Sample records for chemically aggressive environments

  1. Determination of the neutralization depth of concrete under the aggressive environment influence

    NASA Astrophysics Data System (ADS)

    Morzhukhina, Anastasia; Nikitin, Stanislav; Akimova, Elena

    2018-03-01

    Aggressive environments have a significant impact on destruction of many reinforced concrete structures, such as high-rise constructions or chemical plants. For example, some high-rise constructions are equipped with a swimming pool, so they are exposed to chloride ions in the air. Penetration of aggressive chemical substances into the body of concrete contributes to acceleration of reinforced concrete structure corrosion that in turn leads to load bearing capacity loss and destruction of the building. The article considers and analyzes the main technologies for calculating penetration depth of various aggressive substances into the body of concrete. The calculation of corrosion depth was made for 50-year service life.

  2. Environment assisted degradation mechanisms in advanced light metals

    NASA Technical Reports Server (NTRS)

    Gangloff, R. P.; Stoner, G. E.; Swanson, R. E.

    1989-01-01

    A multifaceted research program on the performance of advanced light metallic alloys in aggressive aerospace environments, and associated environmental failure mechanisms was initiated. The general goal is to characterize alloy behavior quantitatively and to develop predictive mechanisms for environmental failure modes. Successes in this regard will provide the basis for metallurgical optimization of alloy performance, for chemical control of aggressive environments, and for engineering life prediction with damage tolerance and long term reliability.

  3. Photoperiod and aggression induce changes in ventral gland compounds exclusively in male Siberian hamsters.

    PubMed

    Rendon, Nikki M; Soini, Helena A; Scotti, Melissa-Ann L; Weigel, Ellen R; Novotny, Milos V; Demas, Gregory E

    2016-05-01

    Chemical communication is a critical component of social behavior as it facilitates social encounters, allows for evaluation of the social partner, defines territories and resources, and advertises information such as sex and physiological state of an animal. Odors provide a key source of information about the social environment to rodents; however, studies identifying chemical compounds have thus far focused primarily on few species, particularly the house mouse. Moreover, considerably less attention has been focused on how environmental factors, reproductive phenotype, and behavioral context alter these compounds outside of reproduction. We examined the effects of photoperiod, sex, and social context on chemical communication in the seasonally breeding Siberian hamster. We sampled ventral gland secretions in both male and female hamsters before and after an aggressive encounter and identified changes in a range of volatile compounds. Next, we investigated how photoperiod, reproductive phenotype, and aggression altered ventral gland volatile compound composition across the sexes. Males exhibited a more diverse chemical composition, more sex-specific volatiles, and showed higher levels of excretion compared to females. Individual volatiles were also differentially excreted across photoperiod and reproductive phenotype, as well as differentially altered in response to an aggressive encounter. Female volatile compound composition, in contrast, did not differ across photoperiods or in response to aggression. Collectively, these data contribute to a greater understanding of context-dependent changes in chemical communication in a seasonally breeding rodent. Copyright © 2016 Elsevier Inc. All rights reserved.

  4. AN INVESTIGATION OF THE CHEMICAL STABILITY OF ARSENOSUGARS IN SIMULATED GASTRIC JUICE AND ACIDIC ENVIRONMENTS USING IC-ICP-MS AND IC-ESI-MS/MS

    EPA Science Inventory

    A more quantitative extraction of arsenic-containing compounds from seafood matrices is essential in developing better dietary exposure estimates. More quantitative extraction often implies a more chemically aggressive set of extraction conditions. However, these conditions may...

  5. Environment assisted degradation mechanisms in advanced light metals

    NASA Technical Reports Server (NTRS)

    Gangloff, Richard P.; Stoner, Glenn E.; Swanson, Robert E.

    1988-01-01

    The general goals of the research program are to characterize alloy behavior quantitatively and to develop predictive mechanisms for environmental failure modes. Successes in this regard will provide the basis for metallurgical optimization of alloy performance, for chemical control of aggressive environments, and for engineering life prediction with damage tolerance and long term reliability.

  6. Ophthalmic optical coatings: The real world can be more aggressive than you think

    NASA Astrophysics Data System (ADS)

    Mildebrath, Mark; Klemm, Karl

    2007-01-01

    Ophthalmic antireflection coatings are not normally considered to be in the same category as other traditional optical coatings with respect to environmental damage. However, as a group, eyeglass lens wearers tend to subject their optical-coated eyewear to a broader and more aggressive range of environmental aggressions than at first imagined. This paper presents the environmental aggressions and, in some detail, the resultant coating defects observed in coated ophthalmic optics. Further, development of test methods for defect replication, to enable product improvements will be discussed. Real-life environments combine thermal, chemical, and mechanical "aggressions" which spectacle lenses are subjected to. These aggressions generate optical coating defects and failure modes involving abrasion, corrosion, and loss of adhesion. In addition, market forces driven by retail customer perceptions lead to product liabilities not normally considered to be of any consequence in traditional optical coating applications.

  7. Refractory Materials for Flame Deflector Protection System Corrosion Control: Coatings Systems Literature Survey

    NASA Technical Reports Server (NTRS)

    Calle, Luz M.; Hintze, Paul E.; Parlier, Christopher R.; Sampson, Jeffrey W.; Coffman, Brekke E.; Coffman, Brekke E.; Curran, Jerome P.; Kolody, Mark R.; Whitten, Mary; Perisich, Steven; hide

    2009-01-01

    When space vehicles are launched, extreme heat, exhaust, and chemicals are produced and these form a very aggressive exposure environment at the launch complex. The facilities in the launch complex are exposed to this aggressive environment. The vehicle exhaust directly impacts the flame deflectors, making these systems very susceptible to high wear and potential failure. A project was formulated to develop or identify new materials or systems such that the wear and/or damage to the flame deflector system, as a result of the severe environmental exposure conditions during launches, can be mitigated. This report provides a survey of potential protective coatings for the refractory concrete lining on the steel base structure on the flame deflectors at Kennedy Space Center (KSC).

  8. Moderating effects of family environment on the association between children's aggressive beliefs and their aggression trajectories from childhood to adolescence.

    PubMed

    Andreas, Jasmina Burdzovic; Watson, Malcolm W

    2009-01-01

    This study explored how children's aggressive beliefs and their family environments combine to influence the development of child aggression from middle childhood into adolescence. We utilized a "variable-centered" empirical approach, specifically examining whether children's aggressive beliefs represent a risk factor for their aggressive behaviors and whether this risk can be moderated by children's family environment. These questions were tested with individual growth modeling, using the data from a community-representative sample of 440 mother-child dyads, interviewed four times over a 6-year study period. The accelerated longitudinal design of the study enabled examination of children's aggression trajectories from age 7 to age 19. The results supported the hypothesis that elevated aggressive beliefs in children represent a risk factor for aggression, as higher aggressive beliefs were associated with greater aggression at the youngest age, as well as with increased aggression over time. However, as hypothesized, family environment moderated this association, such that changes in children's aggression over time were contingent upon the interaction of their aggressive beliefs with family environment. Specifically, aggression was reduced in children with high aggressive beliefs if they experienced better than average family environment, which included less family conflict and more family cohesion.

  9. Moderating effects of family environment on the association between children’s aggressive beliefs and their aggression trajectories from childhood to adolescence

    PubMed Central

    ANDREAS, JASMINA BURDZOVIC; WATSON, MALCOLM W.

    2009-01-01

    This study explored how children’s aggressive beliefs and their family environments combine to influence the development of child aggression from middle childhood into adolescence. We utilized a “variable-centered” empirical approach, specifically examining whether children’s aggressive beliefs represent a risk factor for their aggressive behaviors and whether this risk can be moderated by children’s family environment. These questions were tested with individual growth modeling, using the data from a community-representative sample of 440 mother–child dyads, interviewed four times over a 6-year study period. The accelerated longitudinal design of the study enabled examination of children’s aggression trajectories from age 7 to age 19. The results supported the hypothesis that elevated aggressive beliefs in children represent a risk factor for aggression, as higher aggressive beliefs were associated with greater aggression at the youngest age, as well as with increased aggression over time. However, as hypothesized, family environment moderated this association, such that changes in children’s aggression over time were contingent upon the interaction of their aggressive beliefs with family environment. Specifically, aggression was reduced in children with high aggressive beliefs if they experienced better than average family environment, which included less family conflict and more family cohesion. PMID:19144230

  10. Experimental Study on Modification of Concrete with Asphalt Admixture

    NASA Astrophysics Data System (ADS)

    Bołtryk, Michał; Małaszkiewicz, Dorota; Pawluczuk, Edyta

    2017-10-01

    Durability of engineering structures made of cement concrete with high compressive strength is a very vital issue, especially when they are exposed to different aggressive environments and dynamic loads. Concrete resistance to weathering actions and chemical attack can be improved by combined chemical and mechanical modification of concrete microstructure. Asphalt admixture in the form of asphalt paste (AP) was used for chemical modification of cement composite microstructure. Concrete structure was formed using special technology of compaction. A stand for vibro-vibropressing with regulated vibrator force and pressing force was developed. The following properties of the modified concrete were tested: compressive strength, water absorption, freeze-thaw resistance, scaling resistance in the presence of de-icing agents, chloride migration, resistance to CO2 and corrosion in aggressive solutions. Corrosion resistance was tested alternately in 1.8% solutions of NH4Cl, MgSO4, (NH2)2CO and CaCl2, which were altered every 7 days; the experiment lasted 9.5 months. Optimum compaction parameters in semi-industrial conditions were determined: ratio between piston stress (Qp ) and external top vibrator force (Po ) in the range 0.4÷-0.5 external top vibrator force 4 kN. High strength concretes with compressive strength fcm = 60÷70 MPa, very low water absorption (<1%) and high resistance to aggressive environments were obtained in this study. AP content was reduced from 10% (previous investigations) to 2-4% of cement mass thanks to the special compaction method. Excellent chloride ion penetration resistance and carbonation resistance of concrete containing AP admixture is due to the asphalt barrier formed in pores of cement hydrates against dioxide and chloride ions. Concrete specimens containing AP 4% c.m. and consolidated by vibro-vibropressing method proved to be practically resistant to highly corrosive environment. Vibro-vibropressing compaction technology of concrete modified with AP can be applied in prefabrication plants to produce elements for road, bridge and hydraulic engineering constructions.

  11. A general strategy for the ultrafast surface modification of metals.

    PubMed

    Shen, Mingli; Zhu, Shenglong; Wang, Fuhui

    2016-12-07

    Surface modification is an essential step in engineering materials that can withstand the increasingly aggressive environments encountered in various modern energy-conversion systems and chemical processing industries. However, most traditional technologies exhibit disadvantages such as slow diffusion kinetics, processing difficulties or compatibility issues. Here, we present a general strategy for the ultrafast surface modification of metals inspired by electromigration, using aluminizing austenitic stainless steel as an example. Our strategy facilitates the rapid formation of a favourable ductile surface layer composed of FeCrAl or β-FeAl within only 10 min compared with several hours in conventional processes. This result indicates that electromigration can be used to achieve the ultrafast surface modification of metals and can overcome the limitations of traditional technologies. This strategy could be used to aluminize ultra-supercritical steam tubing to withstand aggressive oxidizing environments.

  12. Social interactions promote adaptive resource defense in ants

    PubMed Central

    Heeb, Eva Linda; Neupert, Stefanie

    2017-01-01

    Social insects vigorously defend their nests against con- and heterospecific competitors. Collective defense is also seen at highly profitable food sources. Aggressive responses are elicited or promoted by several means of communication, e.g. alarm pheromones and other chemical markings. In this study, we demonstrate that the social environment and interactions among colony members (nestmates) modulates the propensity to engage in aggressive behavior and therefore plays an important role in allocating workers to a defense task. We kept Formica rufa workers in groups or isolated for different time spans and then tested their aggressiveness in one-on-one encounters with other ants. In groups of more than 20 workers that are freely interacting, individuals are aggressive in one-on-one encounters with non-nestmates, whereas aggressiveness of isolated workers decreases with increasing isolation time. We conclude that ants foraging collectively and interacting frequently, e.g. along foraging trails and at profitable food sources, remain in a social context and thereby maintain high aggressiveness against potential competitors. Our results suggest that the nestmate recognition system can be utilized at remote sites for an adaptive and flexible tuning of the response against competitors. PMID:28910322

  13. Superhydrophobic properties induced by sol-gel routes on copper surfaces

    NASA Astrophysics Data System (ADS)

    Raimondo, M.; Veronesi, F.; Boveri, G.; Guarini, G.; Motta, A.; Zanoni, R.

    2017-11-01

    Superhydrophobic surfaces are attracting increasing attention in different fields such as energy, transportation, building industry and electronics, as they exhibit many interesting properties such as high water repellence, anti-fogging, anti-corrosion, anti-fouling and self-cleaning abilities. Here, superhydrophobic nanostructured hybrid materials obtained by depositing alumina nanoparticles on copper surfaces via dip coating in Al2O3 sol are presented. Two different preparation routes were explored, based on either an alcoholic or an aqueous Al2O3 sol, and the resulting wetting properties were compared. Wettability measurements showed that when the alcoholic sol is used superhydrophobicity is attained, with values of water contact angle very close to the upper limit of 180°, while highly hydrophobic coatings are obtained with the aqueous sol. These findings were further supported by electron microscopy and X-ray photoelectron spectroscopy, which revealed that the surface layer deposited on Cu is more homogenous and richer in alumina nanoparticles when the alcoholic sol was used. Durability of the superhydrophobic coating was assessed by performing ageing tests in chemically aggressive environments. A remarkable resistance is displayed by the superhydrophobic coating in acid environment, while alkaline conditions severely affect its properties. Such behaviors were investigated by XPS and FE-SEM measurements, which disclosed the nature of the surface reactions under the different conditions tested. The present results underline that a thorough investigation of surface morphology, chemical composition and wetting properties reveals their strongly connection and helps optimizing the combination of substrate nanostructuring and suitable chemical coating for an improved durability in different aggressive environments.

  14. A general strategy for the ultrafast surface modification of metals

    PubMed Central

    Shen, Mingli; Zhu, Shenglong; Wang, Fuhui

    2016-01-01

    Surface modification is an essential step in engineering materials that can withstand the increasingly aggressive environments encountered in various modern energy-conversion systems and chemical processing industries. However, most traditional technologies exhibit disadvantages such as slow diffusion kinetics, processing difficulties or compatibility issues. Here, we present a general strategy for the ultrafast surface modification of metals inspired by electromigration, using aluminizing austenitic stainless steel as an example. Our strategy facilitates the rapid formation of a favourable ductile surface layer composed of FeCrAl or β-FeAl within only 10 min compared with several hours in conventional processes. This result indicates that electromigration can be used to achieve the ultrafast surface modification of metals and can overcome the limitations of traditional technologies. This strategy could be used to aluminize ultra-supercritical steam tubing to withstand aggressive oxidizing environments. PMID:27924909

  15. Phoretic nest parasites use sexual deception to obtain transport to their host's nest.

    PubMed

    Saul-Gershenz, Leslie S; Millar, Jocelyn G

    2006-09-19

    Cooperative behaviors are common among social insects such as bees, wasps, ants, and termites, but they have not been reported from insect species that use aggressive mimicry to manipulate and exploit prey or hosts. Here we show that larval aggregations of the blister beetle Meloe franciscanus, which parasitize nests of the solitary bee Habropoda pallida, cooperate to exploit the sexual communication system of their hosts by producing a chemical cue that mimics the sex pheromone of the female bee. Male bees are lured to larval aggregations, and upon contact (pseudocopulation) the beetle larvae attach to the male bees. The larvae transfer to female bees during mating and subsequently are transported to the nests of their hosts. To mimic the chemical and visual signals of female bees effectively, the parasite larvae must cooperate, emphasizing the adaptive value of cooperation between larvae. The aggressive chemical mimicry by the beetle larvae and their subsequent transport to their hosts' nests by the hosts themselves provide an efficient solution to the problem of locating a critical but scarce resource in a harsh environment.

  16. The effects of environmental resource and security on aggressive behavior.

    PubMed

    Ng, Henry Kin Shing; Chow, Tak Sang

    2017-05-01

    Exposure to different environments has been reported to change aggressive behavior, but previous research did not consider the underlying elements that caused such an effect. Based on previous work on environmental perception, we examined the role of environmental resource and security in altering aggression level. In three experiments, participants were exposed to environments that varied in resource (High vs. Low) and security (High vs. Low) levels, after which aggression was measured. The environments were presented through visual priming (Experiments 1-2) and a first-person gameplay (Experiment 3). We observed a consistent resource-security interaction effect on aggression, operationalized as the level of noise blast (Experiment 1) and number of unpleasant pictures (Experiments 2-3) delivered to strangers by the participants. High resource levels associated with higher aggression in insecure conditions, but lower aggression in secure conditions. The findings suggest that the adaptive value of aggression varies under different environmental constraints. Implications are discussed in terms of the effects of adverse environments on aggression, and the nature's effects on social behavior. Aggr. Behav. 43:304-314, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  17. On a Thermodynamic Approach to Material Selection for Service in Aggressive Multi-Component Gaseous and/or Vapor Environments

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

    Glazoff, Michael Vasily; Marschman, Steven Craig; Soelberg, Nicholas Ray

    This report fulfills the M4 milestone, M4FT-15IN08020110 UNF Analysis Support, under Work Package Number FT-15IN080201. The issue of materials selection for many engineering applications represents an important problem, particularly in cases where material failure is possible as a result of corrosive environments. For example, 304 dual purpose or 316 stainless steel is used in the construction of many used nuclear fuel storage canisters. Deployed all over the world, these canisters are housed inside shielded enclosures and cooled passively by convective airflow. When located along seaboards or particular industrial areas, salt, other corrosive chemicals, and moisture can become entrained in themore » air that cools the canisters. It is important to develop an understanding of what impact, if any, that chemical environment will have on those canisters. In many cases of corrosion in aggressive gaseous environments, the material selection process is based on some general recommendations, anecdotal evidence, and/or the past experience of that particular project’s participants. For gaseous mixtures, the theoretical basis is practically limited to the construction of the so-called “Ellingham diagrams” for pure metals. These plots predict the equilibrium temperature between different individual metals, their respective oxides, and oxygen gas. Similar diagrams can be constructed for the reactions with sulfur, nitrogen, carbon, etc. In the generalization of this approach by Richardson and Jeffes, additional scales can be superimposed upon an Ellingham diagram that would correspond to different gaseous mixtures, e.g. CO/CO 2, or H 2/H 2O. However, while the general approach to predicting the stability of a multi-component heterogeneous alloy (e.g., steel or a superalloy) in a multi-component aggressive gaseous environment was developed in very general form, actual examples of its applications to concrete real-life problems are practically absent. This is related to alloy design, corrosion protection, and material selection for different applications. In this work, an effort was made to advance in that direction using modern computational thermodynamics methodology, software, and databases by Thermo-Calc Inc. The developed methodology is illustrated by the case study – a process of nuclear waste immobilization using a chemical engineering approach described below. The developed methodology can be considered a practical illustration of the Ellingham approach generalization and could be used for obtaining thermodynamic guidance on a given process’ feasibility using equipment/sensors made of a particular multicomponent heterogeneous metallic alloy.« less

  18. Family and Social Environmental Factors Associated with Aggression among Chinese Adolescents

    ERIC Educational Resources Information Center

    Dou, Chunxia; Wei, Zhen; Jin, Ke; Wang, He; Wang, Xiulan; Peng, Ziwen

    2015-01-01

    Family and school environments are assumed to be associated with and influence aggressive behaviors. However, which specific risk factors within these environments that are associated with aggressive behavior are unclear. The goal of this study is to identify family and social environmental qualities that are related to aggression among Chinese…

  19. Early-life experience affects honey bee aggression and resilience to immune challenge

    PubMed Central

    Rittschof, Clare C.; Coombs, Chelsey B.; Frazier, Maryann; Grozinger, Christina M.; Robinson, Gene E.

    2015-01-01

    Early-life social experiences cause lasting changes in behavior and health for a variety of animals including humans, but it is not well understood how social information ‘‘gets under the skin’’ resulting in these effects. Adult honey bees (Apis mellifera) exhibit socially coordinated collective nest defense, providing a model for social modulation of aggressive behavior. Here we report for the first time that a honey bee’s early-life social environment has lasting effects on individual aggression: bees that experienced high-aggression environments during pre-adult stages showed increased aggression when they reached adulthood relative to siblings that experienced low-aggression environments, even though all bees were kept in a common environment during adulthood. Unlike other animals including humans however, high-aggression honey bees were more, rather than less, resilient to immune challenge, assessed as neonicotinoid pesticide susceptibility. Moreover, aggression was negatively correlated with ectoparasitic mite presence. In honey bees, early-life social experience has broad effects, but increased aggression is decoupled from negative health outcomes. Because honey bees and humans share aspects of their physiological response to aggressive social encounters, our findings represent a step towards identifying ways to improve individual resiliency. Pre-adult social experience may be crucial to the health of the ecologically threatened honey bee. PMID:26493190

  20. Performance and modeling of cesium ion exchange by ENGI neered form crystalline silicotitanates

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

    Anthony, R.G.; Gu, D.; Huckman, M.

    1996-10-01

    TAM-5, a hydrous crystalline silicotitanate (CST) powder developed by Sandia National Laboratories and Texas A&M University, and commercialized by UOP as IONSIV{reg_sign} Ion Exchanger Type IE-910, is a highly selective material for removing cesium and strontium from aqueous radioactive wastes such as those found at the Hanford site in Washington. An engineered form of the material suitable for column ion exchange type operations has been developed and tested. Data relevant to processing radioactive tank wastes including equilibrium distribution coefficients and column testing will be presented. The impact of exposure of the engineered form to chemically aggressive environments such as itmore » might experience during waste processing, and to the less aggressive environments it might experience during post processing storage has been assessed. The thermal stability of the material has also been evaluated. The experimental results have been integrated with an effort to model the material`s equilibrium and kinetic behavior.« less

  1. [Endoscopic diagnosis of local chemical burn of mucous membranes of the stomach, induced with the purpose of simulation of gastric ulcer].

    PubMed

    Byzov, N V; Plekhanov, V N

    2013-01-01

    With the purpose of improvement of diagnosis of induced gastric ulcer were examined 11 patients who took aggressive agents for simulation of gastric ulcer and 33 patients who took pseudo-aggressive agents. Observables, conduced diagnosis of local chemical burn of mucous coat of stomach during initial 6 days after taking aggressive agents. Stages of ulcerous process, resulting from local chemical burn of mucous coat of stomach, coressponds to real gactric ulcer. Gelatin capsule using as a container for delivery of aggressive agents, melts in stomach in 5-6 minutes after taking. Independent from body position, mucous coat of greater curvature of the stomach is damaged. It is impossible to simulate duodenal bulb ulcer using the gelatine capsule or ball made of breadcrumb. The last method of delivery of aggressive agent can damage the small intestine because of uncontrollability of the place of breaking the ball.

  2. Genomic Analysis of Genotype-by-Social Environment Interaction for Drosophila melanogaster Aggressive Behavior.

    PubMed

    Rohde, Palle Duun; Gaertner, Bryn; Ward, Kirsty; Sørensen, Peter; Mackay, Trudy F C

    2017-08-01

    Human psychiatric disorders such as schizophrenia, bipolar disorder, and attention-deficit/hyperactivity disorder often include adverse behaviors including increased aggressiveness. Individuals with psychiatric disorders often exhibit social withdrawal, which can further increase the probability of conducting a violent act. Here, we used the inbred, sequenced lines of the Drosophila Genetic Reference Panel (DGRP) to investigate the genetic basis of variation in male aggressive behavior for flies reared in a socialized and socially isolated environment. We identified genetic variation for aggressive behavior, as well as significant genotype-by-social environmental interaction (GSEI); i.e. , variation among DGRP genotypes in the degree to which social isolation affected aggression. We performed genome-wide association (GWA) analyses to identify genetic variants associated with aggression within each environment. We used genomic prediction to partition genetic variants into gene ontology (GO) terms and constituent genes, and identified GO terms and genes with high prediction accuracies in both social environments and for GSEI. The top predictive GO terms significantly increased the proportion of variance explained, compared to prediction models based on all segregating variants. We performed genomic prediction across environments, and identified genes in common between the social environments that turned out to be enriched for genome-wide associated variants. A large proportion of the associated genes have previously been associated with aggressive behavior in Drosophila and mice. Further, many of these genes have human orthologs that have been associated with neurological disorders, indicating partially shared genetic mechanisms underlying aggression in animal models and human psychiatric disorders. Copyright © 2017 by the Genetics Society of America.

  3. Corrosion of titanium: Part 1: aggressive environments and main forms of degradation.

    PubMed

    Prando, Davide; Brenna, Andrea; Diamanti, Maria Vittoria; Beretta, Silvia; Bolzoni, Fabio; Ormellese, Marco; Pedeferri, MariaPia

    2017-11-11

    Titanium has outstanding corrosion resistance due to the external natural oxide protective layer formed when it is exposed to an aerated environment. Despite this, titanium may suffer different forms of corrosion in severe environments: uniform corrosion, pitting and crevice corrosion, hydrogen embrittlement, stress-corrosion cracking, fretting corrosion and erosion. In this first review, forms of corrosion affecting titanium are analyzed based on a wide literature review. For each form of corrosion, the mechanism and most severe environment are reported according to the current understanding.In the second part, this review will address the possible surface treatments that can increase corrosion resistance on commercially pure titanium: Electrochemical anodizing, thermal oxidation, chemical oxidation and bulk treatments such as alloying will be considered, highlighting the advantages of each technique.

