Role of the oxyallyl substructure in the near infrared (NIR) absorption in symmetrical dye derivatives: A computational study.

PubMed

Prabhakar, Ch; Chaitanya, G Krishna; Sitha, Sanyasi; Bhanuprakash, K; Rao, V Jayathirtha

2005-03-24

It is well-known from experimental studies that the oxyallyl-substructure-based squarylium and croconium dyes absorb in the NIR region of the spectrum. Recently, another dye has been reported (J. Am. Chem. Soc. 2003, 125, 348) which contains the same basic chromophore, but the absorption is red-shifted by at least 300 nm compared to the former dyes and is observed near 1100 nm. To analyze the reasons behind the large red shift, in this work we have carried out symmetry-adapted cluster-configuration interaction (SAC-CI) studies on some of these NIR dyes which contain the oxyallyl substructure. From this study, contrary to the earlier reports, it is seen that the donor groups do not seem to play a major role in the red-shift of the absorption. On the other hand, on the basis of the results of the high-level calculations carried out here and using qualitative molecular orbital theory, it is observed that the orbital interactions play a key role in the red shift. Finally, design principles for the oxyallyl-substructure-based NIR dyes are suggested.

Masculine Norms, Avoidant Coping, Asian Values and Depression among Asian American Men.

PubMed

Iwamoto, Derek Kenji; Liao, Liang; Liu, William Ming

2010-01-01

Contrary to the "model minority" myth, growing research indicates that the rates of mental health problems among Asian Americans may be higher than initially assumed. This study seeks to add to the scant knowledge regarding the mental health of Asian American men by examining the role of masculine norms, coping and cultural values in predicting depression among this population (N=149). Results reveal that Asian American men who used avoidant coping strategies and endorsed the masculine norm Dominance reported higher levels of depressive symptoms. In contrast, endorsing Winning masculine norms was associated to lower levels of depressive symptoms. Findings suggest that adherence to masculine norms and avoidant coping strategies play a salient role in the mental health of Asian American men.

[The Relationship Between Marital Adjustment and Psychological Symptoms in Women: The Mediator Roles of Coping Strategies and Gender Role Attitudes].

PubMed

Yüksel, Özge; Dağ, İhsan

2015-01-01

The aim of this study were to investigate the mediator role of coping strategies and gender roles attitudes on the relationship between women's marital adjustment and psychological symptoms. 248 married women participated in the study. Participants completed Marital Adjustment Scale, Ways of Coping Questionnaire, Brief Symptom Inventory, Gender Role Attitudes Scale and Demographic Information Form. Regression analyses revealed that Submissive (Sobel z= -2.47, p<.01) and Helpless Coping Approach (Sobel z=-2.95, p<.001) have partial mediator role on the relationship between marital relationship score and psychological symptom level. Also, having Egalitarian Gender Role Attitude effects the psychological symptoms in relation with the marital relationship, but it is seen that this effect is not higher enough to play a mediator role (Sobel z =-1.21, p>.05). Regression analysis showed that there is a statistically significant correlation between women's marital adjustment and their psychological symptoms, indicating that the marital adjustment decreases as the psychological symptoms increases. It is also found out that submissive and helpless coping approach have mediator roles in this relationship. Also, contrary to expectations, having egalitarian gender role attitude effects the psychological symptoms in relation with the marital relationship, but this effect does not seem to play a mediator role. It is thought that the effects of marriage and couple therapy approaches considering couples’s problem solving and coping styles should be examined in further studies.

Response to ``Comment on `Excitations in photoactive molecules from quantum Monte Carlo' '' [J. Chem. Phys. 122, 087101 (2005)

NASA Astrophysics Data System (ADS)

Filippi, Claudia; Buda, Francesco

2005-02-01

We find that regions of the excited state potential energy surface of formaldimine, which are accessible from the Franck-Condon configuration, are incorrectly described by the restricted open-shell Kohn-Sham (ROKS) approach. In these regions, the deviations of the ROKS energies from the time-dependent density functional theory results are not a simple shift. Contrary to what is argued in the Comment by Doltsinis and Fink [J. Chem. Phys.XX, XXX (2004)], these differences can play a role in the excited state molecular dynamics of formaldimine at finite temperature.

Molecular induced skyhook effect for magnetic interlayer softening

NASA Astrophysics Data System (ADS)

Friedrich, Rico; Caciuc, Vasile; Atodiresei, Nicolae; Blügel, Stefan

2015-11-01

Our first-principles study demonstrates for the first time that by increasing the molecule-surface binding strength, the interlayer magnetic coupling of a ferromagnetic metal can be drastically reduced with respect to that of a clean substrate. Importantly, for a weakly chemisorbed molecule the rehybridization of metal atomic d states within the molecule-induced surface geometry (geometrical effect) plays a crucial role in obtaining interlayer magnetic softening. On the contrary, for a strongly chemisorbed molecule the interlayer magnetic coupling is further reduced due to an interplay between the geometrical effect and the hybridization of atomic d states with molecular ones.

The iron lung: halfway technology or necessary step?

PubMed

Maxwell, J H

1986-01-01

The iron lung is often used to epitomize the costly halfway technologies of modern-day medicine that fail to cure and only prolong a seriously compromised existence. Historical evidence indicates that the iron lung was not a costly instrument of last resort; instead, it was a lifesaving device that played a critical role in the evolution of modern respirators and respiratory care. Contrary to the prevailing views of the biomedical research community, the creation of new devices and instruments is often as important a source of technical change in medicine as are advances in the biological sciences.

Pretending to Play or Playing to Pretend: The Case of Autism

ERIC Educational Resources Information Center

Kasari, Connie; Chang, Ya-Chih; Patterson, Stephanie

2013-01-01

An article by Angeline S. Lillard and others published in the January 2013 issue of "Psychological Bulletin" about the impact of pretend play on child development raised a number of issues about play studies and child psychology. The article claimed that, contrary to current theories on the subject, the evidence of many studies does not…

Preschool Children's Social and Nonsocial Play Behaviours. Measurement and Correlations with Children's Playfulness, Behaviour Problems and Demographic Characteristics

ERIC Educational Resources Information Center

Rentzou, Konstantina

2014-01-01

Children's play contributes to their overall development. Yet, not all types of play have the same effects. On the contrary, nonsocial play has been found to be correlated with social, emotional and behavioural difficulties. The present study had a twofold aim. On the one hand it aimed at assessing Greek preschool children's social and nonsocial…

Longitudinal muscle of the esophagus: its role in esophageal health and disease.

PubMed

Mittal, Ravinder K

2013-07-01

The muscularis propria of the esophagus is organized into circular and longitudinal muscle layers. The function of the longitudinal muscle and its role in bolus propulsion are not clear. The goal of this review is to summarize what is known of the role of the longitudinal muscle in health, as well as in sensory and motor disorders of the esophagus. Simultaneous manometry and ultrasound imaging reveal that, during peristalsis, the two muscle layers of the esophagus contract in perfect synchrony. On the contrary, during transient lower esophageal sphincter (LES) relaxation, longitudinal muscle contracts independent of the circular muscle. Recent studies have provided novel insights into the role of the longitudinal muscle in LES relaxation and descending relaxation of the esophagus. In certain diseases (e.g. some motility disorders of the esophagus), there is discoordination between the two muscle layers, which likely plays an important role in the genesis of dysphagia and delayed esophageal emptying. There is close temporal correlation between prolonged contractions of the longitudinal muscles of the esophagus and esophageal 'angina-like' pain. Novel techniques to record longitudinal muscle contraction are reviewed. Longitudinal muscles of the esophagus play a key role in the physiology and pathophysiology of esophageal sensory and motor function. Neuro-pharmacologic controls of circular and longitudinal muscle are different, which provides an opportunity for the development of novel pharmacological therapies in the treatment of esophageal sensory and motor disorders.

The Power of Play: Learning What Comes Naturally

ERIC Educational Resources Information Center

Elkind, David

2008-01-01

Although under attack from some goal-oriented politicians and parents and ofen considered superfluous by school administrators and teachers, free play remains vital to human health and creativity. Contrary to the notion that play should serve utilitarian ends or consist primarily of organized sports, the author makes a case for self-initiated…

An RRM-containing mei2-like MCT1 plays a negative role in the seed germination and seedling growth of Arabidopsis thaliana in the presence of ABA.

PubMed

Gu, Lili; Jung, Hyun Ju; Kwak, Kyung Jin; Dinh, Sy Nguyen; Kim, Yeon-Ok; Kang, Hunseung

2016-12-01

Despite an increasing understanding of the essential role of the Mei2 gene encoding an RNA-binding protein (RBP) in premeiotic DNA synthesis and meiosis in yeasts and animals, the functional roles of the mei2-like genes in plant growth and development are largely unknown. Contrary to other mei2-like RBPs that contain three RNA-recognition motifs (RRMs), the mei2 C-terminal RRM only (MCT) is unique in that it harbors only the last C-terminal RRM. Although MCTs have been implicated to play important roles in plants, their functional roles in stress responses as well as plant growth and development are still unknown. Here, we investigated the expression and functional role of MCT1 (At1g37140) in plant response to abscisic acid (ABA). Confocal analysis of MCT1-GFP-expressing plants revealed that MCT1 is localized to the nucleus. The transcript level of MCT1 was markedly increased upon ABA treatment. Analysis of MCT1-overexpressing transgenic Arabidopsis plants and artificial miRNA-mediated mct1 knockdown mutants demonstrated that MCT1 inhibited seed germination and cotyledon greening of Arabidopsis plants under ABA. The transcript levels of ABA signaling-related genes, such as ABI3, ABI4, and ABI5, were markedly increased in the MCT1-overexpressing transgenic plant. Collectively, these results suggest that ABA-upregulated MCT1 plays a negative role in Arabidopsis seed germination and seedling growth under ABA by modulating the expression of ABA signaling-related genes. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Masculine Norms, Avoidant Coping, Asian Values and Depression among Asian American Men

PubMed Central

Iwamoto, Derek Kenji; Liao, Liang; Liu, William Ming

2010-01-01

Contrary to the “model minority” myth, growing research indicates that the rates of mental health problems among Asian Americans may be higher than initially assumed. This study seeks to add to the scant knowledge regarding the mental health of Asian American men by examining the role of masculine norms, coping and cultural values in predicting depression among this population (N=149). Results reveal that Asian American men who used avoidant coping strategies and endorsed the masculine norm Dominance reported higher levels of depressive symptoms. In contrast, endorsing Winning masculine norms was associated to lower levels of depressive symptoms. Findings suggest that adherence to masculine norms and avoidant coping strategies play a salient role in the mental health of Asian American men. PMID:20657794

Why cognitive science needs philosophy and vice versa.

PubMed

Thagard, Paul

2009-04-01

Contrary to common views that philosophy is extraneous to cognitive science, this paper argues that philosophy has a crucial role to play in cognitive science with respect to generality and normativity. General questions include the nature of theories and explanations, the role of computer simulation in cognitive theorizing, and the relations among the different fields of cognitive science. Normative questions include whether human thinking should be Bayesian, whether decision making should maximize expected utility, and how norms should be established. These kinds of general and normative questions make philosophical reflection an important part of progress in cognitive science. Philosophy operates best, however, not with a priori reasoning or conceptual analysis, but rather with empirically informed reflection on a wide range of findings in cognitive science. Copyright © 2009 Cognitive Science Society, Inc.

African American Women’s Reports of Racism during Hurricane Katrina: Variation by Interviewer Race

PubMed Central

Lowe, Sarah R.; Lustig, Kara; Marrow, Helen B.

2013-01-01

This study investigated the effects of interviewer race on low-income African American female hurricane survivors’ reports of racism during Hurricane Katrina and its aftermath (N = 41). Respondents were asked directly about the role of racism during the storm and evacuation by one of three interviewers (two White females and one African American female). Contrary to expectations, respondents were not significantly more likely to agree that racism played a role during the hurricane and its aftermath when with an African American interviewer compared to a White interviewer. However, when speaking to the White interviewers versus the African American interviewer, respondents were significantly more likely to use qualifying and contradictory statements and to make references to other races also being victims of the hurricane. PMID:23459229

Social behaviour and gut microbiota in red-bellied lemurs (Eulemur rubriventer): In search of the role of immunity in the evolution of sociality.

PubMed

Raulo, Aura; Ruokolainen, Lasse; Lane, Avery; Amato, Katherine; Knight, Rob; Leigh, Steven; Stumpf, Rebecca; White, Bryan; Nelson, Karen E; Baden, Andrea L; Tecot, Stacey R

2018-03-01

Vertebrate gut microbiota form a key component of immunity and a dynamic link between an individual and the ecosystem. Microbiota might play a role in social systems as well, because microbes are transmitted during social contact and can affect host behaviour. Combining methods from behavioural and molecular research, we describe the relationship between social dynamics and gut microbiota of a group-living cooperative species of primate, the red-bellied lemur (Eulemur rubriventer). Specifically, we ask whether patterns of social contact (group membership, group size, position in social network, individual sociality) are associated with patterns of gut microbial composition (diversity and similarity) between individuals and across time. Red-bellied lemurs were found to have gut microbiota with slight temporal fluctuations and strong social group-specific composition. Contrary to expectations, individual sociality was negatively associated with gut microbial diversity. However, position within the social network predicted gut microbial composition. These results emphasize the role of the social environment in determining the microbiota of adult animals. Since social transmission of gut microbiota has the potential to enhance immunity, microbiota might have played an escalating role in the evolution of sociality. © 2017 The Authors. Journal of Animal Ecology © 2017 British Ecological Society.

Hfq plays important roles in virulence and stress adaptation in Cronobacter sakazakii ATCC 29544.

PubMed

Kim, Seongok; Hwang, Hyelyeon; Kim, Kwang-Pyo; Yoon, Hyunjin; Kang, Dong-Hyun; Ryu, Sangryeol

2015-05-01

Cronobacter spp. are opportunistic pathogens that cause neonatal meningitis and sepsis with high mortality in neonates. Despite the peril associated with Cronobacter infection, the mechanisms of pathogenesis are still being unraveled. Hfq, which is known as an RNA chaperone, participates in the interaction with bacterial small RNAs (sRNAs) to regulate posttranscriptionally the expression of various genes. Recent studies have demonstrated that Hfq contributes to the pathogenesis of numerous species of bacteria, and its roles are varied between bacterial species. Here, we tried to elucidate the role of Hfq in C. sakazakii virulence. In the absence of hfq, C. sakazakii was highly attenuated in dissemination in vivo, showed defects in invasion (3-fold) into animal cells and survival (10(3)-fold) within host cells, and exhibited low resistance to hydrogen peroxide (10(2)-fold). Remarkably, the loss of hfq led to hypermotility on soft agar, which is contrary to what has been observed in other pathogenic bacteria. The hyperflagellated bacteria were likely to be attributable to the increased transcription of genes associated with flagellar biosynthesis in a strain lacking hfq. Together, these data strongly suggest that hfq plays important roles in the virulence of C. sakazakii by participating in the regulation of multiple genes. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

hfq Plays Important Roles in Virulence and Stress Adaptation in Cronobacter sakazakii ATCC 29544

PubMed Central

Kim, Seongok; Hwang, Hyelyeon; Kim, Kwang-Pyo; Yoon, Hyunjin; Kang, Dong-Hyun

2015-01-01

Cronobacter spp. are opportunistic pathogens that cause neonatal meningitis and sepsis with high mortality in neonates. Despite the peril associated with Cronobacter infection, the mechanisms of pathogenesis are still being unraveled. Hfq, which is known as an RNA chaperone, participates in the interaction with bacterial small RNAs (sRNAs) to regulate posttranscriptionally the expression of various genes. Recent studies have demonstrated that Hfq contributes to the pathogenesis of numerous species of bacteria, and its roles are varied between bacterial species. Here, we tried to elucidate the role of Hfq in C. sakazakii virulence. In the absence of hfq, C. sakazakii was highly attenuated in dissemination in vivo, showed defects in invasion (3-fold) into animal cells and survival (103-fold) within host cells, and exhibited low resistance to hydrogen peroxide (102-fold). Remarkably, the loss of hfq led to hypermotility on soft agar, which is contrary to what has been observed in other pathogenic bacteria. The hyperflagellated bacteria were likely to be attributable to the increased transcription of genes associated with flagellar biosynthesis in a strain lacking hfq. Together, these data strongly suggest that hfq plays important roles in the virulence of C. sakazakii by participating in the regulation of multiple genes. PMID:25754196

Livestock vaccine adoption among poor farmers in Bolivia: remembering innovation diffusion theory.

PubMed

Heffernan, Claire; Thomson, Kim; Nielsen, Louise

2008-05-02

The paper explores the low uptake of livestock vaccination among poor farming communities in Bolivia utilising core elements of the original innovation diffusion theory. Contrary to the recent literature, we found that vaccination behaviour was strongly linked to social and cultural, rather than economic, drivers. While membership in a group increased uptake, the 'hot' and 'cold' distinctions which dictate health versus illness within Andean cosmology also played a role, with vaccination viewed as a means of addressing underlying imbalances. We concluded that uptake of livestock vaccination was unlikely to improve without knowledge transfer that acknowledges local epistemologies for livestock disease.

Biology is more theoretical than physics.

PubMed

Gunawardena, Jeremy

2013-06-01

The word "theory" is used in at least two senses--to denote a body of widely accepted laws or principles, as in "Darwinian theory" or "quantum theory," and to suggest a speculative hypothesis, often relying on mathematical analysis, that has not been experimentally confirmed. It is often said that there is no place for the second kind of theory in biology and that biology is not theoretical but based on interpretation of data. Here, ideas from a previous essay are expanded upon to suggest, to the contrary, that the second kind of theory has always played a critical role and that biology, therefore, is a good deal more theoretical than physics.

[Economy in intensive care medicine--a contradiction?].

PubMed

Janssens, U

2015-05-01

Medical progress and demographic changes will lead to increasing budgetary constraints in the health care system in the coming years. With respect to economic, medical, and ethical aspects, intensive care medicine has a particular role within the health system. Nonetheless, financial restriction will be inevitable in the near future. A literature review was performed. In an era of economic decline accompanied by widespread recognition that healthcare costs are on a consistent upward spiral, rationalization and rationing are unavoidable. Priorization models will play a pivotal role in allocation of resources. Individual ethics (respect for autonomy, nonmaleficence, beneficence) as well as justice are essential in daily practice. Economic thinking and acting as well as being ethically responsible are not mutually exclusive. On the contrary, acting in an ethically responsible manner will be of considerable significance given the pressure of increasing costs in intensive care medicine.

Examining alcohol consumption with the theory of planned behaviour: Do health and alcohol knowledge play a role?

PubMed

Hasking, Penelope; Schofield, Lachlan

2015-01-01

We used the theory of planned behaviour (TPB) to investigate factors associated with alcohol consumption among university students, and to examine whether general or alcohol-specific health knowledge acts as a moderator in the relationship between elements of the theory and drinking behaviour. Participants were 258 Australian undergraduate university students (79% female) who completed an online questionnaire, assessing the constructs of interest. The hypothesis that intentions and behaviour would be successfully predicted using the theory was generally supported. Little evidence for the moderating effect of knowledge on the TPB variables was observed, although both general and alcohol-specific health knowledge moderated the relationship between intentions and behaviours. Contrary to expectation, more accurate knowledge strengthened this relationship. Further work is necessary to investigate the role of knowledge in limiting alcohol-related harms.

Unique roles of glucagon and glucagon-like peptides: Parallels in understanding the functions of adipokinetic hormones in stress responses in insects.

PubMed

Bednářová, Andrea; Kodrík, Dalibor; Krishnan, Natraj

2013-01-01

Glucagon is conventionally regarded as a hormone, counter regulatory in function to insulin and plays a critical anti-hypoglycemic role by maintaining glucose homeostasis in both animals and humans. Glucagon performs this function by increasing hepatic glucose output to the blood by stimulating glycogenolysis and gluconeogenesis in response to starvation. Additionally it plays a homeostatic role by decreasing glycogenesis and glycolysis in tandem to try and maintain optimal glucose levels. To perform this action, it also increases energy expenditure which is contrary to what one would expect and has actions which are unique and not entirely in agreement with its role in protection from hypoglycemia. Interestingly, glucagon-like peptides (GLP-1 and GLP-2) from the major fragment of proglucagon (in non-mammalian vertebrates, as well as in mammals) may also modulate response to stress in addition to their other physiological actions. These unique modes of action occur in response to psychological, metabolic and other stress situations and mirror the role of adipokinetic hormones (AKHs) in insects which perform a similar function. The findings on the anti-stress roles of glucagon and glucagon-like peptides in mammalian and non-mammalian vertebrates may throw light on the multiple stress responsive mechanisms which operate in a concerted manner under regulation by AKH in insects thus functioning as a stress responsive hormone while also maintaining organismal homeostasis. Copyright © 2012 Elsevier Inc. All rights reserved.

The polygalacturonase FaPG1 gene plays a key role in strawberry fruit softening

PubMed Central

García-Gago, Juan A; Posé, Sara; Muñoz-Blanco, Juan; Quesada, Miguel A

2009-01-01

The loss of firm texture is one of the most characteristic physiological processes that occur during the ripening of fleshy fruits. It is generally accepted that the disassembly of primary cell wall and middle lamella is the main factor involved in fruit softening. In this process, polygalacturonase (PG) has been implicated in the degradation of the polyuronide network in several fruits. However, the minor effect of PG downregulation on tomato softening, reported during the nineties, minimized the role of this enzyme in softening. Further works in other fruits are challenging this general assumption, as is occurring in strawberry. The strawberry (Fragaria × ananassa) fruit undergoes an extensive and fast softening that limit its shelf life and postharvest. Traditionally, it has also been considered that PG plays a minor role on this process, due to the low PG activity found in ripened strawberry fruits. Transgenic strawberry plants expressing an antisense sequence of the ripening-specific PG gene FaPG1 have been generated to get an insight into the role of this gene in softening. Half of the transgenic lines analyzed yielded fruits significantly firmer than control, without being affected other fruit parameters such as weight, color or soluble solids. The increase on firmness was maintained after several days of posharvest. In these firmer lines, FaPG1 was silenced to 95%, but total PG activity was only minor reduced. At the cell wall level, transgenic fruits contained a higher amount of covalently bound pectins whereas the soluble fraction was diminished. A microarray analysis of genes expressed in ripened receptacle did not show any significant change between control and transgenic fruits. Thus, contrary to the most accepted view, it is concluded that PG plays a key role on pectin metabolism and softening of strawberry fruit. PMID:19820312

The polygalacturonase FaPG1 gene plays a key role in strawberry fruit softening.

PubMed

García-Gago, Juan A; Posé, Sara; Muñoz-Blanco, Juan; Quesada, Miguel A; Mercado, José A

2009-08-01

The loss of firm texture is one of the most characteristic physiological processes that occur during the ripening of fleshy fruits. It is generally accepted that the disassembly of primary cell wall and middle lamella is the main factor involved in fruit softening. In this process, polygalacturonase (PG) has been implicated in the degradation of the polyuronide network in several fruits. However, the minor effect of PG downregulation on tomato softening, reported during the nineties, minimized the role of this enzyme in softening. Further works in other fruits are challenging this general assumption, as is occurring in strawberry. The strawberry (Fragaria x ananassa) fruit undergoes an extensive and fast softening that limit its shelf life and postharvest. Traditionally, it has also been considered that PG plays a minor role on this process, due to the low PG activity found in ripened strawberry fruits. Transgenic strawberry plants expressing an antisense sequence of the ripening-specific PG gene FaPG1 have been generated to get an insight into the role of this gene in softening. Half of the transgenic lines analyzed yielded fruits significantly firmer than control, without being affected other fruit parameters such as weight, color or soluble solids. The increase on firmness was maintained after several days of posharvest. In these firmer lines, FaPG1 was silenced to 95%, but total PG activity was only minor reduced. At the cell wall level, transgenic fruits contained a higher amount of covalently bound pectins whereas the soluble fraction was diminished. A microarray analysis of genes expressed in ripened receptacle did not show any significant change between control and transgenic fruits. Thus, contrary to the most accepted view, it is concluded that PG plays a key role on pectin metabolism and softening of strawberry fruit.

Role Overload, Role Self Distance, Role Stagnation as Determinants of Job Satisfaction and Turnover Intention in Banking Sector

PubMed Central

Kunte, Monica; Gupta, Priya; Bhattacharya, Sonali; Neelam, Netra

2017-01-01

Purpose: This study examined the relationship of the organizational role stress: Role overload, role self-distance, and role stagnation with job satisfaction and turnover intention with a sample of banking employees in India. Methodology: In this research, we used the RODS scale developed by Prohit and Pareek (2010) for measuring occupational role scale. The reliability of the scale came out to be 0.71. Findings: The majority of employees of all ranks, in both private and public sector banks, suffer from high role stress of all types. It was found that role overload and role stagnation are inversely associated with banking employees' job satisfaction. Private sector bank employees have more role stress and more unsatisfied than employees of public sector banks. Employees Turnover intention was found to be positively impacted by job satisfaction, contrary to many other studies. Possible reasons have been suggested. Job satisfaction was found to play a partial mediating role in the relationship between role overload and turnover intention with 40% mediation. Further, employees with longer tenure (work experience) have less role stress and are more satisfied. Originality: This study is unique in the sense there is hardly any study linking role stress to job satisfaction and turnover intention, specially in Indian context. PMID:29200554

Role Overload, Role Self Distance, Role Stagnation as Determinants of Job Satisfaction and Turnover Intention in Banking Sector.

PubMed

Kunte, Monica; Gupta, Priya; Bhattacharya, Sonali; Neelam, Netra

2017-01-01

This study examined the relationship of the organizational role stress: Role overload, role self-distance, and role stagnation with job satisfaction and turnover intention with a sample of banking employees in India. In this research, we used the RODS scale developed by Prohit and Pareek (2010) for measuring occupational role scale. The reliability of the scale came out to be 0.71. The majority of employees of all ranks, in both private and public sector banks, suffer from high role stress of all types. It was found that role overload and role stagnation are inversely associated with banking employees' job satisfaction. Private sector bank employees have more role stress and more unsatisfied than employees of public sector banks. Employees Turnover intention was found to be positively impacted by job satisfaction, contrary to many other studies. Possible reasons have been suggested. Job satisfaction was found to play a partial mediating role in the relationship between role overload and turnover intention with 40% mediation. Further, employees with longer tenure (work experience) have less role stress and are more satisfied. This study is unique in the sense there is hardly any study linking role stress to job satisfaction and turnover intention, specially in Indian context.

Role of photoacoustics in optogalvanics

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

Kumar, D.; McGlynn, S.P.

1990-09-15

Time-resolved laser optogalvanic (LOG) signals have been induced by pulsed laser excitation (l{ital s}{sub {ital j}}{r arrow}2{ital p}{sub {ital k}}, Paschen notation) of a {approximately}30 MHz radio-frequency (rf) discharge in neon at {approximately}5 torr. Dramatic changes of the shape/polarity of certain parts of the LOG signals occur when the rf excitation frequency is scanned over the electrical resonance peak of the plasma and the associated driving/detecting circuits. These effects are attributed to ionization rate changes (i.e., laser-induced alterations of the plasma conductivity), with concomitant variations in the plasma resonance characteristics. In addition to ionization rate changes, it is shown thatmore » photoacoustic (PA) effects also play a significant role in the generation of the LOG signal. Those parts of the LOG signal that are invariant with respect to the rf frequency are attributed to a PA effect. The similarity of LOG signal shapes from both rf and dc discharges suggests that photoacoustics play a similar role in the LOG effect in dc discharges. Contrary to common belief, most reported LOG signal profiles, ones produced by excitation to levels that do not lie close to the ionization threshold, appear to be totally mediated by the PA effect.« less

The mathematical review system: does reviewer status play a role in the citation process?

PubMed Central

2010-01-01

This paper revisits an aspect of citation theory (i.e., citer motivation) with respect to the Mathematical Review system and the reviewer’s role in mathematics. We focus on a set of journal articles (369) published in Singularity Theory (1974–2003), the mathematicians who wrote editorial reviews for these articles, and the number of citations each reviewed article received within a 5 year period. Our research hypothesis is that the cognitive authority of a high status reviewer plays a positive role in how well a new article is received and cited by others. Bibliometric evidence points to the contrary: Singularity Theorists of lower status (junior researchers) have reviewed slightly more well-cited articles (2–5 citations, excluding author self-citations) than their higher status counterparts (senior researchers). One explanation for this result is that lower status researchers may have been asked to review ‘trendy’ or more accessible parts of mathematics, which are easier to use and cite. We offer further explanations and discuss a number of implications for a theory of citation in mathematics. This research opens the door for comparisons to other editorial review systems, such as book reviews written in the social sciences or humanities. PMID:20543874

Unveiling the "secret" of play in dogs (Canis lupus familiaris): Asymmetry and signals.

PubMed

Cordoni, Giada; Nicotra, Velia; Palagi, Elisabetta

2016-08-01

Due to their playful propensity, dogs are a good model to test some hypotheses about play dynamics (length, asymmetry, features of players) and communication (play bow [PBOW]; relaxed open-mouth [ROM] display). We video-recorded 203 play sessions between dogs in an off-leash dog park in Palermo, Italy. Contrary to the expectation, play asymmetry (particularly high in this species) did not differ between stranger and familiar dogs, thus suggesting the limited role of play in forming dominance relationships. Asymmetry negatively affected the duration of the session, whereas the increasing number of players was positively linked to the duration of playful interactions. The number of PBOWs exchanged by players may exert a certain influence on the session length as well. PBOWs were performed independently from the kind of play (locomotor vs. contact) the dogs were engaging in. Conversely, ROMs were preferentially emitted during contact play when "face-to-face" interactions were more likely. Body closeness is also required in case opening the mouth has not a signal function but only preludes a bite. However, in the 82% of cases play bites did not follow a ROM, thus suggesting that dogs place ROMs in the appropriate context to optimize signal detectability. In conclusion, 2 tactics may concur in coping with the asymmetry and unpredictability of play sessions in dogs. First, whenever the asymmetry increases dogs shorten the duration of their sessions thus limiting the risk of possible escalation. Second, dogs make use of a good communicative system based on the reciprocal exchange of playful signals. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

[The passing eye: museums, public education, and the visualization of scientific evidence].

PubMed

Podgorny, Irina

2005-01-01

In this examination of certain issues related to the history of museums. An emphasis on the functions and missions entrusted to museums does not necessarily reflect the power museums have to create habits or shape meanings. To the contrary, this may reflect the actual fragility of museums and their need to resort to rhetoric to attract governmental favors and funds. Therefore, concentrating on the monumental, representative, or metaphorical aspects of museums obscures the history of these institutions and of their consolidated practices, there by naturalizing the separation between research space and public space and leaving the historian to play the role of an uninitiated observer of the 'cathedrals of science'.

How intergenerational interaction affects attitude-behavior inconsistency.

PubMed

Sekiguchi, Takuya; Nakamaru, Mayuko

2014-04-07

Social norms play an important role in maintaining social order, but at the same time, they can act as a constraint that compels people to take specific actions which run contrary to their attitudes. This paper treats the latter case: we investigate conditions in which attitude-behavior inconsistency persists, constructing mathematical models combining evolutionary games and cultural transmissions. In particular, we focus on the effect of intergenerational interactions. Our models show that both information about others' attitude (e.g., through social surveys) and the combination of intra- and inter-generational interactions are key factors to generate the situation where all people adopt the same behavior but different people have different attitudes. Copyright © 2013 Elsevier Ltd. All rights reserved.

Local symmetries and order-disorder transitions in small macroscopic Wigner islands.

PubMed

Coupier, Gwennou; Guthmann, Claudine; Noat, Yves; Jean, Michel Saint

2005-04-01

The influence of local order on the disordering scenario of small Wigner islands is discussed. A first disordering step is put in evidence by the time correlation functions and is linked to individual excitations resulting in configuration transitions, which are very sensitive to the local symmetries. This is followed by two other transitions, corresponding to orthoradial and radial diffusion, for which both individual and collective excitations play a significant role. Finally, we show that, contrary to large systems, the focus that is commonly made on collective excitations for such small systems through the Lindemann criterion has to be made carefully in order to clearly identify the relative contributions in the whole disordering process.

Does religion deserve a place in secular medicine?

PubMed

Earp, Brian D

2015-11-01

Biggar (2015) argues that "religion" deserves a place in secular medicine. Against this view, I argue that religion (as most people would understand the term) should not play a role in shaping secular health policy, and I provide some illustrations of the potential dangers of the contrary. However, I also suggest that-upon closer inspection-Biggar seems to be using the term "religion" to refer to obliquely to what most people would call "moral philosophy." On this less controversial interpretation, Biggar's proposal is inoffensive-but also unoriginal. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Stirred, Not Clumped: Evolution of Temperature Profiles in the Outskirts of Galaxy Clusters

NASA Astrophysics Data System (ADS)

Avestruz, Camille; Nagai, Daisuke; Lau, Erwin T.

2016-12-01

Recent statistical X-ray measurements of the intracluster medium (ICM) indicate that gas temperature profiles in the outskirts of galaxy clusters deviate from self-similar evolution. Using a mass-limited sample of galaxy clusters from cosmological hydrodynamical simulations, we show that the departure from self-similarity can be explained by non-thermal gas motions driven by mergers and accretion. Contrary to previous claims, gaseous substructures only play a minor role in the temperature evolution in cluster outskirts. A careful choice of halo overdensity definition in self-similar scaling mitigates these departures. Our work highlights the importance of non-thermal gas motions in ICM evolution and the use of galaxy clusters as cosmological probes.

Vortex matter stabilized by many-body interactions

NASA Astrophysics Data System (ADS)

Wolf, S.; Vagov, A.; Shanenko, A. A.; Axt, V. M.; Aguiar, J. Albino

2017-10-01

This work investigates interactions of vortices in superconducting materials between standard types I and II, in the domain of the so-called intertype (IT) superconductivity. Contrary to common expectations, the many-body (many-vortex) contribution is not a correction to the pair-vortex interaction here but plays a crucial role in the formation of the IT vortex matter. In particular, the many-body interactions stabilize vortex clusters that otherwise could not exist. Furthermore, clusters with large numbers of vortices become more stable when approaching the boundary between the intertype domain and type I. This indicates that IT superconductors develop a peculiar unconventional type of the vortex matter governed by the many-body interactions of vortices.

Study of the temperature configuration of parallel tempering for the traveling salesman problem

NASA Astrophysics Data System (ADS)

Hasegawa, Manabu

The effective temperature configuration of parallel tempering (PT) in finite-time optimization is studied for the solution of the traveling salesman problem. An experimental analysis is conducted to decide the relative importance of the two characteristic temperatures, the specific-heat-peak temperature referred to in the general guidelines and the effective intermediate temperature identified in the recent study on simulated annealing (SA). The results show that the operation near the former has no notable significance contrary to the conventional belief but that the operation near the latter plays a crucial role in fulfilling the optimization function of PT. The method shares the same origin of effectiveness with the SA and SA-related algorithms.

COX-2-derived endocannabinoid metabolites as novel inflammatory mediators.

PubMed

Alhouayek, Mireille; Muccioli, Giulio G

2014-06-01

Cyclooxygenase-2 (COX-2) is an enzyme that plays a key role in inflammatory processes. Classically, this enzyme is upregulated in inflammatory situations and is responsible for the generation of prostaglandins (PGs) from arachidonic acid (AA). One lesser-known property of COX-2 is its ability to metabolize the endocannabinoids, N-arachidonoylethanolamine (AEA) and 2-arachidonoylglycerol (2-AG). Endocannabinoid metabolism by COX-2 is not merely a means to terminate their actions. On the contrary, it generates PG analogs, namely PG-glycerol esters (PG-G) for 2-AG and PG-ethanolamides (PG-EA or prostamides) for AEA. Although the formation of these COX-2-derived metabolites of the endocannabinoids has been known for a while, their biological effects remain to be fully elucidated. Recently, several studies have focused on the role of these PG-G or PG-EA in vivo. In this review we take a closer look at the literature concerning these novel bioactive lipids and their role in inflammation. Copyright © 2014 Elsevier Ltd. All rights reserved.

The Arabidopsis transcription factor AtTCP15 regulates endoreduplication by modulating expression of key cell-cycle genes.

PubMed

Li, Zi-Yu; Li, Bin; Dong, Ai-Wu

2012-01-01

Plant cells frequently undergo endoreduplication, a modified cell cycle in which genome is repeatedly replicated without cytokinesis. As the key step to achieve final size and function for cells, endoreduplication is prevalent during plant development. However, mechanisms to control the balance between endoreduplication and mitotic cell division are still poorly understood. Here, we show that the Arabidopsis TCP (CINCINNATA-like TEOSINTE BRANCHED1-CYCLOIDEA-PCF)-family transcription factor gene AtTCP15 is expressed in trichomes, as well as in rapidly dividing and vascular tissues. Expression of AtTCP15SRDX, AtTCP15 fused with a SRDX repressor domain, induces extra endoreduplication in trichomes and cotyledon cells in transgenic Arabidopsis. On the contrary, overexpression of AtTCP15 suppresses endoreduplication in trichomes and other examined cells. Misregulation of AtTCP15 affects the expression of several important genes involved in cell-cycle regulation. AtTCP15 protein binds directly to the promoter regions of CYCA2;3 and RETINOBLASTOMA-RELATED (RBR) genes, which play key roles in endoreduplication. Taken together, AtTCP15 plays an important role in regulating endoreduplication during Arabidopsis development.

Effect of mesophilic lactobacilli and enterococci adjunct cultures on the final characteristics of a microfiltered milk Swiss-type cheese.

PubMed

Bouton, Yvette; Buchin, Solange; Duboz, Gabriel; Pochet, Sylvie; Beuvier, Eric

2009-04-01

The effect of four associations of adjunct cultures composed of mesophilic lactobacilli and enterococci, either solely or combined, on the microbiological, biochemical and sensory characteristics of Swiss-type cheese made using microfiltered cows' milk and supplemented with propionibacteria was studied. The global pattern of growth was similar to that generally observed in raw milk cheese and interactions between microflora were highlighted during ripening. Enterococci, which negatively affected the survival of streptococci starters, seemed to play a limited role in the formation of volatile compounds, probably due to their low levels throughout ripening. On the contrary, mesophilic lactobacilli, which affected the evolution of propionibacteria, enterococci and L. delbrueckii subsp. lactis starter counts, modified free amino acid content, production of volatile compounds and organoleptic properties of mature cheese. This population appeared to be of major importance in the formation of cheese flavor as it was positively related to numerous potential flavor compounds such as alcohols and their corresponding esters, acetaldehyde and 4-methyl-4-heptanone. The original mesophilic lactobacilli present in milk could play an important role in the sensorial diversity of raw milk Swiss-type cheeses such as Comte.

Interleukin-18 and CD30 serum levels in patients with moderate-severe depression.

PubMed Central

Merendino, Rosaria Alba; Di Rosa, Antonio Enrico; Di Pasquale, Giuseppe; Minciullo, Paola Lucia; Mangraviti, Carmela; Costantino, Antonella; Ruello, Antonella; Gangemi, Sebastiano

2002-01-01

Interleukin-18 (IL-18), a pro-inflammatory cytokine that plays an important role in the T-cell-helper type 1 response, is a new member of the family of cytokines produced in the brain. CD30 is a marker of T-cell-helper type 2 lymphocytes. We evaluated IL-18 and CD30 serum levels in 10 patients affected by moderate-severe depression (MSD). We demonstrated for the first time that serum IL-18 levels of MSD patients were significantly higher than those of healthy donors. On the contrary, no significant difference was found between serum CD30 levels of MSD patients compared with those of healthy donors. These data strengthen the hypothesis that MSD disease is associated with an inflammatory response, mainly T-cell-helper type 1, and suggest an important role for IL-18 in the pathophysiology of MSD. PMID:12396479

Naïve conceptions about multimedia learning: a study on primary school textbooks

PubMed Central

Colombo, Barbara; Antonietti, Alessandro

2013-01-01

HIGHLIGHTS This interview study explores beliefs about the instructional role of illustrationsWe compared illustrators', teachers', students' and common people's ideasParticipants' responses were internally coherent and close to multimedia learning theoryWe propose and discuss an integrated multimedia learning model An interview study, based on specific pictures taken from textbooks used in primary schools, was carried out to investigate illustrators', teachers', students', and common people's beliefs about the role that illustrations play in facilitating learning. Participants' responses were internally coherent, indicating a systematic nature of the underlying naïve conceptions. Findings disprove Mayer's pessimistic claim that laypersons' conceptions of multimedia learning fail to match experimentally supported principles and theories. On the contrary, interviewees spontaneously came very close to the multimedia learning theory, which states that students learn better from pictures, which fit specific cognitive principles. Implications for school instruction are highlighted. PMID:23908636

Role of viscous friction in the reverse rotation of a disk.

PubMed

de Castro, Pablo; Parisio, Fernando

2014-07-01

The mechanical response of a circularly driven disk in a dissipative medium is considered. We focus on the role played by viscous friction in the spinning motion of the disk, especially on the effect called reverse rotation, where the intrinsic and orbital rotations are antiparallel. Contrary to what happens in the frictionless case, where steady reverse rotations are possible, we find that this dynamical behavior may exist only as a transient when dissipation is considered. Whether or not reverse rotations in fact occur depends on the initial conditions and on two parameters, one related to dragging, inertia, and driving, the other associated with the geometric configuration of the system. The critical value of this geometric parameter (separating the regions where reverse rotation is possible from those where it is forbidden) as a function of viscosity is well adjusted by a q-exponential function.

Assessing the role of Hartree-Fock exchange, correlation energy and long range corrections in evaluating ionization potential, and electron affinity in density functional theory.

PubMed

Vikramaditya, Talapunur; Lin, Shiang-Tai

2017-06-05

Accurate determination of ionization potentials (IPs), electron affinities (EAs), fundamental gaps (FGs), and HOMO, LUMO energy levels of organic molecules play an important role in modeling and predicting the efficiencies of organic photovoltaics, OLEDs etc. In this work, we investigate the effects of Hartree Fock (HF) Exchange, correlation energy, and long range corrections in predicting IP and EA in Hybrid Functionals. We observe increase in percentage of HF exchange results in increase of IPs and decrease in EAs. Contrary to the general expectations inclusion of both HF exchange and correlation energy (from the second order perturbation theory MP2) leads to poor prediction. Range separated Hybrid Functionals are found to be more reliable among various DFT Functionals investigated. DFT Functionals predict accurate IPs whereas post HF methods predict accurate EAs. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

The key role of the scaffold on the efficiency of dendrimer nanodrugs

PubMed Central

Caminade, Anne-Marie; Fruchon, Séverine; Turrin, Cédric-Olivier; Poupot, Mary; Ouali, Armelle; Maraval, Alexandrine; Garzoni, Matteo; Maly, Marek; Furer, Victor; Kovalenko, Valeri; Majoral, Jean-Pierre; Pavan, Giovanni M.; Poupot, Rémy

2015-01-01

Dendrimers are well-defined macromolecules whose highly branched structure is reminiscent of many natural structures, such as trees, dendritic cells, neurons or the networks of kidneys and lungs. Nature has privileged such branched structures for increasing the efficiency of exchanges with the external medium; thus, the whole structure is of pivotal importance for these natural networks. On the contrary, it is generally believed that the properties of dendrimers are essentially related to their terminal groups, and that the internal structure plays the minor role of an ‘innocent' scaffold. Here we show that such an assertion is misleading, using convergent information from biological data (human monocytes activation) and all-atom molecular dynamics simulations on seven families of dendrimers (13 compounds) that we have synthesized, possessing identical terminal groups, but different internal structures. This work demonstrates that the scaffold of nanodrugs strongly influences their properties, somewhat reminiscent of the backbone of proteins. PMID:26169490

Naïve conceptions about multimedia learning: a study on primary school textbooks.

PubMed

Colombo, Barbara; Antonietti, Alessandro

2013-01-01

HIGHLIGHTSThis interview study explores beliefs about the instructional role of illustrationsWe compared illustrators', teachers', students' and common people's ideasParticipants' responses were internally coherent and close to multimedia learning theoryWe propose and discuss an integrated multimedia learning model An interview study, based on specific pictures taken from textbooks used in primary schools, was carried out to investigate illustrators', teachers', students', and common people's beliefs about the role that illustrations play in facilitating learning. Participants' responses were internally coherent, indicating a systematic nature of the underlying naïve conceptions. Findings disprove Mayer's pessimistic claim that laypersons' conceptions of multimedia learning fail to match experimentally supported principles and theories. On the contrary, interviewees spontaneously came very close to the multimedia learning theory, which states that students learn better from pictures, which fit specific cognitive principles. Implications for school instruction are highlighted.

A Novel Role of Three Dimensional Graphene Foam to Prevent Heater Failure during Boiling

PubMed Central

Ahn, Ho Seon; Kim, Ji Min; Park, Chibeom; Jang, Ji-Wook; Lee, Jae Sung; Kim, Hyungdae; Kaviany, Massoud; Kim, Moo Hwan

2013-01-01

We report a novel boiling heat transfer (NBHT) in reduced graphene oxide (RGO) suspended in water (RGO colloid) near critical heat flux (CHF), which is traditionally the dangerous limitation of nucleate boiling heat transfer because of heater failure. When the heat flux reaches the maximum value (CHF) in RGO colloid pool boiling, the wall temperature increases gradually and slowly with an almost constant heat flux, contrary to the rapid wall temperature increase found during water pool boiling. The gained time by NBHT would provide the safer margin of the heat transfer and the amazing impact on the thermal system as the first report of graphene application. In addition, the CHF and boiling heat transfer performance also increase. This novel boiling phenomenon can effectively prevent heater failure because of the role played by the self-assembled three-dimensional foam-like graphene network (SFG). PMID:23743619

Masculine and family honor and youth violence: The moderating role of ethnic-cultural affiliation.

PubMed

Khoury-Kassabri, Mona

2016-01-01

This study examines the involvement in violent behavior of at-risk Arab and Jewish male youth from a large city in Israel. It explores the role masculine and family honor plays in predicting youth involvement in violence and tests whether this association is moderated by ethnic-cultural affiliation. A total of 282 males (59.2% Arab), aged 15-21, filled out a self-report closed-ended questionnaire. We found that among both Jewish and Arab youth a greater concern with masculine honor was positively associated with involvement in violence. We also found that Arab youth are significantly more involved in violent behavior than Jewish youth, and that Arab participants were more concerned with masculine and family honor. However, contrary to what was expected, greater concern with family honor was associated with lower levels of Arab youth involvement in violence. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

The role of fatty acids and triglycerides in the gonads of Paracentrotus lividus from Sardinia: Growth, reproduction and cold acclimatization.

PubMed

Sanna, Roberta; Siliani, Silvia; Melis, Riccardo; Loi, Barbara; Baroli, Maura; Roggio, Tonina; Uzzau, Sergio; Anedda, Roberto

2017-09-01

A detailed characterization of lipid extracts from gonads of P. lividus over a year has been performed combining GC and NMR measurements. For this purpose, sea urchins from two different Sardinian coastal areas were collected monthly. The results underlined a correlation between gonad fatty acids profiles and both water temperature and reproduction process. In particular, EPA and ARA appear to be the most altered fatty acids following seasonal changes. It is suggested that EPA could represent a biomarker of reproduction, reaching a content around 14% during gametogenesis, mainly due to an increase of the sn-1,3 position in TAGs. On the contrary, ARA seems to play a more important role in response to cold acclimatization, which is reflected in a modulation of ARA content in the sn-1,3 position in TAGs. Copyright © 2017 Elsevier Ltd. All rights reserved.

Influences of source condition and dissolution on bubble plume in a stratified environment

NASA Astrophysics Data System (ADS)

Chu, Shigan; Prosperetti, Andrea

2017-11-01

A cross-sectionally averaged model is used to study a bubble plume rising in a stratified quiescent liquid. Scaling analyses for the peel height, at which the plume momentum vanishes, and the neutral height, at which its average density equals the ambient density, are presented. Contrary to a widespread practice in the literature, it is argued that the neutral height cannot be identified with the experimentally reported intrusion height. Recognizing this difference provides an explanation of the reason why the intrusion height is found so frequently to lie so much above predictions, and brings the theoretical results in line with observations. The mathematical model depends on three dimensionless parameters, some of which are related to the inlet conditions at the plume source. Their influence on the peel and neutral heights is illustrated by means of numerical results. Aside from the source parameters, we incorporate dissolution of bubbles and the corresponding density change of plume into the model. Contrary to what's documented in literature, density change of plume due to dissolution plays an important role in keeping the total buoyancy of plume, thus alleviating the rapid decrease of peel height because of dissolution.

Stressful life events and depressive symptoms in a post-war context: which informal support makes a difference?

PubMed

Jawad, May H; Sibai, Abla M; Chaaya, Monique

2009-03-01

Gerontological literature utilizes the life stress paradigm to understand the impact of stress on psychological well-being, as well as the protective role that social resources play in buffering those effects; however these relationships are not well understood within various historical and social contexts. Utilizing a sample of 490 community-residing older adults in post-civil war Lebanon, this study investigates the moderating role of various social support factors in the stress-depression relationship. Contrary to expectations, results suggest that older Lebanese are more susceptible to the effects of health-decline and serious accident events than other types of stressors such as losses in the family and financial problems. Furthermore, findings provide evidence for a differential protective role for the respondent's spouse and children for only certain stressful events. The discussion highlights the role of family as a stress buffer in a shifting physical, social and political environmental context. Results from this study add to the discourse by emphasizing the importance of understanding the saliency of the stressor as well as source of support provided.

Collaborative play in young children as a complex dynamic system: revealing gender related differences.

PubMed

Steenbeek, Henderien; van der Aalsvoort, Diny; van Geert, Paul

2014-07-01

This study was focused on the role of gender-related differences in collaborative play, by examining properties of play as a complex system, and by using micro-genetic analysis techniques. A complex dynamic systems model of dyadic play was used to make predictions with regard to duration and number of contact-episodes during play of same-sex dyads, both on the micro- (i.e., per individual session), meso- (i.e., in smoothed data), and macro time scale (i.e., the change over six consecutive play sessions). The empirical data came from a study that examined the collaborative play skills of children who experienced six twenty minute play sessions within a three week period of time. Monte Carlo permutation analyses were used to compare model predictions and empirical data. The findings point to strongly asymmetric distributions in the duration and number of contact episodes in all dyads over the six sessions, as a direct consequence of the underlying dynamics of the play system. The model prediction that girls-dyads would show longer contact episodes than boys-dyads was confirmed, but the prediction regarding the difference in number of peaks was not confirmed. In addition, the majority of the model predictions regarding changes over the course of six sessions were consistent with the data. That is, the average duration and the maximum duration of contact-episodes increases both in boys-dyads and girls-dyads, but differences occur in the strength of the increase. Contrary to expectation, the number of contact-episodes decreases both in boys-dyads and in girls-dyads.

Three-dimensional spin mapping of antiferromagnetic nanopyramids having spatially alternating surface anisotropy at room temperature.

PubMed

Wang, Kangkang; Smith, Arthur R

2012-11-14

Antiferromagnets play a key role in modern spintronic devices owing to their ability to modify the switching behavior of adjacent ferromagnets via the exchange bias effect. Consequently, detailed measurements of the spin structure at antiferromagnetic interfaces and surfaces are highly desirable, not only for advancing technologies but also for enabling new insights into the underlying physics. Here using spin-polarized scanning tunneling microscopy at room-temperature, we reveal in three-dimensions an orthogonal spin structure on antiferromagnetic compound nanopyramids. Contrary to expected uniaxial anisotropy based on bulk properties, the atomic terraces are found to have alternating in-plane and out-of-plane magnetic anisotropies. The observed layer-wise alternation in anisotropy could have strong influences on future nanoscale spintronic applications.

Causal structures in inflation

NASA Astrophysics Data System (ADS)

Ellis, George F. R.; Uzan, Jean-Philippe

2015-12-01

This article reviews the properties and limitations associated with the existence of particle, visual, and event horizons in cosmology in general and in inflationary universes in particular, carefully distinguishing them from 'Hubble horizons'. It explores to what extent one might be able to probe conditions beyond the visual horizon (which is close in size to the present Hubble radius), thereby showing that visual horizons place major limits on what are observationally testable aspects of a multiverse, if such exists. Indeed these limits largely prevent us from observationally proving a multiverse either does or does not exist. We emphasize that event horizons play no role at all in observational cosmology, even in the multiverse context, despite some claims to the contrary in the literature. xml:lang="fr"

Glaciers and Sea Level Rise

NASA Image and Video Library

2017-12-08

Calving front of the Perito Moreno Glacier (Argentina). Contrary to the majority of the glaciers from the southern Patagonian ice field, the Perito Moreno Glacier is currently stable. It is also one of the most visited glaciers in the world. To learn about the contributions of glaciers to sea level rise, visit: www.nasa.gov/topics/earth/features/glacier-sea-rise.html Credit: Etienne Berthier, Université de Toulouse NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

Scared and less noisy: glucocorticoids are associated with alarm call entropy

PubMed Central

Blumstein, Daniel T.; Chi, Yvonne Y.

2012-01-01

The nonlinearity and arousal hypothesis predicts that highly aroused mammals will produce nonlinear, noisy vocalizations. We tested this prediction by measuring faecal glucocorticoid metabolites (GCMs) in adult yellow-bellied marmots (Marmota flaviventris), and asking if variation in GCMs was positively correlated with Wiener entropy—a measure of noise. Contrary to our prediction, we found a significant negative relationship: marmots with more faecal GCMs produced calls with less noise than those with lower levels of GCMs. A previous study suggested that glucocorticoids modulate the probability that a marmot will emit a call. This study suggests that, like some other species, calls emitted from highly aroused individuals are less noisy. Glucocorticoids thus play an important, yet underappreciated role, in alarm call production. PMID:21976625

Scared and less noisy: glucocorticoids are associated with alarm call entropy.

PubMed

Blumstein, Daniel T; Chi, Yvonne Y

2012-04-23

The nonlinearity and arousal hypothesis predicts that highly aroused mammals will produce nonlinear, noisy vocalizations. We tested this prediction by measuring faecal glucocorticoid metabolites (GCMs) in adult yellow-bellied marmots (Marmota flaviventris), and asking if variation in GCMs was positively correlated with Wiener entropy-a measure of noise. Contrary to our prediction, we found a significant negative relationship: marmots with more faecal GCMs produced calls with less noise than those with lower levels of GCMs. A previous study suggested that glucocorticoids modulate the probability that a marmot will emit a call. This study suggests that, like some other species, calls emitted from highly aroused individuals are less noisy. Glucocorticoids thus play an important, yet underappreciated role, in alarm call production.

STIRRED, NOT CLUMPED: EVOLUTION OF TEMPERATURE PROFILES IN THE OUTSKIRTS OF GALAXY CLUSTERS

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

Avestruz, Camille; Nagai, Daisuke; Lau, Erwin T., E-mail: avestruz@uchicago.edu

Recent statistical X-ray measurements of the intracluster medium (ICM) indicate that gas temperature profiles in the outskirts of galaxy clusters deviate from self-similar evolution. Using a mass-limited sample of galaxy clusters from cosmological hydrodynamical simulations, we show that the departure from self-similarity can be explained by non-thermal gas motions driven by mergers and accretion. Contrary to previous claims, gaseous substructures only play a minor role in the temperature evolution in cluster outskirts. A careful choice of halo overdensity definition in self-similar scaling mitigates these departures. Our work highlights the importance of non-thermal gas motions in ICM evolution and the usemore » of galaxy clusters as cosmological probes.« less

The role of colonoscopy in managing diverticular disease of the colon.

PubMed

Tursi, Antonio

2015-03-01

Diverticulosis of the colon is frequently found on routine colonoscopy, and the incidence of diverticular disease and its complications appears to be increasing. The role of colonoscopy in managing this disease is still controversial. Colonoscopy plays a key role in managing diverticular bleeding. Several techniques have been effectively used in this field, but band ligation seems to be the best in preventing rebleeding. Colonoscopy is also effective in posing a correct differential diagnosis with other forms of chronic colitis involving colon harbouring diverticula (in particular with Crohn's disease or Segmental Colitis Associated with Diverticulosis). The role of colonoscopy to confirm diagnosis of uncomplicated diverticulitis is still under debate, since the risk of advanced colonic neoplasia in patients admitted for acute uncomplicated diverticulitis is not increased as compared to the average-risk population. On the contrary, colonoscopy is mandatory if patients complain of persistent symptoms or after resolution of an episode of complicated diverticulitis. Finally, a recent endoscopic classification, called Diverticular Inflammation and Complications Assessment (DICA), has been developed and validated. This classification seems to be a promising tool for predicting the outcome of the colon harboring diverticula, but further, prospective studies have to confirm its predictive role on the outcome of the disease.

Nonrandom Associations of Graphemes with Colors in Arabic.

PubMed

van Leeuwen, Tessa M; Dingemanse, Mark; Todil, Büşra; Agameya, Amira; Majid, Asifa

2016-01-01

Numerous studies demonstrate people associate colors with letters and numbers in systematic ways. But most of these studies rely on speakers of English, or closely related languages. This makes it difficult to know how generalizable these findings are, or what factors might underlie these associations. We investigated letter-color and number-color associations in Arabic speakers, who have a different writing system and unusual word structure compared to Standard Average European languages. We also aimed to identify grapheme-color synaesthetes (people who have conscious color experiences with letters and numbers). Participants associated colors with 28 basic Arabic letters and ten digits by typing color names that best fit each grapheme. We found language-specific principles determining grapheme-color associations. For example, the word formation process in Arabic was relevant for color associations. In addition, psycholinguistic variables, such as letter frequency and the intrinsic order of graphemes influenced associations. Contrary to previous studies we found no evidence for sounds playing a role in letter-color associations for Arabic, and only a very limited role for shape influencing color associations. These findings highlight the importance of linguistic and psycholinguistic features in cross-modal correspondences, and illustrate why it is important to play close attention to each language on its own terms in order to disentangle language-specific from universal effects.

Anosognosia as motivated unawareness: the 'defence' hypothesis revisited.

PubMed

Turnbull, Oliver H; Fotopoulou, Aikaterini; Solms, Mark

2014-12-01

Anosognosia for hemiplegia has seen a century of almost continuous research, yet a definitive understanding of its mechanism remains elusive. Essentially, anosognosic patients hold quasi-delusional beliefs about their paralysed limbs, in spite of all the contrary evidence, repeated questioning, and logical argument. We review a range of findings suggesting that emotion and motivation play an important role in anosognosia. We conclude that anosognosia involves (amongst other things) a process of psychological defence. This conclusion stems from a wide variety of clinical and experimental investigations, including data on implicit awareness of deficit, fluctuations in awareness over time, and dramatic effects upon awareness of psychological interventions such as psychotherapy, reframing of the emotional consequences of the paralysis, and first versus third person perspectival manipulations. In addition, we review and refute the (eight) arguments historically raised against the 'defence' hypothesis, including the claim that a defence-based account cannot explain the lateralised nature of the disorder. We argue that damage to a well-established right-lateralised emotion regulation system, with links to psychological processes that appear to underpin allocentric spatial cognition, plays a key role in anosognosia (at least in some patients). We conclude with a discussion of implications for clinical practice. Copyright © 2014 Elsevier Ltd. All rights reserved.

Induction of AGAMOUS gene expression plays a key role in ripening of tomato sepals in vitro.

PubMed

Ishida, B K; Jenkins, S M; Say, B

1998-03-01

In vitro culture of VFNT Cherry tomato sepals (calyx) at 16-21 degrees C results in developmental changes that are similar to those that occur in fruit tissue [10]. Sepals become swollen, red, and succulent, produce ethylene, and have increased levels of polygalacturonase RNA. They also produce many flavor volatiles characteristic of ripe tomato fruit and undergo similar changes in sugar content [11]. We examined the expression of the tomato AGAMOUS gene, TAG1, in ripening, in vitro sepal cultures and other tissues from the plant and found that TAG1 RNA accumulates to higher levels than expected from data from other plants. Contrary to reports on the absence of AGAMOUS in sepals, TAG1 RNA levels in green sepals from greenhouse-grown plants is detectable, its concentration increasing with in vitro ripening to levels that were even higher than in red, ripe fruit. Sepals of fruit on transgenic tomato plants that expressed TAG1 ectopically were induced by low temperature to ripen in vivo, producing lycopene and undergoing cell wall softening as is characteristic of pericarpic tissue. We therefore propose that the induction of elevated TAG1 gene expression plays a key role in developmental changes that result in sepal ripening.

EPHRIN-A5 REGULATES INTER-MALE AGGRESSION IN MICE

PubMed Central

Sheleg, Michal; Yochum, Carrie L.; Richardson, Jason R.; Wagner, George C.; Zhou, Renping

2015-01-01

The Eph family of receptor tyrosine kinases play key roles in both the patterning of the developing nervous system and neural plasticity in the mature brain. To determine functions of ephrin-A5, a GPI-linked ligand to the Eph receptors, in animal behavior regulations, we examined effects of its inactivation on male mouse aggression. When tested in the resident-intruder paradigm for offensive aggression, ephrin-A5-mutant animals (ephrin-A5−/−) exhibited severe reduction in conspecific aggression compared to wild-type controls. On the contrary, defensive aggression in the form of target biting was higher in ephrin-A5−/− mice, indicating that the mutant mice are capable of attacking behavior. In addition, given the critical role of olfaction in aggressive behavior, we examined the ability of the ephrin-A5−/− mice to smell and found no differences between the mutant and control animals. Testosterone levels in the mutant mice were also found to be within the normal range. Taken together, our data reveal a new role of ephrin-A5 in the regulation of aggressive behavior in mice. PMID:25746458

International Trade Drives Global Resource Use: A Structural Decomposition Analysis of Raw Material Consumption from 1990-2010.

PubMed

Plank, Barbara; Eisenmenger, Nina; Schaffartzik, Anke; Wiedenhofer, Dominik

2018-04-03

Globalization led to an immense increase of international trade and the emergence of complex global value chains. At the same time, global resource use and pressures on the environment are increasing steadily. With these two processes in parallel, the question arises whether trade contributes positively to resource efficiency, or to the contrary is further driving resource use? In this article, the socioeconomic driving forces of increasing global raw material consumption (RMC) are investigated to assess the role of changing trade relations, extended supply chains and increasing consumption. We apply a structural decomposition analysis of changes in RMC from 1990 to 2010, utilizing the Eora multi-regional input-output (MRIO) model. We find that changes in international trade patterns significantly contributed to an increase of global RMC. Wealthy developed countries play a major role in driving global RMC growth through changes in their trade structures, as they shifted production processes increasingly to less material-efficient input suppliers. Even the dramatic increase in material consumption in the emerging economies has not diminished the role of industrialized countries as drivers of global RMC growth.

Accidental death and the rule of joint and several liability

PubMed Central

Carvell, Daniel; Currie, Janet; MacLeod, W. Bentley

2013-01-01

Most U.S. states have enacted JSL reform, the move from a regime of joint and several liability (JSL) that allows plaintiffs to claim full recovery from any one of multiple defendants to one where defendants are held liable only for the harm they cause. Contrary to previous theoretical work, we show that JSL reform can increase precaution by judgment proof agent by giving “deep pockets” an incentive to reduce their own liability by bringing judgment-proof agents into court. This result can help explain our empirical findings showing that JSL reform reduces death rates (and hence increase precaution) for many types of accidents. Together, these results highlight the role that litigation costs and judgment-proof agents play in the functioning of the American tort system. PMID:25076808

Motivations for Social Media Use and Impact on Political Participation in China: A Cognitive and Communication Mediation Approach.

PubMed

Chen, Zhuo; Chan, Michael

2017-02-01

Integrating uses and gratifications theory and the cognitive/communication mediation model: this study examines Chinese students' use of social media and subsequent impact on political participation. An integrative framework is proposed where media use, political expression, and political cognitions (efficacy and knowledge) play important mediating roles between audience motivations and participation. Structural equation analyses showed support for the integrated model. Guidance and social utility motivations exhibited different indirect effects on online and offline participation through social media news, discussion, and political efficacy. Entertainment motivations exhibited no direct or indirect effects. Contrary to expectations and previous literature, surveillance motivations exhibited negative direct and indirect effects on offline participation, which may be attributed to the particular Chinese social and political context. Implications of the findings are discussed.

[Ambroise Paré in French literature].

PubMed

Dumaitre, P

1995-01-01

The 16th century by its passionate side has been the favourite one of authors of historical novels in which among the heroes of "cloak and dagger stories" appears sometime Ambroise Paré. Alexandre Dumas (the father) has shown him at the court of Charles IX in La Reine Margot (1845) where he does not however play a great role. On the contrary, Balzac in Le Martyr calviniste (1842) has given him a capital part close to the dying François II, whom he intended to trepanize but had to give up this idea as a consequence of the opposition of the queen-mother Catherine de Médicis. In the present century, Robert Merle in Paris ma bonne ville (Fortune de France, 3, 1980) shows Paré at the time of the Saint Barthélemy.

Sensitivities of Tropical Cyclones to Surface Friction and the Coriolis Parameter in a 2-D Cloud-Resolving Model

NASA Technical Reports Server (NTRS)

Chao, Winston C.; Chen, Baode; Tao, Wei-Kuo; Lau, William K. M. (Technical Monitor)

2002-01-01

The sensitivities to surface friction and the Coriolis parameter in tropical cyclogenesis are studied using an axisymmetric version of the Goddard cloud ensemble model. Our experiments demonstrate that tropical cyclogenesis can still occur without surface friction. However, the resulting tropical cyclone has very unrealistic structure. Surface friction plays an important role of giving the tropical cyclones their observed smaller size and diminished intensity. Sensitivity of the cyclogenesis process to surface friction. in terms of kinetic energy growth, has different signs in different phases of the tropical cyclone. Contrary to the notion of Ekman pumping efficiency, which implies a preference for the highest Coriolis parameter in the growth rate if all other parameters are unchanged, our experiments show no such preference.

Horizontal Hostility among Non-Meat Eaters

PubMed Central

Rothgerber, Hank

2014-01-01

The present study examined intergroup judgments made between four groups of non-meat eaters: health vegetarians; ethical vegetarians; health vegans, and ethical vegans. Consistent with hypotheses based on horizontal hostility and the need to maintain ingroup distinctiveness, ethical vegetarians gave unfavorable evaluations to health vegetarians relative to vegans, especially when the mainstream omnivore group was made salient. Contrary to expectations, vegans gave relatively more favorable evaluations to ethical vegetarians than health vegetarians when mainstream salience was low. This was especially true for vegans who were motivated primarily by ethical concerns. When mainstream salience was high, vegans did not distinguish between the vegetarian subgroups. Results suggest that one’s motives for abstaining from meat often play a larger role in this type of intergroup perceptions than one’s dietary practices. PMID:24809342

Long-term accumulation and microdistribution of uranium in the bone and marrow of beagle dog.

PubMed

Arruda-Neto, J D T; Manso Guevara, M V; Nogueira, G P; Taricano, I D; Saiki, M; Zamboni, C B; Bonamin, L V; Camargo, S P; Cestari, A C; Deppman, A; Garcia, F; Gouveia, A N; Guzman, F; Helene, O A M; Jorge, S A C; Likhachev, V P; Martins, M N; Mesa, J; Rodriguez, O; Vanin, V R

2004-08-01

The accumulation and microdistribution of uranium in the bone and marrow of Beagle dogs were determined by both neutron activation and neutron-fission analysis. The experiment started immediately after the weaning period, lasting till maturity. Two animal groups were fed daily with uranyl nitrate at concentrations of 20 and 100 microg g(-1) food. Of the two measuring techniques, uranium accumulated along the marrow as much as in the bone, contrary to the results obtained with single, acute doses. The role played by this finding for the evaluation of radiobiological long-term risks is discussed. It was demonstrated, by means of a biokinetical approach, that the long-term accumulation of uranium in bone and marrow could be described by a piling up of single dose daily incorporation.

