c) 2008 APA

Female Sexual Victimization Among College Students: Assault Severity, Health Risk Behaviors, and Sexual Functioning.

PubMed

Turchik, Jessica A; Hassija, Christina M

2014-09-01

The purpose of the present study was to examine the relationship between college women's sexual victimization experiences, health risk behaviors, and sexual functioning. A sample of 309 college women at a mid-sized Midwestern university completed measures assessing sexual victimization, sexual risk taking, substance use behaviors, sexual desire, sexual functioning, prior sexual experiences, and social desirability. Severity of sexual victimization was measured using a multi-item, behaviorally specific, gender-neutral measure, which was divided into four categories based on severity (none, sexual contact, sexual coercion, rape). Within the sample, 72.8% (n = 225) of women reported at least one experience of sexual victimization since age 16. Results from MANCOVAs and a multinomial logistic regression, controlling for social desirability and prior sexual experience, revealed that sexual victimization among female students was related to increased drug use, problematic drinking behaviors, sexual risk taking, sexual dysfunction, and dyadic sexual desire. In addition, findings indicated that women exposed to more severe forms of sexual victimization (i.e., rape) were most likely to report these risk-taking behaviors and sexual functioning issues. Implications for sexual assault risk reduction programming and treatment are discussed. © The Author(s) 2014.

Comparing the Performances of Apes (Gorilla gorilla, Pan troglodytes, Pongo pygmaeus) and Human Children (Homo sapiens) in the Floating Peanut Task

PubMed Central

Hanus, Daniel; Mendes, Natacha; Tennie, Claudio; Call, Josep

2011-01-01

Recently, Mendes et al. [1] described the use of a liquid tool (water) in captive orangutans. Here, we tested chimpanzees and gorillas for the first time with the same “floating peanut task.” None of the subjects solved the task. In order to better understand the cognitive demands of the task, we further tested other populations of chimpanzees and orangutans with the variation of the peanut initially floating or not. Twenty percent of the chimpanzees but none of the orangutans were successful. Additional controls revealed that successful subjects added water only if it was necessary to obtain the nut. Another experiment was conducted to investigate the reason for the differences in performance between the unsuccessful (Experiment 1) and the successful (Experiment 2) chimpanzee populations. We found suggestive evidence for the view that functional fixedness might have impaired the chimpanzees' strategies in the first experiment. Finally, we tested how human children of different age classes perform in an analogous experimental setting. Within the oldest group (8 years), 58 percent of the children solved the problem, whereas in the youngest group (4 years), only 8 percent were able to find the solution. PMID:21687710

Comparing the performances of apes (Gorilla gorilla, Pan troglodytes, Pongo pygmaeus) and human children (Homo sapiens) in the floating peanut task.

PubMed

Hanus, Daniel; Mendes, Natacha; Tennie, Claudio; Call, Josep

2011-01-01

Recently, Mendes et al. [1] described the use of a liquid tool (water) in captive orangutans. Here, we tested chimpanzees and gorillas for the first time with the same "floating peanut task." None of the subjects solved the task. In order to better understand the cognitive demands of the task, we further tested other populations of chimpanzees and orangutans with the variation of the peanut initially floating or not. Twenty percent of the chimpanzees but none of the orangutans were successful. Additional controls revealed that successful subjects added water only if it was necessary to obtain the nut. Another experiment was conducted to investigate the reason for the differences in performance between the unsuccessful (Experiment 1) and the successful (Experiment 2) chimpanzee populations. We found suggestive evidence for the view that functional fixedness might have impaired the chimpanzees' strategies in the first experiment. Finally, we tested how human children of different age classes perform in an analogous experimental setting. Within the oldest group (8 years), 58 percent of the children solved the problem, whereas in the youngest group (4 years), only 8 percent were able to find the solution.

Designing experiments on thermal interactions by secondary-school students in a simulated laboratory environment

NASA Astrophysics Data System (ADS)

Lefkos, Ioannis; Psillos, Dimitris; Hatzikraniotis, Euripides

2011-07-01

Background and purpose: The aim of this study was to explore the effect of investigative activities with manipulations in a virtual laboratory on students' ability to design experiments. Sample Fourteen students in a lower secondary school in Greece attended a teaching sequence on thermal phenomena based on the use of information and communication technology, and specifically of the simulated virtual laboratory 'ThermoLab'. Design and methods A pre-post comparison was applied. Students' design of experiments was rated in eight dimensions; namely, hypothesis forming and verification, selection of variables, initial conditions, device settings, materials and devices used, process and phenomena description. A three-level ranking scheme was employed for the evaluation of students' answers in each dimension. Results A Wilcoxon signed-rank test revealed a statistically significant difference between the students' pre- and post-test scores. Additional analysis by comparing the pre- and post-test scores using the Hake gain showed high gains in all but one dimension, which suggests that this improvement was almost inclusive. Conclusions We consider that our findings support the statement that there was an improvement in students' ability to design experiments.

Performance anxiety experiences of professional ballet dancers: the importance of control.

PubMed

Walker, Imogen J; Nordin-Bates, Sanna M

2010-01-01

Performance anxiety research abounds in sport psychology, yet has been relatively sparse in dance. The present study explores ballet dancers' experiences of performance anxiety in relation to: 1. symptom type, intensity, and directional interpretation; 2. experience level (including company rank); and 3. self-confidence and psychological skills. Fifteen elite ballet dancers representing all ranks in one company were interviewed, and qualitative content analysis was conducted. Results revealed that cognitive anxiety was more dominant than somatic anxiety, and was unanimously interpreted as debilitative to performance. Somatic anxiety was more likely to be interpreted as facilitative, with the majority of dancers recognizing that a certain amount of anxiety could be beneficial to performance. Principal dancers suffered from higher intensities of performance anxiety than corps de ballet members. Feeling out of control emerged as a major theme in both the experience of anxiety and its interpretation. As a result, prevention or handling of anxiety symptoms may be accomplished by helping dancers to feel in control. Dancers may benefit from education about anxiety symptoms and their interpretation, in addition to psychological skills training incorporating cognitive restructuring strategies and problem-focussed coping to help increase their feelings of being in control.

Motherhood in the shade of migration: A qualitative study of the experience of Syrian refugee mothers living in Turkey.

PubMed

Korukcu, Oznur; Aydın, Ruveyde; Conway, Jane; Kukulu, Kamile

2018-03-01

Turkey receives the largest number of Syrian refugees in the world. Some of these refugee women become mothers in Turkey. This paper reports on a qualitative, descriptive study that investigated the experience of seven Syrian women migrants who gave birth in Turkey, and explores their experiences of transition to motherhood in a foreign country. The research identified that aspects of transition can be clustered under five main themes: difficulties during the pregnancy period, giving birth in a foreign country, problems of refugee mothers, milestones in life of refugee mothers, and influence of cultural beliefs of refugee mothers on baby care. Key findings revealed that the women in the study had negative experiences related to being pregnant and having a baby in a foreign country. In addition to identifying challenges associated with migration, such as language barriers, racism, discrimination, poverty, and separation from their culture and family, the study highlighted the fears and difficulties experienced by refugee mothers, the cultural beliefs of refugee women about caring for their babies, and turning points in the life of refugee mothers. © 2017 John Wiley & Sons Australia, Ltd.

Ebselen induces reactive oxygen species (ROS)-mediated cytotoxicity in Saccharomyces cerevisiae with inhibition of glutamate dehydrogenase being a target.

PubMed

Azad, Gajendra Kumar; Singh, Vikash; Mandal, Papita; Singh, Prabhat; Golla, Upendarrao; Baranwal, Shivani; Chauhan, Sakshi; Tomar, Raghuvir S

2014-01-01

Ebselen is a synthetic, lipid-soluble seleno-organic compound. The high electrophilicity of ebselen enables it to react with multiple cysteine residues of various proteins. Despite extensive research on ebselen, its target molecules and mechanism of action remains less understood. We performed biochemical as well as in vivo experiments employing budding yeast as a model organism to understand the mode of action of ebselen. The growth curve analysis and FACS (florescence activated cell sorting) assays revealed that ebselen exerts growth inhibitory effects on yeast cells by causing a delay in cell cycle progression. We observed that ebselen exposure causes an increase in intracellular ROS levels and mitochondrial membrane potential, and that these effects were reversed by addition of antioxidants such as reduced glutathione (GSH) or N-acetyl-l-cysteine (NAC). Interestingly, a significant increase in ROS levels was noticed in gdh3-deleted cells compared to wild-type cells. Furthermore, we showed that ebselen inhibits GDH function by interacting with its cysteine residues, leading to the formation of inactive hexameric GDH. Two-dimensional gel electrophoresis revealed protein targets of ebselen including CPR1, the yeast homolog of Cyclophilin A. Additionally, ebselen treatment leads to the inhibition of yeast sporulation. These results indicate a novel direct connection between ebselen and redox homeostasis.

Codon-Resolution Analysis Reveals a Direct and Context-Dependent Impact of Individual Synonymous Mutations on mRNA Level

PubMed Central

Chen, Siyu; Li, Ke; Cao, Wenqing; Wang, Jia; Zhao, Tong; Huan, Qing; Yang, Yu-Fei; Wu, Shaohuan; Qian, Wenfeng

2017-01-01

Abstract Codon usage bias (CUB) refers to the observation that synonymous codons are not used equally frequently in a genome. CUB is stronger in more highly expressed genes, a phenomenon commonly explained by stronger natural selection on translational accuracy and/or efficiency among these genes. Nevertheless, this phenomenon could also occur if CUB regulates gene expression at the mRNA level, a hypothesis that has not been tested until recently. Here, we attempt to quantify the impact of synonymous mutations on mRNA level in yeast using 3,556 synonymous variants of a heterologous gene encoding green fluorescent protein (GFP) and 523 synonymous variants of an endogenous gene TDH3. We found that mRNA level was positively correlated with CUB among these synonymous variants, demonstrating a direct role of CUB in regulating transcript concentration, likely via regulating mRNA degradation rate, as our additional experiments suggested. More importantly, we quantified the effects of individual synonymous mutations on mRNA level and found them dependent on 1) CUB and 2) mRNA secondary structure, both in proximal sequence contexts. Our study reveals the pleiotropic effects of synonymous codon usage and provides an additional explanation for the well-known correlation between CUB and gene expression level. PMID:28961875

Effects of test method and participant musical training on preference ratings of stimuli with different reverberation times.

PubMed

Lawless, Martin S; Vigeant, Michelle C

2017-10-01

Selecting an appropriate listening test design for concert hall research depends on several factors, including listening test method and participant critical-listening experience. Although expert listeners afford more reliable data, their perceptions may not be broadly representative. The present paper contains two studies that examined the validity and reliability of the data obtained from two listening test methods, a successive and a comparative method, and two types of participants, musicians and non-musicians. Participants rated their overall preference of auralizations generated from eight concert hall conditions with a range of reverberation times (0.0-7.2 s). Study 1, with 34 participants, assessed the two methods. The comparative method yielded similar results and reliability as the successive method. Additionally, the comparative method was rated as less difficult and more preferable. For study 2, an additional 37 participants rated the stimuli using the comparative method only. An analysis of variance of the responses from both studies revealed that musicians are better than non-musicians at discerning their preferences across stimuli. This result was confirmed with a k-means clustering analysis on the entire dataset that revealed five preference groups. Four groups exhibited clear preferences to the stimuli, while the fifth group, predominantly comprising non-musicians, demonstrated no clear preference.

Proboscis Conditioning Experiments with Honeybees, Apis Mellifera Caucasica, with Butyric Acid and DEET Mixture as Conditioned and Unconditioned Stimuli

PubMed Central

Abramson, Charles I.; Giray, Tugrul; Mixson, T. Andrew; Nolf, Sondra L.; Wells, Harrington; Kence, Aykut; Kence, Meral

2010-01-01

Three experiments are described investigating whether olfactory repellents DEET and butyric acid can support the classical conditioning of proboscis extension in the honeybee, Apis mellifera caucasica (Hymenoptera: Apidae). In the first experiment DEET and butyric acid readily led to standard acquisition and extinction effects, which are comparable to the use of cinnamon as a conditioned stimulus. These results demonstrate that the odor of DEET or butyric acid is not intrinsically repellent to honey bees. In a second experiment, with DEET and butyric acid mixed with sucrose as an unconditioned stimulus, proboscis conditioning was not established. After several trials, few animals responded to the unconditioned stimulus. These results demonstrate that these chemicals are gustatory repellents when in direct contact. In the last experiment a conditioned suppression paradigm was used. Exposing animals to butyric acid or DEET when the proboscis was extended by direct sucrose stimulation or by learning revealed that retraction of the proboscis was similar to another novel odor, lavender, and in all cases greatest when the animal was not permitted to feed. These results again demonstrate that DEET or butyric acid are not olfactory repellents, and in addition, conditioned suppression is influenced by feeding state of the bee. PMID:20879917

Proboscis conditioning experiments with honeybees, Apis mellifera caucasica, with butyric acid and DEET mixture as conditioned and unconditioned stimuli.

PubMed

Abramson, Charles I; Giray, Tugrul; Mixson, T Andrew; Nolf, Sondra L; Wells, Harrington; Kence, Aykut; Kence, Meral

2010-01-01

Three experiments are described investigating whether olfactory repellents DEET and butyric acid can support the classical conditioning of proboscis extension in the honeybee, Apis mellifera caucasica (Hymenoptera: Apidae). In the first experiment DEET and butyric acid readily led to standard acquisition and extinction effects, which are comparable to the use of cinnamon as a conditioned stimulus. These results demonstrate that the odor of DEET or butyric acid is not intrinsically repellent to honey bees. In a second experiment, with DEET and butyric acid mixed with sucrose as an unconditioned stimulus, proboscis conditioning was not established. After several trials, few animals responded to the unconditioned stimulus. These results demonstrate that these chemicals are gustatory repellents when in direct contact. In the last experiment a conditioned suppression paradigm was used. Exposing animals to butyric acid or DEET when the proboscis was extended by direct sucrose stimulation or by learning revealed that retraction of the proboscis was similar to another novel odor, lavender, and in all cases greatest when the animal was not permitted to feed. These results again demonstrate that DEET or butyric acid are not olfactory repellents, and in addition, conditioned suppression is influenced by feeding state of the bee.

What I experienced yesterday is who I am today: relationship of work motivations and behaviors to within-individual variation in the five-factor model of personality.

PubMed

Judge, Timothy A; Simon, Lauren S; Hurst, Charlice; Kelley, Ken

2014-03-01

Historically, organizational and personality psychologists have ignored within-individual variation in personality across situations or have treated it as measurement error. However, we conducted a 10-day experience sampling study consistent with whole trait theory (Fleeson, 2012), which conceptualizes personality as a system of stable tendencies and patterns of intraindividual variation along the dimensions of the Big Five personality traits (Costa & McCrae, 1992). The study examined whether (a) internal events (i.e., motivation), performance episodes, and interpersonal experiences at work predict deviations from central tendencies in trait-relevant behavior, affect, and cognition (i.e., state personality), and (b) there are individual differences in responsiveness to work experiences. Results revealed that personality at work exhibited both stability and variation within individuals. Trait measures predicted average levels of trait manifestation in daily behavior at work, whereas daily work experiences (i.e., organizational citizenship, interpersonal conflict, and motivation) predicted deviations from baseline tendencies. Additionally, correlations of neuroticism with standard deviations in the daily personality variables suggest that, although work experiences influence state personality, people higher in neuroticism exhibit higher levels of intraindividual variation in personality than do those who are more emotionally stable.

Links between Family Gender Socialization Experiences in Childhood and Gendered Occupational Attainment in Young Adulthood

PubMed Central

Lawson, Katie M.; Crouter, Ann C.; McHale, Susan M.

2015-01-01

Gendered occupational segregation remains prevalent across the world. Although research has examined factors contributing to the low number of women in male-typed occupations – namely science, technology, engineering, and math – little longitudinal research has examined the role of childhood experiences in both young women’s and men’s later gendered occupational attainment. This study addressed this gap in the literature by examining family gender socialization experiences in middle childhood – namely parents’ attitudes and work and family life – as contributors to the gender typicality of occupational attainment in young adulthood. Using data collected from mothers, fathers, and children over approximately 15 years, the results revealed that the associations between childhood socialization experiences (∼10 years old) and occupational attainment (∼26 years old) depended on the sex of the child. For sons but not daughters, mothers’ more traditional attitudes towards women’s roles predicted attaining more gender-typed occupations. In addition, spending more time with fathers in childhood predicted daughters attaining less and sons acquiring more gender-typed occupations in young adulthood. Overall, evidence supports the idea that childhood socialization experiences help to shape individuals’ career attainment and thus contribute to gender segregation in the labor market. PMID:26977112

Photoinduced Oxidative DNA Damage Revealed by an Agarose Gel Nicking Assay: A Biophysical Chemistry Laboratory Experiment

NASA Astrophysics Data System (ADS)

Shafirovich, Vladimir; Singh, Carolyn; Geacintov, Nicholas E.

2003-11-01

Oxidative damage of DNA molecules associated with electron-transfer reactions is an important phenomenon in living cells, which can lead to mutations and contribute to carcinogenesis and the aging processes. This article describes the design of several simple experiments to explore DNA damage initiated by photoinduced electron-transfer reactions sensitized by the acridine derivative, proflavine (PF). A supercoiled DNA agarose gel nicking assay is employed as a sensitive probe of DNA strand cleavage. A low-cost experimental and computer-interfaced imaging apparatus is described allowing for the digital recording and analysis of the gel electrophoresis results. The first experiment describes the formation of direct strand breaks in double-stranded DNA induced by photoexcitation of the intercalated PF molecules. The second experiment demonstrates that the addition of the well-known electron acceptor, methylviologen, gives rise to a significant enhancement of the photochemical DNA strand cleavage effect. This occurs by an electron transfer step to methylviologen that renders the inital photoinduced charge separation between photoexcited PF and DNA irreversible. The third experiment demonstrates that the action spectrum of the DNA photocleavage matches the absorption spectrum of DNA-bound, intercalated PF molecules, which differs from that of free PF molecules. This result demonstrates that the photoinduced DNA strand cleavage is initiated by intercalated rather than free PF molecules.

The development of prospective memory in young schoolchildren: the impact of ongoing task absorption, cue salience, and cue centrality.

PubMed

Kliegel, Matthias; Mahy, Caitlin E V; Voigt, Babett; Henry, Julie D; Rendell, Peter G; Aberle, Ingo

2013-12-01

This study presents evidence that 9- and 10-year-old children outperform 6- and 7-year-old children on a measure of event-based prospective memory and that retrieval-based factors systematically influence performance and age differences. All experiments revealed significant age effects in prospective memory even after controlling for ongoing task performance. In addition, the provision of a less absorbing ongoing task (Experiment 1), higher cue salience (Experiment 2), and cues appearing in the center of attention (Experiment 3) were each associated with better performance. Of particular developmental importance was an age by cue centrality (in or outside of the center of attention) interaction that emerged in Experiment 3. Thus, age effects were restricted to prospective memory cues appearing outside of the center of attention, suggesting that the development of prospective memory across early school years may be modulated by whether a cue requires overt monitoring beyond the immediate attentional context. Because whether a cue is in or outside of the center of attention might determine the amount of executive control needed in a prospective memory task, findings suggest that developing executive control resources may drive prospective memory development across primary school age. Copyright © 2013 Elsevier Inc. All rights reserved.