  4. Iranian nurses' experiences of aggression in psychiatric wards: a qualitative study.

    PubMed

    Moghadam, Malek Fereidooni; Pazargadi, Mehrnoosh; Khoshknab, Masoud Fallahi

    2013-10-01

    Aggression from psychiatric patients is a constant problem for care providers that causes major problems in the therapeutic environment, and may have negative effects on the quality of care. Since recognition of aggression with regard to cultural background leads to better control of aggression in the psychiatric wards, this study has been done to clarify Iranian nurses' experiences of aggression in psychiatric wards. A qualitative content analysis study was conducted to explore experiences of nurses. Data analysis revealed four themes: (1) Damage resulting from aggression, (2) Aggression catalysts, (3) Contagious nature of aggression, and (4) Various control strategies. There are various causes for in-patients' aggression, and nurses use various approaches to control it. These approaches are influenced by personnel, facilities, and ward environment. Identifying these factors and strategies can contribute to better management of aggression and, thus, better quality of care in psychiatric wards.

  5. Bad nights or bad bars? Multi-level analysis of environmental predictors of aggression in late-night large-capacity bars and clubs.

    PubMed

    Graham, Kathryn; Bernards, Sharon; Osgood, D Wayne; Wells, Samantha

    2006-11-01

    To clarify environmental predictors of bar-room aggression by differentiating relationships due to nightly variations versus across bar variations, frequency versus severity of aggression and patron versus staff aggression. Male-female pairs of researcher-observers conducted 1334 observations in 118 large capacity (> 300) bars and clubs in Toronto, Canada. Observers independently rated aspects of the environment (e.g. crowding) at every visit and wrote detailed narratives of each incident of aggression that occurred. Measures of severity of aggression for the visit were calculated by aggregating ratings for each person in aggressive incidents. Although bivariate analyses confirmed the significance of most environmental predictors of aggression identified in previous research, multivariate analyses identified the following key visit-level predictors (controlling for bar-level relationships): rowdiness/permissive environment and people hanging around after closing predicted both frequency and severity of aggression; sexual activity, contact and competition and people with two or more drinks at closing predicted frequency but not severity of aggression; lack of staff monitoring predicted more severe patron aggression, while having more and better coordinated staff predicted more severe staff aggression. Intoxication of patrons was significantly associated with more frequent and severe patron aggression at the bar level (but not at the visit level) in the multivariate analyses and negatively associated with severity of staff aggression at the visit level. The results demonstrate clearly the importance of the immediate environment (not just the type of bar or characteristics of usual patrons) and the importance of specific environmental factors, including staff behaviour, in predicting both frequency and severity of aggression.

  6. Social determinants of aggression in a sample of Chinese primary school children.

    PubMed

    Ekblad, S

    1986-05-01

    The aim of the present study was to relate children's aggression levels to social determinants of interest (i.e., child-rearing measures, day-care attendance, peer group influence, and TV-watching) in a sample of Chinese children in the People's Republic of China. A sample of 290 primary school students (155 boys and 135 girls, mean age 10.3) in grade four in Beijing were investigated using the Multi-Faceted Aggression Inventory. The children's parents were asked about child-rearing measures and day-care experience for the child. Teachers rated the children's aggression, school achievement level, and membership in the Young Pioneers. Despite acknowledged limitations, the findings in this study gave evidence that according to a person-environment interaction perspective, the Chinese children's individual differences in aggression were influenced by the restricted environment. As aggressive behaviour is undesired and suppressed in the Chinese culture in and outside the home, the Chinese children seemed to show lower levels and less variation of aggression behaviour than children in permissive environments (e.g., Sweden). However, when analysing sex differences in aggression environmental influences alone might not explain the differences.

  7. Physical and verbal aggressive behavior and COMT genotype: Sensitivity to the environment.

    PubMed

    Tuvblad, Catherine; Narusyte, Jurgita; Comasco, Erika; Andershed, Henrik; Andershed, Anna-Karin; Colins, Olivier F; Fanti, Kostas A; Nilsson, Kent W

    2016-07-01

    Catechol-O-methyltransferase (COMT) genotype has been implicated as a vulnerability factor for several psychiatric diseases as well as aggressive behavior, either directly, or in interaction with an adverse environment. The present study aimed at investigating the susceptibility properties of COMT genotype to adverse and favorable environment in relation to physical and verbal aggressive behavior. The COMT Val158Met polymorphism was genotyped in a Swedish population-based cohort including 1,783 individuals, ages 20-24 years (47% males). A significant three-way interaction was found, after correction for multiple testing, between COMT genotype, exposure to violence, and parent-child relationship in association with physical but not verbal aggressive behavior. Homozygous for the Val allele reported lower levels of physical aggressive behavior when they were exposed to violence and at the same time experienced a positive parent-child relationship compared to Met carriers. Thus, susceptibility properties of COMT genotype were observed in relation to physical aggressive behavior supporting the hypothesis that COMT genotypes are modifying the sensitivity to environment that confers either risk or protection for aggressive behavior. As these are novel findings, they warrant further investigation and replication in independent samples. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  8. Effects of a modular two-step ozone-water and annealing process on silicon carbide graphene

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

    Webb, Matthew J., E-mail: matthew.webb@cantab.net; Lundstedt, Anna; Grennberg, Helena

    By combining ozone and water, the effect of exposing epitaxial graphene on silicon carbide to an aggressive wet-chemical process has been evaluated after high temperature annealing in ultra high vacuum. The decomposition of ozone in water produces a number of oxidizing species, however, despite long exposure times to the aqueous-ozone environment, no graphene oxide was observed after the two-step process. The systems were comprehensively characterized before and after processing using Raman spectroscopy, core level photoemission spectroscopy, and angle resolved photoemission spectroscopy together with low energy electron diffraction, low energy electron microscopy, and atomic force microscopy. In spite of the chemicalmore » potential of the aqueous-ozone reaction environment, the graphene domains were largely unaffected raising the prospect of employing such simple chemical and annealing protocols to clean or prepare epitaxial graphene surfaces.« less

  9. Rigorous tests of gene-environment interactions in a lab study of the oxytocin receptor gene (OXTR), alcohol exposure, and aggression.

    PubMed

    LoParo, Devon; Johansson, Ada; Walum, Hasse; Westberg, Lars; Santtila, Pekka; Waldman, Irwin

    2016-07-01

    Naturalistic studies of gene-environment interactions (G X E) have been plagued by several limitations, including difficulty isolating specific environmental risk factors from other correlated aspects of the environment, gene-environment correlation (rGE ), and the use of a single genetic variant to represent the influence of a gene. We present results from 235 Finnish young men in two lab studies of aggression and alcohol challenge that attempt to redress these limitations of the extant G X E literature. Specifically, we use a latent variable modeling approach in an attempt to more fully account for genetic variation across the oxytocin receptor gene (OXTR) and to robustly test its main effects on aggression and its interaction with alcohol exposure. We also modeled aggression as a latent variable comprising various indices, including the average and maximum levels of aggression, the earliest trial on which aggression was expressed, and the proportion of trials on which the minimum and maximum levels of aggression were expressed. The best fitting model for the genetic variation across OXTR included six factors derived from an exploratory factor analysis, roughly corresponding to six haplotype blocks. Aggression levels were higher on trials in which participants were administered alcohol, won, or were provoked. There was a significant main effect of OXTR on aggression across studies after controlling for covariates. The interaction of OXTR and alcohol was also significant across studies, such that OXTR had stronger effects on aggression in the alcohol administration condition. © 2015 Wiley Periodicals, Inc. © 2015 Wiley Periodicals, Inc.

  10. Manipulation of colony environment modulates honey bee aggression and brain gene expression.

    PubMed

    Rittschof, C C; Robinson, G E

    2013-11-01

    The social environment plays an essential role in shaping behavior for most animals. Social effects on behavior are often linked to changes in brain gene expression. In the honey bee (Apis mellifera L.), social modulation of individual aggression allows colonies to adjust the intensity with which they defend their hive in response to predation threat. Previous research has showed social effects on both aggression and aggression-related brain gene expression in honey bees, caused by alarm pheromone and unknown factors related to colony genotype. For example, some bees from less aggressive genetic stock reared in colonies with genetic predispositions toward increased aggression show both increased aggression and more aggressive-like brain gene expression profiles. We tested the hypothesis that exposure to a colony environment influenced by high levels of predation threat results in increased aggression and aggressive-like gene expression patterns in individual bees. We assessed gene expression using four marker genes. Experimentally induced predation threats modified behavior, but the effect was opposite of our predictions: disturbed colonies showed decreased aggression. Disturbed colonies also decreased foraging activity, suggesting that they did not habituate to threats; other explanations for this finding are discussed. Bees in disturbed colonies also showed changes in brain gene expression, some of which paralleled behavioral findings. These results show that bee aggression and associated molecular processes are subject to complex social influences. © 2013 John Wiley & Sons Ltd and International Behavioural and Neural Genetics Society.

  11. Characterization of newly synthesized pyrimidine derivatives for corrosion inhibition as inferred from computational chemical analysis

    NASA Astrophysics Data System (ADS)

    El-Taib Heakal, F.; Rizk, S. A.; Elkholy, A. E.

    2018-01-01

    Corrosion of metallic constructions is a serious problem in most industries worldwide that can be controlled via addition of special chemicals having adsorption capability on metal surfaces and hence isolating it from the aggressive environment. These chemicals are characterized by being rich in functional groups containing free lone pairs of electrons and/or π-electrons. In the present study four newly imidazole-pyrimidine based ionic derivatives have been synthesized and their structures were characterized by means of elemental analysis and different spectroscopic techniques. Quantum chemical calculations were carried out to give insights into the structural and electronic characteristics of these fabricated compounds. Monte Carlo simulation was also applied to shed the light on our prepared corrosion inhibitor molecules by examining their aptitude to adsorb on iron surface. Our ultimate goal is to help industries in fighting corrosion by providing them with a cheap and efficient anti-corrosion molecules.

  12. Testing Silica Fume-Based Concrete Composites under Chemical and Microbiological Sulfate Attacks

    PubMed Central

    Estokova, Adriana; Kovalcikova, Martina; Luptakova, Alena; Prascakova, Maria

    2016-01-01

    Current design practices based on descriptive approaches to concrete specification may not be appropriate for the management of aggressive environments. In this study, the durability of cement-based materials with and without the addition of silica fume, subjected to conditions that leach calcium and silicon, were investigated. Chemical corrosion was simulated by employing various H2SO4 and MgSO4 solutions, and biological corrosion was simulated using Acidithiobacillus sp. bacterial inoculation, leading to disrupted and damaged surfaces; the samples’ mass changes were studied following both chemical and biological attacks. Different leaching trends were observed via X-ray fluorescence when comparing chemical with biological leaching. Lower leaching rates were found for concrete samples fortified with silica fume than those without silica fume. X-ray diffraction and scanning electron microscopy confirmed a massive sulfate precipitate formation on the concrete surface due to bacterial exposure. PMID:28773452

  13. Aggressive behaviour - prevention and management in the general practice environment.

    PubMed

    Sim, Moira G; Wain, Toni; Khong, Eric

    2011-11-01

    Aggressive behaviour is commonly encountered in the general practice setting and can often be de-escalated using good communication skills. This article provides strategies to reduce and manage early aggression in the general practice environment. Aggressive behaviour usually occurs when a person feels unfairly treated. Having a systematic approach to the problem can improve safety for both staff and patients. This includes patient centred practice, identifying and managing the early signs of aggression to prevent escalation, having a plan to seek assistance if required, setting limits using a calm respectful manner and reinforcing limits using behaviour contracts when required. The physical layout of the practice and restraint of aggressive people are beyond the scope of this article.

  14. [Gender differences of the influence of an "aggressive" computer game on the variability of the heart rhythm].

    PubMed

    Stepanian, L S; Grigorian, V G; Stepanian, A Iu

    2010-01-01

    The influence of virtual aggressogenic environment on psychoemotional sphere of male and female teenagers with different levels of personal aggression was studied by characteristics of the heart rate. The exposure to the aggressogenic factors produced a change of the centralized control for the autonomic control in female and male teenagers with the high level of aggression and females with the low level of aggression. Male teenagers with the low level of aggression displayed the prevalence of the centralized control. Thus, the influence of exposure of teenagers to the virtual aggressogenic environment was shown to be ambiguous depending on the level of the level of personal aggression and gender.

  15. Adolescent bystanders' perspectives of aggression in the online versus school environments.

    PubMed

    Patterson, Lisa J; Allan, Alfred; Cross, Donna

    2016-06-01

    Researchers' understanding of bystanders' perspectives in the cyber-environment fails to take young people's perceptions into account and remains imperfect. Interventions encouraging adolescents to help targets of cyber-aggression are therefore typically based upon traditional school-based aggression research. Twenty-four in-depth interviews with Australian 13-16 year-olds revealed two themes that reflect how young bystanders perceive differences between aggression online and at school. The physical presence theme suggests that young bystanders struggle to determine online intentions in the absence of body language, leading to hesitancy in reactions and furthermore make it easier for them to ignore online transgressions and avoid becoming involved. The authority theme indicates young bystanders perceive that, compared to the school environment, the online environment lacks clearly established rules, authority figures and formal reporting mechanisms. These differences indicate that unique strategies should be developed to encourage young bystanders to intervene in cyber-aggression situations. Copyright © 2016 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.

  16. The Role of Placement History and Current Family Environment in Children's Aggression in Foster Care.

    PubMed

    Perry, Kristin J; Price, Joseph

    2017-04-01

    Predictors of the physical and relational aggressive behavior of children in foster care were examined ( N = 160, 50.9% male, M age = 7.57, SD = 2.39). First, predictors representative of children's placement histories were examined in relation to the children's aggression at T1. Next, predictors representing characteristics of the current family environment were examined in relation to the children's aggression at T2 (four months later). Results revealed that a greater number of prior group home placements and being in a non-kinship home were associated with higher physical aggression at T1. A greater number of prior group home placements, a fewer number of regular home placements, being in a non-kinship home, and prior removal from the home due to neglect were associated with higher relational aggression at T1. The results also revealed that higher foster sibling relational aggression at T1 predicted lower child physical aggression at T2. If foster siblings were biological children of the foster parent, higher levels of a foster sibling's physical aggression at T1 predicted reduced child physical aggression at T2. The opposite pattern was observed if foster siblings were not biological children of the foster parent. Lastly, longer time in the current placement, more children in the home, and the presence of a sibling that was a biological child of the parent predicted higher child relational aggression at T2. These findings provide initial insights into how placement history and current family environment are associated with the physical and relational aggressive behavior of children in foster care.

  17. Managing aggression in the emergency department: promoting an interdisciplinary approach.

    PubMed

    Rintoul, Yvonne; Wynaden, Dianne; McGowan, Sunita

    2009-04-01

    Incidents of aggression are frequent occurrences in hospitals, particularly the emergency department. Aggression creates instability in the environment, impacts on patient care outcomes and leads to increased levels of stress in staff. Regular exposure to aggression in the workplace can have detrimental effects on health professionals' ongoing quality of life. The emergency department is a gateway to care and is heavily populated 24h a day. Therefore, it is essential that all health professionals are confident and well prepared to manage aggression. Based upon a review of the literature this paper outlines the causes of aggression and provides an interdisciplinary action plan for intervening with aggressive patients in the emergency department. The importance of interdisciplinary ownership and the well planned management of aggression are outlined. When well managed, the impact of aggression can be limited. Stability in the emergency department ensures that health professionals can be responsive to the community's needs for emergency care. This leads to the provision of effective and timely care and a stable work environment for all health professionals.

  18. Aggression in the work environment of physiotherapists.

    PubMed

    Szczegielniak, Anna; Skowronek, Anna; Krysta, Krzysztof; Krupka-Matuszczyk, Irena

    2012-09-01

    Aggression in the medical environment can take on different forms. It can be inflicted both by patients and workmates and may also cause a rise of aggressive behavior performed by the physiotherapists themselves. The aim of the study was to evaluate possible danger that may occur in the working environment of physiotherapists as well as to assess the correlation between such factors as the length of professional experience and exposure to the aggression inflicted by patients and workmates in the workplace with the level of aggression occurring within the professional group of physiotherapists. The study was conducted among 50 physiotherapists from Opole and the Silesian Voivodships in Poland. Two types of questionnaires were used: the author's own questionnaire, assessing exposure of the physiotherapists to aggression in the workplace, and the Buss-Perry Aggression Questionnaire. The results were analyzed with the Statistica 8.0 application. 60% of participants suffered from patients' verbal aggression, 8% from physical aggression and 26% from the patients' emotional self-aggression at least twice a month. The study showed a minor correlation between the duration of the length of professional experience and the level of hostility (r=0.2; p>0.05). There is a considerable impact of negative emotions present in relations with workmates at the workplace causing mainly increase of general aggression among physiotherapists and hostility. Similarly, negative emotions that may appear in relations between psychiatrists and patients show a positive correlation with the level of general aggression developed by doctors. It can be observed that there is a huge impact of the impulsive behaviour and attitude (presented both by patients and workmates in the workplaces) on the appearance of aggressive actions by physiotherapists (especially anger and hostility). Further research in this field is needed.

  19. Links between Friends' Physical Aggression and Adolescents' Physical Aggression: What Happens If Gene-Environment Correlations are Controlled?

    ERIC Educational Resources Information Center

    Vitaro, Frank; Brendgen, Mara; Girard, Alain; Dionne, Ginette; Tremblay, Richard E.; Boivin, Michel

    2016-01-01

    Exposure to deviant friends has been found to be a powerful source of influence on children's and adolescents' aggressive behavior. However, the contribution of deviant friends may have been overestimated because of a possible non-accounted gene-environment correlation (rGE). In this study, we used a cross-lagged design to test whether friends'…

  20. The Role of Placement History and Current Family Environment in Children’s Aggression in Foster Care

    PubMed Central

    Perry, Kristin J.; Price, Joseph

    2017-01-01

    Predictors of the physical and relational aggressive behavior of children in foster care were examined (N = 160, 50.9% male, M age = 7.57, SD = 2.39). First, predictors representative of children’s placement histories were examined in relation to the children’s aggression at T1. Next, predictors representing characteristics of the current family environment were examined in relation to the children’s aggression at T2 (four months later). Results revealed that a greater number of prior group home placements and being in a non-kinship home were associated with higher physical aggression at T1. A greater number of prior group home placements, a fewer number of regular home placements, being in a non-kinship home, and prior removal from the home due to neglect were associated with higher relational aggression at T1. The results also revealed that higher foster sibling relational aggression at T1 predicted lower child physical aggression at T2. If foster siblings were biological children of the foster parent, higher levels of a foster sibling’s physical aggression at T1 predicted reduced child physical aggression at T2. The opposite pattern was observed if foster siblings were not biological children of the foster parent. Lastly, longer time in the current placement, more children in the home, and the presence of a sibling that was a biological child of the parent predicted higher child relational aggression at T2. These findings provide initial insights into how placement history and current family environment are associated with the physical and relational aggressive behavior of children in foster care. PMID:29551877

  1. Family and social environmental factors associated with aggression among Chinese adolescents.

    PubMed

    Dou, Chunxia; Wei, Zhen; Jin, Ke; Wang, He; Wang, Xiulan; Peng, Ziwen

    2015-09-01

    Family and school environments are assumed to be associated with and influence aggressive behaviors. However, which specific risk factors within these environments that are associated with aggressive behavior are unclear. The goal of this study is to identify family and social environmental qualities that are related to aggression among Chinese adolescents. Survey data were obtained from 3,213 randomly selected urban high school students ages 10 through 18 in southern China. Lower parental attachment, higher family income, mother's higher education levels, father's parenting goals, rough or changeable parenting styles, unsuitable peer relationships, and inadequate social atmospheres at school serve as risk factors for aggression among Chinese adolescents. Our findings provide some implications for understanding aggression among adolescents and suggests possible interventions to help overcome potential environmental risk factors and thus to prevent aggressive behavior in school. (c) 2015 APA, all rights reserved).

  2. Gene-Gene-Environment Interactions of Serotonin Transporter, Monoamine Oxidase A and Childhood Maltreatment Predict Aggressive Behavior in Chinese Adolescents

    PubMed Central

    Zhang, Yun; Ming, Qing-sen; Yi, Jin-yao; Wang, Xiang; Chai, Qiao-lian; Yao, Shu-qiao

    2017-01-01

    Gene-environment interactions that moderate aggressive behavior have been identified independently in the serotonin transporter (5-HTT) gene and monoamine oxidase A gene (MAOA). The aim of the present study was to investigate epistasis interactions between MAOA-variable number tandem repeat (VNTR), 5-HTTlinked polymorphism (LPR) and child abuse and the effects of these on aggressive tendencies in a group of otherwise healthy adolescents. A group of 546 Chinese male adolescents completed the Child Trauma Questionnaire and Youth self-report of the Child Behavior Checklist. Buccal cells were collected for DNA analysis. The effects of childhood abuse, MAOA-VNTR, 5-HTTLPR genotypes and their interactive gene-gene-environmental effects on aggressive behavior were analyzed using a linear regression model. The effect of child maltreatment was significant, and a three-way interaction among MAOA-VNTR, 5-HTTLPR and sexual abuse (SA) relating to aggressive behaviors was identified. Chinese male adolescents with high expression of the MAOA-VNTR allele and 5-HTTLPR “SS” genotype exhibited the highest aggression tendencies with an increase in SA during childhood. The findings reported support aggression being a complex behavior involving the synergistic effects of gene-gene-environment interactions. PMID:28203149

  3. Localised corrosion in aluminium alloy 2024-T3 using in situ TEM.

    PubMed

    Malladi, Sairam; Shen, Chenggang; Xu, Qiang; de Kruijff, Tom; Yücelen, Emrah; Tichelaar, Frans; Zandbergen, Henny

    2013-11-28

    An approach to carry out chemical reactions using aggressive gases in situ in a transmission electron microscope (TEM), at ambient pressures of 1.5 bar using a windowed environmental cell, called a nanoreactor, is presented here. The nanoreactor coupled with a specially developed holder with platinum tubing permits the usage of aggressive chemicals like hydrochloric acid (HCl).

  4. Aggression Levels in College Students after Exposure or Non-Exposure to an Aggressive Life Experience.

    ERIC Educational Resources Information Center

    Pardeck, John T.; Nolden, Wesley L.

    1983-01-01

    Examined what types of aggressive behaviors are learned from an individual's social environment in a sample of 14 college students who were Vietnam veterans and 66 non-Vietnam veterans and nonveteran students. Results indicated assault is clearly one aggressive behavior that increases with exposure to aggressive life experience. (JAC)

  5. Should I fight or should I flight? How studying insect aggression can help integrated pest management.

    PubMed

    Benelli, Giovanni

    2015-07-01

    Aggression plays a key role all across the animal kingdom, as it allows the acquisition and/or defence of limited resources (food, mates and territories) in a huge number of species. A large part of our knowledge on aggressive behaviour has been developed on insects of economic importance. How can this knowledge be exploited to enhance integrated pest management? Here, I highlight how knowledge on intraspecific aggression can help IPM both in terms of insect pests (with a focus on the enhancement of the sterile insect technique) and in terms of biological control agents (with a focus on mass-rearing optimisation). Then, I examine what implications for IPM can be outlined from knowledge about interspecific aggressive behaviour. Besides predator-pest aggressive interactions predicted by classic biological control, I focus on what IPM can learn from (i) interspecific aggression among pest species (with special reference to competitive displacement), (ii) defensive behaviour exhibited by prey against predaceous insects and (iii) conflicts among predaceous arthropods sharing the same trophic niche (with special reference to learning/sensitisation practices and artificial manipulation of chemically mediated interactions). © 2015 Society of Chemical Industry.

  6. Fighting Nemo: Effect of 17α-ethinylestradiol (EE2) on aggressive behavior and social hierarchy of the false clown anemonefish Amphiprion ocellaris.

    PubMed

    Chen, Te-Hao; Hsieh, Chun-Yu

    2017-11-30

    Aggressive behavior is crucial for maintaining social hierarchy in anemonefish. Endocrine disrupting chemicals such as EE2 may affect fish social hierarchy via disrupting their aggression. In this study, we aimed to characterize the effects of 17α-ethinylestradiol (EE2) on aggressive behavior and social hierarchy in the false clown anemonefish (Amphiprion ocellaris). In the laboratory experiment, juvenile anemonefish were randomly distributed to separated tanks to form small colonies of three individuals and were fed with EE2-dosed diet (100ng/g food) or a control diet for 90d. Through the experiment, each tank was videotaped and behavioral indicators of social status, including aggressive behavior, submissive response, and shelter utilization, were quantitatively analyzed from the videos. The EE2 exposure caused a higher frequency of intra-colonial aggressive interactions and a less stable social hierarchy. Our findings demonstrate the importance of examining the effects of endocrine disrupting chemicals on the social behavior of coral reef fish. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. Spiny lobsters use urine-borne olfactory signaling and physical aggressive behaviors to influence social status of conspecifics.

    PubMed

    Shabani, Shkelzen; Kamio, Michiya; Derby, Charles D

    2009-08-01

    Decapod crustaceans, like many other animals, engage in agonistic behaviors that enhance their ability to compete for resources with conspecifics. These agonistic behaviors include the release of chemical signals as well as physical aggressive and submissive behaviors. In this study, we report that Caribbean spiny lobsters, Panulirus argus, use both urine-borne chemical signaling and physical aggressive behaviors during interactions with conspecifics, and that these agonistic behaviors can influence the behavior and eventual social status of the interactants. Spiny lobsters that engaged primarily in physical aggressive behaviors became dominant, whereas spiny lobsters that received these physical aggressive behaviors responded with avoidance behaviors and became subordinates. Dominant animals frequently released urine during social interactions, more than when they were not in contact with subordinates and more than when they were not paired with another animal. Subordinates released urine significantly less often than dominants, and no more than when not paired. Preventing release of urine by catheterizing the animals resulted in an increase in the number and duration of physical interactions, and this increase was primarily driven by dominants initiating interactions through physical aggressive behaviors. Introducing urine from one of the catheterized animals into an aquarium reduced physical aggressive behavior by dominant animals to normal levels. Urine-borne signals alone were capable of inducing avoidance behaviors from solitary spiny lobsters in both laboratory and field conditions. We conclude that urine serves as a chemical signal that communicates social status to the interactants. Ablation experiments showed that that these urine signals are detected primarily by aesthetasc sensilla of the olfactory pathway.