Tumor Microenvironment and Immune Effects of Antineoplastic Therapy in Lymphoproliferative Syndromes

PubMed Central

Álvaro, Tomás; de la Cruz-Merino, Luis; Henao-Carrasco, Fernando; Villar Rodríguez, José Luis; Vicente Baz, David; Codes Manuel de Villena, Manuel; Provencio, Mariano

2010-01-01

Lymphomas represent a wide group of heterogenic diseases with different biological and clinical behavior. The underlying microenvironment-specific composition seems to play an essential role in this scenario, harboring the ability to develop successful immune responses or, on the contrary, leading to immune evasion and even promotion of tumor growth. Depending on surrounding lymphoid infiltrates, lymphomas may have different prognosis. Moreover, recent evidences have emerged that confer a significant impact of main lymphoma's treatment over microenvironment, with clinical consequences. In this review, we summarize these concepts from a pathological and clinical perspective. Also, the state of the art of lymphoma's anti-idiotype vaccine development is revised, highlighting the situations where this strategy has proven to be successful and eventual clues to obtain better results in the future. PMID:20814546

Do promises matter? An exploration of the role of promises in psychological contract breach.

PubMed

Montes, Samantha D; Zweig, David

2009-09-01

Promises are positioned centrally in the study of psychological contract breach and are argued to distinguish psychological contracts from related constructs, such as employee expectations. However, because the effects of promises and delivered inducements are confounded in most research, the role of promises in perceptions of, and reactions to, breach remains unclear. If promises are not an important determinant of employee perceptions, emotions, and behavioral intentions, this would suggest that the psychological contract breach construct might lack utility. To assess the unique role of promises, the authors manipulated promises and delivered inducements separately in hypothetical scenarios in Studies 1 (558 undergraduates) and 2 (441 employees), and they measured them separately (longitudinally) in Study 3 (383 employees). The authors' results indicate that breach perceptions do not represent a discrepancy between what employees believe they were promised and were given. In fact, breach perceptions can exist in the absence of promises. Further, promises play a negligible role in predicting feelings of violation and behavioral intentions. Contrary to the extant literature, the authors' findings suggest that promises may matter little; employees are concerned primarily with what the organization delivers.

The Role of Matrix Metalloproteinases in Diabetic Wound Healing in relation to Photobiomodulation.

PubMed

Ayuk, Sandra Matabi; Abrahamse, Heidi; Houreld, Nicolette Nadene

2016-01-01

The integration of several cellular responses initiates the process of wound healing. Matrix Metalloproteinases (MMPs) play an integral role in wound healing. Their main function is degradation, by removal of damaged extracellular matrix (ECM) during the inflammatory phase, breakdown of the capillary basement membrane for angiogenesis and cell migration during the proliferation phase, and contraction and remodelling of tissue in the remodelling phase. For effective healing to occur, all wounds require a certain amount of these enzymes, which on the contrary could be very damaging at high concentrations causing excessive degradation and impaired wound healing. The imbalance in MMPs may increase the chronicity of a wound, a familiar problem seen in diabetic patients. The association of diabetes with impaired wound healing and other vascular complications is a serious public health issue. These may eventually lead to chronic foot ulcers and amputation. Low intensity laser irradiation (LILI) or photobiomodulation (PBM) is known to stimulate several wound healing processes; however, its role in matrix proteins and diabetic wound healing has not been fully investigated. This review focuses on the role of MMPs in diabetic wound healing and their interaction in PBM.

Bat aggregation mediates the functional structure of ant assemblages.

PubMed

Dejean, Alain; Groc, Sarah; Hérault, Bruno; Rodriguez-Pérez, Héctor; Touchard, Axel; Céréghino, Régis; Delabie, Jacques H C; Corbara, Bruno

2015-10-01

In the Guianese rainforest, we examined the impact of the presence of guano in and around a bat roosting site (a cave). We used ant communities as an indicator to evaluate this impact because they occupy a central place in the functioning of tropical rainforest ecosystems and they play different roles in the food web as they can be herbivores, generalists, scavengers or predators. The ant species richness around the cave did not differ from a control sample situated 500m away. Yet, the comparison of functional groups resulted in significantly greater numbers of detritivorous fungus-growing and predatory ant colonies around the cave compared to the control, the contrary being true for nectar and honeydew feeders. The role of bats, through their guano, was shown using stable isotope analyses as we noted significantly greater δ(15)N values for the ant species captured in and around the cave compared to controls. Copyright © 2015 Académie des sciences. Published by Elsevier SAS. All rights reserved.

Effects of Wind and Freshwater on the Atlantic Meridional Overturning Circulation: Role of Sea Ice and Vertical Diffusion

NASA Astrophysics Data System (ADS)

Wang, Kun; Yang, Haijun; Dai, Haijin; Wang, Yuxing; Li, Qing

2015-04-01

Effects of wind and fresh water on the Atlantic meridional overturning circulation (AMOC) are investigated in a fully coupled climate model (CESM1.0). The AMOC can change significantly when perturbing either the wind stress or fresh water flux in the northern North Atlantic. This work pays special attention on the wind stress effect. Our model results show that the wind forcing is a crucial element in maintaining the AMOC. When the wind-stress is reduced, the vertical convection and diffusion are weakened immediately, triggering a salt deficit in the northern North Atlantic that prevents the deep water formation there. The salinity advection from the south, however, plays a contrary role to salt the upper ocean. As the AMOC weakens, the sea ice expends southward and melts, freshening the upper ocean that weakens the AMOC further. There is a positive feedback between the sea ice melting and AMOC strength, which eventually determines the AMOC strength in the reduced wind world.

Diet and Asthma: Is It Time to Adapt Our Message?

PubMed Central

Scott, Hayley A.

2017-01-01

Asthma is a chronic respiratory disorder which is associated with airway inflammation. Environmental factors, in association with genetic susceptibility, play a critical role in asthma pathophysiology. Inhaled allergens, smoke exposure, indoor and outdoor air pollution are common triggers of asthma symptoms. Although the role of diet has clearly established mechanisms in diseases such as cardiovascular disease, type 2 diabetes, and cancer, it is not commonly identified as a causal factor in asthma. However, some dietary patterns, such as the Western diet, which includes a high intake of refined grains, processed and red meats, and desserts, have pro-inflammatory effects. On the contrary, the Mediterranean diet, with high intake of fruits and vegetables has anti-inflammatory properties. The influence of food on asthma outcomes is of growing interest, but dietary habits of asthma patients are not commonly investigated in clinical practice. In this review, we focus on the impact of diet on asthma risk and asthma control. We also detail the influence of diet on obese patients with asthma. PMID:29117118

SIRT3: Oncogene and Tumor Suppressor in Cancer

PubMed Central

Torrens-Mas, Margalida; Oliver, Jordi; Roca, Pilar; Sastre-Serra, Jorge

2017-01-01

Sirtuin 3 (SIRT3), the major deacetylase in mitochondria, plays a crucial role in modulating oxygen reactive species (ROS) and limiting the oxidative damage in cellular components. SIRT3 targets different enzymes which regulate mitochondrial metabolism and participate in ROS detoxification, such as the complexes of the respiratory chain, the isocitrate dehydrogenase, or the manganese superoxide dismutase. Thus, SIRT3 activity is essential in maintaining mitochondria homeostasis and has recently received great attention, as it is considered a fidelity protein for mitochondrial function. In some types of cancer, SIRT3 functions as a tumoral promoter, since it keeps ROS levels under a certain threshold compatible with cell viability and proliferation. On the contrary, other studies describe SIRT3 as a tumoral suppressor, as SIRT3 could trigger cell death under stress conditions. Thus, SIRT3 could have a dual role in cancer. In this regard, modulation of SIRT3 activity could be a new target to develop more personalized therapies against cancer. PMID:28704962

Genomic islands of divergence are not affected by geography of speciation in sunflowers.

PubMed

Renaut, S; Grassa, C J; Yeaman, S; Moyers, B T; Lai, Z; Kane, N C; Bowers, J E; Burke, J M; Rieseberg, L H

2013-01-01

Genomic studies of speciation often report the presence of highly differentiated genomic regions interspersed within a milieu of weakly diverged loci. The formation of these speciation islands is generally attributed to reduced inter-population gene flow near loci under divergent selection, but few studies have critically evaluated this hypothesis. Here, we report on transcriptome scans among four recently diverged pairs of sunflower (Helianthus) species that vary in the geographical context of speciation. We find that genetic divergence is lower in sympatric and parapatric comparisons, consistent with a role for gene flow in eroding neutral differences. However, genomic islands of divergence are numerous and small in all comparisons, and contrary to expectations, island number and size are not significantly affected by levels of interspecific gene flow. Rather, island formation is strongly associated with reduced recombination rates. Overall, our results indicate that the functional architecture of genomes plays a larger role in shaping genomic divergence than does the geography of speciation.

The Role of the New Zealand Plateau in the Tasman Sea Circulation and Separation of the East Australian Current

NASA Astrophysics Data System (ADS)

Bull, Christopher Y. S.; Kiss, Andrew E.; van Sebille, Erik; Jourdain, Nicolas C.; England, Matthew H.

2018-02-01

The East Australian Current (EAC) plays a major role in regional climate, circulation, and ecosystems, but predicting future changes is hampered by limited understanding of the factors controlling EAC separation. While there has been speculation that the presence of New Zealand may be important for the EAC separation, the prevailing view is that the time-mean partial separation is set by the ocean's response to gradients in the wind stress curl. This study focuses on the role of New Zealand, and the associated adjacent bathymetry, in the partial separation of the EAC and ocean circulation in the Tasman Sea. Here utilizing an eddy-permitting ocean model (NEMO), we find that the complete removal of the New Zealand plateau leads to a smaller fraction of EAC transport heading east and more heading south, with the mean separation latitude shifting >100 km southward. To examine the underlying dynamics, we remove New Zealand with two linear models: the Sverdrup/Godfrey Island Rule and NEMO in linear mode. We find that linear processes and deep bathymetry play a major role in the mean Tasman Front position, whereas nonlinear processes are crucial for the extent of the EAC retroflection. Contrary to past work, we find that meridional gradients in the basin-wide wind stress curl are not the sole factor determining the latitude of EAC separation. We suggest that the Tasman Front location is set by either the maximum meridional gradient in the wind stress curl or the northern tip of New Zealand, whichever is furthest north.

RnlB Antitoxin of the Escherichia coli RnlA-RnlB Toxin-Antitoxin Module Requires RNase HI for Inhibition of RnlA Toxin Activity.

PubMed

Naka, Kenta; Qi, Dan; Yonesaki, Tetsuro; Otsuka, Yuichi

2017-01-11

The Escherichia coli RnlA-RnlB toxin-antitoxin system is related to the anti-phage mechanism. Under normal growth conditions, an RnlA toxin with endoribonuclease activity is inhibited by binding of its cognate RnlB antitoxin. After bacteriophage T4 infection, RnlA is activated by the disappearance of RnlB, resulting in the rapid degradation of T4 mRNAs and consequently no T4 propagation when T4 dmd encoding a phage antitoxin against RnlA is defective. Intriguingly, E. coli RNase HI, which plays a key role in DNA replication, is required for the activation of RnlA and stimulates the RNA cleavage activity of RnlA. Here, we report an additional role of RNase HI in the regulation of RnlA-RnlB system. Both RNase HI and RnlB are associated with NRD (one of three domains of RnlA). The interaction between RnlB and NRD depends on RNase HI. Exogenous expression of RnlA in wild-type cells has no effect on cell growth because of endogenous RnlB and this inhibition of RnlA toxicity requires RNase HI and NRD. These results suggest that RNase HI recruits RnlB to RnlA through NRD for inhibiting RnlA toxicity and thus plays two contrary roles in the regulation of RnlA-RnlB system.

The roles of family, culture, and social cognitive variables in the career interests and goals of Asian American college students.

PubMed

Hui, Kayi; Lent, Robert W

2018-01-01

Although family and cultural factors have been assumed to play important roles in the career development of Asian Americans, theory-driven research on this topic remains limited. We examined culturally relevant factors that may contribute to Asian Americans' consideration of fields in which they are overrepresented (e.g., science, technology, engineering) and underrepresented (e.g., education, social science). Drawing from social cognitive career theory, a culture-specific, social cognitive model of career interests and choice was tested in Holland's (1997) Investigative (I) and Social (S) themes. A sample of 802 Asian American undergraduates completed measures of family support, self-efficacy, outcome expectations, interest, and career choice consideration in relation to both Holland themes. Two indicators of acculturation/enculturation (adherence to Asian values and generation status in the United States) were also obtained. The model accounted for a substantial amount of variance in Asian American college students' career consideration in both themes. Family support and acculturation played varying roles, depending on the Holland theme. For example, family support was linked to career choice consideration both directly (in the S theme) and indirectly, via other predictors (in both themes). Contrary to expectations, the acculturation variables did not moderate the relation of family support or interest to career consideration in either theme. We discuss the implications of these findings for efforts to understand and facilitate the career development of Asian American college students. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

CXCL7 promotes proliferation and invasion of cholangiocarcinoma cells.

PubMed

Guo, Qian; Jian, Zhixiang; Jia, Baoqing; Chang, Liang

2017-02-01

CXCL7 is an important chemoattractant cytokine, which signals through binding to its receptor CXCR2. Recent studies have demonstrated that the CXCL7/CXCR2 signaling plays a promoting role in several common malignancies, including lung, renal, colon, and breast cancer. However, the regulatory role of CXCL7, in cholangiocarcinoma, as well as the underlying mechanism, has not been previously reported. Herein, we found more positive expression of CXCL7 in cholangiocarcinoma tissues compared to adjacent non-tumor tissues. High CXCL7 expression was significantly correlated with poor differentiation, lymph node metastasis, vascular invasion and advanced clinical stage, but was not associated with age, gender, or tumor size. Besides, the expression of CXCL7 was significantly associated with the Ki67 expression, but not associated with CA199, AFP, or P53 expression in cholangiocarcinoma. Moreover, the overall survival of cholangiocarcinoma patients with high CXCL7 expression was significantly shorter than those with low CXCL7 expression. In vitro study indicated that CXCL7 and CXCR2 were also positively expressed in several common cholangiocarcinoma cell lines, including HuCCT1, HuH28, QBC939, EGI-1, OZ and WITT. SiRNA-induced inhibition of CXCL7 significantly reduced the proliferation and invasion of QBC939 cells. On the contrary, overexpression of CXCL7 markedly promoted these malignant phenotypes of QBC939 cells. Of note, the conditioned medium of CXCL7-overexpresing human hepatic stellate cells could also promote the proliferation and invasion of QBC939 cells, suggesting that CXCL7 may also play an oncogenic role in cholangiocarcinoma in a paracrine-dependent manner, not only in an autocrine-dependent manner. Molecular assay data suggested that the AKT signaling pathway was involved in the CXCL7-mediated malignant phenotypes of QBC939 cells. In summary, our study suggests that CXCL7 plays a promoting role in regulating the growth and metastasis of cholangiocarcinoma.

The joint effects of person and situation factors on stress in spaceflight.

PubMed

Endler, Norman S

2004-07-01

Psychologists can play an important role in spaceflight and exploration. Indeed, their input at four specific stages in spaceflight can help to ensure successful missions. Psychologists have a role to play in: 1) Selection; 2) Training; 3) Real or Simulated Space Missions; and 4) Post-Flight Problems. During selection, psychologists can provide guidelines as to the appropriate coping styles for reacting to mission-related stressors. During training, psychologists can help astronauts to plan for, and cope with, problems (e.g., group conflict). Training in social sensitivity, or in specific coping styles (i.e., to be high in task-oriented coping), would be beneficial so that astronauts are able to deal with unforeseen problems. Task-oriented coping is related to control and efficiency, and reduces stress and anxiety. Emotion-oriented coping relates to anxiety for controllable situations, and task-oriented coping is most efficacious. A primary role for psychologists would be the investigation of what problems could arise from living with others in a limited space and for long periods of times. As such, investigations into group dynamics, physical and psychological stress caused by such an environment, and the lack of normal ways to deal with these problems should all be considered. It is also clear that the impact of spaceflight on an individual does not end with physical re-entry. On the contrary, the astronaut will also have to make a psychological post-flight "re-entry" readjustment to life on Earth. Psychologists have an important role to play during all four stages of the space program, especially in regards to person by situation interactions. That is, space is a novel environment for human beings, and we need to investigate how we can better improve the fit between astronauts and space situational stressors. Not only are person by situation interactions relevant for each of the four stages discussed above, but each of the stages interacts with one another bidirectionally and even multidirectionally.

Almost-Quantum Correlations Violate the No-Restriction Hypothesis

NASA Astrophysics Data System (ADS)

Sainz, Ana Belén; Guryanova, Yelena; Acín, Antonio; Navascués, Miguel

2018-05-01

To identify which principles characterize quantum correlations, it is essential to understand in which sense this set of correlations differs from that of almost-quantum correlations. We solve this problem by invoking the so-called no-restriction hypothesis, an explicit and natural axiom in many reconstructions of quantum theory stating that the set of possible measurements is the dual of the set of states. We prove that, contrary to quantum correlations, no generalized probabilistic theory satisfying the no-restriction hypothesis is able to reproduce the set of almost-quantum correlations. Therefore, any theory whose correlations are exactly, or very close to, the almost-quantum correlations necessarily requires a rule limiting the possible measurements. Our results suggest that the no-restriction hypothesis may play a fundamental role in singling out the set of quantum correlations among other nonsignaling ones.

Reevaluating the Sensory Account of Visual Working Memory Storage.

PubMed

Xu, Yaoda

2017-10-01

Recent human fMRI pattern-decoding studies have highlighted the involvement of sensory areas in visual working memory (VWM) tasks and argue for a sensory account of VWM storage. In this review, evidence is examined from human behavior, fMRI decoding, and transcranial magnetic stimulation (TMS) studies, as well as from monkey neurophysiology studies. Contrary to the prevalent view, the available evidence provides little support for the sensory account of VWM storage. Instead, when the ability to resist distraction and the existence of top-down feedback are taken into account, VWM-related activities in sensory areas seem to reflect feedback signals indicative of VWM storage elsewhere in the brain. Collectively, the evidence shows that prefrontal and parietal regions, rather than sensory areas, play more significant roles in VWM storage. Copyright © 2017 Elsevier Ltd. All rights reserved.

Understanding sadomasochism: an empirical examination of four perspectives.

PubMed

Cross, Patricia A; Matheson, Kim

2006-01-01

Three studies assessed current understandings of sadomasochism (SM). In Study 1 questionnaires testing four academic views of SM were administered to individuals who self-defined as involved in SM. The psychoanalytic, psychopathology/medical model, radical feminist and escape-from-self perspectives were not supported. Study 2 examined "virtual" sadomasochism as a source of information about sadomasochists in the real life world. Cluster analyses indicated that real-life and virtual sadomasochists share unique sexual proclivities. Study 3 examined an alternative view that identifies power as the commodity of importance in SM play. Content analysis of online SM encounters indicated that both "top" and "bottom" role-players used several specific techniques to create a power differential. These studies suggest that, contrary to many academic theories, power, and not the giving and receiving of pain, is at the core of SM.

Stress-induced molecules MICA as potential target for radioimmunotherapy of cancer

NASA Astrophysics Data System (ADS)

Abakushina, E. V.; Anokhin, Yu N.; Abakushin, D. N.; Kaprin, A. D.

2017-01-01

Improving the treatment of cancer, increasing their effectiveness and safety is the main objective in the medicine. Molecular nuclear medicine plays an important role in the therapy of cancer. Radioimmunotherapy (RIT) involves the use of antibodies conjugated with therapeutic radionuclides. More often for RIT use the radiolabeled monoclonal antibodies against tumor-associated antigens. Encouraging results have been achieved with this technology in the management of hematologic malignancies. On the contrary, solid tumors have been less responsive. Despite these encouraging results, new potential target for radioimmunodetection and RIT should be found. It was found to increase the level of tumor-associated molecules MICA in the serum of cancer patients. Use of anti-MICA monoclonal antibodies capable a specifically attach to cancer cell via NKG2D ligands and destroy it, is a very promising direction, both therapeutic and diagnostic standpoint.

Dawning of A New Day on Dec. 22, 2012

NASA Image and Video Library

2017-12-08

Dec. 21, 2012 was not the end of the world, contrary to some of the common beliefs out there. NASA's SDO satellite captured this image of the SUN on 12-22-12 at 00:14 UTC as the time rolled over into the new day. To learn more about why the world did not end yesterday, watch this Science @ NASA video: youtu.be/2wimiRUHMI4 or visit www.nasa.gov/2012 Credit: NASA/NOAA GOES Project NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

Community structure in traffic zones based on travel demand

NASA Astrophysics Data System (ADS)

Sun, Li; Ling, Ximan; He, Kun; Tan, Qian

2016-09-01

Large structure in complex networks can be studied by dividing it into communities or modules. Urban traffic system is one of the most critical infrastructures. It can be abstracted into a complex network composed of tightly connected groups. Here, we analyze community structure in urban traffic zones based on the community detection method in network science. Spectral algorithm using the eigenvectors of matrices is employed. Our empirical results indicate that the traffic communities are variant with the travel demand distribution, since in the morning the majority of the passengers are traveling from home to work and in the evening they are traveling a contrary direction. Meanwhile, the origin-destination pairs with large number of trips play a significant role in urban traffic network's community division. The layout of traffic community in a city also depends on the residents' trajectories.

Differential expression of homeobox-containing genes Msx-1 and Msx-2 and homeoprotein Msx-2 expression during chick craniofacial development.

PubMed

Nishikawa, K; Nakanishi, T; Aoki, C; Hattori, T; Takahashi, K; Taniguchi, S

1994-03-01

The expression pattern of chick Msx-1 and Msx-2 homeobox genes in craniofacial primordia was examined by in situ hybridization using cRNA probes. Both genes were expressed in the distal region of the facial primordia, where the distribution of Msx-2 expression was restricted distally within the Msx-1 expression domain. On the contrary, Msx-2 expression in the lateral choroid plexus and cranial skull was broader and more intensive than Msx-1 expression. Our findings suggest that these two genes cooperate to play differential roles in craniofacial development. Msx-2 protein was detected immunohistochemically, and its localization essentially corresponded to the mRNA expression pattern, substantiating the involvement of Msx-2 protein as a transcriptional regulator in developing limb and face.

A general mechanism for competitor-induced dissociation of molecular complexes

PubMed Central

Paramanathan, Thayaparan; Reeves, Daniel; Friedman, Larry J.; Kondev, Jane; Gelles, Jeff

2014-01-01

The kinetic stability of non-covalent macromolecular complexes controls many biological phenomena. Here we find that physical models of complex dissociation predict that competitor molecules will in general accelerate the breakdown of isolated bimolecular complexes by occluding rapid rebinding of the two binding partners. This prediction is largely independent of molecular details. We confirm the prediction with single-molecule fluorescence experiments on a well-characterized DNA strand dissociation reaction. Contrary to common assumptions, competitor–induced acceleration of dissociation can occur in biologically relevant competitor concentration ranges and does not necessarily implyternary association of competitor with the bimolecular complex. Thus, occlusion of complex rebinding may play a significant role in a variety of biomolecular processes. The results also show that single-molecule colocalization experiments can accurately measure dissociation rates despite their limited spatio temporal resolution. PMID:25342513

Figure-Ground Processing: A Reassessment of Gelb and Granit.

PubMed

Nelson, Rolf; Hebda, Nicholas

2018-03-01

In 1923, Adhemar Gelb and Ragnar Granit, two prominent researchers in early Gestalt perceptual theory, reported a lower threshold for detection of a target (a small colored dot) on the ground region of an image than on an adjacent figural region. Although their results had a wide influence on the understanding of figure-ground perception, they are at odds with more recent investigations in which figural regions appear to have a processing advantage over ground regions. The two present studies replicated Gelb and Granit's experiment using a similar figure-ground stimulus albeit with a two-alternative forced choice procedure rather than their original method of adjustment. Experiment 1 found that, contrary to Gelb and Granit's findings, a detection advantage was found for the figural over the ground region. Experiment 2 indicated that explicit contours might have played a role in detection.

Almost-Quantum Correlations Violate the No-Restriction Hypothesis.

PubMed

Sainz, Ana Belén; Guryanova, Yelena; Acín, Antonio; Navascués, Miguel

2018-05-18

To identify which principles characterize quantum correlations, it is essential to understand in which sense this set of correlations differs from that of almost-quantum correlations. We solve this problem by invoking the so-called no-restriction hypothesis, an explicit and natural axiom in many reconstructions of quantum theory stating that the set of possible measurements is the dual of the set of states. We prove that, contrary to quantum correlations, no generalized probabilistic theory satisfying the no-restriction hypothesis is able to reproduce the set of almost-quantum correlations. Therefore, any theory whose correlations are exactly, or very close to, the almost-quantum correlations necessarily requires a rule limiting the possible measurements. Our results suggest that the no-restriction hypothesis may play a fundamental role in singling out the set of quantum correlations among other nonsignaling ones.

Mutation induction by heavy ions

NASA Astrophysics Data System (ADS)

Kiefer, J.; Stoll, U.; Schneider, E.

1994-10-01

Mutation induction by heavy ions is compared in yeast and mammalian cells. Since mutants can only be recovered in survivors the influence of inactivation cross sections has to be taken into account. It is shown that both the size of the sensitive cellular site as well as track structure play an important role. Another parameter which influences the probability of mutation induction is repair: Contrary to naive assumptions primary radiation damage does not directly lead to mutations but requires modification to reconstitute the genetic machinery so that mutants can survive. The molecular structure of mutations was analyzed after exposure to deuterons by amplification with the aid of polymerase chain reaction. The results-although preliminary-demonstrate that even with densely ionizing particles a large fraction does not carry big deletions which suggests that point mutations may also be induced by heavy ions.

Aqueous sodium borohydride induced thermally stable porous zirconium oxide for quick removal of lead ions

PubMed Central

Nayak, Nadiya B.; Nayak, Bibhuti B.

2016-01-01

Aqueous sodium borohydride (NaBH4) is well known for its reducing property and well-established for the development of metal nanoparticles through reduction method. In contrary, this research paper discloses the importance of aqueous NaBH4 as a precipitating agent towards development of porous zirconium oxide. The boron species present in aqueous NaBH4 play an active role during gelation as well as phase separated out in the form of boron complex during precipitation, which helps to form boron free zirconium hydroxide [Zr(OH)4] in the as-synthesized condition. Evolved in-situ hydrogen (H2) gas-bubbles also play an important role to develop as-synthesized loose zirconium hydroxide and the presence of intra-particle voids in the loose zirconium hydroxide help to develop porous zirconium oxide during calcination process. Without any surface modification, this porous zirconium oxide quickly adsorbs almost hundred percentages of toxic lead ions from water solution within 15 minutes at normal pH condition. Adsorption kinetic models suggest that the adsorption process was surface reaction controlled chemisorption. Quick adsorption was governed by surface diffusion process and the adsorption kinetic was limited by pore diffusion. Five cycles of adsorption-desorption result suggests that the porous zirconium oxide can be reused efficiently for removal of Pb (II) ions from aqueous solution. PMID:26980545

Presenting health risk information in different formats: the effect on participants' cognitive and emotional evaluation and decisions.

PubMed

Timmermans, Daniëlle R M; Ockhuysen-Vermey, Caroline F; Henneman, Lidewij

2008-12-01

Effective communication of health risks plays an important role in enabling patients to make adequate decisions. There is little--though contradictory--evidence to indicate which format is most effective for communicating risks, and which risk format is preferred by counselees. In an experiment, subjects were presented health scenarios and risk information in different formats (percentages, frequencies, and population figures) and asked to evaluate the risks and make a decision based on these. Different risk formats had different effects on respondents' evaluation of the health risks presented. Contrary to our expectation, population figures were not evaluated as being the easiest format for all decision problems. Population figures were shown to have the biggest affective impact, and risks presented as population figures were also evaluated as significantly greater than the risks presented in other formats. The format of the presented risks influenced their decision in only one out of four decision-making situations, although in a second situation there was a similar trend. This study suggests that the risk format plays a role in the decision-making process, although it remains unclear which format is the most effective in terms of understanding. More experimental studies based on a theoretical analysis of the factors that promote effective risk communication are needed in the general population as well as in clinical settings with patients actually experiencing the risks and making the decisions.

Morphology-controlled synthesis of Co{sub 3}O{sub 4} by one step template-free hydrothermal method

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

Zhou, Keqing; Liu, Jiajia; Wen, Panyue

2015-07-15

Highlights: • Co{sub 3}O{sub 4} crystals had been synthesized by one step template-free hydrothermal method. • The H{sub 2}O{sub 2} plays a crucial role in morphological control of Co{sub 3}O{sub 4} nanostructures. • The morphology has significant effect on the optical property of Co{sub 3}O{sub 4}. - Abstract: We had developed a facile synthetic route of Co{sub 3}O{sub 4} crystals with different morphologies via one step template-free hydrothermal method. The phase and composition of the Co{sub 3}O{sub 4} were investigated by X-ray powder diffraction and Raman spectrum. The morphology and structure of the synthesized samples were characterized by scanning electronmore » microscopy and transmission electron microscopy. The H{sub 2}O{sub 2} played a crucial role in morphological control of Co{sub 3}O{sub 4} nanostructures. It only obtained Co-based precursor in the absence of H{sub 2}O{sub 2}. On the contrary, the Co{sub 3}O{sub 4} with different morphologies including nanoparticles, nano-discs and well-defined octahedral nanostructures were synthesized in the presence of H{sub 2}O{sub 2}. In addition, the optical property of the obtained Co{sub 3}O{sub 4} samples was investigated by UV–vis spectra.« less

Impacts of Climate Change on Forest Isoprene Emission: Diversity Matters

NASA Astrophysics Data System (ADS)

Wang, B.; Shugart, H. H., Jr.; Lerdau, M.

2016-12-01

Many abiotic and biotic factors influence volatile organic compound (VOC) production and emission by plants; for example, climate warming is widely projected to enhance VOC emissions by stimulating their biosynthesis. The species-dependent nature of VOC production by plants indicates that changes in species abundances may play an important role in determining VOC production and emission at the ecosystem scale. To date, however, the role of species abundances in affecting VOC emissions has not been well studied. We examine the role of forest systems as sources of VOC's in terms of how species diversity and abundance influence isoprene emission under climate warming by using an individual-based forest VOC emission model—UVAFME-VOC 1.0—that can explicitly simulate forest compositional and structural change and VOC production/emission at the individual and canopy scales. We simulate isoprene emissions under two warming scenarios (warming by 2 and 4 °C) for temperate deciduous forests of the southeastern United States, where the dominant isoprene-emitting species are oaks (Quercus). The simulations show that, contrary to previous expectations, a warming by 2 °C does not affect isoprene emissions, while a further warming by 4 °C causes a large reduction of isoprene emissions. Interestingly, climate warming can directly enhance isoprene emission and simultaneously indirectly reduce it by lowering the abundance of isoprene-emitting species. Under gradual continuous warming, the indirect effect outweighs the direct effect, thus reducing overall forest isoprene emission. This modelling study shows that climate warming does not necessarily stimulate ecosystem VOC emissions and, more generally, that ecosystem diversity and composition can play a significant role in determining vegetation VOC emission capacity. Future earth system models and climate-chemistry models should better represent species diversity in projecting climate-air quality feedbacks and making management policy recommendations.

Facial expressions as a model to test the role of the sensorimotor system in the visual perception of the actions.

PubMed

Mele, Sonia; Ghirardi, Valentina; Craighero, Laila

2017-12-01

A long-term debate concerns whether the sensorimotor coding carried out during transitive actions observation reflects the low-level movement implementation details or the movement goals. On the contrary, phonemes and emotional facial expressions are intransitive actions that do not fall into this debate. The investigation of phonemes discrimination has proven to be a good model to demonstrate that the sensorimotor system plays a role in understanding actions acoustically presented. In the present study, we adapted the experimental paradigms already used in phonemes discrimination during face posture manipulation, to the discrimination of emotional facial expressions. We submitted participants to a lower or to an upper face posture manipulation during the execution of a four alternative labelling task of pictures randomly taken from four morphed continua between two emotional facial expressions. The results showed that the implementation of low-level movement details influence the discrimination of ambiguous facial expressions differing for a specific involvement of those movement details. These findings indicate that facial expressions discrimination is a good model to test the role of the sensorimotor system in the perception of actions visually presented.

Molecular dynamics simulations reveal a new role for a conserved active site asparagine in a ubiquitin-conjugating enzyme.

PubMed

Wilson, R Hunter; Zamfir, Serban; Sumner, Isaiah

2017-09-01

The role of a highly conserved active site asparagine (N79) in the ubiquitin conjugating enzyme, Ubc13, is probed using molecular dynamics simulations. Both wild type and mutant enzymes (N79A and N79D) are studied. Contrary to a popular hypothesis, we show that it is unlikely that N79 stabilizes a reaction intermediate, but instead preferentially hydrogen bonds to a loop near the active site. This keeps the sidechain carboxylate of an aspartate in the loop (D119) near the sidechain amine of the substrate lysine. Our simulations show that this distance increases in the mutants. D119 has been hypothesized to play a variety of roles in the enzyme, including deprotonating the substrate lysine, so changing this distance can have an effect on the enzyme's efficiency. Finally, we show that it is possible for the aspartate to deprotonate the substrate even across long distances if short water wires form that connect the proton donor and acceptor. Short water wires form with greater probability in the wild type than in mutant enzymes. Copyright © 2017 Elsevier Inc. All rights reserved.

Major histocompatibility complex similarity and sexual selection: different does not always mean attractive.

PubMed

Gasparini, Clelia; Congiu, Leonardo; Pilastro, Andrea

2015-08-01

Females that mate multiply have the possibility to exert postcopulatory choice and select more compatible sperm to fertilize eggs. Prior work suggests that dissimilarity in major histocompatibility complex (MHC) plays an important role in determining genetic compatibility between partners. Favouring a partner with dissimilar MHC alleles would result in offspring with high MHC diversity and therefore with enhanced survival thanks to increased resistance to pathogens and parasites. The high variability of MHC genes may further allow discrimination against the sperm from related males, reducing offspring homozygosity and inbreeding risk. Despite the large body of work conducted at precopulatory level, the role of MHC similarity between partners at postcopulatory level has been rarely investigated. We used an internal fertilizing fish with high level of multiple matings (Poecilia reticulata) to study whether MHC similarity plays a role in determining the outcome of fertilization when sperm from two males compete for the same set of eggs. We also controlled for genomewide similarity by determining similarity at 10 microsatellite loci. Contrary to prediction, we found that the more MHC-similar male sired more offspring while similarity at the microsatellite loci did not predict the outcome of sperm competition. Our results suggest that MHC discrimination may be involved in avoidance of hybridization or outbreeding rather than inbreeding avoidance. This, coupled with similar findings in salmon, suggests that the preference for MHC-dissimilar mates is far from being unanimous and that pre- and postcopulatory episodes of sexual selection can indeed act in opposite directions. © 2015 John Wiley & Sons Ltd.

Oxidation of Са2+-Binding Domain of NADPH Oxidase 5 (NOX5): Toward Understanding the Mechanism of Inactivation of NOX5 by ROS.

PubMed

Petrushanko, Irina Yu; Lobachev, Vladimir M; Kononikhin, Alexey S; Makarov, Alexander A; Devred, Francois; Kovacic, Hervé; Kubatiev, Aslan A; Tsvetkov, Philipp O

2016-01-01

NOX5 protein, one of the most active generators of reactive oxygen species (ROS), plays an important role in many processes, including regulation of cell growth, death and differentiation. Because of its central role in ROS generation, it needs to be tightly regulated to guarantee cellular homeostasis. Contrary to other members of NADPH-oxidases family, NOX5 has its own regulatory calcium-binding domain and thus could be activated directly by calcium ions. While several mechanisms of activation have been described, very little is known about the mechanisms that could prevent the overproduction of ROS by NOX5. In the present study using calorimetric methods and circular dichroism we found that oxidation of cysteine and methionine residues of NOX5 decreases binding of Ca2+ ions and perturbs both secondary and tertiary structure of protein. Our data strongly suggest that oxidation of calcium-binding domain of NOX5 could be implicated in its inactivation, serving as a possible defense mechanism against oxidative stress.

A major role of DNA polymerase δ in replication of both the leading and lagging DNA strands

PubMed Central

Prakash, Louise; Prakash, Satya

2015-01-01

SUMMARY Genetic studies with S. cerevisiae Polδ (pol3-L612M) and Polε (pol2-M644G) mutant alleles, each of which display a higher rate for the generation of a specific mismatch, have led to the conclusion that Polε is the primary leading strand replicase and that Polδ is restricted to replicating the lagging strand template. Contrary to this widely accepted view, here we show that Polδ plays a major role in the replication of both DNA strands, and that the paucity of pol3-L612M generated errors on the leading strand results from their more proficient removal. Thus, the apparent lack of Polδ contribution to leading strand replication is due to differential mismatch removal rather than differential mismatch generation. Altogether, our genetic studies with Pol3 and Pol2 mutator alleles support the conclusion that Polδ, and not Polε, is the major DNA polymerase for carrying out both leading and lagging DNA synthesis. PMID:26145172

JMJD3 inhibition protects against isoproterenol-induced cardiac hypertrophy by suppressing β-MHC expression.

PubMed

Guo, Zhen; Lu, Jing; Li, Jingyan; Wang, Panxia; Li, Zhenzhen; Zhong, Yao; Guo, Kaiteng; Wang, Junjian; Ye, Jiantao; Liu, Peiqing

2018-05-10

Jumonji domain-containing protein D3 (JMJD3), a histone 3 lysine 27 (H3K27) demethylase, has been extensively studied for their participation in development, cellular physiology and a variety of diseases. However, its potential roles in cardiovascular system remain unknown. In this study, we found that JMJD3 played a pivotal role in the process of cardiac hypertrophy. JMJD3 expression was elevated by isoproterenol (ISO) stimuli both in vitro and in vivo. Overexpression of wild-type JMJD3, but not the demethylase-defective mutant, promoted cardiomyocyte hypertrophy, as implied by increased cardiomyocyte surface area and the expression of hypertrophy marker genes. In contrary, JMJD3 silencing or its inhibitor GSK-J4 suppressed ISO-induced cardiac hypertrophy. Mechanistically, JMJD3 was recruited to demethylate H3K27me3 at the promoter of β-MHC to promote its expression and cardiac hypertrophy. Thus, our results reveal that JMJD3 may be a key epigenetic regulator of β-MHC expression in cardiomyocytes and a potential therapeutic target for cardiac hypertrophy. Copyright © 2018. Published by Elsevier B.V.

Men's Perceptions of an Acquaintance Rape: The Role of Relationship Length, Victim Resistance, and Gender Role Attitudes.

PubMed

Angelone, D J; Mitchell, Damon; Grossi, Laura

2015-08-01

Sexual aggression is a persistent and prevalent issue in the United States, which often results in a number of psychological, emotional, and physical consequences for victims. The current study examined whether the length of relationship between the victim and perpetrator, level of victim resistance, and observers' gender role attitudes play a role in observers' perceptions of an alleged sexual assault. Participants included 297 male college students from a public university in the Northeastern United States. Contrary to hypotheses, there were no significant effects for length of relationship on participants' attributions. Relative to no resistance, verbal and physical strategies by the victim predicted higher levels of victim credibility, perpetrator culpability, and perpetrator guilt, as well as lower levels of victim culpability and perceived victim pleasure. Endorsement of traditional adversarial sex role beliefs and hostile sexist attitudes, as opposed to egalitarian attitudes, were associated with the attribution of less credibility to the victim, perceived victim trauma, perpetrator culpability, perpetrator guilt, and shorter recommended prison sentences, as well as greater victim culpability and perceived victim pleasure. Laypersons' perceptions of sexual assault merit further study, as they are relevant to juror decision making and third party responses to sexual victimization (e.g., peer support for victim) and can contribute to the secondary victimization and recovery of survivors of sexual assault. © The Author(s) 2014.

[Good ending and better beginning. What future for medical journals?].

PubMed

De Fiore, Luca

2015-12-01

Scientific journals play an increasingly important role in the dissemination of research results, but also in the adoption of pharmaceutical innovation and technology in medicine. Healthcare decision makers are strongly influenced by the academic literature and for this reason medical journals should retain their independence and autonomy, preventing conflicts of interest. In a recently published editorial, the editor of the New England Journal of Medicine seems to be pleased with the results achieved. On the contrary, according to the editor of a respected specialized cardiovascular journal, Harlan Krumholz, journals are facing a number of important challenges. Medical journals are too expensive, too limited, too unreliable, too focused on wrong metrics, too powerful, too parochial, too static, and too dependent on a distorted model of business. In conclusion, medical journals do not seem to be the most appropriate educational tool in a scientific context that assigns value to transparency and sharing.

How does race get "under the skin"?: inflammation, weathering, and metabolic problems in late life.

PubMed

Das, Aniruddha

2013-01-01

Using nationally representative data from the 2005-2006 U.S. National Social Life, Health, and Aging Project, this study queries the mechanisms underlying worse metabolic outcomes--blood-sugar control and cardiovascular health--among black than white men ages 57-85. Results indicate that contrary to much of the academic literature as well as media accounts-implicitly rooted in a "culture of irresponsibility" model--older black men's social isolation, poor health behaviors, or obesity may not play a major role in their worse metabolic problems. Instead, these outcomes seem to derive more consistently from a factor almost unexamined in the literature--chronic inflammation, arguably a biological "weathering" mechanism induced by these men's cumulative and multi-dimensional stress. These findings highlight the necessity of focusing attention not simply on proximal behavioral interventions, but on broader stress-inducing social inequalities, to reduce men's race disparities in health. Copyright © 2012 Elsevier Ltd. All rights reserved.

Sequence-dependent nucleosome sliding in rotation-coupled and uncoupled modes revealed by molecular simulations

PubMed Central

Tan, Cheng; Takada, Shoji

2017-01-01

While nucleosome positioning on eukaryotic genome play important roles for genetic regulation, molecular mechanisms of nucleosome positioning and sliding along DNA are not well understood. Here we investigated thermally-activated spontaneous nucleosome sliding mechanisms developing and applying a coarse-grained molecular simulation method that incorporates both long-range electrostatic and short-range hydrogen-bond interactions between histone octamer and DNA. The simulations revealed two distinct sliding modes depending on the nucleosomal DNA sequence. A uniform DNA sequence showed frequent sliding with one base pair step in a rotation-coupled manner, akin to screw-like motions. On the contrary, a strong positioning sequence, the so-called 601 sequence, exhibits rare, abrupt transitions of five and ten base pair steps without rotation. Moreover, we evaluated the importance of hydrogen bond interactions on the sliding mode, finding that strong and weak bonds favor respectively the rotation-coupled and -uncoupled sliding movements. PMID:29194442

Numeracy moderates the influence of task-irrelevant affect on probability weighting.

PubMed

Traczyk, Jakub; Fulawka, Kamil

2016-06-01

Statistical numeracy, defined as the ability to understand and process statistical and probability information, plays a significant role in superior decision making. However, recent research has demonstrated that statistical numeracy goes beyond simple comprehension of numbers and mathematical operations. On the contrary to previous studies that were focused on emotions integral to risky prospects, we hypothesized that highly numerate individuals would exhibit more linear probability weighting because they would be less biased by incidental and decision-irrelevant affect. Participants were instructed to make a series of insurance decisions preceded by negative (i.e., fear-inducing) or neutral stimuli. We found that incidental negative affect increased the curvature of the probability weighting function (PWF). Interestingly, this effect was significant only for less numerate individuals, while probability weighting in more numerate people was not altered by decision-irrelevant affect. We propose two candidate mechanisms for the observed effect. Copyright © 2016 Elsevier B.V. All rights reserved.

Conscious Action/Zombie Action

PubMed Central

Shepherd, Joshua

2015-01-01

Abstract I argue that the neural realizers of experiences of trying (that is, experiences of directing effort towards the satisfaction of an intention) are not distinct from the neural realizers of actual trying (that is, actual effort directed towards the satisfaction of an intention). I then ask how experiences of trying might relate to the perceptual experiences one has while acting. First, I assess recent zombie action arguments regarding conscious visual experience, and I argue that contrary to what some have claimed, conscious visual experience plays a causal role for action control in some circumstances. Second, I propose a multimodal account of the experience of acting. According to this account, the experience of acting is (at the very least) a temporally extended, co‐conscious collection of agentive and perceptual experiences, functionally integrated and structured both by multimodal perceptual processing as well as by what an agent is, at the time, trying to do. PMID:27667859

Evidence of a Structural Defect in Ice VII and the Side Chain Dependent Response of Small Model Peptides to Increased Pressure

PubMed Central

Scott, J. Nathan; Vanderkooi, Jane M.

2014-01-01

The effect of high pressure on the OH stretch of dilute HOD in D2O was examined using high pressure FTIR. It was found that at pressures directly above the ice VI to ice VII transition, ice VII displays a splitting in the OH absorption indicative of differing hydrogen bonding environments. This result is contrary to published structures of ice VII in which each OH oscillator should experience an identical electronic environment. The anomalous band was found to decrease in absorbance and finally disappear at ~43.0 kbar. In addition, the pressure response of the amide I′ and II′ bands of three small model peptides was examined. Analysis of these bands’ response to increased pressure indicates significant side chain dependence of their structural rearrangement, which may play a role in the composition of full length proteins of barophilic organisms. PMID:21740637

My Pride and Joy? Predicting Favoritism and Disfavoritism in Mother-Adult Child Relations.

PubMed

Suitor, J Jill; Gilligan, Megan; Peng, Siyun; Con, Gulcin; Rurka, Marissa; Pillemer, Karl

2016-08-01

In this article, we compare predictors of mothers' differentiation among their adult children regarding emotional closeness, pride, conflict, and disappointment. We distinguish between predictors of relational (closeness, conflict) and evaluative (pride, disappointment) dimensions of favoritism and disfavoritism. Multilevel modeling using data collected from 381 older mothers regarding their relationships with 1,421 adult children indicated that adult children's similarity of values played the most prominent role in predicting mothers' favoritism and disfavoritism, followed by children's gender. Children's deviant behaviors in adulthood predicted both pride and disappointment but neither relational dimension. Contrary to expectations, the quantitative analysis indicated that children's normative adult achievements were poor predictors of both relational and evaluative dimensions of mothers' differentiation. Qualitative data shed additional light on mothers' evaluations by revealing that disappointment was shaped by children's achievements relative to their mothers' values and expectations, rather than by the achievement of specific societal, educational, career, and marital milestones.

Ordered water structure at hydrophobic graphite interfaces observed by 4D, ultrafast electron crystallography

PubMed Central

Yang, Ding-Shyue; Zewail, Ahmed H.

2009-01-01

Interfacial water has unique properties in various functions. Here, using 4-dimensional (4D), ultrafast electron crystallography with atomic-scale spatial and temporal resolution, we report study of structure and dynamics of interfacial water assembly on a hydrophobic surface. Structurally, vertically stacked bilayers on highly oriented pyrolytic graphite surface were determined to be ordered, contrary to the expectation that the strong hydrogen bonding of water on hydrophobic surfaces would dominate with suppressed interfacial order. Because of its terrace morphology, graphite plays the role of a template. The dynamics is also surprising. After the excitation of graphite by an ultrafast infrared pulse, the interfacial ice structure undergoes nonequilibrium “phase transformation” identified in the hydrogen-bond network through the observation of structural isosbestic point. We provide the time scales involved, the nature of ice-graphite structural dynamics, and relevance to properties related to confined water. PMID:19246378

[Clinical trials in developing countries: who should define ethics?].

PubMed

Béréterbide, F; Hirsch, F

2008-04-01

Many clinical trials have proved much more difficult to implement in developing countries than in the Northern countries if not totally impossible. Should we therefore just observe this situation and approve a "double ethical standard"? Clinical trials in developing countries are also a means for volunteers to have access to medical care, therefore how could the process of informed consent keep its significance? In this context, should the participation in clinical trials be restricted or even stopped? If so, we would thus justify the superiority of an international duty of charity compared with the right of autonomy of these populations. This theoretical analysis cannot be precisely justified. On the contrary, it reveals that while informed consent, international organisations and guidelines have the tendency to play a major role in this debate, local ethics committee are too absent although they represent the more relevant and legitimate discussion partners in this dilemma.

Retromer association with membranes: plants have their own rules!

PubMed

Zelazny, Enric; Santambrogio, Martina; Gaude, Thierry

2013-09-01

The retromer is an endosome-localized complex involved in protein trafficking. To better understand its function and regulation in plants, we recently investigated how Arabidopsis retromer subunits assemble and are targeted to endosomal membranes and highlighted original features compared with mammals. We characterized Arabidopsis vps26 null mutant and showed that it displays severe developmental defaults similar to those observed in vps29 mutant. Here, we go further by describing new phenotypic defects associated with loss of VPS26 function, such as inhibition of lateral root initiation. Recently, we showed that VPS35 subunit plays a crucial role in the recruitment of the plant retromer to endosomes, probably through an interaction with the Rab7 homolog RABG3f. In this work, we now show that contrary to mammals, Arabidopsis Rab5 homologs do not seem to be necessary for the recruitment of the core retromer to endosomal membranes, which highlights a new specificity of the plant retromer.

Discovery of a photoresponse amplification mechanism in compensated PN junctions

NASA Astrophysics Data System (ADS)

Zhou, Yuchun; Liu, Yu-Hsin; Rahman, Samia N.; Hall, David; Sham, L. J.; Lo, Yu-Hwa

2015-01-01

We report the experimental evidence of uncovering a photoresponse amplification mechanism in heavily doped, partially compensated silicon p-n junctions under very low bias voltage. We show that the observed photocurrent gain occurs at a bias that is more than an order of magnitude below the threshold voltage for conventional impact ionization. Moreover, contrary to the case of avalanche detectors and p-i-n diodes, the amplified photoresponse is enhanced rather than suppressed with increasing temperature. These distinctive characteristics lead us to hypothesize that the inelastic scattering between energetic electrons (holes) and the ionized impurities in the depletion and charge neutral regions of the p-n junction in a cyclic manner plays a significant role in the amplification process. Such an internal signal amplification mechanism, which occurs at much lower bias than impact ionization and favors room temperature over cryogenic temperature, makes it promising for practical device applications.

Higgs data does not rule out a sequential fourth generation with an extended scalar sector

NASA Astrophysics Data System (ADS)

Das, Dipankar; Kundu, Anirban; Saha, Ipsita

2018-01-01

Contrary to common perception, we show that the current Higgs data does not eliminate the possibility of a sequential fourth generation that get their masses through the same Higgs mechanism as the first three generations. The inability to fix the sign of the bottom-quark Yukawa coupling from the available data plays a crucial role in accommodating a chiral fourth generation which is consistent with the bounds on the Higgs signal strengths. We show that effects of such a fourth generation can remain completely hidden not only in the production of the Higgs boson through gluon fusion but also to its subsequent decay to γ γ and Z γ . This, however, is feasible only if the scalar sector of the standard model is extended. We also provide a practical example illustrating how our general prescription can be embedded in a realistic model.

Serrated pathway: Alternative route to colorectal cancer

PubMed Central

Patai, Árpád V; Molnár, Béla; Tulassay, Zsolt; Sipos, Ferenc

2013-01-01

Serrated polyps have been an area of intense focus for gastroenterologists over the past several years. Contrary to what was thought before, a growing body of literature indicates that these polyps can be precursors of colorectal cancer (CRC). Most of these lesions, particularly those in the proximal colon, have so far been under-recognized and missed during colonoscopy, qualifying these lesions to be the main cause of interval cancers. It is estimated that 10%-20% of CRCs evolve through this alternative, serrated pathway, with a distinct genetic and epigenetic profile. Aberrant DNA methylation plays a central role in the development of this CRC subtype. This characteristic molecular background is reflected in a unique pathological and clinical manifestation different from cancers arising via the traditional pathway. In this review we would like to highlight morphological, molecular and clinical features of this emerging pathway that are essential for gastroenterologists and may influence their everyday practice. PMID:23431044

Intention Seekers: Conspiracist Ideation and Biased Attributions of Intentionality

PubMed Central

2015-01-01

Conspiracist beliefs are widespread and potentially hazardous. A growing body of research suggests that cognitive biases may play a role in endorsement of conspiracy theories. The current research examines the novel hypothesis that individuals who are biased towards inferring intentional explanations for ambiguous actions are more likely to endorse conspiracy theories, which portray events as the exclusive product of intentional agency. Study 1 replicated a previously observed relationship between conspiracist ideation and individual differences in anthropomorphisation. Studies 2 and 3 report a relationship between conspiracism and inferences of intentionality for imagined ambiguous events. Additionally, Study 3 again found conspiracist ideation to be predicted by individual differences in anthropomorphism. Contrary to expectations, however, the relationship was not mediated by the intentionality bias. The findings are discussed in terms of a domain-general intentionality bias making conspiracy theories appear particularly plausible. Alternative explanations are suggested for the association between conspiracism and anthropomorphism. PMID:25970175

Deformation behavior of human dentin in liquid nitrogen: a diametral compression test.

PubMed

Zaytsev, Dmitry; Panfilov, Peter

2014-09-01

Contribution of the collagen fibers into the plasticity of human dentin is considered. Mechanical testing of dentin at low temperature allows excluding the plastic response of its organic matrix. Therefore, deformation and fracture behavior of the dentin samples under diametral compression at room temperature and liquid nitrogen temperature are compared. At 77K dentin behaves like almost brittle material: it is deformed exclusively in the elastic regime and it fails due to growth of the sole crack. On the contrary, dentin demonstrates the ductile response at 300K. There are both elastic and plastic contributions in the deformation of dentin samples. Multiple cracking and crack tip blunting precede the failure of samples. Organic phase plays an important role in fracture of dentin: plasticity of the collagen fibers could inhibit the crack growth. Copyright © 2014 Elsevier B.V. All rights reserved.

The properties of the anti-tumor model with coupling non-Gaussian noise and Gaussian colored noise

NASA Astrophysics Data System (ADS)

Guo, Qin; Sun, Zhongkui; Xu, Wei

2016-05-01

The anti-tumor model with correlation between multiplicative non-Gaussian noise and additive Gaussian-colored noise has been investigated in this paper. The behaviors of the stationary probability distribution demonstrate that the multiplicative non-Gaussian noise plays a dual role in the development of tumor and an appropriate additive Gaussian colored noise can lead to a minimum of the mean value of tumor cell population. The mean first passage time is calculated to quantify the effects of noises on the transition time of tumors between the stable states. An increase in both the non-Gaussian noise intensity and the departure from the Gaussian noise can accelerate the transition from the disease state to the healthy state. On the contrary, an increase in cross-correlated degree will slow down the transition. Moreover, the correlation time can enhance the stability of the disease state.

[Showing skin (or not) on the hot Tunisian sand: an impossible version of Sea, Sex and Sun?].

PubMed

Héas, Stéphane; Héas, Corinne

2011-01-01

Beaches are places where human behavior is highly codified. The revealing or on the contrary concealing of one's body responds to complex cultural imperatives. Exposure of skin is never trivial, or harmless from a health point of view, and it always has repercussions in terms of social relations. This article is based on direct observations over several years in a small coastal town in Tunisia. The presentation of the body is described in particular with regard to the wearing of veils and in terms of relationships between men and women. Contact with water or sand and sun exposure play a role in the system of exchange of gestures observed. The strategies they use are presented in terms of the concept of social pollution and according to the beaches that distinguish between the different types of beachgoers.

Behavioral and brain asymmetries in primates: a preliminary evaluation of two evolutionary hypotheses

PubMed Central

Hopkins, William D.; Misiura, Maria; Pope, Sarah M.; Latash, Elitaveta M.

2015-01-01

Contrary to many historical views, recent evidence suggest that species-level behavioral and brain asymmetries are evident in nonhuman species. Here, we briefly present evidence of behavioral, perceptual, cognitive, functional, and neuroanatomical asymmetries in nonhuman primates. In addition, we describe two historical accounts of the evolutionary origins of hemispheric specialization and present data from nonhuman primates that address these specific theories. Specifically, we first discuss the evidence of that genes play specific roles in determining left–right differences in anatomical and functional asymmetries in primates. We next consider and present data on the hypothesis that hemispheric specialization evolved as a by-product of increasing brain size relative to the size of the corpus callosum in different primate species. Lastly, we discuss some of the challenges in the study of hemispheric specialization in primates and offer some suggestions on how to advance the field. PMID:26426409

Behavioral and brain asymmetries in primates: a preliminary evaluation of two evolutionary hypotheses.

PubMed

Hopkins, William D; Misiura, Maria; Pope, Sarah M; Latash, Elitaveta M

2015-11-01

Contrary to many historical views, recent evidence suggests that species-level behavioral and brain asymmetries are evident in nonhuman species. Here, we briefly present evidence of behavioral, perceptual, cognitive, functional, and neuroanatomical asymmetries in nonhuman primates. In addition, we describe two historical accounts of the evolutionary origins of hemispheric specialization and present data from nonhuman primates that address these specific theories. Specifically, we first discuss the evidence that genes play specific roles in determining left-right differences in anatomical and functional asymmetries in primates. We next consider and present data on the hypothesis that hemispheric specialization evolved as a by-product of increasing brain size relative to the surface area of the corpus callosum in different primate species. Last, we discuss some of the challenges in the study of hemispheric specialization in primates and offer some suggestions on how to advance the field. © 2015 New York Academy of Sciences.

Interaction of a parabolic-shaped pulse pair in a passively mode-locked Yb-doped fiber laser

NASA Astrophysics Data System (ADS)

Wang, Da-Shuai; Wu, Ge; Gao, Bo; Tian, Xiao-Jian

2013-01-01

We numerically investigate the formation and interaction of a parabolic-shaped pulse pair in a passively mode-locked Yb-doped fiber laser. Based on a lumped model, the parabolic-shaped pulse pair is obtained by controlling the inter-cavity average dispersion and gain saturation energy, Moreover, pulse repulsive and attractive motion are also achieved with different pulse separations. Simulation results show that the phase shift plays an important role in pulse interaction, and the interaction is determined by the inter-cavity average dispersion and gain saturation energy, i.e., the strength of the interaction is proportional to the gain saturation energy, a stronger gain saturation energy will result in a higher interaction intensity. On the contrary, the increase of the inter-cavity dispersion will counterbalance some interaction force. The results also show that the interaction of a parabolic-shaped pulse pair has a larger interaction distance compared to conventional solitons.

Policy statement—Climatic heat stress and exercising children and adolescents.

PubMed

Bergeron, Michael F; Devore, Cynthia; Rice, Stephen G

2011-09-01

Results of new research indicate that, contrary to previous thinking, youth do not have less effective thermoregulatory ability, insufficient cardiovascular capacity, or lower physical exertion tolerance compared with adults during exercise in the heat when adequate hydration is maintained. Accordingly, besides poor hydration status, the primary determinants of reduced performance and exertional heat-illness risk in youth during sports and other physical activities in a hot environment include undue physical exertion, insufficient recovery between repeated exercise bouts or closely scheduled same-day training sessions or rounds of sports competition, and inappropriately wearing clothing, uniforms, and protective equipment that play a role in excessive heat retention. Because these known contributing risk factors are modifiable, exertional heat illness is usually preventable. With appropriate preparation, modifications, and monitoring, most healthy children and adolescents can safely participate in outdoor sports and other physical activities through a wide range of challenging warm to hot climatic conditions.

Cooperative functions of duetting behaviour in tropical wrens

NASA Astrophysics Data System (ADS)

Kovach, Kristin Ashley

Vocal duets occur when two breeding partners coordinate their songs into a joint display. Duetting serves functions both within and between pairs, and functionality is often context dependent. I explore the function of temporal coordination of male and female songs into duets, testing the hypothesis that coordinated duets are more threatening territorial signals than poorly coordinated duets or solos in three closely related species of wren. Results indicate that birds respond with similar levels of physical aggression to all three levels of coordination; however, they sing more duets in response to both categories of duets. I also explore duets and other vocalizations as they are used during breeding, testing the hypothesis that duets play a role in coordinating nest visitation. Contrary to my predictions, the birds sang the most duets during the incubation stage. My results suggest that duets are used for both territory defence and communication at the nest.

Candida-associated gastric ulcer relapsing in a different position with a different appearance.

PubMed

Sasaki, Kenji

2012-08-28

An 87-year-old, Japanese woman was shown to have a submucosal tumor-like lesion with a deep, central ulceration covered with thick, whitish exudate in the stomach. Biopsy showed Candida tropicalis but not Helicobacter pylori (H. pylori). She had no predisposing factors or history of peptic ulcers nor had taken non-steroidal anti-inflammatory drugs (NSAIDs), diagnosed with Candida-associated gastric ulcer. Though cured of the lesion, she developed another ulcer in a different position, in which Candida was demonstrated but H. pylori was undetectable. This is the first case of recurrent Candida-associated gastric ulcer in the world. Detected in both the original and recurrent lesions in an H. pylori-negative patient with no antecedent ulcers who had not taken NSAIDs, Candida is considered, contrary to the prevailing opinion, to play an etiologic role in ulcer formation.

Discovery of a photoresponse amplification mechanism in compensated PN junctions

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

Zhou, Yuchun; Rahman, Samia N.; Hall, David

2015-01-19

We report the experimental evidence of uncovering a photoresponse amplification mechanism in heavily doped, partially compensated silicon p-n junctions under very low bias voltage. We show that the observed photocurrent gain occurs at a bias that is more than an order of magnitude below the threshold voltage for conventional impact ionization. Moreover, contrary to the case of avalanche detectors and p-i-n diodes, the amplified photoresponse is enhanced rather than suppressed with increasing temperature. These distinctive characteristics lead us to hypothesize that the inelastic scattering between energetic electrons (holes) and the ionized impurities in the depletion and charge neutral regions ofmore » the p-n junction in a cyclic manner plays a significant role in the amplification process. Such an internal signal amplification mechanism, which occurs at much lower bias than impact ionization and favors room temperature over cryogenic temperature, makes it promising for practical device applications.« less

Emplotting Hikikomori: Japanese Parents' Narratives of Social Withdrawal.

PubMed

Rubinstein, Ellen

2016-12-01

Hikikomori, often glossed as "social withdrawal," emerged as a sociomedical condition among Japanese youth at the end of the twentieth century, and it continues to fascinate and concern the public. Explanatory frameworks for hikikomori abound, with different stakeholders attributing it to individual psychopathology, poor parenting, and/or a lack of social support structures. This article takes an interpretive approach to hikikomori by exploring parents' narrative constructions of hikikomori children in support group meetings and in-depth interviews. I argue that some parents were able to find hope in hikikomori by 'emplotting' their children's experiences into a larger narrative about onset, withdrawal, and recovery, which helped them remain invested in the present by maintaining a sense of possibility about the future. Contrary to literature that examines hikikomori as an epidemic of isolated individuals, I demonstrate how parents play a key role in hikikomori through meaning-making activities that have the potential to shape their children's experiences of withdrawal.

Gender differences in personality traits across cultures: robust and surprising findings.

PubMed

Costa, Paul T; Terracciano, Antonio; McCrae, Robert R

2001-08-01

Secondary analyses of Revised NEO Personality Inventory data from 26 cultures (N = 23,031) suggest that gender differences are small relative to individual variation within genders; differences are replicated across cultures for both college-age and adult samples, and differences are broadly consistent with gender stereotypes: Women reported themselves to be higher in Neuroticism, Agreeableness, Warmth, and Openness to Feelings, whereas men were higher in Assertiveness and Openness to Ideas. Contrary to predictions from evolutionary theory, the magnitude of gender differences varied across cultures. Contrary to predictions from the social role model, gender differences were most pronounced in European and American cultures in which traditional sex roles are minimized. Possible explanations for this surprising finding are discussed, including the attribution of masculine and feminine behaviors to roles rather than traits in traditional cultures.

Redefinition of rubisco carboxylase reaction reveals origin of water for hydration and new roles for active-site residues.

PubMed

Kannappan, Babu; Gready, Jill E

2008-11-12

Crystallographic, mutagenesis, kinetic, and computational studies on Rubisco over three decades have revealed much about its catalytic mechanism and the role played by several active-site residues. However, key questions remain unanswered. Specific details of the carboxylase and oxygenase mechanisms, required to underpin the rational re-engineering of Rubisco, are still speculative. Here we address critical gaps in knowledge with a definitive comprehensive computational investigation of the mechanism of carboxylase activity at the Rubisco active site. Density functional theory calculations (B3LYP/6-31G(d,p)) were performed on active-site fragment models of a size up to 77 atoms, not previously possible computationally. All amino acid residues suspected to play roles in the acid-base chemistry in the multistep reaction, and interacting directly with the central Mg (2+) atom and the reactive moiety of substrate and intermediates, were included. The results provide a firm basis for us to propose a novel mechanism for the entire sequence of reactions in the carboxylase catalysis and to define precise roles for the active-site residues, singly and in concert. In this mechanism, the carbamylated LYS201 plays a more limited role than previously proposed but is crucial for initiating the reaction by acting as a base in the enolization. We suggest a wider role for HIS294, with involvement in the carboxylation, hydration, and C2-C3 bond-scission steps, consistent with the suggestion of Harpel et al. (1998) but contrary to the consensus view of Cleland et al. (1998). In contrast to the common assumption that the water molecule for the hydration step comes from within the active site, we propose that the Mg-coordinated water is not dissociated at the start of the gas-addition reaction but rather remains coordinated and is used for the hydration of the C3 carbon atom. New roles are also proposed for LYS175, GLU204, and HIS294. The mechanism suggests roles in the gas-addition step for residues in three spatially distinct regions of the active site, HIS294 and LYS334 in the C-terminal domain of the large subunit (LSU), but also hitherto unsuspected roles for a cluster of three residues (ASN123, GLU60, and TYR20) in the N-terminal domain of the partner LSU of the dimer containing the active site. Our new mechanism is supported by existing experimental data, provides new convincing interpretations of previously puzzling data, and allows new insights into mutational strategies for improving Rubisco activity.

Explanatory Emotion Talk in Mexican Immigrant and Mexican American Families.

ERIC Educational Resources Information Center

Cervantes, Christi A.

2002-01-01

Mother-child conversations during story-telling play were analyzed for patterns of emotion talk. Subjects were 48 Mexican immigrant and Mexican American mothers and their children aged 3-4. Contrary to previous findings, Mexican immigrant mothers used more explanations of emotions than labels. Mexican American mothers used both, equally. Results…

Pretending to Play or Playing to Pretend: The Case of Autism.

PubMed

Kasari, Connie; Chang, Ya-Chih; Patterson, Stephanie

2013-01-01

An article by Angeline S. Lillard and others published in the January 2013 issue of Psychological Bulletin about the impact of pretend play on child development raised a number of issues about play studies and child psychology. They claimed that, contrary to current theories on the subject, the evidence of many studies does not support causal explanations of play's relationship to most childhood development. In this article, authors Kasari, Chang, and Patterson review these arguments about play and devlopment in relation to children with autism-children who show specific deficits in pretend play. They argue that the study of these children provides a unique opportunity to consider which elements in play are important and how play skills are associated with different periods of child development. They conclude that, because pretend play requires intervention for the majority of children with autism, improving pretense in these children may shed more light on the causal impact of pretense on later developing skills in children. Key words: child development and pretend play; children with autism; funtional play; intervention in play; symbol play.

The PAS domains of the major sporulation kinase in Bacillus subtilis play a role in tetramer formation that is essential for the autokinase activity.

PubMed

Kiehler, Brittany; Haggett, Lindsey; Fujita, Masaya

2017-08-01

Sporulation in Bacillus subtilis is induced upon starvation. In a widely accepted model, an N-terminal "sensor" domain of the major sporulation kinase KinA recognizes a hypothetical starvation signal(s) and autophosphorylates a histidine residue to activate the master regulator Spo0A via a multicomponent phosphorelay. However, to date no confirmed signal has been found. Here, we demonstrated that PAS-A, the most N-terminal of the three PAS domains (PAS-ABC), is dispensable for the activity, contrary to a previous report. Our data indicated that the autokinase activity is dependent on the formation of a functional tetramer, which is mediated by, at least, PAS-B and PAS-C. Additionally, we ruled out the previously proposed notion that NAD + /NADH ratio controls KinA activity through the PAS-A domain by demonstrating that the cofactors show no effects on the kinase activity in vitro. In support of these data, we found that the cofactors exist in approximately 1000-fold excess of KinA in the cell and the cofactors' ratio does not change significantly during growth and sporulation, suggesting that changes in the cofactor ratio might not play a role in controlling KinA activity. These data may refute the widely-held belief that the activity of KinA is regulated in response to an unknown starvation signal(s). © 2017 The Authors. MicrobiologyOpen published by John Wiley & Sons Ltd.