Inter- and intraexaminer reliability of bitewing radiography and near-infrared light transillumination for proximal caries detection and assessment.

PubMed

Litzenburger, Friederike; Heck, Katrin; Pitchika, Vinay; Neuhaus, Klaus W; Jost, Fabian N; Hickel, Reinhard; Jablonski-Momeni, Anahita; Welk, Alexander; Lederer, Alexander; Kühnisch, Jan

2018-02-01

The purpose of this in vitro study was to evaluate the inter- and intraexaminer reliability of digital bitewing (DBW) radiography and near-infrared light transillumination (NIRT) for proximal caries detection and assessment in posterior teeth. From a pool of 85 patients, 100 corresponding pairs of DBW and NIRT images (~1/3 healthy, ~1/3 with enamel caries and ~1/3 with dentin caries) were chosen. 12 dentists with different professional status and clinical experience repeated the evaluation in two blinded cycles. Two experienced dentists provided a reference diagnosis after analysing all images independently. Statistical analysis included the calculation of simple (κ) and weighted Kappa (wκ) values as a measure of reliability. Logistic regression with a backward elimination model was used to investigate the influence of the diagnostic method, evaluation cycle, type of tooth, and clinical experience on reliability. Altogether, inter- and intraexaminer reliability exhibited good to excellent κ and wκ values for DBW radiography (Inter: κ = 0.60/ 0.63; wκ = 0.74/0.76; Intra: κ = 0.64; wκ = 0.77) and NIRT (Inter: κ = 0.74/0.64; wκ = 0.86/0.82; Intra: κ = 0.68; wκ = 0.84). The backward elimination model revealed NIRT to be significantly more reliable than DBW radiography. This study revealed a good to excellent inter- and intraexaminer reliability for proximal caries detection using DBW and NIRT images. The logistic regression analysis revealed significantly better reliability for NIRT. Additionally, the first evaluation cycle was more reliable according to the reference diagnoses.

Biosynthetic Investigations of Lactonamycin and Lactonamycin Z: Cloning of the Biosynthetic Gene Clusters and Discovery of an Unusual Starter Unit▿ †

PubMed Central

Zhang, Xiujun; Alemany, Lawrence B.; Fiedler, Hans-Peter; Goodfellow, Michael; Parry, Ronald J.

2008-01-01

The antibiotics lactonamycin and lactonamycin Z provide attractive leads for antibacterial drug development. Both antibiotics contain a novel aglycone core called lactonamycinone. To gain insight into lactonamycinone biosynthesis, cloning and precursor incorporation experiments were undertaken. The lactonamycin gene cluster was initially cloned from Streptomyces rishiriensis. Sequencing of ca. 61 kb of S. rishiriensis DNA revealed the presence of 57 open reading frames. These included genes coding for the biosynthesis of l-rhodinose, the sugar found in lactonamycin, and genes similar to those in the tetracenomycin biosynthetic gene cluster. Since lactonamycin production by S. rishiriensis could not be sustained, additional proof for the identity of the S. rishiriensis cluster was obtained by cloning the lactonamycin Z gene cluster from Streptomyces sanglieri. Partial sequencing of the S. sanglieri cluster revealed 15 genes that exhibited a very high degree of similarity to genes within the lactonamycin cluster, as well as an identical organization. Double-crossover disruption of one gene in the S. sanglieri cluster abolished lactonamycin Z production, and production was restored by complementation. These results confirm the identity of the genetic locus cloned from S. sanglieri and indicate that the highly similar locus in S. rishiriensis encodes lactonamycin biosynthetic genes. Precursor incorporation experiments with S. sanglieri revealed that lactonamycinone is biosynthesized in an unusual manner whereby glycine or a glycine derivative serves as a starter unit that is extended by nine acetate units. Analysis of the gene clusters and of the precursor incorporation data suggested a hypothetical scheme for lactonamycinone biosynthesis. PMID:18070976

Surface, Water, and Air Biocharacterization (SWAB) Flight Experiment

NASA Technical Reports Server (NTRS)

Castro, V. A.; Ott, C. M.; Pierson, D. L.

2012-01-01

The determination of risk from infectious disease during spaceflight missions is composed of several factors including both the concentration and characteristics of the microorganisms to which the crew are exposed. Thus, having a good understanding of the microbial ecology aboard spacecraft provides the necessary information to mitigate health risks to the crew. While preventive measures are taken to minimize the presence of pathogens on spacecraft, medically significant organisms have been isolated from both the Mir and International Space Station (ISS). Historically, the method for isolation and identification of microorganisms from spacecraft environmental samples depended upon their growth on culture media. Unfortunately, only a fraction of the organisms may grow on a specific culture medium, potentially omitting those microorganisms whose nutritional and physical requirements for growth are not met. To address this bias in our understanding of the ISS environment, the Surface, Water, and Air Biocharacterization (SWAB) Flight Experiment was designed to investigate and develop monitoring technology to provide better microbial characterization. For the SWAB flight experiment, we hypothesized that environmental analysis using non-culture-based technologies would reveal microorganisms, allergens, and microbial toxins not previously reported in spacecraft, allowing for a more complete health assessment. Key findings during this experiment included: a) Generally, advanced molecular techniques were able to reveal a few organisms not recovered using culture-based methods; however, there is no indication that current monitoring is "missing" any medically significant bacteria or fungi. b) Molecular techniques have tremendous potential for microbial monitoring, however, sample preparation and data analysis present challenges for spaceflight hardware. c) Analytical results indicate that some molecular techniques, such as denaturing gradient gel electrophoresis (DGGE), can be much less sensitive than culture-based methods. d) More sensitive molecular techniques, such as quantitative polymerase chain reaction (QPCR), were able to identify viral DNA from ISS environments, suggesting potential transfer of the organism between crewmembers. In addition, the hardware selected for this experiment represented advances for next-generation sample collection. The advanced nature of this collection hardware was noted, when the Sartorius MD8 Air Port air sampler from the SWAB experiment remained on board ISS at the request of JAXA investigators, who intend to use it in completion of their microbial ecology experiment.

Student journals: a means of assessing transformative learning in aging related courses.

PubMed

Cohen, Adrienne L; Pitman Brown, Pamela; Morales, Justin P

2015-01-01

In courses where topics are sensitive or even considered taboo for discussion, it can be difficult to assess students' deeper learning. In addition, incorporating a wide variety of students' values and beliefs, designing instructional strategies and including varied assessments adds to the difficulty. Journal entries or response notebooks can highlight reflection upon others' viewpoints, class readings, and additional materials. These are useful across all educational levels in deep learning and comprehension strategies assessments. Journaling meshes with transformative learning constructs, allowing for critical self-reflection essential to transformation. Qualitative analysis of journals in a death and dying class reveals three transformative themes: awareness of others, questioning, and comfort. Students' journal entries demonstrate transformative learning via communication with others through increased knowledge/exposure to others' experiences and comparing/contrasting others' personal beliefs with their own. Using transformative learning within gerontology and geriatrics education, as well as other disciplined aging-related courses is discussed.

Influence of polysaccharides on wine protein aggregation.

PubMed

Jaeckels, Nadine; Meier, Miriam; Dietrich, Helmut; Will, Frank; Decker, Heinz; Fronk, Petra

2016-06-01

Polysaccharides are the major high-molecular weight components of wines. In contrast, proteins occur only in small amounts in wine, but contribute to haze formation. The detailed mechanism of aggregation of these proteins, especially in combination with other wine components, remains unclear. This study demonstrates the different aggregation behavior between a buffer and a model wine system by dynamic light scattering. Arabinogalactan-protein, for example, shows an increased aggregation in the model wine system, while in the buffer system a reducing effect is observed. Thus, we could show the importance to examine the behavior of wine additives under conditions close to reality, instead of simpler buffer systems. Additional experiments on melting points of wine proteins reveal that only some isoforms of thaumatin-like proteins and chitinases are involved in haze formation. We can confirm interactions between polysaccharides and proteins, but none of these polysaccharides is able to prevent haze in wine. Copyright © 2016. Published by Elsevier Ltd.

Toughening epoxy acrylate with polyurethane acrylates and hyper-branched polyester in three dimensional printing

NASA Astrophysics Data System (ADS)

Fang, Chao; Li, Ning; Liu, Yang; Lu, Gang

2018-05-01

In order to improve the toughness of epoxy acrylate (EA) in three dimensional printing (3D-printing), bifunctional polyurethane acrylate (PUA) and trifunctional PUA were firstly blended with EA. The multi-indicators orthogonal experiment, designed with the indicators of tensile strength, elongation at break and impact strength, was used to find out the optimal formulation. Then, hyper-branched polyesters (HBPs) was added to improve the toughness of the photocurable system. The microstructures of the cured specimens were characterized by optical microscopy and scanning electron microscopy. By analyzing their mechanical properties and microstructures, it was revealed that the best addition amounts of HBP are 10 wt%. Results indicated that their toughness improved a lot comparing with pure EA. The changes of mechanical properties were characterized by DMA. The addition of HBP could cause a loss in stiffness, elasticity modulus and thermostability.

Access to enantioenriched alpha-amino esters via rhodium-catalyzed 1,4-addition/enantioselective protonation.

PubMed

Navarre, Laure; Martinez, Rémi; Genet, Jean-Pierre; Darses, Sylvain

2008-05-14

Conjugate addition of potassium trifluoro(organo)borates 2 to dehydroalanine derivatives 1, mediated by a chiral rhodium catalyst and in situ enantioselective protonation, afforded straightforward access to a variety of protected alpha-amino esters 3 with high yields and enantiomeric excesses up to 95%. Among the tested chiral ligands and proton sources, Binap, in combination with guaiacol (2-methoxyphenol), an inexpensive and nontoxic phenol, afforded the highest asymmetric inductions. Organostannanes have also shown to participate in this reaction. By a fine-tuning of the ester moiety, and using Difluorophos as chiral ligand, increased levels of enantioselectivity, generally close to 95%, were achieved. Deuterium labeling experiments revealed, and DFT calculation supported, an unusual mechanism involving a hydride transfer from the amido substituent to the alpha carbon explaining the high levels of enantioselectivity attained in controlling this alpha chiral center.

Forecast skill impact of drifting buoys in the Southern Hemisphere

NASA Technical Reports Server (NTRS)

Kalnay, E.; Atlas, R.; Baker, W.; Halem, M.

1984-01-01

Two analyses are performed to evaluate the effect of drift buoys and the FGGE's special observing system (SOS) on forecasting. The FGGE analysis utilizes all level II-b conventional and special data, and the Nosat analysis employs only surface and conventional upper air data. Twelve five-day forecasts are produced from these data. An additional experiment utilizing the FGGE data base minus buoys data, and the Nosat data base including buoys data is being conducted. The forecasts are compared and synoptic evaluation of the effect of buoys data is described. The results reveal that the FGGE data base with the SOS significantly improves forecasting in the Southern Hemisphere and the loss of buoys data does not have a great effect on forecasting. The Nosat data has less impact on forecasting; however, the addition of buoys data provides an improvement in forecast skills.

A high selective anion colorimetric sensor based on salicylaldehyde for fluoride in aqueous media.

PubMed

Li, Jianwei; Lin, Hai; Cai, Zunsheng; Lin, Huakuan

2009-06-01

A new and simple salicylaldehyde-based sensor 1 designed for fluoride sensing has been investigated in DMSO and even in the 9/1 DMSO/H(2)O (v/v) mixtures. The affinity constants of receptor 1 for anionic species in the 9/1 DMSO/H(2)O (v/v) reveal that it is sensitive to F. Also, the color changes induced by anions can provide a way of detection by 'naked-eye'. These result can be substantiated by the spectrum changes upon the addition of 25equiv. anions to 1 in the 9/1 DMSO/H(2)O solution. The further insights to the nature of interactions between the sensor 1 and F(-) were investigated by (1)H NMR titration experiments in 9/1 DMSO-d(6)/H(2)O (v/v). In addition, the proposed binding mode between 1 and F(-) was suggested.

Nanohybrid conjugated polyelectrolytes: highly photostable and ultrabright nanoparticles.

PubMed

Darwish, Ghinwa H; Karam, Pierre

2015-10-07

We present a general and straightforward one-step approach to enhance the photophysical properties of conjugated polyelectrolytes. Upon complexation with an amphiphilic polymer (polyvinylpyrrolidone), an anionic conjugated polyelectrolyte (poly[5-methoxy-2-(3-sulfopropoxy)-1,4-phenylenevinylene]) was prepared into small nanoparticles with exceptional photostability and brightness. The polymer fluorescence intensity was enhanced by 23 -fold and could be easily tuned by changing the order of addition. Single molecule experiments revealed a complete suppression of blinking. In addition, after only losing 18% of the original intensity, a remarkable amount of photons were emitted per particle (∼10(9), on average). This number is many folds greater than popular organic fluorescent dyes. We believe that an intimate contact between the two polymers is shielding the conjugated polyelectrolyte from the destructive photooxidation. The prepared nanohybrid particles will prove instrumental in single particle based fluorescent assays and can serve as a probe for the current state-of-the-art bioimaging fluorescence techniques.

Investigation into the influence of build parameters on failure of 3D printed parts

NASA Astrophysics Data System (ADS)

Fornasini, Giacomo

Additive manufacturing, including fused deposition modeling (FDM), is transforming the built world and engineering education. Deep understanding of parts created through FDM technology has lagged behind its adoption in home, work, and academic environments. Properties of parts created from bulk materials through traditional manufacturing are understood well enough to accurately predict their behavior through analytical models. Unfortunately, Additive Manufacturing (AM) process parameters create anisotropy on a scale that fundamentally affects the part properties. Understanding AM process parameters (implemented by program algorithms called slicers) is necessary to predict part behavior. Investigating algorithms controlling print parameters (slicers) revealed stark differences between the generation of part layers. In this work, tensile testing experiments, including a full factorial design, determined that three key factors, width, thickness, infill density, and their interactions, significantly affect the tensile properties of 3D printed test samples.

Boosting beauty in an economic decline: mating, spending, and the lipstick effect.

PubMed

Hill, Sarah E; Rodeheffer, Christopher D; Griskevicius, Vladas; Durante, Kristina; White, Andrew Edward

2012-08-01

Although consumer spending typically declines in economic recessions, some observers have noted that recessions appear to increase women's spending on beauty products--the so-called lipstick effect. Using both historical spending data and rigorous experiments, the authors examine how and why economic recessions influence women's consumer behavior. Findings revealed that recessionary cues--whether naturally occurring or experimentally primed--decreased desire for most products (e.g., electronics, household items). However, these cues consistently increased women's desire for products that increase attractiveness to mates--the first experimental demonstration of the lipstick effect. Additional studies show that this effect is driven by women's desire to attract mates with resources and depends on the perceived mate attraction function served by these products. In addition to showing how and why economic recessions influence women's desire for beauty products, this research provides novel insights into women's mating psychology, consumer behavior, and the relationship between the two.

Flow regimes in a shallow rotating cylindrical annulus with temperature gradients imposed on the horizontal boundaries

NASA Technical Reports Server (NTRS)

Hathaway, D. H.; Fowlis, W. W.

1986-01-01

Experimental flow regime diagrams are determined for a new rotating cylindrical annulus configuration which permits a measure of control over the internal vertical temperature gradient. The new annulus has radial temperature gradients imposed on plane horizontal thermally conducting endwalls (with the cylindrical sidewalls as insulators) and is considered to be more relevant to atmospheric dynamics studies than the classical cylindrical annulus. Observations have revealed that, in addition to the axisymmetric flow and nonaxisymmetric baroclinic wave flow which occur in the classical annulus, two additional nonaxisymmetric flow types occur in the new annulus: boundary-layer thermal convection and deep thermal convection. Flow regime diagrams for three different values of the imposed vertical temperature difference are presented, and explanations for the flow transitions are offered. The new annulus provides scientific backup for the proposed Atmospheric General Circulation Experiment for Spacelab. The apparatus diagram is included.

Can scribes boost FPs' efficiency and job satisfaction?

PubMed

Earls, Stephen T; Savageau, Judith A; Begley, Susan; Saver, Barry G; Sullivan, Kate; Chuman, Alan

2017-04-01

Research in other medical specialties has shown that the addition of medical scribes to the clinical team enhances physicians' practice experience and increases productivity. To date, literature on the implementation of scribes in primary care is limited. To determine the feasibility and benefits of implementing scribes in family medicine, we undertook a pilot mixed- method quality improvement (QI) study. In 2014, we incorporated 4 parttime scribes into an academic family medicine practice consisting of 7 physicians. We then measured, via survey and time-tracking data, the impact the scribes had on physician office hours and productivity, time spent on documentation, perceptions of work-life balance, and physician and patient satisfaction. Six of the 7 faculty physicians participated. This study demonstrated that the use of scribes in a busy academic primary care practice substantially reduced the amount of time that family physicians spent on charting, improved work-life balance, and had good patient acceptance. Specifically, the physicians spent an average of 5.1 fewer hours/week (hrs/wk) on documentation, while various measures of productivity revealed increases ranging from 9.2% to 28.8%. Perhaps most important of all, when the results of the pilot study were annualized, they were projected to generate $168,600 per year--more than twice the $79,500 annual cost of 2 full-time equivalent scribes. Surveys assessing work-life balance demonstrated improvement in the physicians' perception of the administrative burden/paperwork related to practice and a decrease in their perception of the extent to which work encroached on their personal lives. In addition, survey data from 313 patients at the time of their ambulatory visit with a scribe present revealed a high level of comfort. Likewise, surveys completed by physicians after 55 clinical sessions (ie, blocks of consecutive, uninterrupted patient appointments; there are usually 2 sessions per day) revealed good to excellent ratings more than 90% of the time. In an outpatient family medicine clinic, the use of scribes substantially improved physicians' efficiency, job satisfaction, and productivity without negatively impacting the patient experience.

Rapid Solidification in Bulk Ti-Nb Alloys by Single-Track Laser Melting

NASA Astrophysics Data System (ADS)

Roehling, John D.; Perron, Aurélien; Fattebert, Jean-Luc; Haxhimali, Tomorr; Guss, Gabe; Li, Tian T.; Bober, David; Stokes, Adam W.; Clarke, Amy J.; Turchi, Patrice E. A.; Matthews, Manyalibo J.; McKeown, Joseph T.

2018-05-01

Single-track laser melting experiments were performed on bulk Ti-Nb alloys to explore process parameters and the resultant macroscopic structure and microstructure. The microstructures in Ti-20Nb and Ti-50Nb (at.%) alloys exhibited cellular growth during rapid solidification, with average cell size of approximately 0.5 µm. Solidification velocities during cellular growth were calculated from images of melt tracks. Measurements of the composition in the cellular and intercellular regions revealed nonequilibrium partitioning and its dependence on velocity during rapid solidification. Experimental results were used to benchmark a phase-field model to describe rapid solidification under conditions relevant to additive manufacturing.

[Perspectives of psychological aging research].

PubMed

Wahl, H-W; Diegelmann, M

2015-12-01

Psychological aging research (PAF) focuses on age-related changes and behavioral stability (e.g. structure of social relations), performance and competences (e.g. cognitive functioning) as well as experiences (e.g. well-being) in advanced age. Knowledge is based in particular on currently available longitudinal studies, which historically for the first time allow very long observational periods (nearly across the complete life span). Additionally, innovative statistical analytical methods co-developed in the PAF nowadays allow a better understanding of the dynamics of change than ever before. This results in a new picture of psychological aging that confirms the multifaceted strengths of human aging but also reveals new risks of the current "prolonged aging".