  8. Status Struggles: Network Centrality and Gender Segregation in Same- and Cross-Gender Aggression

    ERIC Educational Resources Information Center

    Faris, Robert; Felmlee, Diane

    2011-01-01

    Literature on aggression often suggests that individual deficiencies, such as social incompetence, psychological difficulties, or troublesome home environments, are responsible for aggressive behavior. In this article, by contrast, we examine aggression from a social network perspective, arguing that social network centrality, our primary measure…

  9. Genetic variation in social environment construction influences the development of aggressive behavior in Drosophila melanogaster

    PubMed Central

    Saltz, J B

    2017-01-01

    Individuals are not merely subject to their social environments; they choose and create them, through a process called social environment (or social niche) construction. When genotypes differ in social environment-constructing behaviors, different genotypes are expected to experience different social environments. As social experience often affects behavioral development, quantitative genetics and psychology theories predict that genetic variation in social environment construction should have an important role in determining phenotypic variation; however, this hypothesis has not been tested directly. I identify multiple mechanisms of social environment construction that differ among natural genotypes of Drosophila melanogaster and investigate their consequences for the development of aggressive behavior. Male genotypes differed in the group sizes that they preferred and in their aggressive behavior; both of these behaviors influenced social experience, demonstrating that these behaviors function as social environment-constructing traits. Further, the effects of social experience—as determined in part by social environment construction—carried over to affect focal male aggression at a later time and with a new opponent. These results provide manipulative experimental support for longstanding hypotheses in psychology, that genetic variation in social environment construction has a causal role in behavioral development. More broadly, these results imply that studies of the genetic basis of complex traits should be expanded to include mechanisms by which genetic variation shapes the environments that individuals experience. PMID:27848947

  10. Fine tuning of social integration by two myrmecophiles of the ponerine army ant, Leptogenys distinguenda.

    PubMed

    Witte, Volker; Foitzik, Susanne; Hashim, Rosli; Maschwitz, Ulrich; Schulz, Stefan

    2009-03-01

    Myrmecophiles are animals that live in close association with ants and that frequently develop elaborate mechanisms to infiltrate their well-defended host societies. We compare the social integration strategies of two myrmecophilic species, the spider, Gamasomorpha maschwitzi, and the newly described silverfish, Malayatelura ponerophila gen. n. sp. n., into colonies of the ponerine army ant, Leptogenys distinguenda (Emery) (Hymenoptera: Formicidae). Both symbionts use chemical mimicry through adoption of host cuticular hydrocarbons. Exchange experiments between L. distinguenda and an undetermined Leptogenys species demonstrate that reduced aggression toward alien ants and increased social acceptance occurred with individuals of higher chemical similarity in their cuticular hydrocarbon profiles. We found striking differences in chemical and behavioral strategies between the two myrmecophiles. Spider cuticular hydrocarbon profiles were chemically less similar to the host than silverfish profiles were. Nevertheless, spiders received significantly fewer attacks from host ants and survived longer in laboratory colonies, whereas silverfish were treated with high aggression and were killed more frequently. When discovered and confronted by the host, silverfish tended to escape and were chased aggressively, whereas spiders remained in contact with the confronting host ant until aggression ceased. Thus, spiders relied less on chemical mimicry but were nevertheless accepted more frequently by the host on the basis of behavioral mechanisms. These findings give insights into the fine tuning of social integration mechanisms and show the significance of qualitative differences among strategies.

  11. Efficacy of Chemical Mimicry by Aphid Predators Depends on Aphid-Learning by Ants.

    PubMed

    Hayashi, Masayuki; Nomura, Masashi; Nakamuta, Kiyoshi

    2016-03-01

    Chemical mimicry is an effective strategy when signal receivers recognize and discriminate models by relying on chemical cues. Some aphid enemies mimic the cuticular chemicals of aphids through various means thus avoiding detection and attack by aphid-tending ants. However, because ants have been reported to learn the chemical signatures of aphids in order to distinguish the aphids, the efficacy of chemical mimicry is predicted to depend on the experience of the ants that had tended aphids. The present study tested this hypothesis using two predator species: larvae of the green lacewing Mallada desjardinsi, and larvae of the ladybeetle Scymnus posticalis. Lacewing larvae carry the carcasses of aphids on which they have preyed upon their backs, and these function via chemical camouflage to reduce the aggressiveness of aphid-tending ants toward the larvae. Ladybeetle larvae reportedly produce a covering of wax structures, and their chemicals appear to attenuate ant aggression. We examined whether the behavior of the ant Tetramorium tsushimae toward these predators changed depending on their aphid-tending experience. Ants moderated their aggressiveness toward both predators when they had previously tended aphids, indicating that chemical mimicry by both aphid predators is dependent on previous experience of the ants in tending aphids. Chemical mimicry by the predators of ant-tended aphids is therefore considered to exploit learning-dependent aphid recognition systems of ants.

  12. Gender specific gene-environment interactions on laboratory-assessed aggression.

    PubMed

    Verona, Edelyn; Joiner, Thomas E; Johnson, Frank; Bender, Theodore W

    2006-01-01

    We examined gene-environment interactive effects on aggressive behavior among men and women genotyped (short versus long alleles) for the serotonin transporter gene. Aggressive behavior was indexed via a laboratory paradigm that measured the intensity and duration of shocks delivered to a putative "employee". Half of the participants were exposed to a physical stressor during the procedure (stress) and half were not (no-stress). Participants' physiological responses were gauged via acoustic startle eyeblink reactions (startle reactivity). Results were that men with the homozygous short (s/s) genotype showed increased aggression only under stress, whereas women and men carrying the long allele did not show differences in aggression in stress versus no-stress. However, although stress exposure produced increases in startle reactivity, there were no genotype or gender differences in physiology. These results replicate longitudinal research findings confirming the interactive effects of genes and environment on behavioral reactivity and on the development of externalizing psychopathological syndromes, at least in men.

  13. Role of motivation to respond to provocation, the social environment, and trait aggression in alcohol-related aggression.

    PubMed

    Tremblay, Paul F; Mihic, Ljiljana; Graham, Kathryn; Jelley, Jennifer

    2007-01-01

    Little attention has been paid to the motivation to respond to provocation and to the interaction between this motivation, alcohol, the drinking environment, and individual characteristics. Undergraduates at six Canadian universities (N = 1,232) read three vignettes describing conflict situations with social environmental manipulations while imagining themselves as either sober or intoxicated. Self-ratings assessed likelihood of assertive and aggressive responses and motivational indices of anger, offensiveness of the instigator's actions, and importance to respond to the provocation. Respondents also completed a measure of trait aggression. Multi-group structural equation models supported the hypothesis that perceived likelihood of reactive aggression is influenced by perceived alcohol intoxication, gender, trait aggression, social environmental factors, and motivation to respond to the provocation. In addition, a number of interactions were found among the predictors. These results provide insight into the types of factors that may influence aggression in drinking situations. Copyright 2007 Wiley-Liss, Inc.

  14. A systems modeling methodology for evaluation of vehicle aggressivity in the automotive accident environment

    DOT National Transportation Integrated Search

    2001-03-05

    A systems modeling approach is presented for assessment of harm in the automotive accident environment. The methodology is presented in general form and then applied to evaluate vehicle aggressivity in frontal crashes. The methodology consists of par...

  15. Hair and Salivary Testosterone, Hair Cortisol, and Externalizing Behaviors in Adolescents.

    PubMed

    Grotzinger, Andrew D; Mann, Frank D; Patterson, Megan W; Tackett, Jennifer L; Tucker-Drob, Elliot M; Harden, K Paige

    2018-05-01

    Although testosterone is associated with aggression in the popular imagination, previous research on the links between testosterone and human aggression has been inconsistent. This inconsistency might be because testosterone's effects on aggression depend on other moderators. In a large adolescent sample ( N = 984, of whom 460 provided hair samples), we examined associations between aggression and salivary testosterone, hair testosterone, and hair cortisol. Callous-unemotional traits, parental monitoring, and peer environment were examined as potential moderators of hormone-behavior associations. Salivary testosterone was not associated with aggression. Hair testosterone significantly predicted increased aggression, particularly at low levels of hair cortisol (i.e., Testosterone × Cortisol interaction). This study is the first to examine the relationship between hair hormones and externalizing behaviors and adds to the growing literature that indicates that androgenic effects on human behavior are contingent on aspects of the broader endocrine environment-in particular, levels of cortisol.

  16. Social Environmental Variation, Plasticity Genes, and Aggression: Evidence for the Differential Susceptibility Hypothesis

    PubMed Central

    Simons, Ronald L.; Lei, Man Kit; Beach, Steven R.H.; Brody, Gene H.; Philibert, Robert A.; Gibbons, Frederick X.

    2011-01-01

    Although G×E studies are typically based on the assumption that some individuals possess genetic variants that enhance their vulnerability to environmental adversity, the differential susceptibility perspective posits that these individuals are simply more susceptible to environmental influence than others. An important implication of this model is that those persons most vulnerable to adverse social environments are the same ones who reap the most benefit from environmental support. The present study tested several implications of this proposition. Using longitudinal data from a sample of several hundred African Americans, we found that relatively common variants of the dopamine receptor gene and the serotonin transporter gene interact with social environmental conditions to predict aggression in a manner consonant with differential susceptibility. When the social environment was adverse, individuals with these genetic variants manifested more aggression than other genotypes, whereas when the environment was supportive they demonstrated less aggression than other genotypes. Further, we found that these genetic variants interact with environmental conditions to foster various cognitive schemas and emotions in a manner consistent with differential susceptibility and that a latent construct formed by these schemas and emotions mediated the effect of gene by environment interaction on aggression. PMID:22199399

  17. Inattention/hyperactivity and aggression from early childhood to adolescence: heterogeneity of trajectories and differential influence of family environment characteristics.

    PubMed

    Jester, Jennifer M; Nigg, Joel T; Adams, Kenneth; Fitzgerald, Hiram E; Puttler, Leon I; Wong, Maria M; Zucker, Robert A

    2005-01-01

    Inattention/hyperactivity and aggressive behavior problems were measured in 335 children from school entry throughout adolescence, at 3-year intervals. Children were participants in a high-risk prospective study of substance use disorders and comorbid problems. A parallel process latent growth model found aggressive behavior decreasing throughout childhood and adolescence, whereas inattentive/hyperactive behavior levels were constant. Growth mixture modeling, in which developmental trajectories are statistically classified, found two classes for inattention/hyperactivity and two for aggressive behavior, resulting in a total of four trajectory classes. Different influences of the family environment predicted development of the two types of behavior problems when the other behavior problem was held constant. Lower emotional support and lower intellectual stimulation by the parents in early childhood predicted membership in the high problem class of inattention/hyperactivity when the trajectory of aggression was held constant. Conversely, conflict and lack of cohesiveness in the family environment predicted membership in a worse developmental trajectory of aggressive behavior when the inattention/hyperactivity trajectories were held constant. The implications of these findings for the development of inattention/hyperactivity and for the development of risk for the emergence of substance use disorders are discussed.

  18. Testosterone and Aggression.

    ERIC Educational Resources Information Center

    Archer, John

    1994-01-01

    Studies comparing aggressive and nonaggressive prisoners show higher testosterone levels among the former. While there is limited evidence for a strong association between aggressiveness and testosterone during adolescence, other studies indicate that testosterone levels are responsive to influences from the social environment, particularly those…

  19. To signal or not to signal? Chemical communication by urine-borne signals mirrors sexual conflict in crayfish

    PubMed Central

    2010-01-01

    Background Sexual selection theory predicts that females, being the limiting sex, invest less in courtship signals than males. However, when chemical signals are involved it is often the female that initiates mating by producing stimuli that inform about sex and/or receptivity. This apparent contradiction has been discussed in the literature as 'the female pheromone fallacy'. Because the release of chemical stimuli may not have evolved to elicit the male's courtship response, whether these female stimuli represent signals remains an open question. Using techniques to visualise and block release of urine, we studied the role of urine signals during fighting and mating interactions of crayfish (Pacifastacus leniusculus). Test individuals were blindfolded to exclude visual disturbance from dye release and artificial urine introduction. Results Staged female-male pairings during the reproductive season often resulted in male mating attempts. Blocking female urine release in such pairings prevented any male courtship behaviour. Artificial introduction of female urine re-established male mating attempts. Urine visualisation showed that female urine release coincides with aggressive behaviours but not with female submissive behaviour in reproductive interactions as well as in intersexual and intrasexual fights. In reproductive interactions, females predominately released urine during precopulatory aggression; males subsequently released significantly less urine during mating than in fights. Conclusions Urine-blocking experiments demonstrate that female urine contains sex-specific components that elicit male mating behaviour. The coincidence of chemical signalling and aggressive behaviour in both females and males suggests that urine release has evolved as an aggressive signal in both sexes of crayfish. By limiting urine release to aggressive behaviours in reproductive interactions females challenge their potential mating partners at the same time as they trigger a sexual response. These double messages should favour stronger males that are able to overcome the resistance of the female. We conclude that the difference between the sexes in disclosing urine-borne information reflects their conflicting interests in reproduction. Males discontinue aggressive urine signalling in order to increase their chances of mating. Females resume urine signalling in connection with aggressive behaviour, potentially repelling low quality or sexually inactive males while favouring reproduction with high quality males. PMID:20353555

  20. Aggression, Violence and Injury in Minor League Ice Hockey: Avenues for Prevention of Injury.

    PubMed

    Cusimano, Michael D; Ilie, Gabriela; Mullen, Sarah J; Pauley, Christopher R; Stulberg, Jennifer R; Topolovec-Vranic, Jane; Zhang, Stanley

    2016-01-01

    In North America, more than 800,000 youth are registered in organized ice hockey leagues. Despite the many benefits of involvement, young players are at significant risk for injury. Body-checking and aggressive play are associated with high frequency of game-related injury including concussion. We conducted a qualitative study to understand why youth ice hockey players engage in aggressive, injury-prone behaviours on the ice. Semi-structured interviews were conducted with 61 minor ice hockey participants, including male and female players, parents, coaches, trainers, managers and a game official. Players were aged 13-15 playing on competitive body checking teams or on non-body checking teams. Interviews were manually transcribed, coded and analyzed for themes relating to aggressive play in minor ice hockey. Parents, coaches, teammates and the media exert a large influence on player behavior. Aggressive behavior is often reinforced by the player's social environment and justified by players to demonstrate loyalty to teammates and especially injured teammates by seeking revenge particularly in competitive, body-checking leagues. Among female and male players in non-body checking organizations, aggressive play is not reinforced by the social environment. These findings are discussed within the framework of social identity theory and social learning theory, in order to understand players' need to seek revenge and how the social environment reinforces aggressive behaviors. This study provides a better understanding of the players' motivations and environmental influences around aggressive and violent play which may be conducive to injury. The findings can be used to help design interventions aimed at reducing aggression and related injuries sustained during ice hockey and sports with similar cultures and rules.

  1. Aggression, Violence and Injury in Minor League Ice Hockey: Avenues for Prevention of Injury

    PubMed Central

    Cusimano, Michael D.; Ilie, Gabriela; Mullen, Sarah J.; Pauley, Christopher R.; Stulberg, Jennifer R.; Topolovec-Vranic, Jane; Zhang, Stanley

    2016-01-01

    Background In North America, more than 800,000 youth are registered in organized ice hockey leagues. Despite the many benefits of involvement, young players are at significant risk for injury. Body-checking and aggressive play are associated with high frequency of game-related injury including concussion. We conducted a qualitative study to understand why youth ice hockey players engage in aggressive, injury-prone behaviours on the ice. Methods Semi-structured interviews were conducted with 61 minor ice hockey participants, including male and female players, parents, coaches, trainers, managers and a game official. Players were aged 13–15 playing on competitive body checking teams or on non-body checking teams. Interviews were manually transcribed, coded and analyzed for themes relating to aggressive play in minor ice hockey. Results Parents, coaches, teammates and the media exert a large influence on player behavior. Aggressive behavior is often reinforced by the player’s social environment and justified by players to demonstrate loyalty to teammates and especially injured teammates by seeking revenge particularly in competitive, body-checking leagues. Among female and male players in non-body checking organizations, aggressive play is not reinforced by the social environment. These findings are discussed within the framework of social identity theory and social learning theory, in order to understand players’ need to seek revenge and how the social environment reinforces aggressive behaviors. Conclusion This study provides a better understanding of the players’ motivations and environmental influences around aggressive and violent play which may be conducive to injury. The findings can be used to help design interventions aimed at reducing aggression and related injuries sustained during ice hockey and sports with similar cultures and rules. PMID:27258426

  2. MAOA genotype, social exclusion and aggression: an experimental test of a gene-environment interaction.

    PubMed

    Gallardo-Pujol, D; Andrés-Pueyo, A; Maydeu-Olivares, A

    2013-02-01

    In 2002, Caspi and colleagues provided the first epidemiological evidence that genotype may moderate individuals' responses to environmental determinants. However, in a correlational study great care must be taken to ensure the proper estimation of the causal relationship. Here, a randomized experiment was performed to test the hypothesis that the MAOA gene promoter polymorphism (MAOA-LPR) interacts with environmental adversity in determining aggressive behavior using laboratory analogs of real-life conditions. A sample of 57 Caucasian male students of Catalan and Spanish origin was recruited at the University of Barcelona. Ostracism, or social exclusion, was induced as environmental adversity using the Cyberball software. Laboratory aggression was assessed with the Point Subtraction Aggression Paradigm (PSAP), which was used as an analog of antisocial behavior. We also measured aggressiveness by means of the reduced version of the Aggression Questionnaire. The MAOA-LPR polymorphism showed a significant effect on the number of aggressive responses in the PSAP (F(1,53) = 4.63, P = 0.03, partial η(2) = 0.08), as well as social exclusion (F(1,53) = 8.03, P = 0.01, partial η(2) = 0.13). Most notably, however, we found that the MAOA-LPR polymorphism interacts significantly with social exclusion in order to provoke aggressive behavior (F(1,53) = 4.42, P = 0.04, partial η(2) = 0.08), remarkably, the low-activity allele of the MAOA-LPR polymorphism carriers in the ostracized group show significantly higher aggression scores than the rest. Our results support the notion that gene-environment interactions can be successfully reproduced within a laboratory using analogs and an appropriate design. We provide guidelines to test gene-environment interactions hypotheses under controlled, experimental settings. © 2012 The Authors. Genes, Brain and Behavior © 2012 Blackwell Publishing Ltd and International Behavioural and Neural Genetics Society.

  3. Effects of surgical and chemical sterilization on the behavior of free-roaming male dogs in Puerto Natales, Chile.

    PubMed

    Garde, E; Pérez, G E; Vanderstichel, R; Dalla Villa, P F; Serpell, J A

    2016-01-01

    Population management of free-roaming domestic dogs (Canis lupus familiaris) is of interest due to the threat these animals pose to people, other animals and the environment. Current sterilization procedures for male dogs include surgical and chemical methods. However, little is known about how these procedures affect their behavior. The primary objective of this study was to investigate changes in selected behaviors following chemical and surgical sterilization in a male free-roaming dog (FRD) population in southern Chile. We also examined the association between serum testosterone levels and behaviors thought to be influenced by circulating androgens. A total of 174 dogs were randomly assigned to either a surgical or chemical sterilization group, or a control group. At the onset of the intervention period, 119 dogs remained and 102 dogs successfully completed the study. Each dog was monitored pre- and post-intervention using video recordings, GPS collars, and blood samples for the measurement of testosterone. Analysis of behavior revealed that surgically castrated dogs showed no reduction of sexual activity or aggression when compared to their pre-intervention behavior. Chemically sterilized dogs showed a statistically significant increase in dog-directed aggression, but no change in sexual activity. There was no change in home range size in any groups between the pre- and post-intervention measurement. We found no consistent association between levels of serum testosterone concentration and behavioral changes in any of the groups. This study presents the first detailed behavioral observations following surgical and chemical sterilization in male FRDs. The information generated is highly relevant to communities struggling with the control of FRDs. Complementary studies to further our understanding of the effects of male sterilization on the behavioral and reproductive dynamics of FRD populations are needed. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. Corrosion Issues for Ceramics in Gas Turbines

    NASA Technical Reports Server (NTRS)

    Jacobson, Nathan; Opila, Elizabeth; Nickel, Klaus G.

    2004-01-01

    The requirements for hot-gas-path materials in gas turbine engines are demanding. These materials must maintain high strength and creep resistance in a particularly aggressive environment. A typical gas turbine environment involves high temperatures, rapid gas flow rates, high pressures, and a complex mixture of aggressive gases. Over the past forty years, a wealth of information on the behavior of ceramic materials in heat engine environments has been obtained. In the first part of the talk we summarize the behavior of monolithic SiC and Si3N4. These materials show excellent baseline behavior in clean, oxygen environments. However the aggressive components in a heat engine environment such as water vapor and salt deposits can be quite degrading. In the second part of the talk we discuss SiC-based composites. The critical issue with these materials is oxidation of the fiber coating. We conclude with a brief discussion of future directions in ceramic corrosion research.

  5. Inattention/hyperactivity and aggression from early childhood to adolescence: Heterogeneity of trajectories and differential influence of family environment characteristics

    PubMed Central

    JESTER, JENNIFER M.; NIGG, JOEL T.; ADAMS, KENNETH; FITZGERALD, HIRAM E.; PUTTLER, LEON I.; WONG, MARIA M.; ZUCKER, ROBERT A.

    2008-01-01

    In attention/hyperactivity and aggressive behavior problems were measured in 335 children from school entry throughout adolescence, at 3-year intervals. Children were participants in a high-risk prospective study of substance use disorders and comorbid problems. A parallel process latent growth model found aggressive behavior decreasing throughout childhood and adolescence, whereas inattentive/hyperactive behavior levels were constant. Growth mixture modeling, in which developmental trajectories are statistically classified, found two classes for inattention/hyperactivity and two for aggressive behavior, resulting in a total of four trajectory classes. Different influences of the family environment predicted development of the two types of behavior problems when the other behavior problem was held constant. Lower emotional support and lower intellectual stimulation by the parents in early childhood predicted membership in the high problem class of inattention/hyperactivity when the trajectory of aggression was held constant. Conversely, conflict and lack of cohesiveness in the family environment predicted membership in a worse developmental trajectory of aggressive behavior when the inattention/hyperactivity trajectories were held constant. The implications of these findings for the development of inattention/hyperactivity and for the development of risk for the emergence of substance use disorders are discussed. PMID:15971762

  6. Examining Holland's Person-Environment Fit, Workplace Aggression, Interpersonal Conflict, and Job Satisfaction

    ERIC Educational Resources Information Center

    Pseekos, A. Chantelle; Bullock-Yowell, Emily; Dahlen, Eric R.

    2011-01-01

    The researchers examined the impact of person-environment (P-E) fit, as defined by Holland's (1997) theory, on interpersonal conflict at work (ICAW) and workplace aggression. In addition, previous relationships found in the job satisfaction literature were examined in the present sample of 244 United States employees. Internet-based surveys were…

  7. Nurse managers: Determinants and behaviours in relation to patient and visitor aggression in general hospitals. A qualitative study.

    PubMed

    Heckemann, Birgit; Peter, Karin A; Halfens, Ruud Jg; Schols, Jos Mga; Kok, Gerjo; Hahn, Sabine

    2017-12-01

    To explore nurse managers' behaviours, attitudes, perceived social norms, and behavioural control in the prevention and management of patient and visitor aggression in general hospitals. Patient and visitor aggression in general hospitals is a global problem that incurs substantial human suffering and organizational cost. Managers are key persons for creating low-aggression environments, yet their role and behaviours in reducing patient and visitor aggression remains unexplored. A qualitative descriptive study underpinned by the Reasoned Action Approach. Between October 2015-January 2016, we conducted five focus groups and 13 individual interviews with nurse leaders in Switzerland. The semi-structured interviews and focus groups were recorded, transcribed, and analysed in a qualitative content analysis. We identified three main themes: (i) Background factors: "Patient and visitor aggression is perceived through different lenses"; (ii) Determinants and intention: "Good intentions competing with harsh organizational reality"; (iii) Behaviours: "Preventing and managing aggressive behaviour and relentlessly striving to create low-aggression work environments". Addressing patient and visitor aggression is difficult for nurse managers due to a lack of effective communication, organizational feedback loops, protocols, and procedures that connect the situational and organizational management of aggressive incidents. Furthermore, tackling aggression at an organizational level is a major challenge for nurse managers due to scant financial resources and lack of interest. Treating patient and visitor aggression as a business case may increase organizational awareness and interest. Furthermore, clear communication of expectations, needs and resources could optimize support provision for staff. © 2017 John Wiley & Sons Ltd.

  8. The Role of the School Environment in Relational Aggression and Victimization

    ERIC Educational Resources Information Center

    Elsaesser, Caitlin; Gorman-Smith, Deborah; Henry, David

    2013-01-01

    Research conducted over the last decade has documented both the high rates of and serious consequences associated with both victimization and perpetration of relational aggression. This study examines risk for involvement in relational aggression and victimization among middle school youth, evaluating both individual beliefs about violence, as…

  9. Moderating Effects of Autism on Parent Views of Genetic Screening for Aggression

    ERIC Educational Resources Information Center

    May, Michael E.; Brandt, Rachel C.; Bohannan, Joseph K.

    2012-01-01

    Advances in gene-environment interaction research have revealed genes that are associated with aggression. However, little is known about parent perceptions of genetic screening for behavioral symptoms like aggression as opposed to diagnosing disabilities. These perceptions may influence future research endeavors involving genetic linkage studies…

  10. Attracting predators without falling prey: chemical camouflage protects honeydew-producing treehoppers from ant predation.