Neuronal connectivity and interactions between the auditory and limbic systems. Effects of noise and tinnitus.

PubMed

Kraus, Kari Suzanne; Canlon, Barbara

2012-06-01

Acoustic experience such as sound, noise, or absence of sound induces structural or functional changes in the central auditory system but can also affect limbic regions such as the amygdala and hippocampus. The amygdala is particularly sensitive to sound with valence or meaning, such as vocalizations, crying or music. The amygdala plays a central role in auditory fear conditioning, regulation of the acoustic startle response and can modulate auditory cortex plasticity. A stressful acoustic stimulus, such as noise, causes amygdala-mediated release of stress hormones via the HPA-axis, which may have negative effects on health, as well as on the central nervous system. On the contrary, short-term exposure to stress hormones elicits positive effects such as hearing protection. The hippocampus can affect auditory processing by adding a temporal dimension, as well as being able to mediate novelty detection via theta wave phase-locking. Noise exposure affects hippocampal neurogenesis and LTP in a manner that affects structural plasticity, learning and memory. Tinnitus, typically induced by hearing malfunctions, is associated with emotional stress, depression and anatomical changes of the hippocampus. In turn, the limbic system may play a role in the generation as well as the suppression of tinnitus indicating that the limbic system may be essential for tinnitus treatment. A further understanding of auditory-limbic interactions will contribute to future treatment strategies of tinnitus and noise trauma. Copyright © 2012 Elsevier B.V. All rights reserved.

Trends in Education-Specific Life Expectancy, Data Quality, and Shifting Education Distributions: A Note on Recent Research.

PubMed

Hendi, Arun S

2017-06-01

Several recent articles have reported conflicting conclusions about educational differences in life expectancy, and this is partly due to the use of unreliable data subject to a numerator-denominator bias previously reported as ranging from 20 % to 40 %. This article presents estimates of life expectancy and lifespan variation by education in the United States using more reliable data from the National Health Interview Survey. Contrary to prior conclusions in the literature, I find that life expectancy increased or stagnated since 1990 among all education-race-sex groups except for non-Hispanic white women with less than a high school education; there has been a robust increase in life expectancy among white high school graduates and a smaller increase among black female high school graduates; lifespan variation did not increase appreciably among high school graduates; and lifespan variation plays a very limited role in explaining educational gradients in mortality. I also discuss the key role that educational expansion may play in driving future changes in mortality gradients. Because of shifting education distributions, within an education-specific synthetic cohort, older age groups are less negatively selected than younger age groups. We could thus expect a greater concentration of mortality at younger ages among people with a high school education or less, which would be reflected in increasing lifespan variability for this group. Future studies of educational gradients in mortality should use more reliable data and should be mindful of the effects of shifting education distributions.

Impacts of Topographic Shading on Surface Energy Balance of High Mountain Asia Glaciers

NASA Astrophysics Data System (ADS)

Olson, M.; Rupper, S.

2016-12-01

Topographic shading plays an important role in the energy balance of valley glaciers. While previous studies incorporate shading of varying complexity in surface energy balance models, to date, no large-scale studies have explored in depth the effects of topographic shading on glacier surface energy balance, and how these vary geographically within High Mountain Asia (HMA). Here we develop a model to examine the variability in potential insolation during the summer melt season using the ASTER GDEM and multi-hour solar geometry to simulate topographic shading on an idealized glacier. Shading is calculated in simulations utilizing a range of slopes, aspects, and latitudes. We test glacier mass balance sensitivity to these parameters for a suite of glaciers throughout HMA. Our results show that shading impacts on glaciers in HMA are highly variable across different geographic regions, but that they are largely predictable based on topographic characteristics such as slope and aspect. For example, we find in regions with steep topography and high relief that shading frequently dominates in the ablation zone rather than the accumulation zone, contrary to the findings of some previous studies. In these regions, topographic shading may play a more significant role in glacier energy balance. These results will better define the effects of topographic shading on surface energy balance, and improve model accuracy within HMA. Additionally, this topographic shading model provides a framework to quantify how shading effects vary for advancing or retreating glaciers as they respond to fluctuations in climate across HMA.

MAPK Target Sites of Eyes Absent Are Not Required for Eye Development or Survival in Drosophila

PubMed Central

Jusiak, Barbara; Abulimiti, Abuduaini; Haelterman, Nele; Chen, Rui; Mardon, Graeme

2012-01-01

Eyes absent (Eya) is a highly conserved transcription cofactor and protein phosphatase that plays an essential role in eye development and survival in Drosophila. Ectopic eye induction assays using cDNA transgenes have suggested that mitogen activated protein kinase (MAPK) activates Eya by phosphorylating it on two consensus target sites, S402 and S407, and that this activation potentiates the ability of Eya to drive eye formation. However, this mechanism has never been tested in normal eye development. In the current study, we generated a series of genomic rescue transgenes to investigate how loss- and gain-of-function mutations at these two MAPK target sites within Eya affect Drosophila survival and normal eye formation: eya+GR, the wild-type control; eyaSAGR, which lacks phosphorylation at the two target residues; and eyaSDEGR, which contains phosphomimetic amino acids at the same two residues. Contrary to the previous studies in ectopic eye development, all eya genomic transgenes tested rescue both eye formation and survival equally effectively. We conclude that, in contrast to ectopic eye formation, MAPK-mediated phosphorylation of Eya on S402 and S407 does not play a role in normal development. This is the first study in Drosophila to evaluate the difference in outcomes between genomic rescue and ectopic cDNA-based overexpression of the same gene. These findings indicate similar genomic rescue strategies may prove useful for re-evaluating other long-standing Drosophila developmental models. PMID:23251383

Analysis of the causes of spawning of large-scale, severe malarial epidemics and their rapid total extinction in western Provence, historically a highly endemic region of France (1745–1850)

PubMed Central

2014-01-01

Background The two main puzzles of this study are the onset and then sudden stopping of severe epidemics in western Provence (a highly malaria-endemic region of Mediterranean France) without any deliberate counter-measures and in the absence of significant population flux. Methods Malaria epidemics during the period from 1745 to 1850 were analysed against temperature and rainfall records and several other potentially relevant factors. Results Statistical analyses indicated that relatively high temperatures in early spring and in September/October, rainfall during the previous winter (principally December) and even from November to September and epidemics during the previous year could have played a decisive role in the emergence of these epidemics. Moreover, the epidemics were most likely not driven by other parameters (e.g., social, cultural, agricultural and geographical). Until 1776, very severe malarial epidemics affected large areas, whereas after this date, they were rarer and generally milder for local people and were due to canal digging activities. In the latter period, decreased rainfall in December, and more extreme and variable temperatures were observed. It is known that rainfall anomalies and temperature fluctuations may be detrimental to vector and parasite development. Conclusion This study showed the particular characteristics of malaria in historical Provence. Contrary to the situation in most other Mediterranean areas, Plasmodium falciparum was most likely not involved (during the years with epidemics, the mean temperature during the months of July and August, among other factors, did not play a role) and the population had no protective mutation. The main parasite species was Plasmodium vivax, which was responsible for very severe diseases, but contrary to in northern Europe, it is likely that transmission occurred only during the period where outdoor sporogony was possible, and P. vivax sporogony was always feasible, even during colder summers. Possible key elements in the understanding of the course of malaria epidemics include changes in the virulence of P. vivax strains, the refractoriness of anophelines and/or the degree or efficiency of acquired immunity. This study could open new lines of investigation into the comprehension of the conditions of disappearance/emergence of severe malaria epidemics in highly endemic areas. PMID:24581282

Insurance World in Transition: Changes in Global Risk Taking and Risk Assessment

NASA Astrophysics Data System (ADS)

Michel, Gero; Tiampo, Kristy

2015-04-01

Catastrophe insurance risk assessment, risk taking, and regulation has evolved over the last 20 years and is gearing up for significant further change in the years ahead. Changes in regulation and influx of capital have put profit margins for catastrophe risk products under pressure despite the fact that changes in climate as well as increasing insurance penetration is expected to heighten demand. As a result, reinsurance strategies are moving away from catastrophe risk. In addition, lower margins require cheaper and more efficient risk assessment methods and processes which are contrary to evolving analytical tools and methods that had increased expenses in line with growing margins over the last decade. New capital providers are less familiar with and less willing to accept complex supply chains for risk management, relationship-driven business and tedious data exchange and management processes. Risk takers claim new measures and ask for more flexibility in the use of tools. The current concepts of catastrophe insurance risk assessment are hence under thorough scrutiny. This presentation deals with the changing landscape in catastrophe insurance risk assessment and risk hedging and discusses changes in catastrophe risk assessment products and demand. How likely is it that private, small and nimble hazard and risk consulting groups - increasingly emanating from larger science organizations - will replace large established firms in their role to assess risk? What role do public-private academic partnerships play in assuming risk for catastrophe insurance and what role could they play in the future? What are the opportunities and downsides of the current changes in risk taking and hedging? What is needed from the scientific community in order to fill the gaps in risk management and who is likely to take advantage of the current changes?

Probing the Role of Nascent Helicity in p27 Function as a Cell Cycle Regulator

PubMed Central

Otieno, Steve; Kriwacki, Richard

2012-01-01

p27 regulates the activity of Cdk complexes which are the principal governors of phase transitions during cell division. Members of the p27 family of proteins, which also includes p21 and p57, are called the Cip/Kip cyclin-dependent kinase regulators (CKRs). Interestingly, the Cip/Kip CKRs play critical roles in cell cycle regulation by being intrinsically unstructured, a characteristic contrary to the classical structure-function paradigm. They exhibit nascent helicity which has been localized to a segment referred to as sub-domain LH. The nascent helicity of this sub-domain is conserved and we hypothesize that it is an important determinant of their functional properties. To test this hypothesis, we successfully designed and prepared p27 variants in which domain LH was either more or less helical with respect to the wild-type protein. Thermal denaturation experiments showed that the ternary complexes of the p27 variants bound to Cdk2/Cyclin A were less stable compared to the wild-type complex. Isothermal titration calorimetry experiments showed a decrease in the enthalpy of binding for all the mutants with respect to p27. The free energies of binding varied within a much narrower range. In vitro Cdk2 inhibition assays showed that the p27 variants exhibited disparate inhibitory potencies. Furthermore, when over-expressed in NIH 3T3 mouse fibroblast cells, the less helical p27 variants were less effective in causing cell cycle arrest relative to the wild-type p27. Our results indicate that the nascent helicity of sub-domain LH plays a key role mediating the biological function of p27. PMID:23071750

Biomineralization changes with food supply confer juvenile scallops (Argopecten purpuratus) resistance to ocean acidification.

PubMed

Ramajo, Laura; Marbà, Núria; Prado, Luis; Peron, Sophie; Lardies, Marco A; Rodriguez-Navarro, Alejandro B; Vargas, Cristian A; Lagos, Nelson A; Duarte, Carlos M

2016-06-01

Future ocean acidification (OA) will affect physiological traits of marine species, with calcifying species being particularly vulnerable. As OA entails high energy demands, particularly during the rapid juvenile growth phase, food supply may play a key role in the response of marine organisms to OA. We experimentally evaluated the role of food supply in modulating physiological responses and biomineralization processes in juveniles of the Chilean scallop, Argopecten purpuratus, that were exposed to control (pH ~ 8.0) and low pH (pH ~ 7.6) conditions using three food supply treatments (high, intermediate, and low). We found that pH and food levels had additive effects on the physiological response of the juvenile scallops. Metabolic rates, shell growth, net calcification, and ingestion rates increased significantly at low pH conditions, independent of food. These physiological responses increased significantly in organisms exposed to intermediate and high levels of food supply. Hence, food supply seems to play a major role modulating organismal response by providing the energetic means to bolster the physiological response of OA stress. On the contrary, the relative expression of chitin synthase, a functional molecule for biomineralization, increased significantly in scallops exposed to low food supply and low pH, which resulted in a thicker periostracum enriched with chitin polysaccharides. Under reduced food and low pH conditions, the adaptive organismal response was to trade-off growth for the expression of biomineralization molecules and altering of the organic composition of shell periostracum, suggesting that the future performance of these calcifiers will depend on the trajectories of both OA and food supply. Thus, incorporating a suite of traits and multiple stressors in future studies of the adaptive organismal response may provide key insights on OA impacts on marine calcifiers. © 2015 John Wiley & Sons Ltd.

Sortilin regulates progranulin action in castration-resistant prostate cancer cells.

PubMed

Tanimoto, Ryuta; Morcavallo, Alaide; Terracciano, Mario; Xu, Shi-Qiong; Stefanello, Manuela; Buraschi, Simone; Lu, Kuojung G; Bagley, Demetrius H; Gomella, Leonard G; Scotlandi, Katia; Belfiore, Antonino; Iozzo, Renato V; Morrione, Andrea

2015-01-01

The growth factor progranulin is as an important regulator of transformation in several cellular systems. We have previously demonstrated that progranulin acts as an autocrine growth factor and stimulates motility, proliferation, and anchorage-independent growth of castration-resistant prostate cancer cells, supporting the hypothesis that progranulin may play a critical role in prostate cancer progression. However, the mechanisms regulating progranulin action in castration-resistant prostate cancer cells have not been characterized. Sortilin, a single-pass type I transmembrane protein of the vacuolar protein sorting 10 family, binds progranulin in neurons and negatively regulates progranulin signaling by mediating progranulin targeting for lysosomal degradation. However, whether sortilin is expressed in prostate cancer cells and plays any role in regulating progranulin action has not been established. Here, we show that sortilin is expressed at very low levels in castration-resistant PC3 and DU145 cells. Significantly, enhancing sortilin expression in PC3 and DU145 cells severely diminishes progranulin levels and inhibits motility, invasion, proliferation, and anchorage-independent growth. In addition, sortilin overexpression negatively modulates Akt (protein kinase B, PKB) stability. These results are recapitulated by depleting endogenous progranulin in PC3 and DU145 cells. On the contrary, targeting sortilin by short hairpin RNA approaches enhances progranulin levels and promotes motility, invasion, and anchorage-independent growth. We dissected the mechanisms of sortilin action and demonstrated that sortilin promotes progranulin endocytosis through a clathrin-dependent pathway, sorting into early endosomes and subsequent lysosomal degradation. Collectively, these results point out a critical role for sortilin in regulating progranulin action in castration-resistant prostate cancer cells, suggesting that sortilin loss may contribute to prostate cancer progression.

Sortilin Regulates Progranulin Action in Castration-Resistant Prostate Cancer Cells

PubMed Central

Tanimoto, Ryuta; Morcavallo, Alaide; Terracciano, Mario; Xu, Shi-Qiong; Stefanello, Manuela; Buraschi, Simone; Lu, Kuojung G.; Bagley, Demetrius H.; Gomella, Leonard G.; Scotlandi, Katia; Belfiore, Antonino; Iozzo, Renato V.

2015-01-01

The growth factor progranulin is as an important regulator of transformation in several cellular systems. We have previously demonstrated that progranulin acts as an autocrine growth factor and stimulates motility, proliferation, and anchorage-independent growth of castration-resistant prostate cancer cells, supporting the hypothesis that progranulin may play a critical role in prostate cancer progression. However, the mechanisms regulating progranulin action in castration-resistant prostate cancer cells have not been characterized. Sortilin, a single-pass type I transmembrane protein of the vacuolar protein sorting 10 family, binds progranulin in neurons and negatively regulates progranulin signaling by mediating progranulin targeting for lysosomal degradation. However, whether sortilin is expressed in prostate cancer cells and plays any role in regulating progranulin action has not been established. Here, we show that sortilin is expressed at very low levels in castration-resistant PC3 and DU145 cells. Significantly, enhancing sortilin expression in PC3 and DU145 cells severely diminishes progranulin levels and inhibits motility, invasion, proliferation, and anchorage-independent growth. In addition, sortilin overexpression negatively modulates Akt (protein kinase B, PKB) stability. These results are recapitulated by depleting endogenous progranulin in PC3 and DU145 cells. On the contrary, targeting sortilin by short hairpin RNA approaches enhances progranulin levels and promotes motility, invasion, and anchorage-independent growth. We dissected the mechanisms of sortilin action and demonstrated that sortilin promotes progranulin endocytosis through a clathrin-dependent pathway, sorting into early endosomes and subsequent lysosomal degradation. Collectively, these results point out a critical role for sortilin in regulating progranulin action in castration-resistant prostate cancer cells, suggesting that sortilin loss may contribute to prostate cancer progression. PMID:25365768

Educational privilege: The role of school context in the development just world beliefs among Brazilian adolescents.

PubMed

Thomas, Kendra J; Napolitano, Patricia H

2017-12-01

The purpose of this study is to understand the development of Brazilian adolescents' justice perceptions across different contexts of educational privilege. Past research has found that, in adolescence, the belief in a just world (BJW) differentiates between personal and general and declines. However, prior research has not included adolescents from various socioeconomic statuses, samples in Latin America, or focused on the role of the educational context on the developmental trajectory. Participants were 385 adolescents from 3 schools (private, public and military) in Southern Brazil between 9th and 11th grade. Students completed the personal and general BJW survey. Results revealed a significant interaction of school and grade level of adolescents' personal BJW. Contrary to previous research, personal and general BJW was not always lower in higher grades. Among privileged educational contexts, data indicated that personal BJW may even increase, with the decrease notable in the lower resourced school. In contrast, general BJW was relatively consistent across all Brazilian adolescents. Results provide important insight into the role that privilege and education play across adolescents' development of BJW. This research questions the generalizability of previous studies on the development of BJW and indicates that the trajectory may be dependent upon educational and cultural context. © 2016 International Union of Psychological Science.

Motor facilitation during observation of implied motion: Evidence for a role of the left dorsolateral prefrontal cortex.

PubMed

Mineo, Ludovico; Fetterman, Alexander; Concerto, Carmen; Warren, Michael; Infortuna, Carmenrita; Freedberg, David; Chusid, Eileen; Aguglia, Eugenio; Battaglia, Fortunato

2018-06-01

The phenomenon of motor resonance (the increase in motor cortex excitability during observation of actions) has been previously described. Transcranial magnetic stimulation (TMS) studies have demonstrated a similar effect during perception of implied motion (IM). The left dorsolateral prefrontal cortex (DLPFC) seems to be activated during action observation. Furthermore, the role of this brain area in motor resonance to IM is yet to be investigated. Fourteen healthy volunteers were enrolled into the study. We used transcranial direct current stimulation (tDCS) to stimulate DLPFC aiming to investigate whether stimulation with different polarities would affect the amplitude of motor evoked potential collected during observation of images with and without IM. The results of our experiment indicated that Cathodal tDCS over the left DLPFC prevented motor resonance during observation of IM. On the contrary, anodal and sham tDCS did not significantly modulate motor resonance to IM. The current study expands the understanding of the neural circuits engaged during observation of IM. Our results are consistent with the hypothesis that action understanding requires the interaction of large networks and that the left DLPFC plays a crucial role in generating motor resonance to IM. Copyright © 2018 Elsevier B.V. All rights reserved.

Auditory orienting of attention: Effects of cues and verbal workload with children and adults.

PubMed

Phélip, Marion; Donnot, Julien; Vauclair, Jacques

2016-01-01

The use of tone cues has an improving effect on the auditory orienting of attention for children as for adults. Verbal cues, on the contrary, do not seem to orient attention as efficiently before the age of 9 years. However, several studies have reported inconsistent effects of orienting attention on ear asymmetries. Multiple factors are questioned, such as the role of verbal workload. Indeed, the semantic nature of the dichotic pairs and their load of processing may explain orienting of attention performance. Thus, by controlling for the role of verbal workload, the present experiment aimed to evaluate the development of capacities for the auditory orienting of attention. Right-handed, 6- to 12-year-olds and adults were recruited to complete either a tone cue or a verbal cue dichotic listening task in the identification of familiar words or nonsense words. A factorial design analysis of variance showed a significant right-ear advantage for all the participants and for all the types of stimuli. A major developmental effect was observed in which verbal cues played an important role: they allowed the 6- to 8-year-olds to improve their performance of identification in the left ear. These effects were taken as evidence of the implication of top-down processes in cognitive flexibility across development.

Virulence factor rtx in Legionella pneumophila, evidence suggesting it is a modular multifunctional protein.

PubMed

D'Auria, Giuseppe; Jiménez, Núria; Peris-Bondia, Francesc; Pelaz, Carmen; Latorre, Amparo; Moya, Andrés

2008-01-14

The repeats in toxin (Rtx) are an important pathogenicity factor involved in host cells invasion of Legionella pneumophila and other pathogenic bacteria. Its role in escaping the host immune system and cytotoxic activity is well known. Its repeated motives and modularity make Rtx a multifunctional factor in pathogenicity. The comparative analysis of rtx gene among 6 strains of L. pneumophila showed modularity in their structures. Among compared genomes, the N-terminal region of the protein presents highly dissimilar repeats with functionally similar domains. On the contrary, the C-terminal region is maintained with a fashionable modular configuration, which gives support to its proposed role in adhesion and pore formation. Despite the variability of rtx among the considered strains, the flanking genes are maintained in synteny and similarity. In contrast to the extracellular bacteria Vibrio cholerae, in which the rtx gene is highly conserved and flanking genes have lost synteny and similarity, the gene region coding for the Rtx toxin in the intracellular pathogen L. pneumophila shows a rapid evolution. Changes in the rtx could play a role in pathogenicity. The interplay of the Rtx toxin with host membranes might lead to the evolution of new variants that are able to escape host cell defences.

Sex Roles, Feminism, and Achievement Conflicts.

ERIC Educational Resources Information Center

Miller, Frederick D.; And Others

The relationships between masculinity and femininity as measured by the Bem Sex Role Inventory (BSRI), achievement conflicts (fear of success and fear of failure), and a variety of attitudes in men and women were examined in three survey studies. Contrary to Bem's suggestion that femininity in women serves to dampen independent and assertive…

Single molecule transcription factor dynamics in the syncytial Drosophila embryo

NASA Astrophysics Data System (ADS)

Darzacq, Xavier

During early development in the Drosophila embryo, cell fates are determined over the course of just 2 hours with exquisite spatio-temoral precision. One of the key regulators of this process is the transcription factor Bicoid which forms a concentration gradient across the long axis of the embryo. Although Bicoids' primary role is activation at the anterior, where concentrations are highest, it is also known to play a role in the posterior where there are only 100s of molecules per nucleus. Understanding how Bicoid can find its target at such low concentrations has remained intractable, largely due to the inability to perform single molecule imaging in the context of the developing embryo. Here we use lattice light sheet microscopy to overcome the technical barriers of sample thickness and auto-fluorescence to characterize the single molecule dynamics of Bicoid. We find that off-rates do not vary across the embryo and that instead the on-rates are modulated through the formation of clusters that enrich local concentration. This data is contrary to the current concentration dependent model of Bicoid function since local concentration within the nucleus is now a regulated parameter and suggests a previously unknown mechanism for regulation at extremely low concentrations.

Disruption of TTDA Results in Complete Nucleotide Excision Repair Deficiency and Embryonic Lethality

PubMed Central

Theil, Arjan F.; Nonnekens, Julie; Steurer, Barbara; Mari, Pierre-Olivier; de Wit, Jan; Lemaitre, Charlène; Marteijn, Jurgen A.; Raams, Anja; Maas, Alex; Vermeij, Marcel; Essers, Jeroen; Hoeijmakers, Jan H. J.; Giglia-Mari, Giuseppina; Vermeulen, Wim

2013-01-01

The ten-subunit transcription factor IIH (TFIIH) plays a crucial role in transcription and nucleotide excision repair (NER). Inactivating mutations in the smallest 8-kDa TFB5/TTDA subunit cause the neurodevelopmental progeroid repair syndrome trichothiodystrophy A (TTD-A). Previous studies have shown that TTDA is the only TFIIH subunit that appears not to be essential for NER, transcription, or viability. We studied the consequences of TTDA inactivation by generating a Ttda knock-out (Ttda−/−) mouse-model resembling TTD-A patients. Unexpectedly, Ttda−/− mice were embryonic lethal. However, in contrast to full disruption of all other TFIIH subunits, viability of Ttda−/− cells was not affected. Surprisingly, Ttda−/− cells were completely NER deficient, contrary to the incomplete NER deficiency of TTD-A patient-derived cells. We further showed that TTD-A patient mutations only partially inactivate TTDA function, explaining the relatively mild repair phenotype of TTD-A cells. Moreover, Ttda−/− cells were also highly sensitive to oxidizing agents. These findings reveal an essential role of TTDA for life, nucleotide excision repair, and oxidative DNA damage repair and identify Ttda−/− cells as a unique class of TFIIH mutants. PMID:23637614

The role of individual differences in the accuracy of confidence judgments.

PubMed

Pallier, Gerry; Wilkinson, Rebecca; Danthiir, Vanessa; Kleitman, Sabina; Knezevic, Goran; Stankov, Lazar; Roberts, Richard D

2002-07-01

Generally, self-assessment of accuracy in the cognitive domain produces overconfidence, whereas self-assessment of visual perceptual judgments results in underconfidence. Despite contrary empirical evidence, in models attempting to explain those phenomena, individual differences have often been disregarded. The authors report on 2 studies in which that shortcoming was addressed. In Experiment 1, participants (N= 520) completed a large number of cognitive-ability tests. Results indicated that individual differences provide a meaningful source of overconfidence and that a metacognitive trait might mediate that effect. In further analysis, there was only a relatively small correlation between test accuracy and confidence bias. In Experiment 2 (N = 107 participants), both perceptual and cognitive ability tests were included, along with measures of personality. Results again indicated the presence of a confidence factor that transcended the nature of the testing vehicle. Furthermore, a small relationship was found between that factor and some self-reported personality measures. Thus, personality traits and cognitive ability appeared to play only a small role in determining the accuracy of self-assessment. Collectively, the present results suggest that there are multiple causes of miscalibration, which current models of over- and underconfidence fail to encompass.

The role of smart systems in rendezvous, close proximity operations and docking maneuvers

NASA Astrophysics Data System (ADS)

Szatkowski, Gerard P.

Various missions scenarios (Space Station logistics, LEO and GEO services, and SEI operation) will involve flexibility in mission management. This means operations will be one or a combination of the following: autonomous, supervised autonomous, and machine aided manual control. Smart Systems will likely play a significant role in making these missions successful from a safety/reliability perspective and less costly from an operations perspective. This does not imply that Smart Systems need to be super sophisticated. On the contrary, Smart Systems have been described as automated intelligence that if a person had done it wrong, it would be considered stupid. The first part of this paper will describe the types of Smart System techniques involved in AR and CC, their specifications, duties, and interactions. Next will be a discussion of the work performed under the auspice of the ALS Program to further Expert Systems applications imbedded in the control process, NASA/JSC CRAD, and other related IRAD projects. This will include issues pertaining to the following: integration, speed, knowledge encapsulation, and cooperative systems. Finally, a brief description will be offered to outline the major obstacles for the acceptance of Smart Systems in critical applications.

The Pax gene family: Highlights from cephalopods

PubMed Central

Baratte, Sébastien; Andouche, Aude; Bonnaud-Ponticelli, Laure

2017-01-01

Pax genes play important roles in Metazoan development. Their evolution has been extensively studied but Lophotrochozoa are usually omitted. We addressed the question of Pax paralog diversity in Lophotrochozoa by a thorough review of available databases. The existence of six Pax families (Pax1/9, Pax2/5/8, Pax3/7, Pax4/6, Paxβ, PoxNeuro) was confirmed and the lophotrochozoan Paxβ subfamily was further characterized. Contrary to the pattern reported in chordates, the Pax2/5/8 family is devoid of homeodomain in Lophotrochozoa. Expression patterns of the three main pax classes (pax2/5/8, pax3/7, pax4/6) during Sepia officinalis development showed that Pax roles taken as ancestral and common in metazoans are modified in S. officinalis, most likely due to either the morphological specificities of cephalopods or to their direct development. Some expected expression patterns were missing (e.g. pax6 in the developing retina), and some expressions in unexpected tissues have been found (e.g. pax2/5/8 in dermal tissue and in gills). This study underlines the diversity and functional plasticity of Pax genes and illustrates the difficulty of using probable gene homology as strict indicator of homology between biological structures. PMID:28253300

The Role of Cognitive and Perceptual Loads in Inattentional Deafness

PubMed Central

Causse, Mickaël; Imbert, Jean-Paul; Giraudet, Louise; Jouffrais, Christophe; Tremblay, Sébastien

2016-01-01

The current study examines the role of cognitive and perceptual loads in inattentional deafness (the failure to perceive an auditory stimulus) and the possibility to predict this phenomenon with ocular measurements. Twenty participants performed Air Traffic Control (ATC) scenarios—in the Laby ATC-like microworld—guiding one (low cognitive load) or two (high cognitive load) aircraft while responding to visual notifications related to 7 (low perceptual load) or 21 (high perceptual load) peripheral aircraft. At the same time, participants were played standard tones which they had to ignore (probability = 0.80), or deviant tones (probability = 0.20) which they had to report. Behavioral results showed that 28.76% of alarms were not reported in the low cognitive load condition and up to 46.21% in the high cognitive load condition. On the contrary, perceptual load had no impact on the inattentional deafness rate. Finally, the mean pupil diameter of the fixations that preceded the target tones was significantly lower in the trials in which the participants did not report the tones, likely showing a momentary lapse of sustained attention, which in turn was associated to the occurrence of inattentional deafness. PMID:27458362

Population thiamine status and varying cancer rates between western, Asian and African countries.

PubMed

Boros, L G

2000-01-01

The role of food supplements in the form of vitamins has not been extensively investigated in relation to varying cancer rates between populations of different geographical regions. New data indicate that thiamine (vitamin B1), a common food supplement in Western food products, is directly involved in nucleic acid ribose synthesis of tumor cells in its biologically activated form through the non-oxidative transketolase catalyzed pentose cycle reaction. Whether thiamine plays a role in increased cancer rates in the Western World by enhancing tumor cell proliferation, while increased consumption of thiaminase rich food limiting thiamine availability protects against common malignancies in Asia and Africa has not been evaluated. In the Western World, thiamine is a popular vitamin supplement in the form of tablets and it is also added to basic food items such as milled flour, cereals, peanut butter, refreshment drinks and pastas. On the contrary, thiaminase, the natural thiamine-degrading enzyme, is abundantly present in raw and fermented fish, certain vegetables and roasted insects consumed primarily in Africa and Asia. Excess thiamine supplementation in common food products may contribute to the increased cancer rates of the Western World.

Monitoring peripheral perfusion and microcirculation.

PubMed

Dubin, Arnaldo; Henriquez, Elizabeth; Hernández, Glenn

2018-06-01

Microcirculatory alterations play a major role in the pathogenesis of shock. Monitoring tissue perfusion might be a relevant goal for shock resuscitation. The goal of this review was to revise the evidence supporting the monitoring of peripheral perfusion and microcirculation as goals of resuscitation. For this purpose, we mainly focused on skin perfusion and sublingual microcirculation. Although there are controversies about the reproducibility of capillary refill time in monitoring peripheral perfusion, it is a sound physiological variable and suitable for the ICU settings. In addition, observational studies showed its strong ability to predict outcome. Moreover, a preliminary study suggested that it might be a valuable goal for resuscitation. These results should be confirmed by the ongoing ANDROMEDA-SHOCK randomized controlled trial. On the other hand, the monitoring of sublingual microcirculation might also provide relevant physiological and prognostic information. On the contrary, methodological drawbacks mainly related to video assessment hamper its clinical implementation at the present time. Measurements of peripheral perfusion might be useful as goal of resuscitation. The results of the ANDROMEDA-SHOCK will clarify the role of skin perfusion as a guide for the treatment of shock. In contrast, the assessment of sublingual microcirculation mainly remains as a research tool.

The ethics of medical involvement in torture: commentary

PubMed Central

Hare, R M

1993-01-01

Torture does need to be defined if we are to know exactly what we are seeking to ban; but no single definition will do, because there are many possible ones, and we may want to treat different practices that might be called torture differently. Compare the case of homicide; we do not want to punish manslaughter as severely as murder, and may not want to punish killing in self-defence at all. There are degrees of torture as of murder. Unclarities simply play into the hands of would-be torturers. Downie is unsuccessful in deriving the duty of doctors not to be involved in torture from an analysis of the word `doctor'. It may be contrary to the role-duty of doctors to participate in torture; but there might be other duties which overrode this role-duty. The right approach is to ask what principles for the conduct of doctors have the highest acceptance-utility, or, as Kant might have equivalently put it, what the impartial furtherance of everyone's ends demands. This approach yields the result that torture (suitably defined) should be banned absolutely. It also yields prescriptions for the conduct of doctors where, in spite of them, torture is taking place. PMID:8230144

Comparative analysis on the structural features of the 5' flanking region of κ-casein genes from six different species

PubMed Central

Gerencsér, Ákos; Barta, Endre; Boa, Simon; Kastanis, Petros; Bösze, Zsuzsanna; Whitelaw, C Bruce A

2002-01-01

κ-casein plays an essential role in the formation, stabilisation and aggregation of milk micelles. Control of κ-casein expression reflects this essential role, although an understanding of the mechanisms involved lags behind that of the other milk protein genes. We determined the 5'-flanking sequences for the murine, rabbit and human κ-casein genes and compared them to the published ruminant sequences. The most conserved region was not the proximal promoter region but an approximately 400 bp long region centred 800 bp upstream of the TATA box. This region contained two highly conserved MGF/STAT5 sites with common spacing relative to each other. In this region, six conserved short stretches of similarity were also found which did not correspond to known transcription factor consensus sites. On the contrary to ruminant and human 5' regulatory sequences, the rabbit and murine 5'-flanking regions did not harbour any kind of repetitive elements. We generated a phylogenetic tree of the six species based on multiple alignment of the κ-casein sequences. This study identified conserved candidate transcriptional regulatory elements within the κ-casein gene promoter. PMID:11929628

Largest vertebrate vomeronasal type 1 receptor gene repertoire in the semiaquatic platypus.

PubMed

Grus, Wendy E; Shi, Peng; Zhang, Jianzhi

2007-10-01

Vertebrate vomeronasal chemoreception plays important roles in many aspects of an organism's daily life, such as mating, territoriality, and foraging. Vomeronasal type 1 receptors (V1Rs) and vomeronasal type 2 receptors (V2Rs), 2 large families of G protein-coupled receptors, serve as vomeronasal receptors to bind to various pheromones and odorants. Contrary to the previous observations of reduced olfaction in aquatic and semiaquatic mammals, we here report the surprising finding that the platypus, a semiaquatic monotreme, has the largest V1R repertoire and nearly largest combined repertoire of V1Rs and V2Rs of all vertebrates surveyed, with 270 intact genes and 579 pseudogenes in the V1R family and 15 intact genes, 55 potentially intact genes, and 57 pseudogenes in the V2R family. Phylogenetic analysis shows a remarkable expansion of the V1R repertoire and a moderate expansion of the V2R repertoire in platypus since the separation of monotremes from placentals and marsupials. Our results challenge the view that olfaction is unimportant to aquatic mammals and call for further study into the role of vomeronasal reception in platypus physiology and behavior.

Role of thermal stresses on pulsed laser irradiation of thin films under conditions of microbump formation and nonvaporization forward transfer

NASA Astrophysics Data System (ADS)

Meshcheryakov, Yuri P.; Shugaev, Maxim V.; Mattle, Thomas; Lippert, Thomas; Bulgakova, Nadezhda M.

2013-11-01

This paper presents a theoretical analysis of the processes in thin solid films irradiated by short and ultrashort laser pulses in the regimes of film structuring and laser-induced forward transfer. The regimes are considered at which vaporization of the film materials is insignificant and film dynamics is governed mainly by mechanical processes. Thermoelastoplastic modeling has been performed for a model film in one- and two-dimensional geometries. A method has been proposed to estimate the height of microbumps produced by nanosecond laser irradiation of solid films. Contrary to femtosecond laser pulses, in nanosecond pulse regimes, stress waves across the film are weak and cannot induce film damage. The main role in laser-induced dynamics of irradiated films is played by radial thermal stresses which lead to the formation of a bending wave propagating along the film and drawing the film matter to the center of the irradiation spot. The bending wave dynamics depends on the hardness of the substrate underlying the film. The causes of the receiver substrate damage sometimes observed upon laser-induced forward transfer in the scheme of the direct contact between the film and the receiver are discussed.

The effects of electromagnetic radiation (2450 MHz wireless devices) on the heart and blood tissue: role of melatonin.

PubMed

Gumral, N; Saygin, M; Asci, H; Uguz, A C; Celik, O; Doguc, D K; Savas, H B; Comlekci, S

2016-01-01

This study was designed to investigate the effects of 2450 MHz EMR on the heart and blood in rat and possible ameliorating effects of melatonin. Thirty-two female Wistar Albino rats were randomly grouped (by eight in each group) as follows:  Group I: cage-control group (dimethysulfoxide (DMSO), 10mg/kg/day i.p. without stress and EMR. Group II: sham-control rats stayed in restrainer without EMR and DMSO (10mg/kg/day i.p.). Group III: rats exposed to 2450 MHz EMR. Group IV: treated group rats exposed to 2450 MHz EMR+melatonin (MLT) (10mg/kg/day i.p.). In the blood tissue, there was no significant difference between the groups in respect of erythrocytes GSH, GSH-Px activity, plasma LP level and vitamin A concentration (p > 0.05). However, in the Group IV, erythrocytes' LP levels (p < 0.05) were observed to be significantly decreased while plasma vitamin C, and vitamin E concentrations (p < 0.05) were found to be increased when compared to Group III. In the heart tissues, MDA and NO levels significantly increased in group III compared with groups I and II (p < 0.05). Contrary to these oxidant levels, CAT and SOD enzyme activities decreased significantly in group III compared with groups I and II (p 0.05). Besides, MLT treatment lowered the MDA and NO levels compared with group III. In conclusion, these results demonstrated that contrary to its effect on the heart, the wireless (2450 MHz) devices cause slight oxidative-antioxidative changes in the blood of rats, and a moderate melatonin supplementation may play an important role in the antioxidant system (plasma vitamin C and vitamin E). However, further investigations are required to clarify the mechanism of action of the applied 2450 MHz EMR exposure (Tab. 3, Fig. 1, Ref. 49).

Ingroup favoritism or the black sheep effect: Perceived intentions modulate subjective responses to aggressive interactions.

PubMed

Wang, Lei; Zheng, Jiehui; Meng, Liang; Lu, Qiang; Ma, Qingguo

2016-07-01

Social categorization plays an important role in provoking the victim's responses to aggressive interactions. Pioneering studies suggested that uncertainty in the perpetrator's hostile intention influences whether ingroup favoritism or the black sheep effect (ingroup strictness) will be manifested to a greater extent. However, when the hostile intention is ambiguous, subjective perception of the perpetrator's intention may still be quite different due to the inherent information gap between participants, and this discrepancy in perceived intentions may further modulate subjective responses to social aggression. In the present study, subjects played as responders of the Ultimatum Game, and received varied offers proposed by either ingroup or outgroup members. Electrophysiological results showed that, when proposers were perceived to be intentional, unfair offers from ingroups elicited significantly larger Feedback-related Negativity (FRN) than those from outgroups, potentially providing neural evidence for the black sheep effect. The opposite FRN pattern was observed when proposers were perceived to be unintentional, which might suggest ingroup favoritism. Interestingly, despite contrary neural patterns, perceived intentions did not modulate behavioral response to aggressive interactions. Thus, converging results suggested that, when the perpetrator's hostile intention remained ambiguous, perceived intentions modulated the victim's electrophysiological response while not the rational behavioral response to aggressive interactions. Copyright © 2016 Elsevier Ireland Ltd and Japan Neuroscience Society. All rights reserved.

Genetic data suggest a natural prehuman origin of open habitats in northern Madagascar and question the deforestation narrative in this region.

PubMed

Quéméré, Erwan; Amelot, Xavier; Pierson, Julie; Crouau-Roy, Brigitte; Chikhi, Lounès

2012-08-07

The impact of climate change and anthropogenic deforestation on biodiversity is of growing concern worldwide. Disentangling how past anthropogenic and natural factors contributed to current biome distribution is thus a crucial issue to understand their complex interactions on wider time scales and to improve predictions and conservation strategies. This is particularly important in biodiversity hotspots, such as Madagascar, dominated by large open habitats whose origins are increasingly debated. Although a dominant narrative argues that Madagascar was originally entirely covered by woodlands, which were destroyed by humans, a number of recent studies have suggested that past climatic fluctuations played a major role in shaping current biome distributions well before humans arrived. Here, we address the question of the origin of open habitats in the Daraina region in northern Madagascar, using a multiproxy approach combining population genetics modeling and remote-sensing analyses. We show that (i) contrary to most regions of Madagascar, the forest cover in Daraina remained remarkably stable over the past 60 y, and (ii) the golden-crowned sifaka (Propithecus tattersalli), a forest-dwelling lemur, underwent a strong population contraction before the arrival of the first humans, hence excluding an anthropogenic cause. Prehuman Holocene droughts may have led to a significant increase of grasslands and a reduction in the species' habitat. This contradicts the prevailing narrative that land cover changes are necessarily anthropogenic in Madagascar but does not preclude the later role played by humans in other regions in which recent lemur bottlenecks have been observed.

Effect of lipoic acid and α-glyceryl-phosphoryl-choline on astroglial cell proliferation and differentiation in primary culture.

PubMed

Grasso, S; Bramanti, V; Tomassoni, D; Bronzi, D; Malfa, G; Traini, E; Napoli, M; Renis, M; Amenta, F; Avola, R

2014-01-01

Lipoic acid plays a crucial role as antioxidant and metabolic component of enzymes involved in glucose metabolism of different cell types. Choline alphoscerate (α-glyceryl-phosphoryl-choline [αGPC]) is a semisynthetic derivative of phosphatidylcholines representing, among acetilcholine precursors, a cholinergic drug. In the present study, we evaluated the expression of some proliferation and differentiation markers in 15 or 21 DIV astrocyte cultures treated with 50 μM (+)lipoic acid or (+/-)lipoic acid and/or 10 mM αGPC for 24 hr. In addition, we evaluated the possible genoprotective effect by analysis of DNA status detected by alkaline comet assay. The addition of single drugs [(+)lipoic acid, (+/-)lipoic acid, or αGPC] induced an "upward modulation" of the expression of biomarkers used in our study. On the contrary, the cotreatment with either (+)lipoic acid + αGPC or (+/-)lipoic + αGPC surprisingly showed no significant modification or even a downregulation of the above-mentioned biomarkers. This latter finding demonstrated no additional effect after the cotreatment with both drugs with respect to the single treatments alone. Further studies are necessary to clarify the specific mechanism evoked by the processing of these neuroprotective agents in our in vitro models. Finally, these preliminary findings may represent a good tool with which to clarify the antioxidant and metabolic roles played by lipoic acid in proliferating and differentiating astroglial cell cultures, during an interactive cross-talk between glial and neuronal cells, after brain lesions or damage correlated with oxidative stress that may occur in some degenerative diseases. Copyright © 2013 Wiley Periodicals, Inc.

Do recruitment patterns of young men who have sex with men (YMSM) recruited through respondent-driven sampling (RDS) violate assumptions?

PubMed Central

Phillips, Gregory; Kuhns, Lisa M.; Garofalo, Rob; Mustanski, Brian

2014-01-01

Background In order to generate unbiased estimates for data collected using respondent-driven sampling (RDS), a number of assumptions need to be met: individuals recruit randomly from their social network and people can accurately report their eligible network size. However, research has shown that these assumptions are often violated. Methods This study used baseline data from Crew 450, a longitudinal study of young men who have sex with men in Chicago who were recruited via a modified form of RDS, and its network substudy, in which a subset of 175 participants reported details on the composition and characteristics of their social network at either one or two years post-baseline. Results Nearly two-thirds of participants reported giving coupons to at least one alter (64.0%), and 56.3% believed their alter(s) used the coupons. Frequency of communication, closeness, and type of relationship played a major role in determining coupon distribution. Participants whose alters used coupons were significantly less likely to describe the strength of their relationship as “not at all close” (OR = 0.08; 95% CI: 0.02, 0.36) compared to “very close” and to communicate weekly (OR = 0.20; 95% CI: 0.08, 0.49) or 1–6 times in the last 6 months (OR = 0.18; 95% CI: 0.06, 0.59). Conclusion Contrary to RDS assumptions, we found that relationship characteristics played a significant role when individuals decided to whom they would give coupons. PMID:25086159

Line Mixing in Parallel and Perpendicular Bands of CO2: A Further Test of the Refined Robert-Bonamy Formalism

NASA Technical Reports Server (NTRS)

Boulet, C.; Ma, Qiancheng; Tipping, R. H.

2015-01-01

Starting from the refined Robert-Bonamy formalism [Q. Ma, C. Boulet, and R. H. Tipping, J. Chem. Phys. 139, 034305 (2013)], we propose here an extension of line mixing studies to infrared absorptions of linear polyatomic molecules having stretching and bending modes. The present formalism does not neglect the internal degrees of freedom of the perturbing molecules, contrary to the energy corrected sudden (ECS) modeling, and enables one to calculate the whole relaxation matrix starting from the potential energy surface. Meanwhile, similar to the ECS modeling, the present formalism properly accounts for roles played by all the internal angular momenta in the coupling process, including the vibrational angular momentum. The formalism has been applied to the important case of CO2 broadened by N2. Applications to two kinds of vibrational bands (sigma yields sigma and sigma yields pi) have shown that the present results are in good agreement with both experimental data and results derived from the ECS model.

Biochar alters the resistance and resilience to drought in a tropical soil

NASA Astrophysics Data System (ADS)

Liang, Chenfei; Zhu, Xiaolin; Fu, Shenglei; Méndez, Ana; Gascó, Gabriel; Paz-Ferreiro, Jorge

2014-05-01

Soil microbes play a key role in nutrient cycling and carbon sequestration. Global change can alter soil microbial population composition and behavior. Biochar addition has been explored in the last years as a way to mitigate global warming. However, responses of microbial communities to biochar addition in particular in relation to abiotic disturbances are seldom documented. An example of these disturbances, which is predicted to be exacerbated with global warming, is regional drought. It has been known that fungal-based food webs are more resistant to drought than their bacterial counterparts. Our study found that biochar addition can increase the resistance of both the bacterial and fungal networks to drought. Contrary to expected, this result was not related to a change in the dominance of fungal or bacteria. In general, soil amended with biochar was characterized by a faster recovery of soil microbial properties to its basal values. Biochar addition to the soil also suppressed the Birch effect, a result that has not been previously reported.

Framing effect following bilateral amygdala lesion.

PubMed

Talmi, Deborah; Hurlemann, René; Patin, Alexandra; Dolan, Raymond J

2010-05-01

A paradigmatic example of an emotional bias in decision making is the framing effect, where the manner in which a choice is posed--as a potential loss or a potential gain--systematically biases an ensuing decision. Two fMRI studies have shown that the activation in the amygdala is modulated by the framing effect. Here, contrary to an expectation based on these studies, we show that two patients with Urbach-Wiethe (UW) disease, a rare condition associated with congenital, complete bilateral amygdala degeneration, exhibit an intact framing effect. However, choice preference in these patients did show a qualitatively distinct pattern compared to controls evident in an increased propensity to gamble, indicating that loss of amygdala function does exert an overall influence on risk-taking. These findings suggest either that amygdala does contribute to decision making but does not play a causal role in framing, or that UW is not a pure lesion model of amygdala function. 2010 Elsevier Ltd. All rights reserved.

Epitaxial Ge2Sb2Te5 probed by single cycle THz pulses of coherent synchrotron radiation

NASA Astrophysics Data System (ADS)

Bragaglia, V.; Schnegg, A.; Calarco, R.; Holldack, K.

2016-10-01

A THz-probe spectroscopy scheme with laser-induced single cycle pulses of coherent synchrotron radiation is devised and adapted to reveal the dynamic THz transmittance response in epitaxially grown phase change materials upon 800 nm fs-laser excitation. Amorphous (a-) and crystalline (c-) films of the prototypical Ge2Sb2Te5 (GST) alloy are probed with single cycle THz pulses tuned to the spectral range of the highest absorption contrast at 2 THz. After an initial instantaneous sub-picosecond (ps) dynamic THz transmittance drop, the response of a-GST in that range is dominated only by a short recovery time τshort = 2 ps of the excited carriers. On the contrary, the behavior of the c-GST response displays a short decay of 0.85 ps followed by a long one τlong = 90 ps, suggesting that vacancy layers in an ordered c-GST play a role as dissipation channel for photo-induced free carriers.

Functional topography of single cortical cells: an intracellular approach combined with optical imaging.

PubMed

Buzás, P; Eysel, U T; Kisvárday, Z F

1998-11-01

Pyramidal cells mediating long-range corticocortical connections have been assumed to play an important role in visual perceptual mechanisms [C.D. Gilbert, Horizontal integration and cortical dynamics, Neuron 9 (1992) 1-13]. However, no information is available as yet on the specificity of individual pyramidal cells with respect to functional maps, e.g., orientation map. Here, we show a combination of techniques with which the functional topography of single pyramidal neurons can be explored in utmost detail. To this end, we used optical imaging of intrinsic signals followed by intracellular recording and staining with biocytin in vivo. The axonal and dendritic trees of the labelled neurons were reconstructed in three dimensions and aligned with corresponding functional orientation maps. The results indicate that, contrary to the sharp orientation tuning of neurons shown by the recorded spike activity, the efferent connections (axon terminal distribution) of the same pyramidal cells were found to terminate at a much broader range of orientations. Copyright 1998 Elsevier Science B.V.

Silicon nanofin grating as a miniature chirality-distinguishing beam-splitter.

PubMed

Khorasaninejad, Mohammadreza; Crozier, Kenneth B

2014-11-12

The polarization of light plays a central role in its interaction with matter, in situations ranging from familiar (for example, reflection and transmission at an interface) to sophisticated (for example, nonlinear optics). Polarization control is therefore pivotal for many optical systems, and achieved using bulk devices such as wave-plates and beam-splitters. The move towards optical system miniaturization therefore motivates the development of micro- and nanostructures for polarization control. For such control to be complete, one must distinguish not only between linear polarizations, but also between left- and right-circular polarizations. Some previous works used surface plasmons to this end, but these are inherently lossy. Other works used complex-layered structures. Here we demonstrate a planar dielectric chirality-distinguishing beam-splitter. The beam-splitter consists of amorphous silicon nanofins on a glass substrate and deflects left- and right-circularly polarized beams into different directions. Contrary to intuitive expectations, we utilize an achiral architecture to realize a chiral beam-splitting functionality.

High Resolution Studies Of Lensed z ∼ 2 Galaxies: Kinematics And Metal Gradients

NASA Astrophysics Data System (ADS)

Leethochawalit, Nicha

2016-09-01

We use the OSIRIS integral field unit (IFU) spectograph to secure spatially-resolved strong emission lines of 15 gravitationally-lensed star-forming galaxies at redshift z ∼ 2. With the aid of gravitational lensing and Keck laser-assisted adaptive optics, the spatial resolution of these sub-luminous galaxies is at a few hundred parsecs. First, we demonstrate that high spatial resolution is crucial in diagnosing the kinematic properties and dynamical maturity of z ∼ 2 galaxies. We observe a significantly lower fraction of rotationally-supported systems than what has been claimed in lower spatial resolution surveys. Second, we find a much larger fraction of z ∼ 2 galaxies with weak metallicity gradients, contrary to the simple picture suggested by earlier studies that well-ordered rotation develops concurrently with established steep metal gradients in all but merging systems. Comparing our observations with the predictions of hydronamical simulations, strong feedback is likely to play a key role in flattening metal gradients in early star-forming galaxies.

Modes of transmission of Simian T-lymphotropic Virus Type 1 in semi-captive mandrills (Mandrillus sphinx).

PubMed

Roussel, Marion; Pontier, Dominique; Ngoubangoye, Barthélémy; Kazanji, Mirdad; Verrier, Delphine; Fouchet, David

2015-09-30

Non-human primates (NHPs) often live in inaccessible areas, have cryptic behaviors, and are difficult to follow in the wild. Here, we present a study on the spread of the simian T-lymphotropic Virus Type 1 (STLV-1), the simian counterpart of the human T-lymphotropic virus type 1 (HTLV-1) in a semi-captive mandrill colony. This study combines 28 years of longitudinal monitoring, including behavioral data, with a dynamic mathematical model and Bayesian inference. Three transmission modes were suspected: aggressive, sexual and familial. Our results show that among males, STLV-1 transmission occurs preferentially via aggression. Because of their impressive aggressive behavior male mandrills can easily transmit the virus during fights. On the contrary, sexual activity seems to have little effect. Thus transmission appears to occur primarily via male-male and female-female contact. In addition, for young mandrills, familial transmission appears to play an important role in virus spread. Copyright © 2015 Elsevier B.V. All rights reserved.

[The microbial flora in the digestive tract and diabetes].

PubMed

Svačina, Štěpán

2015-04-01

The microbial flora in the digestive tract has been recently studied in relation to metabolic diseases. There are relations to both type 1 diabetes and type 2 diabetes. The intestinal flora is affected by diet, physical exercise and it significantly changes after bariatric surgeries. Giving birth by caesarean section affects the gut flora development and increases the risk of type 1 diabetes in further life of the child. Obese patients with type 2 diabetes may lack protective microbes which improve glucoregulation in the experiment or on the contrary their patogenous microbes may grow which have been proven to even be able to penetrate into abdominal adipose tissue and play a role, inter alia, in the hepatic impairment and systemic inflammation. Also vaccination against these microbes is under consideration. Microbiome can be also positively affected by metformin treatment. The transfer of intestinal flora by means of fecal transplantation can improve glucoregulation. The influencing of intestinal flora is likely to become a new mechanism of diabetes treatment.

Pronounced Environmental Effects on Injection Currents in EGaIn Tunneling Junctions Comprising Self-Assembled Monolayers.

PubMed

Carlotti, Marco; Degen, Maarten; Zhang, Yanxi; Chiechi, Ryan C

2016-09-15

Large-area tunneling junctions using eutectic Ga-In (EGaIn) as a top contact have proven to be a robust, reproducible, and technologically relevant platform for molecular electronics. Thus far, the majority of studies have focused on saturated molecules with backbones consisting mainly of alkanes in which the frontier orbitals are either highly localized or energetically inaccessible. We show that self-assembled monolayers of wire-like oligophenyleneethynylenes (OPEs), which are fully conjugated, only exhibit length-dependent tunneling behavior in a low-O 2 environment. We attribute this unexpected behavior to the sensitivity of injection current on environment. We conclude that, contrary to previous reports, the self-limiting layer of Ga 2 O 3 strongly influences transport properties and that the effect is related to the wetting behavior of the electrode. This result sheds light on the nature of the electrode-molecule interface and suggests that adhesive forces play a significant role in tunneling charge-transport in large-area molecular junctions.

Realistic Clocks for a Universe Without Time

NASA Astrophysics Data System (ADS)

Bryan, K. L. H.; Medved, A. J. M.

2018-01-01

There are a number of problematic features within the current treatment of time in physical theories, including the "timelessness" of the Universe as encapsulated by the Wheeler-DeWitt equation. This paper considers one particular investigation into resolving this issue; a conditional probability interpretation that was first proposed by Page and Wooters. Those authors addressed the apparent timelessness by subdividing a faux Universe into two entangled parts, "the clock" and "the remainder of the Universe", and then synchronizing the effective dynamics of the two subsystems by way of conditional probabilities. The current treatment focuses on the possibility of using a (somewhat) realistic clock system; namely, a coherent-state description of a damped harmonic oscillator. This clock proves to be consistent with the conditional probability interpretation; in particular, a standard evolution operator is identified with the position of the clock playing the role of time for the rest of the Universe. Restrictions on the damping factor are determined and, perhaps contrary to expectations, the optimal choice of clock is not necessarily one of minimal damping.

Influence of Soil Factors on the Stereoselective Fate of a Novel Chiral Insecticide, Paichongding, in Flooded Paddy Soils.

PubMed

Li, Juying; Huang, Tuo; Li, Lizong; Ding, Tengda; Zhu, Hong; Yang, Bo; Ye, Qingfu; Gan, Jay

2016-11-02

In this study, the fate of paichongding was investigated in three soils with contrasting soil properties. In general, low soil pH has the potential to retard the mineralization and promote the dissipation of paichongding and the formation of its primary transformation product and to accelerate the formation of bound residue. The dissipation of paichongding stereoisomers was very fast and diastereoselective. This selectivity was found only between diastereomers and not between enantiomers and was observed to be soil dependent. In the acidic soil, the enantiomers (5R,7R)- and (5S,7S)-paichongding were degraded more quickly than (5R,7S)- and (5S,7R)-paichongding, whereas a contrary trend was observed in the neutral soil, and such selectivity did not occur in the alkaline soil. The OM and clay contents also played important roles in the fate of paichongding. This effect of soil properties should be considered in risk assessment of chiral pesticides and their application in the field.

Beyond Faces and Expertise

PubMed Central

Zhao, Mintao; Bülthoff, Heinrich H.; Bülthoff, Isabelle

2016-01-01

Holistic processing—the tendency to perceive objects as indecomposable wholes—has long been viewed as a process specific to faces or objects of expertise. Although current theories differ in what causes holistic processing, they share a fundamental constraint for its generalization: Nonface objects cannot elicit facelike holistic processing in the absence of expertise. Contrary to this prevailing view, here we show that line patterns with salient Gestalt information (i.e., connectedness, closure, and continuity between parts) can be processed as holistically as faces without any training. Moreover, weakening the saliency of Gestalt information in these patterns reduced holistic processing of them, which indicates that Gestalt information plays a crucial role in holistic processing. Therefore, holistic processing can be achieved not only via a top-down route based on expertise, but also via a bottom-up route relying merely on object-based information. The finding that facelike holistic processing can extend beyond the domains of faces and objects of expertise poses a challenge to current dominant theories. PMID:26674129

The cold response of CBF genes in barley is regulated by distinct signaling mechanisms.

PubMed

Marozsán-Tóth, Zsuzsa; Vashegyi, Ildikó; Galiba, Gábor; Tóth, Balázs

2015-06-01

Cold acclimation ability is crucial in the winter survival of cereals. In this process CBF transcription factors play key role, therefore understanding the regulation of these genes might provide useful knowledge for molecular breeding. In the present study the signal transduction pathways leading to the cold induction of different CBF genes were investigated in barley cv. Nure using pharmacological approach. Our results showed that the cold induced expression of CBF9 and CBF14 transcription factors is regulated by phospholipase C, phospholipase D pathways and calcium. On the contrary, these pathways have negative effect on the cold induction of CBF12 that is regulated by a different, as yet unidentified pathway. The diversity in the regulation of these transcription factors corresponds to their sequence based phylogenetic relationships suggesting that their evolutionary separation happened on structural, functional and regulational levels as well. On the CBF effector gene level, the signaling regulation is more complex, resultant effect of multiple pathways. Copyright © 2015 Elsevier GmbH. All rights reserved.

Microtubule assembly governed by tubulin allosteric gain in flexibility and lattice induced fit

PubMed Central

2018-01-01

Microtubules (MTs) are key components of the cytoskeleton and play a central role in cell division and development. MT assembly is known to be associated with a structural change in αβ-tubulin dimers from kinked to straight conformations. How GTP binding renders individual dimers polymerization-competent, however, is still unclear. Here, we have characterized the conformational dynamics and energetics of unassembled tubulin using atomistic molecular dynamics and free energy calculations. Contrary to existing allosteric and lattice models, we find that GTP-tubulin favors a broad range of almost isoenergetic curvatures, whereas GDP-tubulin has a much lower bending flexibility. Moreover, irrespective of the bound nucleotide and curvature, two conformational states exist differing in location of the anchor point connecting the monomers that affects tubulin bending, with one state being strongly favored in solution. Our findings suggest a new combined model in which MTs incorporate and stabilize flexible GTP-dimers with a specific anchor point state. PMID:29652248

Mastitis treatment-Reduction in antibiotic usage in dairy cows.

PubMed

Krömker, V; Leimbach, S

2017-08-01

Animal-friendly, economical, resource-saving milk production provides the basis for sustained consumer acceptance. Bovine mastitis plays a decisive role in the dairy industry-disturbing animal health and welfare and causing considerable economic losses on the other hand. Currently, antimicrobial treatment is indispensable to keep bovine udder health, animal welfare and economic aspects in balance. On the contrary, emergence and spread of antimicrobial resistance (AMR) is an urgent matter of particular public interest, and as a consequence, antimicrobial usage (AMU) in production livestock is a critically discussed subject. In urgent need of future reduction in AMU in the dairy industry, this review article describes and discusses possible approaches promising prompt implementation, including therapeutical alternatives as well as pro- and metaphylactic concepts such as the implementation of evidence-based mastitis therapy concepts and selective dry cow treatment (sDCT), in search of the most effective and contemporary methods for decreasing AMU and AMR in dairy production. © 2017 Blackwell Verlag GmbH.

Fine-scale analysis of genetic structure in the brooding coral Seriatopora hystrix from the Red Sea

NASA Astrophysics Data System (ADS)

Maier, E.; Tollrian, R.; Nürnberger, B.

2009-09-01

The dispersal of gametes and larvae plays a key role in the population dynamics of sessile marine invertebrates. Species with internal fertilisation are often associated with very localised larval dispersal, which may cause small-scale patterns of neutral genetic variation. This study on the brooding coral Seriatopora hystrix from the Red Sea focused on the smallest possible scale: Two S. hystrix stands (~100 colonies each) near Dahab were completely sampled, mapped and analysed at five microsatellite markers. The sexual mode of reproduction, the likely occurrence of selfing and the level of immigration were in agreement with previous studies on this species. Contrary to previous findings, both stands were in Hardy-Weinberg proportions. Also, no evidence for spatially restricted larval dispersal within the sampled areas was found. Differences between this and previous studies on S. hystrix could reflect variation in life history or varying environmental conditions, which opens intriguing questions for future research.

Recruitment and establishment of the gut microbiome in arctic shorebirds.

PubMed

Grond, Kirsten; Lanctot, Richard B; Jumpponen, Ari; Sandercock, Brett K

2017-12-01

Gut microbiota play a key role in host health. Mammals acquire gut microbiota during birth, but timing of gut microbial recruitment in birds is unknown. We evaluated whether precocial chicks from three species of arctic-breeding shorebirds acquire gut microbiota before or after hatching, and then documented the rate and compositional dynamics of accumulation of gut microbiota. Contrary to earlier reports of microbial recruitment before hatching in chickens, quantitative PCR and Illumina sequence data indicated negligible microbiota in the guts of shorebird embryos before hatching. Analyses of chick feces indicated an exponential increase in bacterial abundance of guts 0-2 days post-hatch, followed by stabilization. Gut communities were characterized by stochastic recruitment and convergence towards a community dominated by Clostridia and Gammaproteobacteria. We conclude that guts of shorebird chicks are likely void of microbiota prior to hatch, but that stable gut microbiome establishes as early as 3 days of age, probably from environmental inocula. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Assessment of PTSD symptoms in emergency room, intensive care unit, and general floor nurses.

PubMed

Kerasiotis, Bernadina; Motta, Robert W

2004-01-01

A total of 125 registered nurses participated in an investigation of Posttraumatic Stress Disorder (PTSD) related symptoms and various levels of nursing care. The sample included 43 emergency room nurses (ER), 51 intensive care unit nurses (ICU), and 31 general floor nurses (GF). All participants were assessed on measures of PTSD, social support, dissociation, anxiety, depression, and demographics. Contrary to expectations, the ER nurses were not found to be uniquely stressed by their work when compared to the other nursing groups. Results indicated that all nurses experienced a significant level of anxiety but were not in the clinically significant range for PTSD, depression, or dissociation. It was inferred that social support played a significant role in helping nurses cope with work-related stress. Nevertheless, the high anxiety levels of all nurses were highlighted as a concern. It was suggested that exposure to numerous traumatic experiences over a lifetime of nursing, and a lack of control over these experiences, contributed to the high anxiety levels seen in all nursing groups.

The effect of high pressure on the lattice structure and dynamics of phenacenes

NASA Astrophysics Data System (ADS)

Capitani, F.; Höppner, M.; Malavasi, L.; Marini, C.; Dore, P.; Boeri, L.; Postorino, Paolo

2017-10-01

We studied the effect of high pressure on three phenacenes, aromatic molecules with a zig-zag configuration of the benzene rings. The lattice structure and vibrational dynamics of crystalline phenanthrene (C14H10, three benzene rings), chrysene (C18H12, four), and picene (C22H14, five) were investigated by means of X-ray diffraction and Raman measurements. Raman spectra were compared with theoretical ones obtained from ab-initio Density Functional Theory calculations. Experimental and theoretical results allowed to identify the onset of a structural transition in phenanthrene at 7.8 GPa under hydrostatic conditions and at 5.7 GPa under non-hydrostatic conditions. We found that this transition is related to a reorientantion of the molecules in the ab plane. On the contrary, chrysene and picene do not undergo any phase transition in the investigated pressure range, thus suggesting that molecular size plays an important role in the occurence of pressure induced structural modifications in aromatic compounds.

Pronounced Environmental Effects on Injection Currents in EGaIn Tunneling Junctions Comprising Self-Assembled Monolayers

PubMed Central

2016-01-01

Large-area tunneling junctions using eutectic Ga–In (EGaIn) as a top contact have proven to be a robust, reproducible, and technologically relevant platform for molecular electronics. Thus far, the majority of studies have focused on saturated molecules with backbones consisting mainly of alkanes in which the frontier orbitals are either highly localized or energetically inaccessible. We show that self-assembled monolayers of wire-like oligophenyleneethynylenes (OPEs), which are fully conjugated, only exhibit length-dependent tunneling behavior in a low-O2 environment. We attribute this unexpected behavior to the sensitivity of injection current on environment. We conclude that, contrary to previous reports, the self-limiting layer of Ga2O3 strongly influences transport properties and that the effect is related to the wetting behavior of the electrode. This result sheds light on the nature of the electrode–molecule interface and suggests that adhesive forces play a significant role in tunneling charge-transport in large-area molecular junctions. PMID:27738488

They call it like they see it: spontaneous naming and attention to shape.

PubMed

Samuelson, Larissa K; Smith, Linda B

2005-03-01

Two experiments explore children's spontaneous labeling of novel objects as a method to study early lexical access. The experiments also provide new evidence on children's attention to object shape when labeling objects. In Experiment 1, the spontaneous productions of 21 23- to 28-month-olds (mean 26;28) shown a set of novel, unnamed objects were analyzed both in terms of the specific words said and, via adult judgments, their likely perceptual basis. We found that children's spontaneous names were cued by the perceptual feature of shape. Experiment 2 examines the relation between spontaneous productions, name generalizations in a structured task, and vocabulary development in a group of children between 17 and 24 months of age (mean 21;6). Results indicate that object shape plays an important role in both spontaneous productions and novel noun generalization, but contrary to current hypotheses, children may name objects by shape from the earliest points of productive vocabulary development and this tendency may not be lexically specific.

Communities as cliques

PubMed Central

Fried, Yael; Kessler, David A.; Shnerb, Nadav M.

2016-01-01

High-diversity species assemblages are very common in nature, and yet the factors allowing for the maintenance of biodiversity remain obscure. The competitive exclusion principle and May’s complexity-diversity puzzle both suggest that a community can support only a small number of species, turning the spotlight on the dynamics of local patches or islands, where stable and uninvadable (SU) subsets of species play a crucial role. Here we map the question of the number of different possible SUs a community can support to the geometric problem of finding maximal cliques of the corresponding graph. This enables us to solve for the number of SUs as a function of the species richness in the regional pool, N, showing that the growth of this number is subexponential in N, contrary to long-standing wisdom. To understand the dynamics under noise we examine the relaxation time to an SU. Symmetric systems relax rapidly, whereas in asymmetric systems the relaxation time grows much faster with N, suggesting an excitable dynamics under noise. PMID:27759102

Numerical analysis of helical dielectric elastomer actuator

NASA Astrophysics Data System (ADS)

Park, Jang Ho; Nair, Saurabh; Kim, Daewon

2017-04-01

Dielectric elastomer actuators (DEA) are known for its capability of experiencing extreme strains, as it can expand and contract based on specific actuation voltage applied. On contrary, helical DEA (HDEA) with its unique configuration does not only provide the contractile and extendable capabilities, but also can aid in attaining results for bending and torsion. The concept of HDEA embraces many new techniques and can be applied in multiple disciplines. Thus, this paper focuses on the simulation of HDEA with helical compliant electrodes that is a major factor prior to its application. The attributes of the material used to build the structure plays a vital role in the behavior of the system. For numerical analysis of HDEA, the material characteristics are input into a commercial grade software, and then the appropriate analysis is performed to retrieve its outcome. Applying the material characteristics into numerical analysis modeling, the functionality of HDEA for various activations can be achieved, which is used to test and comply with the fabricated final product.