Misremembrance of options past: source monitoring and choice.

PubMed

Mather, M; Shafir, E; Johnson, M K

2000-03-01

This study reveals that when remembering past decisions, people engage in choice-supportive memory distortion. When asked to make memory attributions of options' features, participants made source-monitoring errors that supported their decisions. They tended to attribute, both correctly and incorrectly, more positive features to the option they had selected than to its competitor. In addition, they sometimes attributed, both correctly and incorrectly, more negative features to the nonselected option. This pattern of distortion may be beneficial to people's general well-being, reducing regret for options not taken. At the same time, it is problematic for memory accuracy, for accountability, and for learning from past experience.

Identification of sequence motifs in oligonucleotides whose presence is correlated with antisense activity

PubMed Central

Matveeva, O. V.; Tsodikov, A. D.; Giddings, M.; Freier, S. M.; Wyatt, J. R.; Spiridonov, A. N.; Shabalina, S. A.; Gesteland, R. F.; Atkins, J. F.

2000-01-01

Design of antisense oligonucleotides targeting any mRNA can be much more efficient when several activity-enhancing motifs are included and activity-decreasing motifs are avoided. This conclusion was made after statistical analysis of data collected from >1000 experiments with phosphorothioate-modified oligonucleotides. Highly significant positive correlation between the presence of motifs CCAC, TCCC, ACTC, GCCA and CTCT in the oligonucleotide and its antisense efficiency was demonstrated. In addition, negative correlation was revealed for the motifs GGGG, ACTG, AAA and TAA. It was found that the likelihood of activity of an oligonucleotide against a desired mRNA target is sequence motif content dependent. PMID:10908347

Defect-engineered graphene chemical sensors with ultrahigh sensitivity.

PubMed

Lee, Geonyeop; Yang, Gwangseok; Cho, Ara; Han, Jeong Woo; Kim, Jihyun

2016-05-25

We report defect-engineered graphene chemical sensors with ultrahigh sensitivity (e.g., 33% improvement in NO2 sensing and 614% improvement in NH3 sensing). A conventional reactive ion etching system was used to introduce the defects in a controlled manner. The sensitivity of graphene-based chemical sensors increased with increasing defect density until the vacancy-dominant region was reached. In addition, the mechanism of gas sensing was systematically investigated via experiments and density functional theory calculations, which indicated that the vacancy defect is a major contributing factor to the enhanced sensitivity. This study revealed that defect engineering in graphene has significant potential for fabricating ultra-sensitive graphene chemical sensors.

The effectiveness of using computer simulated experiments on junior high students' understanding of the volume displacement concept

NASA Astrophysics Data System (ADS)

Choi, Byung-Soon; Gennaro, Eugene

Several researchers have suggested that the computer holds much promise as a tool for science teachers for use in their classrooms (Bork, 1979, Lunetta & Hofstein, 1981). It also has been said that there needs to be more research in determining the effectiveness of computer software (Tinker, 1983).This study compared the effectiveness of microcomputer simulated experiences with that of parallel instruction involving hands-on laboratory experiences for teaching the concept of volume displacement to junior high school students. This study also assessed the differential effect on students' understanding of the volume displacement concept using sex of the students as another independent variable. In addition, it compared the degree of retention, after 45 days, of both treatment groups.It was found that computer simulated experiences were as effective as hands-on laboratory experiences, and that males, having had hands-on laboratory experiences, performed better on the posttest than females having had the hands-on laboratory experiences. There were no significant differences in performance when comparing males with females using the computer simulation in the learning of the displacement concept. This study also showed that there were no significant differences in the retention levels when the retention scores of the computer simulation groups were compared to those that had the hands-on laboratory experiences. However, an ANOVA of the retention test scores revealed that males in both treatment conditions retained knowledge of volume displacement better than females.

Genome-wide analysis on Chlamydomonas reinhardtii reveals the impact of hydrogen peroxide on protein stress responses and overlap with other stress transcriptomes

DOE PAGES

Blaby, Ian K.; Blaby-Haas, Crysten E.; Pérez-Pérez, María Esther; ...

2015-12-07

Reactive oxygen species (ROS) are produced by and have the potential to be damaging to all aerobic organisms. In photosynthetic organisms, they are an unavoidable byproduct of electron transfer in both the chloroplast and mitochondrion. Here, in this paper, we employ the reference unicellular green alga Chlamydomonas reinhardtii to identify the effect of H 2O 2 on gene expression by monitoring the changes in the transcriptome in a time-course experiment. Comparison of transcriptomes from cells sampled immediately prior to the addition of H 2O 2 and 0.5 and 1 h subsequently revealed 1278 differentially abundant transcripts. Of those transcripts thatmore » increase in abundance, many encode proteins involved in ROS detoxification, protein degradation and stress responses, whereas among those that decrease are transcripts encoding proteins involved in photosynthesis and central carbon metabolism. In addition to these transcriptomic adjustments, we observe that addition of H 2O 2 is followed by an accumulation and oxidation of the total intracellular glutathione pool, and a decrease in photosynthetic O 2 output. Additionally, we analyze our transcriptomes in the context of changes in transcript abundance in response to singlet O 2 (O 2 *), and relate our H 2O 2-induced transcripts to a diurnal transcriptome, where we demonstrate enrichments of H 2O 2-induced transcripts early in the light phase, late in the light phase and 2 h prior to light. In conclusion, on this basis several genes that are highlighted in this work may be involved in previously undiscovered stress remediation pathways or acclimation responses.« less

Differential Growth Response of Colony-Forming α- and γ-Proteobacteria in Dilution Culture and Nutrient Addition Experiments from Lake Kinneret (Israel), the Eastern Mediterranean Sea, and the Gulf of Eilat†

PubMed Central

Pinhassi, Jarone; Berman, Tom

2003-01-01

Even though it is widely accepted that bacterioplankton growth in lakes and marine ecosystems is determined by the trophic status of the systems, knowledge of the relationship between nutrient concentrations and growth of particular bacterial species is almost nonexistent. To address this question, we performed a series of culture experiments with water from Lake Kinneret (Israel), the eastern Mediterranean Sea, and the Gulf of Eilat (northern Red Sea). In the initial water samples, the proportion of CFU was typically <0.002% of the 4′,6′-diamidino-2-phenylindole (DAPI) counts. During incubation until the early stationary phase, the proportion of CFU increased to 20% of the DAPI counts and to 2 to 15% of the DAPI counts in unenriched lake water and seawater dilution cultures, respectively. Sequencing of the 16S ribosomal DNA of colony-forming bacteria in these cultures consistently revealed an abundance of α-proteobacteria, but notable phylogenetic differences were found at the genus level. Marine dilution cultures were dominated by bacteria in the Roseobacter clade, while lake dilution cultures were dominated by bacteria affiliated with the genera Sphingomonas and Caulobacter. In nutrient (glucose, ammonium, phosphate) addition experiments the CFU comprised 20 to 83% of the newly grown cells. In these incubation experiments fast-growing γ-proteobacteria dominated; in the marine experiments primarily different Vibrio and Alteromonas species appeared, while in the lake water experiments species of the genera Shewanella, Aeromonas, and Rheinheimera grew. These results suggest that major, but different, γ-proteobacterial genera in both freshwater and marine environments have a preference for elevated concentrations of nutrients and easily assimilated organic carbon sources but are selectively outcompeted by α-proteobacteria in the presence of low nutrient concentrations. PMID:12513996

Effect of fenofibrate on oxidative DNA damage and on gene expression related to cell proliferation and apoptosis in rats.

PubMed

Nishimura, Jihei; Dewa, Yasuaki; Muguruma, Masako; Kuroiwa, Yuichi; Yasuno, Hiroaki; Shima, Tomomi; Jin, Mailan; Takahashi, Miwa; Umemura, Takashi; Mitsumori, Kunitoshi

2007-05-01

To investigate the relationship between fenofibrate (FF) and oxidative stress, enzymatic, histopathological, and molecular biological analyses were performed in the liver of male F344 rats fed 2 doses of FF (Experiment 1; 0 and 6000 ppm) for 3 weeks and 3 doses (Experiment 2; 0, 3000, and 6000 ppm) for 9 weeks. FF treatment increased the activity of enzymes such as carnitine acetyltransferase, carnitine palmitoyltransferase, fatty acyl-CoA oxidizing system, and catalase in the liver. However, it decreased those of superoxide dismutase in the liver in both experiments. Increased 8-hydroxy-2'-deoxyguanosine levels in liver DNA and lipofuscin accumulation were observed in the treated rats of Experiment 2. In vitro measurement of reactive oxygen species (ROS) in rat liver microsomes revealed a dose-dependent increase due to FF treatment. Microarray (only Experiment 1) or real-time reverse transcription-polymerase chain reaction analyses revealed that the expression levels of metabolism and DNA repair-related genes such as Aco, Cyp4a1, Cat, Yc2, Gpx2, Apex1, Xrcc5, Mgmt, Mlh1, Gadd45a, and Nbn were increased in FF-treated rats. These results provide evidence of a direct or indirect relationship between oxidative stress and FF treatment. In addition, increases in the expression levels of cell cycle-related genes such as Chek1, Cdc25a, and Ccdn1; increases in the expression levels of cell proliferation-related genes such as Hdgfrp3 and Vegfb; and fluctuations in the expression levels of apoptosis-related genes such as Casp11 and Trp53inp1 were observed in these rats. This suggests that cell proliferation induction, apoptosis suppression, and DNA damage due to oxidative stresses are probably involved in the mechanism of hepatocarcinogenesis due to FF in rats.

Using SEM Analysis on Ion-Milled Shale Surface to Determine Shale-Fracturing Fluid Interaction

NASA Astrophysics Data System (ADS)

Lu, J.; Mickler, P. J.; Nicot, J. P.

2014-12-01

It is important to document and assess shale-fluid interaction during hydraulic fracturing (HF) in order to understand its impact on flowback water chemistry and rock property. A series of autoclave experiments were conducted to react shale samples from major oil and gas shales with synthetic HF containing various additives. To better determine mineral dissolution and precipitation at the rock-fluid interface, ion-milling technique was applied to create extremely flat rock surfaces that were examined before and after the autoclave experiments using a scanning electron microscope (SEM) coupled with energy dispersive spectroscopy (EDS) detectors. This method is able to reveal a level of detail not observable on broken surface or mechanically polished surface. It allows direct comparison of the same mineral and organic matter particles before and after the reaction experiments. Minerals undergone dissolution and newly precipitated materials are readily determined by comparing to the exact locations before reaction. The dissolution porosity and the thickness of precipitates can be quantified by tracing and measuring the geometry of the pores and precipitates. Changes in porosity and permeability were confirmed by mercury intrusion capillary tests.

Effects of pH on nano-bubble stability and transport in saturated porous media

NASA Astrophysics Data System (ADS)

Hamamoto, Shoichiro; Takemura, Takato; Suzuki, Kenichiro; Nishimura, Taku

2018-01-01

An understanding of nano-scale bubble (NB) transport in porous media is important for potential application of NBs in soil/groundwater remediation. It is expected that the solution chemistry of NB water highly influences the surface characteristics of NBs and porous media and the interaction between them, thus affecting the stability and transport characteristics of NB. In this study, in addition to stability experiments, one-dimensional column transport experiments using glass beads were conducted to investigate the effects of pH on the NB transport behavior. The results showed that the NBs were more stable under higher pH. Column transport experiments revealed that entrapment of NBs, especially larger ones, was enhanced in lower-pH water, likely suggesting pH-dependent NB attachment and physical straining, both of which are also probably influenced by bubble size. Although relatively smaller NBs were released after switching the eluting fluid to one with lower ionic strength, most of the NBs in lower-pH water were still retained in the porous media even altering the chemical condition.

Role of subsurface ocean in decadal climate predictability over the South Atlantic.

PubMed

Morioka, Yushi; Doi, Takeshi; Storto, Andrea; Masina, Simona; Behera, Swadhin K

2018-06-04

Decadal climate predictability in the South Atlantic is explored by performing reforecast experiments using a coupled general circulation model with two initialization schemes; one is assimilated with observed sea surface temperature (SST) only, and the other is additionally assimilated with observed subsurface ocean temperature and salinity. The South Atlantic is known to undergo decadal variability exhibiting a meridional dipole of SST anomalies through variations in the subtropical high and ocean heat transport. Decadal reforecast experiments in which only the model SST is initialized with the observation do not predict well the observed decadal SST variability in the South Atlantic, while the other experiments in which the model SST and subsurface ocean are initialized with the observation skillfully predict the observed decadal SST variability, particularly in the Southeast Atlantic. In-depth analysis of upper-ocean heat content reveals that a significant improvement of zonal heat transport in the Southeast Atlantic leads to skillful prediction of decadal SST variability there. These results demonstrate potential roles of subsurface ocean assimilation in the skillful prediction of decadal climate variability over the South Atlantic.

Peculiarities of ultrastructure of Chlorella cells growing aboard the Bion-10 during 12 days

NASA Astrophysics Data System (ADS)

Popova, A. F.; Sytnik, K. M.

The ultrastructure of Chlorella cells grown in darkness on a solid agar medium with organic additions aboard the Bion-1O biosatellite was studied. Certain differences in submicroscopic organization of organelles in the experimental cells were revealed compared to the Earth control. The changes are registered mainly in ultrastructure of energetic organelles - mitochondria and plastids of the experimental cells, in particular, an increase of mitochondria and their cristae size, as well as an increase of the total volume of mitochondrion per cell were established. The decrease of the starch amount in the plastid stroma and the electron density of the latter was also observed. In many experimental cells, the increase of condensed chromatin in the nuclei has been noted. Ultrastructural rearrangements in cells after laboratory experiment realized according to the thermogram registered aboard the Bion-10 were insignificant compared to the flight experiment. Data obtained are compared to results of space flight experiments carried out aboard the Bion-9 (polycomponent aquatic system) and the orbital station Mir (solid agar medium).

The impact of social and family-related factors on women's stress experience in household and family work.

PubMed

Sperlich, Stefanie; Geyer, Siegfried

2015-03-01

This study explores the contribution of social and family-related factors to women's experience of an effort-reward imbalance (ERI) in household and family work. Using a population-based sample of German mothers (n = 3,129), we performed stepwise logistic regression analysis in order to determine the relative impact of social and family-related factors on ERI. All factors investigated showed a significant association with at least one ERI component. Considering all predictors simultaneously in the multivariate analysis resulted in a decrease in significance of socioeconomic status in explaining the effort-reward ratio while the impact on low reward partly remained significant. In addition, age of youngest child, number of children, lower levels of perceived social support, domestic work inequity and negative work-to-family spillover, irrespective of being half- or full-time employed, revealed to be important in predicting ERI. The experience of ERI in domestic work is influenced by the social and family environment. Particularly among socially disadvantaged mothers, lack of social recognition for household and family work proved to be a relevant source of psychosocial stress.

Effects of pH on nano-bubble stability and transport in saturated porous media.

PubMed

Hamamoto, Shoichiro; Takemura, Takato; Suzuki, Kenichiro; Nishimura, Taku

2018-01-01

An understanding of nano-scale bubble (NB) transport in porous media is important for potential application of NBs in soil/groundwater remediation. It is expected that the solution chemistry of NB water highly influences the surface characteristics of NBs and porous media and the interaction between them, thus affecting the stability and transport characteristics of NB. In this study, in addition to stability experiments, one-dimensional column transport experiments using glass beads were conducted to investigate the effects of pH on the NB transport behavior. The results showed that the NBs were more stable under higher pH. Column transport experiments revealed that entrapment of NBs, especially larger ones, was enhanced in lower-pH water, likely suggesting pH-dependent NB attachment and physical straining, both of which are also probably influenced by bubble size. Although relatively smaller NBs were released after switching the eluting fluid to one with lower ionic strength, most of the NBs in lower-pH water were still retained in the porous media even altering the chemical condition. Copyright © 2017 Elsevier B.V. All rights reserved.

[Physiological analysis of various types of osmotic diuresis].

PubMed

Marina, A S; Kutina, A V; Natochin, Iu V

2011-12-01

Efficacy of drugs reduced proximal reabsorption was compared in experiments with female Wistar rats. Urine flow rate for the 1st h of experiment was enhanced after polyethylene glycol-400 (PEG) and 6% Na2SO4 infusion by over 30-fold, exenatide--40-fold, glycerol--11-fold as compared with the control. The maximal values of Na+ excretion were observed during Na2SO4 and exenatide administration (280 +/- 31 micromol/h vs. 3.2 +/- 0.6 Imol/h/100 g bw). The highest K+ excretion was revealed in experiments with glycerol administration (41 +/- 5 micromol/h vs. 7 +/- 2 micromol/h/100 g bw), Mg2+ --after exenatide injection (5.3 +/- 1.3 micromol/h vs. 0.16 +/- 0.03 micromol/ h/100 g bw). Diuretic effects were additive after combined administration of maximal doses of exenatide and PEG which suggests a different mechanism of action of solutes filtrated (PEG) to the proximal nephron segment and generated due to Na+/HW-exchange inhibition (exenatide). Osmotic diuretics differ by potency, mechanism of diuretic action and selectivity of ion excretion).

Aversive Learning and Trait Aggression Influence Retaliatory Behavior.

PubMed

Molapour, Tanaz; Lindström, Björn; Olsson, Andreas

2016-01-01

In two experiments (n = 35, n = 34), we used a modified fear-conditioning paradigm to investigate the role of aversive learning in retaliatory behavior in social context. Participants first completed an initial aversive learning phase in which the pairing of a neutral conditioned stimulus (CS; i.e., neutral face) with a naturally aversive unconditioned stimulus (US; electric shock) was learned. Then they were given an opportunity to interact (i.e., administer 0-2 shocks) with the same faces again, during a Test phase. In Experiment 2, we used the same paradigm with the addition of online trial-by-trial ratings (e.g., US expectancy and anger) to examine the role of aversive learning, anger, and the learned expectancy of receiving punishment more closely. Our results indicate that learned aversions influenced future retaliation in a social context. In both experiments, participants showed largest skin conductance responses (SCRs) to the faces paired with one or two shocks, demonstrating successful aversive learning. Importantly, participants administered more shocks to the faces paired with the most number of shocks when the opportunity was given during test. Also, our results revealed that aggressive traits (Buss and Perry Aggression scale) were associated with retaliation only toward CSs associated with aversive experiences. These two experiments show that aggressive traits, when paired with aversive learning experiences enhance the likelihood to act anti-socially toward others.

Absorption and Reflection Experiments on High-Mobility 2DEGs in the Regime of Microwave-Induced Resistance Oscillations

NASA Astrophysics Data System (ADS)

Studenikin, S. A.; Potemski, M.; Sachrajda, A. S.; Hilke, M.; Pfeiffer, L. N.; West, K. W.