    PubMed

    Silveira, Henrique C P; Oliveira, Paulo S; Trigo, José R

    2010-02-01

    Predaceous ants are dominant organisms on foliage and represent a constant threat to herbivorous insects. The honeydew of sap-feeding hemipterans has been suggested to appease aggressive ants, which then begin tending activities. Here, we manipulated the cuticular chemical profiles of freeze-dried insect prey to show that chemical background matching with the host plant protects Guayaquila xiphias treehoppers against predaceous Camponotus crassus ants, regardless of honeydew supply. Ant predation is increased when treehoppers are transferred to a nonhost plant with which they have low chemical similarity. Palatable moth larvae manipulated to match the chemical background of Guayaquila's host plant attracted lower numbers of predatory ants than unchanged controls. Although aggressive tending ants can protect honeydew-producing hemipterans from natural enemies, they may prey on the trophobionts under shortage of alternative food resources. Thus chemical camouflage in G. xiphias allows the trophobiont to attract predaceous bodyguards at reduced risk of falling prey itself.

  11. Aggression and feeding of hatchery-reared and naturally reared steelhead (Oncorhynchus mykiss) fry in a laboratory flume and a comparison with observations in natural streams

    USGS Publications Warehouse

    Riley, S.C.; Tatara, C.P.; Scheurer, J.A.

    2005-01-01

    We quantified the aggression and feeding of naturally reared steelhead (Oncorhynchus mykiss) fry stocked into a laboratory flume with naturally reared fry or hatchery-reared fry from conventional and enriched rearing environments at three densities in the presence and absence of predators, and compared the aggression and feeding observed in the flume to that observed in two streams. Steelhead fry attack rate increased with density and was reduced in the presence of predators, but was not affected by rearing treatment. Threat rate appeared to increase with density and was significantly affected by rearing treatment combination, but was not significantly affected by predator presence. Feeding rate was not affected by density or rearing treatment, but was reduced in the presence of predators. The rate of aggression by steelhead fry in two streams was lower than that observed in the laboratory and did not increase with density. Rates of aggression and feeding of hatchery-reared and wild steelhead fry were not significantly different in the streams. Overall, we found no evidence that hatchery rearing environments caused higher aggression in steelhead fry. Laboratory observations of salmonid aggression, particularly at high density, may not reflect aggression levels in the wild. ?? 2005 NRC.

  12. Environmental enrichment in steelhead (Oncorhynchus mykiss) hatcheries: Field evaluation of aggression, foraging, and territoriality in natural and hatchery fry

    USGS Publications Warehouse

    Tatara, C.P.; Riley, S.C.; Scheurer, J.A.

    2008-01-01

    Reforms for salmonid hatcheries include production of hatchery fish with behavioral characteristics similar to wild conspecifics. Enrichment of the hatchery environment has been proposed to achieve this goal. Field experiments of steelhead (i.e., sea-run rainbow trout, Oncorhynchus mykiss) fry from a common stock reared under natural (i.e., stream), enriched hatchery, and conventional hatchery conditions indicated no significant differences in the rates of foraging or aggression between rearing treatments. However, the rates of foraging and aggression of natural fry were significantly affected by the type of hatchery fry stocked with them. Natural steelhead fry fed at lower rates and exhibited higher rates of aggression when stocked with steelhead fry raised in enriched hatchery environments. Territory sizes of steelhead fry ranged from 0.015 to 0.801 m2; were significantly, positively related to body length; and were not significantly different between rearing treatments. We conclude that hatchery steelhead fry released into streams establish territories that are proportional to their body length and similar in size to territories of natural steelhead fry. Our results indicate that both conventional and enriched hatchery environments produce natural social behaviors in steelhead released as fry and that fry from enriched hatchery environments may alter the foraging and aggressive behavior of natural, resident steelhead fry. ?? 2008 NRC.

  13. Songbird chemical signals reflect uropygial gland androgen sensitivity and predict aggression: implications for the role of the periphery in chemosignaling.

    PubMed

    Whittaker, Danielle J; Rosvall, Kimberly A; Slowinski, Samuel P; Soini, Helena A; Novotny, Milos V; Ketterson, Ellen D

    2018-01-01

    Chemical signals can provide useful information to potential mates and rivals. The production mechanisms of these signals are poorly understood in birds, despite emerging evidence that volatile compounds from preen oil may serve as chemosignals. Steroid hormones, including testosterone (T), may influence the production of these signals, yet variation in circulating T only partly accounts for this variation. We hypothesized that odor is a T-mediated signal of an individual's phenotype, regulated in part by androgen sensitivity in the uropygial gland. We quantified natural variation in chemosignals, T, uropygial gland androgen sensitivity, and aggressive behavior in dark-eyed juncos (Junco hyemalis). The interaction between circulating T and androgen receptor transcript abundance significantly correlated with volatile concentrations in male, but not female, preen oil. In both sexes, odorant variables correlated with aggressive response to an intruder. Our results suggest that preen oil volatiles could function as signals of aggressive intent, and, at least in males, may be regulated by local androgen receptor signaling in the uropygial gland. Because these behavioral and chemical traits have been linked with reproductive success, local regulation of androgen sensitivity in the periphery has the potential to be a target of selection in the evolution of avian olfactory signaling.

  14. Means of atmospheric air pollution reduction during drilling wells

    NASA Astrophysics Data System (ADS)

    Shkitsa, L.; Yatsyshyn, T.; Lyakh, M.; Sydorenko, O.

    2016-08-01

    The process of drilling oil and gas wells is the source of air pollution through drilling mud evaporation containing hazardous chemical substances. The constructive solution for cleaning device of downhole tool that contains elements covering tube and clean the surface from the mud in the process of rising from the well is offered. Inside the device is filled with magnetic fluid containing the substance neutralizing hazardous substances. The use of the equipment proposed will make it possible to avoid penetration of harmful substances into the environment and to escape the harmful effects of aggressive substances for staff health and increase rig's fire safety.

  15. Tribochemical wear of single crystal aluminum in NaCl solution studied by atomic force microscopy

    NASA Astrophysics Data System (ADS)

    Cai, M.; Langford, S. C.; Dickinson, J. T.

    2011-09-01

    We report a systematic study of chemically enhanced wear of single crystal aluminum surfaces in aqueous solutions using an environmentally equipped atomic force microscope (AFM). The experiments were conducted by using a standard Si3N4 AFM tip to apply a localized force on a polished, single crystal aluminum (110) surface. Most measurements were performed in 0.5 M NaCl solution. We show the effect of applied force, number of scans, chemical solution, and temperature on the chemical-mechanical wear of aluminum on the nanometer scale. Aggressive chemical environments significantly enhance the wear of aluminum relative to scanning in dry air. Quantitative measurements show that the wear volume increases in proportion to the square root of force and the number of scans (or time). Arrhenius plots of wear volume versus temperature are consistent with an activation energy of 31 kJ/mol for scanning in 0.5 M NaCl. The wear of the AFM tip and the aluminum substrate is explained in terms of the synergistic surface chemical reactions and mechanical action of the tip. We compare these results to previous studies of AFM wear of silicate glass.

  16. Seven-year-olds' aggressive choices in a computer game can be predicted in infancy.

    PubMed

    Hay, Dale F; Johansen, Mark K; Daly, Peter; Hashmi, Salim; Robinson, Charlotte; Collishaw, Stephan; van Goozen, Stephanie

    2018-05-01

    Concerns about the relationship between computer games and children's aggression have been expressed for decades, but it is not yet clear whether the content of such games evokes aggression or a prior history of aggression promotes children's interest in aggressive games. Two hundred and sixty-six 7-year-old children from a nationally representative longitudinal sample in the UK played a novel computer game (CAMGAME) in which the child's avatar encountered a series of social challenges that might evoke aggressive, prosocial or neutral behaviour. Aggressive choices during the game were predicted by well-known risk factors for aggressive conduct problems and the children's own early angry aggressiveness as infants. These findings suggest that children who are predisposed to aggression bring those tendencies to virtual as well as real environments. © 2017 The Authors. Developmental Science Published by John Wiley & Sons Ltd.

  17. Service users’ experiences and views of aggressive situations in mental health care: a systematic review and thematic synthesis of qualitative studies

    PubMed Central

    Gudde, Camilla Buch; Olsø, Turid Møller; Whittington, Richard; Vatne, Solfrid

    2015-01-01

    Background Aggressive situations occurring within mental health services can harm service users, staff, and the therapeutic environment. There is a consensus that the aggression phenomenon is multidimensional, but the picture is still unclear concerning the complex interplay of causal variables and their respective impact. To date, only a small number of empirical studies include users’ views of relevant factors. The main objective of this review is to identify and synthesize evidence relating to service users’ experiences and views of aggressive situations in mental health settings. Methods We included qualitative studies of any design reporting on service users’ own experiences of conditions contributing to aggressive situations in mental health care and their views on preventative strategies. Eligible articles were identified through an electronic database search (PsycINFO, PubMed, Ovid Nursing Database, Embase, and CINAHL), hand search, and cross-referencing. Extracted data were combined and interpreted using aspects of thematic synthesis. Results We reviewed 5,566 records and included 13 studies (ten qualitative and three mixed methods). Service users recognized that both their own mental state and negative aspects of the treatment environment affected the development of aggressive situations. Themes were derived from experiential knowledge and included calls to be involved in questions regarding how to define aggression and relevant triggers, and how to prevent aggressive encounters effectively. The findings suggest that incidents are triggered when users experience staff behavior as custodial rather than caring and when they feel ignored. Conclusion The findings highlight the importance of staffs’ knowledge and skills in communication for developing relationships based on sensitivity, respect, and collaboration with service users in order to prevent aggressive situations. An important factor is a treatment environment with opportunities for meaningful activities and a preponderance of trained staff who work continuously on the development of conditions and skills for collaborative interaction with users. PMID:26491343

  18. Service users' experiences and views of aggressive situations in mental health care: a systematic review and thematic synthesis of qualitative studies.

    PubMed

    Gudde, Camilla Buch; Olsø, Turid Møller; Whittington, Richard; Vatne, Solfrid

    2015-01-01

    Aggressive situations occurring within mental health services can harm service users, staff, and the therapeutic environment. There is a consensus that the aggression phenomenon is multidimensional, but the picture is still unclear concerning the complex interplay of causal variables and their respective impact. To date, only a small number of empirical studies include users' views of relevant factors. The main objective of this review is to identify and synthesize evidence relating to service users' experiences and views of aggressive situations in mental health settings. We included qualitative studies of any design reporting on service users' own experiences of conditions contributing to aggressive situations in mental health care and their views on preventative strategies. Eligible articles were identified through an electronic database search (PsycINFO, PubMed, Ovid Nursing Database, Embase, and CINAHL), hand search, and cross-referencing. Extracted data were combined and interpreted using aspects of thematic synthesis. We reviewed 5,566 records and included 13 studies (ten qualitative and three mixed methods). Service users recognized that both their own mental state and negative aspects of the treatment environment affected the development of aggressive situations. Themes were derived from experiential knowledge and included calls to be involved in questions regarding how to define aggression and relevant triggers, and how to prevent aggressive encounters effectively. The findings suggest that incidents are triggered when users experience staff behavior as custodial rather than caring and when they feel ignored. The findings highlight the importance of staffs' knowledge and skills in communication for developing relationships based on sensitivity, respect, and collaboration with service users in order to prevent aggressive situations. An important factor is a treatment environment with opportunities for meaningful activities and a preponderance of trained staff who work continuously on the development of conditions and skills for collaborative interaction with users.

  19. Aggression in Primary Schools: The Predictive Power of the School and Home Environment

    ERIC Educational Resources Information Center

    Kozina, Ana

    2015-01-01

    In this study, we analyse the predictive power of home and school environment-related factors for determining pupils' aggression. The multiple regression analyses are performed for fourth- and eighth-grade pupils based on the Trends in Mathematics and Science Study (TIMSS) 2007 (N = 8394) and TIMSS 2011 (N = 9415) databases for Slovenia. At the…

  20. Aggressive and Violent Behaviors in the School Environment among a Nationally Representative Sample of Adolescent Youth

    ERIC Educational Resources Information Center

    Rajan, Sonali; Namdar, Rachel; Ruggles, Kelly V.

    2015-01-01

    Background: The purpose of this study was to describe the prevalence of aggressive and violent behaviors in the context of the school environment in a nationally representative sample of adolescent youth and to illustrate these patterns during 2001-2011. Methods: We analyzed data from 84,734 participants via the Youth Risk Behavior Surveillance…

  1. Teacher and Staff Perceptions of School Environment as Predictors of Student Aggression, Victimization, and Willingness to Intervene in Bullying Situations

    ERIC Educational Resources Information Center

    Espelage, Dorothy L.; Polanin, Joshua R.; Low, Sabina K.

    2014-01-01

    This study examines how teacher and staff perceptions of the school environment correlate with student self-reports of bullying, aggression, victimization, and willingness to intervene in bullying incidents using multi-informant, multilevel modeling. Data were derived from 3,616 6th grade students across 36 middle schools in the Midwest, who…

  2. The role of serotonin in impulsive aggression, suicide, and homicide in adolescents and adults: a literature review.

    PubMed

    Glick, Amy R

    2015-05-01

    This is a literature review discussing previous studies on the associations between impulsive aggression and the serotonergic system in adults, adolescents, and children. The review demonstrates that there is a clear association between low cerebrospinal fluid serotonin and impulsive aggression. However, studies on neurotransmitter receptor profiles, functional imaging, genetics, and epigenetics reviewed in this article suggest a more complicated picture that includes consideration of gene vs. environment in the evaluation of risk. Serotonin supplementation studies suggest that selective serotonin reuptake inhibitors may reduce impulsive aggression in some adults but are less effective in adults with pathological aggression and also in children and adolescents. Child and adolescent studies are less conclusive, in part due to the heterogeneous physiologic and psychosocial changes occurring over the course of development. The author thus concludes that psychiatrists can reduce risk in these special patient populations by creating safer environments in the form of changes in policy and increased support services.

  3. Monoamine Oxidase A (MAOA) and Catechol-O-Methyltransferase (COMT) Gene Polymorphisms Interact with Maternal Parenting in Association with Adolescent Reactive Aggression but not Proactive Aggression: Evidence of Differential Susceptibility.

    PubMed

    Zhang, Wenxin; Cao, Cong; Wang, Meiping; Ji, Linqin; Cao, Yanmiao

    2016-04-01

    To date, whether and how gene-environment (G × E) interactions operate differently across distinct subtypes of aggression remains untested. More recently, in contrast with the diathesis-stress hypothesis, an alternative hypothesis of differential susceptibility proposes that individuals could be differentially susceptible to environments depending on their genotypes in a "for better and for worse" manner. The current study examined interactions between monoamine oxidase A (MAOA) T941G and catechol-O-methyltransferase (COMT) Val158Met polymorphisms with maternal parenting on two types of aggression: reactive and proactive. Moreover, whether these potential G × E interactions would be consistent with the diathesis-stress versus the differential susceptibility hypothesis was tested. Within the sample of 1399 Chinese Han adolescents (47.2 % girls, M age = 12.32 years, SD = 0.50), MAOA and COMT genes both interacted with positive parenting in their associations with reactive but not proactive aggression. Adolescents with T alleles/TT homozygotes of MAOA gene or Met alleles of COMT gene exhibited more reactive aggression when exposed to low positive parenting, but less reactive aggression when exposed to high positive parenting. These findings provide the first evidence for distinct G × E interaction effects on reactive versus proactive aggression and lend further support for the differential susceptibility hypothesis.

  4. Human Aggression Across the Lifespan: Genetic Propensities and Environmental Moderators

    PubMed Central

    Tuvblad, Catherine; Baker, Laura A.

    2013-01-01

    This chapter reviews the recent evidence of genetic and environmental influences on human aggression. Findings from a large selection of the twin and adoption studies that have investigated the genetic and environmental architecture of aggressive behavior are summarized. These studies together show that about half (50%) of the variance in aggressive behavior is explained by genetic influences in both males and females, with the remaining 50% of the variance being explained by environmental factors not shared by family members. Form of aggression (reactive, proactive, direct/physical, indirect/relational), method of assessment (laboratory observation, self-report, ratings by parents and teachers), and age of the subjects—all seem to be significant moderators of the magnitude of genetic and environmental influences on aggressive behavior. Neither study design (twin vs. sibling adoption design) nor sex (male vs. female) seems to impact the magnitude of the genetic and environmental influences on aggression. There is also some evidence of gene-environment interaction (G × E) from both twin/adoption studies and molecular genetic studies. Various measures of family adversity and social disadvantage have been found to moderate genetic influences on aggressive behavior. Findings from these G × E studies suggest that not all individuals will be affected to the same degree by experiences and exposures, and that genetic predispositions may have different effects depending on the environment. PMID:22078481

  5. Examining Genetic and Environmental Effects on Reactive versus Proactive Aggression

    ERIC Educational Resources Information Center

    Brendgen, Mara; Vitaro, Frank; Boivin, Michel; Dionne, Ginette; Perusse, Daniel

    2006-01-01

    This study compared the contribution of genes and environment to teacher-rated reactive and proactive aggression in 6-year-old twin pairs (172 pairs: 55 monozygotic girls, 48 monozygotic boys, 33 dizygotic girls, 36 dizygotic boys). Genetic effects accounted for 39% of the variance of reactive aggression and for 41% of the variance of proactive…

  6. The effect of notches and pits on corrosion fatigue strength

    NASA Astrophysics Data System (ADS)

    Tatner, Ian

    An investigation has been undertaken to examine the fatigue behaviour of two martensitic steels in air and aggressive environments. The steels studied are, 18% Ni marageing steel and FV520B, the later being a stainless steel turbine blade material and the former being a marageing steel that suffers general corrosion in mild environments. Both steels were heat treated to give similar tensile strength.The design and manufacture of an autoclave allowed push-pull fatigue tests to be conducted in aggressive environments at elevated temperatures.Corrosion potential was monitored using a three electrode cell and was controlled during testing. Base-line fatigue tests were conducted with a range of constant corrosion potentials, using both notched and plain FV520B specimens. In addition fatigue tests with pulsed corrosion potential were performed to asses the effect of transient corrosion conditions on the corrosion fatigue strength. The pulsed tests were designed to simulate service transients in the oxygen content and general chemical hostility in the condensing steam environment during start-up and shut down of the steam turbine.Post test examination of fractured samples was performed using Scanning Electron Microscopy (SEM) and optical microscope techniques. The fractography results were used to quantify microstructural and fracture features of the steels.A model based on the size and geometry of the initial corrosion pitting has been proposed to asses the fatigue life of FV520B in an aggressive environment.The effect of pitting on the corrosion fatigue strength of FV520B has been modelled using linear elastic fracture mechanics (LEFM) type approach. The model has shown a good correlation between predicted fatigue lives with experimental results.The results suggest that the fatigue life is governed by the mechanical stress concentrating effect of the pits rather than the electrochemical damage caused by the environment.Finite Element Analysis (FEA) of the notch allowed calculation of the elastic stress intensity factor (K[t]) for the specimen geometry used. The experimental results together with numerical results of FEA were used to calculate of the notch strength reduction factor (K[f]) for the material. This has been used to derive the notch sensitivity factors (q) for both materials.The results of fatigue tests in air showed that although both materials have similar tensile strength their plain fatigue strengths are different. The sensitivity of the fatigue strength to notches was also found to be significantly different. The marageing steel showed a higher sensitivity to a notch than the FV520B.An empirical model has been proposed to quantify the notch sensitivity and the effects of various microstructural features on the fatigue strength. A model has been developed to predict the serviceable life of a peak hardened FV520B turbine blade subjected to aggressive low load conditions during start-up and non-aggressive high load conditions during continual running. The model is based on the conclusions suggested in the work of a threshold stress intensity factor being reached where a fatigue crack will grow from a corrosion pit at the root of a notch. The model is then used to highlight the life reduction caused to steam turbine blades due to increased numbers of start-up cycles.

  7. Redox sensitive Pyk2 as a target for therapeutics in breast cancer.

    PubMed

    Felty, Quentin

    2011-01-01

    Breast cancer progression is dependent on the formation of new blood vessels that not only help the tumor by supplying additional nutrients, but also allow cancer cells to spread from the breast to distant sites in the body. Several studies suggest a positive correlation between new vessel formation and estrogens. Estrogenic environmental chemicals such as PCBs have been shown to increase the expression of factors known to promote vessel formation in breast tumors. These studies highlight a growing concern that women exposed to estrogenic environmental compounds may be more susceptible to either aggressive metastatic tumors or a high recurrence of breast cancer. Our concept offers a fundamental new understanding of the way the environment contributes to breast cancer progression. This review will be focused on a highly novel Pyk2 signaling complex as a target for therapy of estrogen dependent breast tumor angiogenesis. A better understanding of the role of Pyk2 signaling in estrogen dependent tumor vascularization may lead to the development of a new therapy against aggressive breast cancer using small molecule inhibitors of Pyk2.

  8. Development of an aggressive bark beetle on novel hosts: Implications for outbreaks in an invaded range

    Treesearch

    Derek W. Rosenberger; Robert C. Venette; Brian H. Aukema; Jörg Müller

    2018-01-01

    Some subcortical insects have devastating effects on native tree communities in new ranges, despite benign interactions with their historical hosts. Examples of how insects, aggressive in their native habitat might respond in novel host environs are less common. One aggressive tree-killing insect undergoing a dramatic range shift is the mountain pine beetle (...

  9. Features of Social Attitudes and Value Orientations of Youths and Adolescents Prone to Auto-Aggressive Behavior

    ERIC Educational Resources Information Center

    Salakhova, Valentina B.; Oschepkov, Aleksey A.; Lipatova, Nadezda V.; Popov, Pavel V.; Mkrtumova, Irina V.

    2016-01-01

    The relevance of the study is due to the growth of social symptoms of aggression directed forwards the Self, which is especially visible in environment of young people. The presented article is aimed at research relations between value orientations and social attitudes among youths and adolescents prone to auto-aggressive behavior. The…

  10. Characteristics of aggression among psychiatric inpatients by ward type in Japan: Using the Staff Observation Aggression Scale - Revised (SOAS-R).

    PubMed

    Sato, Makiko; Noda, Toshie; Sugiyama, Naoya; Yoshihama, Fumihiro; Miyake, Michi; Ito, Hiroto

    2017-12-01

    Aggressive behaviour by psychiatric patients is a serious issue in clinical practice, and adequate management of such behaviour is required, with careful evaluation of the factors causing the aggression. To examine the characteristics of aggressive incidents by ward type, a cross-sectional descriptive study was conducted for 6 months between April 2012 and June 2013 using the Staff Observation Aggression Scale - Revised, Japanese version (SOAS-R) in 30 wards across 20 Japanese psychiatric hospitals. Participating wards were categorized into three types based on the Japanese medical reimbursement system: emergency psychiatric, acute psychiatric, and standard wards (common in Japan, mostly treating non-acute patients). On analyzing the 443 incidents reported, results showed significant differences in SOAS-R responses by ward type. In acute and emergency psychiatric wards, staff members were the most common target of aggression. In acute psychiatric wards, staff requiring patients to take medication was the most common provocation, and verbal aggression was the most commonly used means. In emergency psychiatric wards, victims felt threatened. In contrast, in standard wards, both the target and provocation of aggression were most commonly other patients, hands were used, victims reported experiencing physical pain, and seclusion was applied to stop their behaviour. These findings suggest that ward environment was an important factor influencing aggressive behaviour. Ensuring the quality and safety of psychiatric care requires understanding the characteristics of incidents that staff are likely to encounter in each ward type, as well as implementing efforts to deal with the incidents adequately and improve the treatment environment. © 2016 Australian College of Mental Health Nurses Inc.

  11. Aggression inoculates against PTSD symptom severity—insights from armed groups in the eastern DR Congo

    PubMed Central

    Hecker, Tobias; Hermenau, Katharin; Maedl, Anna; Schauer, Maggie; Elbert, Thomas

    2013-01-01

    Background In the ongoing conflict in the Democratic Republic of the Congo (DRC), combatants are exposed to massive forms of violence and other traumatic stressors. Nevertheless, many combatants do not suffer from trauma-related disorders, although they have experienced numerous traumatizing events. Perceiving aggressive behavior as fascinating and arousing might be a defense against trauma-related disorders in the violent environment of war and conflict. Objective Thus, in this study we investigated the relationship between the exposure to traumatic stressors, appetitive aggression, and posttraumatic stress disorder (PTSD) symptom severity. We hypothesized that cumulative traumatic experiences correlated positively and appetitive aggression negatively with PTSD symptom severity. Method In total, 105 voluntary male combatants from different armed groups in the eastern DRC took part in this study. In a semistructured interview, respondents were questioned about their exposure to traumatic stressors, the extent of appetitive aggression (Appetitive Aggression Scale) and their PTSD symptom severity (PTSD Symptom Scale - Interview). Results A multiple sequential regression analysis showed that traumatic events were positively related to PTSD symptom severity. For participants with low to medium PTSD symptom severity, appetitive aggression correlated negatively with PTSD symptom severity. Conclusions The results of this study provide further support for earlier findings that repeated exposure to traumatic stressors cumulatively heightens the risk of PTSD and revealed that appetitive aggression buffers the risk of developing PTSD symptoms under certain circumstances. Thus, the perception of aggressive behavior as fascinating and arousing seem to help combatants to adapt to violent environments but may also be one reason for recurrent failure of reintegration programs for excombatants. PMID:23671766

  12. Acute exposure to 17α-ethinylestradiol alters boldness behavioral syndrome in female Siamese fighting fish.

    PubMed

    Dzieweczynski, Teresa L; Campbell, Brennah A; Marks, Jodi M; Logan, Brittney

    2014-09-01

    The role of anthropogenic sources in generating, maintaining, and influencing behavioral syndromes has recently been identified as an important area of future research. Endocrine disrupting chemicals are prevalent and persistent in aquatic ecosystems worldwide. These chemicals are known to have marked effects on the morphology and behavior of exposed individuals and, as such, may serve as a potential influence on behavioral syndromes. However, both the effects of exposure on behaviors beyond courtship and aggression and how exposure might affect behavioral variation at the individual level are understudied. To address this question, we examined boldness behavior in female Siamese fighting fish in three different assays (Novel Environment, Empty Tank, Shoaling) both before and after they were exposed to the estrogen mimic, 17α-ethinylestradiol (EE2). EE2 influences courtship, aggression, and boldness in males of this species but its effects have not been examined in females, to our knowledge. Females were tested multiple times in each assay before and after exposure so that behavioral consistency could be examined. A behavioral syndrome for boldness and activity level occurred across the three assays. The reductions in boldness and loss of the behavioral syndrome that resulted from EE2 exposure were surprising and suggest that the effects of EE2 exposure on female behavior and physiology should be examined more frequently. This study is one of the first to examine the effects of EE2 in females as well as on correlated behaviors and emphasizes the importance of examining the effects of endocrine disrupting chemicals on individual behavioral variation and consistency. Copyright © 2014 Elsevier Inc. All rights reserved.