Maxwell and the normal distribution: A colored story of probability, independence, and tendency toward equilibrium

NASA Astrophysics Data System (ADS)

Gyenis, Balázs

2017-02-01

We investigate Maxwell's attempt to justify the mathematical assumptions behind his 1860 Proposition IV according to which the velocity components of colliding particles follow the normal distribution. Contrary to the commonly held view we find that his molecular collision model plays a crucial role in reaching this conclusion, and that his model assumptions also permit inference to equalization of mean kinetic energies (temperatures), which is what he intended to prove in his discredited and widely ignored Proposition VI. If we take a charitable reading of his own proof of Proposition VI then it was Maxwell, and not Boltzmann, who gave the first proof of a tendency towards equilibrium, a sort of H-theorem. We also call attention to a potential conflation of notions of probabilistic and value independence in relevant prior works of his contemporaries and of his own, and argue that this conflation might have impacted his adoption of the suspect independence assumption of Proposition IV.

AC conduction of Ba1-xCaxTiO3 and BZT-BCTx

NASA Astrophysics Data System (ADS)

Khien, Nguyen Van; Huy, Than Trong; Hong, Le Van

2018-03-01

Ba1-xCaxTiO3 (BCTx), (x =0.0-0.3) and Ba0.8Zr0.2TiO3-Ba1-xCaxTiO3 (BZT-BCTx), (x=0.15-0.35) were fabricated by the solid state reaction method. Phase structure of the material samples was identified by X-ray diffraction. The impedance versus frequency in a range of 100 Hz to 2.5 MHz was measured for all the samples at room temperature. AC conductivity versus frequency of the BCTx and BZT-BCTx was evaluated and fitted by using the extended Universal Dielectric Response (UDR) equations. The fitting results were discussed in detail and shown that the localized reorientation polarization-based mechanism is most contributed in BCTx matrial samples. Basically both two the hopping polaron and polarization mechanisms play roles in BZT-BCTx material samples. In contrary the short-range polaron hopping is dominated in ac conductivity of BZT-BCTx material samples in low frequency range.

Antitumoural Sulphur and Selenium Heteroaryl Compounds: Thermal Characterization and Stability Evaluation.

PubMed

Alcolea, Verónica; Garnica, Pablo; Palop, Juan A; Sanmartín, Carmen; González-Peñas, Elena; Durán, Adrián; Lizarraga, Elena

2017-08-08

The physicochemical properties of a compound play a crucial role in the cancer development process. In this context, polymorphism can become an important obstacle for the pharmaceutical industry because it frequently leads to the loss of therapeutic effectiveness of some drugs. Stability under manufacturing conditions is also critical to ensure no undesired degradations or transformations occur. In this study, the thermal behaviour of 40 derivatives of a series of sulphur and selenium heteroaryl compounds with potential antitumoural activity were studied. In addition, the most promising cytotoxic derivatives were analysed by a combination of differential scanning calorimetry, X-ray diffraction and thermogravimetric techniques in order to investigate their polymorphism and thermal stability. Moreover, stability under acid, alkaline and oxidative media was tested. Degradation under stress conditions as well as the presence of polymorphism was found for the compounds VA6E and VA7J, which might present a hurdle to carrying on with formulation. On the contrary, these obstacles were not found for derivative VA4J.

Domain wall dynamics along curved strips under current pulses: The influence of Joule heating

NASA Astrophysics Data System (ADS)

Raposo, Victor; Moretti, Simone; Hernandez, Maria Auxiliadora; Martinez, Eduardo

2016-01-01

The current-induced domain wall dynamics along curved ferromagnetic strips is studied by coupling the magnetization dynamics to the heat transport. Permalloy strips with uniform and non-uniform cross section are evaluated, taking into account the influence of the electrical contacts used to inject the current pulses and the substrate on top of which the ferromagnetic strip is sited. Micromagnetic simulations indicate that the geometry and the non-ferromagnetic materials in the system play a significant role in the current-induced domain wall dynamics. Due to the natural pinning, domain walls are hardly affected by the spin-transfer torques when placed in uniform cross section strips under current pulses with reduced magnitude. On the contrary, the current-induced domain wall displacement is significantly different in strips with non-uniform cross section, where thermal gradients emerge as due to the Joule heating. It is found that these thermal gradients can assist or act against the pure spin-transfer torques, in agreement with the recent experimental observations.

Natural derivatives of diphenolic acid as substitutes for bisphenol-A

NASA Astrophysics Data System (ADS)

Ertl, Johanna; Cerri, Elisa; Rizzuto, Matteo; Caretti, Daniele

2014-05-01

Diphenolic acid had been originally used in the first epoxy resins and was later on forgotten as it was substituted by the cheaper bisphenol A. But in the recent years major health concerns have been raised as bisphenol A has a pseudo-hormonal effect on the body, playing the role of estrogen it can cause a severe impact on the organism, especially in males. Moreover it is produced from acetone and phenol, both from fossil, and thus limited resources. On the contrary, diphenolic acid is synthesized from levulinic acid and phenol. Levulinic acid being directly produced by hydrolysis of biomass. By substituting the fossil phenol with natural phenols from lignin or plant extraction we are able to synthesize a fully renewable substitute for bisphenol A. The reactions to yield an epoxy resin have been examined and the reactivity with epichlorohydrin is satisfying. Moreover, some of the derivatives of diphenolic acid have interesting curing properties and preliminary results show excellent properties of the cured resin, including thermal stability and pencil hardness.

Analysis of the effects of early nutritional environment on inbreeding depression in Drosophila melanogaster.

PubMed

Valtonen, T M; Roff, D A; Rantala, M J

2011-01-01

The impact of nutritional deficiencies early in life in determining life-history variation in organisms is well recognized. The negative effects of inbreeding on fitness are also well known. Contrary to studies on vertebrates, studies on invertebrates are not consistent with the observation that inbreeding compromises resistance to parasites and pathogens. In this study, we investigated the effect of early nutrition on the magnitude of inbreeding depression in development time, adult body size and adult resistance to the bacterium Serratia marcescens in Drosophila melanogaster. We found that early nutritional environment had no effect on the magnitude of inbreeding depression in development time or adult body size but may have played a small role in adult resistance to the bacterial infection. Estimates of heritabilities for development time under the poor nutritional environment were larger than those measured under the standard nutritional conditions. © 2010 The Authors. Journal of Evolutionary Biology © 2010 European Society For Evolutionary Biology.

Liquid-Gas-Like Phase Transition in Sand Flow Under Microgravity

NASA Astrophysics Data System (ADS)

Huang, Yu; Zhu, Chongqiang; Xiang, Xiang; Mao, Wuwei

2015-06-01

In previous studies of granular flow, it has been found that gravity plays a compacting role, causing convection and stratification by density. However, there is a lack of research and analysis of the characteristics of different particles' motion under normal gravity contrary to microgravity. In this paper, we conduct model experiments on sand flow using a model test system based on a drop tower under microgravity, within which the characteristics and development processes of granular flow under microgravity are captured by high-speed cameras. The configurations of granular flow are simulated using a modified MPS (moving particle simulation), which is a mesh-free, pure Lagrangian method. Moreover, liquid-gas-like phase transitions in the sand flow under microgravity, including the transitions to "escaped", "jumping", and "scattered" particles are highlighted, and their effects on the weakening of shear resistance, enhancement of fluidization, and changes in particle-wall and particle-particle contact mode are analyzed. This study could help explain the surface geology evolution of small solar bodies and elucidate the nature of granular interaction.

Comparative analysis of plant use in peri-urban domestic gardens of the Limpopo Province, South Africa

PubMed Central

2014-01-01

Background Relatively little has been researched or published on the importance of peri-urban domestic gardens as part of a household livelihood strategy in South Africa. Due to lack of comprehensive data on peri-urban domestic gardens, their potential value as luxury green space, provision of food, income and ecosystem services to the fast growing urban population in South Africa is not clearly known. The aim of this study was to document differences and similarities in plant use and diversity in domestic gardens of two peri-urban communities in the Limpopo Province that differ in proximity to an urban area. Methods Data on plant use categories of 62 domestic gardens in the peri-urban areas of the Limpopo Province were collected in Seshego and Lebowakgomo. Semi-structured interviews, observation and guided field walks with 62 participants were employed between May and October 2012. Results A total of 126 plant species were recorded for both Seshego and Lebowakgomo. Domestic gardens in the more remote areas of Lebowakgomo were characterized by higher percentage of food plants (47 species, 83.8% of the total food plants recorded) and medicinal plants (31 species, 83.7%). Lebowakgomo domestic gardens were also characterized by higher numbers of indigenous plants (76.7%) showing similarities to the natural surrounding vegetation in terms of plant species. On the contrary, domestic gardens of Seshego on the periphery of the city centre were characterized by higher percentage of exotic species (81.8%) and ornamental plants (73%), with food plants playing a supplementary role. Comparison of the two areas demonstrated a remarkable difference in plant use and composition. Conclusions This study revealed that there are differences in utilization of plant resources between households on the edge of an urban centre and those in the more remote areas. Food and medicinal plants play an important role in remote areas; while ornamental plants play an important role in urban domestic gardens. But the collective desire for food, medicinal and ornamental plants by both communities on the edge of an urban centre and those in the more remote areas highlight the importance of plant resources in domestic gardens. PMID:24708756

The tarantula toxins ProTx-II and huwentoxin-IV differentially interact with human Nav1.7 voltage sensors to inhibit channel activation and inactivation.

PubMed

Xiao, Yucheng; Blumenthal, Kenneth; Jackson, James O; Liang, Songping; Cummins, Theodore R

2010-12-01

The voltage-gated sodium channel Na(v)1.7 plays a crucial role in pain, and drugs that inhibit hNa(v)1.7 may have tremendous therapeutic potential. ProTx-II and huwentoxin-IV (HWTX-IV), cystine knot peptides from tarantula venoms, preferentially block hNa(v)1.7. Understanding the interactions of these toxins with sodium channels could aid the development of novel pain therapeutics. Whereas both ProTx-II and HWTX-IV have been proposed to preferentially block hNa(v)1.7 activation by trapping the domain II voltage-sensor in the resting configuration, we show that specific residues in the voltage-sensor paddle of domain II play substantially different roles in determining the affinities of these toxins to hNa(v)1.7. The mutation E818C increases ProTx-II's and HWTX-IV's IC(50) for block of hNa(v)1.7 currents by 4- and 400-fold, respectively. In contrast, the mutation F813G decreases ProTx-II affinity by 9-fold but has no effect on HWTX-IV affinity. It is noteworthy that we also show that ProTx-II, but not HWTX-IV, preferentially interacts with hNa(v)1.7 to impede fast inactivation by trapping the domain IV voltage-sensor in the resting configuration. Mutations E1589Q and T1590K in domain IV each decreased ProTx-II's IC(50) for impairment of fast inactivation by ~6-fold. In contrast mutations D1586A and F1592A in domain-IV increased ProTx-II's IC(50) for impairment of fast inactivation by ~4-fold. Our results show that whereas ProTx-II and HWTX-IV binding determinants on domain-II may overlap, domain II plays a much more crucial role for HWTX-IV, and contrary to what has been proposed to be a guiding principle of sodium channel pharmacology, molecules do not have to exclusively target the domain IV voltage-sensor to influence sodium channel inactivation.

Vitamin D deficiency: a new risk factor for type 2 diabetes?.

PubMed

Mezza, T; Muscogiuri, G; Sorice, G P; Prioletta, A; Salomone, E; Pontecorvi, A; Giaccari, A

2012-01-01

Recent compelling evidence suggests a role of vitamin D deficiency in the pathogenesis of insulin resistance and insulin secretion derangements, with a consequent possible interference with type 2 diabetes mellitus. The mechanism of this link is incompletely understood. In fact, vitamin D deficiency is usually detected in obesity in which insulin resistance is also a common finding. The coexistence of insulin resistance and vitamin D deficiency has generated several hypotheses. Some cross-sectional and prospective studies have suggested that vitamin D deficiency may play a role in worsening insulin resistance; others have identified obesity as a risk factor predisposing individuals to exhibit both vitamin D deficiency and insulin resistance. The available data from intervention studies are largely confounded, and inadequate considerations of seasonal effects on 25(OH)D concentrations are also a common design flaw in many studies. On the contrary, there is strong evidence that obesity might cause both vitamin D deficiency and insulin resistance, leaving open the possibility that vitamin D and diabetes are not related at all. Although it might seem premature to draw firm conclusions on the role of vitamin D supplementation in reducing insulin resistance and preventing type 2 diabetes, this manuscript will review the circumstances leading to vitamin D deficiency and how such a deficiency can eventually independently affect insulin sensitivity. Copyright © 2012 S. Karger AG, Basel.

Two Cassava Basic Leucine Zipper (bZIP) Transcription Factors (MebZIP3 and MebZIP5) Confer Disease Resistance against Cassava Bacterial Blight.

PubMed

Li, Xiaolin; Fan, Shuhong; Hu, Wei; Liu, Guoyin; Wei, Yunxie; He, Chaozu; Shi, Haitao

2017-01-01

Basic domain-leucine zipper (bZIP) transcription factor, one type of conserved gene family, plays an important role in plant development and stress responses. Although 77 MebZIPs have been genome-wide identified in cassava, their in vivo roles remain unknown. In this study, we analyzed the expression pattern and the function of two MebZIPs ( MebZIP3 and MebZIP5 ) in response to pathogen infection. Gene expression analysis indicated that MebZIP3 and MebZIP5 were commonly regulated by flg22, Xanthomonas axonopodis pv. manihotis ( Xam ), salicylic acid (SA), and hydrogen peroxide (H 2 O 2 ). Subcellular localization analysis showed that MebZIP3 and MebZIP5 are specifically located in cell nucleus. Through overexpression in tobacco, we found that MebZIP3 and MebZIP5 conferred improved disease resistance against cassava bacterial blight, with more callose depositions. On the contrary, MebZIP3- and MebZIP5 -silenced plants by virus-induced gene silencing (VIGS) showed disease sensitive phenotype, lower transcript levels of defense-related genes and less callose depositions. Taken together, this study highlights the positive role of MebZIP3 and MebZIP5 in disease resistance against cassava bacterial blight for further utilization in genetic improvement of cassava disease resistance.

Neuronal somatic ATP release triggers neuron–satellite glial cell communication in dorsal root ganglia

PubMed Central

Zhang, X.; Chen, Y.; Wang, C.; Huang, L.-Y. M.

2007-01-01

It has been generally assumed that the cell body (soma) of a neuron, which contains the nucleus, is mainly responsible for synthesis of macromolecules and has a limited role in cell-to-cell communication. Using sniffer patch recordings, we show here that electrical stimulation of dorsal root ganglion (DRG) neurons elicits robust vesicular ATP release from their somata. The rate of release events increases with the frequency of nerve stimulation; external Ca2+ entry is required for the release. FM1–43 photoconversion analysis further reveals that small clear vesicles participate in exocytosis. In addition, the released ATP activates P2X7 receptors in satellite cells that enwrap each DRG neuron and triggers the communication between neuronal somata and glial cells. Blocking L-type Ca2+ channels completely eliminates the neuron–glia communication. We further show that activation of P2X7 receptors can lead to the release of tumor necrosis factor-α (TNFα) from satellite cells. TNFα in turn potentiates the P2X3 receptor-mediated responses and increases the excitability of DRG neurons. This study provides strong evidence that somata of DRG neurons actively release transmitters and play a crucial role in bidirectional communication between neurons and surrounding satellite glial cells. These results also suggest that, contrary to the conventional view, neuronal somata have a significant role in cell–cell signaling. PMID:17525149

Yki/YAP, Sd/TEAD and Hth/MEIS Control Tissue Specification in the Drosophila Eye Disc Epithelium

PubMed Central

Pignoni, Francesca

2011-01-01

During animal development, accurate control of tissue specification and growth are critical to generate organisms of reproducible shape and size. The eye-antennal disc epithelium of Drosophila is a powerful model system to identify the signaling pathway and transcription factors that mediate and coordinate these processes. We show here that the Yorkie (Yki) pathway plays a major role in tissue specification within the developing fly eye disc epithelium at a time when organ primordia and regional identity domains are specified. RNAi-mediated inactivation of Yki, or its partner Scalloped (Sd), or increased activity of the upstream negative regulators of Yki cause a dramatic reorganization of the eye disc fate map leading to specification of the entire disc epithelium into retina. On the contrary, constitutive expression of Yki suppresses eye formation in a Sd-dependent fashion. We also show that knockdown of the transcription factor Homothorax (Hth), known to partner Yki in some developmental contexts, also induces an ectopic retina domain, that Yki and Scalloped regulate Hth expression, and that the gain-of-function activity of Yki is partially dependent on Hth. Our results support a critical role for Yki- and its partners Sd and Hth - in shaping the fate map of the eye epithelium independently of its universal role as a regulator of proliferation and survival. PMID:21811580

An Examination of Gender Role Identity, Sexual Self-Esteem, Sexual Coercion and Sexual Victimization in a University Sample

ERIC Educational Resources Information Center

Kelly, Theresa C.; Erickson, Chris D.

2007-01-01

The relationship between gender role identity, sexual self-esteem and sexual coercion was examined through a questionnaire. Participants were 84 undergraduate students from a university in Washington, DC. Contrary to what has been found in the literature, there were weak relationships between sexual coercion and masculinity, and sexual coercion…

Peer Effects in the Workplace: Evidence from Random Groupings in Professional Golf Tournaments

PubMed Central

Guryan, Jonathan; Kroft, Kory; Notowidigdo, Matthew J.

2010-01-01

This paper uses random assignment in professional golf tournaments to test for peer effects in the workplace. We find no evidence that playing partners’ ability affects performance, contrary to recent evidence on peer effects in the workplace from laboratory experiments, grocery scanners, and soft-fruit pickers. In our preferred specification we can rule out peer effects larger than 0.043 strokes for a one stroke increase in playing partners’ ability. Our results complement existing studies on workplace peer effects and are useful in explaining how social effects vary across labor markets, across individuals, and with the form of incentives faced. PMID:20454555

Complementing Gender Analysis Methods.

PubMed

Kumar, Anant

2016-01-01

The existing gender analysis frameworks start with a premise that men and women are equal and should be treated equally. These frameworks give emphasis on equal distribution of resources between men and women and believe that this will bring equality which is not always true. Despite equal distribution of resources, women tend to suffer and experience discrimination in many areas of their lives such as the power to control resources within social relationships, and the need for emotional security and reproductive rights within interpersonal relationships. These frameworks believe that patriarchy as an institution plays an important role in women's oppression, exploitation, and it is a barrier in their empowerment and rights. Thus, some think that by ensuring equal distribution of resources and empowering women economically, institutions like patriarchy can be challenged. These frameworks are based on proposed equality principle which puts men and women in competing roles. Thus, the real equality will never be achieved. Contrary to the existing gender analysis frameworks, the Complementing Gender Analysis framework proposed by the author provides a new approach toward gender analysis which not only recognizes the role of economic empowerment and equal distribution of resources but suggests to incorporate the concept and role of social capital, equity, and doing gender in gender analysis which is based on perceived equity principle, putting men and women in complementing roles that may lead to equality. In this article the author reviews the mainstream gender theories in development from the viewpoint of the complementary roles of gender. This alternative view is argued based on existing literature and an anecdote of observations made by the author. While criticizing the equality theory, the author offers equity theory in resolving the gender conflict by using the concept of social and psychological capital.

The choice of the speed of an airship

NASA Technical Reports Server (NTRS)

Munk, Max M

1922-01-01

The favorable speed of an airship is chiefly determined by the condition of the consumption of the least amount of fuel per unit of traveled distance, although other conditions come into play. The resulting rules depend on the character of the wind and on the variability of the efficiency of the engine propeller units. This investigation resulted in the following rules. 1) Always keep the absolute course and steer at such an angle with reference to it as to neutralize the side wind. 2) In a strong contrary wind, take a speed one and one half times the velocity of the wind. 3) As a general rule, take the velocity of the wind and the velocity of the course component of the wind. Add them together if the wind has a contrary component, but subtract them from each other if the wind has a favorable component.

Wandering tales: evolutionary origins of mental time travel and language

PubMed Central

Corballis, Michael C.

2013-01-01

A central component of mind wandering is mental time travel, the calling to mind of remembered past events and of imagined future ones. Mental time travel may also be critical to the evolution of language, which enables us to communicate about the non-present, sharing memories, plans, and ideas. Mental time travel is indexed in humans by hippocampal activity, and studies also suggest that the hippocampus in rats is active when the animals replay or pre play activity in a spatial environment, such as a maze. Mental time travel may have ancient origins, contrary to the view that it is unique to humans. Since mental time travel is also thought to underlie language, these findings suggest that language evolved gradually from pre-existing cognitive capacities, contrary to the view of Chomsky and others that language and symbolic thought emerged abruptly, in a single step, within the past 100,000 years. PMID:23908641

Feeling and thinking of others: affective and cognitive empathy and emotion comprehension in prosocial/hostile preschoolers.

PubMed

Belacchi, Carmen; Farina, Eleonora

2012-01-01

This study aims at investigating the affective and cognitive components of empathy in relation to both emotion comprehension and prosocial/hostile behaviors in preschoolers. A total of 219 children (54% boys; aged between 3 and 6: mean age 4.10) and 20 teachers (two for each class: group A and group B) took part in this research. Pupils' empathy and hostile/prosocial roles were assessed by teacher reports [Belacchi and Farina, 2010] and children's emotion comprehension by a nonverbal test [Test of Emotion Comprehension: Pons and Harris, 2000; adapted by Albanese and Molina; 2008]. As expected, the results showed a significant influence of gender, with girls being more empathic than boys, according to all of the teachers' perception. Contrary to our expectations, no systematic age influence emerged. Regarding the relations of children's emotion comprehension with both empathy measures and their prosocial/hostile attitudes, we have found: (1) a low significant relation with the total empathy measure, according to all the teachers, but with the cognitive empathy only according to teachers B; (2) a robust negative relationship of both affective and cognitive empathy with Hostile roles and with Outsider role, contrary to a positive correlation of only affective empathy with Prosocial roles. No relationships emerged between empathy measures and Victim role. © 2012 Wiley Periodicals, Inc.

Structural and catalytic effects of an invariant purine substitution in the hammerhead ribozyme: implications for the mechanism of acid–base catalysis

PubMed Central

Schultz, Eric P.; Vasquez, Ernesto E.; Scott, William G.

2014-01-01

The hammerhead ribozyme catalyzes RNA cleavage via acid–base catalysis. Whether it does so by general acid–base catalysis, in which the RNA itself donates and abstracts protons in the transition state, as is typically assumed, or by specific acid–base catalysis, in which the RNA plays a structural role and proton transfer is mediated by active-site water molecules, is unknown. Previous biochemical and crystallographic experiments implicate an invariant purine in the active site, G12, as the general base. However, G12 may play a structural role consistent with specific base catalysis. To better understand the role of G12 in the mechanism of hammerhead catalysis, a 2.2 Å resolution crystal structure of a hammerhead ribozyme from Schistosoma mansoni with a purine substituted for G12 in the active site of the ribozyme was obtained. Comparison of this structure (PDB entry 3zd4), in which A12 is substituted for G, with three previously determined structures that now serve as important experimental controls, allows the identification of structural perturbations that are owing to the purine substitution itself. Kinetic measurements for G12 purine-substituted schistosomal hammerheads confirm a previously observed dependence of rate on the pK a of the substituted purine; in both cases inosine, which is similar to G in pK a and hydrogen-bonding properties, is unexpectedly inactive. Structural comparisons indicate that this may primarily be owing to the lack of the exocyclic 2-amino group in the G12A and G12I substitutions and its structural effect upon both the nucleotide base and phosphate of A9. The latter involves the perturbation of a previously identified and well characterized metal ion-binding site known to be catalytically important in both minimal and full-length hammerhead ribozyme sequences. The results permit it to be suggested that G12 plays an important role in stabilizing the active-site structure. This result, although not inconsistent with the potential role of G12 as a general base, indicates that an alternative hammerhead cleavage mechanism involving specific base catalysis may instead explain the observed rate dependence upon purine substitutions at G12. The crystallographic results, contrary to previous assumptions, therefore cannot be interpreted to favor the general base catalysis mecahnism over the specific base catalysis mechanism. Instead, both of these mutually exclusive mechanistic alternatives must be considered in light of the current structural and biochemical data. PMID:25195740

Structural and catalytic effects of an invariant purine substitution in the hammerhead ribozyme: implications for the mechanism of acid-base catalysis.

PubMed

Schultz, Eric P; Vasquez, Ernesto E; Scott, William G

2014-09-01

The hammerhead ribozyme catalyzes RNA cleavage via acid-base catalysis. Whether it does so by general acid-base catalysis, in which the RNA itself donates and abstracts protons in the transition state, as is typically assumed, or by specific acid-base catalysis, in which the RNA plays a structural role and proton transfer is mediated by active-site water molecules, is unknown. Previous biochemical and crystallographic experiments implicate an invariant purine in the active site, G12, as the general base. However, G12 may play a structural role consistent with specific base catalysis. To better understand the role of G12 in the mechanism of hammerhead catalysis, a 2.2 Å resolution crystal structure of a hammerhead ribozyme from Schistosoma mansoni with a purine substituted for G12 in the active site of the ribozyme was obtained. Comparison of this structure (PDB entry 3zd4), in which A12 is substituted for G, with three previously determined structures that now serve as important experimental controls, allows the identification of structural perturbations that are owing to the purine substitution itself. Kinetic measurements for G12 purine-substituted schistosomal hammerheads confirm a previously observed dependence of rate on the pK(a) of the substituted purine; in both cases inosine, which is similar to G in pK(a) and hydrogen-bonding properties, is unexpectedly inactive. Structural comparisons indicate that this may primarily be owing to the lack of the exocyclic 2-amino group in the G12A and G12I substitutions and its structural effect upon both the nucleotide base and phosphate of A9. The latter involves the perturbation of a previously identified and well characterized metal ion-binding site known to be catalytically important in both minimal and full-length hammerhead ribozyme sequences. The results permit it to be suggested that G12 plays an important role in stabilizing the active-site structure. This result, although not inconsistent with the potential role of G12 as a general base, indicates that an alternative hammerhead cleavage mechanism involving specific base catalysis may instead explain the observed rate dependence upon purine substitutions at G12. The crystallographic results, contrary to previous assumptions, therefore cannot be interpreted to favor the general base catalysis mecahnism over the specific base catalysis mechanism. Instead, both of these mutually exclusive mechanistic alternatives must be considered in light of the current structural and biochemical data.

Current Research In The Institut D'optique - Orsay

NASA Astrophysics Data System (ADS)

Marechal, A.

1985-01-01

I - FUNDAMENTAL PROBLEMS A. ASPECT : Non locality in wave mechanics. The Einstein-Bohr dispute and the optical test of Bell's inequalities. A. Einstein and N. Bohr had a discussion about the role of probabilities in microphysics; as is well known the location and momentum of particles cannot be known precisely but only through probabilistic expressions. Einstein thought that complementary variables (hidden variables) are unknown at the present time and that the knowledge of those variables would suppress the actual uncertainty "God does not play random games". On the contrary, Bohr advocated the fundamental role of probabilities. During the sixties J. Bell established inequalities supporting the Einstein point of view. These inequalities are in contradiction with the predictions of quantum mechanics in some very rare situations. A.Aspect designed and realised an optical experiment where the correlation of polarisation of photons emitted by a single atom was measured with a very good signal to noise ratio. Moreover the orientation of the polarisation analyser was changed during the time of flight of photons. The experimental result is in full agreement with the point of view of N. Bohr : the uncertainty on the movement of particles is a fundamental component of the laws of nature and Bell's inequalities do not hold.

Activated Monocytes Enhance Platelet-Driven Contraction of Blood Clots via Tissue Factor Expression.

PubMed

Peshkova, Alina D; Le Minh, Giang; Tutwiler, Valerie; Andrianova, Izabella A; Weisel, John W; Litvinov, Rustem I

2017-07-11

Platelet-driven reduction in blood clot volume (clot contraction or retraction) has been implicated to play a role in hemostasis and thrombosis. Although these processes are often linked with inflammation, the role of inflammatory cells in contraction of blood clots and thrombi has not been investigated. The aim of this work was to study the influence of activated monocytes on clot contraction. The effects of monocytes were evaluated using a quantitative optical tracking methodology to follow volume changes in a blood clot formed in vitro. When a physiologically relevant number of isolated human monocytes pre-activated with phorbol-12-myristate-13-acetate (PMA) were added back into whole blood, the extent and rate of clot contraction were increased compared to addition of non-activated cells. Inhibition of tissue factor expression or its inactivation on the surface of PMA-treated monocytes reduced the extent and rate of clot contraction back to control levels with non-activated monocytes. On the contrary, addition of tissue factor enhanced clot contraction, mimicking the effects of tissue factor expressed on the activated monocytes. These data suggest that the inflammatory cells through their expression of tissue factor can directly affect hemostasis and thrombosis by modulating the size and density of intra- and extravascular clots and thrombi.

Mutations in the netrin-1 gene cause congenital mirror movements.

PubMed

Méneret, Aurélie; Franz, Elizabeth A; Trouillard, Oriane; Oliver, Thomas C; Zagar, Yvrick; Robertson, Stephen P; Welniarz, Quentin; Gardner, R J MacKinlay; Gallea, Cécile; Srour, Myriam; Depienne, Christel; Jasoni, Christine L; Dubacq, Caroline; Riant, Florence; Lamy, Jean-Charles; Morel, Marie-Pierre; Guérois, Raphael; Andreani, Jessica; Fouquet, Coralie; Doulazmi, Mohamed; Vidailhet, Marie; Rouleau, Guy A; Brice, Alexis; Chédotal, Alain; Dusart, Isabelle; Roze, Emmanuel; Markie, David

2017-11-01

Netrin-1 is a secreted protein that was first identified 20 years ago as an axon guidance molecule that regulates midline crossing in the CNS. It plays critical roles in various tissues throughout development and is implicated in tumorigenesis and inflammation in adulthood. Despite extensive studies, no inherited human disease has been directly associated with mutations in NTN1, the gene coding for netrin-1. Here, we have identified 3 mutations in exon 7 of NTN1 in 2 unrelated families and 1 sporadic case with isolated congenital mirror movements (CMM), a disorder characterized by involuntary movements of one hand that mirror intentional movements of the opposite hand. Given the diverse roles of netrin-1, the absence of manifestations other than CMM in NTN1 mutation carriers was unexpected. Using multimodal approaches, we discovered that the anatomy of the corticospinal tract (CST) is abnormal in patients with NTN1-mutant CMM. When expressed in HEK293 or stable HeLa cells, the 3 mutated netrin-1 proteins were almost exclusively detected in the intracellular compartment, contrary to WT netrin-1, which is detected in both intracellular and extracellular compartments. Since netrin-1 is a diffusible extracellular cue, the pathophysiology likely involves its loss of function and subsequent disruption of axon guidance, resulting in abnormal decussation of the CST.

Role of afferent input and mechanical load for size regulation of rat soleus muscle

NASA Astrophysics Data System (ADS)

Kawano, Fuminori; Matsuka, Yoshikazu; Oke, Yoshihiko; Higo, Yoko; Terada, Masahiro; Umemoto, Shiori; Kawabe, Naoko; Wang, Xiao Dong; Shinoda, Yo; Lan, Yong Bo; Fukuda, Hiroyuki; Ohmi, Shinobu; Ohira, Yoshinobu

2005-08-01

Effects of deafferentation on the phosphorylation of ribosomal protein S6 (S6), 27 kDa heat shock protein (HSP27) and extracellular signal-regulated kinase (ERK) 1/2 were studied in rat soleus muscle. Adult male Wistar rats were randomly separated into the pre- and post- experimental control, functionally overloaded (FO), sham-operated, deafferentated (DA), FO+DA, and hindlimb-unloaded (U) groups. The distal tendons of left plantaris and gastrocnemius muscles were transected in the FO rats. The left dorsal roots of the spinal cord at the L4-5 segmental levels were transected in the DA rats. The rats in U were tail-suspended. The sampling of the soleus muscle was performed 2 weeks after the treatments shown above. The cytoplasmic fraction of the soleus muscle homogenate was used for the quantitative analyses of the phosphorylation levels of S6, HSP27, and ERK 1/2. The phosphorylation levels of these proteins were up-regulated by FO. On the contrary, the phosphorylation of all of these proteins was down-regulated by U and DA. Further, the FO-related increase of the protein phosphorylation was inhibited by additional treatment with DA. These results indicated that the afferent feedback plays crucial roles in the intramuscular regulation of the soleus muscle mass.

Nonshivering thermogenesis in king penguin chicks. I. Role of skeletal muscle.

PubMed

Duchamp, C; Barré, H; Rouanet, J L; Lanni, A; Cohen-Adad, F; Berne, G; Brebion, P

1991-12-01

In cold-acclimatized (CA) king penguin chicks exhibiting nonshivering thermogenesis (NST), protein content and cytochrome oxidase (CO) activity of tissue homogenates were measured together with protein content, CO, and respiration rates of isolated mitochondria from skeletal muscle (gastrocnemius and pectoralis) and liver. The comparison was made with chicks reared at thermoneutrality (TN) for at least 3 wk. In CA chicks showing a NST despite the lack of brown adipose tissue, an increase in thermogenic capacity was observed in skeletal muscle in which the oxidative capacity rose (+28% and +50% in gastrocnemius and pectoralis muscles, respectively), whereas no change occurred in the liver. Oxidative capacity of skeletal muscle increased together with the development of mitochondrial inner membrane plus cristae in muscles of CA chicks contrary to their TN littermates (+30 to +50%). Subsarcolemmal mitochondria of CA chicks had a higher protein content (+65% in gastrocnemius muscle) and higher oxidative capacities than in controls. The lower respiratory control ratio of these mitochondria might result from a low ADP phosphorylation rate. No change occurred in the intermyofibrillar fraction nor in liver mitochondria. These findings together with earlier results obtained in cold-acclimated ducklings indicate the marked and suited adaptation of skeletal muscle and in particular of subsarcolemmal mitochondria allowing them to play a role in NST.

Social capital, collective action, and communal grazing lands in Uganda

PubMed Central

Call, Maia; Jagger, Pamela

2018-01-01

Recent scholars have found that collective action can be harnessed to sustainably manage common property, contrary to longstanding hypotheses that without effective external regulation community members will exploit communal resources. Researchers have also found that social capital, in addition to biophysical conditions and community attributes, is an important element of successful collective action. However, few studies exploring this topic have specifically examined communal grazing land, which is a critical component of rural livelihoods in many parts of the developing world. To address this gap, we explore the role that collective action plays in maintaining communal grazing lands through bridging, bonding, and linking social capital. In cases where the community does have communal grazing lands, we also explore the role of social capital in determining the condition of the land and the inclusiveness of access. Our analyses draw upon a community-level dataset composed of Uganda RePEAT survey data linked with high resolution gridded socio-environmental data. We observe that strong community bonds are associated with higher odds of successful collective action. However, increased links to external market forces may decrease the odds of successful collective action. These findings provide additional evidence for the complex relationship between social capital, collective action, and common property natural resource management. PMID:29377036

TCF3, a novel positive regulator of osteogenesis, plays a crucial role in miR-17 modulating the diverse effect of canonical Wnt signaling in different microenvironments

PubMed Central

Liu, W; Liu, Y; Guo, T; Hu, C; Luo, H; Zhang, L; Shi, S; Cai, T; Ding, Y; Jin, Y

2013-01-01

Wnt signaling pathways are a highly conserved pathway, which plays an important role from the embryonic development to bone formation. The effect of Wnt pathway on osteogenesis relies on their cellular environment and the expression of target genes. However, the molecular mechanism of that remains unclear. On the basis of the preliminary results, we observed the contrary effect of canonical Wnt signaling on osteogenic differentiation of periodontal ligament stem cells (PDLSCs) in the different culture environment. Furthermore, we found that the expression level of miR-17 was also varied with the change in the culture environment. Therefore, we hypothesized that miR-17 and canonical Wnt signaling may have potential interactions, particularly the inner regulation relationship in different microenvironments. In this paper, we observed that canonical Wnt signaling promoted osteogenesis of PDLSCs in the fully culture medium, while inhibited it in the osteogenic differentiation medium. Interestingly, alteration in the expression level of endogenous miR-17 could partially reverse the different effect of canonical Wnt signaling. Furthermore, the role of miR-17 was because of its target gene TCF3 (transcription factor 3), a key transcription factor of canonical Wnt pathway. Overexpression of TCF3 attenuated the effect of miR-17 on modulating canonical Wnt signaling. Finally, we elucidated that TCF3 enhanced osteogenesis both in vitro and in vivo. In brief, the different level of miR-17 was the main cause of the different effect of canonical Wnt signaling, and TCF3 was the crucial node of miR-17–canonial Wnt signaling regulation loop. This understanding of microRNAs regulating signaling pathways in different microenvironments may pave the way for fine-tuning the process of osteogenesis in bone-related disorders. PMID:23492770

TCF3, a novel positive regulator of osteogenesis, plays a crucial role in miR-17 modulating the diverse effect of canonical Wnt signaling in different microenvironments.

PubMed

Liu, W; Liu, Y; Guo, T; Hu, C; Luo, H; Zhang, L; Shi, S; Cai, T; Ding, Y; Jin, Y

2013-03-14

Wnt signaling pathways are a highly conserved pathway, which plays an important role from the embryonic development to bone formation. The effect of Wnt pathway on osteogenesis relies on their cellular environment and the expression of target genes. However, the molecular mechanism of that remains unclear. On the basis of the preliminary results, we observed the contrary effect of canonical Wnt signaling on osteogenic differentiation of periodontal ligament stem cells (PDLSCs) in the different culture environment. Furthermore, we found that the expression level of miR-17 was also varied with the change in the culture environment. Therefore, we hypothesized that miR-17 and canonical Wnt signaling may have potential interactions, particularly the inner regulation relationship in different microenvironments. In this paper, we observed that canonical Wnt signaling promoted osteogenesis of PDLSCs in the fully culture medium, while inhibited it in the osteogenic differentiation medium. Interestingly, alteration in the expression level of endogenous miR-17 could partially reverse the different effect of canonical Wnt signaling. Furthermore, the role of miR-17 was because of its target gene TCF3 (transcription factor 3), a key transcription factor of canonical Wnt pathway. Overexpression of TCF3 attenuated the effect of miR-17 on modulating canonical Wnt signaling. Finally, we elucidated that TCF3 enhanced osteogenesis both in vitro and in vivo. In brief, the different level of miR-17 was the main cause of the different effect of canonical Wnt signaling, and TCF3 was the crucial node of miR-17-canonial Wnt signaling regulation loop. This understanding of microRNAs regulating signaling pathways in different microenvironments may pave the way for fine-tuning the process of osteogenesis in bone-related disorders.

Mast cells play no role in the pathogenesis of postoperative ileus induced by intestinal manipulation.

PubMed

Gomez-Pinilla, Pedro J; Farro, Giovanna; Di Giovangiulio, Martina; Stakenborg, Nathalie; Némethova, Andrea; de Vries, Annick; Liston, Adrian; Feyerabend, Thorsten B; Rodewald, Hans-Reimer; Rodewald, Hans-Reimwer; Boeckxstaens, Guy E; Matteoli, Gianluca

2014-01-01

Intestinal manipulation (IM) during abdominal surgery results in intestinal inflammation leading to hypomotility or ileus. Mast cell activation is thought to play a crucial role in the pathophysiology of postoperative ileus (POI). However, this conclusion was mainly drawn using mast cell-deficient mouse models with abnormal Kit signaling. These mice also lack interstitial cells of Cajal (ICC) resulting in aberrant gastrointestinal motility even prior to surgery, compromising their use as model to study POI. To avoid these experimental weaknesses we took advantage of a newly developed knock-in mouse model, Cpa3(Cre/+) , devoid of mast cells but with intact Kit signaling. The role of mast cells in the development of POI and intestinal inflammation was evaluated assessing gastrointestinal transit and muscularis externa inflammation after IM in two strains of mice lacking mast cells, i.e. Kit(W-sh/W-sh) and Cpa3(Cre/+) mice, and by use of the mast cell stabilizer cromolyn. Kit(W-sh/W-sh) mice lack ICC networks and already revealed significantly delayed gastrointestinal transit even before surgery. IM did not further delay intestinal transit, but induced infiltration of myeloperoxidase positive cells, expression of inflammatory cytokines and recruitment of monocytes and neutrophils into the muscularis externa. On the contrary, Cpa3(Cre/+) mice have a normal network of ICC and normal gastrointestinal. Surprisingly, IM in Cpa3(Cre/+) mice caused delay in gut motility and intestinal inflammation as in wild type littermates mice (Cpa3(+/+) ). Furthermore, treatment with the mast cell inhibitor cromolyn resulted in an inhibition of mast cells without preventing POI. Here, we confirm that IM induced mast cell degranulation. However, our data demonstrate that mast cells are not required for the pathogenesis of POI in mice. Although there might be species differences between mouse and human, our results argue against mast cell inhibitors as a therapeutic approach to shorten POI.

Mast Cells Play No Role in the Pathogenesis of Postoperative Ileus Induced by Intestinal Manipulation

PubMed Central

Gomez-Pinilla, Pedro J.; Farro, Giovanna; Di Giovangiulio, Martina; Stakenborg, Nathalie; Némethova, Andrea; de Vries, Annick; Liston, Adrian; Feyerabend, Thorsten B.; Rodewald, Hans-Reimwer; Boeckxstaens, Guy E.; Matteoli, Gianluca

2014-01-01

Introduction Intestinal manipulation (IM) during abdominal surgery results in intestinal inflammation leading to hypomotility or ileus. Mast cell activation is thought to play a crucial role in the pathophysiology of postoperative ileus (POI). However, this conclusion was mainly drawn using mast cell-deficient mouse models with abnormal Kit signaling. These mice also lack interstitial cells of Cajal (ICC) resulting in aberrant gastrointestinal motility even prior to surgery, compromising their use as model to study POI. To avoid these experimental weaknesses we took advantage of a newly developed knock-in mouse model, Cpa3Cre/+, devoid of mast cells but with intact Kit signaling. Design The role of mast cells in the development of POI and intestinal inflammation was evaluated assessing gastrointestinal transit and muscularis externa inflammation after IM in two strains of mice lacking mast cells, i.e. KitW-sh/W-sh and Cpa3Cre/+ mice, and by use of the mast cell stabilizer cromolyn. Results KitW-sh/W-sh mice lack ICC networks and already revealed significantly delayed gastrointestinal transit even before surgery. IM did not further delay intestinal transit, but induced infiltration of myeloperoxidase positive cells, expression of inflammatory cytokines and recruitment of monocytes and neutrophils into the muscularis externa. On the contrary, Cpa3Cre/+ mice have a normal network of ICC and normal gastrointestinal. Surprisingly, IM in Cpa3Cre/+ mice caused delay in gut motility and intestinal inflammation as in wild type littermates mice (Cpa3+/+). Furthermore, treatment with the mast cell inhibitor cromolyn resulted in an inhibition of mast cells without preventing POI. Conclusions Here, we confirm that IM induced mast cell degranulation. However, our data demonstrate that mast cells are not required for the pathogenesis of POI in mice. Although there might be species differences between mouse and human, our results argue against mast cell inhibitors as a therapeutic approach to shorten POI. PMID:24416383

Population differences in host use by a seed-beetle: local adaptation, phenotypic plasticity and maternal effects.

PubMed

Amarillo-Suárez, Angela R; Fox, Charles W

2006-11-01

For insects that develop inside discrete hosts, both host size and host quality constrain offspring growth, influencing the evolution of body size and life history traits. Using a two-generation common garden experiment, we quantified the contribution of maternal and rearing hosts to differences in growth and life history traits between populations of the seed-feeding beetle Stator limbatus that use a large-seeded host, Acacia greggii, and a small-seeded host, Pseudosamanea guachapele. Populations differed genetically for all traits when beetles were raised in a common garden. Contrary to expectations from the local adaptation hypothesis, beetles from all populations were larger, developed faster and had higher survivorship when reared on seeds of A. greggii (the larger host), irrespective of their native host. We observed two host plant-mediated maternal effects: offspring matured sooner, regardless of their rearing host, when their mothers were reared on P. guachapele (this was not caused by an effect of rearing host on egg size), and females laid larger eggs on P. guachapele. This is the first study to document plasticity by S. limbatus in response to P. guachapele, suggesting that plasticity is an ancestral trait in S. limbatus that likely plays an important role in diet expansion. Although differences between populations in growth and life history traits are likely adaptations to their host plants, host-associated maternal effects, partly mediated by maternal egg size plasticity, influence growth and life history traits and likely play an important role in the evolution of the breadth of S. limbatus' diet. More generally, phenotypic plasticity mediates the fitness consequences of using novel hosts, likely facilitating colonization of new hosts, but also buffering herbivores from selection post-colonization. Plasticity in response to novel versus normal hosts varied among our study populations such that disentangling the historical role of plasticity in mediating diet evolution requires the consideration of evolutionary history.

Young adults, social networks, and addiction recovery: post treatment changes in social ties and their role as a mediator of 12-step participation.

PubMed

Kelly, John F; Stout, Robert L; Greene, M Claire; Slaymaker, Valerie

2014-01-01

Social factors play a key role in addiction recovery. Research with adults indicates individuals with substance use disorder (SUD) benefit from mutual-help organizations (MHOs), such as Alcoholics Anonymous, via their ability to facilitate adaptive network changes. Given the lower prevalence of sobriety-conducive, and sobriety-supportive, social contexts in the general population during the life-stage of young adulthood, however, 12-step MHOs may play an even more crucial recovery-supportive social role for young adults, but have not been investigated. Greater knowledge could enhance understanding of recovery-related change and inform young adults' continuing care recommendations. Emerging adults (N = 302; 18-24 yrs; 26% female; 95% White) enrolled in a study of residential treatment effectiveness were assessed at intake, 1, 3, 6, and 12 months on 12-step attendance, peer network variables ("high [relapse] risk" and "low [relapse] risk" friends), and treatment outcomes (Percent Days Abstinent; Percent Days Heavy Drinking). Hierarchical linear models tested for change in social risk over time and lagged mediational analyses tested whether 12-step attendance conferred recovery benefits via change in social risk. High-risk friends were common at treatment entry, but decreased during follow-up; low-risk friends increased. Contrary to predictions, while substantial recovery-supportive friend network changes were observed, this was unrelated to 12-step participation and, thus, not found to mediate its positive influence on outcome. Young adult 12-step participation confers recovery benefit; yet, while encouraging social network change, 12-step MHOs may be less able to provide social network change directly for young adults, perhaps because similar-aged peers are less common in MHOs. Findings highlight the importance of both social networks and 12-step MHOs and raise further questions as to how young adults benefit from 12-step MHOs.

Sentence processing and verbal working memory in a white-matter-disconnection patient.

PubMed

Meyer, Lars; Cunitz, Katrin; Obleser, Jonas; Friederici, Angela D

2014-08-01

The Arcuate Fasciculus/Superior Longitudinal Fasciculus (AF/SLF) is the white-matter bundle that connects posterior superior temporal and inferior frontal cortex. Its causal functional role in sentence processing and verbal working memory is currently under debate. While impairments of sentence processing and verbal working memory often co-occur in patients suffering from AF/SLF damage, it is unclear whether these impairments result from shared white-matter damage to the verbal-working-memory network. The present study sought to specify the behavioral consequences of focal AF/SLF damage for sentence processing and verbal working memory, which were assessed in a single patient suffering from a cleft-like lesion spanning the deep left superior temporal gyrus, sparing most surrounding gray matter. While tractography suggests that the ventral fronto-temporal white-matter bundle is intact in this patient, the AF/SLF was not visible to tractography. In line with the hypothesis that the AF/SLF is causally involved in sentence processing, the patient׳s performance was selectively impaired on sentences that jointly involve both complex word orders and long word-storage intervals. However, the patient was unimpaired on sentences that only involved long word-storage intervals without involving complex word orders. On the contrary, the patient performed generally worse than a control group across standard verbal-working-memory tests. We conclude that the AF/SLF not only plays a causal role in sentence processing, linking regions of the left dorsal inferior frontal gyrus to the temporo-parietal region, but moreover plays a crucial role in verbal working memory, linking regions of the left ventral inferior frontal gyrus to the left temporo-parietal region. Together, the specific sentence-processing impairment and the more general verbal-working-memory impairment may imply that the AF/SLF subserves both sentence processing and verbal working memory, possibly pointing to the AF and SLF respectively supporting each. Copyright © 2014 Elsevier Ltd. All rights reserved.

Can role-play with interactive simulations enhance climate change knowledge, affect and intent to act?

NASA Astrophysics Data System (ADS)

Rooney-varga, J. N.; Sterman, J.; Fracassi, E. P.; Franck, T.; Kapmeier, F.; Kurker, V.; Jones, A.; Rath, K.

2017-12-01

The strong scientific consensus about the reality and risks of anthropogenic climate change stands in stark contrast to widespread confusion and complacency among the public. Many efforts to close that gap, grounded in the information deficit model of risk communication, provide scientific information on climate change through reports and presentations. However, research shows that showing people research does not work: the gap between scientific and public understanding of climate change remains wide. Tools that are rigorously grounded in the science and motivate action on climate change are urgently needed. Here we assess the impact of one such tool, an interactive, role-play simulation, World Climate. Participants take the roles of delegates to the UN climate negotiations and are challenged to create an agreement limiting warming to no more than 2°C. The C-ROADS climate simulation model then provides participants with immediate feedback about the expected impacts of their decisions. Participants use C-ROADS to explore the climate system and use the results to refine their negotiating positions, learning about climate change while experiencing the social dynamics of negotiations and decision-making. Pre- and post-survey results from 21 sessions in eight nations showed significant gains in participants' climate change knowledge, affective engagement, intent to take action, and desire to learn. Contrary to the deficit model, gains in participants' desire to learn more and intention to act were associated with gains in affective engagement, particularly feelings of urgency and hope, but not climate knowledge. Gains were just as strong among participants who oppose government regulation, suggesting the simulation's potential to reach across political divides. Results indicate that simulations like World Climate offer a climate change communication tool that enables people to learn and feel for themselves, which together have the potential to motivate action informed by science.

Unveiling the Role of the Magnetic Field at the Smallest Scales of Star Formation

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

Hull, Charles L. H.; Mocz, Philip; Burkhart, Blakesley

We report Atacama Large Millimeter/submillimeter Array (ALMA) observations of polarized dust emission from the protostellar source Ser-emb 8 at a linear resolution of 140 au. Assuming models of dust-grain alignment hold, the observed polarization pattern gives a projected view of the magnetic field structure in this source. Contrary to expectations based on models of strongly magnetized star formation, the magnetic field in Ser-emb 8 does not exhibit an hourglass morphology. Combining the new ALMA data with previous observational studies, we can connect magnetic field structure from protostellar core (∼80,000 au) to disk (∼100 au) scales. We compare our observations withmore » four magnetohydrodynamic gravo-turbulence simulations made with the AREPO code that have initial conditions ranging from super-Alfvénic (weakly magnetized) to sub-Alfvénic (strongly magnetized). These simulations achieve the spatial dynamic range necessary to resolve the collapse of protostars from the parsec scale of star-forming clouds down to the ∼100 au scale probed by ALMA. Only in the very strongly magnetized simulation do we see both the preservation of the field direction from cloud to disk scales and an hourglass-shaped field at <1000 au scales. We conduct an analysis of the relative orientation of the magnetic field and the density structure in both the Ser-emb 8 ALMA observations and the synthetic observations of the four AREPO simulations. We conclude that the Ser-emb 8 data are most similar to the weakly magnetized simulations, which exhibit random alignment, in contrast to the strongly magnetized simulation, where the magnetic field plays a role in shaping the density structure in the source. In the weak-field case, it is turbulence—not the magnetic field—that shapes the material that forms the protostar, highlighting the dominant role that turbulence can play across many orders of magnitude in spatial scale.« less

FMRI-adaptation to highly-rendered color photographs of animals and manipulable artifacts during a classification task.

PubMed

Chouinard, Philippe A; Goodale, Melvyn A

2012-02-01

We used fMRI to identify brain areas that adapted to either animals or manipulable artifacts while participants classified highly-rendered color photographs into subcategories. Several key brain areas adapted more strongly to one class of objects compared to the other. Namely, we observed stronger adaptation for animals in the lingual gyrus bilaterally, which are known to analyze the color of objects, and in the right frontal operculum and in the anterior insular cortex bilaterally, which are known to process emotional content. In contrast, the left anterior intraparietal sulcus, which is important for configuring the hand to match the three-dimensional structure of objects during grasping, adapted more strongly to manipulable artifacts. Contrary to what a previous study has found using gray-scale photographs, we did not replicate categorical-specific adaptation in the lateral fusiform gyrus for animals and categorical-specific adaptation in the medial fusiform gyrus for manipulable artifacts. Both categories of objects adapted strongly in the fusiform gyrus without any clear preference in location along its medial-lateral axis. We think that this is because the fusiform gyrus has an important role to play in color processing and hence its responsiveness to color stimuli could be very different than its responsiveness to gray-scale photographs. Nevertheless, on the basis of what we found, we propose that the recognition and subsequent classification of animals may depend primarily on perceptual properties, such as their color, and on their emotional content whereas other factors, such as their function, may play a greater role for classifying manipulable artifacts. Copyright © 2011 Elsevier Inc. All rights reserved.

Do recruitment patterns of young men who have sex with men (YMSM) recruited through respondent-driven sampling (RDS) violate assumptions?

PubMed

Phillips, Gregory; Kuhns, Lisa M; Garofalo, Rob; Mustanski, Brian

2014-12-01

To generate unbiased estimates for data collected using respondent-driven sampling (RDS), a number of assumptions need to be met: individuals recruit randomly from their social network and people can accurately report their eligible network size. However, research has shown that these assumptions are often violated. This study used baseline data from Crew 450, a longitudinal study of young men who have sex with men in Chicago who were recruited via a modified form of RDS and its network substudy, in which a subset of 175 participants reported details on the composition and characteristics of their social network at either 1 or 2 years postbaseline. Nearly two-thirds of participants reported giving coupons to at least one alter (64%), and 56.3% believed their alter(s) used the coupons. Frequency of communication, closeness and type of relationship played a major role in determining coupon distribution. Participants whose alters used coupons were significantly less likely to describe the strength of their relationship as 'not at all close' (OR=0.08; 95% CI 0.02 to 0.36) compared with 'very close' and to communicate weekly (OR=0.20; 95% CI 0.08 to 0.49) or 1-6 times in the past 6 months (OR=0.18; 95% CI 0.06 to 0.59). Contrary to RDS assumptions, we found that relationship characteristics played a significant role when individuals decided to whom they would give coupons. 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.

Central command: control of cardiac sympathetic and vagal efferent nerve activity and the arterial baroreflex during spontaneous motor behaviour in animals.

PubMed

Matsukawa, Kanji

2012-01-01

Feedforward control by higher brain centres (termed central command) plays a role in the autonomic regulation of the cardiovascular system during exercise. Over the past 20 years, workers in our laboratory have used the precollicular-premammillary decerebrate animal model to identify the neural circuitry involved in the CNS control of cardiac autonomic outflow and arterial baroreflex function. Contrary to the traditional idea that vagal withdrawal at the onset of exercise causes the increase in heart rate, central command did not decrease cardiac vagal efferent nerve activity but did allow cardiac sympathetic efferent nerve activity to produce cardiac acceleration. In addition, central command-evoked inhibition of the aortic baroreceptor-heart rate reflex blunted the baroreflex-mediated bradycardia elicited by aortic nerve stimulation, further increasing the heart rate at the onset of exercise. Spontaneous motor activity and associated cardiovascular responses disappeared in animals decerebrated at the midcollicular level. These findings indicate that the brain region including the caudal diencephalon and extending to the rostral mesencephalon may play a role in generating central command. Bicuculline microinjected into the midbrain ventral tegmental area of decerebrate rats produced a long-lasting repetitive activation of renal sympathetic nerve activity that was synchronized with the motor nerve discharge. When lidocaine was microinjected into the ventral tegmental area, the spontaneous motor activity and associated cardiovascular responses ceased. From these findings, we conclude that cerebral cortical outputs trigger activation of neural circuits within the caudal brain, including the ventral tegmental area, which causes central command to augment cardiac sympathetic outflow at the onset of exercise in decerebrate animal models.

Effects of spatial subsidies and habitat structure on the foraging ecology and size of geckos

USGS Publications Warehouse

Briggs, Amy A.; Young, Hillary S.; McCauley, Douglas J.; Hathaway, Stacie A.; Dirzo, Rodolfo; Fisher, Robert N.

2012-01-01

While it is well established that ecosystem subsidies—the addition of energy, nutrients, or materials across ecosystem boundaries—can affect consumer abundance, there is less information available on how subsidy levels may affect consumer diet, body condition, trophic position, and resource partitioning among consumer species. There is also little information on whether changes in vegetation structure commonly associated with spatial variation in subsidies may play an important role in driving consumer responses to subsidies. To address these knowledge gaps, we studied changes in abundance, diet, trophic position, size, and body condition of two congeneric gecko species (Lepidodactylus spp.) that coexist in palm dominated and native (hereafter dicot dominated) forests across the Central Pacific. These forests differ trongly both in the amount of marine subsidies that they receive from seabird guano and carcasses, and in the physical structure of the habitat. Contrary to other studies, we found that subsidy level had no impact on the abundance of either gecko species; it also did not have any apparent effects on resource partitioning between species. However, it did affect body size, dietary composition, and trophic position of both species. Geckos in subsidized, dicot forests were larger, had higher body condition and more diverse diets, and occupied a much higher trophic position than geckos found in palm dominated, low subsidy level forests. Both direct variation in subsidy levels and associated changes in habitat structure appear to play a role in driving these responses. These results suggest that variation in subsidy levels may drive important behavioral responses in predators, even when their numerical response is limited. Strong changes in trophic position of consumers also suggest that subsidies may drive increasingly complex food webs, with longer overall food chain length.

Extreme Inverted Trophic Pyramid of Reef Sharks Supported by Spawning Groupers.

PubMed

Mourier, Johann; Maynard, Jeffrey; Parravicini, Valeriano; Ballesta, Laurent; Clua, Eric; Domeier, Michael L; Planes, Serge

2016-08-08

The extent of the global human footprint [1] limits our understanding of what is natural in the marine environment. Remote, near-pristine areas provide some baseline expectations for biomass [2, 3] and suggest that predators dominate, producing an inverted biomass pyramid. The southern pass of Fakarava atoll-a biosphere reserve in French Polynesia-hosts an average of 600 reef sharks, two to three times the biomass per hectare documented for any other reef shark aggregations [4]. This huge biomass of predators makes the trophic pyramid inverted. Bioenergetics models indicate that the sharks require ∼90 tons of fish per year, whereas the total fish production in the pass is ∼17 tons per year. Energetic theory shows that such trophic structure is maintained through subsidies [5-9], and empirical evidence suggests that sharks must engage in wide-ranging foraging excursions to meet energy needs [9, 10]. We used underwater surveys and acoustic telemetry to assess shark residency in the pass and feeding behavior and used bioenergetics models to understand energy flow. Contrary to previous findings, our results highlight that sharks may overcome low local energy availability by feeding on fish spawning aggregations, which concentrate energy from other local trophic pyramids. Fish spawning aggregations are known to be targeted by sharks, but they were previously believed to play a minor role representing occasional opportunistic supplements. This research demonstrates that fish spawning aggregations can play a significant role in the maintenance of local inverted pyramids in pristine marine areas. Conservation of fish spawning aggregations can help conserve shark populations, especially if combined with shark fishing bans. Copyright © 2016 Elsevier Ltd. All rights reserved.

Implications of extreme sexual size dimorphism for thermoregulation in a freshwater turtle.

PubMed

Bulté, Grégory; Blouin-Demers, Gabriel

2010-02-01

Sexual size dimorphism (SSD) is a common phenomenon in animals. In many species females are substantially larger than males. Because body size plays a central role in modulating the body temperature (T (b)) of ectotherms, intersexual differences in body size may lead to important intersexual differences in thermoregulation. In addition, because SSD is realized by differences in growth rate and because growth rate is strongly temperature dependent in ectotherms, a conflict between male reproductive behaviour and thermoregulation may affect the expression of SSD. In this study, we investigated the thermal implications of SSD in a reptile exhibiting spectacular female-biased SSD: the northern map turtle (Graptemys geographica). Over three seasons, we collected >150,000 measurements of T (b) in free-ranging adult and juvenile northern map turtles using surgically implanted miniature temperature loggers. Northern map turtles exhibited seasonal patterns of thermoregulation typical of reptiles in northern latitudes, but we found that large adult females experienced a lower daily maximum T (b) and a narrower daily range of T (b) than adult males and small juvenile females. In addition, despite more time spent basking, large adult females were not able to thermoregulate as accurately as small turtles. Our findings strongly suggest that body size limits the ability to thermoregulate accurately in large females. By comparing thermoregulatory patterns between adult males and juvenile females of similar body size, we found no evidence that male reproductive behaviours are an impediment to thermoregulation. We also quantified the thermal significance of basking behaviour. We found, contrary to previous findings, that aerial basking allows northern map turtles to raise their T (b) substantially above water temperature, indicating that basking behaviour likely plays an important role in thermoregulation.

[Myotonic dystrophies: clinical presentation, pathogenesis, diagnostics and therapy].

PubMed

Finsterer, Josef; Rudnik-Schöneborn, S

2015-01-01

The autosomal-dominant myotonic dystrophies dystrophia myotonica type-1 (DM1, Curschmann-Steinert disease) and dystrophia myotonica type-2 (DM2, proximal myotonic myopathy (PROMM)), are, contrary to the non-dystrophic myotonias, progressive multisystem disorders. DM1 and DM2 are the most frequent of the muscular dystrophies. In both diseases the skeletal muscle is the most severely affected organ (weakness, wasting, myotonia, myalgia). Additionally, they manifest in the eye, heart, brain, endocrine glands, gastrointestinal tract, skin, skeleton, and peripheral nerves. Phenotypes of DM1 may be classified as congenital, juvenile, classical, or late onset. DM2 is a disorder of the middle or older age and usually has a milder course compared to DM1. DM1 is due to a CTG-repeat expansion > 50 repeats in the non-coding 3' UTR of the DMPK-gene. DM2 is caused by a CCTG-repeat expansion to 75 - 11 000 repeats in intron-1 of the CNBP/ZNF9 gene. Mutant pre-mRNAs of both genes aggregate within the nucleus (nuclear foci), which sequester RNA-binding proteins and result in an abnormal protein expression via alternative splicing in downstream effector genes (toxic RNA diseases). Other mechanisms seem to play an additional pathogenetic role. Clinical severity of DM1 increases from generation to generation (anticipation). The higher the repeat expansion the more severe the DM1 phenotype. In DM2 severity of symptoms and age at onset do not correlate with the expansion size. Contrary to DM2, there is a congenital form and anticipation in DM1. © Georg Thieme Verlag KG Stuttgart · New York.

Nutrition in adult and childhood cancer: role of carcinogens and anti-carcinogens.

PubMed

Mosby, Terezie T; Cosgrove, Maeve; Sarkardei, Samiramis; Platt, Karl L; Kaina, Bernd

2012-10-01

There is no doubt that diet is one of the main modifiable risk factors for many degenerative diseases, including cancer. More than 30% of adult cancers can be prevented or delayed by diet, being physically active and having a healthy body weight. Plant-based foods, including fruit, vegetables, and whole grains, a favorable omega-6/omega-3 polyunsaturated fatty acids ratio, and fish consumption have a protective effect against cancer. On the contrary, a low intake of fruit and vegetables, high intake of red and processed meat, high intake of sodium, alcohol consumption, a diet rich in refined carbohydrates, and a high intake of total fat may increase risk of cancer. Furthermore, calorie restriction and having a body/mass index on the lower end of the normal range can significantly decrease or delay the onset of cancers. Most studies were performed on adults and thus the role of diet in childhood cancer is less well-understood. In the past, diet was not considered to play any role in its etiology in children. However, nowadays there is a growing body of evidence that prolonged and frequent breastfeeding, the maternal diet during pregnancy and vitamin intake during pregnancy, may impart benefit for reduced cancer risk in children. Usually, decades of healthy dietary habits are needed to see significant difference in cancer risk. Therefore, diet choices and diet preparation starting early in life deserve more attention. Here we review data focusing on which dietary factors, including food-borne carcinogens, affect the onset of cancers in adults and stress out the potential role of diet in childhood cancer prevention.

The role of interfacial water layer in atmospherically relevant charge separation

NASA Astrophysics Data System (ADS)

Bhattacharyya, Indrani

Charge separation at interfaces is important in various atmospheric processes, such as thunderstorms, lightning, and sand storms. It also plays a key role in several industrial processes, including ink-jet printing and electrostatic separation. Surprisingly, little is known about the underlying physics of these charging phenomena. Since thin films of water are ubiquitous, they may play a role in these charge separation processes. This talk will focus on the experimental investigation of the role of a water adlayer in interfacial charging, with relevance to meteorologically important phenomena, such as atmospheric charging due to wave actions on oceans and sand storms. An ocean wave generates thousands of bubbles, which upon bursting produce numerous large jet droplets and small film droplets that are charged. In the 1960s, Blanchard showed that the jet droplets are positively charged. However, the charge on the film droplets was not known. We designed an experiment to exclusively measure the charge on film droplets generated by bubble bursting on pure water and aqueous salt solution surfaces. We measured their charge to be negative and proposed a model where a slight excess of hydroxide ions in the interfacial water layer is responsible for generating these negatively charged droplets. The findings from this research led to a better understanding of the ionic disposition at the air-water interface. Sand particles in a wind-blown sand layer, or 'saltation' layer, become charged due to collisions, so much so, that it can cause lightning. Silica, being hydrophilic, is coated with a water layer even under low-humidity conditions. To investigate the importance of this water adlayer in charging the silica surfaces, we performed experiments to measure the charge on silica surfaces due to contact and collision processes. In case of contact charging, the maximum charge separation occurred at an optimum relative humidity. On the contrary, in collisional charging process, no humidity effect was observed. We proposed an ion transfer mechanism in case of contact charging. However, an electron transfer mechanism explained the collisional charging process. The effects of temperature, surface roughness, and chemical nature of surface were also studied for both contact and collisional charging processes.

Approximate Bayesian Computation Reveals the Crucial Role of Oceanic Islands for the Assembly of Continental Biodiversity.

PubMed

Patiño, Jairo; Carine, Mark; Mardulyn, Patrick; Devos, Nicolas; Mateo, Rubén G; González-Mancebo, Juana M; Shaw, A Jonathan; Vanderpoorten, Alain

2015-07-01

The perceived low levels of genetic diversity, poor interspecific competitive and defensive ability, and loss of dispersal capacities of insular lineages have driven the view that oceanic islands are evolutionary dead ends. Focusing on the Atlantic bryophyte flora distributed across the archipelagos of the Azores, Madeira, the Canary Islands, Western Europe, and northwestern Africa, we used an integrative approach with species distribution modeling and population genetic analyses based on approximate Bayesian computation to determine whether this view applies to organisms with inherent high dispersal capacities. Genetic diversity was found to be higher in island than in continental populations, contributing to mounting evidence that, contrary to theoretical expectations, island populations are not necessarily genetically depauperate. Patterns of genetic variation among island and continental populations consistently fitted those simulated under a scenario of de novo foundation of continental populations from insular ancestors better than those expected if islands would represent a sink or a refugium of continental biodiversity. We, suggest that the northeastern Atlantic archipelagos have played a key role as a stepping stone for transoceanic migrants. Our results challenge the traditional notion that oceanic islands are the end of the colonization road and illustrate the significant role of oceanic islands as reservoirs of novel biodiversity for the assembly of continental floras. © The Author(s) 2015. Published by Oxford University Press, on behalf of the Society of Systematic Biologists. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

System level mechanisms of adaptation, learning, memory formation and evolvability: the role of chaperone and other networks.