2005-04-01

We have performed microwave absorption and near-field reflection experiments on a high mobility GaAs/AlGaAs heterostructure for the same conditions for which Microwave-Induced Resistance Oscillations (MIROs) are observed. It is shown that the electrodynamic aspect of the problem is important in these experiments. In the absorption experiments a broad CR line was observed due to a large reflection from the highly conductive electron gas. There were no additional features observed related to absorption at harmonics of the cyclotron resonance. In near-field reflection experiments a very different oscillation pattern was revealed when compared to MIROs. The oscillation pattern observed in the reflection experiments is probably due to plasma effects occurring in a finite-size sample. The whole microscopic picture of MIROs is more complicated than simply a resonant absorption at harmonics of the cyclotron resonance. Nevertheless, the experimental observations are in good agreement with the model by Durst et al. involving the photo-assisted scattering in the presence of a crossed magnetic field and dc bias. The observed damping factor of MIROs may be attributed to a change in the electron mobility as a function of temperature. MIROs may be considered as a light-induced drift effect, a broad class of phenomena associated with a light-induced asymmetry in the velocity distribution function.

Absorption and Reflection Experiments on High-Mobility 2DEGs in the Regime of Microwave-Induced Resistance Oscillations

NASA Astrophysics Data System (ADS)

Studenikin, S. A.; Potemski, M.; Sachrajda, A. S.; Hilke, M.; Pfeiffer, L. N.; West, K. W.

We have performed microwave absorption and near-field reflection experiments on a high mobility GaAs/AlGaAs heterostructure for the same conditions for which Microwave-Induced Resistance Oscillations (MIROs) are observed. It is shown that the electrodynamic aspect of the problem is important in these experiments. In the absorption experiments a broad CR line was observed due to a large reflection from the highly conductive electron gas. There were no additional features observed related to absorption at harmonics of the cyclotron resonance. In near-field reflection experiments a very different oscillation pattern was revealed when compared to MIROs. The oscillation pattern observed in the reflection experiments is probably due to plasma effects occurring in a finite-size sample. The whole microscopic picture of MIROs is more complicated than simply a resonant absorption at harmonics of the cyclotron resonance. Nevertheless, the experimental observations are in good agreement with the model by Durst et al. involving the photo-assisted scattering in the presence of a crossed magnetic field and dc bias. The observed damping factor of MIROs may be attributed to a change in the electron mobility as a function of temperature. MIROs may be considered as a light-induced drift effect, a broad class of phenomena associated with a light-induced asymmetry in the velocity distribution function.

A Qualitative Inquiry of the Lived Experiences of Music Therapists Who Have Survived Cancer Who Are Working with Medical and Hospice Patients

PubMed Central

Lee, Jin Hyung

2016-01-01

Cancer is a debilitating illness that affects more than one in every three Americans at sometime in their life time regardless of their social, cultural, ethnic, religious, or economic status. A few studies in the psychotherapy literature have investigated the impact of cancer on the personal and professional lives of psychotherapists. However, such investigations are yet unknown in medical or music therapy literature. In this descriptive phenomenological study, the researcher interviewed five American music therapists who have survived cancer and also work with patients in medical hospitals or hospice settings. The purpose of this study was to fully describe their lived experience of surviving cancer and examine how the cancer experience affected their clinical work thereafter. The data was analyzed using an open coding method from grounded theory which identified four major themes: (a) personal significance; (b) relational significance; (c) musical significance and (d) professional significance. The descriptions provided by these participants of their cancer experience as patients, survivors, and cancer surviving therapists, have revealed various psychosocial and physical issues encountered, and numerous coping methods they employed, and poignantly explained how their clinical approach evolved and expanded due to the personal experience of cancer. Specific issues in relation to countertransference, self-disclosure, and ways of developing empathic approaches without having such personal experience were discussed in addition to suggestions for future research. PMID:27917147

A Qualitative Inquiry of the Lived Experiences of Music Therapists Who Have Survived Cancer Who Are Working with Medical and Hospice Patients.

PubMed

Lee, Jin Hyung

2016-01-01

Cancer is a debilitating illness that affects more than one in every three Americans at sometime in their life time regardless of their social, cultural, ethnic, religious, or economic status. A few studies in the psychotherapy literature have investigated the impact of cancer on the personal and professional lives of psychotherapists. However, such investigations are yet unknown in medical or music therapy literature. In this descriptive phenomenological study, the researcher interviewed five American music therapists who have survived cancer and also work with patients in medical hospitals or hospice settings. The purpose of this study was to fully describe their lived experience of surviving cancer and examine how the cancer experience affected their clinical work thereafter. The data was analyzed using an open coding method from grounded theory which identified four major themes: (a) personal significance; (b) relational significance; (c) musical significance and (d) professional significance. The descriptions provided by these participants of their cancer experience as patients, survivors, and cancer surviving therapists, have revealed various psychosocial and physical issues encountered, and numerous coping methods they employed, and poignantly explained how their clinical approach evolved and expanded due to the personal experience of cancer. Specific issues in relation to countertransference, self-disclosure, and ways of developing empathic approaches without having such personal experience were discussed in addition to suggestions for future research.

Aversive Learning and Trait Aggression Influence Retaliatory Behavior

PubMed Central

Molapour, Tanaz; Lindström, Björn; Olsson, Andreas

2016-01-01

In two experiments (n = 35, n = 34), we used a modified fear-conditioning paradigm to investigate the role of aversive learning in retaliatory behavior in social context. Participants first completed an initial aversive learning phase in which the pairing of a neutral conditioned stimulus (CS; i.e., neutral face) with a naturally aversive unconditioned stimulus (US; electric shock) was learned. Then they were given an opportunity to interact (i.e., administer 0–2 shocks) with the same faces again, during a Test phase. In Experiment 2, we used the same paradigm with the addition of online trial-by-trial ratings (e.g., US expectancy and anger) to examine the role of aversive learning, anger, and the learned expectancy of receiving punishment more closely. Our results indicate that learned aversions influenced future retaliation in a social context. In both experiments, participants showed largest skin conductance responses (SCRs) to the faces paired with one or two shocks, demonstrating successful aversive learning. Importantly, participants administered more shocks to the faces paired with the most number of shocks when the opportunity was given during test. Also, our results revealed that aggressive traits (Buss and Perry Aggression scale) were associated with retaliation only toward CSs associated with aversive experiences. These two experiments show that aggressive traits, when paired with aversive learning experiences enhance the likelihood to act anti-socially toward others. PMID:27375520

Racial differences in sexual prejudice and its correlates among heterosexual men.

PubMed

Daboin, Irene; Peterson, John L; Parrott, Dominic J

2015-04-01

Previous research has consistently found sexual prejudice to be a predictor of antigay aggression and has also revealed specific correlates and antecedents of sexual prejudice. However, extant literature reveals mixed findings about potential racial group differences in sexual prejudice, and few studies have examined racial differences in the correlates of sexual prejudice. The aims of this descriptive study were to determine whether there are (a) racial group differences in reports of sexual prejudice and (b) racial group differences in previously identified correlates of sexual prejudice. Participants were 195 heterosexual males, ages 18 to 30 (98 Blacks and 97 Whites), recruited from a large metropolitan city in the southeastern United States. Based on cultural differences in the influence of religion and in attitudes about male sexuality, it was hypothesized that Black participants would report higher sexual prejudice than White participants. Additionally, based on cultural differences in racial views on masculinity and in sociocultural experiences of male gender roles, it was hypothesized that Blacks would report greater endorsement of religious fundamentalism and the traditional male role norm of status than Whites. Results confirmed all of the hypothesized racial differences and revealed additional differences, including a differential effect of the traditional male role norm of status on sexual prejudice, which explains, at least in part, the racial differences found in sexual prejudice. These findings may reflect underlying cultural differences between Black and White males and may aid in the development of future efforts to reduce sexual prejudice and consequently antigay aggression toward sexual minorities. (c) 2015 APA, all rights reserved).

Friction and Wear on the Atomic Scale

NASA Astrophysics Data System (ADS)

Gnecco, Enrico; Bennewitz, Roland; Pfeiffer, Oliver; Socoliuc, Anisoara; Meyer, Ernst

Friction has long been the subject of research: the empirical da Vinci-Amontons friction laws have been common knowledge for centuries. Macroscopic experiments performed by the school of Bowden and Tabor revealed that macroscopic friction can be related to the collective action of small asperities. Over the last 15 years, experiments performed with the atomic force microscope have provided new insights into the physics of single asperities sliding over surfaces. This development, together with the results from complementary experiments using surface force apparatus and the quartz microbalance, have led to the new field of nanotribology. At the same time, increasing computing power has permitted the simulation of processes that occur during sliding contact involving several hundreds of atoms. It has become clear that atomic processes cannot be neglected when interpreting nanotribology experiments. Even on well-defined surfaces, experiments have revealed that atomic structure is directly linked to friction force. This chapter will describe friction force microscopy experiments that reveal, more or less directly, atomic processes during sliding contact.

Changes to the Student Loan Experience: Psychological Predictors and Outcomes

ERIC Educational Resources Information Center

Mueller, Thomas

2014-01-01

This study builds on the work of scholars who have explored psychological perceptions of the student loan experience. Survey analysis ("N" = 175) revealed a multidimensional model was developed through factor analysis and testing, which revealed four latent variables: "Duress," "Mandatory," "Financial," and…

The Lamb-shift experiment in Muonic helium

NASA Astrophysics Data System (ADS)

Nebel, T.; Amaro, F. D.; Antognini, A.; Biraben, F.; Cardoso, J. M. R.; Covita, D. S.; Dax, A.; Fernandes, L. M. P.; Gouvea, A. L.; Graf, T.; Hänsch, T. W.; Hildebrandt, M.; Indelicato, P.; Julien, L.; Kirch, K.; Kottmann, F.; Liu, Y.-W.; Monteiro, C. M. B.; Nez, F.; Santos, J. M. F. dos; Schuhmann, K.; Taqqu, D.; Veloso, J. F. C. A.; Voss, A.; Pohl, R.

2012-12-01

We propose to measure several transition frequencies between the 2 S and the 2 P states (Lamb shift) in muonic helium ions ( μ 4He + and μ 3He + ) by means of laser spectroscopy, in order to determine the alpha-particle and helion root-mean-square (rms) charge radius. In addition, the fine and hyperfine structure components will be revealed, and the magnetic moment distribution radius will be determined. The contribution of the finite size effect to the Lamb shift (2 S - 2 P energy difference) in μHe + is as high as 20 %. Therefore a measurement of the transition frequencies with a moderate (for laser spectroscopy) precision of 50 ppm (corresponding to 1/20 of the linewidth) will lead to a determination of the nuclear rms charge radii with a relative accuracy of 3 ×10 - 4 (equivalent to 0.0005 fm). The limiting factor for the extraction of the radii from the Lamb shift measurements is given by the uncertainty of the nuclear polarizability contribution. Combined with an ongoing experiment at MPQ aiming to measure the 1 S - 2 S transition frequency in the helium ion, the Lamb shift measurement in μHe + will lead to a sensitive test of problematic and challenging bound-state QED terms. This measurement will also help to clarify the discrepancy found in our previous μ p experiment. Additionally, a precise knowledge of the absolute nuclear radii of the He isotopes and the hyperfine splitting of μ 3He + provide a relevant test of few-nucleon theories.

The Lamb-shift experiment in Muonic helium

NASA Astrophysics Data System (ADS)

Nebel, T.; Amaro, F. D.; Antognini, A.; Biraben, F.; Cardoso, J. M. R.; Covita, D. S.; Dax, A.; Fernandes, L. M. P.; Gouvea, A. L.; Graf, T.; Hänsch, T. W.; Hildebrandt, M.; Indelicato, P.; Julien, L.; Kirch, K.; Kottmann, F.; Liu, Y.-W.; Monteiro, C. M. B.; Nez, F.; Santos, J. M. F. dos; Schuhmann, K.; Taqqu, D.; Veloso, J. F. C. A.; Voss, A.; Pohl, R.

We propose to measure several transition frequencies between the 2S and the 2P states (Lamb shift) in muonic helium ions (μ 4He + and μ 3He + ) by means of laser spectroscopy, in order to determine the alpha-particle and helion root-mean-square (rms) charge radius. In addition, the fine and hyperfine structure components will be revealed, and the magnetic moment distribution radius will be determined. The contribution of the finite size effect to the Lamb shift (2S - 2P energy difference) in μHe + is as high as 20 %. Therefore a measurement of the transition frequencies with a moderate (for laser spectroscopy) precision of 50 ppm (corresponding to 1/20 of the linewidth) will lead to a determination of the nuclear rms charge radii with a relative accuracy of 3 ×10 - 4 (equivalent to 0.0005 fm). The limiting factor for the extraction of the radii from the Lamb shift measurements is given by the uncertainty of the nuclear polarizability contribution. Combined with an ongoing experiment at MPQ aiming to measure the 1S - 2S transition frequency in the helium ion, the Lamb shift measurement in μHe + will lead to a sensitive test of problematic and challenging bound-state QED terms. This measurement will also help to clarify the discrepancy found in our previous μ p experiment. Additionally, a precise knowledge of the absolute nuclear radii of the He isotopes and the hyperfine splitting of μ 3He + provide a relevant test of few-nucleon theories.

How Visual Is the Visual Cortex? Comparing Connectional and Functional Fingerprints between Congenitally Blind and Sighted Individuals.

PubMed

Wang, Xiaoying; Peelen, Marius V; Han, Zaizhu; He, Chenxi; Caramazza, Alfonso; Bi, Yanchao

2015-09-09

Classical animal visual deprivation studies and human neuroimaging studies have shown that visual experience plays a critical role in shaping the functionality and connectivity of the visual cortex. Interestingly, recent studies have additionally reported circumscribed regions in the visual cortex in which functional selectivity was remarkably similar in individuals with and without visual experience. Here, by directly comparing resting-state and task-based fMRI data in congenitally blind and sighted human subjects, we obtained large-scale continuous maps of the degree to which connectional and functional "fingerprints" of ventral visual cortex depend on visual experience. We found a close agreement between connectional and functional maps, pointing to a strong interdependence of connectivity and function. Visual experience (or the absence thereof) had a pronounced effect on the resting-state connectivity and functional response profile of occipital cortex and the posterior lateral fusiform gyrus. By contrast, connectional and functional fingerprints in the anterior medial and posterior lateral parts of the ventral visual cortex were statistically indistinguishable between blind and sighted individuals. These results provide a large-scale mapping of the influence of visual experience on the development of both functional and connectivity properties of visual cortex, which serves as a basis for the formulation of new hypotheses regarding the functionality and plasticity of specific subregions. Significance statement: How is the functionality and connectivity of the visual cortex shaped by visual experience? By directly comparing resting-state and task-based fMRI data in congenitally blind and sighted subjects, we obtained large-scale continuous maps of the degree to which connectional and functional "fingerprints" of ventral visual cortex depend on visual experience. In addition to revealing regions that are strongly dependent on visual experience (early visual cortex and posterior fusiform gyrus), our results showed regions in which connectional and functional patterns are highly similar in blind and sighted individuals (anterior medial and posterior lateral ventral occipital temporal cortex). These results serve as a basis for the formulation of new hypotheses regarding the functionality and plasticity of specific subregions of the visual cortex. Copyright © 2015 the authors 0270-6474/15/3512545-15$15.00/0.

Tidal pulsing alters nitrous oxide fluxes in a temperate intertidal mudflat.

PubMed

Vieillard, A M; Fulweiler, R W

2014-07-01

Environmental pulses, or sudden, marked changes to the conditions within an ecosystem, can be important drivers of resource availability in many systems. In this study, we investigated the effect of tidal pulsing on the fluxes of nitrous oxide (N2O), a powerful greenhouse gas, from a marine intertidal mudflat on the north shore of Massachusetts, USA. We found these tidal flat sediments to be a sink of N2O at low tide with an average uptake rate of -6.7 +/- 2 micromol x m(-2) x h(-1). Further, this N20 sink increased the longer sediments were tidally exposed. These field measurements, in conjunction with laboratory nutrient additions, revealed that this flux appears to be driven primarily by sediment denitrification. Additionally, N2O uptake was most responsive to dissolved inorganic nitrogen with phosphorus (DIN + DIP) addition, suggesting that the N2O consumption process may be P limited. Furthermore, nutrient addition experiments suggest that dissimilatory nitrate reduction to ammonium (DNRA) releases N20 at the highest levels of nitrate fertilization. Our findings indicate that tidal flats are important sinks of N2O, potentially capable of offsetting the release of this potent greenhouse gas by other, nearby ecosystems.

Glycerol as an additional carbon source for bacterial cellulose synthesis

NASA Astrophysics Data System (ADS)

Agustin, Y. E.; Padmawijaya, K. S.; Rixwari, H. F.; Yuniharto, V. A. S.

2018-03-01

Bacterial cellulose, the fermentation result of Acetobacter xylinus can be produced when glycerol was used as an additional carbon source. In this research, bacterial cellulose produced in two different fermentation medium, Hestrin and Scharmm (HS) medium and HS medium with additional MgSO4. Concentration of glycerol that used in this research were 0%; 5%; 10%; and 15% (v/v). The optimum conditions of bacterial cellulose production on each experiment variations determined by characterization of the mechanical properties, including thickness, tensile strength and elongation. Fourier Transform Infra Red Spectroscopy (FTIR) revealed the characterization of bacterial cellulose. Results showed that the growth rate of bacterial cellulose in HS-MgSO4-glycerol medium was faster than in HS-glycerol medium. Increasing concentrations of glycerol will lower the value of tensile strength and elongation. Elongation test showed that the elongation bacterial cellulose (BC) with the addition of 4.95% (v/v) glycerol in the HS-MgSO4 medium is the highest elongation value. The optimum bacterial cellulose production was achieved when 4.95% (v/v) of glycerol added into HS-MgSO4 medium with stress at break of 116.885 MPa and 4.214% elongation.

Seeing through rose-colored glasses: How optimistic expectancies guide visual attention

PubMed Central

Bristle, Mirko; Aue, Tatjana

2018-01-01

Optimism bias and positive attention bias have important highly similar implications for mental health but have only been examined in isolation. Investigating the causal relationships between these biases can improve the understanding of their underlying cognitive mechanisms, leading to new directions in neurocognitive research and revealing important information about normal functioning as well as the development, maintenance, and treatment of psychological diseases. In the current project, we hypothesized that optimistic expectancies can exert causal influences on attention deployment. To test this causal relation, we conducted two experiments in which we manipulated optimistic and pessimistic expectancies regarding future rewards and punishments. In a subsequent visual search task, we examined participants’ attention to positive (i.e., rewarding) and negative (i.e., punishing) target stimuli, measuring their eye gaze behavior and reaction times. In both experiments, participants’ attention was guided toward reward compared with punishment when optimistic expectancies were induced. Additionally, in Experiment 2, participants’ attention was guided toward punishment compared with reward when pessimistic expectancies were induced. However, the effect of optimistic (rather than pessimistic) expectancies on attention deployment was stronger. A key characteristic of optimism bias is that people selectively update expectancies in an optimistic direction, not in a pessimistic direction, when receiving feedback. As revealed in our studies, selective attention to rewarding versus punishing evidence when people are optimistic might explain this updating asymmetry. Thus, the current data can help clarify why optimistic expectancies are difficult to overcome. Our findings elucidate the cognitive mechanisms underlying optimism and attention bias, which can yield a better understanding of their benefits for mental health. PMID:29466420

Seeing through rose-colored glasses: How optimistic expectancies guide visual attention.