  13. Reductions in aggressive behavior within the context of a universal, social emotional learning program: Classroom- and student-level mechanisms.

    PubMed

    Portnow, Sam; Downer, Jason T; Brown, Joshua

    2018-06-01

    The present study uses data from 35 third through fifth-grade urban classrooms and 531 students to examine the extent to which student-level social and emotional skills (e.g., low hostile attribution bias and low aggressive interpersonal negotiation strategies) and emotionally supportive learning environments predict aggressive behavior over the course of a school year. Results of multiple regression analyses indicated that across teacher-reported measures of aggressive behavior, more classroom emotional support over the course of the school year predicted less aggressive behavior in spring, particularly for children whose hostile attribution bias decreased over the course of the year. According to a child-reported measure of aggressive behavior, declines in aggressive interpersonal negotiation strategies over the course of the year also predicted less aggressive behavior in spring. Moreover, these results operated similarly across all children. Implications for SEL programs are discussed. Published by Elsevier Ltd.

  14. The impact assessment of weight loss on an aggressive behavior and satisfaction with the connubial or cohabitation relationship in patients after Roux-en-Y gastric-by-pass surgery performed laparoscopically.

    PubMed

    Bielecka, Ilona; Osemek, Paweł; Paśnik, Krzysztof

    2012-09-01

    was an assesment the impact of weight loss in patients undergoing gastric by-pass surgery on an aggressive behavior affecting the satisfaction with the connubial or cohabitation relationship The study included a total number of 100 people (50 people with morbid obesity underwent gastric-bypass surgery and their male or female partners). The study was conducted by using two questionnaires: the Psychological Inventory of Aggression Syndrome-1 authorship by Z.B. Gaś as well as Extinguishes and the Chosen Marriage Questionnaire-2 developed by M. Plop and J. Rostowski The analysis of the results showed the influence of the weight loss on the aggressive behaviour at the examined group. Important differences were shown in the first phase of the examination among the examined group and the control group on scales: emotional self-aggression, the hostility towards surroundings and directed outside aggression. Regression analysis showed a statistical relationship between outward aggression and disappointment, 0.346 p<0.01, intimacy 0.943 p<0.01, and the result of general satisfaction with the relationship 0.832 p<0.05.While self-realization is negatively correlated with a displaced aggression -0.342 p<0.01 and the intermediate one -0.225 p<0.01. Hostility towards the environment correlates positively with intimacy 0.326 p<0.01. Indirect aggression correlates negatively with a disappointment -0.324 for p <0.05. Important differences were shown in the second stage of the examination among groups examined on the scale inspection of the aggressive behaviour. Substantial results weren't demonstrated on scales: emotional self-aggression, hostility towards the environment and directed outside aggression In the regression analysis we received a statistically significant result: controlling an aggressive behavior correlates negatively with disappointment -0, 355 p <0,01. However, no statistically significant results were received from the partners of obese people. Weight loss after gastric-by-pass surgery has the significant impact on the rarer occurrence of an aggressive behavior, which improving the quality of the connubial or cohabitation relationship.

  15. Estimation of the Driving Style Based on the Users' Activity and Environment Influence.

    PubMed

    Sysoev, Mikhail; Kos, Andrej; Guna, Jože; Pogačnik, Matevž

    2017-10-21

    New models and methods have been designed to predict the influence of the user's environment and activity information to the driving style in standard automotive environments. For these purposes, an experiment was conducted providing two types of analysis: (i) the evaluation of a self-assessment of the driving style; (ii) the prediction of aggressive driving style based on drivers' activity and environment parameters. Sixty seven h of driving data from 10 drivers were collected for analysis in this study. The new parameters used in the experiment are the car door opening and closing manner, which were applied to improve the prediction accuracy. An Android application called Sensoric was developed to collect low-level smartphone data about the users' activity. The driving style was predicted from the user's environment and activity data collected before driving. The prediction was tested against the actual driving style, calculated from objective driving data. The prediction has shown encouraging results, with precision values ranging from 0.727 up to 0.909 for aggressive driving recognition rate. The obtained results lend support to the hypothesis that user's environment and activity data could be used for the prediction of the aggressive driving style in advance, before the driving starts.

  16. Dementia care worker stress associations with unit type, resident, and work environment characteristics: a cross-sectional secondary data analysis of the Swiss Nursing Homes Human Resources Project (SHURP).

    PubMed

    Vogel, Barbara; De Geest, Sabina; Fierz, Katharina; Beckmann, Sonja; Zúñiga, Franziska

    2017-03-01

    Although caring for residents with dementia in nursing homes is associated with various stressors for care workers, the role of the unit type, and particularly the proportion of residents with dementia, remains unclear. This study aimed to explore associations between unit type and care worker stress, taking into account additional potential stressors. This cross-sectional study was a secondary data analysis in the Swiss Nursing Homes Human Resources Project, which included data from 3,922 care workers from 156 Swiss nursing homes. Care workers' stress was measured with a shortened version of the Health Professions Stress Inventory. Generalized estimating equation models were used to assess care worker stress and its relationships with three unit types (special care units and others with high or low proportions of residents with dementia), work environment factors, and aggressive resident behavior. After including all potential stressors in the models, no significant differences between the three unit types regarding care worker stress were found. However, increased care worker stress levels were significantly related to lower ratings of staffing and resources adequacy, the experience of verbal aggression, and the observation of verbal or physical aggression among residents. Although the unit type plays only a minor role regarding care worker stress, this study confirms that work environment and aggressive behavior of residents are important factors associated with work-related stress. To prevent increases of care worker stress, interventions to improve the work environment and strengthen care workers' ability to cope with aggressive behavior are suggested.

  17. Early Childhood Education Teachers' Strategies Use in Order to Prevent Aggressive Behaviors in Classes: The Case of Turkey

    ERIC Educational Resources Information Center

    Derman, Meral Taner

    2017-01-01

    The aim of this research is to investigate the aggression types observed in class environment in preschool and primary schools and the strategies that teachers use in order to prevent aggressive behaviors in classes by variables like gender, seniority and socioeconomic level. 118 preschool teachers and 176 primary school teachers, a total of 294…

  18. Physicochemical characterization of discrete weapons grade plutonium metal particles originating from the 1960 BOMARC incident

    NASA Astrophysics Data System (ADS)

    Bowen, James M.

    The goal of this research was to investigate the physicochemical properties of weapons grade plutonium particles originating from the 1960 BOMARC incident for the purpose of predicting their fate in the environment and to address radiation protection and nuclear security concerns. Methods were developed to locate and isolate the particles in order to characterize them. Physical, chemical, and radiological characterization was performed using a variety of techniques. And finally, the particles were subjected to a sequential extraction procedure, a series of increasingly aggressive reagents, to simulate an accelerated environmental exposure. A link between the morphology of the particles and their partitioning amongst environmental mechanisms was established.

  19. Social Context Influences Aggressive and Courtship Behavior in a Cichlid Fish

    PubMed Central

    Desjardins, Julie K.; Hofmann, Hans A.; Fernald, Russell D.

    2012-01-01

    Social interactions require knowledge of the environment and status of others, which can be acquired indirectly by observing the behavior of others. When being observed, animals can also alter their signals based on who is watching. Here we observed how male cichlid fish (Astatotilapia burtoni) behave when being watched in two different contexts. In the first, we show that aggressive and courtship behaviors displayed by subordinate males depends critically on whether dominant males can see them, and in the second, we manipulated who was watching aggressive interactions and showed that dominant males will change their behavior depending on audience composition. In both cases, when a more dominant individual is out of view and the audience consists of more subordinate individuals, those males signal key social information to females by displaying courtship and dominant behaviors. In contrast, when a dominant male is present, males cease both aggression and courtship. These data suggest that males are keenly aware of their social environment and modulate their aggressive and courtship behaviors strategically for reproductive and social advantage. PMID:22807996

  20. RETRACTED: Chemical densification of plasma sprayed yttria stabilized zirconia (YSZ) coatings for high temperature wear and corrosion resistance

    NASA Astrophysics Data System (ADS)

    Ye, Yaping; Fehr, Karl Thomas; Faulstich, Martin; Wolf, Gerhard

    2012-12-01

    Plasma-sprayed yttria stabilized zirconia (YSZ) ceramic coatings have been widely used as wear- and corrosion-resistant coatings in high temperature applications and an aggressive environment due to their high hardness, wear resistance, heat and chemical resistance, and low thermal conductivity. The highly porous structure of plasma-sprayed ceramic coatings and their poor adhesion to the substrate usually lead to the coating degradation and failure. In this study, a two-layer system consisting of atmospheric plasma-sprayed 8 wt.% yttria-stabilized zirconia (8YSZ) and Ni-based alloy coatings was post-treated by means of a novel chemical sealing process at moderate temperatures of 600-800 °C. Microstructure characteristics of the YSZ coatings were studied using an electron probe micro-analyzer (EPMA). Results revealed that the ceramic top coat was densified by the precipitated zirconia in the open pores. Therefore, the sealed YSZ coatings exhibit reduced porosity, higher hardness and a better adhesion onto the bond coat. The mechanisms for the sealing process were also proposed.

  1. Interstitial assessment of aggressive prostate cancer by physio-chemical photoacoustics: an ex vivo study with intact human prostates.

    PubMed

    Huang, Shengsong; Qin, Yu; Chen, Yingna; Pan, Jing; Xu, Chengdang; Wu, Denglong; Chao, Wan-Yu; Wei, John T; Tomlins, Scott A; Wang, Xueding; Brian Fowlkes, J; Carson, Paul L; Cheng, Qian; Xu, Guan

    2018-06-23

    Transrectal ultrasound (TRUS) guided biopsy is the standard procedure for evaluating the presence and aggressiveness of prostate cancer. TRUS biopsy involves tissue removal, and suffers from low core yield as well as high false negative rate. A less invasive and more accurate diagnostic procedure for prostate cancer is therefore highly desired. Combining the optical sensitivity and ultrasonic resolution to resolve the spatial distribution of the major molecular components in tissue, photoacoustic (PA) technology could be an alternative approach for the diagnosis of prostate cancer. The purpose of this study is to examine the feasibility of identifying aggressive prostate cancer using interstitial PA measurements. 17 patients with pre-biopsy magnetic resonance imaging (MRI), TRUS biopsies and planned prostatectomies were enrolled in this study. The interstitial PA measurements were achieved using our recently developed needle PA probe, which was inserted into the ex vivo prostates in the fashion of a biopsy needle. A total of 70 interstitial PA measurements were acquired. The PA measurements were quantified by a previously established PA physio-chemical analysis (PAPCA) method. The histology has confirmed the nonaggressive and aggressive cancerous conditions at the insertion locations. The diagnostic accuracy was also compared to that provided by the pre-biopsy MRI. The quantitative study shows significant differences between the individual parameters of the nonaggressive and the aggressive cancerous regions (p<0.005). Multivariate analysis of the quantitative features achieved a diagnostic accuracy of 78.6% for differentiating nonaggressive and aggressive prostate cancer tissues CONCLUSIONS: The proposed procedure has shown promises in the diagnosis of aggressive prostate cancer. This article is protected by copyright. All rights reserved.

  2. Feline aggression toward family members: a guide for practitioners.

    PubMed

    Bain, Melissa; Stelow, Elizabeth

    2014-05-01

    Feline aggression toward people is a common and potentially dangerous problem. Proper diagnosis of the underlying cause of the aggression is key in effective treatment. A complete history, including information on the people in the home, other pets, and specific incidents, is necessary to make this diagnosis. A comprehensive treatment plan typically includes management, enhancement of the cat's living environment, techniques for replacing the aggressive behavior with more appropriate behaviors, and, potentially, medication. The treatment plan must reflect the abilities and commitment of the owner. Copyright © 2014 Elsevier Inc. All rights reserved.

  3. Hydraulic permeability of bentonite-polymer composites for application in landfill technology

    NASA Astrophysics Data System (ADS)

    Dehn, Hanna; Haase, Hanna; Schanz, Tom

    2015-04-01

    Bentonites are often used as barrier materials in landfill technology to prevent infiltration of leachates to the natural environment. Since decades, geoenvironmental engineering aims at improving the hydro-mechanical performance of landfill liners. Various studies on the permeability performance of geosynthetic clay liners (GCLs) show effects of non-standard liquids on behaviour of Na+-bentonite regarding its sealing capacity. With increasing concentration of chemical aggressive solutions the sealing capacity decreases (Shackelford et al. 2000). An opportunity to improve the hydraulic permeability of the bentonites is the addition of polymers. The changes in hydraulic permeability performance of polymer treated and untreated bentonites while adding chemical aggressive solutions were studied by several authors. Results obtained by Scalia et al. (2014) illustrate that an increase in permeability can be prevented by adding polymer to Na+-bentonite. On the other hand, Ashmawy et al. (2002) presented results on the incapability of several commercial bentonite-polymer-products. The objective of this study is to characterize the influence of polymer addition on hydraulic performance of Na+-bentonite systematically. Therefore, the influence of 1% polymer addition of cationic and anionic polyacrylamide on the swelling pressure and hydraulic permeability of MX 80 bentonite was investigated. Preparation of bentonite-polymer composites was conducted (1) in dry conditions and (2) using solution-intercalation method. Experiments on hydraulic permeability were carried out using distilled water as well as CaCl2-solution. References Ashmawy, A. K., El-Hajji, D., Sotelo, N. & Muhammad, N. (2002), `Hydraulic Performance of Untreated and Polymer-treated Bentonite in Inorganic Landfill Leachates', Clays and Clay Minerals 50(5), 546-552. Scalia, J., Benson, C., Bohnhoff, G., Edil, T. & Shackelford, C. (2014), 'Long-Term Hydraulic Conductivity of a Bentonite-Polymer Composite Permeated with Aggressive Inorganic Solutions', Journal of Geotechnical and Geoenvironmental Engineering 140(3). Shackelford, C. D., Benson, C. H., Katsumi, T., Edil, T. B. & Lin, L. (2000), 'Evaluating the hydraulic conductivity of GCLs permeated with non-standard liquids', Geotextiles and Geomembranes 18, 133-161.

  4. Behavioural and chemical evidence for multiple colonisation of the Argentine ant, Linepithema humile, in the Western Cape, South Africa

    PubMed Central

    2011-01-01

    Background The Argentine ant, Linepithema humile, is a widespread invasive ant species that has successfully established in nearly all continents across the globe. Argentine ants are characterised by a social structure known as unicoloniality, where territorial boundaries between nests are absent and intraspecific aggression is rare. This is particularly pronounced in introduced populations and results in the formation of large and spatially expansive supercolonies. Although it is amongst the most well studied of invasive ants, very little work has been done on this ant in South Africa. In this first study, we investigate the population structure of Argentine ants in South Africa. We use behavioural (aggression tests) and chemical (CHC) approaches to investigate the population structure of Argentine ants within the Western Cape, identify the number of supercolonies and infer number of introductions. Results Both the aggression assays and chemical data revealed that the Western Cape Argentine ant population can be divided into two behaviourally and chemically distinct supercolonies. Intraspecific aggression was evident between the two supercolonies of Argentine ants with ants able to discriminate among conspecific non-nestmates. This discrimination is linked to the divergence in cuticular hydrocarbon profiles of ants originating from the two supercolonies. Conclusions The presence of these two distinct supercolonies is suggestive of at least two independent introductions of this ant within the Western Cape. Moreover, the pattern of colonisation observed in this study, with the two colonies interspersed, is in agreement with global patterns of Argentine ant invasions. Our findings are of interest because recent studies show that Argentine ants from South Africa are different from those identified in other introduced ranges and therefore provide an opportunity to further understand factors that determine the distributional and spread patterns of Argentine ant supercolonies. PMID:21288369

  5. Repeatability and degree of territorial aggression differs among urban and rural great tits (Parus major).

    PubMed

    Hardman, Samuel I; Dalesman, Sarah

    2018-03-22

    Animals in urban habitats face many novel selection pressures such as increased human population densities and human disturbance. This is predicted to favour bolder and more aggressive individuals together with greater flexibility in behaviour. Previous work has focussed primarily on studying these traits in captive birds and has shown increased aggression and reduced consistency between traits (behavioural syndromes) in birds from urban populations. However, personality (consistency within a behavioural trait) has not been well studied in the wild. Here we tested whether urban free-living male great tits show greater territorial aggression than rural counterparts. We also tested predictions that both behavioural syndromes and personality would show lower consistency in urban populations. We found that urban populations were more aggressive than rural populations and urban birds appeared to show lower levels of individual behavioural repeatability (personality) as predicted. However, we found no effect of urbanisation on behavioural syndromes (correlations between multiple behavioural traits). Our results indicate that urban environments may favour individuals which exhibit increased territorial aggression and greater within-trait flexibility which may be essential to success in holding urban territories. Determining how urban environments impact key fitness traits will be important in predicting how animals cope with ongoing urbanisation.

  6. Coupling Aggressive Mass Removal with Microbial Reductive Dechlorination for Remediation of DNAPL Source Zones: A Review and Assessment

    PubMed Central

    Christ, John A.; Ramsburg, C. Andrew; Abriola, Linda M.; Pennell, Kurt D.; Löffler, Frank E.

    2005-01-01

    The infiltration of dense non-aqueous-phase liquids (DNAPLs) into the saturated subsurface typically produces a highly contaminated zone that serves as a long-term source of dissolved-phase groundwater contamination. Applications of aggressive physical–chemical technologies to such source zones may remove > 90% of the contaminant mass under favorable conditions. The remaining contaminant mass, however, can create a rebounding of aqueous-phase concentrations within the treated zone. Stimulation of microbial reductive dechlorination within the source zone after aggressive mass removal has recently been proposed as a promising staged-treatment remediation technology for transforming the remaining contaminant mass. This article reviews available laboratory and field evidence that supports the development of a treatment strategy that combines aggressive source-zone removal technologies with subsequent promotion of sustained microbial reductive dechlorination. Physical–chemical source-zone treatment technologies compatible with posttreatment stimulation of microbial activity are identified, and studies examining the requirements and controls (i.e., limits) of reductive dechlorination of chlorinated ethenes are investigated. Illustrative calculations are presented to explore the potential effects of source-zone management alternatives. Results suggest that, for the favorable conditions assumed in these calculations (i.e., statistical homogeneity of aquifer properties, known source-zone DNAPL distribution, and successful bioenhancement in the source zone), source longevity may be reduced by as much as an order of magnitude when physical–chemical source-zone treatment is coupled with reductive dechlorination. PMID:15811838

  7. Aggressive behavior and employment histories in patients from an internal medicine outpatient clinic.

    PubMed

    Sansone, Randy A; Leung, Justin S; Wiederman, Michael W

    2013-01-01

    A number of studies have examined the relationships between aggression and various facets of the work environment. However, to our knowledge, the relationship between self-reported aggressive behaviors and corresponding employment histories has never been previously explored. Using a cross-sectional approach and a self-report survey methodology in a consecutive sample of 325 internal medicine outpatients, we examined lifetime histories of 21 aggressive behaviors and 4 employment variables. In both men and women, a higher number of aggressive behaviors correlated with a greater number of different jobs held, greater likelihood of being paid "under the table," and a greater number of firings. However, only in men was the number of aggressive behaviors related to the percentage of time employed as an adult. According to findings, a history of aggressive behavior appears to be associated with compromised employment viability in adulthood. Copyright © 2013 Elsevier Inc. All rights reserved.

  8. Chemical camouflage--a frog's strategy to co-exist with aggressive ants.

    PubMed

    Rödel, Mark-Oliver; Brede, Christian; Hirschfeld, Mareike; Schmitt, Thomas; Favreau, Philippe; Stöcklin, Reto; Wunder, Cora; Mebs, Dietrich

    2013-01-01

    Whereas interspecific associations receive considerable attention in evolutionary, behavioural and ecological literature, the proximate bases for these associations are usually unknown. This in particular applies to associations between vertebrates with invertebrates. The West-African savanna frog Phrynomantis microps lives in the underground nest of ponerine ants (Paltothyreus tarsatus). The ants usually react highly aggressively when disturbed by fiercely stinging, but the frog is not attacked and lives unharmed among the ants. Herein we examined the proximate mechanisms for this unusual association. Experiments with termites and mealworms covered with the skin secretion of the frog revealed that specific chemical compounds seem to prevent the ants from stinging. By HPLC-fractionation of an aqueous solution of the frogs' skin secretion, two peptides of 1,029 and 1,143 Da were isolated and found to inhibit the aggressive behaviour of the ants. By de novo sequencing using tandem mass spectrometry, the amino acid sequence of both peptides consisting of a chain of 9 and 11 residues, respectively, was elucidated. Both peptides were synthesized and tested, and exhibited the same inhibitory properties as the original frog secretions. These novel peptides most likely act as an appeasement allomone and may serve as models for taming insect aggression.

  9. REPEATED REDUCTIVE AND OXIDATIVE TREATMENTS ON GRANULAR ACTIVATED CARBON

    EPA Science Inventory

    Fenton oxidation and Fenton oxidation preceded by reduction solutions were applied to granular activated carbon (GAC) to chemically regenerate the adsorbent. No adsorbate was present on the GAC so physicochemical effects from chemically aggressive regeneration of the carbon coul...

  10. Aggression at Age 5 as a Function of Prenatal Exposure to Cocaine, Gender, and Environmental Risk

    PubMed Central

    Bendersky, Margaret; Bennett, David; Lewis, Michael

    2006-01-01

    Objective To examine childhood aggression at age 5 in a multiple risk model that includes cocaine exposure, environmental risk, and gender as predictors. Methods Aggression was assessed in 206 children by using multiple methods including teacher report, parent report, child’s response to hypothetical provocations, and child’s observed behavior. Also examined was a composite score that reflected high aggression across contexts. Results Multiple regression analyses indicated that a significant amount of variance in each of the aggression measures and the composite was explained by the predictors. The variables that were independently related differed depending on the outcome. Cocaine exposure, gender, and environmental risk were all related to the composite aggression score. Conclusions Cocaine exposure, being male, and a high-risk environment were all predictive of aggressive behavior at 5 years. It is this group of exposed boys at high environmental risk that is most likely to show continued aggression over time. PMID:15827351

  11. Looking for reward in all the wrong places: dopamine receptor gene polymorphisms indirectly affect aggression through sensation-seeking.

    PubMed

    Chester, David S; DeWall, C Nathan; Derefinko, Karen J; Estus, Steven; Lynam, Donald R; Peters, Jessica R; Jiang, Yang

    2016-10-01

    Individuals with genotypes that code for reduced dopaminergic brain activity often exhibit a predisposition toward aggression. However, it remains largely unknown how dopaminergic genotypes may increase aggression. Lower-functioning dopamine systems motivate individuals to seek reward from external sources such as illicit drugs and other risky experiences. Based on emerging evidence that aggression is a rewarding experience, we predicted that the effect of lower-functioning dopaminergic functioning on aggression would be mediated by tendencies to seek the environment for rewards. Caucasian female and male undergraduates (N = 277) were genotyped for five polymorphisms of the dopamine D2 receptor (DRD2) gene; they reported their previous history of aggression and their dispositional reward-seeking. Lower-functioning DRD2 profiles were associated with greater sensation-seeking, which then predicted greater aggression. Our findings suggest that lower-functioning dopaminergic activity puts individuals at risk for violence because it motivates them to experience aggression's hedonically rewarding qualities.