PubMed

Gyurko, David M; Soti, Csaba; Stetak, Attila; Csermely, Peter

2014-05-01

During the last decade, network approaches became a powerful tool to describe protein structure and dynamics. Here, we describe first the protein structure networks of molecular chaperones, then characterize chaperone containing sub-networks of interactomes called as chaperone-networks or chaperomes. We review the role of molecular chaperones in short-term adaptation of cellular networks in response to stress, and in long-term adaptation discussing their putative functions in the regulation of evolvability. We provide a general overview of possible network mechanisms of adaptation, learning and memory formation. We propose that changes of network rigidity play a key role in learning and memory formation processes. Flexible network topology provides ' learning-competent' state. Here, networks may have much less modular boundaries than locally rigid, highly modular networks, where the learnt information has already been consolidated in a memory formation process. Since modular boundaries are efficient filters of information, in the 'learning-competent' state information filtering may be much smaller, than after memory formation. This mechanism restricts high information transfer to the 'learning competent' state. After memory formation, modular boundary-induced segregation and information filtering protect the stored information. The flexible networks of young organisms are generally in a 'learning competent' state. On the contrary, locally rigid networks of old organisms have lost their 'learning competent' state, but store and protect their learnt information efficiently. We anticipate that the above mechanism may operate at the level of both protein-protein interaction and neuronal networks.

Role of matrix metalloproteinases in radicular cysts and periapical granulomas.

PubMed

D'addazio, G; Artese, L; Piccirilli, M; Perfetti, G

2014-01-01

The aim of the present study was to evaluate the expression and distribution of different classes of matrix metalloproteinases (MMPs) in radicular cysts and periapical granulomas. Twenty consecutive specimens of radicular cysts and 20 of periapical granulomas were selected. Expression of MMP-2, -9, -8, -13, -3 was immunohistochemically evaluated. The intensity of expression of the MMPs was evaluated using a semi-quantitative analysis: low = +; intermediate = ++; high = +++. Positive expression of MMPs was present with different distribution. MMP-9 expressed differently in the lesions. Indeed, in periapical granulomas low expression was found in endothelial cells and fibroblasts, whilst high intensities were only detected in inflammatory cells. On the contrary, in radicular cysts the high intensities were mainly present in keratinocytes and fibroblasts. MMP-8 was mainly expressed in inflammatory cells of periapical granulomas. MMP-2 and -3 presented a low intensity of expression in both groups. MMP-13 showed a variable pattern of distribution in the different cell types of the two different lesions. The present investigation supports the role of MMPs in the inflammatory process leading to the development of radicular cysts and periapical granulomas. The results of the present study suggested that the increased enlargement of radicular cysts, compared to periapical granulomas, might be related to a higher expression of MMP-9. On the other hands, the higher intensity of expression of MMP-8 in periapical granulomas could be related to an active inflammatory process. MMP-8 could play an important role in the inflammation processes during the development of periapical lesions.

Study of the structural role of gallium and aluminum in 45S5 bioactive glasses by molecular dynamics simulations.

PubMed

Malavasi, Gianluca; Pedone, Alfonso; Menziani, Maria Cristina

2013-04-18

The structural properties of phosphosilicate glasses based on the 45S5 Bioglass doped with gallium and aluminum (46.2 SiO2·24.3Na2O·26.9CaO·2.6P2O5·1.0X2O3, X = Ga or Al) are investigated by means of classical molecular dynamics simulations. Structural features of the two compositions are compared with those of the original 45S5 Bioglass in order to relate them to the different known bioactivities of these materials. Differences in the coordination environments of Ga and Al, network connectivity, and ion aggregation reveal a microscopic model of these glasses which supports the interpretation of the experimental data and provides new insight into the different biological behaviors of Ga- and Al-containing phosphosilicate glasses. Although Ga is found predominantly in a 4-fold coordination environment, small amounts of 5- and 6-fold coordinated atoms have been detected depending on the interatomic potential model employed. This suggests its possible intermediate role in phosphosilicate glasses. On the contrary, Al plays a network former role and leads to glasses with a more polymerized structure. Interestingly, the results show an increased propensity for aggregation of the Ca(2+) and PO4(3-) ions in the Al-containing phosphosilicate glasses with respect to the Ga-containing ones. This leads to insoluble calcium-phosphate-rich regions not detected in the bioactive glasses.

Aging, Gender Role, and Friendship.

ERIC Educational Resources Information Center

Hess, Beth B.

1982-01-01

Contrary to the bonding mystique, there is increasing evidence that women's lives are not lacking in friends nor men's so well-endowed. Women's well-developed interpersonal skills are an asset when events such as spouse's death or retirement require the reconstruction of social networks. (Author/SK)

The Role of Interpersonal Comfort in Mentoring Relationships

ERIC Educational Resources Information Center

Allen, Tammy D.; Day, Rachel; Lentz, Elizabeth

2005-01-01

This research examined interpersonal comfort as a potential mediating mechanism in mentoring relationships. Results indicated that interpersonal comfort mediated the relationship between gender similarity and protege reports of career and psychosocial mentoring. Contrary to prediction, interpersonal comfort did not mediate relationships involving…

Active depinning of bacterial droplets: The collective surfing of Bacillus subtilis

PubMed Central

Hennes, Marc; Tailleur, Julien; Charron, Gaëlle

2017-01-01

How systems are endowed with migration capacity is a fascinating question with implications ranging from the design of novel active systems to the control of microbial populations. Bacteria, which can be found in a variety of environments, have developed among the richest set of locomotion mechanisms both at the microscopic and collective levels. Here, we uncover, experimentally, a mode of collective bacterial motility in humid environment through the depinning of bacterial droplets. Although capillary forces are notoriously enormous at the bacterial scale, even capable of pinning water droplets of millimetric size on inclined surfaces, we show that bacteria are able to harness a variety of mechanisms to unpin contact lines, hence inducing a collective slipping of the colony across the surface. Contrary to flagella-dependent migration modes like swarming, we show that this much faster “colony surfing” still occurs in mutant strains of Bacillus subtilis lacking flagella. The active unpinning seen in our experiments relies on a variety of microscopic mechanisms, which could each play an important role in the migration of microorganisms in humid environment. PMID:28536199

Exciplexes versus Loose Ion Pairs: How Does the Driving Force Impact the Initial Product Ratio of Photoinduced Charge Separation Reactions?

PubMed Central

2014-01-01

Many donor–acceptor systems can undergo a photoinduced charge separation reaction, yielding loose ion pairs (LIPs). LIPs can be formed either directly via (distant) electron transfer (ET) or indirectly via the dissociation of an initially formed exciplex or tight ion pair. Establishing the prevalence of one of the reaction pathways is challenging because differentiating initially formed exciplexes from LIPs is difficult due to similar spectroscopic footprints. Hence, no comprehensive reaction model has been established for moderately polar solvents. Here, we employ an approach based on the time-resolved magnetic field effect (MFE) of the delayed exciplex luminescence to distinguish the two reaction channels. We focus on the effects of the driving force of ET and the solvent permittivity. We show that, surprisingly, the exciplex channel is significant even for an exergonic ET system with a free energy of ET of −0.58 eV and for the most polar solutions studied (butyronitrile). Our findings demonstrate that exciplexes play a crucial role even in polar solvents and at moderate driving forces, contrary to what is usually assumed. PMID:25243054

Vitiligo susceptibility and catalase gene (CAT) polymorphisms in sicilian population.

PubMed

Caputo, Valentina; Niceta, Marcello; Fiorella, Santi; La Vecchia, Marco; Bastonini, Emanuela; Bongiorno, Maria R; Pistone, Giuseppe

2017-02-15

Catalase gene (CAT) polymorphisms were analyzed as responsible for the deficiency of catalase enzyme activity and concomitant accumulation of excessive hydrogen peroxide in Vitiligo patients. Catalase is a well known oxidative stress regulator that could play an important role in the pathogenesis of Vitiligo. This study was conducted to evaluate three CAT gene polymorphisms (-89A/T, 389C/T, 419C/T) and their association with Vitiligo susceptibility in Sicilian population. 60 out of 73 Sicilian patients with Vitiligo were enrolled and submitted to CAT gene analysis. Contrary to the Northern part of Europe but likewise to the Mediterranean area, the frequency of the CAT genotypes in Sicily is equally distributed. Out of all CAT genotypes, only CAT -89 T/T frequency was found to be significantly higher amongst Vitiligo patients than controls. Despite the involvement of the CAT enzyme in the pathogenesis of Vitiligo, the biological significance of CAT gene polymorphisms is still controversial. With the only exception for CAT variant -89A/T, the other studied CAT gene polymorphisms (389C/T and 419C/T) might not to be associated with Vitiligo in Sicilian population.

A novel angle computation and calibration algorithm of bio-inspired sky-light polarization navigation sensor.

PubMed

Xian, Zhiwen; Hu, Xiaoping; Lian, Junxiang; Zhang, Lilian; Cao, Juliang; Wang, Yujie; Ma, Tao

2014-09-15

Navigation plays a vital role in our daily life. As traditional and commonly used navigation technologies, Inertial Navigation System (INS) and Global Navigation Satellite System (GNSS) can provide accurate location information, but suffer from the accumulative error of inertial sensors and cannot be used in a satellite denied environment. The remarkable navigation ability of animals shows that the pattern of the polarization sky can be used for navigation. A bio-inspired POLarization Navigation Sensor (POLNS) is constructed to detect the polarization of skylight. Contrary to the previous approach, we utilize all the outputs of POLNS to compute input polarization angle, based on Least Squares, which provides optimal angle estimation. In addition, a new sensor calibration algorithm is presented, in which the installation angle errors and sensor biases are taken into consideration. Derivation and implementation of our calibration algorithm are discussed in detail. To evaluate the performance of our algorithms, simulation and real data test are done to compare our algorithms with several exiting algorithms. Comparison results indicate that our algorithms are superior to the others and are more feasible and effective in practice.

Aggression, segregation and stability in a dominance hierarchy

PubMed Central

Ang, Tzo Zen; Manica, Andrea

2010-01-01

Central to our understanding of social group formation and maintenance is the question of how within-group conflict resolution is achieved in the face of asymmetrical competition over resources and reproduction. A crucial yet implicit assumption of many conflict resolution models dealing with reproductive skew is that subordinates have perfect knowledge of the extent of conflict between themselves and their dominants, enabling behavioural responses on an individual rather than evolutionary scale. However, a mechanism enabling subordinates to accurately assess their relative conflict levels has yet to be empirically demonstrated. Here, we show in the angelfish Centropyge bicolor that the rate of overt mild aggression from dominants to subordinates acts as a signal of increasing rank conflict. The clarity of this signal can be reduced by spatial segregation, causing subordinates to be less able to respond appropriately by regulation of their foraging rates. A reduced signal ultimately leads to a less well-defined dominance hierarchy and destabilization of the social group. Our study suggests that, contrary to previous suggestions, dominant aggression rates play a crucial role as an accurate information signal required for the evolutionary stability of skew models. PMID:20053647

Ellagic acid promotes A{beta}42 fibrillization and inhibits A{beta}42-induced neurotoxicity

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

Feng, Ying; Tsinghua University School of Medicine, Haidian District, Beijing 100084; Yang, Shi-gao

Smaller, soluble oligomers of {beta}-amyloid (A{beta}) play a critical role in the pathogenesis of Alzheimer's disease (AD). Selective inhibition of A{beta} oligomer formation provides an optimum target for AD therapy. Some polyphenols have potent anti-amyloidogenic activities and protect against A{beta} neurotoxicity. Here, we tested the effects of ellagic acid (EA), a polyphenolic compound, on A{beta}42 aggregation and neurotoxicity in vitro. EA promoted A{beta} fibril formation and significant oligomer loss, contrary to previous results that polyphenols inhibited A{beta} aggregation. The results of transmission electron microscopy (TEM) and Western blot displayed more fibrils in A{beta}42 samples co-incubated with EA in earlier phasesmore » of aggregation. Consistent with the hypothesis that plaque formation may represent a protective mechanism in which the body sequesters toxic A{beta} aggregates to render them harmless, our MTT results showed that EA could significantly reduce A{beta}42-induced neurotoxicity toward SH-SY5Y cells. Taken together, our results suggest that EA, an active ingredient in many fruits and nuts, may have therapeutic potential in AD.« less

Electronic structure of lanthanide scandates

NASA Astrophysics Data System (ADS)

Mizzi, Christopher A.; Koirala, Pratik; Marks, Laurence D.

2018-02-01

X-ray photoelectron spectroscopy, ultraviolet photoelectron spectroscopy, and density functional theory calculations were used to study the electronic structure of three lanthanide scandates: GdSc O3,TbSc O3 , and DySc O3 . X-ray photoelectron spectra simulated from first-principles calculations using a combination of on-site hybrid and GGA +U methods were found to be in good agreement with experimental x-ray photoelectron spectra. The hybrid method was used to model the ground state electronic structure and the GGA +U method accounted for the shift of valence state energies due to photoelectron emission via a Slater-Janak transition state approach. From these results, the lanthanide scandate valence bands were determined to be composed of Ln 4 f ,O 2 p , and Sc 3 d states, in agreement with previous work. However, contrary to previous work the minority Ln 4 f states were found to be located closer to, and in some cases at, the valence band maximum. This suggests that minority Ln 4 f electrons may play a larger role in lanthanide scandate properties than previously thought.

Roughness topographical effects on mean momentum and stress budgets in developed turbulent channel flows

NASA Astrophysics Data System (ADS)

Aghaei Jouybari, Mostafa; Yuan, Junlin

2017-11-01

Direct numerical simulations of turbulent channel flows are carried out over two surfaces: a synthesized sand-grain surface and a realistic turbine roughness that is characterized by more prominent large-scale surface features. To separate the effects of wall-normal variation of the roughness area fraction from the (true) variation of flow statistics, the governing equations are area-averaged using intrinsic averaging, contrary to the usually practice based on the total area (i.e., superficial averaging). Additional terms appear in the mean-momentum equation resulted from the wall-normal variation of the solid fraction and play a role in the near-wall balance. Results from surfaces with a step solidity function (e.g., cubes) will also be discussed. Compared to the sand grains, the turbine surface generates stronger form-induced fluctuations, despite weaker dispersive shear stress. This is associated with more significant form-induced productions (comparable to shear production) in Reynolds stress budgets, weaker pressure work, and, consequently, more anisotropic redistribution of turbulent kinetic energy in the roughness sublayer, which potentially leads to different turbulent responses between the two surfaces in non-equilibrium flows.

The neural representation of objects formed through the spatiotemporal integration of visual transients

PubMed Central

Erlikhman, Gennady; Gurariy, Gennadiy; Mruczek, Ryan E.B.; Caplovitz, Gideon P.

2016-01-01

Oftentimes, objects are only partially and transiently visible as parts of them become occluded during observer or object motion. The visual system can integrate such object fragments across space and time into perceptual wholes or spatiotemporal objects. This integrative and dynamic process may involve both ventral and dorsal visual processing pathways, along which shape and spatial representations are thought to arise. We measured fMRI BOLD response to spatiotemporal objects and used multi-voxel pattern analysis (MVPA) to decode shape information across 20 topographic regions of visual cortex. Object identity could be decoded throughout visual cortex, including intermediate (V3A, V3B, hV4, LO1-2,) and dorsal (TO1-2, and IPS0-1) visual areas. Shape-specific information, therefore, may not be limited to early and ventral visual areas, particularly when it is dynamic and must be integrated. Contrary to the classic view that the representation of objects is the purview of the ventral stream, intermediate and dorsal areas may play a distinct and critical role in the construction of object representations across space and time. PMID:27033688

Children's feedback preferences in response to an experimentally manipulated peer evaluation outcome: the role of depressive symptoms.

PubMed

Reijntjes, Albert; Dekovic, Maja; Vermande, Marjolijn; Telch, Michael J

2007-06-01

The present study examined the linkage between pre-adolescent children's depressive symptoms and their preferences for receiving positive vs. negative feedback subsequent to being faced with an experimentally manipulated peer evaluation outcome in real time. Participants (n = 142) ages 10 to 13, played a computer contest based on the television show Survivor and were randomized to either a peer rejection (i.e., receiving the lowest total 'likeability' score from a group of peer-judges), a peer success (i.e., receiving the highest score), or a control peer evaluation condition. Children's self-reported feedback preferences were then assessed. Results revealed that participants assigned to the negative evaluation outcome, relative to either the success or the control outcome, showed a significantly higher subsequent preference for negatively tuned feedback. Contrary to previous work and predictions derived from self-verification theory, children higher in depressive symptoms were only more likely to prefer negative feedback in response to the negative peer evaluation outcome. These effects for depression were not accounted for by either state mood at baseline or mood change in response to the feedback manipulation.

Choosy Moral Punishers

PubMed Central

Clavien, Christine; Tanner, Colby J.; Clément, Fabrice; Chapuisat, Michel

2012-01-01

The punishment of social misconduct is a powerful mechanism for stabilizing high levels of cooperation among unrelated individuals. It is regularly assumed that humans have a universal disposition to punish social norm violators, which is sometimes labelled “universal structure of human morality” or “pure aversion to social betrayal”. Here we present evidence that, contrary to this hypothesis, the propensity to punish a moral norm violator varies among participants with different career trajectories. In anonymous real-life conditions, future teachers punished a talented but immoral young violinist: they voted against her in an important music competition when they had been informed of her previous blatant misconduct toward fellow violin students. In contrast, future police officers and high school students did not punish. This variation among socio-professional categories indicates that the punishment of norm violators is not entirely explained by an aversion to social betrayal. We suggest that context specificity plays an important role in normative behaviour; people seem inclined to enforce social norms only in situations that are familiar, relevant for their social category, and possibly strategically advantageous. PMID:22720012

Hilbert's sixth problem: between the foundations of geometry and the axiomatization of physics.

PubMed

Corry, Leo

2018-04-28

The sixth of Hilbert's famous 1900 list of 23 problems was a programmatic call for the axiomatization of the physical sciences. It was naturally and organically rooted at the core of Hilbert's conception of what axiomatization is all about. In fact, the axiomatic method which he applied at the turn of the twentieth century in his famous work on the foundations of geometry originated in a preoccupation with foundational questions related with empirical science in general. Indeed, far from a purely formal conception, Hilbert counted geometry among the sciences with strong empirical content, closely related to other branches of physics and deserving a treatment similar to that reserved for the latter. In this treatment, the axiomatization project was meant to play, in his view, a crucial role. Curiously, and contrary to a once-prevalent view, from all the problems in the list, the sixth is the only one that continually engaged Hilbet's efforts over a very long period of time, at least between 1894 and 1932.This article is part of the theme issue 'Hilbert's sixth problem'. © 2018 The Author(s).

Cognitive stimulation of pupils with Down syndrome: A study of inferential talk during book-sharing.

PubMed

Engevik, Liv Inger; Næss, Kari-Anne B; Hagtvet, Bente E

2016-08-01

In the education of pupils with Down syndrome, "simplifying" literal talk and concrete stimulation have typically played a dominant role. This explorative study investigated the extent to which teachers stimulated abstract cognitive functions via inferential talk during book-sharing and how pupils with Down syndrome responded. Dyadic interactions (N=7) were videotaped, transcribed and coded to identify levels of abstraction in teacher utterances and to evaluate the adequacy of pupil responses. One-third of the teachers' utterances contained high levels of abstraction and promoted inferential talk. Six of the seven children predominantly responded in ways which revealed inferential thinking. Dialog excerpts highlighted individual, contextual and interactional factors contributing to variations in the findings. Contrary to previous claims, the children with Down syndrome in the current sample appear able to draw inferences beyond the "here-and-now" with teacher support. This finding highlights the educational relevance and importance of higher-order cognitive stimulation of pupils with intellectual disabilities, to foster independent metacognitive skills. Copyright © 2016 Elsevier Ltd. All rights reserved.

Genistein isoflavone glycoconjugates in sour cherry (Prunus cerasus L.) cultivars.

PubMed

Abrankó, László; Nagy, Ádám; Szilvássy, Blanka; Stefanovits-Bányai, Éva; Hegedűs, Attila

2015-01-01

The isoflavone genistein on the contrary to its well-established health-beneficial effects is not a major component of the Western diet, since soy consumption, considered as the main dietary source of genistein, in these populations is low. Genistein compounds in twelve commercial sour cherry (Prunus cerasus L.) cultivars grown in Hungary were studied. High performance liquid chromatography coupled to electrospray ionisation quadrupole/time-of-flight mass spectrometry (HPLC-ESI-qToF-MS) was used for screening and confirmatory analyses. Genistin and genistein were found in 'Pipacs1', 'Kántorjánosi', 'Debreceni bőtermő' and 'Éva', which are native cultivars to Hungary. Genistein content of the latter three were in the range of 0.4-0.6, while in 'Pipacs1' in total 4.4 mg genistein compounds were measured expressed as aglycone equivalents per 100g of fresh fruit flesh. These cultivars may play important role as complementary genistein sources in the Western diet. Especially 'Pipacs 1', may be best utilised in functional food products. Copyright © 2014 Elsevier Ltd. All rights reserved.

Phosphorylation of the IDP KID Modulates Affinity for KIX by Increasing the Lifetime of the Complex.

PubMed

Dahal, Liza; Shammas, Sarah L; Clarke, Jane

2017-12-19

Intrinsically disordered proteins (IDPs) are known to undergo a range of posttranslational modifications, but by what mechanism do such modifications affect the binding of an IDP to its partner protein? We investigate this question using one such IDP, the kinase inducible domain (KID) of the transcription factor CREB, which interacts with the KIX domain of CREB-binding protein upon phosphorylation. As with many other IDPs, KID undergoes coupled folding and binding to form α-helical structure upon interacting with KIX. This single site phosphorylation plays an important role in the control of transcriptional activation in vivo. Here we show that, contrary to expectation, phosphorylation has no effect on association rates-unphosphorylated KID binds just as rapidly as pKID, the phosphorylated form-but rather, acts by increasing the lifetime of the complex. We propose that by controlling the lifetime of the bound complex of pKID:KIX via altering the dissociation rate, phosphorylation can facilitate effective control of transcription regulation. Copyright © 2017 Biophysical Society. Published by Elsevier Inc. All rights reserved.

The Crvenka loess-paleosol sequence (Vojvodina, Northern Serbia)- a record of continuous domination of the Late Pleistocene grasslands

NASA Astrophysics Data System (ADS)

Markovic, Slobodan; Sümegi, Pál; Stevens, Thomas; Obreht, Igor; Chu, Wei; Buggle, Björn; Zech, Michael; Zech, Roland; Hambach, Ulrich; Lehmkuhl, Frank; Zeeden, Christian; Gavrilov, Milivoj; Svircev, Zorica

2016-04-01

In this study we present a comparison of two independent paleo-environmental evidences: novel n-alkane biomarkers and traditional land snails assemblages, associated with widely used proxy records such as the low field magnetic susceptibility, grain size and various isotopic and geochemical indices. These paleo-environmental proxy records provide evidence for the continued predominance of the different grassland vegetation types during the entire Late Pleistocene. The results presented in this study highlight the spatial differences in the environmental conditions during the Late Pleistocene across the European loess belt. Contrary to other European loess provinces characterized by high diversity of the Late Pleistocene environments (ranging from tundra-like to deciduous forest habitats), our investigations indicate a continued dominance of grassland-dominated ecosystems in the southeastern Carpathian Basin. This uninterrupted presence of Late Pleistocene grassland zone in the southeastern part of the Carpathian Basin may have played an important role in the preservation of exceptional biodiversity of the Balkan region, as well as in the migration of anatomically modern humans into Europe.

Hilbert's sixth problem: between the foundations of geometry and the axiomatization of physics

NASA Astrophysics Data System (ADS)

Corry, Leo

2018-04-01

The sixth of Hilbert's famous 1900 list of 23 problems was a programmatic call for the axiomatization of the physical sciences. It was naturally and organically rooted at the core of Hilbert's conception of what axiomatization is all about. In fact, the axiomatic method which he applied at the turn of the twentieth century in his famous work on the foundations of geometry originated in a preoccupation with foundational questions related with empirical science in general. Indeed, far from a purely formal conception, Hilbert counted geometry among the sciences with strong empirical content, closely related to other branches of physics and deserving a treatment similar to that reserved for the latter. In this treatment, the axiomatization project was meant to play, in his view, a crucial role. Curiously, and contrary to a once-prevalent view, from all the problems in the list, the sixth is the only one that continually engaged Hilbet's efforts over a very long period of time, at least between 1894 and 1932. This article is part of the theme issue `Hilbert's sixth problem'.

Studies on the advent of ureotelism. Factors that render the hepatic arginase of the Mexican axolotl able to hydrolyse endogenous arginine

PubMed Central

Palacios, R.; Tarrab, Rebeca; Soberón, G.

1968-01-01

1. A study was undertaken of the conditions that might operate in the synthesis and hydrolysis of arginine by axolotl liver homogenate to test a previous postulate that liver arginase of the non-metamorphosed Mexican axolotl is not able to hydrolyse arginine formed from citrulline and aspartic acid, though it can split exogenous arginine, and also that an enhanced capacity to hydrolyse endogenous arginine plays a major role in the advent of ureotelism observed during the metamorphosis of the axolotl. 2. It was found that the arginase from axolotl liver is very unstable under the conditions followed, contrary to what is observed in rat liver. 3. Axolotl arginase is able to hydrolyse endogenous arginine if preserved. 4. Mn2+ protects the enzyme and renders it able to split endogenous arginine. 5. It is suggested that the metal ion produces a change of conformation of the enzyme that, being stable, is capable of hydrolysing the amino acid, or that the new conformation is appropriate for interaction with the sites of arginine synthesis. PMID:5701670

Effect of Gaussian curvature modulus on the shape of deformed hollow spherical objects.

PubMed

Quilliet, C; Farutin, A; Marmottant, P

2016-06-01

A popular description of soft membranes uses the surface curvature energy introduced by Helfrich, which includes a spontaneous curvature parameter. In this paper we show how the Helfrich formula can also be of interest for a wider class of spherical elastic surfaces, namely with shear elasticity, and likely to model other deformable hollow objects. The key point is that when a stress-free state with spherical symmetry exists before subsequent deformation, its straightforwardly determined curvature ("geometrical spontaneous curvature") differs most of the time from the Helfrich spontaneous curvature parameter that should be considered in order to have the model being correctly used. Using the geometrical curvature in a set of independent parameters unveils the role of the Gaussian curvature modulus, which appears to play on the shape of an elastic surface even though this latter is closed, contrary to what happens for surfaces without spontaneous curvature. In appendices, clues are given to apply this alternative and convenient formulation of the elastic surface model to the particular case of thin spherical shells of isotropic material (TSSIMs).

Spectroscopic studies on the interaction of a water-soluble cationic porphyrin with proteins

NASA Astrophysics Data System (ADS)

Ma, Hong-Min; Chen, Xin; Zhang, Nuo; Han, Yan-Yan; Wu, Dan; Du, Bin; Wei, Qin

2009-04-01

The interaction of a water-soluble cationic porphyrin, meso-tetrakis (4- N, N, N-trimethylanilinium) porphyrin (TMAP), with two proteins, bovine serum albumin (BSA) and human serum albumin (HSA), was studied by UV-vis absorption spectroscopy, fluorescence spectroscopy, fluorescence anisotropy and synchronous fluorescence spectroscopy at neutral aqueous solutions. Free base TMAP bound to proteins as monomers and no aggregation was observed. The binding of TMAP quenched the fluorescence of the protein. On the contrary, the fluorescence of TMAP was enhanced and the fluorescence anisotropy increased due to the binding. The direct static binding mechanism could account for the quenching by TMAP and the binding constants were calculated. TMAP showed a higher quenching efficiency and binding constant of HSA than BSA. The binding of TMAP had no obvious effect on the molecular conformation of the protein. There was only one binding site for TMAP and it was located on the surface of the protein molecule. Electrostatic force played an important role in the binding due to the opposite charges on porphyrin and the proteins.

[Orthopedics and patients under national socialism dictatorship].

PubMed

Thomann, K D; Rauschmann, M

2001-10-01

The 12-year dictatorship of National Socialism represents a decisive event in the history of orthopedics in Germany. Treatment and care was limited to those patients whose prognosis promised their reintegration into the work force. Those orthopedic patients with mental and psychological handicaps no longer came under the care of orthopedists and were potential candidates for annihilation. Despite concerted efforts to the contrary, as can be gleaned from the lists of topics at the annual meetings, the prevailing political circumstances encumbered scientific activities. The almost total isolation from international contacts had a negative effect. Orthopedists were hindered in their work by the law on sterilization, which provided for sterilization in cases of severe physical deformity. Some orthopedists even considered the presence of hip dysplasia to be an indication. The roles played by Georg Hohmann, Hellmut Eckhardt, Lothar Kreuz, and other leading orthopedists are described in detail. It can be regarded as certain that Hohmann and Eckhardt were able to prevent dire consequences for their orthopedic patients and the profession by cautious tactics. The ethnical problems of involvement with National Socialism are thoroughly discussed.

Testing two mechanisms by which rational and irrational beliefs may affect the functionality of inferences.

PubMed

Bond, F W; Dryden, W; Briscoe, R

1999-12-01

This article describes a role playing experiment that examined the sufficiency hypothesis of Rational Emotive Behaviour Therapy (REBT). This proposition states that it is sufficient for rational and irrational beliefs to refer to preferences and musts, respectively, if those beliefs are to affect the functionality of inferences (FI). Consistent with the REBT literature (e.g. Dryden, 1994; Dryden & Ellis, 1988; Palmer, Dryden, Ellis & Yapp, 1995) results from this experiment showed that rational and irrational beliefs, as defined by REBT, do affect FI. Specifically, results showed that people who hold a rational belief form inferences that are significantly more functional than those that are formed by people who hold an irrational belief. Contrary to REBT theory, the sufficiency hypothesis was not supported. Thus, results indicated that it is not sufficient for rational and irrational beliefs to refer to preferences and musts, respectively, if those beliefs are to affect the FI. It appears, then, that preferences and musts are not sufficient mechanisms by which rational and irrational beliefs, respectively, affect the FI. Psychotherapeutic implications of these findings are considered.

Along-strike variation in deformation style inferred from kinematic reconstruction and strain rate analysis: A case study of the Ethiopian Rift

NASA Astrophysics Data System (ADS)

Muluneh, Ameha A.; Cuffaro, Marco; Kidane, Tesfaye

2017-09-01

In this paper we combine kinematic reconstruction and seismic strain rate analysis to understand the along-strike variation in strain accommodation in the Ethiopian Rift (ER) evolution. The reconstruction poles close the southern and central ER at 19 and 15 Myr, respectively whereas there is 34 ± 14 km overlap in the northern ER at 11 Myr. Using Kostrov summation, seismic strain rates of 6.81 ×10-9 yr-1 and 0.06 × 10-9 yr-1 are obtained for the south-central and northern ER, respectively. Comparison of the seismic and geodetic strain rates shows that seismic deformation dominates the south and central ER contrary to the northern ER that deforms aseismically. The results obtained indicate that Nubia/Somalia plate reconstructions together with information on the onset of rifting overestimate the kinematics of the northern ER. We argue that magmatic processes play significant role in accommodating the ∼ 2 Myr opening of the rift. Our findings agree well with previous geophysical and geological studies in the Ethiopian Rift.

N-arachidonoyl L-serine, an endocannabinoid-like brain constituent with vasodilatory properties.

PubMed

Milman, Garry; Maor, Yehoshua; Abu-Lafi, Saleh; Horowitz, Michal; Gallily, Ruth; Batkai, Sandor; Mo, Fong-Ming; Offertaler, Laszlo; Pacher, Pal; Kunos, George; Mechoulam, Raphael

2006-02-14

The endocannabinoid N-arachidonoyl ethanolamine (anandamide), found both in the CNS and in the periphery, plays a role in numerous physiological systems. One might expect that the chemically related N-arachidonoyl-L-serine (ARA-S) could also be formed alongside anandamide. We have now isolated ARA-S from bovine brain and elucidated its structure by comparison with synthetic ARA-S. Contrary to anandamide, ARA-S binds very weakly to cannabinoid CB1 and CB2 or vanilloid TRPV1 (transient receptor potential vanilloid 1) receptors. However, it produces endothelium-dependent vasodilation of rat isolated mesenteric arteries and abdominal aorta and stimulates phosphorylation of p44/42 mitogen-activated protein (MAP) kinase and protein kinase B/Akt in cultured endothelial cells. ARA-S also suppresses LPS-induced formation of TNF-alpha in a murine macrophage cell line and in wild-type mice, as well as in mice deficient in CB1 or CB2 receptors. Many of these effects parallel those reported for abnormal cannabidiol (Abn-CBD), a synthetic agonist of a putative novel cannabinoid-type receptor. Hence, ARA-S may represent an endogenous agonist for this receptor.

The prevalence of deliberate self-harm and its relationships to trauma and dissociation among Iranian young adults.

PubMed

Nobakht, Habib Niyaraq; Dale, Karl Yngvar

2017-01-01

This study aims to investigate the prevalence of deliberate self-harm and its relationships to childhood and recent trauma and different patterns of dissociative features. A total of 100 male and 100 female college students were administered a 58-item questionnaire designed to detect the extent of dissociation, deliberate self-harm, and trauma history. Participants with deliberate self-harm behaviors reported more traumatic experiences and dissociative features than participants without such behaviors. Furthermore, the prevalence of deliberate self-harm (i.e., 40.5%) was similar to previous studies on college student populations. However, and contrary to earlier research, deliberate self-harm was significantly more prevalent among men (48%) than women (33%). The findings support the notion that trauma, pathological dissociation, and depersonalization/derealization play important functional roles in self-harm behaviors. From this perspective, it is feasible to understand individuals who engage in self-harm as either escaping from uncomfortable dissociative states or experiencing an infra-psychological conflict in which one dissociative part of the self is being abusive toward another.

Effects of relationship duration, cohabitation, and marriage on the frequency of intercourse in couples: Findings from German panel data.

PubMed

Schröder, Jette; Schmiedeberg, Claudia

2015-07-01

Research into the changes in the frequency of sexual intercourse is (with few exceptions) limited to cross-sectional analyses of marital duration. We investigate the frequency of intercourse while taking into account relationship duration as well as the duration of cohabitation and marriage, effects of parenthood, and relationship quality. For the analysis we apply fixed effects regression models using data from the German Family Panel (pairfam), a nationwide randomly sampled German panel survey. Our findings imply that the drop in sex frequency occurs early in the relationship, whereas neither cohabitation nor marriage affects the frequency of intercourse to a significant extent. Sex frequency is reduced during pregnancy and as long as the couple has small children, but becomes revived later on. Relationship quality is found to play a role as well. These results are contrary to the honeymoon effect found in earlier research, but indicate that in times of postponed marriage an analogous effect may be at work in the initial period of the relationship. Copyright © 2015 Elsevier Inc. All rights reserved.

Beyond Faces and Expertise: Facelike Holistic Processing of Nonface Objects in the Absence of Expertise.

PubMed

Zhao, Mintao; Bülthoff, Heinrich H; Bülthoff, Isabelle

2016-02-01

Holistic processing-the tendency to perceive objects as indecomposable wholes-has long been viewed as a process specific to faces or objects of expertise. Although current theories differ in what causes holistic processing, they share a fundamental constraint for its generalization: Nonface objects cannot elicit facelike holistic processing in the absence of expertise. Contrary to this prevailing view, here we show that line patterns with salient Gestalt information (i.e., connectedness, closure, and continuity between parts) can be processed as holistically as faces without any training. Moreover, weakening the saliency of Gestalt information in these patterns reduced holistic processing of them, which indicates that Gestalt information plays a crucial role in holistic processing. Therefore, holistic processing can be achieved not only via a top-down route based on expertise, but also via a bottom-up route relying merely on object-based information. The finding that facelike holistic processing can extend beyond the domains of faces and objects of expertise poses a challenge to current dominant theories. © The Author(s) 2015.

Percolation study for the capillary ascent of a liquid through a granular soil

NASA Astrophysics Data System (ADS)

Cárdenas-Barrantes, Manuel Antonio; Muñoz, José Daniel; Araujo, Nuno Machado

2017-06-01

Capillary rise plays a crucial role in the construction of road embankments in flood zones, where hydrophobic compounds are added to the soil to suppress the rising of water and avoid possible damage of the pavement. Water rises through liquid bridges, menisci and trimers, whose width and connectivity depends on the maximal half-length λ of the capillary bridges among grains. Low λs generate a disconnect structure, with small clusters everywhere. On the contrary, for high λ, create a percolating cluster of trimers and enclosed volumes that form a natural path for capillary rise. Hereby, we study the percolation transition of this geometric structure as a function of λ on a granular media of monodisperse spheres in a random close packing. We determine both the percolating threshold λc = (0.049 ± 0.004)R (with R the radius of the granular spheres), and the critical exponent of the correlation length v = 0.830 ± 0.051, suggesting that the percolation transition falls into the universality class of ordinary percolation.

Spectroscopic studies on the interaction of a water-soluble cationic porphyrin with proteins.

PubMed

Ma, Hong-Min; Chen, Xin; Zhang, Nuo; Han, Yan-Yan; Wu, Dan; Du, Bin; Wei, Qin

2009-04-01

The interaction of a water-soluble cationic porphyrin, meso-tetrakis (4-N,N,N-trimethylanilinium) porphyrin (TMAP), with two proteins, bovine serum albumin (BSA) and human serum albumin (HSA), was studied by UV-vis absorption spectroscopy, fluorescence spectroscopy, fluorescence anisotropy and synchronous fluorescence spectroscopy at neutral aqueous solutions. Free base TMAP bound to proteins as monomers and no aggregation was observed. The binding of TMAP quenched the fluorescence of the protein. On the contrary, the fluorescence of TMAP was enhanced and the fluorescence anisotropy increased due to the binding. The direct static binding mechanism could account for the quenching by TMAP and the binding constants were calculated. TMAP showed a higher quenching efficiency and binding constant of HSA than BSA. The binding of TMAP had no obvious effect on the molecular conformation of the protein. There was only one binding site for TMAP and it was located on the surface of the protein molecule. Electrostatic force played an important role in the binding due to the opposite charges on porphyrin and the proteins.

Science Teaching and Argumentation: One-sided versus dialectical argumentation in Chilean middle-school science lessons

NASA Astrophysics Data System (ADS)

Larrain, Antonia; Freire, Paulina; Howe, Christine

2014-04-01

Since the late 1990s, there has been consensus among educational researchers that argumentation should play a central role in science education. Although there has been extensive relevant research, it is not clear enough how oral argumentation spontaneously occurs in science teaching. This is particularly important with regard to the empirical evidence suggesting the effect of discussion of contradictory views on scientific learning. In order to contribute to the research on argumentation in science teaching, we conducted a study that aims to sketch a panoramic view of the uses of oral argumentation in Chilean middle-school science teaching. A total of 153 videotaped science lessons were observed, involving students aged 10-11 and 12-13. Whole-class argumentative discourse was analysed as a function of thematic episodes and teachers' and students' utterances. Results suggest that argumentative discourse in which contradictory points of view are discussed is scarce but when it occurs it does so predominantly within discourse among students. On the contrary, argumentation aimed at justifying points of view is widely used, even more so when students are older.

Shifting the Sun: Solar Spectral Conversion and Extrinsic Sensitization in Natural and Artificial Photosynthesis

PubMed Central

Tyystjärvi, Esa; Méndez‐Ramos, Jorge; Müller, Frank A.; Zhang, Qinyuan

2015-01-01

Solar energy harvesting is largely limited by the spectral sensitivity of the employed energy conversion system, where usually large parts of the solar spectrum do not contribute to the harvesting scheme, and where, of the contributing fraction, the full potential of each photon is not efficiently used in the generation of electrical or chemical energy. Extrinsic sensitization through photoluminescent spectral conversion has been proposed as a route to at least partially overcome this problem. Here, we discuss this approach in the emerging context of photochemical energy harvesting and storage through natural or artificial photosynthesis. Clearly contrary to application in photovoltaic energy conversion, implementation of solar spectral conversion for extrinsic sensitization of a photosynthetic machinery is very straightforward, and—when compared to intrinsic sensitization—less‐strict limitations with regard to quantum coherence are seen. We now argue the ways in which extrinsic sensitization through photoluminescent spectral converters will—and will not—play its role in the area of ultra‐efficient photosynthesis, and also illustrate how such extrinsic sensitization requires dedicated selection of specific conversion schemes and design strategies on system scale. PMID:27774377

Shifting the Sun: Solar Spectral Conversion and Extrinsic Sensitization in Natural and Artificial Photosynthesis.

PubMed

Wondraczek, Lothar; Tyystjärvi, Esa; Méndez-Ramos, Jorge; Müller, Frank A; Zhang, Qinyuan

2015-12-01

Solar energy harvesting is largely limited by the spectral sensitivity of the employed energy conversion system, where usually large parts of the solar spectrum do not contribute to the harvesting scheme, and where, of the contributing fraction, the full potential of each photon is not efficiently used in the generation of electrical or chemical energy. Extrinsic sensitization through photoluminescent spectral conversion has been proposed as a route to at least partially overcome this problem. Here, we discuss this approach in the emerging context of photochemical energy harvesting and storage through natural or artificial photosynthesis. Clearly contrary to application in photovoltaic energy conversion, implementation of solar spectral conversion for extrinsic sensitization of a photosynthetic machinery is very straightforward, and-when compared to intrinsic sensitization-less-strict limitations with regard to quantum coherence are seen. We now argue the ways in which extrinsic sensitization through photoluminescent spectral converters will-and will not-play its role in the area of ultra-efficient photosynthesis, and also illustrate how such extrinsic sensitization requires dedicated selection of specific conversion schemes and design strategies on system scale.

Biological Function of Ribosomal Protein L10 on Cell Behavior in Human Epithelial Ovarian Cancer

PubMed Central

Shi, Jimin; Zhang, Lingyun; Zhou, Daibing; Zhang, Jinguo; Lin, Qunbo; Guan, Wencai; Zhang, Jihong; Ren, Weimin; Xu, Guoxiong

2018-01-01

Ribosomal protein L10 (RPL10) is one of large ribosomal proteins and plays a role in Wilms' tumor and premature ovarian failure. However, the function of RPL10 in human epithelial ovarian cancer (EOC) remains unknown. The purpose of this study was to examine the expression level and function of RPL10 in EOC. RPL10 protein expression was detected by immunohistochemistry and Western blot. The association RPL10 expression with clinical features was analyzed. Loss-of-function and gain-of-function approaches were applied in cellular assays, including cell viability, migration, invasion, and apoptosis. Our study demonstrated for the first time that RPL10 was upregulated in human EOC compared with normal ovarian tissues. Knockdown of RPL10 inhibited cell viability, migration, and invasion, and increased cell apoptosis. On the contrary, upregulation of RPL10 increased cell viability, migration, invasion, and decreased cell apoptosis. Furthermore, miR-143-3p regulated RPL10 expression. Our data indicate that RPL10 is a potential tissue biomarker of patients with EOC and may be a therapeutic target of ovarian cancer. PMID:29556332

Midgut glycosidases activities in monophagous larvae of Apollo butterfly, Parnassius apollo ssp. frankenbergeri.

PubMed

Nakonieczny, Mirosław; Michalczyk, Katarzyna; Kedziorski, Andrzej

2006-10-01

Parnassius apollo (Lepidoptera, Papilionidae) declines on numerous localities all over Europe. Its local subspecies frankenbergeri, inhabiting the Pieniny Mts (southern Poland) and successfully recovered from extinction, is monophagous in larval stage. In natural conditions, it completes development on the orpine Sedum telephium ssp. maximum. Since proper quality and quantity of necessary nutritional compounds of the food plant ensure developmental success, the digestive processes in the insect midgut should reflect adaptation to a specific food source. The paper presents, for the first time, the activity of detected glycolytic enzymes in midgut tissue and liquid gut contents of the L4 and L5 instars of P. apollo larvae. alpha-Amylase plays the main role in utilization of carbohydrates, contrary to cellulase activity. Saccharase seems to be the main disaccharidase, and high activity of beta-glycosidase enables hydrolysis of the plant glycosides. Trehalase activity was unexpectedly low and comparable to those of cellobiase and lactase. alpha-Amylolytic and other glycolytic activities indicate that larvae utilize starch and other carbohydrate compounds as energy sources. Possible use of some plant allelochemicals as energy sources by Apollo larvae is discussed.

Improving oxidative stability of virgin olive oil by addition of microalga Chlorella vulgaris biomass.

PubMed

Alavi, Nasireh; Golmakani, Mohammad-Taghi

2017-07-01

Antioxidant activity of Chlorella ( Chlorella vulgaris ) was evaluated in virgin olive oil (VOO) at different concentrations of 0.5, 1.0, and 1.5% (w/w) under accelerated storage conditions. Antioxidant activity of Chlorella was compared with those of BHT and β-carotene. Chlorella samples significantly retarded the formation of primary, secondary, and total oxidation products in comparison with those of the control. The stability increased as concentrations of Chlorella increased. Samples containing 0.5, 1.0, and 1.5% Chlorella significantly improved VOO stability by 19.99, 28.83, and 33.14%, respectively. Observed effects can be related to the release in the assortment of bioactive compounds from Chlorella algae to the VOO. Among the different antioxidants evaluatedy, BHT exhibited the highest antioxidant activity. On the contrary, β-carotene had no preventive effect against the oxidation of VOO. It also proved incapable of limiting the progress of VOO oxidation and played role as pro-oxidant. In conclusion, Chlorella enhanced VOO oxidative stability. Thus it can be considered as a promising source of natural antioxidants.

Conservation laws in baroclinic inertial-symmetric instabilities

NASA Astrophysics Data System (ADS)

Grisouard, Nicolas; Fox, Morgan B.; Nijjer, Japinder

2017-04-01

Submesoscale oceanic density fronts are structures in geostrophic and hydrostatic balance, but are more prone to instabilities than mesoscale flows. As a consequence, they are believed to play a large role in air-sea exchanges, near-surface turbulence and dissipation of kinetic energy of geostrophically and hydrostatically balanced flows. We will present two-dimensional (x, z) Boussinesq numerical experiments of submesoscale baroclinic fronts on the f-plane. Instabilities of the mixed inertial and symmetric types (the actual name varies across the literature) develop, with the absence of along-front variations prohibiting geostrophic baroclinic instabilities. Two new salient facts emerge. First, contrary to pure inertial and/or pure symmetric instability, the potential energy budget is affected, the mixed instability extracting significant available potential energy from the front and dissipating it locally. Second, in the submesoscale regime, the growth rate of this mixed instability is sufficiently large that significant radiation of near-inertial internal waves occurs. Although energetically small compared to e.g. local dissipation within the front, this process might be a significant source of near-inertial energy in the ocean.

Some challenging points in the identification of defects in floating-zone n-type silicon irradiated with 8 and 15 MeV protons

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

Emtsev, V. V., E-mail: emtsev@mail.ioffe.ru; Abrosimov, N. V.; Kozlovskii, V. V.

2016-10-15

Electrical properties of defects formed in n-Si(FZ) following 8 and 15 MeV proton irradiation are investigated by Hall effect measurements over the wide temperature range of T ≈ 25 to 300 K. Close attention is paid to the damaging factor of proton irradiation, leaving aside passivation effects by hydrogen. The concept of defect production and annealing processes being accepted in the literature so far needs to be reconsidered. Contrary to expectations the dominant impurity-related defects produced by MeV protons turn out to be electrically neutral in n-type material. Surprisingly, radiation acceptors appear to play a minor role. Annealing studies ofmore » irradiated samples of such complex defects as a divacancy tied to a phosphorus atom and a vacancy tied to two phosphorus atoms. The latter defect features high thermal stability. Identification of the dominant neutral donors, however, remains unclear and will require further, more detailed, studies. The electric properties of the material after proton irradiation can be completely restored at T = 800°C.« less

Bone-eating Osedax worms lived on Mesozoic marine reptile deadfalls.

PubMed

Danise, Silvia; Higgs, Nicholas D

2015-04-01

We report fossil traces of Osedax, a genus of siboglinid annelids that consume the skeletons of sunken vertebrates on the ocean floor, from early-Late Cretaceous (approx. 100 Myr) plesiosaur and sea turtle bones. Although plesiosaurs went extinct at the end-Cretaceous mass extinction (66 Myr), chelonioids survived the event and diversified, and thus provided sustenance for Osedax in the 20 Myr gap preceding the radiation of cetaceans, their main modern food source. This finding shows that marine reptile carcasses, before whales, played a key role in the evolution and dispersal of Osedax and confirms that its generalist ability of colonizing different vertebrate substrates, like fishes and marine birds, besides whale bones, is an ancestral trait. A Cretaceous age for unequivocal Osedax trace fossils also dates back to the Mesozoic the origin of the entire siboglinid family, which includes chemosynthetic tubeworms living at hydrothermal vents and seeps, contrary to phylogenetic estimations of a Late Mesozoic-Cenozoic origin (approx. 50-100 Myr). © 2015 The Author(s) Published by the Royal Society. All rights reserved.

Gestalt Group Dreamwork Demonstrations in Taiwan

ERIC Educational Resources Information Center

Coven, Arnold B.

2004-01-01

The application of Gestalt dreamwork was explored with counselor education students and professors at two Taiwan universities. The literature indicates Asians are reluctant to disclose personal matters or to display emotions. Contrary to expectations, the Taiwanese participants readily enacted roles, were personally open, and expressed intense…

Phenomenology of n - n ¯ oscillations revisited

DOE PAGES

Gardner, S.; Jafari, E.

2015-05-22

We revisit the phenomenology of n-n¯ oscillations in the presence of external magnetic fields, highlighting the role of spin. We show, contrary to long-held belief, that the n-n¯ transition rate need not be suppressed, opening new opportunities for its empirical study.

Phenomenology of n - n ¯ oscillations revisited

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

Gardner, S.; Jafari, E.

We revisit the phenomenology of n-n¯ oscillations in the presence of external magnetic fields, highlighting the role of spin. We show, contrary to long-held belief, that the n-n¯ transition rate need not be suppressed, opening new opportunities for its empirical study.

Shedding the Ego: Drama-Based Role-Play and Identity in Distance Language Tuition

ERIC Educational Resources Information Center

Brash, Barbel; Warnecke, Sylvia

2009-01-01

In this article, the authors attempt to answer the following questions: How do we understand role-play? How are role-play and identity linked? What are the purposes, benefits and challenges of role-play as a teaching tool? What are the roles of students and teachers in role-play? What does role-play add to telephone tutorials and online…

Creating a Development Support Bubble for Children

NASA Astrophysics Data System (ADS)

Verhaegh, Janneke; Fontijn, Willem; Aarts, Emile; Boer, Laurens; van de Wouw, Doortje

In this paper we describe an opportunity Ambient Intelligence provides outside the domains typically associated with it. We present a concept for enhancing child development by introducing tangible computing in a way that fits the children and improves current education. We argue that the interfaces used should be simple and make sense to the children. The computer should be hidden and interaction should take place through familiar play objects to which the children already have a connection. Contrary to a straightforward application of personal computers, our solution addresses cognitive, social and fine motor skills in an integrated manner. We illustrate our vision with a concrete example of an application that supports the inevitable transition from free play throughout the classroom to focused play at the table. We also present the validation of the concept with children, parents and teachers, highlighting that they all recognize the benefits of tangible computing in this domain.

Psychiatrists' Perceptions of Role-Playing Games.

PubMed

Lis, Eric; Chiniara, Carl; Biskin, Robert; Montoro, Richard

2015-09-01

The literature has seen a surge in research on the mental health impacts of technologies such as Facebook, video games, and massively-multiplayer online role-playing games such as World of Warcraft, but little is known regarding the mental health impact of non-video role-playing games, such as Dungeons & Dragons. The present study examines how psychiatrists' perceive role-playing games and whether they play them. Psychiatrists at a tertiary care centre in Canada completed a questionnaire assessing history of playing role-playing games and whether they associate them with psychopathology. Forty-eight psychiatrists responded. Twenty-three percent have played a role-playing game over their lifetimes. Twenty-two percent believed there was an association between psychopathology and role-playing games. A majority of psychiatrists who responded do not associate role-playing games with psychopathology. Implications for clinical practice and future research are discussed.

Decision making in the short and long run: repeated gambles and rationality.

PubMed

Aloysius, John A

2007-05-01

Experimental evidence indicates that decision makers who reject a single play of a gamble may accept repeated plays of that gamble. The rationality of this pattern of preference has been investigated beginning with Samuelson's colleague (SC) who gained notoriety in a well-known paper. SC's pattern of preference is commonly viewed as a behavioural anomaly. Researchers from branches of psychology and economics have analysed the choice and, despite much debate, there remains considerable confusion. An axiomatic analysis of SC's choice has been used to motivate experimental studies in several disciplines. This paper identifies the axiomatic violation as that of an assumed rather than a normative condition. Therefore, contrary to popular belief, SC's choice is consistent with expected utility theory.

Role of Social Presence and Cognitive Absorption in Online Learning Environments

ERIC Educational Resources Information Center

Leong, Peter

2011-01-01

This article investigates the relationships between social presence, cognitive absorption, interest, and student satisfaction in online learning. A hypothesized structural equation model was developed to study these critical variables that may influence interaction in online learning environments. Contrary to expectations, the study determined…

Organic Matter Sources Supporting Lower Food Web Production in the Tidal Freshwater Portion of the York River Estuary, Virginia

EPA Science Inventory

This manuscript presents novel findings on the role of terrestrial organic carbon in an estuary ecosystem. We show that, contrary to current thinking, terrestrial carbon can support the majority of secondary production in an estuary ecosystem.

Protective roles of single-wall carbon nanotubes in ultrasonication-induced DNA base damage.

PubMed

Petersen, Elijah J; Tu, Xiaomin; Dizdaroglu, Miral; Zheng, Ming; Nelson, Bryant C

2013-01-28

The overall level of ultrasonication-induced DNA damage is reduced in the presence of single-wall carbon nanotubes (SWCNTs), particularly for DNA lesions formed by one-electron reduction of intermediate radicals. The protective role of SWCNTs observed in this work suggests a contrary view to the general idea that carbon nanotubes have damaging effects on biomolecules. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Relationship between self-confidence and sex role identity among managerial women and men.

PubMed

Chusmir, L H; Koberg, C S

1991-12-01

The self-confidence and sex role identities of 437 American female and male managers were examined by using three subscales of the Adjective Check List. Results showed that, contrary to stereotypes and older research, female and male managers were strikingly similar. Women and men with cross-sex role identities showed lower levels of self-confidence than those did with androgynous orientations; high self-confidence was linked with masculine and androgynous orientations. The managers were not significantly different in self-confidence when demographic variables and sex role identity were held constant. Sex role identity (but not gender) was a major factor in the level of self-confidence.

How to Use (Not Abuse) Role Plays.

ERIC Educational Resources Information Center

Wright, Van O.

1989-01-01

Discusses the use of role plays in training for human communication skills, sales skills, and management skills. Rules for the application of role plays are given, steps in designing role plays are described, typical role play structures are explained, and materials for instructors and participants are discussed. (LRW)

Body mass index and depressive symptoms in older adults: the moderating roles of race, sex, and socioeconomic status.

PubMed

Sachs-Ericsson, Natalie; Burns, Andrea B; Gordon, Kathryn H; Eckel, Lisa A; Wonderlich, Steven A; Crosby, Ross D; Blazer, Dan G

2007-09-01

Although the long-term health risks associated with obesity in older adults have been well documented, less is known about the psychological consequences. The current study examined the relationship between body mass index (BMI) and subsequent depressive symptoms. The authors anticipated that BMI would predict depressive symptoms, and that this relationship would be greater among women, individuals of higher socioeconomic status (SES), and white subjects. A three-year longitudinal epidemiological design was employed. Participants were obtained from a biracial sample of community-dwelling older adults (N = 2,406) and were interviewed in their home by trained interviewers. A comprehensive survey assessed age, gender, race, SES (education and income), and health functioning variables. Depressive symptoms were assessed using the Center for Epidemiologic Studies Depression Scale. BMI was derived from self-reported weight and height. BMI was found to predict depressive symptoms. Contrary to predictions, the influence of BMI on depressive symptoms was greater for African Americans than whites and, in particular, African Americans with less education. There were no sex differences. Among older adults, BMI was associated with depressive symptoms although the effect size was small. Factors contributing to this relationship may differ from those observed in younger populations, for example, health functioning may play a larger role. Obesity appears to have the most adverse impact on those who are most likely to be overweight, lower SES African Americans.

The middle way of evolution

PubMed Central

Hunt, Tam

2012-01-01

This essay provides a critical review of two recent books on evolution: Richard Dawkins’ The Greatest Show on Earth, and Jerry Coyne’s Why Evolution is True, as well as a critique of mainstream evolutionary theory and of natural selection. I also suggest a generalization of sexual selection theory that acknowledges mind as pervasive in nature. Natural selection, as the primary theory of how biological change occurs, must be carefully framed to avoid the long-standing “tautology problem” and must also be modified to more explicitly include the role of mind in evolution. A propensity approach to natural selection, in which “expected fitness” is utilized rather than “fitness,” can save natural selection from tautology. But to be a productive theory, natural selection theory should be placed alongside sexual selection – which is explicitly agentic/intentional – as a twin force, but also placed alongside purely endogenous factors such as genetic drift. This framing is contrary to the normal convention that often groups all of these factors under the rubric of “natural selection.” I suggest some approaches for improving modern evolutionary theory, including a “generalized sexual selection,” a panpsychist extension of Darwin’s theory of sexual selection that explicitly recognizes the role of mind at all levels of nature and which may play the part of a general theory of evolution better than natural selection theory. PMID:23181154

Disruption of the Flnb gene in mice phenocopies the human disease spondylocarpotarsal synostosis syndrome.

PubMed

Farrington-Rock, Claire; Kirilova, Veneta; Dillard-Telm, Lisa; Borowsky, Alexander D; Chalk, Sara; Rock, Matthew J; Cohn, Daniel H; Krakow, Deborah

2008-03-01

Spondylocarpotarsal synostosis syndrome (SCT) is an autosomal recessive disease that is characterized by short stature, and fusions of the vertebrae and carpal and tarsal bones. SCT results from homozygosity or compound heterozygosity for nonsense mutations in FLNB. FLNB encodes filamin B, a multifunctional cytoplasmic protein that plays a critical role in skeletal development. Protein extracts derived from cells of SCT patients with nonsense mutations in FLNB did not contain filamin B, demonstrating that SCT results from absence of filamin B. To understand the role of filamin B in skeletal development, an Flnb-/- mouse model was generated. The Flnb-/- mice were phenotypically similar to individuals with SCT as they exhibited short stature and similar skeletal abnormalities. Newborn Flnb-/- mice had fusions between the neural arches of the vertebrae in the cervical and thoracic spine. At postnatal day 60, the vertebral fusions were more widespread and involved the vertebral bodies as well as the neural arches. In addition, fusions were seen in sternum and carpal bones. Analysis of the Flnb-/- mice phenotype showed that an absence of filamin B causes progressive vertebral fusions, which is contrary to the previous hypothesis that SCT results from failure of normal spinal segmentation. These findings suggest that spinal segmentation can occur normally in the absence of filamin B, but the protein is required for maintenance of intervertebral, carpal and sternal joints, and the joint fusion process commences antenatally.

Stable solid and aqueous H2CO3 from CO2 and H2O at high pressure and high temperature

NASA Astrophysics Data System (ADS)

Wang, Hongbo; Zeuschner, Janek; Eremets, Mikhail; Troyan, Ivan; Willams, Jonathan

2016-01-01

Carbonic acid (H2CO3) forms in small amounts when CO2 dissolves in H2O, yet decomposes rapidly under ambient conditions of temperature and pressure. Despite its fleeting existence, H2CO3 plays an important role in the global carbon cycle and in biological carbonate-containing systems. The short lifetime in water and presumed low concentration under all terrestrial conditions has stifled study of this fundamental species. Here, we have examined CO2/H2O mixtures under conditions of high pressure and high temperature to explore the potential for reaction to H2CO3 inside celestial bodies. We present a novel method to prepare solid H2CO3 by heating CO2/H2O mixtures at high pressure with a CO2 laser. Furthermore, we found that, contrary to present understanding, neutral H2CO3 is a significant component in aqueous CO2 solutions above 2.4 GPa and 110 °C as identified by IR-absorption and Raman spectroscopy. This is highly significant for speciation of deep C-O-H fluids with potential consequences for fluid-carbonate-bearing rock interactions. As conditions inside subduction zones on Earth appear to be most favorable for production of aqueous H2CO3, a role in subduction related phenomena is inferred.

The role of emotional capital during the early years of marriage: Why everyday moments matter.

PubMed

Walsh, Courtney M; Neff, Lisa A; Gleason, Marci E J

2017-06-01

Throughout a marriage couples will share countless ordinary moments together that may seem trivial, but which actually have potential to affirm and strengthen relational bonds. According to theories of emotional capital, the accumulation of shared positive moments in a relationship should serve as an essential resource for protecting the relationship against threats. To date, however, few empirical studies have explored the role emotional capital may play in shaping responses to negative relationship experiences. In the current study, newly married couples completed 3 14-day daily diary tasks assessing emotional capital, negative partner behaviors, and marital satisfaction over a 3-year period, for a total of 42 potential days of diary data. Contrary to predictions, emotional capital on a given day was not associated with reactivity to relationship threats on the following day. However, conceptually replicating prior work, individuals who accumulated more emotional capital on average across the diary tasks did exhibit lower reactivity to daily relationship threats; that is, on days of greater relationship threat (i.e., negative partner behaviors), those spouses who generally accrued more shared positive moments with their partner maintained greater feelings of marital satisfaction compared with spouses who accrued fewer positive moments. These findings contribute to a growing literature illustrating how positive shared activities between partners help sustain relationship quality over time. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Apoptotic microtubule network organization and maintenance depend on high cellular ATP levels and energized mitochondria.

PubMed

Oropesa, Manuel; de la Mata, Mario; Maraver, Juan Garrido; Cordero, Mario D; Cotán, David; Rodríguez-Hernández, Angeles; Domínguez-Moñino, Irene; de Miguel, Manuel; Navas, Plácido; Sánchez-Alcázar, José A

2011-04-01

Microtubule cytoskeleton is reformed during apoptosis, forming a cortical structure beneath plasma membrane, which plays an important role in preserving cell morphology and plasma membrane integrity. However, the maintenance of the apoptotic microtubule network (AMN) during apoptosis is not understood. In the present study, we examined apoptosis induced by camptothecin (CPT), a topoisomerase I inhibitor, in human H460 and porcine LLCPK-1α cells. We demonstrate that AMN was organized in apoptotic cells with high ATP levels and hyperpolarized mitochondria and, on the contrary, was dismantled in apoptotic cells with low ATP levels and mitochondrial depolarization. AMN disorganization after mitochondrial depolarization was associated with increased plasma membrane permeability assessed by enhancing LDH release and increased intracellular calcium levels. Living cell imaging monitoring of both, microtubule dynamics and mitochondrial membrane potential, showed that AMN persists during apoptosis coinciding with cycles of mitochondrial hyperpolarization. Eventually, AMN was disorganized when mitochondria suffered a large depolarization and cell underwent secondary necrosis. AMN stabilization by taxol prevented LDH release and calcium influx even though mitochondria were depolarized, suggesting that AMN is essential for plasma membrane integrity. Furthermore, high ATP levels and mitochondria polarization collapse after oligomycin treatment in apoptotic cells suggest that ATP synthase works in "reverse" mode during apoptosis. These data provide new explanations for the role of AMN and mitochondria during apoptosis.

Comprehensive interactome of Otx2 in the adult mouse neural retina.

PubMed

Fant, Bruno; Samuel, Alexander; Audebert, Stéphane; Couzon, Agnès; El Nagar, Salsabiel; Billon, Nathalie; Lamonerie, Thomas

2015-11-01

The Otx2 homeodomain transcription factor exerts multiple functions in specific developmental contexts, probably through the regulation of different sets of genes. Protein partners of Otx2 have been shown to modulate its activity. Therefore, the Otx2 interactome may play a key role in selecting a precise target-gene repertoire, hence determining its function in a specific tissue. To address the nature of Otx2 interactome, we generated a new recombinant Otx2(CTAP-tag) mouse line, designed for protein complexes purification. We validated this mouse line by establishing the Otx2 interactome in the adult neural retina. In this tissue, Otx2 is thought to have overlapping function with its paralog Crx. Our analysis revealed that, in contrary to Crx, Otx2 did not develop interactions with proteins that are known to regulate phototransduction genes but showed specific partnership with factors associated with retinal development. The relationship between Otx2 and Crx in the neural retina should therefore be considered as complementarity rather than redundancy. Furthermore, study of the Otx2 interactome revealed strong associations with RNA processing and translation machineries, suggesting unexpected roles for Otx2 in the regulation of selected target genes all along the transcription/translation pathway. The Otx2(CTAP-tag) line, therefore, appears suitable for a systematic approach to Otx2 protein-protein interactions. genesis 53:685-694, 2015. © 2015 Wiley Periodicals, Inc. © 2015 Wiley Periodicals, Inc.

Recognition of Artificial Nucleobases by E. coli Purine Nucleoside Phosphorylase versus its Ser90Ala Mutant in the Synthesis of Base-Modified Nucleosides.

PubMed

Fateev, Ilja V; Kharitonova, Maria I; Antonov, Konstantin V; Konstantinova, Irina D; Stepanenko, Vasily N; Esipov, Roman S; Seela, Frank; Temburnikar, Kartik W; Seley-Radtke, Katherine L; Stepchenko, Vladimir A; Sokolov, Yuri A; Miroshnikov, Anatoly I; Mikhailopulo, Igor A

2015-09-14

A wide range of natural purine analogues was used as probe to assess the mechanism of recognition by the wild-type (WT) E. coli purine nucleoside phosphorylase (PNP) versus its Ser90Ala mutant. The results were analyzed from viewpoint of the role of the Ser90 residue and the structural features of the bases. It was found that the Ser90 residue of the PNP 1) plays an important role in the binding and activation of 8-aza-7-deazapurines in the synthesis of their nucleosides, 2) participates in the binding of α-D-pentofuranose-1-phosphates at the catalytic site of the PNP, and 3) catalyzes the dephosphorylation of intermediary formed 2-deoxy-α-D-ribofuranose-1-phosphate in the trans-2-deoxyribosylation reaction. 5-Aza-7-deazaguanine manifested excellent substrate activity for both enzymes, 8-amino-7-thiaguanine and 2-aminobenzothiazole showed no substrate activity for both enzymes. On the contrary, the 2-amino derivatives of benzimidazole and benzoxazole are substrates and are converted into the N1- and unusual N2-glycosides, respectively. 9-Deaza-5-iodoxanthine showed moderate inhibitory activity of the WT E. coli PNP, whereas 9-deazaxanthine and its 2'-deoxyriboside are weak inhibitors. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Impact of neutrophil-secreted myeloid related proteins 8 and 14 (MRP 8/14) on leishmaniasis progression.