PubMed

Kress, Laura; Bristle, Mirko; Aue, Tatjana

2018-01-01

Optimism bias and positive attention bias have important highly similar implications for mental health but have only been examined in isolation. Investigating the causal relationships between these biases can improve the understanding of their underlying cognitive mechanisms, leading to new directions in neurocognitive research and revealing important information about normal functioning as well as the development, maintenance, and treatment of psychological diseases. In the current project, we hypothesized that optimistic expectancies can exert causal influences on attention deployment. To test this causal relation, we conducted two experiments in which we manipulated optimistic and pessimistic expectancies regarding future rewards and punishments. In a subsequent visual search task, we examined participants' attention to positive (i.e., rewarding) and negative (i.e., punishing) target stimuli, measuring their eye gaze behavior and reaction times. In both experiments, participants' attention was guided toward reward compared with punishment when optimistic expectancies were induced. Additionally, in Experiment 2, participants' attention was guided toward punishment compared with reward when pessimistic expectancies were induced. However, the effect of optimistic (rather than pessimistic) expectancies on attention deployment was stronger. A key characteristic of optimism bias is that people selectively update expectancies in an optimistic direction, not in a pessimistic direction, when receiving feedback. As revealed in our studies, selective attention to rewarding versus punishing evidence when people are optimistic might explain this updating asymmetry. Thus, the current data can help clarify why optimistic expectancies are difficult to overcome. Our findings elucidate the cognitive mechanisms underlying optimism and attention bias, which can yield a better understanding of their benefits for mental health.

Arsenic metabolism by microbial communities from an arsenic-rich shallow-water hydrothermal system in Ambitle Island, Papua New Guinea

NASA Astrophysics Data System (ADS)

Ruiz Chancho, M.; Pichler, T.; Amend, J. P.; Akerman, N. H.

2011-12-01

Arsenic, although toxic, is used as an energy source by certain microbes, some of which can catalyse the reduction of arsenate by using different electron donors, while others oxidize arsenite with oxygen or nitrate as electron acceptors. The marine shallow-water hydrothermal system in Tutum Bay, Ambitle Island, Papua New Guinea is ideal for investigating the metabolism of microbes involved in arsenic cycling, because there hydrothermal vents discharge fluids with arsenite concentrations as high as 950 μg/L. Vent fluids are hot (˜100°C), slightly acidic (pH˜6) and reducing. Upon mixing with colder and oxygen-rich seawater the fluid chemistry changes rapidly within a few meters from the hydrothermal source. The objective of this work was to study arsenic metabolism due to microbial activity in Tutum Bay. Sediments collected at 7.5 and 30 m along a transect beginning at a hydrothermal vent were used as inocula in the microbial culturing experiments. Media were designed using chemical analyses of the hydrothermal fluids. Following culture experiments, arsenic species identification and quantification were performed for the growth media with HPLC-ICP(HR)MS, using anion exchange and reversed phase chromatography. Quality control included mass balance calculations and spiking experiments. A fast reduction of arsenate to arsenite was observed in the first 24 hours leading to the conclusion that the microbial communities were capable of reducing arsenic. However, mass balance calculations revealed that more than 30% of the arsenic had been transformed to one or more unknown species, which could not be detected by ion exchange chromatography. The addition of peroxide combined with reversed phase chromatography revealed the presence of several unknown species. Following the addition of peroxide some of the unknown species were identified to be thio-arsenic compounds, because they were oxidized to their oxo-analogues. Nevertheless, a significant fraction of unknown arsenic species could not be identified and remain to be studied further with the help of molecular mass spectrometric techniques. At this time it can be concluded that the metabolic processes involving arsenic in Tutum Bay's microbial communities are complex but that arsenic definitely plays an important role.

Small-mammal seed predation limits the recruitment and abundance of two perennial grassland forbs.

PubMed

Bricker, Mary; Pearson, Dean; Maron, John

2010-01-01

Although post-dispersal seed predators are common and often reduce seed density, their influence on plant population abundance remains unclear. On the one hand, increasing evidence suggests that many plant populations are seed limited, implying that seed predators could reduce plant abundance. On the other hand,.it is generally uncertain whether the magnitude of seed limitation imposed by granivores is strong enough to overcome density-dependent processes that could compensate for seed loss at later stages. We examined the impact of seed predation by small mammals, primarily deer mice (Peromyscus maniculatus), on seedling recruitment and subsequent plant establishment of two perennial grassland forbs in western Montana, USA: Lupinus sericeus (Fabaceae) and Lithospermum ruderale (Boraginaceae). The experiment combined graded densities of seed addition for each species with a small-mammal exclusion treatment. Seedling recruitment and plant establishment were monitored in the experimental plots for up to three years. For both species, small-mammal exclusion increased the total number of seedlings that emerged, and these effects were still significant three years after seed addition, resulting in greater numbers of established plants inside exclosures than in control plots. We also found evidence of seed limitation, with increasing density of seeds added leading to increased numbers of seedlings. Results from seed addition and small-mammal exclusion experiments in later years also revealed significant impacts of small mammals on seedling emergence. These results suggest that granivores can have potentially important impacts in limiting forb abundance in grasslands communities.

pH-independent immediate release polymethacrylate formulations--an observational study.

PubMed

Claeys, Bart; Vandeputte, Reinout; De Geest, Bruno G; Remon, Jean Paul; Vervaet, Chris

2016-01-01

Using Eudragit® E PO (EudrE) as a polymethacrylate carrier, the aim of the study was to develop a pH-independent dosage form containing ibuprofen (IBP) as an active compound via chemical modification of the polymer (i.e. quaternization of amine function) or via the addition of dicarboxylic acids (succinic, glutaric and adipic acid) to create a pH micro-environment during dissolution. Biconvex tablets (diameter: 10 mm; height: 5 mm) were produced via hot melt extrusion and injection molding. In vitro dissolution experiments revealed that a minimum of 25% of quaternization was sufficient to partially (up to pH 5) eliminate the pH-dependent effect of the EudrE/IBP formulation. The addition of dicarboxylic acids did not alter IBP release in a pH 1 and 3 medium as the dimethyl amino groups of EudrE are already fully protonated, while in a pH 5 solvent IBP release was significantly improved (cf. from 0% to 92% release after 1 h dissolution experiments upon the addition of 20 wt.% succinic acid). Hence, both approaches resulted in a pH-independent (up to pH 5) immediate release formulation. However, the presence of a positively charged polymer induced stability issues (recrystallization of API) and the formulations containing dicarboxylic acids were classified as mechanically unstable. Hence, further research is needed to obtain a pH-independent immediate release formulation while using EudrE as a polmethacrylate carrier.

Degradation mechanisms of DDX induced by the addition of toluene and glycerol as cosubstrates in a zero-valent iron pretreated soil.

PubMed

Velasco, Antonio; Aburto-Medina, Arturo; Shahsavari, Esmaeil; Revah, Sergio; Ortiz, Irmene

2017-01-05

Abiotic and biotic processes can be used to remediate DDX (DDT, DDD, DDE, and DDNS) contaminated soils; these processes can be fostered using specific carbon-amendments to stimulate particular soil indigenous microbial communities to improve rates or extent of degradation. In this study, toluene and glycerol were evaluated as cosubstrates under aerobic and anoxic conditions to determine the degradation efficiencies of DDX and to elucidate possible degradation mechanisms. Slurry microcosms experiments were performed during 60 days using pretreated soil with zero-valent iron (ZVI). Toluene addition enhanced the percentage of degradation of DDX. DDNS was the main compound degraded (around 86%) under aerobic conditions, suggesting cometabolic degradation of DDX by toluene-degrading soil bacteria. Glycerol addition under anoxic conditions favored the abiotic degradation of DDX mediated by sulfate-reducing bacteria activity, where DDT was the main compound degraded (around 90%). The 16S rDNA metagenomic analyses revealed Rhodococcus ruber and Desulfosporosinus auripigmenti as the predominant bacterial species after 40 days of treatment with toluene and glycerol additions, respectively. This study provides evidence of biotic and abiotic DDX degradation by the addition of toluene and glycerol as cosubstrates in ZVI pretreated DDX-contaminated soil. Copyright © 2016 Elsevier B.V. All rights reserved.

Seedling growth responses to phosphorus reflect adult distribution patterns of tropical trees.

PubMed

Zalamea, Paul-Camilo; Turner, Benjamin L; Winter, Klaus; Jones, F Andrew; Sarmiento, Carolina; Dalling, James W

2016-10-01

Soils influence tropical forest composition at regional scales. In Panama, data on tree communities and underlying soils indicate that species frequently show distributional associations to soil phosphorus. To understand how these associations arise, we combined a pot experiment to measure seedling responses of 15 pioneer species to phosphorus addition with an analysis of the phylogenetic structure of phosphorus associations of the entire tree community. Growth responses of pioneers to phosphorus addition revealed a clear tradeoff: species from high-phosphorus sites grew fastest in the phosphorus-addition treatment, while species from low-phosphorus sites grew fastest in the low-phosphorus treatment. Traits associated with growth performance remain unclear: biomass allocation, phosphatase activity and phosphorus-use efficiency did not correlate with phosphorus associations; however, phosphatase activity was most strongly down-regulated in response to phosphorus addition in species from high-phosphorus sites. Phylogenetic analysis indicated that pioneers occur more frequently in clades where phosphorus associations are overdispersed as compared with the overall tree community, suggesting that selection on phosphorus acquisition and use may be strongest for pioneer species with high phosphorus demand. Our results show that phosphorus-dependent growth rates provide an additional explanation for the regional distribution of tree species in Panama, and possibly elsewhere. © 2016 The Authors. New Phytologist © 2016 New Phytologist Trust.

Structural and water diffusion of poly(acryl amide)/poly(vinyl alcohol) blend films: Experiment and molecular dynamics simulations.

PubMed

Wang, Yanen; Wei, Qinghua; Wang, Shuzhi; Chai, Weihong; Zhang, Yingfeng

2017-01-01

To study the effects of composition ratios and temperature on the diffusion of water molecules in PVA/PAM blend films, five simulation models of PVA/PAM with ten water molecules at different composition ratios (4/0, 3/1, 2/2, 1/3, 0/4) were constructed and simulated by using a molecular dynamics (MD) simulation. The diffusion behavior of water molecules in blends were investigated from the aspects of the diffusion coefficient, free volume, pair correlation function (PCF) and trajectories of water molecules, respectively. And the hydrophilicity of blend composite was studied based on the contact angle and equilibrium water content (EWC) of the blend films. The simulation results show that the diffusion coefficient of water molecules and fractional free volume (FFV) of blend membranes increase with the addition of PAM, and a higher temperature can also improve the diffusion of water molecules. Additionally, the analysis of PCFs reveals the main reason why the diffusion coefficient of water in blend system increases with the addition of PAM. The measurement results of contact angle and EWC of blend films indicate that the hydrophilicity of blend films decreases with the addition of PAM, but the EWC of blends increases with the addition of PAM. Copyright © 2016 Elsevier Inc. All rights reserved.

How our own speech rate influences our perception of others.

PubMed

Bosker, Hans Rutger

2017-08-01

In conversation, our own speech and that of others follow each other in rapid succession. Effects of the surrounding context on speech perception are well documented but, despite the ubiquity of the sound of our own voice, it is unknown whether our own speech also influences our perception of other talkers. This study investigated context effects induced by our own speech through 6 experiments, specifically targeting rate normalization (i.e., perceiving phonetic segments relative to surrounding speech rate). Experiment 1 revealed that hearing prerecorded fast or slow context sentences altered the perception of ambiguous vowels, replicating earlier work. Experiment 2 demonstrated that talking at a fast or slow rate prior to target presentation also altered target perception, though the effect of preceding speech rate was reduced. Experiment 3 showed that silent talking (i.e., inner speech) at fast or slow rates did not modulate the perception of others, suggesting that the effect of self-produced speech rate in Experiment 2 arose through monitoring of the external speech signal. Experiment 4 demonstrated that, when participants were played back their own (fast/slow) speech, no reduction of the effect of preceding speech rate was observed, suggesting that the additional task of speech production may be responsible for the reduced effect in Experiment 2. Finally, Experiments 5 and 6 replicate Experiments 2 and 3 with new participant samples. Taken together, these results suggest that variation in speech production may induce variation in speech perception, thus carrying implications for our understanding of spoken communication in dialogue settings. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Encouraging top-down attention in visual search:A developmental perspective.

PubMed

Lookadoo, Regan; Yang, Yingying; Merrill, Edward C

2017-10-01

Four experiments are reported in which 60 younger children (7-8 years old), 60 older children (10-11 years old), and 60 young adults (18-25 years old) performed a conjunctive visual search task (15 per group in each experiment). The number of distractors of each feature type was unbalanced across displays to evaluate participants' ability to restrict search to the smaller subset of features. The use of top-down attention processes to restrict search was encouraged by providing external aids for identifying and maintaining attention on the smaller set. In Experiment 1, no external assistance was provided. In Experiment 2, precues and instructions were provided to focus attention on that subset. In Experiment 3, trials in which the smaller subset was represented by the same feature were presented in alternating blocks to eliminate the need to switch attention between features from trial to trial. In Experiment 4, consecutive blocks of the same subset features were presented in the first or second half of the experiment, providing additional consistency. All groups benefited from external support of top-down attention, although the pattern of improvement varied across experiments. The younger children benefited most from precues and instruction, using the subset search strategy when instructed. Furthermore, younger children benefited from blocking trials only when blocks of the same features did not alternate. Older participants benefited from the blocking of trials in both Experiments 3 and 4, but not from precues and instructions. Hence, our results revealed both malleability and limits of children's top-down control of attention.

Adaptation to High Ethanol Reveals Complex Evolutionary Pathways

PubMed Central

Das, Anupam; Espinosa-Cantú, Adriana; De Maeyer, Dries; Arslan, Ahmed; Van Pee, Michiel; van der Zande, Elisa; Meert, Wim; Yang, Yudi; Zhu, Bo; Marchal, Kathleen; DeLuna, Alexander; Van Noort, Vera; Jelier, Rob; Verstrepen, Kevin J.

2015-01-01

Tolerance to high levels of ethanol is an ecologically and industrially relevant phenotype of microbes, but the molecular mechanisms underlying this complex trait remain largely unknown. Here, we use long-term experimental evolution of isogenic yeast populations of different initial ploidy to study adaptation to increasing levels of ethanol. Whole-genome sequencing of more than 30 evolved populations and over 100 adapted clones isolated throughout this two-year evolution experiment revealed how a complex interplay of de novo single nucleotide mutations, copy number variation, ploidy changes, mutator phenotypes, and clonal interference led to a significant increase in ethanol tolerance. Although the specific mutations differ between different evolved lineages, application of a novel computational pipeline, PheNetic, revealed that many mutations target functional modules involved in stress response, cell cycle regulation, DNA repair and respiration. Measuring the fitness effects of selected mutations introduced in non-evolved ethanol-sensitive cells revealed several adaptive mutations that had previously not been implicated in ethanol tolerance, including mutations in PRT1, VPS70 and MEX67. Interestingly, variation in VPS70 was recently identified as a QTL for ethanol tolerance in an industrial bio-ethanol strain. Taken together, our results show how, in contrast to adaptation to some other stresses, adaptation to a continuous complex and severe stress involves interplay of different evolutionary mechanisms. In addition, our study reveals functional modules involved in ethanol resistance and identifies several mutations that could help to improve the ethanol tolerance of industrial yeasts. PMID:26545090

Physiotherapy students' experiences of bullying on clinical internships: a qualitative study.

PubMed

Whiteside, Diana; Stubbs, Brendon; Soundy, Andy

2014-03-01

To consider the experiences of final-year physiotherapy students who have experienced workplace bullying on a clinical internship. Qualitative methodology using individual semi-structured interviews. A university in the Midlands region of the UK. Eight undergraduate physiotherapy students who had experienced one incident of bullying on a clinical internship. Thematic analysis of semi-structured interviews. Four main themes were identified: (1) external and situational influences of bullying; (2) students' reactions to the experience of bullying; (3) inability to reveal the experience; and (4) overcoming problems. Bullying had a range of adverse effects on the students, with many expressing self-doubt in their competence and viewing their supervisor as unapproachable and unsupportive. Five students were not initially able to recognise the experience as bullying. In addition, students did not feel able to report the experience and use the support mechanisms in place. This may have been a result of having concerns that the problem would escalate if they reported the experience and, as a consequence, have a negative effect on their grade. Students were keen to offer a range of strategies for clinical practice in order to prevent bullying for future generations of students. Students' health, security and confidence in their ability as a physiotherapist can be at great risk from bullying. Steps are needed to ensure that students are better protected from bullying, and feel more able to address bullying behaviour during clinical internships. Copyright © 2013 Chartered Society of Physiotherapy. Published by Elsevier Ltd. All rights reserved.

Observer age and the social transmission of attractiveness in humans: Younger women are more influenced by the choices of popular others than older women.

PubMed

Little, Anthony C; Caldwell, Christine A; Jones, Benedict C; DeBruine, Lisa M

2015-08-01

Being paired with an attractive partner increases perceptual judgements of attractiveness in humans. We tested experimentally for prestige bias, whereby individuals follow the choices of prestigious others. Women rated the attractiveness of photographs of target males which were paired with either popular or less popular model female partners. We found that pairing a photo of a man with a woman presented as his partner positively influenced the attractiveness of the man when the woman was presented as more popular (Experiment 1). Further, this effect was stronger in younger participants compared to older participants (Experiment 1). Reversing the target and model such that women were asked to rate women paired with popular and less popular men revealed no effect of model popularity and this effect was unrelated to participant age (Experiment 2). An additional experiment confirmed that participant age and not stimulus age primarily influenced the tendency to follow others' preferences in Experiment 1 (Experiment 3). We also confirmed that our manipulations of popularity lead to variation in rated prestige (Experiment 4). These results suggest a sophisticated model-based bias in social learning whereby individuals are most influenced by the choices of those who have high popularity/prestige. Furthermore, older individuals moderate their use of such social information and so this form of social learning appears strongest in younger women. © 2014 The British Psychological Society.

Revealing the Earth's mantle from the tallest mountains using the Jinping Neutrino Experiment.

PubMed

Šrámek, Ondřej; Roskovec, Bedřich; Wipperfurth, Scott A; Xi, Yufei; McDonough, William F

2016-09-09

The Earth's engine is driven by unknown proportions of primordial energy and heat produced in radioactive decay. Unfortunately, competing models of Earth's composition reveal an order of magnitude uncertainty in the amount of radiogenic power driving mantle dynamics. Recent measurements of the Earth's flux of geoneutrinos, electron antineutrinos from terrestrial natural radioactivity, reveal the amount of uranium and thorium in the Earth and set limits on the residual proportion of primordial energy. Comparison of the flux measured at large underground neutrino experiments with geologically informed predictions of geoneutrino emission from the crust provide the critical test needed to define the mantle's radiogenic power. Measurement at an oceanic location, distant from nuclear reactors and continental crust, would best reveal the mantle flux, however, no such experiment is anticipated. We predict the geoneutrino flux at the site of the Jinping Neutrino Experiment (Sichuan, China). Within 8 years, the combination of existing data and measurements from soon to come experiments, including Jinping, will exclude end-member models at the 1σ level, define the mantle's radiogenic contribution to the surface heat loss, set limits on the composition of the silicate Earth, and provide significant parameter bounds for models defining the mode of mantle convection.

Green algal over cyanobacterial dominance promoted with nitrogen and phosphorus additions in a mesocosm study at Lake Taihu, China.