  12. Estimation of the Driving Style Based on the Users’ Activity and Environment Influence

    PubMed Central

    Sysoev, Mikhail; Kos, Andrej; Guna, Jože; Pogačnik, Matevž

    2017-01-01

    New models and methods have been designed to predict the influence of the user’s environment and activity information to the driving style in standard automotive environments. For these purposes, an experiment was conducted providing two types of analysis: (i) the evaluation of a self-assessment of the driving style; (ii) the prediction of aggressive driving style based on drivers’ activity and environment parameters. Sixty seven h of driving data from 10 drivers were collected for analysis in this study. The new parameters used in the experiment are the car door opening and closing manner, which were applied to improve the prediction accuracy. An Android application called Sensoric was developed to collect low-level smartphone data about the users’ activity. The driving style was predicted from the user’s environment and activity data collected before driving. The prediction was tested against the actual driving style, calculated from objective driving data. The prediction has shown encouraging results, with precision values ranging from 0.727 up to 0.909 for aggressive driving recognition rate. The obtained results lend support to the hypothesis that user’s environment and activity data could be used for the prediction of the aggressive driving style in advance, before the driving starts. PMID:29065476

  13. Early social environment influences the behaviour of a family-living lizard

    PubMed Central

    2017-01-01

    Early social environment can play a significant role in shaping behavioural development. For instance, in many social mammals and birds, isolation rearing results in individuals that are less exploratory, shyer, less social and more aggressive than individuals raised in groups. Moreover, dynamic aspects of social environments, such as the nature of relationships between individuals, can also impact the trajectory of development. We tested if being raised alone or socially affects behavioural development in the family-living tree skink, Egernia striolata. Juveniles were raised in two treatments: alone or in a pair. We assayed exploration, boldness, sociability and aggression repeatedly throughout each juvenile's first year of life, and also assessed social interactions between pairs to determine if juveniles formed dominant–subordinate relationships. We found that male and/or the larger skinks within social pairs were dominant. Developing within this social environment reduced skink growth, and subordinate skinks were more prone to tail loss. Thus, living with a conspecific was costly for E. striolata. The predicted negative effects of isolation failed to materialize. Nevertheless, there were significant differences in behavioural traits depending on the social environment (isolated, dominant or subordinate member of a pair). Isolated skinks were more social than subordinate skinks. Subordinate skinks also became more aggressive over time, whereas isolated and dominant skinks showed invariable aggression. Dominant skinks became bolder over time, whereas isolated and subordinate skinks were relatively stable in their boldness. In summary, our study is evidence that isolation rearing does not consistently affect behaviour across all social taxa. Our study also demonstrates that the social environment plays an important role in behavioural development of a family-living lizard. PMID:28573001

  14. Family environment interacts with CRHR1 rs17689918 to predict mental health and behavioral outcomes.

    PubMed

    Roy, Arunima; Laas, Kariina; Kurrikoff, Triin; Reif, Andreas; Veidebaum, Toomas; Lesch, Klaus-Peter; Harro, Jaanus

    2018-05-14

    Corticotrophin-releasing hormone receptor-1 gene (CRHR1) variants have been implicated in mental health. However, little is known of the effects of CRHR1 on long-term mental health and behavior in presence of environmental stressors. We assess the effects of CRHR1 variant (rs17689918)-by-environment interactions on emotionality and behavioral traits, including anxiety, depression, aggression and antisocial behaviors. We also determine effects of rs17689918-by-environment-by-sex interactions on the above-mentioned outcomes. Genotypic assessments were carried out in 564 children (mean age 10 years, 52.5% females) from the ongoing longitudinal Estonian Children Personality Behaviour and Health Study (ECPBHS). Information on stressful life events and family relationships were available at baseline and information on behavioral and mental health outcomes (self- and parent-reports) were available at follow-up ages of 18 and 25 years. ANOVAs were used to determine associations of two-way CRHR1-by-environment and three-way CRHR1-by-sex-by-environment interactions on behavioral and mental health outcomes. Two-way CRHR1 interaction effects showed associations between low familial warmth and hostility in individuals with the GG genotype. Associations of low familial warmth with aggression, of higher number of stressful life events with aggression, and of stressful live events with anxious-depressive symptoms were noted in male A-allele carriers and female GG homozygotes. CRHR1-by-familial environment interactions influence both outwardly-directed aggression as well as mood and anxiety disorder symptoms in a sex-specific manner. The type of environmental stressor can also influence effects of CRHR1 on behavioral and mental health outcomes. Copyright © 2018 Elsevier Inc. All rights reserved.

  15. doublesex alters aggressiveness as a function of social context and sex in the polyphenic beetle Onthophagus taurus.

    PubMed

    Beckers, Oliver M; Kijimoto, Teiya; Moczek, Armin P

    2017-10-01

    Despite sharing nearly the same genome, individuals within the same species can vary drastically in both morphology and behaviour as a function of developmental stage, sex or developmental plasticity. Thus, regulatory processes must exist that enable the stage-, sex- or environment-specific expression of traits and their integration during ontogeny, yet exactly how trait complexes are co-regulated and integrated is poorly understood. In this study, we explore the developmental genetic basis of the regulation and integration of environment-dependent sexual dimorphism in behaviour and morphology in the horn-polyphenic dung beetle Onthophagus taurus through the experimental manipulation of the transcription factor doublesex (dsx). The gene dsx plays a profound role in the developmental regulation of morphological differences between sexes as well as alternative male morphs by inhibiting horn formation in females but enabling nutrition-responsive horn growth in males. Specifically, we investigated whether experimental downregulation of dsx expression affects male and female aggressive and courtship behaviours in two social contexts: interactions between individuals of the same sex and interactions between males and females. We find that dsx downregulation significantly alters aggressiveness in both males and females, yet does so differently for both sexes as a function of social context: dsx RNAi males exhibited elevated aggression towards males but showed reduced aggression towards females, whereas dsx RNAi females became more aggressive towards males, while their aggressiveness towards other females was unaffected. Moreover, we document unexpectedly high levels of female aggression independent of dsx treatment in both wild-type and control-injected individuals. Lastly, we found no effects of dsx RNAi on courtship and mating behaviours. We discuss the role of dsx in the regulation of sex-specific and plastic behaviours, the unexpectedly high levels of aggression of hornless dsx RNAi males in relation to the well-established description of the hornless sneaker phenotype and the potential ecological function of high female aggression.

  16. Neural mediators of the intergenerational transmission of family aggression

    PubMed Central

    Saxbe, Darby; Del Piero, Larissa Borofsky; Immordino-Yang, Mary Helen; Kaplan, Jonas Todd; Margolin, Gayla

    2015-01-01

    Youth exposed to family aggression may become more aggressive themselves, but the mechanisms of intergenerational transmission are understudied. In a longitudinal study, we found that adolescents’ reduced neural activation when rating their parents’ emotions, assessed via magnetic resonance imaging, mediated the association between parents’ past aggression and adolescents’ subsequent aggressive behavior toward parents. A subsample of 21 youth, drawn from the larger study, underwent magnetic resonance imaging scanning proximate to the second of two assessments of the family environment. At Time 1 (when youth were on average 15.51 years old) we measured parents’ aggressive marital and parent–child conflict behaviors, and at Time 2 (≈2 years later), we measured youth aggression directed toward parents. Youth from more aggressive families showed relatively less activation to parent stimuli in brain areas associated with salience and socioemotional processing, including the insula and limbic structures. Activation patterns in these same areas were also associated with youths’ subsequent parent-directed aggression. The association between parents’ aggression and youths’ subsequent parent-directed aggression was statistically mediated by signal change coefficients in the insula, right amygdala, thalamus, and putamen. These signal change coefficients were also positively associated with scores on a mentalizing measure. Hypoarousal of the emotional brain to family stimuli may support the intergenerational transmission of family aggression. PMID:26073067

  17. Physical aggressive resident behavior during hygienic care.

    PubMed

    Farrell Miller, M

    1997-05-01

    Management of aggressive behavior has been identified as a concern for nursing staff who provide institutional care for cognitively impaired elderly. The Omnibus Reconciliation Act (OBRA '87) mandates a trial reduction in the use of chemical and physical restraints, and the development of nursing interventions for the management of behavioral disorders of institutionalized cognitively impaired elderly. Most skilled nursing facilities, however, are limited in their ability to provide environmental and behavioral programs to manage aggressive patient behavior. For the purposes of this study, physically aggressive behavior was identified as threatened or actual aggressive patient contact which has taken place between a patient and a member of the nursing staff. This study explored the nursing staff's responses to patient physical aggression and the effects that physical aggression had on them and on nursing practice from the perspective of the nursing staff. Nursing staff employed on one Dementia Special Care Unit (DSCU) were invited to participate. Interviews with nursing staff were analyzed using qualitative descriptive methods described by Miles and Huberman (1994). Nursing staff reported that they were subjected to aggressive patient behaviors ranging from verbal threats to actual physical violence. Nursing staff reported that showering a resident was the activity of daily living most likely to provoke patient to staff physical aggression. The findings revealed geropsychiatric nursing practices for the management of physically aggressive residents, and offered recommendations for improving the safety of nursing staff and residents on a secured DSCU.

  18. Persulfate Oxidation Regeneration of Granular Activated Carbon: Reversible Impacts on Sorption Behavior

    EPA Science Inventory

    Chemical oxidation regeneration of granular activated carbon (GAC) is a developing technology that can be carried out utilizing thermally-activated persulfate. During chemical regeneration of GAC, aggressive oxidative conditions lead to high acidity (pH < 2) and the accumulation ...

  19. Polyvinylpyrrolidone- (PVP-) coated silver aggregates for high performance surface-enhanced Raman scattering in living cells.

    PubMed

    Tan, Xuebin; Wang, Zhuyuan; Yang, Jing; Song, Chunyuan; Zhang, Ruohu; Cui, Yiping

    2009-11-04

    A biocompatible and stable surface-enhanced Raman scattering (SERS) probe has been successfully synthesized through a simple route with silver aggregates. Polyvinylpyrrolidone (PVP), a biocompatible polymer, was utilized to control the aggregation process and improve the chemical stability of the aggregates. Extinction spectroscopy and TEM results show the aggregation degree and core-shell structure of the probe. It is found that when we employ 4-mercaptobenzoic acid (4MBA), crystal violet (CV), Rhodamine 6G (R6G) or 4,4'-bipyridine molecules as Raman reporters, the SERS signal from the proposed probe can remain at a high level under aggressive chemical environments, even after being incorporated into living cells. In comparison with the traditional probes without the PVP shell, the new ones exhibit strong surface-enhanced effects and low toxicity towards living cells. We demonstrate that the PVP-coated silver aggregates are highly SERS effective, for which the fabrication protocol is advantageous in its simplicity and reproducibility.

  20. MERCURY MEASUREMENTS FOR SOLIDS MADE RAPIDLY, SIMPLY, AND INEXPENSIVELY

    EPA Science Inventory

    While traditional methods for determining mercury in solid samples involve the use of aggressive chemicals to dissolve the matrix and the use of other chemicals to properly reduce the mercury to the volatile elemental form, pyrolysis-based analyzers can be used by directly weighi...

  1. 42 CFR 483.136 - Evaluating whether an individual with mental retardation requires specialized services (PASARR/MR).

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... functional capacity; (10) Social development, such as interpersonal skills, recreation-leisure skills, and...) Learn new skills without aggressive and consistent training; (F) Apply skills learned in a training situation to other environments or settings without aggressive and consistent training; (G) Demonstrate...

  2. Correlates of Restraint and Seclusion for Adults with Intellectual Disabilities in Community Services

    ERIC Educational Resources Information Center

    Merineau-Cote, J.; Morin, D.

    2013-01-01

    Background: Some individuals with intellectual disabilities (IDs) exhibit aggressive behaviour directed towards themselves, others or the environment. Displaying aggressive behaviour is associated with a number of negative consequences such as the exposure to restrictive interventions. This study aims to identify personal and environmental factors…

  3. Managing Canine Aggression in the Home.

    PubMed

    Pike, Amy

    2018-05-01

    Canine aggression occurring in the home can be a dangerous diagnosis with costly consequences to all members of the household. Management is a key modality in the treatment of canine aggression in the home. A thorough history will detail each trigger, target, and context and allow for the veterinary team to put together a comprehensive management plan. Management allows for the avoidance of future aggressive episodes and minimizes the risks associated with living with a patient with these diagnoses. Although risk cannot be mitigated 100%, thorough management can create a safe environment for the implementation of the behavior treatment plan. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. Chemical Discrimination and Aggressiveness via Cuticular Hydrocarbons in a Supercolony-Forming Ant, Formica yessensis

    PubMed Central

    Kidokoro-Kobayashi, Midori; Iwakura, Misako; Fujiwara-Tsujii, Nao; Fujiwara, Shingo; Sakura, Midori; Sakamoto, Hironori; Higashi, Seigo; Hefetz, Abraham; Ozaki, Mamiko

    2012-01-01

    Background Territorial boundaries between conspecific social insect colonies are maintained through nestmate recognition systems. However, in supercolony-forming ants, which have developed an extraordinary social organization style known as unicoloniality, a single supercolony extends across large geographic distance. The underlying mechanism is considered to involve less frequent occurrence of intraspecific aggressive behaviors, while maintaining interspecific competition. Thus, we examined whether the supercolony-forming species, Formica yessensis has a nestmate recognition system similar to that of the multicolonial species, Camponotus japonicus with respect to the cuticular hydrocarbon-sensitive sensillum (CHC sensillum), which responds only to non-nestmate CHCs. We further investigated whether the sensory system reflects on the apparent reduced aggression between non-nestmates typical to unicolonial species. Methodology/Principal Findings F. yessensis constructs supercolonies comprising numerous nests and constitutes the largest supercolonies in Japan. We compared the within-colony or between-colonies’ (1) similarity in CHC profiles, the nestmate recognition cues, (2) levels of the CHC sensillar response, (3) levels of aggression between workers, as correlated with geographic distances between nests, and (4) their genetic relatedness. Workers from nests within the supercolony revealed a greater similarity of CHC profiles compared to workers from colonies outside it. Total response of the active CHC sensilla stimulated with conspecific alien CHCs did not increase as much as in case of C. japonicus, suggesting that discrimination of conspecific workers at the peripheral system is limited. It was particularly limited among workers within a supercolony, but was fully expressed for allospecific workers. Conclusions/Significance We demonstrate that chemical discrimination between nestmates and non-nestmates in F. yessensis was not clear cut, probably because this species has only subtle intraspecific differences in the CHC pattern that typify within a supercolony. Such an incomplete chemical discrimination via the CHC sensilla is thus an important factor contributing to decreased occurrence of intraspecific aggressive behavior especially within a supercolony. PMID:23115632

  5. [Sexual aggression against girls and adult women--causes and consequences].

    PubMed

    Bitzer, J

    2005-04-01

    The causes of sexual aggression are multiple. Bioevolutionary rooted behavioral dispositions (sexual aggressiveness of men as a reproductive strategy) are enforced by specific male dominated structures of society and socially determined stereotypes of female roles which deter women from self determination of their sexuality; these macrosocial factors combine with individual conditions of socialization, in which violence plays an important role. With respect to the consequences of sexual aggression primary victimization (the trauma itself with physical and psychological harm) can be distinguished from secondary victimization (devaluation and mistrust in the social environment). The degree of negative health outcomes depends on risk factors like previous abuse, severity of the violent act, and lack of social support. Prevention must aim at changes of societal conditions that enhance sexual aggression and the establishment of programs for men and women at risk in which techniques of control of sexual aggression, attenuation and inhibition can be learnt.

  6. Aggressive behaviour by people with dementia in residential care settings: a review.

    PubMed

    Pulsford, D; Duxbury, J

    2006-10-01

    This paper considers the phenomenon of aggressive behaviour perpetrated by people with dementia in residential care settings. Aggressive behaviour is defined in the context of people with dementia, and the problem of ascertaining the incidence of aggression among people with dementia is discussed. The emotional impact of assaults on nurses and other professionals is highlighted, and differing perspectives on the causation of aggressive behaviour are considered. Management strategies derived from the physical/pharmacological; environment management; behaviour modification and person-centred approaches are reviewed. Our conclusion is that while certain strategies appear to reflect good and common sense practice, in particular those deriving from the person-centred approach, there is no clear research evidence for the general effectiveness of any one management approach, and each has drawbacks of a practical or ethical nature. There is also little empirical information about how professional carers actually manage aggressive behaviour in practice.

  7. Modulation of Fgfr1a signaling in zebrafish reveals a genetic basis for the aggression-boldness syndrome.

    PubMed

    Norton, William H J; Stumpenhorst, Katharina; Faus-Kessler, Theresa; Folchert, Anja; Rohner, Nicolas; Harris, Matthew P; Callebert, Jacques; Bally-Cuif, Laure

    2011-09-28

    Behavioral syndromes are suites of two or more behaviors that correlate across environmental contexts. The aggression-boldness syndrome links aggression, boldness, and exploratory activity in a novel environment. Although aggression-boldness has been described in many animals, the mechanism linking its behavioral components is not known. Here we show that mutation of the gene encoding fibroblast growth factor receptor 1a (fgfr1a) simultaneously increases aggression, boldness, and exploration in adult zebrafish. We demonstrate that altered Fgf signaling also results in reduced brain histamine levels in mutants. Pharmacological increase of histamine signaling is sufficient to rescue the behavioral phenotype of fgfr1a mutants. Together, we show that a single genetic locus can underlie the aggression-boldness behavioral syndrome. We also identify one of the neurotransmitter pathways that may mediate clustering of these behaviors.

  8. Differential diagnosis and management of human-directed aggression in cats.

    PubMed

    Frank, Diane; Dehasse, Joel

    2003-03-01

    Human-directed aggression in cats should be evaluated as a multifactorial problem. It results from the combined actions of heredity, environment, learning, human social requirements (or needs), client interactions, lack of understanding of normal feline behavior, unrealistic client expectations, and lack of meeting the cat's basic ethologic needs. Managing human-directed aggression in cats encompasses the use of environmental modification, therapies, and, when and if needed, regulatory drugs so as to increase learning capabilities and adaptation and decrease danger to the human victims.

  9. The Unexpected Effects of Beneficial and Adverse Social Experiences during Adolescence on Anxiety and Aggression and Their Modulation by Genotype

    PubMed Central

    Meyer, Neele; Richter, S. Helene; Schreiber, Rebecca S.; Kloke, Vanessa; Kaiser, Sylvia; Lesch, Klaus-Peter; Sachser, Norbert

    2016-01-01

    Anxiety and aggression are part of the behavioral repertoire of humans and animals. However, in their exaggerated form both can become maladaptive and result in psychiatric disorders. On the one hand, genetic predisposition has been shown to play a crucial modulatory role in anxiety and aggression. On the other hand, social experiences have been implicated in the modulation of these traits. However, so far, mainly experiences in early life phases have been considered crucial for shaping anxiety-like and aggressive behavior, while the phase of adolescence has largely been neglected. Therefore, the aim of the present study was to elucidate how levels of anxiety-like and aggressive behavior are shaped by social experiences during adolescence and serotonin transporter (5-HTT) genotype. For this purpose, male mice of a 5-HTT knockout mouse model including all three genotypes (wildtype, heterozygous and homozygous 5-HTT knockout mice) were either exposed to an adverse social situation or a beneficial social environment during adolescence. This was accomplished in a custom-made cage system where mice experiencing the adverse environment were repeatedly introduced to the territory of a dominant opponent but had the possibility to escape to a refuge cage. Mice encountering beneficial social conditions had free access to a female mating partner. Afterwards, anxiety-like and aggressive behavior was assessed in a battery of tests. Surprisingly, unfavorable conditions during adolescence led to a decrease in anxiety-like behavior and an increase in exploratory locomotion. Additionally, aggressive behavior was augmented in animals that experienced social adversity. Concerning genotype, homozygous 5-HTT knockout mice were more anxious and less aggressive than heterozygous 5-HTT knockout and wildtype mice. In summary, adolescence is clearly an important phase in which anxiety-like and aggressive behavior can be shaped. Furthermore, it seems that having to cope with challenge during adolescence instead of experiencing throughout beneficial social conditions leads to reduced levels of anxiety-like behavior. PMID:27303275

  10. TELEPHONIC PRESENTATION: MERCURY MEASUREMENTS FOR SOLIDS MADE RAPIDLY, SIMPLY, AND INEXPENSIVELY

    EPA Science Inventory

    While traditional methods for determining mercury in solid samples involve the use of aggressive chemicals to dissolve the matrix and the use of other chemicals to properly reduce the mercury to the volatile elemental form, pyrolysis-based analyzers can be used by directly weighi...

  11. TRANSPORT PROPERTIES OF CROSSLINKABLE POLYIMIDE BLENDS. (R824727)

    EPA Science Inventory

    Abstract

    The use of polymeric membranes for separation of chemically aggressive media, or at elevated temperatures, has been limited by membrane availability. While a number of polymers are both resistant to chemical dissolution and thermally stable to over 300°C,...

  12. Do Candida spp. "read" Nietzsche? Can xenobiotics modulate their aggressiveness? Proposition that chemicals may interfere in their virulence attributes.

    PubMed

    Rosa, Edvaldo Antonio Ribeiro

    2012-01-01

    As well as the host, opportunist Candida spp. enface all sorts of exogenous chemicals, so-called xenobiotics. It is plausible that xenobiotics exert some effects on such microorganisms; among them, the modulation of virulence attributes.

  13. Links between marital and parent-child interactions: moderating role of husband-to-wife aggression.

    PubMed

    Margolin, Gayla; Gordis, Elana B; Oliver, Pamella H

    2004-01-01

    The present study examined how marital conflict may compromise parenting by identifying interdependencies across marital and parent-child subsystems in a sample of 86 two-parent families with a child aged 9-13. The study used direct observation of three family discussions to examine interdependencies across family subsystems. The study also assessed whether a history of husband-to-wife aggression strengthened interdependencies. Overall, families with husband-to-wife aggression showed a negative tone that pervaded throughout the family. Consistent with theories about physically aggressive men tending to withdraw from conflict, fathers who had engaged in husband-to-wife aggression showed an association between marital hostilities and lower levels of empathy toward their children. Consistent with stress theories, women who had been exposed to husband-to-wife aggression showed a link between marital hostilities and negative affect when interacting with their children. These findings illustrate how a history of exposure to marital aggression can create a family environment of multiple risks for children. For children in families with prior marital aggression, ongoing marital hostilities can be linked to the additional risk of erosions in parental support.

  14. The Association Between Forms of Aggression, Leadership, and Social Status Among Urban Youth

    PubMed Central

    Baker, Courtney N.; Paskewich, Brooke S.; Leff, Stephen S.

    2014-01-01

    While much prior research has documented the negative associations between aggression, peer relationships, and social skills, other research has begun to examine whether forms of aggression also may be associated with prosocial skills and increased social status. However, few studies have examined these associations within diverse samples of elementary aged youth. The current study examined the associations between aggression, popularity, social preference, and leadership among 227 urban, ethnic minority (74 % African American, 9 % bi-racial including African American, 12 % other ethnic minorities, and 5 % European American) elementary school youth (average age 9.5 years, 48.5 % female). Results indicated that in an urban, high risk environment, displaying aggressive behaviors was associated with increased perceived popularity, decreased social preference, and, in some cases, increased perceived leadership. The results also suggested gender differences in the association between the forms of aggression (i.e. relational and overt) and popularity. The current study underscores the importance of examining youth leadership along with forms of aggression and social status among urban minority youth. Implications for future research and aggression prevention programming are highlighted. PMID:23086015

  15. The association between forms of aggression, leadership, and social status among urban youth.

    PubMed

    Waasdorp, Tracy Evian; Baker, Courtney N; Paskewich, Brooke S; Leff, Stephen S

    2013-02-01

    While much prior research has documented the negative associations between aggression, peer relationships, and social skills, other research has begun to examine whether forms of aggression also may be associated with prosocial skills and increased social status. However, few studies have examined these associations within diverse samples of elementary aged youth. The current study examined the associations between aggression, popularity, social preference, and leadership among 227 urban, ethnic minority (74 % African American, 9 % bi-racial including African American, 12 % other ethnic minorities, and 5 % European American) elementary school youth (average age 9.5 years, 48.5 % female). Results indicated that in an urban, high risk environment, displaying aggressive behaviors was associated with increased perceived popularity, decreased social preference, and, in some cases, increased perceived leadership. The results also suggested gender differences in the association between the forms of aggression (i.e. relational and overt) and popularity. The current study underscores the importance of examining youth leadership along with forms of aggression and social status among urban minority youth. Implications for future research and aggression prevention programming are highlighted.

  16. Neural Correlates of Aggressive Behavior in Real Time: a Review of fMRI Studies of Laboratory Reactive Aggression

    PubMed Central

    Keedy, Sarah; Berman, Mitchell E.; Lee, Royce; Coccaro, Emil F.

    2017-01-01

    Purpose of review Aggressive behavior has adaptive value in many natural environments; however, it places substantial burden and costs on human society. For this reason, there has long been interest in understanding the neurobiological basis of aggression. This interest, and the flourishing of neuroimaging research in general, has spurred the development of a large and growing scientific literature on the topic. As a result, a neural circuit model of aggressive behavior has emerged that implicates interconnected brain regions that are involved in emotional reactivity, emotion regulation, and cognitive control. Recent findings Recently, behavioral paradigms that simulate provocative interactions have been adapted to neuroimaging protocols, providing an opportunity to directly probe the involvement of neural circuits in an aggressive interaction. Here we review neuroimaging studies of simulated aggressive interactions in research volunteers. We focus on studies that use a well-validated laboratory paradigm for reactive physical aggression and examine the neural correlates of provocation, retaliation, and evaluating punishment of an opponent. Summary Overall, the studies reviewed support the involvement of neural circuits that support emotional reactivity, emotion regulation, and cognitive control in aggressive behavior. Based on a synthesis of this literature, future research directions are discussed. PMID:29607288

  17. Aggression in children with behavioural/emotional difficulties: seeing aggression on television and video games.

    PubMed

    Mitrofan, Oana; Paul, Moli; Weich, Scott; Spencer, Nicholas

    2014-11-18

    Mental health professionals are often asked to give advice about managing children's aggression. Good quality evidence on contributory environmental factors such as seeing aggression on television and in video games is relatively lacking, although societal and professional concerns are high. This study investigated possible associations between seeing aggression in such media and the aggressive behaviour of children attending specialist outpatient child and adolescent mental health services (CAMHS). In this mixed methods study, forty-seven British children aged 7-11 years with behavioural/emotional difficulties attending CAMHS and their carers participated in a survey; twenty purposively-selected children and a parent/carer of theirs participated in a qualitative study, involving semi-structured interviews, analysed using the Framework Analysis Approach; findings were integrated. Children attending CAMHS exhibit clinically significant aggression, of varying types and frequency. They see aggression in multiple real and virtual settings. Verbal aggression was often seen, frequently exhibited and strongly associated with poor peer relationships and low prosocial behaviour. Children did not think seeing aggression influences their own behaviour but believed it influences others. Carers regarded aggression as resulting from a combination of inner and environmental factors and seeing aggression in real-life as having more impact than television/video games. There is yet no definitive evidence for or against a direct relationship between aggression seen in the media and aggression in children with behavioural/emotional difficulties. Future research should take an ecological perspective, investigating individual, developmental and environmental factors. Carers, professional organisations and policy makers should address aggression seen in all relevant area of children's lives, primarily real-life and secondly virtual environments.