PubMed

Contreras, Irazú; Shio, Marina T; Cesaro, Annabelle; Tessier, Philippe A; Olivier, Martin

2013-01-01

The myeloid-related proteins (MRPs) 8/14 are small proteins mainly produced by neutrophils, which have been reported to induce NO production in macrophages. On the other hand, Leishmania survives and multiplies within phagocytes by inactivating several of their microbicidal functions. Whereas MRPs are rapidly released during the innate immune response, their role in the regulation of Leishmaniasis is still unknown. In vitro experiments revealed that Leishmania infection alters MRP-induced signaling, leading to inhibition of macrophage functions (NO, TNF-α). In contrast, MRP-primed cells showed normal signaling activation and NO production in response to Leishmania infection. Using a murine air-pouch model, we observed that infection with L. major induced leukocyte recruitment and MRP secretion comparable to LPS-treated mice. Depletion of MRPs significantly reduced these inflammatory events and augmented both parasite load and footpad swelling during the first 8 weeks post-infection, as also observed in MRP KO mice. On the contrary, mouse treatment with recombinant MRPs (rMRPs) had the opposite effect. Collectively, our results suggest that rapid secretion of MRPs by neutrophils at the site of infection may protect uninfected macrophages and favor a more efficient innate inflammatory response against Leishmania infection. In summary, our study reveals the critical role played by MRPs in the regulation of Leishmania infection and how this pathogen can subvert its action.

Impact of Neutrophil-Secreted Myeloid Related Proteins 8 and 14 (MRP 8/14) on Leishmaniasis Progression

PubMed Central

Contreras, Irazú; Shio, Marina T.; Cesaro, Annabelle; Tessier, Philippe A.; Olivier, Martin

2013-01-01

The myeloid-related proteins (MRPs) 8/14 are small proteins mainly produced by neutrophils, which have been reported to induce NO production in macrophages. On the other hand, Leishmania survives and multiplies within phagocytes by inactivating several of their microbicidal functions. Whereas MRPs are rapidly released during the innate immune response, their role in the regulation of Leishmaniasis is still unknown. In vitro experiments revealed that Leishmania infection alters MRP-induced signaling, leading to inhibition of macrophage functions (NO, TNF-α). In contrast, MRP-primed cells showed normal signaling activation and NO production in response to Leishmania infection. Using a murine air-pouch model, we observed that infection with L. major induced leukocyte recruitment and MRP secretion comparable to LPS-treated mice. Depletion of MRPs significantly reduced these inflammatory events and augmented both parasite load and footpad swelling during the first 8 weeks post-infection, as also observed in MRP KO mice. On the contrary, mouse treatment with recombinant MRPs (rMRPs) had the opposite effect. Collectively, our results suggest that rapid secretion of MRPs by neutrophils at the site of infection may protect uninfected macrophages and favor a more efficient innate inflammatory response against Leishmania infection. In summary, our study reveals the critical role played by MRPs in the regulation of Leishmania infection and how this pathogen can subvert its action. PMID:24086787

Expression studies of the PIS-regulated genes suggest different mechanisms of sex determination within mammals.

PubMed

Pannetier, M; Servel, N; Cocquet, J; Besnard, N; Cotinot, C; Pailhoux, E

2003-01-01

In mammals, the Y-located SRY gene is known to induce testis formation from the indifferent gonad. A related gene, SOX9, also plays a critical role in testis differentiation in mammals, in birds and reptiles. It is now assumed that SRY acts upstream of SOX9 in the sex determination cascade, but the regulatory link which should exist between these two genes remains unknown. Studies on XX sex reversal in polled goats (PIS mutation: Polled Intersex Syndrome) have led to the discovery of a female-specific locus crucial for ovarian differentiation. This genomic region is composed of at least two genes, FOXL2 and PISRT1, which share a common transcriptional regulatory region, PIS. In this review, we present the expression pattern of these PIS-regulated genes in mice. The FOXL2 expression profile of mice is similar to that described in goats in accordance with a conserved role of this ovarian differentiating gene in mammals. On the contrary, the PISRT1 expression profile is different between mice and goats, suggesting different mechanisms of the primary switch in the testis determination process within mammals. A model based on two different modes of SOX9 regulation in mice and other mammals is proposed in order to integrate our results into the current scheme of gonad differentiation. Copyright 2003 S. Karger AG, Basel

Stable solid and aqueous H2CO3 from CO2 and H2O at high pressure and high temperature

PubMed Central

Wang, Hongbo; Zeuschner, Janek; Eremets, Mikhail; Troyan, Ivan; Willams, Jonathan

2016-01-01

Carbonic acid (H2CO3) forms in small amounts when CO2 dissolves in H2O, yet decomposes rapidly under ambient conditions of temperature and pressure. Despite its fleeting existence, H2CO3 plays an important role in the global carbon cycle and in biological carbonate-containing systems. The short lifetime in water and presumed low concentration under all terrestrial conditions has stifled study of this fundamental species. Here, we have examined CO2/H2O mixtures under conditions of high pressure and high temperature to explore the potential for reaction to H2CO3 inside celestial bodies. We present a novel method to prepare solid H2CO3 by heating CO2/H2O mixtures at high pressure with a CO2 laser. Furthermore, we found that, contrary to present understanding, neutral H2CO3 is a significant component in aqueous CO2 solutions above 2.4 GPa and 110 °C as identified by IR-absorption and Raman spectroscopy. This is highly significant for speciation of deep C–O–H fluids with potential consequences for fluid-carbonate-bearing rock interactions. As conditions inside subduction zones on Earth appear to be most favorable for production of aqueous H2CO3, a role in subduction related phenomena is inferred. PMID:26813580

Stable solid and aqueous H2CO3 from CO2 and H2O at high pressure and high temperature.

PubMed

Wang, Hongbo; Zeuschner, Janek; Eremets, Mikhail; Troyan, Ivan; Willams, Jonathan

2016-01-27

Carbonic acid (H2CO3) forms in small amounts when CO2 dissolves in H2O, yet decomposes rapidly under ambient conditions of temperature and pressure. Despite its fleeting existence, H2CO3 plays an important role in the global carbon cycle and in biological carbonate-containing systems. The short lifetime in water and presumed low concentration under all terrestrial conditions has stifled study of this fundamental species. Here, we have examined CO2/H2O mixtures under conditions of high pressure and high temperature to explore the potential for reaction to H2CO3 inside celestial bodies. We present a novel method to prepare solid H2CO3 by heating CO2/H2O mixtures at high pressure with a CO2 laser. Furthermore, we found that, contrary to present understanding, neutral H2CO3 is a significant component in aqueous CO2 solutions above 2.4 GPa and 110 °C as identified by IR-absorption and Raman spectroscopy. This is highly significant for speciation of deep C-O-H fluids with potential consequences for fluid-carbonate-bearing rock interactions. As conditions inside subduction zones on Earth appear to be most favorable for production of aqueous H2CO3, a role in subduction related phenomena is inferred.

Fault zone structure and fluid-rock interaction of a high angle normal fault in Carrara marble (NW Tuscany, Italy)

NASA Astrophysics Data System (ADS)

Molli, G.; Cortecci, G.; Vaselli, L.; Ottria, G.; Cortopassi, A.; Dinelli, E.; Mussi, M.; Barbieri, M.

2010-09-01

We studied the geometry, intensity of deformation and fluid-rock interaction of a high angle normal fault within Carrara marble in the Alpi Apuane NW Tuscany, Italy. The fault is comprised of a core bounded by two major, non-parallel slip surfaces. The fault core, marked by crush breccia and cataclasites, asymmetrically grades to the host protolith through a damage zone, which is well developed only in the footwall block. On the contrary, the transition from the fault core to the hangingwall protolith is sharply defined by the upper main slip surface. Faulting was associated with fluid-rock interaction, as evidenced by kinematically related veins observable in the damage zone and fluid channelling within the fault core, where an orange-brownish cataclasite matrix can be observed. A chemical and isotopic study of veins and different structural elements of the fault zone (protolith, damage zone and fault core), including a mathematical model, was performed to document type, role, and activity of fluid-rock interactions during deformation. The results of our studies suggested that deformation pattern was mainly controlled by processes associated with a linking-damage zone at a fault tip, development of a fault core, localization and channelling of fluids within the fault zone. Syn-kinematic microstructural modification of calcite microfabric possibly played a role in confining fluid percolation.

Sustain talk predicts poorer outcomes among mandated college student drinkers receiving a brief motivational intervention.

PubMed

Apodaca, Timothy R; Borsari, Brian; Jackson, Kristina M; Magill, Molly; Longabaugh, Richard; Mastroleo, Nadine R; Barnett, Nancy P

2014-09-01

Within-session client language that represents a movement toward behavior change (change talk) has been linked to better treatment outcomes in the literature on motivational interviewing (MI). There has been somewhat less study of the impact of client language against change (sustain talk) on outcomes following an MI session. This study examined the role of both client change talk and sustain talk, as well as therapist language, occurring during a brief motivational intervention (BMI) session with college students who had violated college alcohol policy (N = 92). Audiotapes of these sessions were coded using a therapy process coding system. A series of hierarchical regressions were used to examine the relationships among therapist MI-consistent and MI-inconsistent language, client change talk and sustain talk, as well as global measures of relational variables, and drinking outcomes. Contrary to prior research, sustain talk, but not change talk, predicted poorer alcohol use outcomes following the BMI at 3- and 12-month follow-up assessments. Higher levels of client self-exploration during the session also predicted improved drinking outcomes. Therapist measures of MI-consistent and MI-inconsistent language, and global measures of therapist acceptance and MI spirit were unrelated to client drinking outcomes. Results suggest that client sustain talk and self-exploration during the session play an important role in determining drinking outcomes among mandated college students receiving a BMI addressing alcohol use.

Ischemia-reperfusion of human skeletal muscle during aortoiliac surgery: effects of acetylcarnitine.

PubMed

Adembri, C; Domenici, L L; Formigli, L; Brunelleschi, S; Ferrari, E; Novelli, G P

1994-10-01

Our previous study on human skeletal muscle undergoing ischemia and reperfusion has revealed that granulocytes, which infiltrate the muscle tissue in large numbers, play an important role in mediating fibre injuries by producing superoxide anion (O2-) which is responsible for membrane lipid peroxidation. In the current study, five patients undergoing aortic reconstructive surgery were given acetyl-carnitine (2 mg/kg i.v. plus 1 mg/kg/min for 30 min) prior to the induction of ischemia. Muscle biopsies and blood samples were examined: a) after anaesthesia; b) at the end of ischemia; and c) 30 min after reperfusion, with the aim of elucidating whether acetylcarnitine could prevent the infiltration and/or the activation of granulocytes and eventually skeletal muscle injuries. During ischemia and reperfusion complement activation recruited numerous granulocytes into the muscle tissue, but, contrary to the untreated samples, the ability for O2(-)-generation of these cells remained at low levels and was comparable to that of ischemia even when molecular O2 was reintroduced to the tissue. Accordingly, the morphological changes of the postischemic muscle fibers were substantially reduced when compared to the untreated samples; in fact, the mitochondrial swelling was only moderate and the intramitochondrial dense bodies were small and scarce. The current findings support a positive role of acetyl-carnitine in ameliorating the ischemia-reperfusion (I-R)-induced damage of human skeletal muscle.

Real and hypothetical endowment effects when exchanging lottery tickets: Is regret a better explanation than loss aversion?☆

PubMed Central

Kogler, Christoph; Kühberger, Anton; Gilhofer, Rainer

2013-01-01

The endowment effect is the finding that possession of an item adds to its value. We introduce a new procedure for testing this effect: participants are divided into two groups. Possession group participants inspect a numbered lottery ticket and know it is theirs, while inspection group participants only inspect a lottery ticket without being endowed with it. Subsequently participants choose between playing the lottery with this (possessed or inspected) ticket, or exchanging it for another one. Our procedure tests for the effect of endowment while controlling for the influence of transaction costs as well as for inspection effects and the influence of bargaining roles (buyer vs. seller), which often afflict experimentation with the endowment effect. In a real setting, tickets in possession were valued significantly higher than inspected tickets. Contrary to some findings in the literature participants also correctly predicted these valuation differences in a hypothetical situation, both for themselves as well as for others. Furthermore, our results suggest that regret rather than loss aversion may be the source of the endowment effect in an experimental setting using lottery tickets. Applying our procedure to a setting employing riskless objects in form of mugs revealed rather ambiguous results, thus emphasizing that the role of regret might be less prominent in non-lottery settings. PMID:23913998

Is The Modern Lease a Contract or a Conveyance?--A Historical Inquiry

ERIC Educational Resources Information Center

Siegel, Stephen A.

1975-01-01

Argues that "contrary to conventional wisdom, current landlord-tenant law is modern, commercial, and already grounded in contract doctrine." Discusses the origins of the doctrines most frequently cited as illustrations of leasings property basis and redevelops the role of property law in adjudicating leasing disputes. (JT)

The Relationship between Career Motivation and Self-Efficacy with Protege Career Success

ERIC Educational Resources Information Center

Day, Rachel; Allen, Tammy D.

2004-01-01

Research exploring the underlying processes involved in successful mentorships has been lacking. In the present study, the roles of career motivation and career self-efficacy as explanatory factors were examined. Career motivation mediated the relationship between career mentoring and performance effectiveness. Contrary to prediction, only…

The Personal Orientation Inventory As A Predictor Of Resident Assistant Effectiveness

ERIC Educational Resources Information Center

Atkinson, Donald R.; And Others

1973-01-01

The results of this study, contrary to findings in earlier studies, do not support use of the Personal Orientation Inventory as an instrument for selecting effective resident assistants. Evidence was found that hall residents feel resident assistants are more effective in some roles than others. (Author)

Profiling caregivers: Hormonal variation underlying allomaternal care in wild red-bellied lemurs, Eulemur rubriventer.

PubMed

Tecot, Stacey R; Baden, Andrea L

2018-05-02

Neuroendocrine evidence suggests that paternal care is mediated by hormonal mechanisms, where hormonal changes in expectant and new fathers facilitate infant care. In species with obligate and extensive paternal care such as humans, androgen levels decline once males are paired and have offspring, and in direct response to offspring care. Facultative infant care is widespread in the Order Primates, but the underlying hormonal mechanisms are largely unknown. We found that wild, red-bellied lemurs living in family groups (two adults and their presumed offspring) varied in the amount of care they provided infants. The more fathers invested in helping infants (measured as a composite of carrying, holding, huddling, grooming, and playing), and specifically the more they huddled and groomed with infants, the higher their fecal androgen (fA) levels, contrary to expectations. Carrying was negatively related to fA levels. Helping by subadults and juveniles was not related to their own fA levels. Elevated fA levels during infant dependence have been observed in other vertebrate species, and are thought to reflect reinvestment in mating rather than investment in dependent offspring. However, red-bellied lemurs do not mate until after infants are weaned, and they have long-term pair-bonds, suggesting that elevated fA levels play a role in offspring care. These results support a growing body of research suggesting that elevated androgen levels do not inhibit protective infant care. Copyright © 2017 Elsevier Inc. All rights reserved.

Intranasal administration of oxytocin increases envy and schadenfreude (gloating).

PubMed

Shamay-Tsoory, Simone G; Fischer, Meytal; Dvash, Jonathan; Harari, Hagai; Perach-Bloom, Nufar; Levkovitz, Yechiel

2009-11-01

Humans have a strong social tendency to compare themselves with others. We tend to feel envious when we receive less valuable rewards and may rejoice when our payoffs are more advantageous. Envy and schadenfreude (gloating over the other's misfortune) are social emotions widely agreed to be a symptom of the human social tendency to compare one's payoffs with those of others. Given the important social components of envy and gloating, we speculated that oxytocin may have a modulating effect on the intensity of these emotions. Fifty-six participants participated in this double-blind, placebo-controlled, within-subject study. Following the administration of oxytocin or a placebo, participants played a game of chance with another (fake) participant who either won more money (envy manipulation), lost more money (schadenfreude manipulation), or won/lost equal amounts of money. In comparison with the placebo, oxytocin increased the envy ratings during unequal monetary gain conditions involving relative loss (when the participant gained less money than another player). Oxytocin also increased the ratings of gloating during relative gain conditions (when the participant gained more money than the other player). By contrast, oxytocin had no effect on the emotional ratings following equal monetary gains nor did it affect general mood ratings. These results suggest that the oxytocinergic system is involved in modulating envy and gloating. Thus, contrary to the prevailing belief that this system is involved solely in positive prosocial behaviors, it probably plays a key role in a wider range of social emotion-related behaviors.

Abstract semantics in the motor system? - An event-related fMRI study on passive reading of semantic word categories carrying abstract emotional and mental meaning.

PubMed

Dreyer, Felix R; Pulvermüller, Friedemann

2018-03-01

Previous research showed that modality-preferential sensorimotor areas are relevant for processing concrete words used to speak about actions. However, whether modality-preferential areas also play a role for abstract words is still under debate. Whereas recent functional magnetic resonance imaging (fMRI) studies suggest an involvement of motor cortex in processing the meaning of abstract emotion words as, for example, 'love', other non-emotional abstract words, in particular 'mental words', such as 'thought' or 'logic', are believed to engage 'amodal' semantic systems only. In the present event-related fMRI experiment, subjects passively read abstract emotional and mental nouns along with concrete action related words. Contrary to expectation, the results indicate a specific involvement of face motor areas in the processing of mental nouns, resembling that seen for face related action words. This result was confirmed when subject-specific regions of interest (ROIs) defined by motor localizers were used. We conclude that a role of motor systems in semantic processing is not restricted to concrete words but extends to at least some abstract mental symbols previously thought to be entirely 'disembodied' and divorced from semantically related sensorimotor processing. Implications for neurocognitive theories of semantics and clinical applications will be highlighted, paying specific attention to the role of brain activations as indexes of cognitive processes and their relationships to 'causal' studies addressing lesion and transcranial magnetic stimulation (TMS) effects. Possible implications for clinical practice, in particular speech language therapy, are discussed in closing. Copyright © 2017. Published by Elsevier Ltd.

Psychometrics in Psychological Research: Role Model or Partner in Science?

ERIC Educational Resources Information Center

Sijtsma, Klaas

2006-01-01

This is a reaction to Borsboom's (2006) discussion paper on the issue that psychology takes so little notice of the modern developments in psychometrics, in particular, latent variable methods. Contrary to Borsboom, it is argued that latent variables are summaries of interesting data properties, that construct validation should involve studying…

The Power of "We" Language in Creating Equitable Learning Environments

ERIC Educational Resources Information Center

Erb, Cathy Smeltzer

2010-01-01

Effective teaching values the classroom as a learning community in which instructional approaches optimize learning for all students. Contrary to the principles of an equitable learning environment is the use of "me" language by teachers, a practice that promotes the role of teacher as high status and inadvertently excludes students from the…

Genderlects: A Brief Review of the Literature.

ERIC Educational Resources Information Center

Edelsky, Carole

Stereotypes about the way women talk grow out of knowledge of nonlinguistic, societally assigned sex role traits and of linguistic correlates of those traits. Among the findings of research on male/female speech differences are that, contrary to the stereotype, men talk more than women; men's conversation is task-oriented, while that of women is…

Dancing with Eyes Wide Open: On the Role of Nostalgia in Education

ERIC Educational Resources Information Center

Halpin, David

2016-01-01

Nostalgia rightly elicits suspicion, even derision, for to give oneself up to longing for something from the past runs the risk of compromising one's capacity to act effectively in the present. But this does not make nostalgia, "by definition," either sentimentally reactionary or wistfully unreflective. On the contrary, in the education…

The Role of Cognitive Disposition in Re-Examining the Privacy Paradox: A Neuroscience Study

ERIC Educational Resources Information Center

Mohammed, Zareef

2017-01-01

The privacy paradox is a phenomenon whereby individuals continue to disclose their personal information, contrary to their claim of concerns for the privacy of their personal information. This study investigated the privacy paradox to better understand individuals' decisions to disclose or withhold their personal information. The study argued that…

Emotional Intelligence: A Moderator of Perceived Alcohol Peer Norms and Alcohol Use

ERIC Educational Resources Information Center

Ghee, Anna Cash; Johnson, Candace S.

2008-01-01

This study investigated the roles of emotional intelligence and perceived alcohol peer norms in relation to alcohol use. Two hundred and forty--two undergraduates completed the Campus Survey of Alcohol and Other Drug Norms (Core Institute, 1997) and the Emotional Intelligence Scale (Schutte, Malouff, Hall, Haggerty, & Cooper, 1998). Contrary to…

Partners in Economic Development: Community College Strategies for Collaboration.

ERIC Educational Resources Information Center

Ryan, G. Jeremiah, Ed.

In response to the competitive challenges of the emerging world economy, employers are looking increasingly to community colleges for the provision of job training to revitalize their work forces. While job training is an appropriate role for community colleges, its delivery, characterized by speed and adaptability, is contrary to most campus…

Gender Differences in Cambodian Delinquency: The Role of Ethnic Identity, Parental Discipline, and Peer Delinquency

ERIC Educational Resources Information Center

Go, Charles G.; Le, Thao N.

2005-01-01

Contrary to the model minority stereotype, Asian youth are increasingly becoming more involved in crime and delinquency. For instance, in the California Youth Authority, Southeast Asian adolescents are disproportionately represented, including Cambodian, Hmong, and Lao and Mien youth. However, few studies have focused on factors that are…

Integration of role-playing into technical skills training: a randomized controlled trial.

PubMed

Nikendei, C; Kraus, B; Schrauth, M; Weyrich, P; Zipfel, S; Herzog, W; Jünger, J

2007-11-01

Recently, efforts have been undertaken to enhance the face validity of technical skills training by introducing role-plays and standardised patients. Since little is known about the effects of role-playing with respect to the realism of a training situation and students' objective performance, we performed a randomized controlled trial. 36 medical students participated in videotaped small group skills-lab sessions on the topics of Doppler sonography and gastric tube insertion. One half of the students participated in role-plays and the other half practised without role-playing. Realism of the training situation was analysed by means of post-intervention self-selected student survey evaluations. Technical performance and patient-physician communication were assessed by independent ratings of the videotaped sessions. The physician's role was regarded to be significantly more realistic when performing role-plays. Assessment of videotaped sessions showed that practising technical skills by performing role-plays resulted in significantly better patient-physician communication whereas students' technical performance did not differ between groups. Introducing role-plays enhances the realism of technical skills training and leads to better patient-physician communication. Students do not seem to be overstrained by practising clinical technical skills using role-plays. We conclude that role-playing is a valuable method in practising technical skills.

Using Online Role-Play to Promote Collaborative Argument and Collective Action

ERIC Educational Resources Information Center

Doerr-Stevens, Candance; Beach, Richard; Boeser, Elizabeth

2011-01-01

This article discusses how students use online role-play to collaborate and change real school policy. Playing different characters in an online role-play, students explore controversial aspects of Internet filtering and adopt a plan to change their school's policy. Through engaging in collaborative argumentation during their role-play, students…

Correlation between IL-17A/F, IL-23, IL-35 and IL-12/-23 (p40) levels in peripheral blood lymphocyte cultures and disease activity in Behcet's patients.

PubMed

Sonmez, Cemile; Yucel, Aysegul Atak; Yesil, Turan Hilmi; Kucuk, Hamit; Sezgin, Berna; Mercan, Ridvan; Yucel, Ahmet Eftal; Demirel, Gulderen Yanikkaya

2018-03-20

Behcet's disease is a chronic multisystemic disease with remissions and relapses. Several studies have shown that immune mechanisms play an important role in the development of the disease. In order to assess the association of disease activity with IL-17A/F, IL-23, IL-12/23 (p40) and IL-35 expression, we aimed to investigate production of these cytokines in peripheral blood mononuclear cells (PBMCs) from Behcet's patients and normal controls. Furthermore, we included Systemic Lupus Erythematosus (SLE) as disease control to evaluate the specificity of our data for immunopathogenesis of BD. Totally 15 active, 15 inactive Behcet's patients, 12 active and 12 inactive SLE patients and 12 healthy volunteers were enrolled in the study. Peripheral blood mononuclear cells were separated, lymphocyte cultures were performed and IL-17A/F, IL-12/23 p(40), IL-23, IL-35 cytokine levels were measured by ELISA in culture supernatants in the presence or absence of phytohemagglutinin (PHA) on time-dependent manner. IL-17 A/F levels increased parallel to IL-23 levels in Behcet's and SLE patients. Compared to healthy controls, IL-17 A/F levels were higher in active Behcet's and SLE patients; on the contrary, levels of IL-35 were lower. IL-17A/F, IL-12/23 (p40) and IL-23 levels were detectable most frequently in active Behcet's patients followed by active SLE patients. Our results indicate that IL-17 A/F, IL-23 and IL-12/23 (p40) may play role in the immunopathogenesis of BD so as Th17 and Th1 cell responses. Since IL-35 levels were lower in active Behcet's patients compared to inactive patients and healthy controls, there may be a plasticity between Th17 and Treg cells according to the state of disease activity.

The Recipe for Corporate Longevity: From the Perspective of "Managing Innovation".

PubMed

Griesar, Klaus; Bessant, John; Bernschneider-Reif, Sabine

2018-04-09

The elephant is in the room-a metaphorical idiom for an obvious problem or risk that nobody wants to discuss. This abstract is not intended to be a summary, to reveal major findings, or unveil conclusions. On the contrary, it is aimed to provoke curiosity as to the question of corporate survival. Is there any recipe to be followed for companies to achieve this? The answer comes neither from the modest and traditional study rooms of philosophers nor the recent fact-based studies from the offices (and well-paid opinions) of business consultants. The Archimedean point from which we can objectively explore the subject of corporate survival does not exist. Instead we offer seven analogies (or metaphors) as intellectual platforms where new perspectives can be considered. Innovation obviously plays a major role in corporate survival-yet, by its nature all innovation is messy. In order to reduce entropy, this abstract reveals some keywords in alphabetical order starting from A, such as ambidexterity, architecture, and ant colonies, moving on to B, such as, (mental) boxes and biodiversity. For obvious reasons, C plays a major role-sufficiently that we have already revealed curiosity as one part of the answer-treading over to D (Darwin, DNA, and discontinuity), followed by E (earthquakes and evolution). As a final warning signal in order to manage the expectation: It is not the intention of this article to give a comprehensive overview about the rich and complex history of Merck KGaA, Darmstadt, Germany. Indeed, only the final chapter will provide reference to this company: Before the curtains will finally close, an epilogue will start in which one of the protagonists of the 350-year journey of the company-Emanuel Merck-will appear on the stage and "let history speak for itself". Still curious? © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Nematode-associated microbial taxa do not correlate with host phylogeny, geographic region or feeding morphology in marine sediment habitats.

PubMed

Schuelke, Taruna; Pereira, Tiago José; Hardy, Sarah M; Bik, Holly M

2018-04-01

Studies of host-associated microbes are critical for advancing our understanding of ecology and evolution across diverse taxa and ecosystems. Nematode worms are ubiquitous across most habitats on earth, yet little is known about host-associated microbial assemblages within the phylum. Free-living nematodes are globally abundant and diverse in marine sediments, with species exhibiting distinct buccal cavity (mouth) morphologies that are thought to play an important role in feeding ecology and life history strategies. Here, we investigated patterns in marine nematode microbiomes, by characterizing host-associated microbial taxa in 281 worms isolated from a range of habitat types (deep-sea, shallow water, methane seeps, Lophelia coral mounds, kelp holdfasts) across three distinct geographic regions (Arctic, Southern California and Gulf of Mexico). Microbiome profiles were generated from single worms spanning 33 distinct morphological genera, using a two-gene metabarcoding approach to amplify the V4 region of the 16S ribosomal RNA (rRNA) gene targeting bacteria/archaea and the V1-V2 region of the 18S rRNA gene targeting microbial eukaryotes. Contrary to our expectations, nematode microbiome profiles demonstrated no distinct patterns either globally (across depths and ocean basins) or locally (within site); prokaryotic and eukaryotic microbial assemblages did not correlate with nematode feeding morphology, host phylogeny or morphological identity, ocean region or marine habitat type. However, fine-scale analysis of nematode microbiomes revealed a variety of novel ecological interactions, including putative parasites and symbionts, and potential associations with bacterial/archaeal taxa involved in nitrogen and methane cycling. Our results suggest that in marine habitats, free-living nematodes may utilize diverse and generalist foraging strategies that are not correlated with host genotype or feeding morphology. Furthermore, some abiotic factors such as geographic region and habitat type do not appear to play an obvious role in structuring host-microbe associations or feeding preferences. © 2018 John Wiley & Sons Ltd.

From Grouping to Coupling: A New Perceptual Organization in Vision, Psychology, and Biology

PubMed Central

Pinna, Baingio; Porcheddu, Daniele; Deiana, Katia

2016-01-01

In this work, perceptual organization has been studied with the same spirit and phenomenological methods used by Gestalt psychologists. This was accomplished through new conditions that cannot be explained in terms of the classical principles of grouping. Perceptual grouping represents the way through which our visual system builds integrated elements on the basis of the maximal homogeneity among the components of the stimulus pattern. Our results demonstrated the inconsistency of organization by grouping, and more importantly, the inconsistency of the principle of similarity. On the contrary, they suggested the unique role played by the principle of dissimilarity among elements that behaves like an accent or a visual emphasis within a whole. The principle of accentuation was here considered as imparting a directional structure to the elements and to the whole object thus creating new phenomena. The salience of the resulting phenomena reveals the supremacy of dissimilarity in relation to similarity and the fact that it belongs to a further organization dynamics that we called “coupling.” In biology, coupling and its principle of accentuation are very strongly related to disruptive camouflage. Moreover, they are source of sexual attraction. They advertise the presence and elicit species identification/communication. In human beings accentuation is needed to show ourselves to others, to understand the way we dress, choose, and create clothes or invent fashion, the way we change our body accentuating several parts and hiding some others, the way we use maquillage. The existence of maquillage itself is derived from the need to accentuate something with the purpose to increase sexual attraction, to exhibit physical strength and beauty, to show or hide social status (e.g., being the king, a warrior, a priest, etc.). Last but not least, accentuation plays a basic role also in making it easier or difficult to read and understand written words. PMID:27471483

From Grouping to Coupling: A New Perceptual Organization in Vision, Psychology, and Biology.

PubMed

Pinna, Baingio; Porcheddu, Daniele; Deiana, Katia

2016-01-01

In this work, perceptual organization has been studied with the same spirit and phenomenological methods used by Gestalt psychologists. This was accomplished through new conditions that cannot be explained in terms of the classical principles of grouping. Perceptual grouping represents the way through which our visual system builds integrated elements on the basis of the maximal homogeneity among the components of the stimulus pattern. Our results demonstrated the inconsistency of organization by grouping, and more importantly, the inconsistency of the principle of similarity. On the contrary, they suggested the unique role played by the principle of dissimilarity among elements that behaves like an accent or a visual emphasis within a whole. The principle of accentuation was here considered as imparting a directional structure to the elements and to the whole object thus creating new phenomena. The salience of the resulting phenomena reveals the supremacy of dissimilarity in relation to similarity and the fact that it belongs to a further organization dynamics that we called "coupling." In biology, coupling and its principle of accentuation are very strongly related to disruptive camouflage. Moreover, they are source of sexual attraction. They advertise the presence and elicit species identification/communication. In human beings accentuation is needed to show ourselves to others, to understand the way we dress, choose, and create clothes or invent fashion, the way we change our body accentuating several parts and hiding some others, the way we use maquillage. The existence of maquillage itself is derived from the need to accentuate something with the purpose to increase sexual attraction, to exhibit physical strength and beauty, to show or hide social status (e.g., being the king, a warrior, a priest, etc.). Last but not least, accentuation plays a basic role also in making it easier or difficult to read and understand written words.

Hyperalgesia and Persistent Pain after Breast Cancer Surgery: A Prospective Randomized Controlled Trial with Perioperative COX-2 Inhibition

PubMed Central

van Helmond, Noud; Steegers, Monique A.; Filippini-de Moor, Gertie P.; Vissers, Kris C.; Wilder-Smith, Oliver H.

2016-01-01

Background Persistent pain is a challenging clinical problem after breast cancer treatment. After surgery, inflammatory pain and nociceptive input from nerve injury induce central sensitization which may play a role in the genesis of persistent pain. Using quantitative sensory testing, we tested the hypothesis that adding COX-2 inhibition to standard treatment reduces hyperalgesia after breast cancer surgery. A secondary hypothesis was that patients developing persistent pain would exhibit more postoperative hyperalgesia. Methods 138 women scheduled for lumpectomy/mastectomy under general anesthesia with paravertebral block were randomized to COX-2 inhibition (2x40mg parecoxib on day of surgery, thereafter 2x200mg celecoxib/day until day five) or placebo. Preoperatively and 1, 5, 15 days and 1, 3, 6, 12 months postoperatively, we determined electric and pressure pain tolerance thresholds in dermatomes C6/T4/L1 and a 100mm VAS score for pain. We calculated the sum of pain tolerance thresholds and analyzed change in these versus preoperatively using mixed models analysis with factor medication. To assess hyperalgesia in persistent pain patients we performed an additional analysis on patients reporting VAS>30 at 12 months. Results 48 COX-2 inhibition and 46 placebo patients were analyzed in a modified intention to treat analysis. Contrary to our primary hypothesis, change in the sum of tolerance thresholds in the COX-2 inhibition group was not different versus placebo. COX-2 inhibition had an effect on pain on movement at postoperative day 5 (p<0.01). Consistent with our secondary hypothesis, change in sum of pressure pain tolerance thresholds in 11 patients that developed persistent pain was negative versus patients without pain (p<0.01) from day 5 to 1 year postoperatively. Conclusions Perioperative COX-2 inhibition has limited value in preventing sensitization and persistent pain after breast cancer surgery. Central sensitization may play a role in the genesis of persistent postsurgical pain. PMID:27935990

Deterministic assembly of land snail communities according to species size and diet.

PubMed

Schamp, Brandon; Horsák, Michal; Hájek, Michal

2010-07-01

1. We investigated whether coexisting snail species in 145 treeless fen communities in the Western Carpathian Mountains differed more in size and diet than would be expected by chance, as predicted for traits commonly associated with competition and differential resource acquisition under limiting similarity theory. 2. Contrary to expectations, coexisting snail species were no more different in body size than expected by chance under a null model. However, variation in body size played a significant role in structuring snail communities: coexisting snail species were significantly more similar with respect to body size. 3. We developed two new test statistics to expand our investigation of limiting similarity to include diet, a nominal trait. We tested whether communities of snails were characterized by a greater richness of diet, and whether different diets were represented more or less evenly within communities. Communities of snails were significantly less evenly distributed than expected by chance, with detritivores being over-represented relative to predatory strategies. 4. We also examined the effect of water pH and conductivity, herbaceous cover, and bryophyte and vascular plant richness, on these trends by examining how the effect size of our tests varied across these gradients. Convergence in species size increased with increasing habitat pH. Specifically, smaller snail species were over-represented in fen communities in general, and this effect was accentuated in increasingly calcareous fens. 5. Theory predicts that traits related strongly to environmental conditions are more likely to be convergent. Our findings support this suggestion, as small snail species have an advantage in tolerating freezing conditions over winter when refuges are limited. 6. These results add to the growing body of literature demonstrating that variation in body size and diet play a strong role in structuring communities, although frequently in ways not predicted by limiting similarity theory. Finally, our results increase our understanding of how species are assembled non-randomly into communities with respect to important traits.

Attributing Contributions of Climate Feedbacks to the Seasonal Cycle of Surface Warming due to CO2 Increase

NASA Astrophysics Data System (ADS)

Sejas, S.; Cai, M.

2012-12-01

Surfing warming due to CO2 doubling is a robust feature of coupled general circulation models (GCM), as noted in the IPCC AR4 assessment report. In this study, the contributions of different climate feedbacks to the magnitude, spatial distribution, and seasonality of the surface warming is examined using data from NCAR's CCSM4. In particular, a focus is placed on polar regions to see which feedbacks play a role in polar amplification and its seasonal pattern. A new climate feedback analysis method is used to isolate the surface warming or cooling contributions of both radiative and non-radiative (dynamical) climate feedbacks to the total (actual) surface temperature change given by the CCSM4. These contributions (or partial surface temperature changes) are additive and their total is approximately equal to the actual surface temperature change. What is found is that the effects of CO2 doubling alone warms the surface throughout with a maximum in polar regions, which indicates the CO2 forcing alone has a degree of polar warming amplification. Water vapor feedback is a positive feedback throughout but is most responsible for the surface warming found in the tropics. Polar warming amplification is found to be strongest away from summer (especially in NH), which is primarily caused by a positive feedback due to cloud feedbacks but with the surface temperature change due to the CO2 forcing alone and the ocean dynamics and storage feedback also playing an important role. Contrary to popular belief, surface albedo feedback (SAF) does not account for much of the polar amplification. SAF tries to amplify polar warming, but in summer. No major polar amplification is seen in summer for the actual surface temperature, so SAF is not the feedback responsible for polar amplification. This is actually a consequence of the ocean dynamics and storage feedback, which negates the effects of SAF to a large degree.

Dual-Located WHIRLY1 Interacting with LHCA1 Alters Photochemical Activities of Photosystem I and Is Involved in Light Adaptation in Arabidopsis

PubMed Central

Huang, Dongmei; Lin, Wenfang; Deng, Ban

2017-01-01

Plastid-nucleus-located WHIRLY1 protein plays a role in regulating leaf senescence and is believed to associate with the increase of reactive oxygen species delivered from redox state of the photosynthetic electron transport chain. In order to make sure whether WHIRLY1 plays a role in photosynthesis, in this study, the performances of photosynthesis were detected in Arabidopsis whirly1 knockout (kowhy1) and plastid localized WHIRLY1 overexpression (oepWHY1) plants. Loss of WHIRLY1 leads to a higher photochemical quantum yield of photosystem I Y(I) and electron transport rate (ETR) and a lower non-photochemical quenching (NPQ) involved in the thermal dissipation of excitation energy of chlorophyll fluorescence than the wild type. Further analyses showed that WHIRLY1 interacts with Light-harvesting protein complex I (LHCA1) and affects the expression of genes encoding photosystem I (PSI) and light harvest complexes (LHCI). Moreover, loss of WHIRLY1 decreases chloroplast NAD(P)H dehydrogenase-like complex (NDH) activity and the accumulation of NDH supercomplex. Several genes encoding the PSI-NDH complexes are also up-regulated in kowhy1 and the whirly1whirly3 double mutant (ko1/3) but steady in oepWHY1 plants. However, under high light conditions (800 μmol m−2 s−1), both kowhy1 and ko1/3 plants show lower ETR than wild-type which are contrary to that under normal light condition. Moreover, the expression of several PSI-NDH encoding genes and ERF109 which is related to jasmonate (JA) response varied in kowhy1 under different light conditions. These results indicate that WHIRLY1 is involved in the alteration of ETR by affecting the activities of PSI and supercomplex formation of PSI with LHCI or NDH and may acting as a communicator between the plastids and the nucleus. PMID:29112140

Implications of solar irradiance variability upon long-term changes in the Earth's atmospheric temperatures

NASA Technical Reports Server (NTRS)

Lee, Robert B., III

1992-01-01

From 1979 through 1987, it is believed that variability in the incoming solar energy played a significant role in changing the Earth's climate. Using high-precision spacecraft radiometric measurements, the incoming total solar irradiance (total amount of solar power per unit area) and the Earth's mean, global atmospheric temperatures were found to vary in phase with each other. The observed irradiance and temperature changes appeared to be correlated with the 11-year cycle of solar magnetic activity. During the period from 1979 through 1985, both the irradiance and temperature decreased. From 1985 to 1987, they increased. The irradiance changed approximately 0.1 percent, while the temperature varied as much as 0.6 C. During the 1979-1987 period, the temperatures were forecasted to rise linearly because of the anthropogenic build-up of carbon dioxide and the hypothesized 'global warming', 'greenhouse effect', scenarios. Contrary to these scenarios, the temperatures were found to vary in a periodic manner in phase with the solar irradiance changes. The observed correlations between irradiance and temperature variabilily suggest that the mean, global temperature of the Earth may decline between 1990 and 1997 as solar magnetic activity decreases.

Ectoparasites and fitness of female Columbian ground squirrels

PubMed Central

Raveh, Shirley; Neuhaus, Peter; Dobson, F. Stephen

2015-01-01

Parasites play an important role in the evolution of host traits via natural selection, coevolution and sexually selected ornaments used in mate choice. These evolutionary scenarios assume fitness costs for hosts. To test this assumption, we conducted an ectoparasite removal experiment in free-living Columbian ground squirrels (Urocittelus columbianus) in four populations over three years. Adult females were randomly chosen to be either experimentally treated with anti-parasite treatments (spot-on solution and flea powder, N = 61) or a sham treatment (control, N = 44). We expected that experimental females would show better body condition, increased reproductive success and enhanced survival. Contrary to our expectations, body mass was not significantly different between treatments at mating, birth of litter or weaning of young. Further, neither number nor size of young at weaning differed significantly between the two treatments. Survival to the next spring for adult females and juveniles was not significantly different between experimental and control treatments. Finally, annual fitness was not affected by the treatments. We concluded that females and their offspring were able compensate for the presence of ectoparasites, suggesting little or no fitness costs of parasites for females in the different colonies and during the years of our experiments. PMID:25870399

Neurotrophins, their receptors and KI-67 in human GH-secreting pituitary adenomas: an immunohistochemical analysis.

PubMed

Artico, M; Bianchi, E; Magliulo, G; De Vincentiis, M; De Santis, E; Orlandi, A; Santoro, A; Pastore, F S; Giangaspero, F; Caruso, R; Re, M; Fumagalli, L

2012-01-01

Pituitary adenomas are a diverse group of tumors arising from the pituitary gland. Typically, they are small, slow-growing, hormonally inactive lesions that come to light as incidental findings on radiologic or postmortem examinations, although some small, slow-growing lesions with excessive hormonal activity may manifest with a clinical syndrome. The family of neurotrophins plays a key role in the development and maintenance of the pituitary endocrine cell function and in the regulation of hypothalamo-pituitary-adrenocortical axis activity. The objective of our experimental study is to investigate the localization of the neurotrophins, their relative receptors and to detect the expression level of Ki-67 to determine whether all these factors participate in the transformation and development of human pituitary adenomas. A very strong expression of Neurotrophin-3 (NT-3) and its receptor TrKC was observed in the extracellular matrix (ECM) and vessel endothelium, together with a clear/marked presence of Brain-derived neurotrophic factor (BDNF), and its receptor TrKB, thus confirming their direct involvement in the progression of pituitary adenomas. On the contrary, NGF (Nerve growth factor) and its receptor TrKA and p75NTR were weakly expressed in the epithelial gland cells and the ECM.

Hippocampal lesions do not disrupt navigational map retention in homing pigeons under conditions when map acquisition is hippocampal dependent.

PubMed

Gagliardo, Anna; Ioalè, Paolo; Odetti, Francesca; Kahn, Meghan C; Bingman, Verner P

2004-08-12

In contrast to map-like navigation by familiar landmarks, understanding the relationship between the avian hippocampal formation (HF) and the homing pigeon navigational map has remained a challenge. With the goal of filling an empirical gap, we performed an experiment in which young homing pigeons learned a navigational map while being held in an outdoor aviary, and then half the birds were subjected to HF ablation. The question was whether HF lesion would impair retention of a navigational map learned under conditions known to require participation of HF. The pigeons, which had never flown from the aviary before, together with an additional control group that learned a navigational map with free-flight experience, were then released from two distant release sites. Contrary to expectation, the HF-lesioned birds oriented in a homeward direction in manner indistinguishable from the intact control pigeons raised in the same outdoor aviary. HF lesion did not result in a navigational map retention deficit. Together with previous results, it is now clear that regardless of the learning environment present during acquisition, HF plays no necessary role in the subsequent retention or operation of the homing pigeon navigational map.

The interplay between customer participation and difficulty of design examples in the online designing process and its effect on customer satisfaction: mediational analyses.

PubMed

Chang, Chia-Chi; Chen, Hui-Yun; Huang, I-Chiang

2009-04-01

In the current consumer-centric economy, consumers increasingly desire the opportunity to design their own products in order to express more effectively their self-image. Mass customization, based on efficient and flexible modulization designs, has provided individualized products to satisfy this desire. This work presents an experiment employed to demonstrate that customer participation leads to higher satisfaction. Specifically, the increment in customer satisfaction due to participation is greater when an easy example is provided than when either no example or a difficult one is provided. Additionally, self-congruity plays a mediating role on the customer participation-satisfaction relationship, and this mediating effect varies across different levels of the design example provided in the design process. When an easy design example is present, customer participation has a direct effect on satisfaction, in addition to the indirect effect of self-congruity. When a difficult example is provided, customer participation does not have incremental effects on either self-congruity or customer satisfaction. Finally, when no design example is shown to customers, contrary to our expectation, participation still enhances customer satisfaction due to an increased sense of self-congruity.

A Novel Angle Computation and Calibration Algorithm of Bio-Inspired Sky-Light Polarization Navigation Sensor

PubMed Central

Xian, Zhiwen; Hu, Xiaoping; Lian, Junxiang; Zhang, Lilian; Cao, Juliang; Wang, Yujie; Ma, Tao

2014-01-01

Navigation plays a vital role in our daily life. As traditional and commonly used navigation technologies, Inertial Navigation System (INS) and Global Navigation Satellite System (GNSS) can provide accurate location information, but suffer from the accumulative error of inertial sensors and cannot be used in a satellite denied environment. The remarkable navigation ability of animals shows that the pattern of the polarization sky can be used for navigation. A bio-inspired POLarization Navigation Sensor (POLNS) is constructed to detect the polarization of skylight. Contrary to the previous approach, we utilize all the outputs of POLNS to compute input polarization angle, based on Least Squares, which provides optimal angle estimation. In addition, a new sensor calibration algorithm is presented, in which the installation angle errors and sensor biases are taken into consideration. Derivation and implementation of our calibration algorithm are discussed in detail. To evaluate the performance of our algorithms, simulation and real data test are done to compare our algorithms with several exiting algorithms. Comparison results indicate that our algorithms are superior to the others and are more feasible and effective in practice. PMID:25225872

Activation patterns in superficial layers of neocortex change between experiences independent of behavior, environment, or the hippocampus.

PubMed

Takehara-Nishiuchi, Kaori; Insel, Nathan; Hoang, Lan T; Wagner, Zachary; Olson, Kathy; Chawla, Monica K; Burke, Sara N; Barnes, Carol A

2013-09-01

Previous work suggests that activation patterns of neurons in superficial layers of the neocortex are more sensitive to spatial context than activation patterns in deep cortical layers. A possible source of this laminar difference is the distribution of contextual information to the superficial cortical layers carried by hippocampal efferents that travel through the entorhinal cortex and subiculum. To evaluate the role that the hippocampus plays in determining context sensitivity in superficial cortical layers, behavior-induced expression of the immediate early gene Arc was examined in hippocampus-lesioned and control rats after exposing them to 2 distinct contexts. Contrary to expectations, hippocampal lesions had no observable effect on Arc expression in any neocortical layer relative to controls. Furthermore, another group of intact animals was exposed to the same environment twice, to determine the reliability of Arc-expression patterns across identical contextual and behavioral episodes. Although this condition included no difference in external input between 2 epochs, the significant layer differences in Arc expression still remained. Thus, laminar differences in activation or plasticity patterns are not likely to arise from hippocampal sources or differences in external inputs, but are more likely to be an intrinsic property of the neocortex.

Investment threshold and management reflection for industrial system cleaning: a case for China.

PubMed

Fang, Yiping

2012-03-01

The recognition that industrial activity plays an essential role in a sustainable society is now widespread. To understand the causal relationship between industrial pollution abatement expenditure and industrial system cleaning level in China is of considerable importance, especially under extremely rapid industrial growth and serious pressure of industrial pollutants abatement context. We use composite index assessment method and regression analysis in this paper. We establish the mathematical model between composite industrial cleaner index and investment intensity for industrial pollutants abatement, and analyze the effects of industrial pollutants treatment and discharge indicators on composite industrial cleaner index in China. Results show that: (1) There is significant nonlinear relationship between composite industrial cleaner index and investment intensity for industrial pollutants abatement. (2) From single indicator perspective, the effect of investment intensity on pollutants treatment indicators is positively, on the contrary, the effect of investment intensity on pollutants discharge indicators is negatively; (3) From decomposition cleaner index perspective, the effect of pollutants discharge level (process control) is higher than pollutants treatment capacity (end-of-pipe) on composite industrial cleaner index; (4) There is threshold between investment intensity and composite cleaner industrial index, it is a crucial reference scale for industrial environmental management in selected period.

Microfluidics and numerical simulation as methods for standardization of zebrafish sperm cell activation

PubMed Central

Scherr, Thomas; Knapp, Gerald L.; Guitreau, Amy; Park, Daniel Sang-Won; Tiersch, Terrence; Nandakumar, Krishnaswamy

2017-01-01

Sperm cell activation plays a critical role in a range of biological and engineering processes, from fertilization to cryopreservation protocol evaluation. Across a range of species, ionic and osmotic effects have been discovered that lead to activation. Sperm cells of zebrafish (Danio rerio) initiate motility in a hypoosmotic environment. In this study, we employ a microfluidic mixer for the purpose of rapidly diluting the extracellular medium to initiate the onset of cell motility. The use of a microchannel offers a rapid and reproducible mixing profile throughout the device. This greatly reduces variability from trial to trial relative to the current methods of analysis. Coupling these experiments with numerical simulations, we were able to investigate the dynamics of intracellular osmolality as each cell moves along its path through the micromixer. Our results suggest that intracellular osmolality, and hence intracellular ion concentration, only slightly decreases, contrary to the common thought that larger changes in these parameters are required for activation. Utilizing this framework, microfluidics for controlled extracellular environments and associated numerical modeling, has practical applicability in standardizing high-throughput aquatic sperm activation, and more fundamentally, investigations of the intracellular environment leading to motility. PMID:26026298

The expanding phenotype of mitochondrial myopathy.

PubMed

DiMauro, Salvatore; Gurgel-Giannetti, Juliana

2005-10-01

Our understanding of mitochondrial diseases (defined restrictively as defects in the mitochondrial respiratory chain) continues to progress apace. In this review we provide an update of information regarding disorders that predominantly or exclusively affect skeletal muscle. Most recently described mitochondrial myopathies are due to defects in nuclear DNA, including coenzyme Q10 deficiency, and mutations in genes that control mitochondrial DNA (mtDNA) abundance and structure such as POLG and TK2. Barth syndrome, an X-linked recessive mitochondrial myopathy/cardiopathy, is associated with altered lipid composition of the inner mitochondrial membrane, but a putative secondary impairment of the respiratory chain remains to be documented. Concerning the 'other genome', the role played by mutations in protein encoding genes of mtDNA in causing isolated myopathies has been confirmed. It has also been confirmed that mutations in tRNA genes of mtDNA can cause predominantly myopathic syndromes and - contrary to conventional wisdom - these mutations can be homoplasmic. Defects in the mitochondrial respiratory chain impair energy production and almost invariably involve skeletal muscle, causing exercise intolerance, myalgia, cramps, or fixed weakness, which often affects extraocular muscles and results in droopy eyelids (ptosis) and progressive external ophthalmoplegia.

Children’s Feedback Preferences in Response to an Experimentally Manipulated Peer Evaluation Outcome: The Role of Depressive Symptoms

PubMed Central

Dekovic, Maja; Vermande, Marjolijn; Telch, Michael J.

2007-01-01

The present study examined the linkage between pre-adolescent children’s depressive symptoms and their preferences for receiving positive vs. negative feedback subsequent to being faced with an experimentally manipulated peer evaluation outcome in real time. Participants (n = 142) ages 10 to 13, played a computer contest based on the television show Survivor and were randomized to either a peer rejection (i.e., receiving the lowest total ‘likeability’ score from a group of peer-judges), a peer success (i.e., receiving the highest score), or a control peer evaluation condition. Children’s self-reported feedback preferences were then assessed. Results revealed that participants assigned to the negative evaluation outcome, relative to either the success or the control outcome, showed a significantly higher subsequent preference for negatively tuned feedback. Contrary to previous work and predictions derived from self-verification theory, children higher in depressive symptoms were only more likely to prefer negative feedback in response to the negative peer evaluation outcome. These effects for depression were not accounted for by either state mood at baseline or mood change in response to the feedback manipulation. PMID:17279340

Molecular Dynamics Information Improves cis-Peptide-Based Function Annotation of Proteins.

PubMed

Das, Sreetama; Bhadra, Pratiti; Ramakumar, Suryanarayanarao; Pal, Debnath

2017-08-04

cis-Peptide bonds, whose occurrence in proteins is rare but evolutionarily conserved, are implicated to play an important role in protein function. This has led to their previous use in a homology-independent, fragment-match-based protein function annotation method. However, proteins are not static molecules; dynamics is integral to their activity. This is nicely epitomized by the geometric isomerization of cis-peptide to trans form for molecular activity. Hence we have incorporated both static (cis-peptide) and dynamics information to improve the prediction of protein molecular function. Our results show that cis-peptide information alone cannot detect functional matches in cases where cis-trans isomerization exists but 3D coordinates have been obtained for only the trans isomer or when the cis-peptide bond is incorrectly assigned as trans. On the contrary, use of dynamics information alone includes false-positive matches for cases where fragments with similar secondary structure show similar dynamics, but the proteins do not share a common function. Combining the two methods reduces errors while detecting the true matches, thereby enhancing the utility of our method in function annotation. A combined approach, therefore, opens up new avenues of improving existing automated function annotation methodologies.

A Cross-Cultural Study of Punishment Beliefs and Decisions.

PubMed

Zhang, Yanyan; Chen, Chuansheng; Greenberger, Ellen; Knowles, Eric D

2017-02-01

The current research examined cultural similarities and differences in punishment beliefs and decisions. Participants were European Americans ( N = 50), Chinese Americans ( N = 57), and Chinese in Mainland China ( N = 50). The Functions of Punishment Questionnaire was used to measure participants' beliefs about the retributive or deterrent functions of punishment and a scenario method was used to measure the extent to which punishment decisions were driven by individuals' concerns for retribution or deterrence. The results indicated that, contrary to the hypothesis that the retributive function would be emphasized by individualistic groups and the deterrent function by collectivistic groups, Mainland Chinese participants had a stronger belief in retribution and a weaker belief in deterrence than did European and Chinese Americans. The results also indicated that retribution played a bigger role in punishment decisions for Chinese than for the other two groups, but the importance of the deterrence function in punishment decisions did not differ across the three groups. Finally, the correlation between interdependence orientation and the belief in retribution was positive for Chinese but negative for European Americans. Taken together, the findings provided little evidence that collectivists are more deterrence-oriented and individualists more retribution-oriented.

Interaction of sea water and lava during submarine eruptions at mid-ocean ridges

USGS Publications Warehouse

Perfit, M.R.; Cann, J.R.; Fornari, D.J.; Engels, J.; Smith, D.K.; Ridley, W.I.; Edwards, M.H.

2003-01-01

Lava erupts into cold sea water on the ocean floor at mid-ocean ridges (at depths of 2,500 m and greater), and the resulting flows make up the upper part of the global oceanic crust. Interactions between heated sea water and molten basaltic lava could exert significant control on the dynamics of lava flows and on their chemistry. But it has been thought that heating sea water at pressures of several hundred bars cannot produce significant amounts of vapour and that a thick crust of chilled glass on the exterior of lava flows minimizes the interaction of lava with sea water. Here we present evidence to the contrary, and show that bubbles of vaporized sea water often rise through the base of lava flows and collect beneath the chilled upper crust. These bubbles of steam at magmatic temperatures may interact both chemically and physically with flowing lava, which could influence our understanding of deep-sea volcanic processes and oceanic crustal construction more generally. We infer that vapour formation plays an important role in creating the collapse features that characterize much of the upper oceanic crust and may accordingly contribute to the measured low seismic velocities in this layer.

Mind-body dualism and the biopsychosocial model of pain: what did Descartes really say?

PubMed

Duncan, G

2000-08-01

In the last two decades there have been many critics of western biomedicine's poor integration of social and psychological factors in questions of human health. Such critiques frequently begin with a rejection of Descartes' mind-body dualism, viewing this as the decisive philosophical moment, radically separating the two realms in both theory and practice. It is argued here, however, that many such readings of Descartes have been selective and misleading. Contrary to the assumptions of many recent authors, Descartes' dualism does attempt to explain the union of psyche and soma - with more depth than is often appreciated. Pain plays a key role in Cartesian as well as contemporary thinking about the problem of dualism. Theories of the psychological origins of pain symptoms persisted throughout the history of modern medicine and were not necessarily discouraged by Cartesian mental philosophy. Moreover, the recently developed biopsychosocial model of pain may have more in common with Cartesian dualism than it purports to have. This article presents a rereading of Descartes' mental philosophy and his views on pain. The intention is not to defend his theories, but to re-evaluate them and to ask in what respect contemporary theories represent any significant advance in philosophical terms.

No Change in Social Decision-Making Following Transcranial Direct Current Stimulation of the Right Temporoparietal Junction.

PubMed

Blair-West, Laura F; Hoy, Kate E; Hall, Phillip J; Fitzgerald, Paul B; Fitzgibbon, Bernadette M

2018-01-01

The right temporoparietal junction (rTPJ) is thought to play an important role in social cognition and pro-social decision-making. One way to explore this link is through the use of transcranial direct current stimulation (tDCS), a non-invasive brain stimulation method that is able to modulate cortical activity. The aim of this research was therefore to determine whether anodal tDCS to the rTPJ altered response to a social decision-making task. In this study, 34 healthy volunteers participated in a single-center, double-blinded, sham-controlled crossover design. Subjects received 20 min of active/sham anodal tDCS to the rTPJ before undertaking the Ultimatum Game (UG), a neuroeconomics paradigm in which participants are forced to choose between monetary reward and punishing an opponent's unfairness. Contrary to expectations, we found no significant difference between anodal and sham stimulation with regard to either the total number or reaction time of unfair offer rejections in the UG. This study draws attention to methodological issues in tDCS studies of the rTPJ, and highlights the complexity of social decision-making in the UG.

Photoprotection in sequestered plastids of sea slugs and respective algal sources

PubMed Central

Cruz, Sónia; Cartaxana, Paulo; Newcomer, Rebecca; Dionísio, Gisela; Calado, Ricardo; Serôdio, João; Pelletreau, Karen N.; Rumpho, Mary E.

2015-01-01

Some sea slugs are capable of retaining functional sequestered chloroplasts (kleptoplasts) for variable periods of time. The mechanisms supporting the maintenance of these organelles in animal hosts are still largely unknown. Non-photochemical quenching (NPQ) and the occurrence of a xanthophyll cycle were investigated in the sea slugs Elysia viridis and E. chlorotica using chlorophyll fluorescence measurements and pigment analysis. The photoprotective capacity of kleptoplasts was compared to that observed in their respective algal source, Codium tomentosum and Vaucheria litorea. A functional xanthophyll cycle and a rapidly reversible NPQ component were found in V. litorea and E. chlorotica but not in C. tomentosum and E. viridis. To our knowledge, this is the first report of the absence of a functional xanthophyll cycle in a green macroalgae. The absence of a functional xanthophyll cycle in C. tomentosum could contribute to the premature loss of photosynthetic activity and relatively short-term retention of kleptoplasts in E. viridis. On the contrary, E. chlorotica displays one of the longest functional examples of kleptoplasty known so far. We speculate that different efficiencies of photoprotection and repair mechanisms of algal food sources play a role in the longevity of photosynthetic activity in kleptoplasts retained by sea slugs. PMID:25601025

Cardiovascular Complications of Pregnancy

PubMed Central

Gongora, Maria Carolina; Wenger, Nanette K.

2015-01-01

Pregnancy causes significant metabolic and hemodynamic changes in a woman’s physiology to allow for fetal growth. The inability to adapt to these changes might result in the development of hypertensive disorders of pregnancy (hypertension, preeclampsia or eclampsia), gestational diabetes and preterm birth. Contrary to previous beliefs these complications are not limited to the pregnancy period and may leave permanent vascular and metabolic damage. There is in addition, a direct association between these disorders and increased risk of future cardiovascular disease (CVD, including hypertension, ischemic heart disease, heart failure and stroke) and diabetes mellitus. Despite abundant evidence of this association, women who present with these complications of pregnancy do not receive adequate postpartum follow up and counseling regarding their increased risk of future CVD. The postpartum period in these women represents a unique opportunity to intervene with lifestyle modifications designed to reduce the development of premature cardiovascular complications. In some cases it allows early diagnosis and treatment of chronic hypertension or diabetes mellitus. The awareness of this relationship is growing in the medical community, especially among obstetricians and primary care physicians, who play a pivotal role in detecting these complications and assuring appropriate follow up. PMID:26473833

Numerical assessment affects aggression and competitive ability: a team-fighting strategy for the ant Formica xerophila.

PubMed

Tanner, Colby J

2006-11-07

The relationship between numerical advantage and competitive ability is a fundamental component in contests between groups of social animals. An individual's ability to correctly assess the numerical state of its group is of vital importance. In addition to numerical dominance, the group's fighting ability also plays an important role in competitive interactions. By staging experimental fights between two Formica ant species, I show that Formica xerophila are able to assess their own group's strength prior to any competitive encounter. Ants that perceive themselves as part of a large group act more aggressively toward a competitor than ants that perceive themselves as isolated individuals. This increase in aggression improves F. xerophila's competitive ability. Furthermore, the number of individuals in a contest was found to affect competitive ability. In contests with equal number of competitors, groups of F. xerophila were more successful than individual F. xerophila. Contrary to previous predictions using Lanchester's laws of fighting, F. xerophila's ability to kill competitors increased nonlinearly with group size. This nonlinearity was due to the collective fighting strategy of an F. xerophila group isolating and engaging a single Formica integroides competitors.

Packaged water: optimizing local processes for sustainable water delivery in developing nations

PubMed Central

2011-01-01

With so much global attention and commitment towards making the Water and Sanitation targets of the Millennium Development Goals (MDGs) a reality, available figures seem to speak on the contrary as they reveal a large disparity between the expected and what currently obtains especially in developing countries. As studies have shown that the standard industrialized world model for delivery of safe drinking water technology may not be affordable in much of the developing world, packaged water is suggested as a low cost, readily available alternative water provision that could help bridge the gap. Despite the established roles that this drinking water source plays in developing nations, its importance is however significantly underestimated, and the source considered unimproved going by 'international standards'. Rather than simply disqualifying water from this source, focus should be on identifying means of improvement. The need for intervening global communities and developmental organizations to learn from and build on the local processes that already operate in the developing world is also emphasized. Identifying packaged water case studies of some developing nations, the implication of a tenacious focus on imported policies, standards and regulatory approaches on drinking water access for residents of the developing world is also discussed. PMID:21801391

The OmpL porin does not modulate redox potential in the periplasmic space of Escherichia coli.

PubMed

Sardesai, Abhijit A; Genevaux, Pierre; Schwager, Françoise; Ang, Debbie; Georgopoulos, Costa

2003-04-01

The Escherichia coli DsbA protein is the major oxidative catalyst in the periplasm. Dartigalongue et al. (EMBO J., 19, 5980-5988, 2000) reported that null mutations in the ompL gene of E.coli fully suppress all phenotypes associated with dsbA mutants, i.e. sensitivity to the reducing agent dithiothreitol (DTT) and the antibiotic benzylpenicillin, lack of motility, reduced alkaline phosphatase activity and mucoidy. They showed that OmpL is a porin and hypothesized that ompL null mutations exert their suppressive effect by preventing efflux of a putative oxidizing-reducing compound into the medium. We have repeated these experiments using two different ompL null alleles in at least three different E.coli K-12 genetic backgrounds and have failed to reproduce any of the ompL suppressive effects noted above. Also, we show that, contrary to earlier results, ompL null mutations alone do not result in partial DTT sensitivity or partial motility, nor do they appreciably affect bacterial growth rates or block propagation of the male-specific bacteriophage M13. Thus, our findings clearly demonstrate that ompL plays no perceptible role in modulating redox potential in the periplasm of E.coli.

First-principles study of alloying effects on fluorine incorporation in Al x Ga1-x N alloys

NASA Astrophysics Data System (ADS)

Wang, Rong; Tan, Wei; Zhang, Jian; Chen, Feng-Xiang; Wei, Su-Huai

2018-02-01

Incorporation of fluorine (F) into the AlGaN layer is crucial to the fabrication of enhancement-mode (E-mode) AlGaN/GaN high electron mobility transistors (HEMTs). However, the understanding of properties of F doping in AlGaN alloys is rather limited. Using first-principles calculations and the special quasirandom structure (SQS) approach, we investigate the alloying effects on the doping properties of F-incorporated Al x Ga1-x N alloys. We find that substitutional F on N sites (FN) and interstitial F (Fi) are dominant defects for F in Al x Ga1-x N alloys. For these two types of defects, both the global composition x and the local motif surrounding the dopant play important roles. On contrary, the incorporation of substitutional F on Ga sites (FGa) or Al sites (FAl) are affected only by the composition x. We also find that there exists a large asymmetric bowing for the effective formation energies of FN and Fi. These results are explained in terms of local structural distortion and electronic effects. The mechanism discussed in this paper can also be used in understanding doping in other semiconductor alloys.

Nonparallel linear stability analysis of unconfined vortices

NASA Astrophysics Data System (ADS)

Herrada, M. A.; Barrero, A.

2004-10-01

Parabolized stability equations [F. P. Bertolotti, Th. Herbert, and P. R. Spalart, J. Fluid. Mech. 242, 441 (1992)] have been used to study the stability of a family of swirling jets at high Reynolds numbers whose velocity and pressure fields decay far from the axis as rm-2 and r2(m-2), respectively [M. Pérez-Saborid, M. A. Herrada, A. Gómez-Barea, and A. Barrero, J. Fluid. Mech. 471, 51 (2002)]; r is the radial distance and m is a real number in the interval 0

Extinction risk and structure of a food web model

NASA Astrophysics Data System (ADS)

Pękalski, Andrzej; Szwabiński, Janusz; Bena, Ioana; Droz, Michel

2008-03-01

We investigate in detail the model of a trophic web proposed by Amaral and Meyer [Phys. Rev. Lett. 82, 652 (1999)]. We focus on small-size systems that are relevant for real biological food webs and for which the fluctuations play an important role. We show, using Monte Carlo simulations, that such webs can be nonviable, leading to extinction of all species in small and/or weakly coupled systems. Estimations of the extinction times and survival chances are also given. We show that before the extinction the fraction of highly connected species (“omnivores”) is increasing. Viable food webs exhibit a pyramidal structure, where the density of occupied niches is higher at lower trophic levels, and moreover the occupations of adjacent levels are closely correlated. We also demonstrate that the distribution of the lengths of food chains has an exponential character and changes weakly with the parameters of the model. On the contrary, the distribution of avalanche sizes of the extinct species depends strongly on the connectedness of the web. For rather loosely connected systems, we recover the power-law type of behavior with the same exponent as found in earlier studies, while for densely connected webs the distribution is not of a power-law type.

Entry one: striving for best practice in professional assessment.

PubMed

English, Justin M; Mykyta, Lu

2002-01-01

The aim of this study was to develop a best practice model of professional assessment to ensure efficient and effective delivery of home-based services to frail and disabled elders. In 2000, an innovative model of professional assessment was introduced by one of Australia's largest providers of home-based care in order to reduce multiple assessments and to reduce the utilisation of assessment as a gatekeeping tool for limiting access to services. Data was analysed from a random sample of 1500 clients drawn from a population of 5000 as well as through the use of a survey tool administered to the Organisation's assessment staff and other key stakeholders. Results revealed that, contrary to popular belief, carer advocacy plays a significant role in the professional assessment process to the point that clients with carers received significantly more services and service time that clients without such support. However, if not monitored, assessment can also be used as a gate-keeping tool as opposed to one that can provide significant benefits to the consumers through comprehensive need articulation. We argue that the "professional" approach does not preclude empowerment and that assessment should not be used as a gate-keeping tool.