PubMed

Ma, Jianrong; Qin, Boqiang; Paerl, Hans W; Brookes, Justin D; Wu, Pan; Zhou, Jian; Deng, Jianming; Guo, Jinsong; Li, Zhe

2015-04-01

Enrichment of waterways with nitrogen (N) and phosphorus (P) has accelerated eutrophication and promoted cyanobacterial blooms worldwide. An understanding of whether cyanobacteria maintain their dominance under accelerated eutrophication will help predict trends and provide rational control measures. A mesocosm experiment was conducted under natural light and temperature conditions in Lake Taihu, China. It revealed that only N added to lake water promoted growth of colonial and filamentous cyanobacteria (Microcystis, Pseudoanabaena and Planktothrix) and single-cell green algae (Cosmarium, Chlorella, and Scenedesmus). Adding P alone promoted neither cyanobacteria nor green algae significantly. N plus P additions promoted cyanobacteria and green algae growth greatly. The higher growth rates of green algae vs. cyanobacteria in N plus P additions resulted in the biomass of green algae exceeding that of cyanobacteria. This indicates that further enrichment with N plus P in eutrophic water will enhance green algae over cyanobacterial dominance. However, it does not mean that eutrophication problems will cease. On the contrary, the risk will increase due to increasing total phytoplankton biomass.

Organics, Isotopes, and Volatiles in Gale Crater Sedimentary Rocks

NASA Astrophysics Data System (ADS)

Mahaffy, P. R.

2016-12-01

Solid samples analyzed by the Curiosity rover on the long traverse from the Gale crater floor to the flanks of Mt. Sharp spread a range of environments from fluvial to lacustrine to eolian, and span 100 m of stratigraphic thickness. The diverse chemical and isotopic composition of organic compounds and inorganic volatiles revealed in these samples analyzed over a period of more than 2 Mars years is described with an emphasis on the search for organics, the chemical environments and physical-chemical processes that respectively preserve or destroy organics, and unexpectedly large variations in H, S, and Cl isotopes. In addition to a set of aromatic and aliphatic chorine containing organic compounds thermally released from the Cumberland mudstone drilled early in the mission compounds [Freissinet et al., 2015], additional S-containing organics have been identified in the Mojave drill sample in the Pahrump Hills section that was characterized in detail over a 5 month period. This set of S and Cl containing compounds is definitively identified by gas chromatograph mass spectrometer (GCMS) analyses. In addition, fragments of other organic compounds are evident in the evolved gas analysis (EGA) experiments implemented by the Sample Analysis at Mars (SAM) instrument and utilization of SAM's derivatization agent has revealed the presence of high molecular weight compounds. Two factors complicate the search for organic compounds preserved from ancient Mars. First the nearly ubiquitous oxychlorine compounds such as perchlorates decompose on heating in the SAM ovens in the EGA experiments and there is evidence that the hot O2 released combusts organic compounds to produce CO2. Secondly, the cosmic radiation that penetrates through the thin Mars atmosphere meters into the surface transforms near surface organic compounds over time. Fortunately, the SAM mass spectrometer can measure spallogenic (3He and 21Ne) and neutron-capture (36Ar) noble gases to secure an estimate of the duration of radiation exposure. Measurement protocols developed to work around both of these limitations will be discussed. C. Freissinet et al, JGR (2015) 120(3), 495-514.

Benchmarking of commercially available CHO cell culture media for antibody production.

PubMed

Reinhart, David; Damjanovic, Lukas; Kaisermayer, Christian; Kunert, Renate

2015-06-01

In this study, eight commercially available, chemically defined Chinese hamster ovary (CHO) cell culture media from different vendors were evaluated in batch culture using an IgG-producing CHO DG44 cell line as a model. Medium adaptation revealed that the occurrence of even small aggregates might be a good indicator of cell growth performance in subsequent high cell density cultures. Batch experiments confirmed that the culture medium has a significant impact on bioprocess performance, but high amino acid concentrations alone were not sufficient to ensure superior cell growth and high antibody production. However, some key amino acids that were limiting in most media could be identified. Unbalanced glucose and amino acids led to high cell-specific lactate and ammonium production rates. In some media, persistently high glucose concentrations probably induced the suppression of respiration and oxidative phosphorylation, known as Crabtree effect, which resulted in high cell-specific glycolysis rates along with a continuous and high lactate production. In additional experiments, two of the eight basal media were supplemented with feeds from two different manufacturers in six combinations, in order to understand the combined impact of media and feeds on cell metabolism in a CHO fed-batch process. Cell growth, nutrient consumption and metabolite production rates, antibody production, and IgG quality were evaluated in detail. Concentrated feed supplements boosted cell concentrations almost threefold and antibody titers up to sevenfold. Depending on the fed-batch strategy, fourfold higher peak cell concentrations and eightfold increased IgG titers (up to 5.8 g/L) were achieved. The glycolytic flux was remarkably similar among the fed-batches; however, substantially different specific lactate production rates were observed in the different media and feed combinations. Further analysis revealed that in addition to the feed additives, the basal medium can make a considerable contribution to the ammonium metabolism of the cells. The glycosylation of the recombinant antibody was influenced by the selection of basal medium and feeds. Differences of up to 50 % in the monogalacto-fucosylated (G1F) and high mannose fraction of the IgG were observed.

Effects of Paternal Predation Risk and Rearing Environment on Maternal Investment and Development of Defensive Responses in the Offspring

PubMed Central

Bauer, Jessica

2016-01-01

Abstract Detecting past experiences with predators of a potential mate informs a female about prevailing ecological threats, in addition to stress-induced phenotypes that may be disseminated to offspring. We examined whether prior exposure of a male rat to a predator (cat) odor influences the attraction of a female toward a male, subsequent mother–infant interactions and the development of defensive (emotional) responses in the offspring. Females displayed less interest in males that had experienced predator odor. Mothers that reared young in larger, seminaturalistic housing provided more licking and grooming and active arched back-nursing behavior toward their offspring compared with dams housed in standard housing, although some effects interacted with paternal experience. Paternal predation risk and maternal rearing environment revealed sex-dependent differences in offspring wean weight, juvenile social interactions, and anxiety-like behavior in adolescence. Additionally, paternal predator experience and maternal housing independently affected variations in crf gene promoter acetylation and crf gene expression in response to an acute stressor in offspring. Our results show for the first time in mammals that variation among males in their predator encounters may contribute to stable behavioral variation among females in preference for mates and maternal care, even when the females are not directly exposed to predator threat. Furthermore, when offspring were exposed to the same threat experienced by the father, hypothalamic crf gene regulation was influenced by paternal olfactory experience and early housing. These results, together with our previous findings, suggest that paternal stress exposure and maternal rearing conditions can influence maternal behavior and the development of defensive responses in offspring. PMID:27896313

Characterization of a linear DNA plasmid from the filamentous fungal plant pathogen Glomerella musae [Anamorph: Colletotrichum musae (Berk. and Curt.) arx.

USGS Publications Warehouse

Freeman, S.; Redman, R.S.; Grantham, G.; Rodriguez, R.J.

1997-01-01

A 7.4-kilobase (kb) DNA plasmid was isolated from Glomerella musae isolate 927 and designated pGML1. Exonuclease treatments indicated that pGML1 was a linear plasmid with blocked 5' termini. Cell-fractionation experiments combined with sequence-specific PCR amplification revealed that pGML1 resided in mitochondria. The pGML1 plasmid hybridized to cesium chloride-fractionated nuclear DNA but not to A + T-rich mitochondrial DNA. An internal 7.0-kb section of pGML1 was cloned and did not hybridize with either nuclear or mitochondrial DNA from G. musae. Sequence analysis revealed identical terminal inverted repeats (TIR) of 520 bp at the ends of the cloned 7.0-kb section of pGML1. The occurrence of pGML1 did not correspond with the pathogenicity of G. musae on banana fruit. Four additional isolates of G. musae possessed extrachromosomal DNA fragments similar in size and sequence to pGML1.

Improvement of the Processes of Liquid-Phase Epitaxial Growth of Nanoheteroepitaxial Structures

NASA Astrophysics Data System (ADS)

Maronchuk, I. I.; Sanikovich, D. D.; Potapkov, P. V.; Vel‧chenko, A. A.

2018-05-01

We have revealed the shortcomings of equipment and technological approaches in growing nanoheteroepitaxial structures with quantum dots by liquid-phase epitaxy. We have developed and fabricated a new vertical barreltype cassette for growing quantum dots and epitaxial layers of various thicknesses in one technological process. A physico-mathematical simulation has been carried out of the processes of liquid-phase epitaxial growth of quantumdimensional structures with the use of the program product SolidWorks (FlowSimulation program). Analysis has revealed the presence of negative factors influencing the growth process of the above structures. The mathematical model has been optimized, and the equipment has been modernized without additional experiments and measurements. The flow dynamics of the process gas in the reactor at various flow rates has been investigated. A method for tuning the thermal equipment has been developed. The calculated and experimental temperature distributions in the process of growing structures with high reproducibility are in good agreement, which confirms the validity of the modernization made.

Cross-hemispheric dopamine projections have functional significance

PubMed Central

Fox, Megan E.; Mikhailova, Maria A.; Bass, Caroline E.; Takmakov, Pavel; Gainetdinov, Raul R.; Budygin, Evgeny A.; Wightman, R. Mark

2016-01-01

Dopamine signaling occurs on a subsecond timescale, and its dysregulation is implicated in pathologies ranging from drug addiction to Parkinson’s disease. Anatomic evidence suggests that some dopamine neurons have cross-hemispheric projections, but the significance of these projections is unknown. Here we report unprecedented interhemispheric communication in the midbrain dopamine system of awake and anesthetized rats. In the anesthetized rats, optogenetic and electrical stimulation of dopamine cells elicited physiologically relevant dopamine release in the contralateral striatum. Contralateral release differed between the dorsal and ventral striatum owing to differential regulation by D2-like receptors. In the freely moving animals, simultaneous bilateral measurements revealed that dopamine release synchronizes between hemispheres and intact, contralateral projections can release dopamine in the midbrain of 6-hydroxydopamine–lesioned rats. These experiments are the first, to our knowledge, to show cross-hemispheric synchronicity in dopamine signaling and support a functional role for contralateral projections. In addition, our data reveal that psychostimulants, such as amphetamine, promote the coupling of dopamine transients between hemispheres. PMID:27298371

The G-protein-coupled receptor, GPR84, is important for eye development in Xenopus laevis.

PubMed

Perry, Kimberly J; Johnson, Verity R; Malloch, Erica L; Fukui, Lisa; Wever, Jason; Thomas, Alvin G; Hamilton, Paul W; Henry, Jonathan J

2010-11-01

G-protein-coupled receptors (GPCRs) represent diverse, multifamily groups of cell signaling receptors involved in many cellular processes. We identified Xenopus laevis GPR84 as a member of the A18 subfamily of GPCRs. During development, GPR84 is detected in the embryonic lens placode, differentiating lens fiber cells, retina, and cornea. Anti-sense morpholino oligonucleotide-mediated knockdown and RNA rescue experiments demonstrate GPR84's importance in lens, cornea, and retinal development. Examination of cell proliferation using an antibody against histone H3 S10P reveals significant increases in the lens and retina following GPR84 knockdown. Additionally, there was also an increase in apoptosis in the retina and lens, as revealed by TUNEL assay. Reciprocal transplantation of the presumptive lens ectoderm between uninjected controls and morpholino-injected embryos demonstrates that GPR84 is necessary in the retina for proper development of the retina, as well as other eye tissues including the lens and cornea. © 2010 Wiley-Liss, Inc.

The G-protein-coupled receptor, GPR84, is important for eye development in Xenopus laevis

PubMed Central

Perry, Kimberly J.; Johnson, Verity R.; Malloch, Erica L.; Fukui, Lisa; Wever, Jason; Thomas, Alvin G.; Hamilton, Paul W.; Henry, Jonathan J.

2010-01-01

G-protein-coupled receptors (GPCRs) represent diverse, multifamily groups of cell signaling receptors involved in many cellular processes. We identified Xenopus laevis GPR84 as a member of the A18 subfamily of GPCRs. During development, GPR84 is detected in the embryonic lens placode, differentiating lens fiber cells, retina and cornea. Anti-sense morpholino oligonucleotide-mediated knockdown and RNA rescue experiments demonstrate GPR84’s importance in lens, cornea and retinal development. Examination of cell proliferation using an antibody against histone H3 S10P reveals significant increases in the lens and retina following GPR84 knockdown. Additionally, there was also an increase in apoptosis in the retina and lens, as revealed by TUNEL assay. Reciprocal transplantation of the presumptive lens ectoderm between uninjected controls and morpholino injected embryos demonstrates that GPR84 is necessary in the retina for proper development of the retina, as well as other eye tissues including the lens and cornea. PMID:20925114

Nudging Our Way to a Healthier Population: The Effect of Calorie Labeling and Self-Control on Menu Choices of Emerging Adults.

PubMed

Rising, Camella J; Bol, Nadine

2017-08-01

Emerging adults are among those in the United States with concerning rates of overweight and obesity, putting them at risk for chronic diseases. One proposed intervention to address these issues across populations is to require that chain restaurants and similar establishments provide nutrition information, such as calorie labels, on menu items. This study therefore aims to examine the effect of menu calorie labeling and self-control on food and beverage choices of emerging adults. Results of a between-subjects experiment (n = 179) revealed that calorie labeling increased the likelihood of choosing lower calorie food and beverage options. Moreover, calorie labeling only led to selecting a lower calorie food option among those with high self-control, but not among those with low self-control. This moderating effect was not revealed for beverage choice. Public health practitioners and policymakers should consider intervention approaches that address other drivers of choice, such as self-control, in addition to nutrition information.

Effect of drug efflux transporters on placental transport of antiretroviral agent abacavir.

PubMed

Neumanova, Zuzana; Cerveny, Lukas; Greenwood, Susan L; Ceckova, Martina; Staud, Frantisek

2015-11-01

Abacavir is as a frequent part of combination antiretroviral therapy used in pregnant women. The aim of this study was to investigate, using in vitro, in situ and ex vivo experimental approaches, whether the transplacental pharmacokinetics of abacavir is affected by ATP-binding cassette (ABC) efflux transporters functionally expressed in the placenta: P-glycoprotein (ABCB1), breast cancer resistance protein (ABCG2), multidrug resistance-associated protein 2 (ABCC2) and multidrug resistance-associated protein 5 (ABCC5). In vitro transport assays revealed that abacavir is a substrate of human ABCB1 and ABCG2 transporters but not of ABCC2 or ABCC5. In addition, in situ experiments using dually perfused rat term placenta confirmed interactions of abacavir with placental Abcb1/Abcg2. In contrast, uptake studies in human placental villous fragments did not reveal any interaction of abacavir with efflux transporters suggesting a large contribution of passive diffusion and/or influx mechanisms to net transplacental abacavir transfer. Copyright © 2015 Elsevier Inc. All rights reserved.

Adolescents’ Pregnancy Intentions, Wantedness, and Regret: Cross-Lagged Relations With Mental Health and Harsh Parenting

PubMed Central

East, Patricia L.; Chien, Nina C.; Barber, Jennifer S.

2011-01-01

The authors used cross-lagged analyses to examine the across-time influences on and consequences of adolescents’ pregnancy intentions, wantedness, and regret. One hundred pregnant Latina adolescents were studied during pregnancy and at 6 and 12 months postpartum. The results revealed 4 main findings: (a) similar to what has been found in adult women, adolescents’ lower prenatal pregnancy intendedness and wantedness predicted initial difficulties in parenting; (b) frequent depression symptoms predicted subsequent lower pregnancy intendedness and wantedness; (c) adolescents’ poor mental health and harsh parenting of their child predicted subsequent higher childbearing regret, and (d) high childbearing regret and parenting stress were reciprocally related across time. In addition, adolescents’ wantedness of their pregnancy declined prenatally to postbirth, and strong pregnancy intendedness and wantedness were not concurrently related to adolescents’ poor prenatal mental health. The findings reveal how adolescents’ thoughts and feelings about their pregnancies are influenced by and predictive of their mental health and parenting experiences. PMID:22544975

Terasonic Excitations in 2D Gold Nanoparticle Arrays in a Water Matrix as Revealed by Atomistic Simulations

DOE PAGES

Bolmatov, Dima; Zhernenkov, Mikhail; Zav’yalov, Dmitry; ...

2016-08-19

Here in this work we report on terahertz phononic excitations in 2D gold nanoparticle arrays in a water matrix through a series of large-scale molecular dynamics simulations. For the first time, we observe acoustic Dirac-like crossings in H (H 2O) atomic (molecular) networks which emerge due to an intraband phononic scattering. These crossings are the phononic fingerprints of ice-like arrangements of H (H 2O) atomic (molecular) networks at nanometer scale. We reveal how phononic excitations in metallic nanoparticles and the water matrix reciprocally impact on one another providing the mechanism for the THz phononics manipulation via structural engineering. In addition,more » we show that by tuning the arrangement of 2D gold nanoparticle assemblies the Au phononic polarizations experience sub-terahertz hybridization (Kohn anomaly) due to surface electron-phonon relaxation processes. This opens the way for the sound control and manipulation in soft matter metamaterials at nanoscale.« less

Attention orienting and inhibitory control across the different mood states in bipolar disorder: an emotional antisaccade task.

PubMed

García-Blanco, Ana C; Perea, Manuel; Salmerón, Ladislao

2013-12-01

An antisaccade experiment, using happy, sad, and neutral faces, was conducted to examine the effect of mood-congruent information on inhibitory control (antisaccade task) and attentional orienting (prosaccade task) during the different episodes of bipolar disorder (BD) - manic (n=22), depressive (n=25), and euthymic (n=24). A group of 28 healthy controls was also included. Results revealed that symptomatic patients committed more antisaccade errors than healthy individuals, especially with mood-congruent faces. The manic group committed more antisaccade errors in response to happy faces, while the depressed group tended to commit more antisaccade errors in response to sad faces. Additionally, antisaccade latencies were slower in BD patients than in healthy individuals, whereas prosaccade latencies were slower in symptomatic patients. Taken together, these findings revealed the following: (a) slow inhibitory control in BD patients, regardless of their episode (i.e., a trait), and (b) impaired inhibitory control restricted to symptomatic patients (i.e., a state). Copyright © 2013 Elsevier B.V. All rights reserved.

Anti-miR-33 therapy does not alter the progression of atherosclerosis in low-density lipoprotein receptor-deficient mice.

PubMed

Marquart, Tyler J; Wu, Judy; Lusis, Aldons J; Baldán, Ángel

2013-03-01

To determine the efficacy of long-term anti-miR-33 therapy on the progression of atherosclerosis in high-fat, high-cholesterol-fed Ldlr(-/-) mice. Ldlr(-/-) mice received saline, or control or anti-miR-33 oligonucleotides once a week for 14 weeks. The treatment was effective, as measured by reduced levels of hepatic miR-33 and increased hepatic expression of miR-33 targets. Analysis of plasma samples revealed an initial elevation in high-density lipoprotein cholesterol after 2 weeks of treatment that was not sustained by the end of the experiment. Additionally, we found a significant increase in circulating triglycerides in anti-miR-33-treated mice, compared with controls. Finally, examination of atheromata revealed no significant changes in the size or composition of lesions between the 3 groups. Prolonged silencing of miR-33 fails to maintain elevated plasma high-density lipoprotein cholesterol and does not prevent the progression of atherosclerosis in Ldlr(-/-) mice.