  18. Signaling aggression.

    PubMed

    van Staaden, Moira J; Searcy, William A; Hanlon, Roger T

    2011-01-01

    From psychological and sociological standpoints, aggression is regarded as intentional behavior aimed at inflicting pain and manifested by hostility and attacking behaviors. In contrast, biologists define aggression as behavior associated with attack or escalation toward attack, omitting any stipulation about intentions and goals. Certain animal signals are strongly associated with escalation toward attack and have the same function as physical attack in intimidating opponents and winning contests, and ethologists therefore consider them an integral part of aggressive behavior. Aggressive signals have been molded by evolution to make them ever more effective in mediating interactions between the contestants. Early theoretical analyses of aggressive signaling suggested that signals could never be honest about fighting ability or aggressive intentions because weak individuals would exaggerate such signals whenever they were effective in influencing the behavior of opponents. More recent game theory models, however, demonstrate that given the right costs and constraints, aggressive signals are both reliable about strength and intentions and effective in influencing contest outcomes. Here, we review the role of signaling in lieu of physical violence, considering threat displays from an ethological perspective as an adaptive outcome of evolutionary selection pressures. Fighting prowess is conveyed by performance signals whose production is constrained by physical ability and thus limited to just some individuals, whereas aggressive intent is encoded in strategic signals that all signalers are able to produce. We illustrate recent advances in the study of aggressive signaling with case studies of charismatic taxa that employ a range of sensory modalities, viz. visual and chemical signaling in cephalopod behavior, and indicators of aggressive intent in the territorial calls of songbirds. Copyright © 2011 Elsevier Inc. All rights reserved.

  19. Aggression on haemodialysis units: a mixed method study.

    PubMed

    Jones, Julia; Nijman, Henk; Ross, Jamie; Ashman, Neil; Callaghan, Patrick

    2014-09-01

    Aggression on haemodialysis units is a growing problem internationally that has received little research attention to date. Aggressive behaviour by patients or their relatives can compromise the safety and well-being of staff and other patients sharing a haemodialysis session. The objectives of the study were twofold: First, to identify the prevalance and nature of aggression on haemodialysis units; and second, to investigate factors that contribute to aggressive behaviour on haemodialysis units. A cross-sectional, sequential mixed method research design was adopted, with two research methods utilised. Incidents of aggressive behaviour were recorded over a 12-month period, using a renal version of the Staff Observation Aggression Scale. Six months after the incident data collection had commenced, semi-structured qualitative interviews were conducted with 29 multidisciplinary members of staff. Over 12 months, 74 aggressive incidents were recorded. The majority of incidents involved verbal aggression, and the perpetrators were a minority of patients, relatives and staff. Two patients were responsible for 38% of all incidents; both patients had mental health problems. Distinct temporal patterns to the aggressive behaviour were observed according to the day of the week and time of day. This study demonstrates that aggression is a significant problem on haemodialysis units, with verbal aggression most prevalent. The temporal patterns to aggression observed are related to the uniqueness of the haemodialysis setting, with a distinctly different treatment environment compared with other healthcare settings. © 2014 European Dialysis and Transplant Nurses Association/European Renal Care Association.

  20. Physical and Chemical Castration of Sex Offenders: A Review.

    ERIC Educational Resources Information Center

    Meyer, Walter J., III; Cole, Collier M.

    1997-01-01

    Provides an overview of physical and chemical castration and its use in controlling sex offenders. Discusses castration and sexual aggression, then focuses on the use of therapeutic physical castration in dealing with those who display unacceptable sexual behaviors. Details legal and ethical issues and the efficacy of testosterone-lowering…

  1. PRESENTED 04/05/2006: MERCURY MEASUREMENTS FOR SOLIDS MADE RAPIDLY, SIMPLY, AND INEXPENSIVELY

    EPA Science Inventory

    While traditional methods for determining mercury in solid samples involve the use of aggressive chemicals to dissolve the matrix and the use of other chemicals to properly reduce the mercury to the volatile elemental form, pyrolysis-based analyzers can be used by directly weighi...

  2. PRESENTED MAY 10, 2005, MERCURY MEASUREMENTS FOR SOLIDS MADE RAPIDLY, SIMPLY, AND INEXPENSIVELY

    EPA Science Inventory

    While traditional methods for determining mercury in solid samples involve the use of aggressive chemicals to dissolve the matrix and the use of other chemicals to properly reduce the mercury to the volatile elemental form, pyrolysis-based analyzers can be used by directly weighi...

  3. Self-Efficacies, Anxiety, and Aggression among African American and Latino Adolescents with Disabilities

    ERIC Educational Resources Information Center

    Brubacher, Michael R.; McMahon, Susan D.; Keys, Christopher B.

    2018-01-01

    Self-appraisals can combine with aspects of the school environment in predicting adolescent emotions and behaviors. This study examined how academic self-efficacy and social self-efficacy are related to anxiety and aggression, and how these relations are moderated by school stressors, academic achievement, and school belonging. The participants of…

  4. Understanding School Climate, Aggression, Peer Victimization, and Bully Perpetration: Contemporary Science, Practice, and Policy

    ERIC Educational Resources Information Center

    Espelage, Dorothy L.; Low, Sabina K.; Jimerson, Shane R.

    2014-01-01

    Existing scholarship suggests that classroom practices, teacher attitudes, and the broader school environment play a critical role in understanding the rates of student reports of aggression, bullying, and victimization as well as correlated behaviors. A more accurate understanding of the nature, origins, maintenance, and prevalence of bullying…

  5. The Effectiveness of Peer Mediation on Student to Student Conflict

    ERIC Educational Resources Information Center

    Mayorga, Mary G.

    2010-01-01

    Conflict in school settings continues to be an area of concern for school administrators, teachers, and parents. Conflict between and among students in their school environment is followed by aggressive behavior that contributes to violent actions. The aggressive behavior may range from verbal attacks to physical attacks that may end up with the…

  6. Does Dampened Physiological Reactivity Protect Youth in Aggressive Family Environments?

    ERIC Educational Resources Information Center

    Saxbe, Darby E.; Margolin, Gayla; Shapiro, Lauren A. Spies; Baucom, Brian R.

    2012-01-01

    Is an attenuated physiological response to family conflict, seen in some youth exposed to early adversity, protective or problematic? A longitudinal study including 54 youth (average age 15.2 years) found that those with higher cumulative family aggression exposure showed lower cortisol output during a laboratory-based conflict discussion with…

  7. Relational Aggression at School: Associations with School Safety and Social Climate

    ERIC Educational Resources Information Center

    Goldstein, Sara E.; Young, Amy; Boyd, Carol

    2008-01-01

    The present study examines how exposure to relational aggression at school is associated with adolescents' perceptions of, and participation in, a hostile school environment. Participants were 1,335 African American and European American adolescents in grades 7 through 12 (52% female, 49% African American). Results indicate that exposure to…

  8. Aggression between siblings: Associations with the home environment and peer bullying.

    PubMed

    Tippett, Neil; Wolke, Dieter

    2015-01-01

    Sibling aggression is a common form of intra-familial aggression, yet has been largely neglected by research. Using an inclusive measure of sibling aggression, this study investigated, firstly, prevalence of sibling aggression and associations with family and household characteristics, and secondly, the relationship between sibling aggression and peer bullying. Participants were 4,237 adolescents from Wave 1 of Understanding Society. Four types of sibling aggression were measured: physical, verbal, stealing and teasing, and combined into composite measures of victimization and perpetration. Regression analysis identified associations with demographic characteristics, family and sibling composition, parent-child relationships and socioeconomic status and explored the link between sibling aggression and involvement in peer bullying. Using a broad definition, sibling aggression was found to be widespread, with 46% of all participants being victimized and 36% perpetrating aggression. Household and family characteristics, including a large family size, male siblings, and financial difficulties were associated with greater rates of sibling aggression. Parenting behavior showed the strongest relationship: harsh parenting increased the risk of sibling aggression while positive parenting protected against it. Sibling aggression was also homotypically related to involvement in peer bullying. Victimization by siblings significantly increased the odds of being a victim of peer bullying, and perpetrators of sibling aggression were more likely to be both peer bullies and bully-victims. Considering the adverse effects of sibling aggression on physical and mental health, the study provides pointers for efforts to reduce the risk of sibling aggression. Furthermore, the link with peer bullying suggests that school anti-bullying efforts should also take account of children's sibling relationships. Aggr. Behav. 41:14-24, 2015. © 2014 Wiley Periodicals, Inc. © 2014 Wiley Periodicals, Inc.

  9. Animal Violence Demystified

    PubMed Central

    Natarajan, Deepa; Caramaschi, Doretta

    2009-01-01

    Violence has been observed in humans and animals alike, indicating its evolutionary/biological significance. However, violence in animals has often been confounded with functional forms of aggressive behavior. Currently, violence in animals is identified primarily as either a quantitative behavior (an escalated, pathological and abnormal form of aggression characterized primarily by short attack latencies, and prolonged and frequent harm-oriented conflict behaviors) or a qualitative one (characterized by attack bites aimed at vulnerable parts of the opponent's body and context independent attacks regardless of the environment or the sex and type of the opponent). Identification of an operational definition for violence thus not only helps in understanding its potential differences from adaptive forms of aggression but also in the selection of appropriate animal models for both. We address this issue theoretically by drawing parallels from research on aggression and appeasement in humans and other animals. We also provide empirical evidences for violence in mice selected for high aggression by comparing our findings with other currently available potentially violent rodent models. The following violence-specific features namely (1) Display of low levels of pre-escalatory/ritualistic behaviors. (2) Immediate and escalated offense durations with low withdrawal rates despite the opponent's submissive supine and crouching/defeat postures. (3) Context independent indiscriminate attacks aimed at familiar/unfamiliar females, anaesthetized males and opponents and in neutral environments. (4) Orientation of attack-bites toward vulnerable body parts of the opponent resulting in severe wounding. (5) Low prefrontal serotonin (5-HT) levels upon repeated aggression. (6) Low basal heart rates and hyporesponsive hypothalamus–pituitary–adrenocortical (HPA) axis were identified uniquely in the short attack latency (SAL) mice suggesting a qualitative difference between violence and adaptive aggression in animals. PMID:20407576

  10. Animal violence demystified.

    PubMed

    Natarajan, Deepa; Caramaschi, Doretta

    2010-01-01

    Violence has been observed in humans and animals alike, indicating its evolutionary/biological significance. However, violence in animals has often been confounded with functional forms of aggressive behavior. Currently, violence in animals is identified primarily as either a quantitative behavior (an escalated, pathological and abnormal form of aggression characterized primarily by short attack latencies, and prolonged and frequent harm-oriented conflict behaviors) or a qualitative one (characterized by attack bites aimed at vulnerable parts of the opponent's body and context independent attacks regardless of the environment or the sex and type of the opponent). Identification of an operational definition for violence thus not only helps in understanding its potential differences from adaptive forms of aggression but also in the selection of appropriate animal models for both. We address this issue theoretically by drawing parallels from research on aggression and appeasement in humans and other animals. We also provide empirical evidences for violence in mice selected for high aggression by comparing our findings with other currently available potentially violent rodent models. The following violence-specific features namely (1) Display of low levels of pre-escalatory/ritualistic behaviors. (2) Immediate and escalated offense durations with low withdrawal rates despite the opponent's submissive supine and crouching/defeat postures. (3) Context independent indiscriminate attacks aimed at familiar/unfamiliar females, anaesthetized males and opponents and in neutral environments. (4) Orientation of attack-bites toward vulnerable body parts of the opponent resulting in severe wounding. (5) Low prefrontal serotonin (5-HT) levels upon repeated aggression. (6) Low basal heart rates and hyporesponsive hypothalamus-pituitary-adrenocortical (HPA) axis were identified uniquely in the short attack latency (SAL) mice suggesting a qualitative difference between violence and adaptive aggression in animals.

  11. Short-term prediction of threatening and violent behaviour in an Acute Psychiatric Intensive Care Unit based on patient and environment characteristics.

    PubMed

    Vaaler, Arne E; Iversen, Valentina C; Morken, Gunnar; Fløvig, John C; Palmstierna, Tom; Linaker, Olav M

    2011-03-18

    The aims of the present study were to investigate clinically relevant patient and environment-related predictive factors for threats and violent incidents the first three days in a PICU population based on evaluations done at admittance. In 2000 and 2001 all 118 consecutive patients were assessed at admittance to a Psychiatric Intensive Care Unit (PICU). Patient-related conditions as actuarial data from present admission, global clinical evaluations by physician at admittance and clinical nurses first day, a single rating with an observer rated scale scoring behaviours that predict short-term violence in psychiatric inpatients (The Brøset Violence Checklist (BVC)) at admittance, and environment-related conditions as use of segregation or not were related to the outcome measure Staff Observation Aggression Scale-Revised (SOAS-R). A multiple logistic regression analysis with SOAS-R as outcome variable was performed. The global clinical evaluations and the BVC were effective and more suitable than actuarial data in predicting short-term aggression. The use of segregation reduced the number of SOAS-R incidents. In a naturalistic group of patients in a PICU segregation of patients lowers the number of aggressive and threatening incidents. Prediction should be based on clinical global judgment, and instruments designed to predict short-term aggression in psychiatric inpatients. NCT00184119/NCT00184132.

  12. Short-term prediction of threatening and violent behaviour in an Acute Psychiatric Intensive Care Unit based on patient and environment characteristics

    PubMed Central

    2011-01-01

    Background The aims of the present study were to investigate clinically relevant patient and environment-related predictive factors for threats and violent incidents the first three days in a PICU population based on evaluations done at admittance. Methods In 2000 and 2001 all 118 consecutive patients were assessed at admittance to a Psychiatric Intensive Care Unit (PICU). Patient-related conditions as actuarial data from present admission, global clinical evaluations by physician at admittance and clinical nurses first day, a single rating with an observer rated scale scoring behaviours that predict short-term violence in psychiatric inpatients (The Brøset Violence Checklist (BVC)) at admittance, and environment-related conditions as use of segregation or not were related to the outcome measure Staff Observation Aggression Scale-Revised (SOAS-R). A multiple logistic regression analysis with SOAS-R as outcome variable was performed. Results The global clinical evaluations and the BVC were effective and more suitable than actuarial data in predicting short-term aggression. The use of segregation reduced the number of SOAS-R incidents. Conclusions In a naturalistic group of patients in a PICU segregation of patients lowers the number of aggressive and threatening incidents. Prediction should be based on clinical global judgment, and instruments designed to predict short-term aggression in psychiatric inpatients. Trial registrations NCT00184119/NCT00184132 PMID:21418581

  13. Multimodal signals: ultraviolet reflectance and chemical cues in stomatopod agonistic encounters

    PubMed Central

    Marshall, N. Justin; Lewis, Sara M.

    2016-01-01

    Complex signals are commonly used during intraspecific contests over resources to assess an opponent's fighting ability and/or aggressive state. Stomatopod crustaceans may use complex signals when competing aggressively for refuges. Before physical attacks, stomatopods assess their opponents using chemical cues and perform threat displays showing a coloured patch, the meral spot. In some species, this spot reflects UV. However, despite their complex visual system with up to 20 photoreceptor classes, we do not know if stomatopods use chromatic or achromatic signals in contests. In a field study, we found that Neogonodactylus oerstedii meral spot luminance varies with sex, habitat and, more weakly, body length. Next, we conducted an experimental manipulation which demonstrated that both chemical cues and chromatic signals are used during contests. In the absence of chemical cues, stomatopods approached an occupied refuge more quickly and performed offensive behaviours at a lower rate. When UV reflectance was absent, stomatopods performed offensive behaviours more frequently and contest duration trended towards shorter fights. These results provide new evidence that UV reflectance and/or visible spectrum luminance is used to amplify threat displays. Our results are the first to demonstrate that chemical and chromatic cues comprise a multimodal signal in stomatopod contests. PMID:27853613

  14. Trajectories of Adolescent Aggression and Family Cohesion: The Potential to Perpetuate or Ameliorate Political Conflict.

    PubMed

    Taylor, Laura K; Merrilees, Christine E; Goeke-Morey, Marcie C; Shirlow, Pete; Cummings, E Mark

    2016-01-01

    Correlations between intergroup violence and youth aggression are often reported. Yet longitudinal research is needed to understand the developmental factors underlying this relation, including between-person differences in within-person change in aggression through the adolescent years. Multilevel modeling was used to explore developmental and contextual influences related to risk for youth aggression using 4 waves of a prospective, longitudinal study of adolescent/mother dyad reports (N = 820; 51% female; 10-20 years old) in Belfast, Northern Ireland, a setting of protracted political conflict. Experience with sectarian (i.e., intergroup) antisocial behavior predicted greater youth aggression; however, that effect declined with age, and youth were buffered by a cohesive family environment. The trajectory of aggression (i.e., intercepts and linear slopes) related to more youth engagement in sectarian antisocial behavior; however, being female and having a more cohesive family were associated with lower levels of youth participation in sectarian acts. The findings are discussed in terms of protective and risk factors for adolescent aggression, and more specifically, participation in sectarian antisocial behavior. The article concludes with clinical and intervention implications, which may decrease youth aggression and the perpetuation of intergroup violence in contexts of ongoing conflict.

  15. Feeding response of sport fish after electrical immobilization, chemical sedation, or both

    USGS Publications Warehouse

    Meinertz, Jeffery R.; Fredricks, Kim T.; Ambrose, Ryan D.; Jackan, Leanna M.; Wise, Jeremy K.

    2012-01-01

    Fishery managers frequently capture wild fish for a variety of fishery management activities. Though some activities can be accomplished without immobilizing the fish, others are accomplished more readily, humanely, and safely (for both the handler and the fish) when fish are immobilized by physical (e.g., electrical immobilization) or chemical sedation. A concern regarding the use of chemical sedatives is that chemical residues may remain in the fillet tissue after the fish recovers from sedation. If those residues are harmful to humans, there is some risk that a postsedated fish released to public waters may be caught and consumed by an angler. To characterize this risk, a series of four trials were conducted. Three trials assessed feeding activity after hatchery-reared fish were electrically immobilized, chemically sedated, or both, and one trial assessed the likelihood of an angler catching a wild fish that had been electrically immobilized and chemically sedated. Results from the first trial indicated that the feeding activity of laboratory habituated fish was variable among and within species after electrical immobilization, chemical sedation, or both. Results from the second trial indicated that the resumption of feeding activity was rapid after being mildly sedated for 45 min. Results from the third trial indicated that the feeding activity of outdoor, hatchery-reared fish was relatively aggressive after fish had been chemically sedated. Results from the fourth trial indicated that the probability of capturing wild fish in a more natural environment by angling after fish had been electrically immobilized and chemically sedated is not likely, i.e., in a group of five fish caught, 3 out of 100 times one would be a fish that had been sedated.

  16. Aggressive Behavior between Siblings and the Development of Externalizing Problems: Evidence from a Genetically Sensitive Study

    ERIC Educational Resources Information Center

    Natsuaki, Misaki N.; Ge, Xiaojia; Reiss, David; Neiderhiser, Jenae M.

    2009-01-01

    This study investigated the prospective links between sibling aggression and the development of externalizing problems using a multilevel modeling approach with a genetically sensitive design. The sample consisted of 780 adolescents (390 sibling pairs) who participated in 2 waves of the Nonshared Environment in Adolescent Development project.…

  17. Assessing and Treating Aggression and Conduct Problems in Schools: Implications from the Coping Power Program

    ERIC Educational Resources Information Center

    Powell, Nicole P.; Boxmeyer, Caroline L.; Baden, Rachel; Stromeyer, Sara; Minney, Jessica A.; Mushtaq, Asia; Lochman, John E.

    2011-01-01

    Children with high levels of aggressive behavior and conduct problems create major management problems in school settings and interfere with the learning environment of their classmates and with their own academic achievement. A contextual social-cognitive model can provide a framework for understanding risk factors involved in the development and…

  18. The Developing Brain: A Largely Overlooked Health Endpoint in Risk Assessments for Synthetic Chemical Substances

    ERIC Educational Resources Information Center

    McElgunn, Barbara

    2010-01-01

    A large body of experimental animal research on the neurotoxic effects of certain environmental chemicals provides evidence of a cascade of neurobehavioural effects including learning deficits, hyperactivity, anxiety, depression, lack of motivation, increased aggressiveness, altered maternal care and bonding, and an over-reaction to small…

  19. Durability of traditional plasters with respect to blast furnace slag-based plaster

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

    Cerulli, T.; Pistolesi, C.; Maltese, C.

    2003-09-01

    Blast furnace slag is a residue of steel production. It is a latent hydraulic binder and is normally used to improve the durability of concrete and mortars. Slag could be also used as rendering mortar for masonry and old buildings. Today, cement and hydraulic lime are the most popular hydraulic binders used to make plasters. They are characterised by a low durability when exposed to the action of chemical and physical agents. The aim of this study was to provide a comparison between the physical-mechanical properties of some renders made with ordinary Portland cement, hydraulic lime, or slag. Furthermore, anmore » investigation was carried out to analyse mortar resistance to several aggressive conditions like acid attack, freezing and thawing cycles, abrasion, sulphate aggression, cycles in ultraviolet screening device, and salt diffusion. The specimens, after chemical attack, have been characterised from the chemical-physical [specific surface according to the BET (Brunauer-Emmet-Teller) method], crystal-chemical (X-ray diffraction, XRD), and morphological (scanning electron microscopy, SEM) points of view.« less

  20. Female contact modulates male aggression via a sexually dimorphic GABAergic circuit in Drosophila

    PubMed Central

    Yuan, Quan; Song, Yuanquan; Yang, Chung-Hui; Jan, Lily Yeh; Jan, Yuh Nung

    2014-01-01

    Intraspecific male-male aggression, important for sexual selection, is regulated by environment, experience and internal states through largely undefined molecular and cellular mechanisms. To understand the basic neural pathway underlying the modulation of this innate behavior, we established a behavioral paradigm in Drosophila melanogaster and investigated the relationship between sexual experience and aggression. In the presence of mating partners, adult male flies exhibited elevated levels of aggression, which was largely suppressed by prior exposure to females via a sexually dimorphic neural mechanism. The suppression involved the ability of male flies to detect females by contact chemosensation through the pheromone-sensing ion channel, ppk29, and was mediated by male specific GABAergic neurons acting upon GABA-a receptor RDL in target cells. Silencing or activation of this circuit led to dis-inhibition or elimination of sex-related aggression, respectively. We propose that the GABAergic inhibition represents a critical cellular mechanism that enables prior experience to modulate aggression. PMID:24241395

  1. Moderating effects of autism on parent views of genetic screening for aggression.

    PubMed

    May, Michael E; Brandt, Rachel C; Bohannan, Joseph K

    2012-10-01

    Advances in gene-environment interaction research have revealed genes that are associated with aggression. However, little is known about parent perceptions of genetic screening for behavioral symptoms like aggression as opposed to diagnosing disabilities. These perceptions may influence future research endeavors involving genetic linkage studies to behavior, including proactive approaches for parents to avoid events leading to aggression. The purpose of this study was to solicit the perspectives of parents who have children with autism about screening for genes associated with aggression, compared to responses from those who have children without disabilities and those planning to have children. Parents of children with autism were more likely to support screening and the use of the results to seek treatment if necessary. Results are discussed in the context of surveillance screening and systematic early intervention for behavioral symptoms related to autism. The results may provide insight for clincians, researchers, policymakers, and advocacy groups related to diagnosing and treating aggression in people with autism.

  2. Can simple tank changes benefit the welfare of laboratory zebrafish Danio rerio?

    PubMed

    Lee, C J; Tyler, C R; Paull, G C

    2018-03-01

    This study examined the effects of simple changes in the tank environment on the wellbeing of laboratory-maintained zebrafish Danio rerio. Groups of D. rerio were either housed in stable environments (where they were maintained in the same tanks throughout the study) or in environments subject to change (where they were periodically moved to novel but identical tanks) and the effects of these treatments on morphometry, reproductive success and aggressive behaviour assessed. No effect of simple tank changes was found on body condition, reproductive output or aggression, for the periods of time studied, indicating that more complex scenarios in housing tank conditions are required for significant welfare benefits for captive D. rerio. © 2018 The Fisheries Society of the British Isles.

  3. Computer modeling the fatigue crack growth rate behavior of metals in corrosive environments

    NASA Technical Reports Server (NTRS)

    Richey, Edward, III; Wilson, Allen W.; Pope, Jonathan M.; Gangloff, Richard P.

    1994-01-01

    The objective of this task was to develop a method to digitize FCP (fatigue crack propagation) kinetics data, generally presented in terms of extensive da/dN-Delta K pairs, to produce a file for subsequent linear superposition or curve-fitting analysis. The method that was developed is specific to the Numonics 2400 Digitablet and is comparable to commercially available software products as Digimatic(sup TM 4). Experiments demonstrated that the errors introduced by the photocopying of literature data, and digitization, are small compared to those inherent in laboratory methods to characterize FCP in benign and aggressive environments. The digitizing procedure was employed to obtain fifteen crack growth rate data sets for several aerospace alloys in aggressive environments.

  4. Aggressive behaviour in adolescent psychiatric settings: what are risk factors, possible interventions and implications for nursing practice? A literature review.

    PubMed

    Hage, S; Van Meijel, B; Fluttert, F; Berden, G F M G

    2009-09-01

    This study was aimed to identify the risk factors of aggressive behaviour in adolescents (1318 years), and to describe available intervention strategies. The findings are evaluated on the basis of their implications for nursing practice. Aggressive behaviour in adolescent psychiatric settings is a neglected research area. The consequences of aggressive behaviour on nurses, other patients and the therapeutic environment can be profound. For the development and implementation of innovative intervention strategies aimed at preventing aggressive behaviour in adolescent psychiatric patients, knowledge of risk factors and evidence-based interventions for aggressive behaviour are of the utmost importance. A systematic search of PubMed, Cinahl, PsychINFO and Cochrane Systematic Reviews (19912007) was employed. The risk factors for aggressive behaviour comprise personal and environmental risk factors. Some risk factors can be influenced by nursing intervention strategies. Available intervention programmes range from interpersonal skills training to massage therapy, parent management training, functional family therapy and multi-systemic therapy. The most effective programmes combine interpersonal skills training with parent management training. No specific nursing intervention programmes were found for dealing with aggressive behaviour in adolescent patients. Nursing staff can assist in achieving a systematic improvement in the treatment outcomes of existing intervention programmes for the prevention of aggression. There is a need for specific nursing intervention programmes to deal with aggressive behaviour in adolescent psychiatric settings.