N-arachidonoyl l-serine, an endocannabinoid-like brain constituent with vasodilatory properties

PubMed Central

Milman, Garry; Maor, Yehoshua; Abu-Lafi, Saleh; Horowitz, Michal; Gallily, Ruth; Batkai, Sandor; Mo, Fong-Ming; Offertaler, Laszlo; Pacher, Pal; Kunos, George; Mechoulam, Raphael

2006-01-01

The endocannabinoid N-arachidonoyl ethanolamine (anandamide), found both in the CNS and in the periphery, plays a role in numerous physiological systems. One might expect that the chemically related N-arachidonoyl-l-serine (ARA-S) could also be formed alongside anandamide. We have now isolated ARA-S from bovine brain and elucidated its structure by comparison with synthetic ARA-S. Contrary to anandamide, ARA-S binds very weakly to cannabinoid CB1 and CB2 or vanilloid TRPV1 (transient receptor potential vanilloid 1) receptors. However, it produces endothelium-dependent vasodilation of rat isolated mesenteric arteries and abdominal aorta and stimulates phosphorylation of p44/42 mitogen-activated protein (MAP) kinase and protein kinase B/Akt in cultured endothelial cells. ARA-S also suppresses LPS-induced formation of TNF-α in a murine macrophage cell line and in wild-type mice, as well as in mice deficient in CB1 or CB2 receptors. Many of these effects parallel those reported for abnormal cannabidiol (Abn-CBD), a synthetic agonist of a putative novel cannabinoid-type receptor. Hence, ARA-S may represent an endogenous agonist for this receptor. PMID:16467152

Cerebrospinal Fluid Amyloid-β 42, Total Tau and Phosphorylated Tau are Low in Patients with Normal Pressure Hydrocephalus: Analogies and Differences with Alzheimer's Disease.

PubMed

Santangelo, Roberto; Cecchetti, Giordano; Bernasconi, Maria Paola; Cardamone, Rosalinda; Barbieri, Alessandra; Pinto, Patrizia; Passerini, Gabriella; Scomazzoni, Francesco; Comi, Giancarlo; Magnani, Giuseppe

2017-01-01

Co-existence of Alzheimer's disease (AD) in normal pressure hydrocephalus (NPH) is a frequent finding, thus a common pathophysiological basis between AD and NPH has been postulated. We measured CSF amyloid-β 42 (Aβ42), total tau (t-tau), and phosphorylated tau (p-tau) concentrations in a sample of 294 patients with different types of dementia and 32 subjects without dementia. We then compared scores on neuropsychological tests of NPH patients with pathological and normal CSF Aβ42 values. Aβ42 levels were significantly lower in NPH than in control patients, with no significant differences between AD and NPH. On the contrary, t-tau and p-tau levels were significantly lower in NPH than in AD, with no differences between NPH and controls. NPH patients with pathological Aβ42 levels did not perform worse than NPH patients with normal Aβ42 levels in any cognitive domains. Our data seem to support the hypothesis of amyloid accumulation in brains of NPH patients. Nevertheless, amyloid does not seem to play a pathogenetic role in the development of cognitive deficits in NPH.

Supervised machine learning algorithms to diagnose stress for vehicle drivers based on physiological sensor signals.

PubMed

Barua, Shaibal; Begum, Shahina; Ahmed, Mobyen Uddin

2015-01-01

Machine learning algorithms play an important role in computer science research. Recent advancement in sensor data collection in clinical sciences lead to a complex, heterogeneous data processing, and analysis for patient diagnosis and prognosis. Diagnosis and treatment of patients based on manual analysis of these sensor data are difficult and time consuming. Therefore, development of Knowledge-based systems to support clinicians in decision-making is important. However, it is necessary to perform experimental work to compare performances of different machine learning methods to help to select appropriate method for a specific characteristic of data sets. This paper compares classification performance of three popular machine learning methods i.e., case-based reasoning, neutral networks and support vector machine to diagnose stress of vehicle drivers using finger temperature and heart rate variability. The experimental results show that case-based reasoning outperforms other two methods in terms of classification accuracy. Case-based reasoning has achieved 80% and 86% accuracy to classify stress using finger temperature and heart rate variability. On contrary, both neural network and support vector machine have achieved less than 80% accuracy by using both physiological signals.

Numerical assessment affects aggression and competitive ability: a team-fighting strategy for the ant Formica xerophila

PubMed Central

Tanner, Colby J

2006-01-01

The relationship between numerical advantage and competitive ability is a fundamental component in contests between groups of social animals. An individual's ability to correctly assess the numerical state of its group is of vital importance. In addition to numerical dominance, the group's fighting ability also plays an important role in competitive interactions. By staging experimental fights between two Formica ant species, I show that Formica xerophila are able to assess their own group's strength prior to any competitive encounter. Ants that perceive themselves as part of a large group act more aggressively toward a competitor than ants that perceive themselves as isolated individuals. This increase in aggression improves F. xerophila's competitive ability. Furthermore, the number of individuals in a contest was found to affect competitive ability. In contests with equal number of competitors, groups of F. xerophila were more successful than individual F. xerophila. Contrary to previous predictions using Lanchester's laws of fighting, F. xerophila's ability to kill competitors increased nonlinearly with group size. This nonlinearity was due to the collective fighting strategy of an F. xerophila group isolating and engaging a single Formica integroides competitors. PMID:17015327

Quality of drinking water and high incidence rate of esophageal cancer in Golestan province of Iran: a probable link.

PubMed

Keshavarzi, Behnam; Moore, Farid; Najmeddin, Ali; Rahmani, Farah; Malekzadeh, Ahad

2012-02-01

Golestan province in north Iran is known to be a high-risk area for esophageal cancer (EC). Of a long list of multiple risk factors, this study focuses on a possible link between the epidemiologic patterns of EC and the anomalous concentration of some ions and elements in the drinking water sources. A total of 183 samples from 45 villages covering a wide range of EC mortality rates are collected and analyzed. The results demonstrate that NO(3)(-), SO(4)(2-), Sb, and Sr exceed the recommended maximum concentration level (MCL) in drinking water. This is more prominent in the villages with high esophageal cancer mortality rate, suggesting a possible link between EC incidence and water quality. Se concentration in drinking water increases from low to the high EC areas, a finding contrary to the expected trend. It is concluded that Se deficiency does not play a major role in the etiology of EC in the Golestan province. The statistical results obtained from Mann-Whitney and Kruskal-Wallis tests along with cluster analysis are consistent with the observed trend of EC mortality rate in Golestan province. © Springer Science+Business Media B.V. 2011

Interplay of quasiparticle-vibration coupling and pairing correlations on β-decay half-lives

NASA Astrophysics Data System (ADS)

Niu, Y. F.; Niu, Z. M.; Colò, G.; Vigezzi, E.

2018-05-01

The nuclear β-decay half-lives of Ni and Sn isotopes, around the closed shell nuclei 78Ni and 132Sn, are investigated by computing the distribution of the Gamow-Teller strength using the Quasiparticle Random Phase Approximation (QRPA) with quasiparticle-vibration coupling (QPVC), based on ground-state properties obtained by Hartree-Fock-Bogoliubov (HFB) calculations. We employ the effective interaction SkM* and a zero-range effective pairing force. The half-lives are strongly reduced by including the QPVC. We study in detail the effects of isovector (IV) and isoscalar (IS) pairing. Increasing the IV strength tends to increase the lifetime for nuclei in the proximity of, but lighter than, the closed-shell ones in QRPA calculations, while the effect is significantly reduced by taking into account the QPVC. On the contrary, the IS pairing mainly plays a role for nuclei after the shell closure. Increasing its strength decreases the half-lives, and the effect at QRPA and QRPA+QPVC level is comparable. The effect of IS pairing is particularly pronounced in the case of the Sn isotopes, where it turns out to be instrumental to obtain good agreement with experimental data.

Three-dimensional splay fault geometry and implications for tsunami generation.

PubMed

Moore, G F; Bangs, N L; Taira, A; Kuramoto, S; Pangborn, E; Tobin, H J

2007-11-16

Megasplay faults, very long thrust faults that rise from the subduction plate boundary megathrust and intersect the sea floor at the landward edge of the accretionary prism, are thought to play a role in tsunami genesis. We imaged a megasplay thrust system along the Nankai Trough in three dimensions, which allowed us to map the splay fault geometry and its lateral continuity. The megasplay is continuous from the main plate interface fault upwards to the sea floor, where it cuts older thrust slices of the frontal accretionary prism. The thrust geometry and evidence of large-scale slumping of surficial sediments show that the fault is active and that the activity has evolved toward the landward direction with time, contrary to the usual seaward progression of accretionary thrusts. The megasplay fault has progressively steepened, substantially increasing the potential for vertical uplift of the sea floor with slip. We conclude that slip on the megasplay fault most likely contributed to generating devastating historic tsunamis, such as the 1944 moment magnitude 8.1 Tonankai event, and it is this geometry that makes this margin and others like it particularly prone to tsunami genesis.

Directed evolution of human T cell receptor CDR2 residues by phage display dramatically enhances affinity for cognate peptide-MHC without increasing apparent cross-reactivity

PubMed Central

Dunn, Steven M.; Rizkallah, Pierre J.; Baston, Emma; Mahon, Tara; Cameron, Brian; Moysey, Ruth; Gao, Feng; Sami, Malkit; Boulter, Jonathan; Li, Yi; Jakobsen, Bent K.

2006-01-01

The mammalian α/β T cell receptor (TCR) repertoire plays a pivotal role in adaptive immunity by recognizing short, processed, peptide antigens bound in the context of a highly diverse family of cell-surface major histocompatibility complexes (pMHCs). Despite the extensive TCR–MHC interaction surface, peptide-independent cross-reactivity of native TCRs is generally avoided through cell-mediated selection of molecules with low inherent affinity for MHC. Here we show that, contrary to expectations, the germ line-encoded complementarity determining regions (CDRs) of human TCRs, namely the CDR2s, which appear to contact only the MHC surface and not the bound peptide, can be engineered to yield soluble low nanomolar affinity ligands that retain a surprisingly high degree of specificity for the cognate pMHC target. Structural investigation of one such CDR2 mutant implicates shape complementarity of the mutant CDR2 contact interfaces as being a key determinant of the increased affinity. Our results suggest that manipulation of germ line CDR2 loops may provide a useful route to the production of high-affinity TCRs with therapeutic and diagnostic potential. PMID:16600963

The relation between lattice parameters and very low twinning stress in Ni50Mn25+x Ga25-x magnetic shape memory alloys

NASA Astrophysics Data System (ADS)

Straka, L.; Drahokoupil, J.; Pacherová, O.; Fabiánová, K.; Kopecký, V.; Seiner, H.; Hänninen, H.; Heczko, O.

2016-02-01

In search of the origins of the extraordinary low twinning stress of Ni-Mn-Ga 10M martensite, we studied the temperature induced changes in lattice parameters of Ni50Mn25+x Ga25-x (x = 2.7-3.9) single crystal samples and compared them with twinning stress dependences. The alloys exhibited transformation to five-layered (10M) martensite structure (cubic to monoclinic) between 297 to 328 K and exhibited the magnetic shape memory effect in martensite. The structural changes were monitored using x-ray diffraction in the temperature range 200-343 K. The 10M structure was approximated by monoclinic lattice, a = b > c, γ > 90° with the coordinates derived from the cubic unit cell of the parent L21 phase. The lattice parameters γ and c/a correlate well with the universal linear increase of twinning stress of type 1 twins with decreasing temperature. On the contrary, the twinning stress is not affected by differences between a and b and thus a/b twins seem to play no role in a - c twin boundary motion resulting in magnetically induced reorientation.

Stabilization of flux during dead-end ultra-low pressure ultrafiltration.

PubMed

Peter-Varbanets, Maryna; Hammes, Frederik; Vital, Marius; Pronk, Wouter

2010-06-01

Gravity driven ultrafiltration was operated in dead-end mode without any flushing or cleaning. In contrary to general expectations, the flux value stabilized after about one week of operation and remained constant during an extended period of time (several months). Different surface water types and diluted wastewater were used as feed water and, depending on the feed water composition, stable flux values were in the range of 4-10 L h(-1) m(-2). When sodium azide was added to the feed water to diminish the biological activity, no stabilization of flux occurred, indicating that biological processes play an important role in the flux stabilization process. Confocal laser scanning microscopy revealed the presence of a biofouling layer, of which the structure changed over time, leading to relatively heterogeneous structures. It is assumed that the stabilization of flux is related to the development of heterogeneous structures in the fouling layer, due to biological processes in the layer. The phenomenon of flux stabilization opens interesting possibilities for application, for instance in simple and low-cost ultrafiltration systems for decentralized drinking water treatment in developing and transition countries, independent of energy supply, chemicals, or complex process control. 2010 Elsevier Ltd. All rights reserved.

Brazilian healthcare in the context of austerity: private sector dominant, government sector failing.

PubMed

Costa, Nilson do Rosário

2017-04-01

This paper presents the arguments in favor of government intervention in financing and regulation of health in Brazil. It describes the organizational arrangement of the Brazilian health system, for the purpose of reflection on the austerity agenda proposed for the country. Based on the literature in health economics, it discusses the hypothesis that the health sector in Brazil functions under the dominance of the private sector. The categories employed for analysis are those of the national health spending figures. An international comparison of indicators of health expenses shows that Brazilian public spending is a low proportion of total spending on Brazilian health. Expenditure on individuals' health by out-of-pocket payments is high, and this works against equitability. The private health services sector plays a crucial role in provision, and financing. Contrary to the belief put forward by the austerity agenda, public expenditure cannot be constrained because the government has failed in adequate provision of services to the poor. This paper argues that, since the Constitution did not veto activity by the private sector segment of the market, those interests that have the greatest capacity to vocalize have been successful in imposing their preferences in the configuration of the sector.

Change in activity of serine palmitoyltransferase affects sensitivity to syringomycin E in yeast Saccharomyces cerevisiae.

PubMed

Toume, Moeko; Tani, Motohiro

2014-09-01

Syringomycin E is a cyclic lipodepsipeptide produced by strains of the plant bacterium Pseudomonas syringae pv. syringae. Genetic studies involving the yeast Saccharomyces cerevisiae have revealed that complex sphingolipids play important roles in the action of syringomycin E. Here, we found a novel mutation that confers resistance to syringomycin E on yeast; that is, a deletion mutant of ORM1 and ORM2, which encode negative regulators of serine palmitoyltransferase catalyzing the initial step of sphingolipid biosynthesis, exhibited resistance to syringomycin E. On the contrary, overexpression of Orm2 resulted in high sensitivity to the toxin. Moreover, overexpression of Lcb1 and Lcb2, catalytic subunits of serine palmitoyltransferase, causes resistance to the toxin, whereas partial repression of expression of Lcb1 had the opposite effect. Partial reduction of complex sphingolipids by repression of expression of Aur1, an inositol phosphorylceramide synthase, also resulted in high sensitivity to the toxin. These results suggested that an increase in sphingolipid biosynthesis caused by a change in the activity of serine palmitoyltransferase causes resistance to syringomycin E. © 2014 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.

No Evidence for Moral Reward and Punishment in an Anonymous Context.

PubMed

Clavien, Christine; Mersch, Danielle P; Chapuisat, Michel

2016-01-01

Human social interactions are regulated by moral norms that define individual obligations and rights. These norms are enforced by punishment of transgressors and reward of followers. Yet, the generality and strength of this drive to punish or reward is unclear, especially when people are not personally involved in the situation and when the actual impact of their sanction is only indirect, i.e., when it diminishes or promotes the social status of the punished or rewarded individual. In a real-life study, we investigated if people are inclined to anonymously punish or reward a person for her past deeds in a different social context. Participants from three socio-professional categories voted anonymously for early career violinists in an important violin competition. We found that participants did not punish an immoral violin candidate, nor did they reward another hyper-moral candidate. On the contrary, one socio-professional category sanctioned hyper-morality. Hence, salient moral information about past behavior did not elicit punishment or reward in an impersonal situation where the impact of the sanction was indirect. We conclude that contextual features play an important role in human motivation to enforce moral norms.

Game theory and reciprocity in some extensive form experimental games.

PubMed

McCabe, K A; Rassenti, S J; Smith, V L

1996-11-12

We examine decision making in two-person extensive form game trees using nine treatments that vary matching protocol, payoffs, and payoff information. Our objective is to establish replicable principles of cooperative versus noncooperative behavior that involve the use of signaling, reciprocity, and backward induction strategies, depending on the availability of dominated direct punishing strategies and the probability of repeated interaction with the same partner. Contrary to the predictions of game theory, we find substantial support for cooperation under complete information even in various single-play treatments.

Role-playing for more realistic technical skills training.

PubMed

Nikendei, C; Zeuch, A; Dieckmann, P; Roth, C; Schäfer, S; Völkl, M; Schellberg, D; Herzog, W; Jünger, J

2005-03-01

Clinical skills are an important and necessary part of clinical competence. Simulation plays an important role in many fields of medical education. Although role-playing is common in communication training, there are no reports about the use of student role-plays in the training of technical clinical skills. This article describes an educational intervention with analysis of pre- and post-intervention self-selected student survey evaluations. After one term of skills training, a thorough evaluation showed that the skills-lab training did not seem very realistic nor was it very demanding for trainees. To create a more realistic training situation and to enhance students' involvement, case studies and role-plays with defined roles for students (i.e. intern, senior consultant) were introduced into half of the sessions. Results of the evaluation in the second term showed that sessions with role-playing were rated significantly higher than sessions without role-playing.

"Prey Play": Learning about Predators and Prey through an Interactive, Role-Play Game

ERIC Educational Resources Information Center

Deaton, Cynthia C. M.; Dodd, Kristen; Drennon, Katherine; Nagle, Jack

2012-01-01

"Prey Play" is an interactive role-play activity that provides fifth-grade students with opportunities to examine predator-prey interactions. This four-part, role-play activity allows students to take on the role of a predator and prey as they reflect on the behaviors animals exhibit as they collect food and interact with one another, as well as…

Phylogeny of the beaked whale genus Mesoplodon (Ziphiidae: Cetacea) revealed by nuclear introns: implications for the evolution of male tusks.

PubMed

Dalebout, Merel L; Steel, Debbie; Baker, C Scott

2008-12-01

With 14 species currently recognized, the beaked whale genus Mesoplodon (family Ziphiidae) is the most speciose in the order Cetacea. Beaked whales are widely distributed but are rarely seen at sea due to their oceanic distribution, deep-diving capacity, and apparent low abundance. Morphological differentiation among Mesoplodon species is relatively limited, with the exception of tooth form in adult males. Based on scarring patterns, males appear to use their tusk-like teeth as weapons in aggressive encounters with other males. Females are effectively toothless. We used sequences from seven nuclear introns (3348 base pairs) to construct a robust and highly resolved phylogeny, which was then used as a framework to test predictions from four hypotheses seeking to explain patterns of Mesoplodon tusk morphology and/or the processes that have driven the diversification of this genus: (1) linear progression of tusk form; (2) allopatric speciation through isolation in adjacent deep-sea canyons; (3) sympatric speciation through sexual selection on tusks; and (4) selection for species-recognition cues. Maximum-likelihood and Bayesian reconstructions confirmed the monophyly of the genus and revealed that what were considered ancestral and derived tusk forms have in fact arisen independently on several occasions, contrary to predictions from the linear-progression hypothesis. Further, none of the three well-supported species clades was confined to a single ocean basin, as might have been expected from the deep-sea canyon-isolation or sexual-selection hypotheses, and some species with similar tusks have overlapping distributions, contrary to predictions from the species-recognition hypothesis. However, the divergent tusk forms and sympatric distributions of three of the four sister-species pairs identified suggest that sexual selection on male tusks has likely played an important role in this unique radiation, although other forces are clearly also involved. To our knowledge, this is the first time that sexual selection has been explicitly implicated in the radiation of a mammalian group outside terrestrial ungulates.

Triiodothyronine regulates cell growth and survival in renal cell cancer.

PubMed

Czarnecka, Anna M; Matak, Damian; Szymanski, Lukasz; Czarnecka, Karolina H; Lewicki, Slawomir; Zdanowski, Robert; Brzezianska-Lasota, Ewa; Szczylik, Cezary

2016-10-01

Triiodothyronine plays an important role in the regulation of kidney cell growth, differentiation and metabolism. Patients with renal cell cancer who develop hypothyreosis during tyrosine kinase inhibitor (TKI) treatment have statistically longer survival. In this study, we developed cell based model of triiodothyronine (T3) analysis in RCC and we show the different effects of T3 on renal cell cancer (RCC) cell growth response and expression of the thyroid hormone receptor in human renal cell cancer cell lines from primary and metastatic tumors along with human kidney cancer stem cells. Wild-type thyroid hormone receptor is ubiquitously expressed in human renal cancer cell lines, but normalized against healthy renal proximal tube cell expression its level is upregulated in Caki-2, RCC6, SKRC-42, SKRC-45 cell lines. On the contrary the mRNA level in the 769-P, ACHN, HKCSC, and HEK293 cells is significantly decreased. The TRβ protein was abundant in the cytoplasm of the 786-O, Caki-2, RCC6, and SKRC-45 cells and in the nucleus of SKRC-42, ACHN, 769-P and cancer stem cells. T3 has promoting effect on the cell proliferation of HKCSC, Caki-2, ASE, ACHN, SK-RC-42, SMKT-R2, Caki-1, 786-0, and SK-RC-45 cells. Tyrosine kinase inhibitor, sunitinib, directly inhibits proliferation of RCC cells, while thyroid hormone receptor antagonist 1-850 (CAS 251310‑57-3) has less significant inhibitory impact. T3 stimulation does not abrogate inhibitory effect of sunitinib. Renal cancer tumor cells hypostimulated with T3 may be more responsive to tyrosine kinase inhibition. Moreover, some tumors may be considered as T3-independent and present aggressive phenotype with thyroid hormone receptor activated independently from the ligand. On the contrary proliferation induced by deregulated VHL and or c-Met pathways may transgress normal T3 mediated regulation of the cell cycle.

Adiponectin is not associated with renal function decline in community-dwelling elderly adults.

PubMed

Kobayashi, Hiroki; Otsuka, Hiromasa; Yanai, Mitsuru; Haketa, Akira; Hara, Motohiko; Hishiki, Mikano; Abe, Masanori; Soma, Masayoshi

2018-05-01

Adiponectin secreted by adipocytes plays an important role in the regulation of glucose and fatty acid metabolism. Contrary to findings in patients with chronic kidney disease (CKD), no prospective data about the association of serum adiponectin with renal function decline in the general population have yet appeared. Our objective was to analyze the relationship of total and high molecular weight (HMW) adiponectin with renal function decline as measured by cystatin C in community-dwelling elderly adults without moderate or severe CKD.In a prospective observational analysis, a total of 216 healthy elderly volunteers with eGFRcys ≥60 mL/min/1.73 m underwent anthropometric and laboratory tests at baseline and at follow-up visits. A subgroup with serum samples collected 5 years apart was further analyzed.There were no differences in either total or HMW adiponectin level between subjects subsequently undergoing rapid renal function decline and subjects with normal physiologic renal function decline (P = .71, P = .81). On univariate linear regression, neither total nor HMW adiponectin were associated with annual renal function decline (β = -0.23; P = .71, β = -0.057; P = .90). Multivariate analysis did not show a significant contribution of either total or HMW adiponectin to annual renal function decline (β = -0.50; P = .46, β = 0.01; P = .98). In the logistic regression analysis, we did not observe any statistically significant association of serum adiponectin levels with rapid renal function decline or incidence of CKD.Contrary to findings in populations with CKD, neither total nor HMW adiponectin had a substantial association with renal function decline in an elderly population with eGFRcys ≥60 mL/min/1.73 m. Our results and conclusions should not be extrapolated to subjects with other characteristics.

Gender Microaggressions and Learning Environments: The Role of Physical Space in Teaching Pedagogy and Communication

ERIC Educational Resources Information Center

Lester, Jaime; Yamanaka, Aoi; Struthers, Brice

2016-01-01

Career and technical education (CTE) programs account for a large proportion of student enrollments in community colleges each year. While women tend to dominate CTE enrollments overall, they remain concentrated in historically feminized fields contrary to nontraditional occupations in which less than 25% of workers are females. Drawing on the…

Does Maintenance of Colour Categories Rely on Language? Evidence to the Contrary from a Case of Semantic Dementia

ERIC Educational Resources Information Center

Haslam, C.; Wills, A. J.; Haslam, S. A.; Kay, J.; Baron, R.; McNab, F.

2007-01-01

Recent neuropsychological evidence, supporting a strong version of Whorfian principles of linguistic relativity, has reinvigorated debate about the role of language in colour categorisation. This paper questions the methodology used in this research and uses a novel approach to examine the unique contribution of language to categorisation…

Stressful Demands or Helpful Guidance? The Role of Display Rules in Indian Call Centers

ERIC Educational Resources Information Center

Little, Laura M.; Nelson, Debra L.; Quade, Matthew J.; Ward, Andrew

2011-01-01

This paper utilizes conservation of resources (COR) theory and two of Hofstede's (1980) dimensions of culture (individualism and power distance) to examine the impact of display rules on job satisfaction and performance in an Indian call center sample. Contrary to findings in an American sample (Wilk & Moynihan, 2005), we proposed that due to…

Using role play to develop cultural competence.

PubMed

Shearer, Ruth; Davidhizar, Ruth

2003-06-01

Role play is a useful teaching strategy for nursing education. This strategy can simulate patient behaviors, as well as demonstrate nursing interventions that students must learn to be clinically competent. Role play is a dramatic technique that encourages participation to improvise behaviors that may be encountered in nurse-patient situations. Using this technique, participants may test behaviors and decisions in an experimental atmosphere without risk of negative effects in a relationship. Role play is useful in developing cultural competence because participants may experience diverse roles. Cultural competence is the ability to care for patients in a culturally sensitive and appropriate manner. In role play, students may participate as culturally diverse patients or as nurses encountering patients from different cultures. Various teaching strategies facilitate successful use of role play in the classroom, including defining a time frame, selected roles, specific objectives, references, and grading criteria. To optimize learning, the importance of exploration and analysis must be emphasized. Many benefits and potential problems accompany use of role play.

"Reluctant Participants" in Role Play Simulations: Stage Fright or Bewilderment?

ERIC Educational Resources Information Center

Saunders, Danny

1985-01-01

Discusses factors contributing to participant reluctance in role playing--isolation of role play from the curriculum; lack of interest because of perceived irrelevance to social psychological themes; and acting anxiety. A two-step design which involves gradual role play introduction and observation by reluctant participants is suggested as a…

Mathematical Adventures in Role Play

ERIC Educational Resources Information Center

Tyce, Constance

2002-01-01

The provision of role play is vital in every early years setting. It provides opportunities for the development of all areas of learning. With careful thought and planning, all role play situations can provide children with mathematical adventures. Many examples of good quality role play had been observed in a variety of settings throughout…

Caring About Kids: The Importance of Play.

ERIC Educational Resources Information Center

National Inst. of Mental Health (DHHS), Rockville, MD. Div. of Scientific and Public Information.

In several brief sections, this pamphlet defines play, discusses how play helps a child develop, and how play changes as a child grows older, indicates the role of toys and certain play activities in promoting sex stereotypes, and identifies the role of fantasy and imagination in children's play. A discussion of the role of parents in fostering…

A Newly Identified Role of the Deciduous Forest Floor in the Timing of Green-Up

NASA Astrophysics Data System (ADS)

Lapenis, Andrei G.; Lawrence, Gregory B.; Buyantuev, Alexander; Jiang, Shiguo; Sullivan, Timothy J.; McDonnell, Todd C.; Bailey, Scott

2017-11-01

Plant phenology studies rarely consider controlling factors other than air temperature. We evaluate here the potential significance of physical and chemical properties of soil (edaphic factors) as additional important controls on phenology. More specifically, we investigate causal connections between satellite-observed green-up dates of small forest watersheds and soil properties in the Adirondack Mountains of New York, USA. Contrary to the findings of previous studies, where edaphic controls of spring phenology were found to be marginal, our analyses show that at least three factors manifest themselves as significant controls of seasonal patterns of variation in vegetated land surfaces observed from remote sensing: (1) thickness of the forest floor, (2) concentration of exchangeable soil potassium, and (3) soil acidity. For example, a thick forest floor appears to delay the onset of green-up. Watersheds with elevated concentrations of potassium are associated with early surface greening. We also found that trees growing in strongly acidified watersheds demonstrate delayed green-up dates. Overall, our work demonstrates that, at the scale of small forest watersheds, edaphic factors can explain a significant percentage of the observed spatial variation in land surface phenology that is comparable to the percentage that can be explained by climatic and landscape factors. We conclude that physical and chemical properties of forest soil play important roles in forest ecosystems as modulators of climatic drivers controlling the rate of spring soil warming and the transition of trees out of winter dormancy.

How Nectar-Feeding Bats Localize their Food: Echolocation Behavior of Leptonycteris yerbabuenae Approaching Cactus Flowers

PubMed Central

Koblitz, Jens C.; Fleming, Theodore H.; Medellín, Rodrigo A.; Kalko, Elisabeth K. V.; Schnitzler, Hans-Ulrich; Tschapka, Marco

2016-01-01

Nectar-feeding bats show morphological, physiological, and behavioral adaptations for feeding on nectar. How they find and localize flowers is still poorly understood. While scent cues alone allow no precise localization of a floral target, the spatial properties of flower echoes are very precise and could play a major role, particularly at close range. The aim of this study is to understand the role of echolocation for classification and localization of flowers. We compared the approach behavior of Leptonycteris yerbabuenae to flowers of a columnar cactus, Pachycereus pringlei, to that to an acrylic hollow hemisphere that is acoustically conspicuous to bats, but has different acoustic properties and, contrary to the cactus flower, present no scent. For recording the flight and echolocation behaviour we used two infrared video cameras under stroboscopic illumination synchronized with ultrasound recordings. During search flights all individuals identified both targets as a possible food source and initiated an approach flight; however, they visited only the cactus flower. In experiments with the acrylic hemisphere bats aborted the approach at ca. 40–50 cm. In the last instant before the flower visit the bats emitted a long terminal group of 10–20 calls. This is the first report of this behaviour for a nectar-feeding bat. Our findings suggest that L. yerbabuenae use echolocation for classification and localization of cactus flowers and that the echo-acoustic characteristics of the flower guide the bats directly to the flower opening. PMID:27684373

Neotropical forest expansion during the last glacial period challenges refuge hypothesis.

PubMed

Leite, Yuri L R; Costa, Leonora P; Loss, Ana Carolina; Rocha, Rita G; Batalha-Filho, Henrique; Bastos, Alex C; Quaresma, Valéria S; Fagundes, Valéria; Paresque, Roberta; Passamani, Marcelo; Pardini, Renata

2016-01-26

The forest refuge hypothesis (FRH) has long been a paradigm for explaining the extreme biological diversity of tropical forests. According to this hypothesis, forest retraction and fragmentation during glacial periods would have promoted reproductive isolation and consequently speciation in forest patches (ecological refuges) surrounded by open habitats. The recent use of paleoclimatic models of species and habitat distributions revitalized the FRH, not by considering refuges as the main drivers of allopatric speciation, but instead by suggesting that high contemporary diversity is associated with historically stable forest areas. However, the role of the emerged continental shelf on the Atlantic Forest biodiversity hotspot of eastern South America during glacial periods has been ignored in the literature. Here, we combined results of species distribution models with coalescent simulations based on DNA sequences to explore the congruence between scenarios of forest dynamics through time and the genetic structure of mammal species cooccurring in the central region of the Atlantic Forest. Contrary to the FRH predictions, we found more fragmentation of suitable habitats during the last interglacial (LIG) and the present than in the last glacial maximum (LGM), probably due to topography. We also detected expansion of suitable climatic conditions onto the emerged continental shelf during the LGM, which would have allowed forests and forest-adapted species to expand. The interplay of sea level and land distribution must have been crucial in the biogeographic history of the Atlantic Forest, and forest refuges played only a minor role, if any, in this biodiversity hotspot during glacial periods.

Complexity of CNC transcription factors as revealed by gene targeting of the Nrf3 locus.

PubMed

Derjuga, Anna; Gourley, Tania S; Holm, Teresa M; Heng, Henry H Q; Shivdasani, Ramesh A; Ahmed, Rafi; Andrews, Nancy C; Blank, Volker

2004-04-01

Cap'n'collar (CNC) family basic leucine zipper transcription factors play crucial roles in the regulation of mammalian gene expression and development. To determine the in vivo function of the CNC protein Nrf3 (NF-E2-related factor 3), we generated mice deficient in this transcription factor. We performed targeted disruption of two Nrf3 exons coding for CNC homology, basic DNA-binding, and leucine zipper dimerization domains. Nrf3 null mice developed normally and revealed no obvious phenotypic differences compared to wild-type animals. Nrf3(-/-) mice were fertile, and gross anatomy as well as behavior appeared normal. The mice showed normal age progression and did not show any apparent additional phenotype during their life span. We observed no differences in various blood parameters and chemistry values. We infected wild-type and Nrf3(-/-) mice with acute lymphocytic choriomeningitis virus and found no differences in these animals with respect to their number of virus-specific CD8 and CD4 T cells as well as their B-lymphocyte response. To determine whether the mild phenotype of Nrf3 null animals is due to functional redundancy, we generated mice deficient in multiple CNC factors. Contrary to our expectations, an absence of Nrf3 does not seem to cause additional lethality in compound Nrf3(-/-)/Nrf2(-/-) and Nrf3(-/-)/p45(-/-) mice. We hypothesize that the role of Nrf3 in vivo may become apparent only after appropriate challenge to the mice.

Gender, Power, and Intimate Partner Violence: A Study on Couples From Rural Malawi

PubMed Central

Conroy, Amy A.

2013-01-01

Gender-based power imbalances are perhaps the most compelling underlying explanation for intimate partner violence (IPV) among women in sub-Saharan Africa. However, an overemphasis on female victimization results in an incomplete understanding of men’s experiences as victims and the broader dyadic context in which violence occurs. This study examines the role of three domains of relationship power (power resources, processes, and outcomes) on sexual and physical IPV victimization in a unique sample of 466 young couples from Malawi. Two power resources were studied, namely, income and education level. Power processes were captured with a measure of couple communication and collaboration called unity. Power outcomes included a measure of relationship dominance (male dominated or female-dominated/egalitarian). Multilevel logistic regression using the Actor Partner Interpersonal Model framework was used to test whether respondent and partner data were predictive of IPV. The findings show that unity and male dominance were salient power factors that influenced young people’s risk for sexual IPV. Unity had a stronger protective effect on sexual IPV for women than for men. Involvement in a male-dominated relationship increased the risk of sexual IPV for women, but decreased the risk for men. The findings also showed that education level and unity were protective against physical IPV for both men and women. Contrary to what was expected, partner data did not play a role in the respondent’s experience of IPV. The consistency of these findings with the literature, theory, and study limitations are discussed. PMID:24227592

Gender, power, and intimate partner violence: a study on couples from rural Malawi.

PubMed

Conroy, Amy A

2014-03-01

Gender-based power imbalances are perhaps the most compelling underlying explanation for intimate partner violence (IPV) among women in sub-Saharan Africa. However, an overemphasis on female victimization results in an incomplete understanding of men's experiences as victims and the broader dyadic context in which violence occurs. This study examines the role of three domains of relationship power (power resources, processes, and outcomes) on sexual and physical IPV victimization in a unique sample of 466 young couples from Malawi. Two power resources were studied, namely, income and education level. Power processes were captured with a measure of couple communication and collaboration called unity. Power outcomes included a measure of relationship dominance (male dominated or female-dominated/egalitarian). Multilevel logistic regression using the Actor Partner Interpersonal Model framework was used to test whether respondent and partner data were predictive of IPV. The findings show that unity and male dominance were salient power factors that influenced young people's risk for sexual IPV. Unity had a stronger protective effect on sexual IPV for women than for men. Involvement in a male-dominated relationship increased the risk of sexual IPV for women, but decreased the risk for men. The findings also showed that education level and unity were protective against physical IPV for both men and women. Contrary to what was expected, partner data did not play a role in the respondent's experience of IPV. The consistency of these findings with the literature, theory, and study limitations are discussed.

Nonequilibrium atmospheric secondary organic aerosol formation and growth

PubMed Central

Perraud, Véronique; Bruns, Emily A.; Ezell, Michael J.; Johnson, Stanley N.; Yu, Yong; Alexander, M. Lizabeth; Zelenyuk, Alla; Imre, Dan; Chang, Wayne L.; Dabdub, Donald; Pankow, James F.; Finlayson-Pitts, Barbara J.

2012-01-01

Airborne particles play critical roles in air quality, health effects, visibility, and climate. Secondary organic aerosols (SOA) formed from oxidation of organic gases such as α-pinene account for a significant portion of total airborne particle mass. Current atmospheric models typically incorporate the assumption that SOA mass is a liquid into which semivolatile organic compounds undergo instantaneous equilibrium partitioning to grow the particles into the size range important for light scattering and cloud condensation nuclei activity. We report studies of particles from the oxidation of α-pinene by ozone and NO3 radicals at room temperature. SOA is primarily formed from low-volatility ozonolysis products, with a small contribution from higher volatility organic nitrates from the NO3 reaction. Contrary to expectations, the particulate nitrate concentration is not consistent with equilibrium partitioning between the gas phase and a liquid particle. Rather the fraction of organic nitrates in the particles is only explained by irreversible, kinetically determined uptake of the nitrates on existing particles, with an uptake coefficient that is 1.6% of that for the ozonolysis products. If the nonequilibrium particle formation and growth observed in this atmospherically important system is a general phenomenon in the atmosphere, aerosol models may need to be reformulated. The reformulation of aerosol models could impact the predicted evolution of SOA in the atmosphere both outdoors and indoors, its role in heterogeneous chemistry, its projected impacts on air quality, visibility, and climate, and hence the development of reliable control strategies. PMID:22308444

Long-term effects of a universal family intervention: mediation through parent-adolescent conflict.

PubMed

Jensen, Michaeline R; Wong, Jessie J; Gonzales, Nancy A; Dumka, Larry E; Millsap, Roger; Coxe, Stefany

2014-01-01

This randomized trial of a family-focused preventive intervention for Mexican American middle schoolers examined internalizing, externalizing, and substance use outcomes in late adolescence, 5 years after completing the intervention. Parent-adolescent conflict was tested as a mediator of these effects. The role of parent and adolescent acculturation in these pathways was also examined. There were 494 seventh-grade adolescents and their primary female caregivers randomized to receive either a 9-week multicomponent intervention or a brief workshop control group. Assessments were conducted at pretest, 2-year follow-up (9th grade), and 5-year follow-up (when most participants were in the 12th grade). The Bridges program significantly reduced mother-adolescent conflict measured in the 9th grade, with conflict mediating program effects on internalizing and externalizing symptoms, adolescent substance use, and diagnosed internalizing disorder in late adolescence. Mother and child acculturation were both significantly predictive of late adolescence outcomes. Contrary to hypotheses, neither mother nor child acculturation emerged as a significant predictor of mother-adolescent conflict, and the interaction of mother and adolescent acculturation was similarly not related to mother-adolescent conflict. Intervention effects were largely consistent across different levels of acculturation. These findings provide support for the efficacy of family-focused intervention during early adolescence, both in reducing mental health problems and substance use in the long term and in impacting parent-adolescent conflict processes that appear to play an important role in the development of later adjustment problems.

Dnmt1 activity is dispensable in δ-cells but is essential for α-cell homeostasis.

PubMed

Damond, Nicolas; Thorel, Fabrizio; Kim, Seung K; Herrera, Pedro L

2017-07-01

In addition to β-cells, pancreatic islets contain α- and δ-cells, which respectively produce glucagon and somatostatin. The reprogramming of these two endocrine cell types into insulin producers, as observed after a massive β-cell ablation in mice, may help restoring a functional β-cell mass in type 1 diabetes. Yet, the spontaneous α-to-β and δ-to-β conversion processes are relatively inefficient in adult animals and the underlying epigenetic mechanisms remain unclear. Several studies indicate that the conserved chromatin modifiers DNA methyltransferase 1 (Dnmt1) and Enhancer of zeste homolog 2 (Ezh2) are important for pancreas development and restrict islet cell plasticity. Here, to investigate the role of these two enzymes in α- and δ-cell development and fate maintenance, we genetically inactivated them in each of these two cell types. We found that loss of Dnmt1 does not enhance the conversion of α- or δ-cells toward a β-like fate. In addition, while Dnmt1 was dispensable for the development of these two cell types, we noticed a gradual loss of α-, but not δ-cells in adult mice. Finally, we found that Ezh2 inactivation does not enhance α-cell plasticity, and, contrary to what is observed in β-cells, does not impair α-cell proliferation. Our results indicate that both Dnmt1 and Ezh2 play distinct roles in the different islet cell types. Copyright © 2017 Elsevier Ltd. All rights reserved.

The prevalence of human papilloma virus (HPV) infections in oral squamous cell carcinomas: a retrospective analysis of 88 patients and literature overview.

PubMed

Krüger, M; Pabst, A M; Walter, C; Sagheb, K; Günther, C; Blatt, S; Weise, K; Al-Nawas, B; Ziebart, T

2014-10-01

In addition to tobacco and alcohol consumption, the two main risk factors for oral squamous cell carcinoma (OSCC), recent studies have revealed infections with human papilloma virus (HPV) as an additional risk factor for OSCC development. In the field of head and neck malignancies, the prevalence of HPV infections in oropharyngeal cancer (OC) ranges in different studies up to 84%. While HPV infection is discussed as an independent risk factor in this region, its distinguished role in carcinogenesis of tumours localized to the oral cavity remains still uncertain. In this study, we analysed the HPV status in 88 consecutive patients with OSCCs localized anterior of the palatoglossal arch who were treated in the Department of Oral and Maxillofacial Surgery at the University Medical Center Mainz. The HPV status analysis was performed using DNA-PCR and immunostaining of p16 protein. The prevalence of HPV-positive OSCCs was about 6% (5 patients). In 3 patients the HPV subtypes 16/18 were found. No significant differences between the HPV positive and negative patients regarding age, gender, smoking and alcohol consumption, localization and TNM level could be detected. Contrary to other studies focussing on cancers of the lingual and palatine tonsil, the prevalence of HPV infections was much lower in the oral cavity. Therefore HPV infection might play a less important role in oral carcinogenesis. Copyright © 2014 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

FOOD ACQUISITION AND INTRA-HOUSEHOLD CONSUMPTION PATTERNS: A STUDY OF LOW AND MIDDLE INCOME URBAN HOUSEHOLDS IN DELHI, INDIA.

PubMed

Pradhan, Mr; Taylor, Fc; Agrawal, S; Prabhakaran, D; Ebrahim, S

2013-12-01

Food habits and choices in India are shifting due to many factors: changing food markets, fast urbanization, food price inflation, uncertain food production and unequal distribution during the past decade. This study aims to explore food acquisition and intra-household consumption patterns in urban low and middle income (LMI) households in Delhi. Twenty households were randomly selected from the Center for Cardio-metabolic Risk Reduction in South Asia (CARRS) surveillance study. Data were derived from 20 questionnaires administered to women responsible for food preparation, four key-informant-interviews, and 20 in-depth interviews with household heads during September-November 2011. STATA and ATLAS.ti software were used for data analysis. Half of the households spent at least two-thirds of their income on food. The major expenditures were on vegetables (22% of total food expenditure), milk and milk products (16%), and cereal and related products (15%). Income, food prices, food preferences, and seasonal variation influenced food expenditure. Adults usually ate two to three times a day while children ate more frequently. Eating sequence was based on the work pattern within the household and cultural beliefs. Contrary to previous evidence, there was no gender bias in intra-household food distribution. Women considered food acquisition, preparation and distribution part of their self-worth and played a major role in food related issues in the household. Women's key roles in food acquisition, preparation and intra household food consumption should be considered in formulating food policies and programs.

Insights into Brain Glycogen Metabolism

PubMed Central

Mathieu, Cécile; de la Sierra-Gallay, Ines Li; Duval, Romain; Xu, Ximing; Cocaign, Angélique; Léger, Thibaut; Woffendin, Gary; Camadro, Jean-Michel; Etchebest, Catherine; Haouz, Ahmed; Dupret, Jean-Marie; Rodrigues-Lima, Fernando

2016-01-01

Brain glycogen metabolism plays a critical role in major brain functions such as learning or memory consolidation. However, alteration of glycogen metabolism and glycogen accumulation in the brain contributes to neurodegeneration as observed in Lafora disease. Glycogen phosphorylase (GP), a key enzyme in glycogen metabolism, catalyzes the rate-limiting step of glycogen mobilization. Moreover, the allosteric regulation of the three GP isozymes (muscle, liver, and brain) by metabolites and phosphorylation, in response to hormonal signaling, fine-tunes glycogenolysis to fulfill energetic and metabolic requirements. Whereas the structures of muscle and liver GPs have been known for decades, the structure of brain GP (bGP) has remained elusive despite its critical role in brain glycogen metabolism. Here, we report the crystal structure of human bGP in complex with PEG 400 (2.5 Å) and in complex with its allosteric activator AMP (3.4 Å). These structures demonstrate that bGP has a closer structural relationship with muscle GP, which is also activated by AMP, contrary to liver GP, which is not. Importantly, despite the structural similarities between human bGP and the two other mammalian isozymes, the bGP structures reveal molecular features unique to the brain isozyme that provide a deeper understanding of the differences in the activation properties of these allosteric enzymes by the allosteric effector AMP. Overall, our study further supports that the distinct structural and regulatory properties of GP isozymes contribute to the different functions of muscle, liver, and brain glycogen. PMID:27402852

Youth's Initiations of Civic and Political Discussions in Class: Do Youth's Perceptions of Teachers' Behaviors Matter and Why?

PubMed

Bayram Özdemir, Sevgi; Stattin, Håkan; Özdemir, Metin

2016-11-01

Teachers are thought to play an important role in fostering youth civic engagement; however, the current literature is limited with regard to providing concrete suggestions as to what teachers can do to promote youth civic engagement and why teachers have an impact on youth. To address these limitations, we simultaneously tested three alternative explanations to identify the critical way(s) in which perceived teachers' behaviors might contribute to youth civic engagement in school. We also investigated the underlying processes that may explain why youth's perceptions of teachers' behaviors matter, by focusing on the mediating roles of young people's feelings about politics and their political efficacy beliefs. The sample included 7th (n = 876, M age  = 13.42, SD = .71; 51 % girls) and 10th grade students (n = 857, M age  = 16.62, SD = .71; 51 % girls) residing in Sweden. Among the different aspects of perceived teacher behaviors, only an engaged and inspiring teaching style fostered youth's initiations of civic and political discussions in class over time among both early and late adolescents. Moreover, youth's feelings about politics significantly mediated the effect of perceived teachers' behaviors on youth civic engagement in class. Contrary to our expectation, youth's political efficacy did not act as a mediator. The present study sheds light on what teachers can do to promote youth civic and political engagement in a school setting.

The Skin-Mucus Microbial Community of Farmed Atlantic Salmon (Salmo salar)

PubMed Central

Minniti, Giusi; Hagen, Live Heldal; Porcellato, Davide; Jørgensen, Sven Martin; Pope, Phillip B.; Vaaje-Kolstad, Gustav

2017-01-01

The skin of the teleost is a flexible and scaled structure that protects the fish toward the external environment. The outermost surface of the skin is coated with mucus, which is believed to be colonized by a diverse bacterial community (commensal and/or opportunistic). Little is known about such communities and their role in fish welfare. In aquaculture, fish seem to be more susceptible to pathogens compared to wild fish. Indeed common fish farming practices may play important roles in promoting their vulnerability, possibly by causing changes to their microbiomes. In the present study, 16S rRNA gene amplicon sequencing was employed to analyze the composition of the farmed Salmo salar skin-mucus microbiome before and after netting and transfer. The composition of the bacterial community present in the rearing water was also investigated in order to evaluate its correlation with the community present on the fish skin. Our results reveal variability of the skin-mucus microbiome among the biological replicates before fish handling. On the contrary, after fish handling, the skin-mucus community exhibited structural similarity among the biological replicates and significant changes were observed in the bacterial composition compared to the fish analyzed prior to netting and transfer. Limited correlation was revealed between the skin-mucus microbiome and the bacterial community present in the rearing water. Finally, analysis of skin-mucus bacterial biomasses indicated low abundance for some samples, highlighting the need of caution when interpreting community data due to the possible contamination of water-residing bacteria. PMID:29104567

On the impacts of traditional Chinese culture on organ donation.

PubMed

Cai, Yu

2013-04-01

This article examines the impact of traditional Chinese culture on organ donation from the perspective of Confucianism, Buddhism, and Taoism. In each of these cultural systems, it appears that there are some particular sayings or remarks that are often taken in modern Chinese society to be contrary to organ donation, especially cadaveric organ donation. However, this article argues that the central concerns of Buddhism, Confucianism, and Taoism are "great love," "ren," and "dao," which can be reasonably interpreted to support organ donation. The author understands that each cultural system, in order to play its cultural function, must have its central concerns as well as relevant ritual practices (li) that incarnate its religious and ethical commitments. That is, each plays a general cultural role, which influences organ donation in particular not merely through abstract or general ethical principles and teachings, but through a combination of ethical teachings and the forming of particular ritual practices. This article contends that the primary reason Chinese individuals fail to donate sufficient cadaveric organs for transplantation is not because particular remarks or sayings from each of these systems appear to conflict with donation. Neither is it that the central concerns of these systems cannot support cadaveric donation. Rather, it is that modern Chinese individuals have failed to develop and secure relevant ritual practices that support the central concerns of organ transplantation. The article concludes that in order to promote more donations, there is a need to form relevant ritual practices supporting organ donation in conformity with the central concerns of these cultural systems.

Representation of Cultural Role-Play for Training

NASA Technical Reports Server (NTRS)

Santarelli, Thomas; Pepe, Aaron; Rosenzweiz, Larry; Paulus, John; Yi, Ahn Na

2010-01-01

The Department of Defense (000) has successfully applied a number of methods for cultural familiarization training ranging from stand-up classroom training, to face-to-face live role-play, to so-called smart-cards. Recent interest has turned to the use of single and mUlti-player gaming technologies to augment these traditional methods of cultural familiarization. One such system, termed CulturePad, has been designed as a game-based role-play environment suitable for use in training and experimentation involving cultural roleplay scenarios. This paper describes the initial CulturePad effort focused on a literature review regarding the use of role-play for cultural training and a feasibility assessment of using a game-mediated environment for role-play. A small-scale pilot involving cultural experts was conducted to collect qualitative behavioral data comparing live role-play to game-mediated role-play in a multiplayer gaming engine.

Role-play for medical students learning about communication: Guidelines for maximising benefits

PubMed Central

Nestel, Debra; Tierney, Tanya

2007-01-01

Background Role-play is widely used as an educational method for learning about communication in medical education. Although educational theory provides a sound rationale for using this form of simulation, there is little published evidence for its effectiveness. Students' prior experiences of role-play may influence the way in which they engage in this method. This paper explores students' experiences with the aim of producing guidelines for maximising the benefits of role-play within this learning context. Methods First-year undergraduate medical students participated in a role-play session as part of their communication programme. Before and after the session, students completed questionnaires. In the pre-session questionnaire, students were asked about their experiences of role-play and asked to identify helpful and unhelpful elements. Immediately after the session, students answered similar questions in relation to the role-play activity they had just completed. Descriptive statistics were used to analyse quantitative data and qualitative data was thematically analysed. Results 284 students completed evaluation forms. Although 63 (22.2%) had prior unhelpful experiences, most students (n = 274; 96.5%) found this experience helpful. Summary findings were that students reported the key aspects of helpful role-play were opportunities for observation, rehearsal and discussion, realistic roles and alignment of roles with other aspects of the curriculum. Unhelpful aspects were those that evoked strong negative emotional responses and factors that contributed to a lack of realism. Conclusion Role-play was valued by students in the acquisition of communication skills even though some had prior unhelpful experiences. Guidelines for effective role-play include adequate preparation, alignment of roles and tasks with level of practice, structured feedback guidelines and acknowledgment of the importance of social interactions for learning. PMID:17335561

Role-play for medical students learning about communication: guidelines for maximising benefits.

PubMed

Nestel, Debra; Tierney, Tanya

2007-03-02

Role-play is widely used as an educational method for learning about communication in medical education. Although educational theory provides a sound rationale for using this form of simulation, there is little published evidence for its effectiveness. Students' prior experiences of role-play may influence the way in which they engage in this method. This paper explores students' experiences with the aim of producing guidelines for maximising the benefits of role-play within this learning context. First-year undergraduate medical students participated in a role-play session as part of their communication programme. Before and after the session, students completed questionnaires. In the pre-session questionnaire, students were asked about their experiences of role-play and asked to identify helpful and unhelpful elements. Immediately after the session, students answered similar questions in relation to the role-play activity they had just completed. Descriptive statistics were used to analyse quantitative data and qualitative data was thematically analysed. 284 students completed evaluation forms. Although 63 (22.2%) had prior unhelpful experiences, most students (n = 274; 96.5%) found this experience helpful. Summary findings were that students reported the key aspects of helpful role-play were opportunities for observation, rehearsal and discussion, realistic roles and alignment of roles with other aspects of the curriculum. Unhelpful aspects were those that evoked strong negative emotional responses and factors that contributed to a lack of realism. Role-play was valued by students in the acquisition of communication skills even though some had prior unhelpful experiences. Guidelines for effective role-play include adequate preparation, alignment of roles and tasks with level of practice, structured feedback guidelines and acknowledgment of the importance of social interactions for learning.

Using Role-Play for Expert Science Communication with Professional Stakeholders in Flood Risk Management

ERIC Educational Resources Information Center

McEwen, Lindsey; Stokes, Alison; Crowley, Kate; Roberts, Carolyn

2014-01-01

This paper explores role-play pedagogies in learning and communicating about cutting-edge flood science by flood risk management professionals in local government. It outlines role-play process/structure and evaluates participant perceptions of their learning experiences. Issues were impacts of prior role-play experience on attitudes brought to…

Cooperative learning with role play in Chinese pharmacology education.

PubMed

Wang, Jun; Hu, Xiamin; Xi, Jinglei

2012-03-01

Cooperative learning (CL) and role play are both efficient educational tools for enhancing Chinese student active learning and communication skills. This study was designed to obtain student feedback on the format of CL together with role play in the study of pharmacology in Chinese pharmaceutical undergraduates. CL was used in the self-study of new drugs used clinically but neglected in textbook and class teaching, so that groups of students were assigned to become "specialists" in one area of new drugs. Then, these "specialists" taught their new-found knowledge to other groups in role play approach involving an interaction between the pharmacist and a patient. Student perceptions of CL together with role play were examined using an eight-item survey instrument. Students were satisfied with CL together with role play. Majority of the students believed this teaching method enhanced their learning experience, made them gain more pharmacological expertise, increased the awareness of their career in future and self-educational abilities, and fostered their cooperation spirit and confidence. The materials on CL and role play were also believed pertinent. Only 63.4-76.5% and 63.1-37.3% of the students thought "CL and role-play were very funny" and "I felt very relaxed during CL together with role-play", respectively. CL together with role play is an efficient educational tool for enhancing student active-learning and communication skills. But Chinese students will take some time to adapt to this new teaching method.

The effect of presleep video-game playing on adolescent sleep.

PubMed

Weaver, Edward; Gradisar, Michael; Dohnt, Hayley; Lovato, Nicole; Douglas, Paul

2010-04-15

Video-game use before bedtime has been linked with poor sleep outcomes for adolescents; however, experimental evidence to support this link is sparse. The present study investigated the capacity of presleep video-game playing to extend sleep latency and reduce subjective feelings of sleepiness in adolescents. The arousing psychophysiologic mechanisms involved and the impact of presleep video-game playing on sleep architecture were also explored. Thirteen male adolescent "evening types" (mean age = 16.6 years, SD = 1.1) participated in a counterbalanced, within-subjects design with experimental (active video gaming) and control (passive DVD watching) conditions. The experiment was conducted in the Flinders University Sleep Research Laboratory. Relative to the control condition, presleep video-game playing increased sleep-onset latency (Z= 2.45, p= .01) and reduced subjective sleepiness (Z = 2.36, p = .02)-but only slightly. Video gaming was related to changes in cognitive alertness (as measured by a power: p < 0.01) but not physiologic arousal (as measured by heart rate: p > 0.05). Contrary to previous findings, sleep architecture was unaffected (both rapid eye movement and slow wave sleep: p > 0.05). Results suggest the direct effect of presleep video-game playing on adolescent sleep may be more modest than previously thought, suggesting that surveys linking stimulating presleep activities to poor sleep need substantiating with empirical evidence.

Dude Looks like a Lady: Gender Swapping in an Online Game

NASA Astrophysics Data System (ADS)

Huh, Searle; Williams, Dmitri

After reviewing the literature on online identity construction and developing a set of theory-based hypotheses, this chapter employs a novel combination of survey data and game-generated behavioral logs to examine gender swapping in EverQuest II. Gender swapping is defined as a difference between the gender reported by the player in the survey from the gender of the player's main character in the game. Motivations for play were measured using Yee's condensed MMO motivations scale, and behavioral logs supplied four main measures of gender-stereotypical in-game behaviors. Contrary to expectations, gender swapping was less common among female players, and swapping was rather rare in general. Homosexual players were more likely to change their online gender than straight players. Performance and socialization motivations for play did not differ significantly between swappers and nonswappers. Men who play female characters were not more likely to engage in stereotypically female acts than men who play male characters; however, women who played male characters did display a degree of hyper-masculine behavior. Some of these findings suggest that there may be less of the identity exploration or challenging of gender norms than some had expected, but the female population of players may be bimodal, composed of stereotypically female and male-leaning subgroups.

Centrality of women's multiple roles: beneficial and detrimental consequences for psychological well-being.

PubMed

Martire, L M; Stephens, M A; Townsend, A L

2000-03-01

Theorists have proposed that greater centrality (personal importance) of a social role is associated with better psychological well-being but that role centrality exacerbates the negative effects of stress in that same social role on well-being. The present study found evidence to support both hypotheses in a sample of 296 women who simultaneously occupied the roles of parent care provider, mother, wife, and employee. Greater centrality of all four roles was related to better psychological well-being. As predicted, wife centrality exacerbated the effects of wife stress on life satisfaction, and employee centrality exacerbated the effects of employee stress on depressive symptoms. Contrary to prediction, centrality of the mother role buffered women from the negative effects of mother stress on depressive symptoms. These findings point to an aspect of role identity that can benefit well-being but that has complex effects in the context of role stress.

High aspect ratio silicon nanowires control fibroblast adhesion and cytoskeleton organization

NASA Astrophysics Data System (ADS)

Andolfi, Laura; Murello, Anna; Cassese, Damiano; Ban, Jelena; Dal Zilio, Simone; Lazzarino, Marco

2017-04-01

Cell-cell and cell-matrix interactions are essential to the survival and proliferation of most cells, and are responsible for triggering a wide range of biochemical pathways. More recently, the biomechanical role of those interactions was highlighted, showing, for instance, that adhesion forces are essential for cytoskeleton organization. Silicon nanowires (Si NWs) with their small size, high aspect ratio and anisotropic mechanical response represent a useful model to investigate the forces involved in the adhesion processes and their role in cellular development. In this work we explored and quantified, by single cell force spectroscopy (SCFS), the interaction of mouse embryonic fibroblasts with a flexible forest of Si NWs. We observed that the cell adhesion forces are comparable to those found on collagen and bare glass coverslip, analogously the membrane tether extraction forces are similar to that on collagen but stronger than that on bare flat glass. Cell survival did not depend significantly on the substrate, although a reduced proliferation after 36 h was observed. On the contrary both cell morphology and cytoskeleton organization revealed striking differences. The cell morphology on Si-NW was characterized by a large number of filopodia and a significant decrease of the cell mobility. The cytoskeleton organization was characterized by the absence of actin fibers, which were instead dominant on collagen and flat glass support. Such findings suggest that the mechanical properties of disordered Si NWs, and in particular their strong asymmetry, play a major role in the adhesion, morphology and cytoskeleton organization processes. Indeed, while adhesion measurements by SCFS provide out-of-plane forces values consistent with those measured on conventional substrates, weaker in-plane forces hinder proper cytoskeleton organization and migration processes.

High aspect ratio silicon nanowires control fibroblast adhesion and cytoskeleton organization.

PubMed

Andolfi, Laura; Murello, Anna; Cassese, Damiano; Ban, Jelena; Dal Zilio, Simone; Lazzarino, Marco

2017-04-18

Cell-cell and cell-matrix interactions are essential to the survival and proliferation of most cells, and are responsible for triggering a wide range of biochemical pathways. More recently, the biomechanical role of those interactions was highlighted, showing, for instance, that adhesion forces are essential for cytoskeleton organization. Silicon nanowires (Si NWs) with their small size, high aspect ratio and anisotropic mechanical response represent a useful model to investigate the forces involved in the adhesion processes and their role in cellular development. In this work we explored and quantified, by single cell force spectroscopy (SCFS), the interaction of mouse embryonic fibroblasts with a flexible forest of Si NWs. We observed that the cell adhesion forces are comparable to those found on collagen and bare glass coverslip, analogously the membrane tether extraction forces are similar to that on collagen but stronger than that on bare flat glass. Cell survival did not depend significantly on the substrate, although a reduced proliferation after 36 h was observed. On the contrary both cell morphology and cytoskeleton organization revealed striking differences. The cell morphology on Si-NW was characterized by a large number of filopodia and a significant decrease of the cell mobility. The cytoskeleton organization was characterized by the absence of actin fibers, which were instead dominant on collagen and flat glass support. Such findings suggest that the mechanical properties of disordered Si NWs, and in particular their strong asymmetry, play a major role in the adhesion, morphology and cytoskeleton organization processes. Indeed, while adhesion measurements by SCFS provide out-of-plane forces values consistent with those measured on conventional substrates, weaker in-plane forces hinder proper cytoskeleton organization and migration processes.

Cooperation of NAD(P)H:quinone oxidoreductase 1 and UDP-glucuronosyltransferases reduces menadione cytotoxicity in HEK293 cells.

PubMed

Nishiyama, Takahito; Izawa, Tadashi; Usami, Mami; Ohnuma, Tomokazu; Ogura, Kenichiro; Hiratsuka, Akira

2010-04-09

Previous studies have shown that NAD(P)H:quinone oxidoreductase 1 (NQO1) plays an important role in the detoxification of menadione (2-methyl-1,4-naphthoquinone, also known as vitamin K3). However, menadiol (2-methyl-1,4-naphthalenediol) formed from menadione by NQO1-mediated reduction continues to be an unstable substance, which undergoes the reformation of menadione with concomitant formation of reactive oxygen species (ROS). Hence, we focused on the roles of phase II enzymes, with particular attention to UDP-glucuronosyltransferases (UGTs), in the detoxification process of menadione. In this study, we established an HEK293 cell line stably expressing NQO1 (HEK293/NQO1) and HEK293/NQO1 cell lines with doxycycline (DOX)-regulated expression of UGT1A6 (HEK293/NQO1/UGT1A6) and UGT1A10 (HEK293/NQO1/UGT1A10), and evaluated the role of NQO1 and UGTs against menadione-induced cytotoxicity. Our results differed from those of previous studies. HEK293/NQO1 was the most sensitive cell line to menadione cytotoxicity among cell lines established in this study. These phenomena were also observed in HEK293/NQO1/UGT1A6 and HEK293/NQO1/UGT1A10 cells in which the expression of UGT was suppressed by DOX treatment. On the contrary, HEK293/NQO1/UGT1A6 and HEK293/NQO1/UGT1A10 cells without DOX treatment were resistant to menadione-induced cytotoxicity. These results demonstrated that NQO1 is not a detoxification enzyme for menadione and that UGT-mediated glucuronidation of menadiol is the most important detoxification process. Copyright 2009 Elsevier Inc. All rights reserved.

Roles of survival and dispersal in reintroduction success of Griffon vulture (Gyps fulvus).

PubMed

Le Gouar, Pascaline; Robert, Alexandre; Choisy, Jean-Pierre; Henriquet, Sylvain; Lecuyer, Philippe; Tessier, Christian; Sarrazin, François

2008-06-01

The success of reintroduction programs greatly depends on the amount of mortality and dispersal of the released individuals. Although local environmental pressures are likely to play an important role in these processes, they have rarely been investigated because of the lack of spatial replicates of reintroduction. In the present study, we analyzed a 25-year data set encompassing 272 individuals released in five reintroduction programs of Griffon Vultures (Gyps fulvus) in France to examine the respective roles of survival and dispersal in program successes and failures. We use recent developments in multi-strata capture-recapture models to take into account tag loss in survival estimates and to consider and estimate dispersal among release areas. We also examined the effects of sex, age, time, area, and release status on survival, and we tested whether dispersal patterns among release areas were consistent with habitat selection theories. Results indicated that the survival of released adults was reduced during the first year after release, with no difference between sexes. Taking into account local observations only, we found that early survival rates varied across sites. However when we distinguished dispersal from mortality, early survival rates became equal across release sites. It thus appears that among reintroduction programs difference in failure and success was due to differential dispersal among release sites. We revealed asymmetrical patterns of dispersal due to conspecific attraction: dispersers selected the closest and the largest population. We showed that mortality can be homogeneous from one program to another while, on the contrary, dispersal is highly dependent on the matrix of established populations. Dispersal behavior is thus of major interest for metapopulation restoration and should be taken into account in planning reintroduction designs.

Differential roles of WNK4 in regulation of NCC in vivo.

PubMed

Yang, Yih-Sheng; Xie, Jian; Yang, Sung-Sen; Lin, Shih-Hua; Huang, Chou-Long

2018-05-01

The Na + -Cl - cotransporter (NCC) in distal convoluted tubule (DCT) plays important roles in renal NaCl reabsorption. The current hypothesis for the mechanism of regulation of NCC focuses on WNK4 and intracellular Cl - concentration ([Cl - ] i ). WNK kinases bind Cl - , and Cl - binding decreases the catalytic activity. It is believed that hypokalemia under low K + intake decreases [Cl - ] i to activate WNK4, which thereby phosphorylates and stimulates NCC through activation of SPAK. However, increased NCC activity and apical NaCl entry would mitigate the fall in [Cl - ] i. Whether [Cl - ] i in DCT under low-K + diet is sufficiently low to activate WNK4 is unknown. Furthermore, increased luminal NaCl delivery also stimulates NCC and causes upregulation of the transporter. Unlike low K + intake, increased luminal NaCl delivery would tend to increase [Cl - ] i . Thus we investigated the role of WNK4 and [Cl - ] i in regulating NCC. We generated Wnk4-knockout mice and examined regulation of NCC by low K + intake and by increased luminal NaCl delivery in knockout (KO) and wild-type mice. Wnk4-KO mice have marked reduction in the abundance, phosphorylation, and functional activity of NCC vs. wild type. Low K + intake increases NCC phosphorylation and functional activity in wild-type mice, but not in Wnk4-KO mice. Increased luminal NaCl delivery similarly upregulates NCC, which, contrary to low K + intake, is not abolished in Wnk4-KO mice. The results reveal that modulation of WNK4 activity by [Cl - ] i is not the sole mechanism for regulating NCC. Increased luminal NaCl delivery upregulates NCC via yet unknown mechanism(s) that may override inhibition of WNK4 by high [Cl - ] i .

The adoption of physical activity and eating behaviors among persons with obesity and in the general population: the role of implicit attitudes within the Theory of Planned Behavior.

PubMed

Chevance, Guillaume; Caudroit, Johan; Romain, Ahmed J; Boiché, Julie

2017-03-01

Obesity can be prevented by the combined adoption of a regular physical activity (PA) and healthy eating behaviors (EB). Researchers mainly focused on socio-cognitive models, such as the Theory of Planned Behavior (TPB), to identify the psychological antecedents of these behaviors. However, few studies were interested in testing the potential contribution of automatic processes in the prediction of PA and EB. Thus, the main objective of this study was to explore the specific role of implicit attitudes in the pattern of prediction of self-reported PA and EB in the TPB framework, among persons with obesity and in adults from the general population. One hundred and fifty-three adults participated to this cross-sectional study among which 59 obese persons (74% women, age: 50.6 ± 12.3 years, BMI: 36.8 ± 4.03 kg m - ²) and 94 people from the general population (51% women; age: 34.7 ± 8.9 years). Implicit attitudes toward PA and EB were estimated through two Implicit Association Tests. TPB variables, PA and EB were assessed by questionnaire. Regarding to the prediction of PA, a significant contribution of implicit attitudes emerged in obese people, β = .25; 95%[CI: .01, .50]; P = .044, beyond the TPB variables, contrary to participants from the general population. The present study suggests that implicit attitudes play a specific role among persons with obesity regarding PA. Other studies are needed to examine which kind of psychological processes are specifically associated with PA and EB among obese people.

Nociceptin/orphanin FQ antagonizes lipopolysaccharide-stimulated proliferation, migration and inflammatory signaling in human glioblastoma U87 cells.