Mechanism of early postradiation changes in intensity of spontaneous chemoluminescence of blood serum. [X rays; rats

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

Baraboi, V.A.; Orel, V.E.; Sribnaya, A.F.

The effects of epinephrine and hydrocortisone on rat blood serum CL were tested under model conditions to analyze the possible role of biologically active compounds in the pathogenesis of the described postradiation changes. Injection of epinephrine in a concentration of 50 ..mu..g/kg, induced a rapid and substantial decline of CL followed by normalization. Addition of epinephrine directly to bovine blood serum in a model experiment, with access of atmospheric oxygen, caused progressive increase in CL with increase in dosage and exposure time. This experiment demonstrates the capacity of epinephrine to interact directly with oxygen, acting as a watersoluble antioxidant. Intraperitonealmore » injections of hydrocortisone revealed a marked decline of CL under these conditions. Direct addition of hydrocortisone to blood serum under model conditions did not affect its CL. Thus, the antioxidant effect of hydrocortisone is mediated in nature. The data indicate that postradiation increase in incretion of epinephrine and corticosteroids can explain the decrease in blood serum CL of rats exposed to lethal radiation. Since the reaction of the adrenosympathetic and adrenohypophyseal systems to total-body irradiation is a manifestation of a nonspecific stress reaction; the decreased intensity of blood serum CL is probably also a component of this reaction. (ERB)« less

Hydration Resistance of Y2O3 Doped CaO and Its Application to Melting Titanium Alloys

NASA Astrophysics Data System (ADS)

Fanlong, Meng; Zhiwei, Cheng; Guangyao, Chen; Xionggang, Lu; Chonghe, Li

Various amount Y2O3(1-8 mol%) doped CaO powder was synthesized by the solid state reaction method, the pellete and crucible were fabricated by the cold isostatic pressing and were sintered at 1750°C for 4h. The microstructural characterization was revealed by X-ray diffraction(XRD) and scanning electron microscopy(SEM).The XRD results showed that when Y2O3 doped 2 mol%, metastable CaY2O4 phase existed in CaO grain boundary, when Y2O3 doped 3 mol%-8 mol%, in addition to the above structure, Y2O3 phase also be found in CaO grain boundary. Hydration experiment results showed when Y2O3 doped 0 mol%-4 mol%, CaO had excellent hydration resistance performance, Y2O3 doped 2 mol% had the best hydration resistance, its weight addition stored after 7 weeks (49 days) was only about 0.2 wt%. Melting experiment results showed that it was no reaction between crucible and alloy layer. Oxygen, calcium, titanium, nickle and yttrium element not diffusion between the CaO crucible and TiNi alloy, it was no oxygen content increase after melting.

Interaction-Free Effects Between Distant Atoms

NASA Astrophysics Data System (ADS)

Aharonov, Yakir; Cohen, Eliahu; Elitzur, Avshalom C.; Smolin, Lee

2018-01-01

A Gedanken experiment is presented where an excited and a ground-state atom are positioned such that, within the former's half-life time, they exchange a photon with 50% probability. A measurement of their energy state will therefore indicate in 50% of the cases that no photon was exchanged. Yet other measurements would reveal that, by the mere possibility of exchange, the two atoms have become entangled. Consequently, the "no exchange" result, apparently precluding entanglement, is non-locally established between the atoms by this very entanglement. This quantum-mechanical version of the ancient Liar Paradox can be realized with already existing transmission schemes, with the addition of Bell's theorem applied to the no-exchange cases. Under appropriate probabilities, the initially-excited atom, still excited, can be entangled with additional atoms time and again, or alternatively, exert multipartite nonlocal correlations in an interaction free manner. When densely repeated several times, this result also gives rise to the Quantum Zeno effect, again exerted between distant atoms without photon exchange. We discuss these experiments as variants of interaction-free-measurement, now generalized for both spatial and temporal uncertainties. We next employ weak measurements for elucidating the paradox. Interpretational issues are discussed in the conclusion, and a resolution is offered within the Two-State Vector Formalism and its new Heisenberg framework.

Interaction-Free Effects Between Distant Atoms

NASA Astrophysics Data System (ADS)

Aharonov, Yakir; Cohen, Eliahu; Elitzur, Avshalom C.; Smolin, Lee

2017-12-01

A Gedanken experiment is presented where an excited and a ground-state atom are positioned such that, within the former's half-life time, they exchange a photon with 50% probability. A measurement of their energy state will therefore indicate in 50% of the cases that no photon was exchanged. Yet other measurements would reveal that, by the mere possibility of exchange, the two atoms have become entangled. Consequently, the "no exchange" result, apparently precluding entanglement, is non-locally established between the atoms by this very entanglement. This quantum-mechanical version of the ancient Liar Paradox can be realized with already existing transmission schemes, with the addition of Bell's theorem applied to the no-exchange cases. Under appropriate probabilities, the initially-excited atom, still excited, can be entangled with additional atoms time and again, or alternatively, exert multipartite nonlocal correlations in an interaction free manner. When densely repeated several times, this result also gives rise to the Quantum Zeno effect, again exerted between distant atoms without photon exchange. We discuss these experiments as variants of interaction-free-measurement, now generalized for both spatial and temporal uncertainties. We next employ weak measurements for elucidating the paradox. Interpretational issues are discussed in the conclusion, and a resolution is offered within the Two-State Vector Formalism and its new Heisenberg framework.

Cradle to third life: An autobiography of an African-American science educator

NASA Astrophysics Data System (ADS)

Caruthers-Jackson, Sarah

This inquiry used reflective autobiographical research to reveal my beliefs, values, and practices of science teaching by using participatory action research with two students of my science tutoring organization. Also, I conducted an ethnographic inquiry using African-American teachers to understand how my early schooling experiences influenced my beliefs, values, and science practices. I collected data for this inquiry from three African-American teachers through interview-conversation that were videotaped and audiotaped. In addition, I audiotaped two African-American students' tutoring practices along with students' and researcher's journals. The findings indicate that African-American teachers during the school years 1942-1954 used families, churches, and communities to secure teaching resources to provide equal education for their African-American students who received limited resources from the board of education. Also indicated was how African-American teachers instilled in their African-American students a level of motivation that remained with some African-American students for their future endeavors. This researcher's beliefs/values similar to those of her segregated teachers emerged from this action research. Researcher's additional beliefs/values arose out of emerging technologies in teaching science. However, I, as the researcher, believe that the origin of my beliefs/values occurred during those segregated, public school experiences at Monitor Schools during the school years 1942-1954.

Clinical experience of laboratory follow-up with noninvasive prenatal testing using cell-free DNA and positive microdeletion results in 349 cases.

PubMed

Schwartz, S; Kohan, M; Pasion, R; Papenhausen, P R; Platt, L D

2018-02-01

Screening via noninvasive prenatal testing (NIPT) involving the analysis of cell-free DNA (cfDNA) from plasma has become readily available to screen for chromosomal and DNA aberrations through maternal blood. This report reviews a laboratory's experience with follow-up of positive NIPT screens for microdeletions. Patients that were screened positive by NIPT for a microdeletion involving 1p, 4p, 5p, 15q, or 22q who underwent diagnostic studies by either chorionic villus sampling or amniocentesis were evaluated. The overall positive predictive value for 349 patients was 9.2%. When a microdeletion was confirmed, 39.3% of the cases had additional abnormal microarray findings. Unrelated abnormal microarray findings were detected in 11.8% of the patients in whom the screen positive microdeletion was not confirmed. Stretches of homozygosity in the microdeletion were frequently associated with a false positive cfDNA microdeletion result. Overall, this report reveals that while cfDNA analysis will screen for microdeletions, the positive predictive value is low; in our series it is 9.2%. Therefore, the patient should be counseled accordingly. Confirmatory diagnostic microarray studies are imperative because of the high percentage of false positives and the frequent additional abnormalities not delineated by cfDNA analysis. © 2018 John Wiley & Sons, Ltd.

West Nile virus in plasma is highly sensitive to methylene blue-light treatment.

PubMed

Mohr, Harald; Knüver-Hopf, Joseph; Gravemann, Ute; Redecker-Klein, Anette; Müller, Thomas H

2004-06-01

The epidemic of West Nile virus (WNV) in the US resulted in cases of transfusion-transmitted WNV. Effective pathogen reduction methods could have removed this infectious agent from the blood supply We have evaluated the efficacy of photodynamic treatment of fresh frozen plasma (FFP) with methylene blue (MB), a decontamination method applied in several European countries. FFP units (300 ml each) were spiked with WNV. MB was added, and the units were illuminated with white or monochromatic yellow light. WNV infectivity was determined by bioassay. WNV-RNA was quantitated by real-time PCR. The inactivation of WNV was investigated under standard and under suboptimal conditions, respectively. In addition, rechallenge experiments with multiple addition of WNV at maximal load (approx. 105 CFU/ml) and repeated illumination without replenishing MB were performed. Complete inactivation of WNV was achieved by MB (0.8-1 mmol/l) and illumination with white light (30,000-45,000 Lux) within 2 min. White yellow light 20-40 J/cm(2) (2.5-5 min) were sufficient for inactivation by 5.75 log10-steps. The rechallenge experiments revealed the substantial reserve capacity of the procedure to inactivate WNV. Quantitative PCR indicated that the viral RNA was rapidly destroyed. All experimental data demonstrate the enormous potency of phototreatment with MB to inactivate WNV in plasma.

Dissolved organic matter fluorescence at wavelength 275/342 nm as a key indicator for detection of point-source contamination in a large Chinese drinking water lake.

PubMed

Zhou, Yongqiang; Jeppesen, Erik; Zhang, Yunlin; Shi, Kun; Liu, Xiaohan; Zhu, Guangwei

2016-02-01

Surface drinking water sources have been threatened globally and there have been few attempts to detect point-source contamination in these waters using chromophoric dissolved organic matter (CDOM) fluorescence. To determine the optimal wavelength derived from CDOM fluorescence as an indicator of point-source contamination in drinking waters, a combination of field campaigns in Lake Qiandao and a laboratory wastewater addition experiment was used. Parallel factor (PARAFAC) analysis identified six components, including three humic-like, two tryptophan-like, and one tyrosine-like component. All metrics showed strong correlation with wastewater addition (r(2) > 0.90, p < 0.0001). Both the field campaigns and the laboratory contamination experiment revealed that CDOM fluorescence at 275/342 nm was the most responsive wavelength to the point-source contamination in the lake. Our results suggest that pollutants in Lake Qiandao had the highest concentrations in the river mouths of upstream inflow tributaries and the single wavelength at 275/342 nm may be adapted for online or in situ fluorescence measurements as an early warning of contamination events. This study demonstrates the potential utility of CDOM fluorescence to monitor water quality in surface drinking water sources. Copyright © 2015 Elsevier Ltd. All rights reserved.

Chronobiology of Melatonin beyond the Feedback to the Suprachiasmatic Nucleus-Consequences to Melatonin Dysfunction.

PubMed

Hardeland, Rüdiger

2013-03-12

The mammalian circadian system is composed of numerous oscillators, which gradually differ with regard to their dependence on the pacemaker, the suprachiasmatic nucleus (SCN). Actions of melatonin on extra-SCN oscillators represent an emerging field. Melatonin receptors are widely expressed in numerous peripheral and central nervous tissues. Therefore, the circadian rhythm of circulating, pineal-derived melatonin can have profound consequences for the temporal organization of almost all organs, without necessarily involving the melatonin feedback to the suprachiasmatic nucleus. Experiments with melatonin-deficient mouse strains, pinealectomized animals and melatonin receptor knockouts, as well as phase-shifting experiments with explants, reveal a chronobiological role of melatonin in various tissues. In addition to directly steering melatonin-regulated gene expression, the pineal hormone is required for the rhythmic expression of circadian oscillator genes in peripheral organs and to enhance the coupling of parallel oscillators within the same tissue. It exerts additional effects by modulating the secretion of other hormones. The importance of melatonin for numerous organs is underlined by the association of various diseases with gene polymorphisms concerning melatonin receptors and the melatonin biosynthetic pathway. The possibilities and limits of melatonergic treatment are discussed with regard to reductions of melatonin during aging and in various diseases.

Effects of increasing nitrogen and phosphorus concentrations on phytoplankton community growth and toxicity during Planktothrix blooms in Sandusky Bay, Lake Erie.

PubMed

Davis, Timothy W; Bullerjahn, George S; Tuttle, Taylor; McKay, Robert Michael; Watson, Susan B

2015-06-16

Sandusky Bay experiences annual toxic cyanobacterial blooms dominated by Planktothrix agardhii/suspensa. To further understand the environmental drivers of these events, we evaluated changes in the growth response and toxicity of the Planktothrix-dominated blooms to nutrient amendments with orthophosphate (PO4) and inorganic and organic forms of dissolved nitrogen (N; ammonium (NH4), nitrate (NO3) and urea) over the bloom season (June - October). We complemented these with a metagenomic analysis of the planktonic microbial community. Our results showed that bloom growth and microcystin (MC) concentrations responded more frequently to additions of dissolved N than PO4, and that the dual addition of NH4 + PO4 and Urea + PO4 yielded the highest MC concentrations in 54% of experiments. Metagenomic analysis confirmed that P. agardhii/suspensa was the primary MC producer. The phylogenetic distribution of nifH revealed that both heterocystous cyanobacteria and heterotrophic proteobacteria had the genetic potential for N2 fixation in Sandusky Bay. These results suggest that as best management practices are developed for P reductions in Sandusky Bay, managers must be aware of the negative implications of not managing N loading into this system as N may significantly impact cyanobacterial bloom size and toxicity.

The mechanism of collagen cross-linking in diabetes: a puzzle nearing resolution.

PubMed

Monnier, V M; Glomb, M; Elgawish, A; Sell, D R

1996-07-01

Considerable interest has been focused in recent years on the mechanism of collagen cross-linking by high glucose in vitro and in vivo. Experiments in both diabetic humans and in animals have shown that over time collagen becomes less soluble, less digestible by collagenase, more stable to heat-induced denaturation, and more glycated. In addition, collagen becomes more modified by advanced products of the Maillard reaction, i.e., immunoreactive advanced glycation end products and the glycoxidation markers carboxymethyllysine and pentosidine. Mechanistic studies have shown that collagen cross-linking in vitro can be uncoupled from glycation by the use of antioxidants and chelating agents. Experiments in the authors' laboratory revealed that approximately 50% of carboxymethyllysine formed in vitro originates from pathways other than oxidation of Amadori products, i.e., most likely the oxidation of Schiff base-linked glucose. In addition, the increase in thermal stability of rat tail tendons exposed to high glucose in vitro or in vivo was found to strongly depend on H2O2 formation. The final missing piece of the puzzle is that of the structure of the major cross-link. We speculate that it is a nonfluorescent nonultraviolet active cross-link between two lysine residues, which includes a fragmentation product of glucose linked in a nonreducible bond labile to both strong acids and bases.

Deviation from additivity in mixture toxicity: relevance of nonlinear dose-response relationships and cell line differences in genotoxicity assays with combinations of chemical mutagens and gamma-radiation.

PubMed

Lutz, Werner K; Vamvakas, Spyros; Kopp-Schneider, Annette; Schlatter, Josef; Stopper, Helga

2002-12-01

Sublinear dose-response relationships are often seen in toxicity testing, particularly with bioassays for carcinogenicity. This is the result of a superimposition of various effects that modulate and contribute to the process of cancer formation. Examples are saturation of detoxification pathways or DNA repair with increasing dose, or regenerative hyperplasia and indirect DNA damage as a consequence of high-dose cytotoxicity and cell death. The response to a combination treatment can appear to be supra-additive, although it is in fact dose-additive along a sublinear dose-response curve for the single agents. Because environmental exposure of humans is usually in a low-dose range and deviation from linearity is less likely at the low-dose end, combination effects should be tested at the lowest observable effect levels (LOEL) of the components. This principle has been applied to combinations of genotoxic agents in various cellular models. For statistical analysis, all experiments were analyzed for deviation from additivity with an n-factor analysis of variance with an interaction term, n being the number of components tested in combination. Benzo[a]pyrene, benz[a]anthracene, and dibenz[a,c]anthracene were tested at the LOEL, separately and in combination, for the induction of revertants in the Ames test, using Salmonella typhimurium TA100 and rat liver S9 fraction. Combined treatment produced no deviation from additivity. The induction of micronuclei in vitro was investigated with ionizing radiation from a 137Cs source and ethyl methanesulfonate. Mouse lymphoma L5178Y cells revealed a significant 40% supra-additive combination effect in an experiment based on three independent replicates for controls and single and combination treatments. On the other hand, two human lymphoblastoid cell lines (TK6 and WTK1) as well as a pilot study with human primary fibroblasts from fetal lung did not show deviation from additivity. Data derived from one cell line should therefore not be generalized. Regarding the testing of mixtures for deviation from additive toxicity, the suggested experimental protocol is easily followed by toxicologists.

A polarimetric radar analysis of convection observed during NAME and TiMREX

NASA Astrophysics Data System (ADS)

Rowe, Angela Kay

2011-12-01

The mountainous regions of northwestern Mexico and southwestern Taiwan experience periods of intense rainfall associated with the North American and Asian monsoons, respectively, as warm, moist air is ushered onshore due to a reversal of mean low-level winds. Potentially unstable air is lifted along the steep topography, leading to convective initiation over the high peaks and adjacent foothills in both regions. In addition, an enhancement of convection in preexisting systems is observed due to interaction with the terrain, leading to localized heavy rain along the western slopes. The predictability of warm-reason rainfall in these regions is limited by the lack of understanding of the nature of these precipitating features, including the diurnal variability and elevation-dependent trends in microphysical processes. Using polarimetric data from NCAR's S-band, polarimetric radar (S-Pol), deployed during the North American Monsoon Experiment (NAME) and Terrain-influenced Monsoon Rainfall Experiment (TiMREX), individual convective elements were identified and tracked, allowing for an analysis of hydrometeor characteristics within evolving cells. Furthermore, a feature classification algorithm was applied to these datasets to compare characteristics associated with isolated convection to cells contained within organized systems. Examples of isolated cells from a range of topography during NAME revealed the presence of ZDR columns, attributed to the lofting of drops above the melting level, where subsequent freezing and growth by riming led to the production of graupel along the western slopes of the Sierra Madre Occidental (SMO) and adjacent coastal plain. Melting of large ice hydrometeors was also noted over higher terrain, leading to short-lived yet intense rainfall despite truncated warm-cloud depths compared to cells over the lower elevations. Cells embedded within mesoscale convective systems (MCSs) during NAME also displayed the combined roles of warm-rain and ice-based microphysical processes as convection organized along the terrain. In addition to enhancing precipitation along the western slopes of the SMO, melting ice contributed to the production of mesoscale outflow boundaries, which provided an additional focus mechanism for convective initiation over the lower elevations and resulted in propagation of these systems toward the coast. Intense rainfall was also observed along the Central Mountain Range (CMR) in Taiwan; however, in contrast to the systems during NAME, this enhancement occurred as MCSs moved onshore within the southwesterly flow and intercepted the CMR's steep slopes. Elevated maxima in polarimetric variables, similar to observations in convection during NAME, indicated a contribution from melting ice to rainfall at these higher elevations. Vertical profiles of ice mass, however, revealed greater amounts throughout the entire vertical depth of convection during NAME. In addition, isolated cells during TiMREX were relatively shallow compared to organized convection in both regions. Nonetheless, instantaneous rain rates were comparable during both experiments, suggesting efficient warm-rain processes within convection observed in the TiMREX radar domain and emphasizing a range of microphysical processes in these two regions. In addition, the greatest contribution to hourly accumulated rain mass in these regions was associated with deep organized systems along the western slopes, posing threats along the steep topography due to flash flooding and subsequent landslides, emphasizing the need for accurate prediction and understanding of the processes that lead to intense rainfall in these vulnerable regions.