PubMed

Bedini, Andrea; Baiula, Monica; Vincelli, Gabriele; Formaggio, Francesco; Lombardi, Sara; Caprini, Marco; Spampinato, Santi

2017-09-15

Glioblastoma is among the most aggressive brain tumors and has an exceedingly poor prognosis. Recently, the importance of the tumor microenvironment in glioblastoma cell growth and progression has been emphasized. Toll-like receptor 4 (TLR4) recognizes bacterial lipopolysaccharide (LPS) and endogenous ligands originating from dying cells or the extracellular matrix involved in host defense and in inflammation. G-protein coupled receptors (GPCRs) have gained interest in anti-tumor drug discovery due to the role that they directly or indirectly play by transactivating other receptors, causing cell migration and proliferation. A proteomic analysis showed that the nociceptin receptor (NOPr) is among the GPCRs significantly expressed in glioblastoma cells, including U87 cells. We describe a novel role of the peptide nociceptin (N/OFQ), the endogenous ligand of the NOPr that counteracts cell migration, proliferation and increase in IL-1β mRNA elicited by LPS via TLR4 in U87 glioblastoma cells. Signaling pathways through which N/OFQ inhibits LPS-mediated cell migration and elevation of [Ca 2+ ] i require β-arrestin 2 and are sensitive to TNFR-associated factor 6, c-Src and protein kinase C (PKC). LPS-induced cell proliferation and increase in IL-1β mRNA are counteracted by N/OFQ via β-arrestin 2, PKC and extracellular signal-regulated kinase 1/2; furthermore, the contributions of the transcription factors NF-kB and AP-1 were investigated. Independent of LPS, N/OFQ induces a significant increase in cell apoptosis. Contrary to what was observed in other cell models, a prolonged exposure to this endotoxin did not promote any tolerance of the cellular effects above described, including NOPr down-regulation while N/OFQ loses its inhibitory role. Copyright © 2017 Elsevier Inc. All rights reserved.

Validation of a Seven-Factor Structure for the Motives for Playing Drinking Games Measure.

PubMed

Zamboanga, Byron L; Audley, Shannon; Olthuis, Janine V; Blumenthal, Heidemarie; Tomaso, Cara C; Bui, Ngoc; Borsari, Brian

2017-04-01

Playing drinking games can be characterized as a high-risk drinking activity because games are typically designed to promote heavy alcohol consumption. While research suggests that young adults are motivated to play drinking games for a variety of reasons (e.g., for thrills/fun, for the competition), the Motives for Playing Drinking Games measure has received limited empirical attention. We examined the psychometric properties of this measure with a confirmation sample of young adults recruited from Amazon's MTurk ( N = 1,809, ages 18-25 years, 47% men; 41% not currently enrolled in college) and a validation sample of college students ( N = 671; ages 18-23 years; 26% men). Contrary to the 8-factor model obtained by Johnson and Sheets in a study published in 2004, examination of the factor structure with our confirmation sample yielded a revised 7-factor model that was invariant across race/ethnicity and college student status. This model was also validated with the college student sample. In the confirmation sample, enhancement/thrills and sexual pursuit motives for playing drinking games were positively associated with gaming frequency/consumption and negative gaming consequences. Furthermore, conformity motives for playing drinking games were positively associated with negative gaming consequences, while competition motives were positively associated with gaming frequency. These findings have significant implications for research and prevention/intervention efforts.

Understanding Positive Play: An Exploration of Playing Experiences and Responsible Gambling Practices.

PubMed

Wood, Richard T A; Griffiths, Mark D

2015-12-01

This study is one of the first to explore in detail the behaviors, attitudes and motivations of players that show no signs of at-risk or problem gambling behavior (so-called 'positive players'). Via an online survey, 1484 positive players were compared with 209 problem players identified using the Lie/Bet screen. The study identified two distinct groups of positive players defined according to their motivations to play and their engagement with responsible gambling (RG) practices. Those positive players that played most frequently employed the most personal RG strategies. Reasons that positive players gave for gambling were focused on leisure (e.g., playing for fun, being entertained, and/or winning a prize). By contrast, problem gamblers were much more focused upon modifying mood states (e.g., excitement, relaxation, depression and playing when bored or upset). The present study also suggests that online gambling is not, by default, inherently riskier than gambling in more traditional ways, as online gambling was the most popular media by which positive players gambled. Furthermore, most positive players reported that it was easier to stick to their limits when playing the National Lottery online compared to traditional retail purchasing of tickets. Problem players were significantly more likely than positive players to gamble with family and friends, suggesting that, contrary to a popular RG message, social play may not be inherently safer than gambling alone. It is proposed that players (generally) may identify more with the term 'positive play' than the term 'RG' which is frequently interpreted as being aimed at people with gambling problems, rather than all players.

Role-Playing Rhetoric of Science Pedagogy and the Study of Medical Ethics.

ERIC Educational Resources Information Center

Mitchell, Gordon

This essay blends practical reflection on current efforts to develop a role-playing curriculum at the University of Pittsburgh with a theoretical investigation of role-playing as a pedagogic technique. This paper examines educational literature on role-playing pedagogy as the topic is treated in a variety of academic fields including medicine,…

Role-Play and Student Engagement: Reflections from the Classroom

ERIC Educational Resources Information Center

Stevens, Rachel

2015-01-01

Role-play is viewed by scholars as an effective active learning strategy: it encourages participation among passive learners, adds dynamism to the classroom and promotes the retention of material. But what do students think of role-play? This study surveyed 144 students after a role-play activity in a history course and asked them to identify what…

"The Learning Sticks": Reflections on a Case Study of Role-Playing for Sustainability

ERIC Educational Resources Information Center

Gordon, Sue; Thomas, Ian

2018-01-01

Use of role-plays to develop deep student-learning has many advocates. Role-play is a powerful approach for learning that develops relevant skills in a range of disciplines and situations. In Higher Education, sustainability programmes role-play pedagogy appears to have great relevance for developing the competencies that these graduates will…

Assessing Women's Responses to Sexual Threat: Validity of a Virtual Role-Play Procedure

ERIC Educational Resources Information Center

Jouriles, Ernest N.; Rowe, Lorelei Simpson; McDonald, Renee; Platt, Cora G.; Gomez, Gabriella S.

2011-01-01

This study evaluated the validity of a role-play procedure that uses virtual reality technology to assess women's responses to sexual threat. Forty-eight female undergraduate students were randomly assigned to either a standard, face-to-face role-play (RP) or a virtual role-play (VRP) of a sexually coercive situation. A multimethod assessment…

Designing and Evaluating an Online Role Play in Conflict Management

ERIC Educational Resources Information Center

Hrastinski, Stefan; Watson, Jason

2009-01-01

Purpose: This paper aims to identify, through a literature review, key issues regarding how online role plays can be designed and to apply them when designing a role play on conflict management. Design/methodology/approach: By drawing on the key issues identified in the literature review, a role play on conflict management was designed and…

Teaching clinical interviewing skills using role-playing: conveying empathy to performing a suicide assessment: a primer for individual role-playing and scripted group role-playing.

PubMed

Shea, Shawn Christopher; Barney, Christine

2015-03-01

This article provides a useful introduction to the art of role-playing in both the individual format and the group format using scripted group role-playing (SGRP). Role-playing can provide powerful learning opportunities, but to do so it must be done well. This article imparts guidance toward this goal. SGRP may greatly enhance the acquisition of critical complex interviewing skills, such as suicide assessment and uncovering domestic violence, in health care providers across all disciplines, an educational goal that has not been achievable to date. Although research is at an early stage of development, the hope represented by SGRP is tangible. Copyright © 2015 Elsevier Inc. All rights reserved.

Children Are Ready to Learn, but Are We? The Role of Adult Relations in School Readiness

ERIC Educational Resources Information Center

Abo-Zena, Mona M.; New, Rebecca Staples

2012-01-01

Contrary to the concept of school readiness as achieving a particular set of attributes considered essential for educational success, this article is grounded in the assumption that all children are ready to learn, but what they are expected to learn varies widely from one cultural setting and historic period to another. The authors challenge the…

Shaping China’s Security Environment: The Role of the People’s Liberation Army

DTIC Science & Technology

2006-10-01

submarine officer) to argue to the contrary.23 In doing so, they criticized an earlier essay by Michael O’Hanlon, who had argued that in the most...David Hale and Lyric Hughes Hale, “China Takes Off,” Foreign Affairs, Vol. 82, No. 6, November-December 2003, pp. 26-53; and David Shambaugh, “China

Active Learning in the Classroom: The Use of Group Role Plays.

ERIC Educational Resources Information Center

Kitzerow, Phyllis

1990-01-01

Describes group role-playing activities that have been used to teach about education, criminology, and sex roles. Suggests that role play helps students to absorb and retain many of the insights about the issues involved. (DB)

[The development of European Union common research and development policy and programs with special regard to life sciences].

PubMed

Pörzse, Gábor

2009-08-09

Research and development (R&D) has been playing a leading role in the European Community's history since the very beginning of European integration. Its importance has grown in recent years, after the launch of the Lisbon strategy. Framework programs have always played a considerable part in community research. The aim of their introduction was to fine tune national R&D activities, and to successfully divide research tasks between the Community and the member states. The Community, from the very outset, has acknowledged the importance of life sciences. It is no coincidence that life sciences have become the second biggest priority in the last two framework programs. This study provides a historical, and at the same time analytical and evaluative review of community R&D policy and activity from the starting point of its development until the present day. It examines in detail how the changes in structure, conditional system, regulations and priorities of the framework programs have followed the formation of social and economic needs. The paper puts special emphasis on the analysis of the development of life science research, presenting how they have met the challenges of the age, and how they have been built into the framework programs. Another research area of the present study is to elaborate how successfully Hungarian researchers have been joining the community research, especially the framework programs in the field of life sciences. To answer these questions, it was essential to survey, process and analyze the data available in the national and European public and closed databases. Contrary to the previous documents, this analysis doesn't concentrate on the political and scientific background. It outlines which role community research has played in sustainable social and economic development and competitiveness, how it has supported common policies and how the processes of integration have been deepening. Besides, the present paper offers a complete review of the given field, from its foundation up until the present day, by elaborating the newest initiatives and ideas for the future. This work is also novel from the point of view of the given professional field, the life sciences in the framework programs, and processing and evaluating of data of Hungarian participation in the 5th and 6th framework programs in the field of life sciences.

Reality and Second-Language Role-Play.

ERIC Educational Resources Information Center

Piper, David; Piper, Terry

1983-01-01

Although role playing is a well-established and useful method of second language instruction, its success is often undermined by assignment of roles alien to the students' needs and experience. Redefinition of role playing to include the roles an individual assumes in everyday life will help the teacher plan more appropriate activities. (MSE)

Exploring the Impact of Role-Playing on Peer Feedback in an Online Case-Based Learning Activity

ERIC Educational Resources Information Center

Ching, Yu-Hui

2014-01-01

This study explored the impact of role-playing on the quality of peer feedback and learners' perception of this strategy in a case-based learning activity with VoiceThread in an online course. The findings revealed potential positive impact of role-playing on learners' generation of constructive feedback as role-playing was associated with higher…

A Case Study of an Online Role Play for Academic Staff.

ERIC Educational Resources Information Center

Bell, Maureen

Role play is a powerful technique for skills and attitude development. It is now possible to combine the advantages of face-to-face role play with the potential of the online environment. This paper reports on a case study of an asynchronous, anonymous, online role play conducted within a teaching course for academic staff. The following key…

Experiencing the Elicitation of User Requirements and Recording Them in Use Case Diagrams through Role-Play

ERIC Educational Resources Information Center

Costain, Gay; McKenna, Brad

2011-01-01

This paper describes a role-play exercise used in a second-year tertiary Systems Analysis and Design course, and the quantitative and qualitative analysis of the students' responses to a survey that solicited their perceptions of that role-play experience. The role-play involved students in eliciting user requirements from customers during a Joint…

Oh, Garbage! Decisions about Waste Disposal. Creative Role-Playing Exercises in Science and Technology Series.

ERIC Educational Resources Information Center

Parisi, Lynn; Pearson, Janice

This document is one of a series of role plays that focus on science-related social issues of concern in contemporary public policy formation. The role plays are designed to help students develop information-processing and decision making skills needed to deal effectively with such issues. The role plays guide students in analyzing science related…

Using and developing role plays in teaching aimed at preparing for social responsibility.

PubMed

Doorn, Neelke; Kroesen, J Otto

2013-12-01

In this paper, we discuss the use of role plays in ethics education for engineering students. After presenting a rough taxonomy of different objectives, we illustrate how role plays can be used to broaden students' perspectives. We do this on the basis of our experiences with a newly developed role play about a Dutch political controversy concerning pig transport. The role play is special in that the discussion is about setting up an institutional framework for responsible action that goes beyond individual action. In that sense, the role play serves a double purpose. It not only aims at teaching students to become aware of the different dimensions in decision making, it also encourages students to think about what such an institutional framework for responsible action might possibly look like.

Elucidating the role of recovery experiences in the job demands-resources model.

PubMed

Moreno-Jiménez, Bernardo; Rodríguez-Muñoz, Alfredo; Sanz-Vergel, Ana Isabel; Garrosa, Eva

2012-07-01

Based on the Job Demands-Resources (JD-R) model, the current study examined the moderating role of recovery experiences (i.e., psychological detachment from work, relaxation, mastery experiences, and control over leisure time) on the relationship between one job demand (i.e., role conflict) and work- and health-related outcomes. Results from our sample of 990 employees from Spain showed that psychological detachment from work and relaxation buffered the negative impact of role conflict on some of the proposed outcomes. Contrary to our expectations, we did not find significant results for mastery and control regarding moderating effects. Overall, findings suggest a differential pattern of the recovery experiences in the health impairment process proposed by the JD-R model.

Play Therapy: Role in Reading Improvement.

ERIC Educational Resources Information Center

Carmichael, Karla

1991-01-01

Reviews the literature concerning the role of play therapy (particularly sandplay and nondirected play therapy) in the improvement of reading. Suggests that the role of play therapy is to support the child, encourage the child, and build self-esteem thus creating the optimal learning environment for reading improvement. (RS)

Moderators of the relationship between masculinity and sexual prejudice in men: friendship, gender self-esteem, same-sex attraction, and religious fundamentalism.

PubMed

Mellinger, Christopher; Levant, Ronald F

2014-04-01

Masculinity has been found to predict the sexual prejudice of heterosexual men against gay men. The present study investigated the role of four variables as moderators of the relationships between two masculinity constructs (endorsement of traditional masculinity ideology and gender role conflict) and sexual prejudice in men. The hypothesized moderators were: direct and indirect friendships with gay men, gender self-esteem, acknowledged same-sex attraction, and religious fundamentalism. A total of 383 men completed 8 scales plus a demographic questionnaire. Direct friendship strengthened the positive relationship between masculinity ideology and sexual prejudice, contrary to hypothesis. This finding could mean that high masculinity ideology scores reduced the likelihood that a man with many gay friends would let go of his prejudice. Direct friendship did not moderate the relationship between gender role conflict and sexual prejudice nor did indirect friendship moderate either relationship; however, both forms of friendship predicted prejudice, as hypothesized. Gender self-esteem strengthened the positive relationships between both masculinity variables and sexual prejudice as hypothesized. Same-sex attraction weakened the relationship between gender role conflict and sexual prejudice as hypothesized, but contrary to hypothesis did not moderate the relationship between masculinity ideology and sexual prejudice. Religious fundamentalism predicted prejudice, but showed no significant moderation. The results were discussed in terms of limitations and suggestions for future research and application. In conclusion, this line of investigation appears promising and should be continued and the present findings can be utilized in anti-prejudice social marketing campaigns and in counseling.

Challenging gender stereotypes: resistance and exclusion.

PubMed

Mulvey, Kelly Lynn; Killen, Melanie

2015-01-01

The likelihood of resisting gender-stereotypic peer group norms, along with expectations about personal resistance, was investigated in 9- to 10-year-olds and 13- to 14-year-olds (N = 292). Participants were told about a stereotype conforming group (boys playing football; girls doing ballet) and a stereotype nonconforming group (boys doing ballet; girls playing football). Contrary to expectations from gender-stereotyping research, participants stated that they would personally resist gender-stereotypic norms, and more so than they would expect their peers to resist. However, expecting peers to resist declined with age. Participants expected that exclusion from the group was a consequence for challenging the peer group, and understood the asymmetrical status of gender stereotypes with an expectation that it would be more difficult for boys to challenge stereotypes than for girls. © 2014 The Authors. Child Development © 2014 Society for Research in Child Development, Inc.

Can interface features affect aggression resulting from violent video game play? An examination of realistic controller and large screen size.

PubMed

Kim, Ki Joon; Sundar, S Shyam

2013-05-01

Aggressiveness attributed to violent video game play is typically studied as a function of the content features of the game. However, can interface features of the game also affect aggression? Guided by the General Aggression Model (GAM), we examine the controller type (gun replica vs. mouse) and screen size (large vs. small) as key technological aspects that may affect the state aggression of gamers, with spatial presence and arousal as potential mediators. Results from a between-subjects experiment showed that a realistic controller and a large screen display induced greater aggression, presence, and arousal than a conventional mouse and a small screen display, respectively, and confirmed that trait aggression was a significant predictor of gamers' state aggression. Contrary to GAM, however, arousal showed no effects on aggression; instead, presence emerged as a significant mediator.

The psychology of Kant's aesthetics.

PubMed

Guyer, Paul

2008-12-01

Contrary to both his own intentions and the views of both older and more recent commentators. I argue that Kant's aesthetics remains within the confines of eighteenth-century aesthetics as a branch of empirical psychology, as it was then practiced. Kant established a plausible connection between aesthetic experience and judgment on the one hand and cognition in general on the other, through his explanatory concept of the free play of our cognitive powers. However, there is nothing distinctly 'a priori' or 'transcendental' in his claim that this state of mind is what causes our pleasure in beauty or other aesthetic properties. Nor did Kant establish a genuinely a priori or transcendental principle that all human beings have the same disposition to experience a free play of their cognitive powers, let alone in response to the same objects. This failure, however, in no way limits the continuing significance of Kant's aesthetic theory.

Can Virtual Reality Increase the Realism of Role Plays Used to Teach College Women Sexual Coercion and Rape-Resistance Skills?

ERIC Educational Resources Information Center

Jouriles, Ernest N.; McDonald, Renee; Kullowatz, Antje; Rosenfield, David; Gomez, Gabriella S.; Cuevas, Anthony

2009-01-01

The present study evaluated whether virtual reality (VR) can enhance the realism of role plays designed to help college women resist sexual attacks. Sixty-two female undergraduate students were randomly assigned to either the Role Play (RP) or Virtual Role Play (VRP) conditions, which were differentiated only by the use of VR technology in the VRP…

Role-play and the Industrial Revolution: an STS approach to the teaching of steam engines

NASA Astrophysics Data System (ADS)

Sabka, Diego; Pereira de Pereira, Alexsandro; Lima Junior, Paulo

2016-11-01

Role-play is an interesting, although underexplored, way of teaching physics in high school. This paper presents a science-technology-society (STS) approach to the teaching of heat engines based on a role-play of the Industrial Revolution. Enacting the role-play, students are presented not only to scientific concepts, but also to the social and technological controversies of industrial development.

The STRONG STAR Multidisciplinary PTSD Research Consortium

DTIC Science & Technology

2009-09-01

superior A.5 Role of the Serotonin Transporter and Serotonergic Hypotheses related to Alcoholism Vulnerability Due to Low Serotonin. Strong...evidence shows that the biological vulnerability of EOA patients may be related to a serotonergic dysfunction (Johnson, 2000; Johnson and Ait-Daoud...transporter (Johnson et al., 2008). These findings of reduced serotonergic functioning in L-carriers is contrary to previous data indicating that the L

Distributed Leadership in Secondary Schools in England: The Impact on the Role of the Headteacher and Other Issues

ERIC Educational Resources Information Center

Arrowsmith, Trevor

2007-01-01

Distributed leadership (DL) is an emerging form of power distribution in schools which extends authority and influence to groups or individuals in a way which is at least partly contrary to hierarchical arrangements. In this article, the author presents the findings of his study that aimed to answer two questions: (1) What do headteachers do to…

The Role of Structural Characteristics in Problematic Video Game Play: An Empirical Study

ERIC Educational Resources Information Center

King, Daniel L.; Delfabbro, Paul H.; Griffiths, Mark D.

2011-01-01

The research literature suggests that the structural characteristics of video games may play a considerable role in the initiation, development and maintenance of problematic video game playing. The present study investigated the role of structural characteristics in video game playing behaviour within a sample of 421 video game players aged…

Science and Superheroes

ERIC Educational Resources Information Center

Dolenc, Nathan; Wood, Aja; Washburn, Megan; Batson, Yarden; Fan, Brittany; Dickens, Victoria; Armstrong, Shannon

2016-01-01

Role-play has been shown to increase student engagement and improve the overall classroom environment. When used effectively, role-play can transform a task or assignment to appear more like play than work. In this four-part lesson, role-play was used as a teaching strategy to engage students in learning the science and application of several…

The case of "Miss Jacobs": adolescent simulated patients and the quality of their role playing, feedback, and personal impact.

PubMed

Bokken, Lonneke; van Dalen, Jan; Rethans, Jan-Joost

2010-12-01

Adolescents as standardized patients are relatively new in medical education. Studies have mostly explored the impact of role playing on adolescents trained to perform standardized patient roles for assessment purposes. No studies were found with regard to the quality of adolescents' role playing. We evaluated the effects of performing a patient role on adolescents trained as simulated patients (SPs) for teaching purposes (in contrast to standardized patients) and evaluated the quality of adolescent SPs' role playing and feedback. Nine young women, aged 16 to 18 years, were trained to portray roles of adolescents asking their general practitioner for an oral contraceptive. Three adolescent men were trained to portray roles of some of the girls' boyfriends. Each role was developed in consultation with the individual adolescent and was largely based on her own personal experience. Students rated the quality of the adolescent SP's role playing and feedback after each SP encounter on a previously validated questionnaire (the Maastricht Assessment of Simulated Patients). Both the adolescent SPs and faculty teachers both completed questionnaires on their experiences. Three hundred forty-one students rated the quality of the SPs' role playing and feedback with a mean score of 7.5 of 10. The faculty teachers were also generally positive about the role playing and feedback. Nevertheless, there were some concerns about the quality of the feedback. Adolescent SPs reported no negative effects because of their performance. Generally, students and teachers were satisfied with the quality of the role playing and feedback provided by the adolescent SPs. The adolescent SPs experienced no negative effects related to their performance, which confirms earlier findings among adolescent standardized patients.

Leisure Today--the Many Faces of Play.

ERIC Educational Resources Information Center

Hudson, Susan D.; And Others

1995-01-01

This series of papers examines the role of play from various angles, discussing play as an essential human function and universal experience, the role of play in developing cultural values and awareness, a symbolic interactionist view of play, early therapeutic recreation specialists, and the direction of commercialized play. (SM)

Quantifying social influence in an online cultural market.

PubMed

Krumme, Coco; Cebrian, Manuel; Pickard, Galen; Pentland, Sandy

2012-01-01

We revisit experimental data from an online cultural market in which 14,000 users interact to download songs, and develop a simple model that can explain seemingly complex outcomes. Our results suggest that individual behavior is characterized by a two-step process--the decision to sample and the decision to download a song. Contrary to conventional wisdom, social influence is material to the first step only. The model also identifies the role of placement in mediating social signals, and suggests that in this market with anonymous feedback cues, social influence serves an informational rather than normative role.

Quantifying Social Influence in an Online Cultural Market

PubMed Central

Krumme, Coco; Cebrian, Manuel; Pickard, Galen; Pentland, Sandy

2012-01-01

We revisit experimental data from an online cultural market in which 14,000 users interact to download songs, and develop a simple model that can explain seemingly complex outcomes. Our results suggest that individual behavior is characterized by a two-step process–the decision to sample and the decision to download a song. Contrary to conventional wisdom, social influence is material to the first step only. The model also identifies the role of placement in mediating social signals, and suggests that in this market with anonymous feedback cues, social influence serves an informational rather than normative role. PMID:22590493

Does cortisol influence core executive functions? A meta-analysis of acute cortisol administration effects on working memory, inhibition, and set-shifting.

PubMed

Shields, Grant S; Bonner, Joseph C; Moons, Wesley G

2015-08-01

The hormone cortisol is often believed to play a pivotal role in the effects of stress on human cognition. This meta-analysis is an attempt to determine the effects of acute cortisol administration on core executive functions. Drawing on both rodent and stress literatures, we hypothesized that acute cortisol administration would impair working memory and set-shifting but enhance inhibition. Additionally, because cortisol is thought to exert different nongenomic (rapid) and genomic (slow) effects, we further hypothesized that the effects of cortisol would differ as a function of the delay between cortisol administration and cognitive testing. Although the overall analyses were nonsignificant, after separating the rapid, nongenomic effects of cortisol from the slower, genomic effects of cortisol, the rapid effects of cortisol enhanced response inhibition, g+ = 0.113, p=.016, but impaired working memory, g+ = -0.315, p=.008, although these effects reversed over time. Contrary to our hypotheses, there was no effect of cortisol administration on set-shifting. Thus, although we did not find support for the idea that increases in cortisol influence set-shifting, we found that acute increases in cortisol exert differential effects on working memory and inhibition over time. Copyright © 2015 Elsevier Ltd. All rights reserved.

Mechanistic insight into the functional transition of the enzyme guanylate kinase induced by a single mutation

PubMed Central

Zhang, Yuebin; Niu, Huiyan; Li, Yan; Chu, Huiying; Shen, Hujun; Zhang, Dinglin; Li, Guohui

2015-01-01

Dramatic functional changes of enzyme usually require scores of alterations in amino acid sequence. However, in the case of guanylate kinase (GK), the functional novelty is induced by a single (S→P) mutation, leading to the functional transition of the enzyme from a phosphoryl transfer kinase into a phosphorprotein interaction domain. Here, by using molecular dynamic (MD) and metadynamics simulations, we provide a comprehensive description of the conformational transitions of the enzyme after mutating serine to proline. Our results suggest that the serine plays a crucial role in maintaining the closed conformation of wild-type GK and the GMP recognition. On the contrary, the S→P mutant exhibits a stable open conformation and loses the ability of ligand binding, which explains its functional transition from the GK enzyme to the GK domain. Furthermore, the free energy profiles (FEPs) obtained by metadymanics clearly demonstrate that the open-closed conformational transition in WT GK is positive correlated with the process of GMP binding, indicating the GMP-induced closing motion of GK enzyme, which is not observed in the mutant. In addition, the FEPs show that the S→P mutation can also leads to the mis-recognition of GMP, explaining the vanishing of catalytic activity of the mutant. PMID:25672880

Heme-Coordinating Inhibitors of Neuronal Nitric Oxide Synthase. Iron-Thioether Coordination is Stabilized by Hydrophobic Contacts Without Increased Inhibitor Potency

PubMed Central

Martell, Jeffrey D.; Li, Huiying; Doukov, Tzanko; Martásek, Pavel; Roman, Linda J.; Soltis, Michael; Poulos, Thomas L.; Silverman, Richard B.

2010-01-01

The heme-thioether ligand interaction often occurs between heme iron and native methionine ligands, but thioether-based heme-coordinating (type II) inhibitors are uncommon due to the difficulty in stabilizing the Fe-S bond. Here, a thioether-based inhibitor (3) of neuronal nitric oxide synthase (nNOS) was designed, and its binding was characterized by spectrophotometry and crystallography. A crystal structure of inhibitor 3 coordinated to heme iron was obtained, representing, to our knowledge, the first crystal structure of a thioether inhibitor complexed to any heme enzyme. A series of related potential inhibitors (4-8) also were evaluated. Compounds 4-8 were all found to be type I (non-heme-coordinating) inhibitors of ferric nNOS, but 4 and 6-8 were found to switch to type II upon heme reduction to the ferrous state, reflecting the higher affinity of thioethers for ferrous heme than for ferric heme. Contrary to what has been widely thought, thioether-heme ligation was found not to increase inhibitor potency, illustrating the intrinsic weakness of the thioether-ferric heme linkage. Subtle changes in the alkyl groups attached to the thioether sulfur caused drastic changes in binding conformation, indicating that hydrophobic contacts play a crucial role in stabilizing the thioether-heme coordination. PMID:20014790

White matter structure in young adults with familial risk for psychosis - The Oulu Brain and Mind Study.

PubMed

Koivukangas, Jenni; Björnholm, Lassi; Tervonen, Osmo; Miettunen, Jouko; Nordström, Tanja; Kiviniemi, Vesa; Mäki, Pirjo; Jääskeläinen, Erika; Mukkala, Sari; Moilanen, Irma; Barnett, Jennifer H; Jones, Peter B; Nikkinen, Juha; Veijola, Juha

2015-09-30

According to the disconnectivity model, disruptions in neural connectivity play an essential role in the pathology of schizophrenia. The aim of this study was to determine whether these abnormalities are present in young adults with familial risk (FR) for psychosis in the general population based sample. We used diffusion tensor imaging (DTI) and tract-based spatial statistics to compare whole-brain fractional anisotropy, mean diffusivity, and axial and radial diffusion in 47 (17 males) FR subjects to 51 controls (17 males). All the participants were aged between 20 and 25 years and were members of the Northern Finland Birth Cohort 1986 (Oulu Brain and Mind Study). Region of interest analyses were conducted for 12 tracts. Separately, we analysed whole-brain FA for the subgroup with FR for schizophrenia (n=13) compared with 13 gender-matched controls. Contrary to our expectations there were no differences in any of the DTI measures between FR and control groups. This suggests that white matter abnormalities may not be a genetic feature for risk of psychosis and preceding the onset of a psychotic disorder. Our findings do not support the theory of disconnectivity as a primary sign of psychosis in young adults with FR for the illness. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Surface exciton emission of MgO crystals

NASA Astrophysics Data System (ADS)

Kuang, Wen-Jian; Li, Qing; Chen, Yu-Xiang; Hu, Kai; Wang, Ning-Hui; Xing, Fang-Li; Yan, Qun; Sun, Shuai-Shuai; Huang, Yan; Tao, Ye; Tolner, Harm

2013-09-01

MgO crystals have been exposed to vacuum ultraviolet (VUV) radiation from a synchrotron, with energies up to 9 eV, and the emitted light, at wavelengths above 200 nm, was observed. It is concluded that bulk excitons, play an important role in the diffusion of energy inside MgO crystals, resulting in 5.85 eV (212 nm) emission from the MgO terraces of large (0.2-2 µm) MgO : F crystals. In the case of aliovalent impurity doping, then the bulk exciton energy is also transferred to the Vk centres and 5.3 eV (235 nm) light is emitted. Both fluorine and silicon doping appear to promote UV surface emission, acting similarly to an ns2 ion inside MgO, while strong scandium doping is killing the surface emission completely. The 212 nm surface UV emission and the 235 nm bulk UV emission can be excited only at the bandgap edge. Broadband visible light, centred around 400 nm, is also emitted. Contrary to the UV emission, this is not generated when excited at the bandgap edge; instead, we find that it is only excited at sub-bandgap energies, with a maximum at the 5C surface excitation energy of 5.71 eV (217 nm) for the MgO terraces.

Mobility of the native Bacillus subtilis conjugative plasmid pLS20 is regulated by intercellular signaling.

PubMed

Singh, Praveen K; Ramachandran, Gayetri; Ramos-Ruiz, Ricardo; Peiró-Pastor, Ramón; Abia, David; Wu, Ling J; Meijer, Wilfried J J

2013-10-01

Horizontal gene transfer mediated by plasmid conjugation plays a significant role in the evolution of bacterial species, as well as in the dissemination of antibiotic resistance and pathogenicity determinants. Characterization of their regulation is important for gaining insights into these features. Relatively little is known about how conjugation of Gram-positive plasmids is regulated. We have characterized conjugation of the native Bacillus subtilis plasmid pLS20. Contrary to the enterococcal plasmids, conjugation of pLS20 is not activated by recipient-produced pheromones but by pLS20-encoded proteins that regulate expression of the conjugation genes. We show that conjugation is kept in the default "OFF" state and identified the master repressor responsible for this. Activation of the conjugation genes requires relief of repression, which is mediated by an anti-repressor that belongs to the Rap family of proteins. Using both RNA sequencing methodology and genetic approaches, we have determined the regulatory effects of the repressor and anti-repressor on expression of the pLS20 genes. We also show that the activity of the anti-repressor is in turn regulated by an intercellular signaling peptide. Ultimately, this peptide dictates the timing of conjugation. The implications of this regulatory mechanism and comparison with other mobile systems are discussed.

[Responses of antioxidation system of Cynodon dactylon to recirculated landfill leachate irrigation].

PubMed

Wang, Ruyi; He, Pinjing; Shao, Liming; Zhang, Bin; Li, Guojian

2005-05-01

With pot experiment, this paper studied the membrane lipid peroxidation and the variations of antioxidation system in Cynodon dactylon under recirculated landfill leachate irrigation. The results showed that when irrigated with low dilution ratio (< 25%) leachate, the chlorophyll a/b ratio increased with increasing dilution ratio, membrane permeability and MDA and H2O2 contents were in adverse, and membrane lipid peroxidation was relatively weak. However, with the increasing leachate dilution ratio (> 25%), there existed an obvious negative fect on Cynodon dactylon, i.e., the chlorophyll a/b ratio decreased, while cell membrane permeability and MDA and H2O2 contents increased, which meant that the membrane lipid peroxidation was accelerated. The contents antioxidants AsA, GSH and Car also showed the similar trend, i.e., they increased with increasing leachate dilution ratio when irrigated with low dilution ratio leachate, but decreased under medium or high dilution ratio leachate irrigation. Among three test anti-oxidative enzymes, SOD and POD activities showed a similar change test antioxidants, and POD activity was more sensitive, while CAT activity was on the contrary. The contents test antioxidants and the activities of SOD and POD were negatively and significantly correlated to MDA content, indicating that they might play an important role in preventing Cynodon dactylon from cell membrane lipid peroxdation.

The Empathizing-Systemizing Theory, Social Abilities, and Mathematical Achievement in Children

PubMed Central

Escovar, Emily; Rosenberg-Lee, Miriam; Uddin, Lucina Q.; Menon, Vinod

2016-01-01

The Empathizing-Systemizing (E-S) theory describes a profile of traits that have been linked to autism spectrum disorders, and are thought to encompass a continuum that includes typically developing (TD) individuals. Although systemizing is hypothesized to be related to mathematical abilities, empirical support for this relationship is lacking. We examine the link between empathizing and systemizing tendencies and mathematical achievement in 112 TD children (57 girls) to elucidate how socio-cognitive constructs influence early development of mathematical skills. Assessment of mathematical achievement included standardized tests designed to examine calculation skills and conceptual mathematical reasoning. Empathizing and systemizing were assessed using the Combined Empathy Quotient-Child (EQ-C) and Systemizing Quotient-Child (SQ-C). Contrary to our hypothesis, we found that mathematical achievement was not related to systemizing or the discrepancy between systemizing and empathizing. Surprisingly, children with higher empathy demonstrated lower calculation skills. Further analysis using the Social Responsiveness Scale (SRS) revealed that the relationship between EQ-C and mathematical achievement was mediated by social ability rather than autistic behaviors. Finally, social awareness was found to play a differential role in mediating the relationship between EQ-C and mathematical achievement in girls. These results identify empathy, and social skills more generally, as previously unknown predictors of mathematical achievement. PMID:26972835

Teaching science in museums: The pedagogy and goals of museum educators

NASA Astrophysics Data System (ADS)

Tran, Lynn Uyen

2007-03-01

Museum educators have a longstanding presence in museums and play a significant role in the institutions' educational agenda. However, research on field trips to science museums has predominantly explored teachers' and students' perspectives with little acknowledgment of the museum educators who develop and implement the educational programs the students experience. This study sought to describe instruction undertaken in, and goals driving, science museums' lessons through observations of museum educators followed by conversations with them immediately afterwards. Findings showed the ways in which educators adapted their preplanned lessons to the students' interests, needs, and understanding by manipulating the sequence and timing. The data revealed that, contrary to depictions in the research literature of teaching in museums as didactic and lecture oriented, there was creativity, complexity, and skills involved in teaching science in museums. Finally, the educators' teaching actions were predominantly influenced by their affective goals to nurture interests in science and learning. Although their lessons were ephemeral experiences, these educators operated from a perspective, which regarded a school field trip to the science museum, not as a one-time event, but as part of a continuum of visiting such institutions well beyond school and childhood. These findings have implications for the pedagogical practices employed by museum educators, and the relationship between teachers and educators during school field trips, which are discussed.

Interparticle interactions mediated superspin glass to superferromagnetic transition in Ni-bacterial cellulose aerogel nanocomposites

NASA Astrophysics Data System (ADS)

Thiruvengadam, V.; Vitta, Satish

2016-06-01

The interparticle interactions in the magnetic nanocomposites play a dominant role in controlling phase transitions: superparamagnetic to superspin glass and to superferromagnetic. These interactions can be tuned by controlling the size and number density of nanoparticles. The aerogel composites, 0.3Ni-BC and 0.7Ni-BC, consisting of Ni nanoparticles distributed in the bacterial cellulose have been used as a model system to study these interactions. Contrary to conventional approach, size of Ni-nanoparticles is not controlled and allowed to form naturally in bacterial cellulose template. The uncontrolled growth of Ni results in the formation of nanoparticles with 3 different size distributions - <10 nm particles along the length of fibrils, 50 nm particles in the intermediate spaces between the fibrils, and >100 nm particles in voids formed by reticulate structure. At room temperature, the composites exhibit a weakly ferromagnetic behaviour with a coercivity of 40 Oe, which increases to 160 Oe at 10 K. The transition from weakly ferromagnetic state to superferromagnetic state at low temperatures is mediated by the superspin glass state at intermediate temperatures via the interparticle interactions aided by nanoparticles present along the length of fibres. A temperature dependent microstructural model has been developed to understand the magnetic behaviour of nanocomposite aerogels.

Antimicrobial peptides at work: interaction of myxinidin and its mutant WMR with lipid bilayers mimicking the P. aeruginosa and E. coli membranes

NASA Astrophysics Data System (ADS)

Lombardi, Lucia; Stellato, Marco Ignazio; Oliva, Rosario; Falanga, Annarita; Galdiero, Massimiliano; Petraccone, Luigi; D'Errico, Geradino; de Santis, Augusta; Galdiero, Stefania; Del Vecchio, Pompea

2017-03-01

Antimicrobial peptides are promising candidates as future therapeutics in order to face the problem of antibiotic resistance caused by pathogenic bacteria. Myxinidin is a peptide derived from the hagfish mucus displaying activity against a broad range of bacteria. We have focused our studies on the physico-chemical characterization of the interaction of myxinidin and its mutant WMR, which contains a tryptophan residue at the N-terminus and four additional positive charges, with two model biological membranes (DOPE/DOPG 80/20 and DOPE/DOPG/CL 65/23/12), mimicking respectively Escherichia coli and Pseudomonas aeruginosa membrane bilayers. All our results have coherently shown that, although both myxinidin and WMR interact with the two membranes, their effect on membrane microstructure and stability are different. We further have shown that the presence of cardiolipin plays a key role in the WMR-membrane interaction. Particularly, WMR drastically perturbs the DOPE/DOPG/CL membrane stability inducing a segregation of anionic lipids. On the contrary, myxinidin is not able to significantly perturb the DOPE/DOPG/CL bilayer whereas interacts better with the DOPE/DOPG bilayer causing a significant perturbing effect of the lipid acyl chains. These findings are fully consistent with the reported greater antimicrobial activity of WMR against P. aeruginosa compared with myxinidin.

Small interfering RNA mediated Poly (ADP-ribose) Polymerase-1 inhibition upregulates the heat shock response in a murine fibroblast cell line

PubMed Central

2011-01-01

Poly (ADP-ribose) polymerase-1 (PARP-1) is a highly conserved multifunctional enzyme, and its catalytic activity is stimulated by DNA breaks. The activation of PARP-1 and subsequent depletion of nicotinamide adenine dinucleotide (NAD+) and adenosine triphosphate (ATP) contributes to significant cytotoxicity in inflammation of various etiologies. On the contrary, induction of heat shock response and production of heat shock protein 70 (HSP-70) is a cytoprotective defense mechanism in inflammation. Recent data suggests that PARP-1 modulates the expression of a number of cellular proteins at the transcriptional level. In this study, small interfering RNA (siRNA) mediated PARP-1 knockdown in murine wild-type fibroblasts augmented heat shock response as compared to untreated cells (as evaluated by quantitative analysis of HSP-70 mRNA and HSP-70 protein expression). These events were associated with increased DNA binding of the heat shock factor-1 (HSF-1), the major transcription factor of the heat shock response. Co-immunoprecipitation experiments in nuclear extracts of the wild type cells demonstrated that PARP-1directly interacted with HSF-1. These data demonstrate that, in wild type fibroblasts, PARP-1 plays a pivotal role in modulating the heat shock response both through direct interaction with HSF-1 and poly (ADP-ribosylation). PMID:21345219

Dynamics of coral-associated microbiomes during a thermal bleaching event.

PubMed

Pootakham, Wirulda; Mhuantong, Wuttichai; Putchim, Lalita; Yoocha, Thippawan; Sonthirod, Chutima; Kongkachana, Wasitthee; Sangsrakru, Duangjai; Naktang, Chaiwat; Jomchai, Nukoon; Thongtham, Nalinee; Tangphatsornruang, Sithichoke

2018-03-23

Coral-associated microorganisms play an important role in their host fitness and survival. A number of studies have demonstrated connections between thermal tolerance in corals and the type/relative abundance of Symbiodinium they harbor. More recently, the shifts in coral-associated bacterial profiles were also shown to be linked to the patterns of coral heat tolerance. Here, we investigated the dynamics of Porites lutea-associated bacterial and algal communities throughout a natural bleaching event, using full-length 16S rRNA and internal transcribed spacer sequences (ITS) obtained from PacBio circular consensus sequencing. We provided evidence of significant changes in the structure and diversity of coral-associated microbiomes during thermal stress. The balance of the symbiosis shifted from a predominant association between corals and Gammaproteobacteria to a predominance of Alphaproteobacteria and to a lesser extent Betaproteobacteria following the bleaching event. On the contrary, the composition and diversity of Symbiodinium communities remained unaltered throughout the bleaching event. It appears that the switching and/or shuffling of Symbiodinium types may not be the primary mechanism used by P. lutea to cope with increasing seawater temperature. The shifts in the structure and diversity of associated bacterial communities may contribute more to the survival of the coral holobiont under heat stress. © 2018 The Authors. MicrobiologyOpen published by John Wiley & Sons Ltd.

Memory retrieval of everyday information under stress.

PubMed

Stock, Lisa-Marie; Merz, Christian J

2018-07-01

Psychosocial stress is known to crucially influence learning and memory processes. Several studies have already shown an impairing effect of elevated cortisol concentrations on memory retrieval. These studies mainly used learning material consisting of stimuli with a limited ecological validity. When using material with a social contextual component or with educational relevant material both impairing and enhancing stress effects on memory retrieval could be observed. In line with these latter studies, the present experiment also used material with a higher ecological validity (a coherent text consisting of daily relevant numeric, figural and verbal information). After encoding, retrieval took place 24 h later after exposure to psychosocial stress or a control procedure (20 healthy men per group). The stress group was further subdivided into cortisol responders and non-responders. Results showed a significantly impaired retrieval of everyday information in non-responders compared to responders and controls. Altogether, the present findings indicate the need of an appropriate cortisol response for the successful memory retrieval of everyday information. Thus, the present findings suggest that cortisol increases - contrary to a stressful experience per se - seem to play a protective role for retrieving everyday information. Additionally, it could be speculated that the previously reported impairing stress effects on memory retrieval might depend on the used learning material. Copyright © 2018 Elsevier Inc. All rights reserved.

Obesity and nutritional behavior within a historical perspective.

PubMed

Conti, A A; Lippi, D; Gensini, G F

2004-06-01

Obesity is an ever increasing pathological condition in Western countries. Genetic, metabolic, social and cultural factors play different roles in the varying pictures of obesity, together with nutritional behavior. This research proposes to formulate a comparison through the literary sources of the classical world, so as to determine the modalities with which obesity and nutritional habits have been perceived in the past. In Greek and Roman art, obesity often assumed the characteristics of caricature and of satire, confirmed by the elaboration of the stereotype of the sponger. Obesity generated irony and sarcasm; meanwhile the figure of the tyrant too was modelled on the physical type of the obesus, in whom the vice both of alimentary and sexual excess was concentrated. The evaluation of obesity, in the course of the time, has seen alternate phases, that propose different physical models and elaborate different aesthetical canons, but always closely related to a strong social factor as a distinctive sign: opulence. Nowadays obesity is seen, on the contrary, as an ever increasing nutritional disorder, both in prevalence and in incidence, and, to the ideal of the fat subject, very recent years have progressively substituted a different aesthetic typology, also because hyperalimentation has been qualified as a concomitant cause for a number of degenerative disorders.

The Changes in Corneal Astigmatism after Botulinum Toxin-A Injection in Patients with Blepharospasm

PubMed Central

Moon, Nam Ju; Lee, Hyeon Il

2006-01-01

To determine if the involuntary contractions of eyelids may have any effects on the development of corneal astigmatism, we performed this prospective study which includes 19 patients with either essential blepharospasm or hemifacial spasm. In hemifacial spasm, the degree of corneal astigmatism was evaluated between two eyes. Then the topographic changes were checked using vector analysis technique before and after passively opening the eyelids. They were also measured before and at 1 and 6 months after the injection of Botulinum toxin. Resultantly, 20 eyes had the with-the-rule (group1) and 9 eyes against-the-rule (group2) astigmatism. In hemifacial spasm, significantly more astigmatism was found at spastic eyes. The corneal topographic changes after passively opening the eyelids showed 10 eyes with the astigmatic shift to the with-the-rule, while the remaining 19 to the against-the-rule. At 1 month after injection of Botulinum toxin, group 1 showed reduced average corneal astigmatism, whereas group 2 showed increased astigmatism. The astigmatic change vector showed significantly more against-the-rule. In the contrary, 6 months after treatment, corneal astigmatism again increased in group 1 and decreased in group 2. So they took on the appearance of pretreatment astigmatic status eventually. Conclusively eyelids may play an important role in corneal curvature. PMID:16479079

Ocean chemistry controls trends in foraminiferal mineralogy

NASA Astrophysics Data System (ADS)

de Nooijer, Lennart; van Dijk, Inge; Reichart, Gert-Jan

2014-05-01

Foraminifera are unicellular marine protists of which many produce a calcium carbonate shell of either aragonite or calcite. Since they are responsible for a large part of open ocean calcium carbonate precipitation, it is necessary to understand their response to changes in ocean chemistry. On geological time scales, the ratio of Mg over Ca in seawater played an important role in controlling marine aragonite versus calcite mineralogy. Here we reconstructed occurrences of aragonite and low- and high-Mg calcite producing foraminifera through the Phanerozoic. We discovered a two-step impact of seawater chemistry and mass extinction events on the evolution of foraminifera. Seawater Mg to Ca ratios favor production of either calcite, or of high magnesium carbonate and aragonite shells. However, mass extinction events controlled the timing of shifts in dominance from one mineralogy to the other. This observation suggests that ongoing ocean acidification may have important consequences for foraminiferal calcification. Although reduced carbonate saturation state increases dissolution rates of high-Mg calcite and aragonite compared to low-Mg calcite, the current high Mg/Ca of the ocean kinetically favors precipitation of high-Mg calcite and aragonite. Contrary to the differential effects of dissolution, we argue that ongoing ocean acidification is likely to particularly impact calcite producers (e.g. planktonic foraminifera, coccolithophores) compared to those precipitating high-Mg calcite and aragonite (e.g. corals).

Evaporation Kinetics of Laboratory Generated Secondary Organic Aerosols at Elevated Relative Humidity

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

Wilson, Jacqueline M.; Imre, D.; Beranek, Josef

2015-01-06

Secondary organic aerosols (SOA) dominate atmospheric organic aerosols that affect climate, air quality, and health. Recent studies indicate that, contrary to previously held assumptions, at low relative humidity (RH) these particles are semi-solid and evaporate orders of magnitude slower than expected. Elevated relative humidity has the potential to affect significantly formation, properties, and atmospheric evolution of SOA particles. Here we present a study of the effect of RH on the room-temperature evaporation kinetics of SOA particles formed by ozonolysis of α-pinene and limonene. Experiments were carried out on SOA particles generated, evaporated, and aged at 0%, 50% and 90% RH.more » We find that in all cases evaporation begins with a relatively fast phase, during which 30% to 70% of the particle mass evaporates in 2 hours, followed by a much slower evaporation rate. Evaporation kinetics at 0% and 50% RH are nearly the same, while at 90% RH a slightly larger fraction evaporates. In all cases, aging the particles prior to inducing evaporation reduces the evaporative losses, with aging at elevated RH leading to more significant effect. In all cases, SOA evaporation is nearly size-independent, providing direct evidence that oligomers play a crucial role in determining the evaporation kinetics.« less

Analysis of two potential long-distance signaling molecules, LjCLE-RS1/2 and jasmonic acid, in a hypernodulating mutant too much love.

PubMed

Magori, Shimpei; Kawaguchi, Masayoshi

2010-04-01

Legume plants tightly control the number and development of root nodules. This is partly regulated by a long-distance signaling known as auto-regulation of nodulation (AON). AON signaling involves at least two potential long-distance signals: root-derived signal and shoot-derived signal. However, their molecular characteristics and the mode of action remain unclear. In our recent study, we isolated a novel Lotus japonicus hypernodulating mutant too much love (tml). Based on several grafting experiments, we concluded that its causative gene TML functions as a receptor of the shoot-derived signal. This finding prompted us to ask how the candidates of the long-distance signal molecules, LjCLE-RS1/2 and jasmonic acid (JA), are affected in tml mutants. Expression analysis revealed that rapid induction of LjCLE-RS1/2 upon rhizobial inoculation is still intact in tml, supporting that TML plays a role in reception of the shoot-derived signal but not in generation of the root-derived signal. Furthermore, physiological analysis showed that JA, a candidate of the shoot-derived signal, can suppress tml hypernodulation. Therefore, contrary to the previous report, JA might not be a component of AON signaling.

Diabetes Alters Mechanical Properties and Collagen Fiber Re-Alignment in Multiple Mouse Tendons

PubMed Central

Connizzo, Brianne K.; Bhatt, Pankti R.; Liechty, Kenneth W.; Soslowsky, Louis J.

2014-01-01

Tendons function to transfer load from muscle to bone through their complex composition and hierarchical structure, consisting mainly of type I collagen. Recent evidence suggests that type II diabetes may cause alterations in collagen structure, such as irregular fibril morphology and density, which could play a role in the mechanical function of tendons. Using the db/db mouse model of type II diabetes, the diabetic skin was found to have impaired biomechanical properties when compared to the non-diabetic group. The purpose of this study was to assess the effect of diabetes on biomechanics, collagen fiber re-alignment, and biochemistry in three functionally different tendons (Achilles, supraspinatus, patellar) using the db/db mouse model. Results showed that cross-sectional area and stiffness, but not modulus, were significantly reduced in all three tendons. However, the tendon response to load (transition strain, collagen fiber re-alignment) occurred earlier in the mechanical test, contrary to expectations. In addition, the patellar tendon had an altered response to diabetes when compared to the other two tendons, with no changes in fiber realignment and decreased collagen content at the midsubstance of the tendon. Overall, type II diabetes alters tendon mechanical properties and the dynamic response to load. PMID:24833253

Neighborhoods, Schools, and Academic Achievement: A Formal Mediation Analysis of Contextual Effects on Reading and Mathematics Abilities.

PubMed

Wodtke, Geoffrey T; Parbst, Matthew

2017-10-01

Although evidence indicates that neighborhoods affect educational outcomes, relatively little research has explored the mechanisms thought to mediate these effects. This study investigates whether school poverty mediates the effect of neighborhood context on academic achievement. Specifically, it uses longitudinal data from the Panel Study of Income Dynamics, counterfactual methods, and a value-added modeling strategy to estimate the total, natural direct, and natural indirect effects of exposure to an advantaged rather than disadvantaged neighborhood on reading and mathematics abilities during childhood and adolescence. Contrary to expectations, results indicate that school poverty is not a significant mediator of neighborhood effects during either developmental period. Although moving from a disadvantaged neighborhood to an advantaged neighborhood is estimated to substantially reduce subsequent exposure to school poverty and improve academic achievement, school poverty does not play an important mediating role because even the large differences in school composition linked to differences in neighborhood context appear to have no appreciable effect on achievement. An extensive battery of sensitivity analyses indicates that these results are highly robust to unobserved confounding, alternative model specifications, alternative measures of school context, and measurement error, which suggests that neighborhood effects on academic achievement are largely due to mediating factors unrelated to school poverty.

A Simulated Intermediate State for Folding and Aggregation Provides Insights into ΔN6 β2-Microglobulin Amyloidogenic Behavior

PubMed Central

Estácio, Sílvia G.; Krobath, Heinrich; Vila-Viçosa, Diogo; Machuqueiro, Miguel; Shakhnovich, Eugene I.; Faísca, Patrícia F. N.

2014-01-01

A major component of ex vivo amyloid plaques of patients with dialysis-related amyloidosis (DRA) is a cleaved variant of β2-microglobulin (ΔN6) lacking the first six N-terminal residues. Here we perform a computational study on ΔN6, which provides clues to understand the amyloidogenicity of the full-length β2-microglobulin. Contrary to the wild-type form, ΔN6 is able to efficiently nucleate fibrillogenesis in vitro at physiological pH. This behavior is enhanced by a mild acidification of the medium such as that occurring in the synovial fluid of DRA patients. Results reported in this work, based on molecular simulations, indicate that deletion of the N-terminal hexapeptide triggers the formation of an intermediate state for folding and aggregation with an unstructured strand A and a native-like core. Strand A plays a pivotal role in aggregation by acting as a sticky hook in dimer assembly. This study further predicts that the detachment of strand A from the core is maximized at pH 6.2 resulting into higher aggregation efficiency. The structural mapping of the dimerization interface suggests that Tyr10, His13, Phe30 and His84 are hot-spot residues in ΔN6 amyloidogenesis. PMID:24809460

Assessing costs of carrying geolocators using feather corticosterone in two species of aerial insectivore

PubMed Central

Fairhurst, Graham D.; Berzins, Lisha L.; Bradley, David W.; Laughlin, Andrew J.; Romano, Andrea; Romano, Maria; Scandolara, Chiara; Ambrosini, Roberto; Dawson, Russell D.; Dunn, Peter O.; Hobson, Keith A.; Liechti, Felix; Marchant, Tracy A.; Norris, D. Ryan; Rubolini, Diego; Saino, Nicola; Taylor, Caz M.; Whittingham, Linda A.; Clark, Robert G.

2015-01-01

Despite benefits of using light-sensitive geolocators to track animal movements and describe patterns of migratory connectivity, concerns have been raised about negative effects of these devices, particularly in small species of aerial insectivore. Geolocators may act as handicaps that increase energetic expenditure, which could explain reported effects of geolocators on survival. We tested this ‘Energetic Expenditure Hypothesis’ in 12 populations of tree swallows (Tachycineta bicolor) and barn swallows (Hirundo rustica) from North America and Europe, using measurements of corticosterone from feathers (CORTf) grown after deployment of geolocators as a measure of physiology relevant to energetics. Contrary to predictions, neither among- (both species) nor within-individual (tree swallows only) levels of CORTf differed with respect to instrumentation. Thus, to the extent that CORTf reflects energetic expenditure, geolocators apparently were not a strong handicap for birds that returned post-deployment. While this physiological evidence suggests that information about migration obtained from returning geolocator-equipped swallows is unbiased with regard to levels of stress, we cannot discount the possibility that corticosterone played a role in reported effects of geolocators on survival in birds, and suggest that future studies relate corticosterone to antecedent factors, such as reproductive history, and to downstream fitness costs. PMID:26064659

Trophic state changes can affect the importance of methane-derived carbon in aquatic food webs.

PubMed

Schilder, Jos; van Hardenbroek, Maarten; Bodelier, Paul; Kirilova, Emiliya P; Leuenberger, Markus; Lotter, André F; Heiri, Oliver

2017-06-28

Methane-derived carbon, incorporated by methane-oxidizing bacteria, has been identified as a significant source of carbon in food webs of many lakes. By measuring the stable carbon isotopic composition (δ 13 C values) of particulate organic matter, Chironomidae and Daphnia spp. and their resting eggs (ephippia), we show that methane-derived carbon presently plays a relevant role in the food web of hypertrophic Lake De Waay, The Netherlands. Sediment geochemistry, diatom analyses and δ 13 C measurements of chironomid and Daphnia remains in the lake sediments indicate that oligotrophication and re-eutrophication of the lake during the twentieth century had a strong impact on in-lake oxygen availability. This, in turn, influenced the relevance of methane-derived carbon in the diet of aquatic invertebrates. Our results show that, contrary to expectations, methane-derived relative to photosynthetically produced organic carbon became more relevant for at least some invertebrates during periods with higher nutrient availability for algal growth, indicating a proportionally higher use of methane-derived carbon in the lake's food web during peak eutrophication phases. Contributions of methane-derived carbon to the diet of the investigated invertebrates are estimated to have ranged from 0-11% during the phase with the lowest nutrient availability to 13-20% during the peak eutrophication phase. © 2017 The Author(s).

Non-reef environments impact the diversification of extant jacks, remoras and allies (Carangoidei, Percomorpha)

PubMed Central

Marramà, Giuseppe; Carnevale, Giorgio; Santini, Francesco

2016-01-01

Various factors may impact the processes of diversification of a clade. In the marine realm, it has been shown that coral reef environments have promoted diversification in various fish groups. With the exception of requiem sharks, all the groups showing a higher level of diversity in reefs than in non-reef habitats have diets based predominantly on plankton, algae or benthic invertebrates. Here we explore the pattern of diversification of carangoid fishes, a clade that includes numerous piscivorous species (e.g. trevallies, jacks and dolphinfishes), using time-calibrated phylogenies as well as ecological and morphological data from both extant and fossil species. The study of carangoid morphospace suggests that reef environments played a role in their early radiation during the Eocene. However, contrary to the hypothesis of a reef-association-promoting effect, we show that habitat shifts to non-reef environments have increased the rates of morphological diversification (i.e. size and body shape) in extant carangoids. Piscivory did not have a major impact on the tempo of diversification of this group. Through the ecological radiation of carangoid fishes, we demonstrate that non-reef environments may sustain and promote processes of diversification of different marine fish groups, at least those including a large proportion of piscivorous species. PMID:27807262

Music, affect, method, data: reflections on the Carroll versus Kivy debate.

PubMed

Konecni, Vladimir J

2013-01-01

The comprehensive exchange between Noel Carroll and Peter Kivy, which took place in 2007, addressed key issues in the relationship between music and affect. More than in any prior philosophical debate on this topic, experimental psychologists' methods and data played a significant role. However, to a nontrivial extent, the findings-perhaps especially the dubious-were misconstrued or misused, usually without acknowledging the existence of contrary data-based opinion within the psychology of music itself. Therefore, one objective of the present article is to identify the specific problematic features and shed light on the broader context shared by the two disciplines. A complementary goal is to examine contributions to philosophers' transgressions by music psychologists' insufficiently conscientious reporting, frequent overgeneralizations, and unawareness of philosophers' critical arguments. Another objective is to examine the current status of key concepts-the relevant music, basic emotions, mood, expression, induction, movement and dance, and methods (including introspection and experimental procedures)-thus perhaps enabling the discussion of music and affect to proceed with fewer misunderstandings. Finally, the article moves beyond the initial debate and builds on a remarkable agreement of philosophical and psychological opinion on a key issue (the induction of non-basic emotions by absolute music) to reach a new conceptual ground.

The business of ethics: gender, medicine, and the professional codification of the American Physiotherapy Association, 1918-1935.

PubMed

Linker, Beth

2005-07-01

The history of codes of ethics in health care has almost exclusively been told as a story of how medical doctors developed their own professional principles of conduct. Yet telling the history of medical ethics solely from the physicians' perspective neglects not only the numerous allied health care workers who developed their own codes of ethics in tandem with the medical profession, but also the role that gender played in the writing of such professional creeds. By focusing on the predominantly female organization of the American Physiotherapy Association (APA) and its 1935 "Code of Ethics and Discipline," I demonstrate how these women used their creed to at once curry favor from and challenge the authority of the medical profession. Through their Code, APA therapists engaged in a dynamic dialogue with the male physicians of the American Medical Association (AMA) in the name of professional survival. I conclude that, contrary to historians and philosophers who contend that professional women have historically operated under a gender-specific ethic of care, the physiotherapists avoided rhetoric construed as feminine and instead created a "business-like" creed in which they spoke solely about their relationship with physicians and remained silent on the matter of patient care.

Patterns of cortisol and alpha-amylase reactivity to psychosocial stress in maltreated women

PubMed Central

Mielock, Alyssa S.; Morris, Matthew C.; Rao, Uma

2016-01-01

Background Childhood maltreatment can trigger enduring changes in major stress response systems, particularly in the context of major depressive disorder (MDD). However, the relative impact of maltreatment versus MDD on hypothalamic-pituitary-adrenal axis and sympathetic-adrenal-medullary system stress reactivity is not well understood. Method This study examined salivary cortisol and alpha-amylase responses to the Trier Social Stress Test (TSST) in 26 maltreated (15 with current MDD) and 26 non-maltreated (17 with current MDD) women. Results Maltreated women showed greater anticipatory cortisol reactivity during the TSST protocol compared to non-maltreated women. Maltreated women also showed rapid deceleration in cortisol levels. Whereas non-maltreated women showed initial declines in alpha-amylase levels but rapidly increasing alpha-amylase levels during the TSST protocol, maltreated women did not exhibit changes in alpha-amylase levels during the TSST protocol. Contrary to expectation, MDD did not impact cortisol or alpha-amylase responses. Limitations The present study is limited by retrospective report of childhood maltreatment, cross-sectional design, and modest sample sizes. Conclusions These findings suggest that childhood maltreatment plays a greater role driving alterations in cortisol and alpha-amylase stress reactivity than MDD. Understanding the biological embedding of maltreatment is critical for elucidating mechanisms linking these experiences to risk for negative mental and physical health outcomes. PMID:27875756

Intraspecific leaf trait variability along a boreal-to-tropical community diversity gradient

PubMed Central

Bastias, Cristina C.; Fortunel, Claire; Valladares, Fernando; Baraloto, Christopher; Benavides, Raquel; Cornwell, William; Markesteijn, Lars; de Oliveira, Alexandre A.; Sansevero, Jeronimo B. B.; Vaz, Marcel C.; Kraft, Nathan J. B.

2017-01-01

Disentangling the mechanisms that shape community assembly across diversity gradients is a central matter in ecology. While many studies have explored community assembly through species average trait values, there is a growing understanding that intraspecific trait variation (ITV) can also play a critical role in species coexistence. Classic biodiversity theory hypothesizes that higher diversity at species-rich sites can arise from narrower niches relative to species-poor sites, which would be reflected in reduced ITV as species richness increases. To explore how ITV in woody plant communities changes with species richness, we compiled leaf trait data (leaf size and specific leaf area) in a total of 521 woody plant species from 21 forest communities that differed dramatically in species richness, ranging from boreal to tropical rainforests. At each forest, we assessed ITV as an estimate of species niche breadth and we quantified the degree of trait overlap among co-occurring species as a measure of species functional similarity. We found ITV was relatively invariant across the species richness gradient. In addition, we found that species functional similarity increased with diversity. Contrary to the expectation from classic biodiversity theory, our results rather suggest that neutral processes or equalizing mechanisms can be acting as potential drivers shaping community assembly in hyperdiverse forests. PMID:28241033

Large-scale risk assessment of polycyclic aromatic hydrocarbons in shoreline sediments from Saudi Arabia: environmental legacy after twelve years of the Gulf war oil spill.

PubMed

Bejarano, Adriana C; Michel, Jacqueline

2010-05-01

A large-scale assessment of polycyclic aromatic hydrocarbons (PAHs) from the 1991 Gulf War oil spill was performed for 2002-2003 sediment samples (n = 1679) collected from habitats along the shoreline of Saudi Arabia. Benthic sediment toxicity was characterized using the Equilibrium Partitioning Sediment Benchmark Toxic Unit approach for 43 PAHs (ESBTU(FCV,43)). Samples were assigned to risk categories according to ESBTU(FCV,43) values: no-risk (< or = 1), low (>1 - < or = 2), low-medium (>2 - < or = 3), medium (>3 - < or = 5) and high-risk (>5). Sixty seven percent of samples had ESBTU(FCV,43) > 1 indicating potential adverse ecological effects. Sediments from the 0-30 cm layer from tidal flats, and the >30 - <60 cm layer from heavily oiled halophytes and mangroves had high frequency of high-risk samples. No-risk samples were characterized by chrysene enrichment and depletion of lighter molecular weight PAHs, while high-risk samples showed little oil weathering and PAH patterns similar to 1993 samples. North of Safaniya sediments were not likely to pose adverse ecological effects contrary to sediments south of Tanaqib. Landscape and geomorphology has played a role on the distribution and persistence in sediments of oil from the Gulf War. Copyright 2009 Elsevier Ltd. All rights reserved.

Desalination by Membrane Distillation using Electrospun Polyamide Fiber Membranes with Surface Fluorination by Chemical Vapor Deposition.

PubMed

Guo, Fei; Servi, Amelia; Liu, Andong; Gleason, Karen K; Rutledge, Gregory C

2015-04-22

Fibrous membranes of poly(trimethyl hexamethylene terephthalamide) (PA6(3)T) were fabricated by electrospinning and rendered hydrophobic by applying a conformal coating of poly(1H,1H,2H,2H-perfluorodecyl acrylate) (PPFDA) using initiated chemical vapor deposition (iCVD). A set of iCVD-treated electrospun PA6(3)T fiber membranes with fiber diameters ranging from 0.25 to 1.8 μm were tested for desalination using the air gap membrane distillation configuration. Permeate fluxes of 2-11 kg/m2/h were observed for temperature differentials of 20-45 °C between the feed stream and condenser plate, with rejections in excess of 99.98%. The liquid entry pressure was observed to increase dramatically, from 15 to 373 kPa with reduction in fiber diameter. Contrary to expectation, for a given feed temperature the permeate flux was observed to increase for membranes of decreasing fiber diameter. The results for permeate flux and salt rejection show that it is possible to construct membranes for membrane distillation even from intrinsically hydrophilic materials after surface modification by iCVD and that the fiber diameter is shown to play an important role on the membrane distillation performance in terms of permeate flux, salt rejection, and liquid entry pressure.

High-Efficiency Small Molecule-Based Bulk-Heterojunction Solar Cells Enhanced by Additive Annealing.

PubMed

Li, Lisheng; Xiao, Liangang; Qin, Hongmei; Gao, Ke; Peng, Junbiao; Cao, Yong; Liu, Feng; Russell, Thomas P; Peng, Xiaobin

2015-09-30

Solvent additive processing is important in optimizing an active layer's morphology and thus improving the performance of organic solar cells (OSCs). In this study, we find that how 1,8-diiodooctane (DIO) additive is removed plays a critical role in determining the film morphology of the bulk heterojunction OSCs in inverted structure based on a porphyrin small molecule. Different from the cases reported for polymer-based OSCs in conventional structures, the inverted OSCs upon the quick removal of the additive either by quick vacuuming or methanol washing exhibit poorer performance. In contrast, the devices after keeping the active layers in ambient pressure with additive dwelling for about 1 h (namely, additive annealing) show an enhanced power conversion efficiency up to 7.78% with a large short circuit current of 19.25 mA/cm(2), which are among the best in small molecule-based solar cells. The detailed morphology analyses using UV-vis absorption spectroscopy, grazing incidence X-ray diffraction, resonant soft X-ray scattering, and atomic force microscopy demonstrate that the active layer shows smaller-sized phase separation but improved structure order upon additive annealing. On the contrary, the quick removal of the additive either by quick vacuuming or methanol washing keeps the active layers in an earlier stage of large scaled phase separation.