The effect of Fe2NiO4 and Fe4NiO4Zn magnetic nanoparticles on anaerobic digestion activity.

PubMed

Chen, Jian Lin; Steele, Terry W J; Stuckey, David C

2018-06-11

Two types of magnetic nanoparticles (MNPs), i.e. Ni ferrite nanoparticles (Fe 2 NiO 4 ) and Ni Zn ferrite nanoparticles (Fe 4 NiO 4 Zn) containing the trace metals Ni and Fe, were added to the anaerobic digestion of synthetic municipal wastewater at concentrations between 1 and 100 mg Ni L -1 in order to compare their effects on biogas (methane) production and sludge activity. Using the production of methane over time as a measure, the assays revealed that anaerobic digestion was stimulated by the addition of 100 mg Ni L -1 in Fe 2 NiO 4 NPs, while it was inhibited by the addition of 1-100 mg Ni L -1 in Fe 4 NiO 4 Zn NPs. Especially at 100 mg Ni L -1 , Fe 4 NiO 4 Zn NPs resulted in a total inhibition of anaerobic digestion. The metabolic activity of the anaerobic sludge was tested using the resazurin reduction assay, and the assay clearly revealed the negative effect of Fe 4 NiO 4 Zn NPs and the positive effect of Fe 2 NiO 4 NPs. Re-feeding fresh synthetic medium reactivated the NPs added to the anaerobic sludge, except for the experiment with 100 mg Ni L -1 addition of Fe 4 NiO 4 Zn NPs. The findings in this present study indicate a possible new strategy for NPs design to enhance anaerobic digestion. Crown Copyright © 2018. Published by Elsevier B.V. All rights reserved.

A permeability transition in liver mitochondria and liposomes induced by α,ω-dioic acids and Ca(2+).

PubMed

Dubinin, Mikhail V; Samartsev, Victor N; Astashev, Maxim E; Kazakov, Alexey S; Belosludtsev, Konstantin N

2014-11-01

The article examines the molecular mechanism of the Ca(2+)-dependent cyclosporin A (CsA)-insensitive permeability transition in rat liver mitochondria induced by α,ω-dioic acids. The addition of α,ω-hexadecanedioic acid (HDA) to Ca(2+)-loaded liver mitochondria was shown to induce a high-amplitude swelling of the organelles, a drop of membrane potential and the release of Ca(2+) from the matrix, the effects being insensitive to CsA. The experiments with liposomes loaded with sulforhodamine B (SRB) revealed that, like palmitic acid (PA), HDA was able to cause permeabilization of liposomal membranes. However, the kinetics of HDA- and PA-induced release of SRB from liposomes was different, and HDA was less effective than PA in the induction of SRB release. Using the method of ultrasound interferometry, we also showed that the addition of Ca(2+) to HDA-containing liposomes did not change the phase state of liposomal membranes-in contrast to what was observed when Ca(2+) was added to PA-containing vesicles. It was suggested that HDA/Ca(2+)- and PA/Ca(2+)-induced permeability transition occurs by different mechanisms. Using the method of dynamic light scattering, we further revealed that the addition of Ca(2+) to HDA-containing liposomes induced their aggregation/fusion. Apparently, these processes result in a partial release of SRB due to the formation of fusion pores. The possibility that this mechanism underlies the HDA/Ca(2+)-induced permeability transition of the mitochondrial membrane is discussed.

Skeletal Muscle Metabolism in Duchenne and Becker Muscular Dystrophy-Implications for Therapies.

PubMed

Heydemann, Ahlke

2018-06-20

The interactions between nutrition and metabolism and skeletal muscle have long been known. Muscle is the major metabolic organ—it consumes more calories than other organs—and therefore, there is a clear need to discuss these interactions and provide some direction for future research areas regarding muscle pathologies. In addition, new experiments and manuscripts continually reveal additional highly intricate, reciprocal interactions between metabolism and muscle. These reciprocal interactions include exercise, age, sex, diet, and pathologies including atrophy, hypoxia, obesity, diabetes, and muscle myopathies. Central to this review are the metabolic changes that occur in the skeletal muscle cells of muscular dystrophy patients and mouse models. Many of these metabolic changes are pathogenic (inappropriate body mass changes, mitochondrial dysfunction, reduced adenosine triphosphate (ATP) levels, and increased Ca 2+ ) and others are compensatory (increased phosphorylated AMP activated protein kinase (pAMPK), increased slow fiber numbers, and increased utrophin). Therefore, reversing or enhancing these changes with therapies will aid the patients. The multiple therapeutic targets to reverse or enhance the metabolic pathways will be discussed. Among the therapeutic targets are increasing pAMPK, utrophin, mitochondrial number and slow fiber characteristics, and inhibiting reactive oxygen species. Because new data reveals many additional intricate levels of interactions, new questions are rapidly arising. How does muscular dystrophy alter metabolism, and are the changes compensatory or pathogenic? How does metabolism affect muscular dystrophy? Of course, the most profound question is whether clinicians can therapeutically target nutrition and metabolism for muscular dystrophy patient benefit? Obtaining the answers to these questions will greatly aid patients with muscular dystrophy.

Uptake, metabolism and sub-lethal effects of BDE-47 in two estuarine invertebrates with different trophic positions.

PubMed

Díaz-Jaramillo, M; Miglioranza, K S B; Gonzalez, M; Barón, E; Monserrat, J M; Eljarrat, E; Barceló, D

2016-06-01

Two microcosm types -sediment-biota and biota-biota- were constructed to simulate different pathways of BDE-47 uptake, metabolism and oxidative stress effects in two key estuarine invertebrates (polychaete Laeonereis acuta and crab Cyrtograpsus angulatus). In the sediment-biota experiment, both species were exposed to spiked sediments; an environmentally reported and a high concentration of BDE-47 for 2 weeks. In the biota-biota experiment, crabs were fed with polychaetes pre-exposed to BDE-47 in the sediment-biota experiment. The sediment-biota experiment first revealed that polychaetes significantly accumulated BDE-47 (biota-sediment accumulation factor >2; p < 0.05) to a much greater extent than the crab organs (muscle, hepatopancreas, gills) at both sediment concentrations. For oxidative stress responses, polychaete and crab tissues exposed to spiked sediment showed a significant increase (p < 0.05) of only glutathione S-transferase (GST) activity with respect to controls in both BDE-47 concentrations. No lipid peroxidation (TBARS) or total antioxidant capacity (ACAP) changes were evident in the species or organs exposed to either BDE-47 sediment concentration. The biota-biota experiment showed that feeding crabs with pre-exposed polychaetes caused BDE-47 accumulation in organs as well as significant amounts of BDE-47 eliminated through feces (p < 0.05). Unlike the sediment-biota exposure, crabs fed with pre-exposed BDE-47 polychaetes showed the most conspicuous oxidative stress responses. Significant changes in GST and ACAP in both hepatopancreas and gills, in addition to enhanced TBARS levels in the hepatopancreas with respect to controls (p < 0.05), revealed that BDE-47 assimilated by invertebrates represents a potential source of toxicity to their predators. No methoxylated metabolites (MeO-PBDEs) were detected during BDE-47 metabolism in the invertebrates in either of the two different exposure types. In contrast, hydroxylated metabolites (OH-PBDEs) were detected in polychaetes and crab organs/feces in both experiments. Our results demonstrate that PBDE hydroxylation is one of the main biotransformation routes of BDE-47 in estuarine animals, which could be associated with the oxidative stress responses found. Copyright © 2016 Elsevier Ltd. All rights reserved.

Active Dentate Granule Cells Encode Experience to Promote the Addition of Adult-Born Hippocampal Neurons

PubMed Central

Kirschen, Gregory W.; Shen, Jia; Wang, Jia; Man, Guoming; Wu, Song

2017-01-01

The continuous addition of new dentate granule cells (DGCs), which is regulated exquisitely by brain activity, renders the hippocampus plastic. However, how neural circuits encode experiences to affect the addition of adult-born neurons remains unknown. Here, we used endoscopic Ca2+ imaging to track the real-time activity of individual DGCs in freely behaving mice. For the first time, we found that active DGCs responded to a novel experience by increasing their Ca2+ event frequency preferentially. This elevated activity, which we found to be associated with object exploration, returned to baseline by 1 h in the same environment, but could be dishabituated via introduction to a novel environment. To transition seamlessly between environments, we next established a freely controllable virtual reality system for unrestrained mice. We again observed increased firing of active neurons in a virtual enriched environment. Interestingly, multiple novel virtual experiences increased the number of newborn neurons accumulatively compared with a single experience. Finally, optogenetic silencing of existing DGCs during novel environmental exploration perturbed experience-induced neuronal addition. Our study shows that the adult brain conveys novel, enriched experiences to increase the addition of adult-born hippocampal neurons by increasing the firing of active DGCs. SIGNIFICANCE STATEMENT Adult brains are constantly reshaping themselves from synapses to circuits as we encounter novel experiences from moment to moment. Importantly, this reshaping includes the addition of newborn hippocampal neurons. However, it remains largely unknown how our circuits encode experience-induced brain activity to govern the addition of new hippocampal neurons. By coupling in vivo Ca2+ imaging of dentate granule neurons with a novel, unrestrained virtual reality system for rodents, we discovered that a new experience increased firing of active dentate granule neurons rapidly and robustly. Exploration in multiple novel virtual environments, compared with a single environment, promoted dentate activation and enhanced the addition of new hippocampal neurons accumulatively. Finally, silencing this activation optogenetically during novel experiences perturbed experience-induced neuronal addition. PMID:28373391

High-density PhyloChip profiling of stimulated aquifer microbial communities reveals a complex response to acetate amendment

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

Handley, Kim M.; Wrighton, Kelly C.; Piceno, Yvette M.

2012-04-13

There is increasing interest in harnessing the functional capacities of indigenous microbial communities to transform and remediate a wide range of environmental contaminants. Information about which community members respond to stimulation can guide the interpretation and development of remediation approaches. To comprehensively determine community membership and abundance patterns among a suite of samples associated with uranium bioremediation experiments we employed a high-density microarray (PhyloChip). Samples were unstimulated, naturally reducing, or collected during Fe(III) (early) and sulfate reduction (late biostimulation) from an acetate re-amended/amended aquifer in Rifle, Colorado, and from laboratory experiments using field-collected materials. Deep community sampling with PhyloChip identifiedmore » hundreds-to-thousands of operational taxonomic units (OTUs) present during amendment, and revealed close similarity among highly enriched taxa from drill-core and groundwater well-deployed column sediment. Overall, phylogenetic data suggested stimulated community membership was most affected by a carryover effect between annual stimulation events. Nevertheless, OTUs within the Fe(III)- and sulfate-reducing lineages, Desulfuromonadales and Desulfobacterales, were repeatedly stimulated. Less consistent, co-enriched taxa represented additional lineages associated with Fe(III) and sulfate reduction (for example, Desulfovibrionales; Syntrophobacterales; Peptococcaceae) and autotrophic sulfur oxidation (Sulfurovum; Campylobacterales). These data imply complex membership among highly stimulated taxa, and by inference biogeochemical responses to acetate, a non-fermentable substrate.« less

Thermodynamic Effects of Noncoded and Coded Methionine Substitutions in Calmodulin

PubMed Central

Yamniuk, Aaron P.; Ishida, Hiroaki; Lippert, Dustin; Vogel, Hans J.

2009-01-01

The methionine residues in the calcium (Ca2+) regulatory protein calmodulin (CaM) are structurally and functionally important. They are buried within the N- and C-domains of apo-CaM but become solvent-exposed in Ca2+-CaM, where they interact with numerous target proteins. Previous structural studies have shown that methionine substitutions to the noncoded amino acids selenomethionine, ethionine, or norleucine, or mutation to leucine do not impact the main chain structure of CaM. Here we used differential scanning calorimetry to show that these substitutions enhance the stability of both domains, with the largest increase in melting temperature (19–26°C) achieved with leucine or norleucine in the apo-C-domain. Nuclear magnetic resonance spectroscopy experiments also revealed the loss of a slow conformational exchange process in the Leu-substituted apo-C-domain. In addition, isothermal titration calorimetry experiments revealed considerable changes in the enthalpy and entropy of target binding to apo-CaM and Ca2+-CaM, but the free energy of binding was largely unaffected due to enthalpy-entropy compensation. Collectively, these results demonstrate that noncoded and coded methionine substitutions can be accommodated in CaM because of the structural plasticity of the protein. However, adjustments in side-chain packing and dynamics lead to significant differences in protein stability and the thermodynamics of target binding. PMID:19217866

A new class of antibacterials, the imidazopyrazinones, reveal structural transitions involved in DNA gyrase poisoning and mechanisms of resistance.

PubMed

Germe, Thomas; Vörös, Judit; Jeannot, Frederic; Taillier, Thomas; Stavenger, Robert A; Bacqué, Eric; Maxwell, Anthony; Bax, Benjamin D

2018-05-04

Imidazopyrazinones (IPYs) are a new class of compounds that target bacterial topoisomerases as a basis for their antibacterial activity. We have characterized the mechanism of these compounds through structural/mechanistic studies showing they bind and stabilize a cleavage complex between DNA gyrase and DNA ('poisoning') in an analogous fashion to fluoroquinolones, but without the requirement for the water-metal-ion bridge. Biochemical experiments and structural studies of cleavage complexes of IPYs compared with an uncleaved gyrase-DNA complex, reveal conformational transitions coupled to DNA cleavage at the DNA gate. These involve movement at the GyrA interface and tilting of the TOPRIM domains toward the scissile phosphate coupled to capture of the catalytic metal ion. Our experiments show that these structural transitions are involved generally in poisoning of gyrase by therapeutic compounds and resemble those undergone by the enzyme during its adenosine triphosphate-coupled strand-passage cycle. In addition to resistance mutations affecting residues that directly interact with the compounds, we characterized a mutant (D82N) that inhibits formation of the cleavage complex by the unpoisoned enzyme. The D82N mutant appears to act by stabilizing the binary conformation of DNA gyrase with uncleaved DNA without direct interaction with the compounds. This provides general insight into the resistance mechanisms to antibiotics targeting bacterial type II topoisomerases.

A new class of antibacterials, the imidazopyrazinones, reveal structural transitions involved in DNA gyrase poisoning and mechanisms of resistance

PubMed Central

Germe, Thomas; Vörös, Judit; Jeannot, Frederic; Taillier, Thomas; Stavenger, Robert A; Bacqué, Eric; Bax, Benjamin D

2018-01-01

Abstract Imidazopyrazinones (IPYs) are a new class of compounds that target bacterial topoisomerases as a basis for their antibacterial activity. We have characterized the mechanism of these compounds through structural/mechanistic studies showing they bind and stabilize a cleavage complex between DNA gyrase and DNA (‘poisoning’) in an analogous fashion to fluoroquinolones, but without the requirement for the water–metal–ion bridge. Biochemical experiments and structural studies of cleavage complexes of IPYs compared with an uncleaved gyrase–DNA complex, reveal conformational transitions coupled to DNA cleavage at the DNA gate. These involve movement at the GyrA interface and tilting of the TOPRIM domains toward the scissile phosphate coupled to capture of the catalytic metal ion. Our experiments show that these structural transitions are involved generally in poisoning of gyrase by therapeutic compounds and resemble those undergone by the enzyme during its adenosine triphosphate-coupled strand-passage cycle. In addition to resistance mutations affecting residues that directly interact with the compounds, we characterized a mutant (D82N) that inhibits formation of the cleavage complex by the unpoisoned enzyme. The D82N mutant appears to act by stabilizing the binary conformation of DNA gyrase with uncleaved DNA without direct interaction with the compounds. This provides general insight into the resistance mechanisms to antibiotics targeting bacterial type II topoisomerases. PMID:29538767

Liver transplantation in patients with incidental hepatocellular carcinoma/cholangiocarcinoma and intrahepatic cholangiocarcinoma: a single-center experience.

PubMed

Elshamy, Mohammed; Presser, Naftali; Hammad, Abdulrahman Y; Firl, Daniel J; Coppa, Christopher; Fung, John; Aucejo, Federico N

2017-06-01

Reports of liver transplantation (LT) in patients with mixed hepatocellular carcinoma/cholangiocarcinoma (HCC/CC) and intrahepatic cholangiocarcinoma (ICC) are modest and have been mostly retrospective after pathological categorization in the setting of presumed HCC. Some studies suggest that patients undergoing LT with small and unifocal ICC or mixed HCC/CC can achieve about 40%-60% 5-year post-transplant survival. The study aimed to report our experience in patients undergoing LT with explant pathology revealing HCC/CC and ICC. From a prospectively maintained database, we performed cohort analysis. We identified 13 patients who underwent LT with explant pathology revealing HCC/CC or ICC. The observed recurrence rate post-LT was 31% (4/13) and overall survival was 85%, 51%, and 51% at 1, 3 and 5 years, respectively. Disease-free survival was 68%, 51%, and 41% at 1, 3 and 5 years, respectively. In our cohort, four patients would have qualified for exception points based on updated HCC Organ Procurement and Transplantation Network imaging guidelines. Lesions which lack complete imaging characteristics of HCC may warrant pre-LT biopsy to fully elucidate their pathology. Identified patients with early HCC/CC or ICC may benefit from LT if unresectable. Additionally, incorporating adjunctive perioperative therapies such as in the case of patients undergoing LT with hilar cholangiocarcinoma may improve outcomes but this warrants further investigation.

The dark side of technologies: technostress among users of information and communication technologies.

PubMed

Salanova, Marisa; Llorens, Susana; Cifre, Eva

2013-01-01

This paper tests the structure and the predictors of two psychological experiences of technostress associated with the use of information and communication technologies (ICT), i.e., technostrain (users report feelings of anxiety, fatigue, scepticism and inefficacy beliefs related to the use of technologies) and technoaddiction (users feel bad due to an excessive and compulsive use of these technologies). The study included a sample of 1072 ICT users (N = 675 nonintensive ICT users and N = 397 intensive ICT users). Results from multigroup confirmatory factor analyses among non-intensive and intensive ICT users showed, as expected, the four-factor structure of technostrain in both samples. Secondly, and also as expected, confirmatory factorial analyses revealed that technostress experiences are characterized not only by technostrain but also by an excessive and compulsive use of ICT. Moreover, multiple analyses of variance showed significant differences between non-intensive and intensive ICT users (1) in the dimensions of technostress and (2) in specific job demands and job/personal resources. Finally, linear multiple regression analyses revealed that technostrain is positively predicted by work overload, role ambiguity, emotional overload, mobbing and obstacles hindering ICT use, as well as by lack of autonomy, transformational leadership, social support, ICT use facilitators and mental competences. Work overload, role ambiguity and mobbing, as well as the lack of emotional competences, positively predict technoaddiction. Theoretical and practical implications, in addition to future research, are discussed.