  5. Estrogenic encounters: How interactions between aromatase and the environment modulate aggression

    PubMed Central

    Trainor, Brian C.; Kyomen, Helen H.; Marler, Catherine A.

    2007-01-01

    Initial investigations into the mechanistic basis of aggression focused on the role of testosterone (T) and a variety of studies on non-human animals found that elevated T levels promote aggression. However, many correlational studies have not detected a significant association between aggression and peripheral T levels. One reason for this inconsistency may be due to differential metabolism of T within the brain, in particular, the conversion of T to estrogen by aromatase. Thus, differences in aromatase enzyme activity, estrogen receptor expression, and related cofactors may have important effects on how steroids affect aggressive behavior. Hormone manipulation studies conducted in a wide variety of species indicate that estrogens modulate aggression. There is also growing evidence that social experience has important effects on the production of estrogen within the brain, and some cases can not be explained by androgenic regulation of aromatase. Such changes in central aromatase activity may play an important role in determining how social experiences affect the probability of whether an individual engages in aggressive behavior. Although studies have been conducted in many taxa, there has been relatively little integration between literatures examining aggression in different species. In this review, we compare and contrast studies examining aggression in birds, mammals, and humans. By taking an integrative approach to our review, we consider mechanisms that could explain species differences in how estrogen modulates aggression. PMID:16376420

  6. The effects of MAOA genotype, childhood trauma, and sex on trait and state-dependent aggression

    PubMed Central

    Verhoeven, Floor E A; Booij, Linda; Kruijt, Anne-Wil; Cerit, Hilâl; Antypa, Niki; Does, Willem

    2012-01-01

    Monoamine oxidase A (MAOA) genotypic variation has been associated with variation in aggression, especially in interaction with childhood trauma or other early adverse events. Male carriers of the low-expressing variant (MAOA-L) with childhood trauma or other early adverse events seem to be more aggressive, whereas female carriers with the high-expressing variant (MAOA-H) with childhood trauma or other early adverse events may be more aggressive. We further investigated the effects of MAOA genotype and its interaction with sex and childhood trauma or other early adverse events on aggression in a young adult sample. We hypothesized that the association between genotype, childhood trauma, and aggression would be different for men and women. We also explored whether this association is different for dispositional (trait) aggression versus aggression in the context of dysphoric mood. In all, 432 Western European students (332 women, 100 men; mean age 20.2) were genotyped for the MAOA gene. They completed measures of childhood trauma, state and trait measures of aggression-related behaviors (STAXI), and cognitive reactivity to sad mood (LEIDS-R), including aggression reactivity. Women with the MAOA-H had higher aggression reactivity scores than women with the MAOA-L. This effect was not observed in men, although the nonsignificant findings in men may be a result of low power. Effects on the STAXI were not observed, nor were there gene by environment interactions on any of the aggression measures. A protective effect of the low-expression variant in women on aggression reactivity is consistent with previous observations in adolescent girls. In females, the MAOA-H may predispose to aggression-related problems during sad mood. PMID:23170243

  7. The effects of MAOA genotype, childhood trauma, and sex on trait and state-dependent aggression.

    PubMed

    Verhoeven, Floor E A; Booij, Linda; Kruijt, Anne-Wil; Cerit, Hilâl; Antypa, Niki; Does, Willem

    2012-11-01

    Monoamine oxidase A (MAOA) genotypic variation has been associated with variation in aggression, especially in interaction with childhood trauma or other early adverse events. Male carriers of the low-expressing variant (MAOA-L) with childhood trauma or other early adverse events seem to be more aggressive, whereas female carriers with the high-expressing variant (MAOA-H) with childhood trauma or other early adverse events may be more aggressive. We further investigated the effects of MAOA genotype and its interaction with sex and childhood trauma or other early adverse events on aggression in a young adult sample. We hypothesized that the association between genotype, childhood trauma, and aggression would be different for men and women. We also explored whether this association is different for dispositional (trait) aggression versus aggression in the context of dysphoric mood. In all, 432 Western European students (332 women, 100 men; mean age 20.2) were genotyped for the MAOA gene. They completed measures of childhood trauma, state and trait measures of aggression-related behaviors (STAXI), and cognitive reactivity to sad mood (LEIDS-R), including aggression reactivity. Women with the MAOA-H had higher aggression reactivity scores than women with the MAOA-L. This effect was not observed in men, although the nonsignificant findings in men may be a result of low power. Effects on the STAXI were not observed, nor were there gene by environment interactions on any of the aggression measures. A protective effect of the low-expression variant in women on aggression reactivity is consistent with previous observations in adolescent girls. In females, the MAOA-H may predispose to aggression-related problems during sad mood.

  8. Review and perspective: Sapphire optical fiber cladding development for harsh environment sensing

    NASA Astrophysics Data System (ADS)

    Chen, Hui; Buric, Michael; Ohodnicki, Paul R.; Nakano, Jinichiro; Liu, Bo; Chorpening, Benjamin T.

    2018-03-01

    The potential to use single-crystal sapphire optical fiber as an alternative to silica optical fibers for sensing in high-temperature, high-pressure, and chemically aggressive harsh environments has been recognized for several decades. A key technological barrier to the widespread deployment of harsh environment sensors constructed with sapphire optical fibers has been the lack of an optical cladding that is durable under these conditions. However, researchers have not yet succeeded in incorporating a high-temperature cladding process into the typical fabrication process for single-crystal sapphire fibers, which generally involves seed-initiated fiber growth from the molten oxide state. While a number of advances in fabrication of a cladding after fiber-growth have been made over the last four decades, none have successfully transitioned to a commercial manufacturing process. This paper reviews the various strategies and techniques for fabricating an optically clad sapphire fiber which have been proposed and explored in published research. The limitations of current approaches and future prospects for sapphire fiber cladding are discussed, including fabrication methods and materials. The aim is to provide an understanding of the past research into optical cladding of sapphire fibers and to assess possible material systems for future research on this challenging problem for harsh environment sensors.

  9. Learners' perceptions of learners regarded as having a homosexual orientation in an independent secondary school environment.

    PubMed

    Mostert, Hendrik P; Myburgh, Chris; Poggenpoel, Marie

    2012-10-04

    In schools today discrimination based on sexual orientation takes place on a regular basis. This form of discrimination leads to aggression towards learners perceived to be homosexual, as well as towards those with a homosexual orientation. For more than 15 years South Africa has been a democratic country with laws that protect learners who have a homosexual orientation. Nevertheless, aggression and discrimination towards these learners still occur in schools. Aggression often leads to verbal and physical bullying of the victims by perpetrators. The objectives of this research were to explore and describe Grade 11 learners' experiences of aggression towards learners perceived to be homosexual as well as those with a homosexual orientation in an independent secondary school environment. The research design was qualitative, exploratory, descriptive and contextual in nature. The data for this investigation consisted of essays based on a published newspaper photograph, phenomenological group interviews, observations and field notes. Tesch's method of data analysis was used, and an independent coder assisted. Three themes were identified, discussed and supported by a literature control: that learners experience that it is right and acceptable to have a homosexual orientation; that they experience ambivalence towards homosexual orientation of learners; and experienced feelings that it is wrong to have a homosexual orientation. Recommended guidelines are provided to address aggression towards learners perceived to be homosexual and those with a homosexual orientation.

  10. Having to fight.

    PubMed

    Crowther, Simon; Goodson, Christina; McGuire, James; Dickson, Joanne M

    2013-01-01

    Existing research that attempts to understand aggressive behavior often focuses on adults and/or individual traits. The present study used a Grounded Theory approach to develop a theoretical framework of how younger adolescents constructed an understanding of their own aggressive behavior within the social context of their lives. The participants were 11 adolescents (aged 12-16) who had previously been involved in incidents of aggression at a school for children with emotional and behavioral difficulties. The identified theoretical framework outlined that aggressive behavior was fundamental to an identity of toughness that participants sought to portray to others. This identity emerged in a hostile peer environment to prevent victimization and establish friendships. The findings are discussed in relation to their clinical implications, limitations, and possibilities for further research.

  11. Boldness and aggressiveness in early and late hatched three-spined sticklebacks Gasterosteus aculeatus.

    PubMed

    Ruiz-Gomez, M L; Huntingford, F A

    2012-08-01

    Levels of boldness and the degree of aggressiveness were compared in juvenile three-spined sticklebacks Gasterosteus aculeatus that had hatched early and late in the breeding season. The most striking result found in this study was that early hatched individuals were bolder when exploring a novel environment than were late-hatched individuals. No differences in levels of aggression between early and late hatchlings were found, but a relationship between boldness and aggressiveness was present regardless of hatching date. The implications of these findings are discussed in the light of research on individual variation in behaviour and the development of behavioural syndromes. © 2012 The Authors. Journal of Fish Biology © 2012 The Fisheries Society of the British Isles.

  12. Influences of Gender, Religion, Dietary Patterns, and Mixed-sex Education on Aggressiveness in Children: A Sociodemographic Study in Municipal Primary Schools of South Delhi.

    PubMed

    Jain, Khushbu; Sharma, Schweta; Prajna, Samani Chaitanya; Jain, Viney

    2018-01-01

    Increasing antisocial and violent behaviors in adolescents and young adults present serious challenges for public health. Children with persistent high levels of aggressiveness are often associated with developing conduct disorders later in life. Early detection of highly aggressive children and sociodemographic risk-modifying factors are important for developing effective preventive strategies. The present study was undertaken to assess levels of aggressiveness for detecting highly aggressive children in sample populations of primary school children in an urban setting and determine significant biosociocultural risk-modifying factors in this scenario. The study was conducted during August-September, 2015 in 5 primary schools of South Delhi Municipal Corporation. Sociodemographic data on 2080 students were collected. Overall aggressiveness scores (OA-Scores) were estimated using a self-report questionnaire in Hindi. Categorizing students according to their OA-Scores, the data revealed that highly aggressive children constituted 4.3% of the study population. Analysis showed significant influence of (a) gender: boys displayed higher levels of aggressiveness compared to girls; (b) dietary pattern: omnivores showed higher aggressiveness than vegetarians; and (c) school environment: boys in mixed-sex (coeducational) schools displayed lower aggressiveness than from single-sex schools. Statistically significant influences of religion (Hindu/Muslim) and family type (joint/nuclear) on aggressiveness profiles were not noticeable. Vegetarian diets and mixed-sex education act as protective factors in the development of aggressiveness in children, especially among boys. Extending investigations to populations differing in geography and cultural backgrounds are warranted to verify present results.

  13. Guiding Children "Back from the Edge" Preparing an Environment to Support Children at Risk

    ERIC Educational Resources Information Center

    Andrews, Sarah Werner

    2017-01-01

    "The children who demand more attention than others, who are disruptive, unmotivated, oppositional, aggressive, or do not give us the positive feedback we get from others…This is where we dig in and find compassion, and understanding, and the knowledge that no child wants to be disruptive, oppositional, or aggressive. They do this because…

  14. Teacher and staff perceptions of school environment as predictors of student aggression, victimization, and willingness to intervene in bullying situations.

    PubMed

    Espelage, Dorothy L; Polanin, Joshua R; Low, Sabina K

    2014-09-01

    This study examines how teacher and staff perceptions of the school environment correlate with student self-reports of bullying, aggression, victimization, and willingness to intervene in bullying incidents using multi-informant, multilevel modeling. Data were derived from 3,616 6th grade students across 36 middle schools in the Midwest, who completed survey measures of bullying, aggression, victimization, and willingness to intervene in bullying situations. Teachers and staff (n = 1,447) completed a school environment survey. Bivariate associations between school-level and student self-reports indicated that as teacher and staff perceive aggression as a problem in their school, students reported greater bully perpetration, fighting, peer victimization, and less willingness to intervene. Further, as staff and teacher report greater commitment to prevent bullying and viewed positive teacher and student relationships, there was less bullying, fighting, and peer victimization, and greater willingness to intervene. In a model where all school environment scales were entered together, a school commitment to prevent bullying was associated with less bullying, fighting, and peer victimization. Student-reports of bully perpetration and peer victimization were largely explained by staff and teacher commitment to bully prevention, whereas fighting and willingness to intervene were largely explained by student characteristics (e.g., gender). We conclude that efforts to address bullying and victimization should involve support from the school administration. School psychologists should play an active role in the school climate improvement process, by creating a school climate council consisting of students, parents, and teachers; administering school climate measures; identifying specific school improvement targets from these data, and engaging all stakeholders in the ongoing school improvement plan. PsycINFO Database Record (c) 2014 APA, all rights reserved.

  15. Defensive chemicals of tawny crazy ants, Nylanderia fulva and their toxicity to red imported fire ants (Hymenoptera: Formicidae)

    USDA-ARS?s Scientific Manuscript database

    Nylanderia fulva (Mayr) has been reported as being able to displace Solenopsis invicta Buren, one of the most aggressive invasive ants in the world. Like S. invicta, N. fulva use chemical secretions in their defense/offense, which may contribute to their observed superior competition ability. In t...

  16. Trajectories of adolescent aggression and family cohesion: The potential to perpetuate or ameliorate political conflict

    PubMed Central

    Taylor, Laura K.; Merrilees, Christine E.; Goeke-Morey, Marcie C.; Shirlow, Pete; Cummings, E. Mark

    2014-01-01

    Objective Correlations between intergroup violence and youth aggression are often reported. Yet, longitudinal research is needed to understand the developmental factors underlying this relation, including between-person differences in within-person change in aggression through the adolescent years. Method Multilevel modeling was used to explore developmental and contextual influences related to risk for youth aggression using four waves of a prospective, longitudinal study of adolescent/mother dyad reports (N = 820; 51% female; 10 to 20 years old) in Belfast, Northern Ireland, a setting of protracted political conflict. Results Experience with sectarian (i.e., intergroup) antisocial behavior predicted greater youth aggression; however, that effect declined with age and youth were buffered by a cohesive family environment. The trajectory of aggression (i.e., intercepts and linear slopes) related to more youth engagement in sectarian antisocial behavior; however, being female and having a more cohesive family were associated with lower levels of youth participation in sectarian acts. Conclusions The findings are discussed in terms of protective and risk factors for adolescent aggression, and more specifically, participation in sectarian antisocial behavior. The paper concludes with clinical and intervention implications which may decrease youth aggression and the perpetuation of intergroup violence in contexts of on-going conflict. PMID:25310245

  17. The interactive effect of the MAOA-VNTR genotype and childhood abuse on aggressive behaviors in Chinese male adolescents.

    PubMed

    Zhang, Yun; Ming, Qingsen; Wang, Xiang; Yao, Shuqiao

    2016-06-01

    Gene-environment interactions that moderate aggressive behavior have been identified in association with the MAOA (monoamine oxidase A) gene. The present study examined the moderating effect of MAOA-VNTR (variable number of tandem repeats) on aggression behavior relating to child abuse among Chinese adolescents. A sample of 507 healthy Chinese male adolescents completed the Child Trauma Questionnaire-Short Form (CTQ-SF) and Youth Self-report of the Child Behavior Checklist. The participants' buccal cells were sampled and subjected to DNA analysis. The effects of childhood abuse (CTQ-SF scores), MAOA-VNTR [high-activity allele (H) versus low-activity allele (L)], and their interaction in aggressive behaviors were analyzed by linear regression. Child maltreatment was found to be a significant independent factor in the manifestation of aggressive behavior, whereas MAOA activity was not. There was a significant interaction between MAOA-VNTR and childhood maltreatment in the exhibition of aggressive behaviors. In the context of physical or emotional abuse, boys in the MAOA-L group showed a greater tendency toward aggression than those in the MAOA-H group. Aggressive behavior arising from childhood maltreatment is moderated by MAOA-VNTR, which may be differentially sensitive to the subtype of childhood maltreatment experienced, among Chinese adolescents.

  18. Family Risk Factors Associated With Aggressive Behavior in Chinese Preschool Children.

    PubMed

    Jia, Shoumei; Wang, Ling; Shi, Yingjuan; Li, Ping

    The study explored family predictors of aggressive behavior in preschool children in China. Using a stratified cluster sampling method, 1382 preschool children were recruited from ten kindergarten schools in Shanghai, China. Their parents completed the Child Behavior Checklist (CBCL)-aggression subscale, the Parent Behavior Inventory, the Family Environment Scale, and a demographic questionnaire. The mean age of the 1382 children was 4.97years (SD=.88), with 55.1% (762) boys, and 44.9% (620) girls. According to the CBCL, the prevalence of aggressive behavior in preschool children was 12.4%. Multivariate logistic regression analysis showed that family conflicts (OR = 1.231, 95% CI: 1.115-1.360), hostile/coercive parenting (OR = 1.083, 95% CI: 1.051-1.116), inconsistent parenting between grandparents and parents (OR = 1.658, 95% CI: 1.175-2.341), and more time spent watching TV (OR = 1.999, 95% CI: 1.568-2.550) significantly predicted aggressive behavior of children. Children with more family conflicts who experience hostile/coercive parenting were more likely to engage in aggressive behavior. Moreover, inconsistent parenting attitudes between grandparents and parents, and excessive TV exposure also contributed to childhood aggression. Given that the results of this study show a high prevalence of aggressive behavior in preschool children, future research must pay greater attention to this aspect. Family risk factors identified as relevant to children's aggression in this study provide avenues to develop family-focused strategies for curbing aggression in preschool children. Copyright © 2016 Elsevier Inc. All rights reserved.

  19. Effect of Montmorillonite Nanogel Composite Fillers on the Protection Performance of Epoxy Coatings on Steel Pipelines.

    PubMed

    Atta, Ayman M; El-Saeed, Ashraf M; Al-Lohedan, Hamad A; Wahby, Mohamed

    2017-06-02

    Montmorillonite (MMT) clay mineral is widely used as filler for several organic coatings. Its activity is increased by exfoliation via chemical modification to produce nanomaterials. In the present work, the modification of MMT to form nanogel composites is proposed to increase the dispersion of MMT into epoxy matrices used to fill cracks and holes produced by the curing exotherms of epoxy resins. The dispersion of MMT in epoxy improved both the mechanical and anti-corrosion performance of epoxy coatings in aggressive marine environments. In this respect, the MMT surfaces were chemically modified with different types of 2-acrylamido-2-methyl propane sulfonic acid (AMPS) nanogels using a surfactant-free dispersion polymerization technique. The effect of the chemical structure, nanogel content and the interaction with MMT surfaces on the surface morphology, surface charges and dispersion in the epoxy matrix were investigated for use as nano-filler for epoxy coatings. The modified MMT nanogel epoxy composites showed excellent resistance to mechanical damage and salt spray resistance up to 1000 h. The interaction of MMT nanogel composites with the epoxy matrix and good response of AMPS nanogel to sea water improve their ability to act as self-healing materials for epoxy coatings for steel.

  20. “Hotspots” for Aggression in Licensed Drinking Venues

    PubMed Central

    Graham, Kathryn; Bernards, Sharon; Osgood, D. Wayne; Wells, Samantha

    2011-01-01

    Introduction and Aims In order to better understand the social context of barroom aggression, the aim was to identify common locations (“hotspots”) for aggression in bars and examine the association of hotspots with aggression severity and environmental characteristics. Design and Methods Aggression hotspots were identified using narrative descriptions and data recorded on premises’ floor plans for 1057 incidents of aggression collected in the Safer Bars evaluation. Hierarchical Linear Modeling was used to identify bar-level and night-level characteristics associated with each hotspot. Results The most common location for aggression was the dance floor (20.0% of incidents) or near the dance floor (11.5%), followed by near the serving bar (15.7%), at tables (13.1%), aisles, hallways and other areas of movement (6.2%), entrance (4.5%) and the pool playing area (4.1%). Hotspots were predicted mainly by bar-level characteristics, with dance floor aggression associated with crowded bars, a high proportion of female and young patrons, lots of sexual activity, a large number of patrons and staff, security staff present, better monitoring and coordination by staff, and people hanging around at closing. Incidents at tables and pool tables tended to occur in bars with the opposite characteristics. Nightly variations in patron intoxication and rowdiness were associated with aggression at tables while variations in crowding and sexual activity were associated with aggression in areas of movement. Incidents outside tended to be more severe. Discussion and Conclusions Each aggression location and their associated environments have somewhat different implications for staff training, premises design, policy and prevention. PMID:22050319

  1. 'Hotspots' for aggression in licensed drinking venues.

    PubMed

    Graham, Kathryn; Bernards, Sharon; Osgood, D Wayne; Wells, Samantha

    2012-06-01

    In order to better understand the social context of barroom aggression, the aim was to identify common locations ('hotspots') for aggression in bars and examine the association of hotspots with aggression severity and environmental characteristics. Aggression hotspots were identified using narrative descriptions and data recorded on premises' floor plans for 1057 incidents of aggression collected in the Safer Bars evaluation. Hierarchical Linear Modelling was used to identify bar-level and night-level characteristics associated with each hotspot. The most common location for aggression was the dance floor (20.0% of incidents) or near the dance floor (11.5%), followed by near the serving bar (15.7%), at tables (13.1%), aisles, hallways and other areas of movement (6.2%), entrance (4.5%) and the pool playing area (4.1%). Hotspots were predicted mainly by bar-level characteristics, with dance floor aggression associated with crowded bars, a high proportion of female and young patrons, lots of sexual activity, a large number of patrons and staff, security staff present, better monitoring and coordination by staff, and people hanging around at closing. Incidents at tables and pool tables tended to occur in bars with the opposite characteristics. Nightly variations in patron intoxication and rowdiness were associated with aggression at tables while variations in crowding and sexual activity were associated with aggression in areas of movement. Incidents outside tended to be more severe. Each aggression location and their associated environments have somewhat different implications for staff training, premises design, policy and prevention. © 2011 Australasian Professional Society on Alcohol and other Drugs.

  2. "Blurred lines?" Sexual aggression and barroom culture.

    PubMed

    Graham, Kathryn; Bernards, Sharon; Wayne Osgood, D; Abbey, Antonia; Parks, Michael; Flynn, Andrea; Dumas, Tara; Wells, Samantha

    2014-05-01

    Meeting potential sexual/romantic partners for mutual pleasure is one of the main reasons young adults go to bars. However, not all sexual contacts are positive and consensual, and aggression related to sexual advances is a common experience. Sometimes such aggression is related to misperceptions in making and receiving sexual advances while other times aggression reflects intentional harassment or other sexually aggressive acts. This study uses objective observational research to assess quantitatively gender of initiators and targets and the extent that sexual aggression involves intentional aggression by the initiator, the nature of responses by targets, and the role of third parties and intoxication. We analyzed 258 aggressive incidents involving sexual advances observed as part of a larger study on aggression in large capacity bars and clubs, using variables collected as part of the original research (gender, intoxication, intent) and variables coded from narrative descriptions (invasiveness, persistence, targets' responses, role of third parties). Hierarchical linear modeling analyses were used to account for nesting of incidents in evening and bars. Ninety percent of incidents involved male initiators and female targets, with almost all incidents involving intentional or probably intentional aggression. Targets mostly responded nonaggressively, usually using evasion. Staff rarely intervened; patron third parties intervened in 21% of incidents, usually to help the target but sometimes to encourage the initiator. initiators' level of invasiveness was related to intoxication of the targets, but not their own intoxication, suggesting intoxicated women were being targeted. Sexual aggression is a major problem in bars often reflecting intentional sexual invasiveness and unwanted persistence rather than misperceptions in sexual advances. Prevention needs to focus on addressing masculinity norms of male patrons and staff who support sexual aggression and better management of the highly sexualized and sexist environments of most bars. Copyright © 2014 by the Research Society on Alcoholism.

  3. Simultaneous use of alcohol with methamphetamine but not ecstasy linked with aggression among young adult stimulant users.

    PubMed

    Leslie, Ellen M; Smirnov, Andrew; Cherney, Adrian; Wells, Helene; Legosz, Margot; Kemp, Robert; Najman, Jake M

    2017-07-01

    Illicit stimulants are often combined with alcohol in nightlife entertainment districts, an environment where aggressive behaviour commonly occurs. While alcohol and methamphetamine use are each associated with aggressive behaviour, relatively little is known about the impact of the combined use of alcohol and amphetamine-type stimulants (i.e., ecstasy [MDMA] and methamphetamine) on aggression. Analysis of longitudinal data from a population-based sample of Australian young adult amphetamine-type stimulant users (n=248) to examine: (a) prevalence and timing of simultaneous alcohol and amphetamine-type stimulant use and (b) predictors of ecstasy- and methamphetamine-related aggression and hostility. Prediction models of ecstasy- and methamphetamine-related aggression and hostility were developed using multivariate logistic regression. Simultaneous alcohol consumption and amphetamine-type stimulant use was prevalent, with drinking generally occurring before consuming amphetamine-type stimulants and while 'high'. Methamphetamine-related aggression and hostility was significantly associated with recurrent risky simultaneous methamphetamine and alcohol use (Adjusted Odds Ratio [AOR] 2.74, 95% CI 1.09-6.89), a high frequency and increasing use methamphetamine trajectory (AOR 7.23, 95% CI 1.27-41.03), and high trait aggression (AOR 5.78, 95% CI 2.53-13.20). In contrast, only trait aggression (moderate: AOR 3.01, 95% CI 1.55-5.84; high: AOR 5.02, 95% CI 2.38-10.61) was associated with ecstasy-related aggression and hostility. These findings indicate a link between risky patterns of simultaneous alcohol and methamphetamine use and methamphetamine-related aggression and hostility, independent of separate use of alcohol, methamphetamine and cannabis, trait aggression, psychosis, and gender. The policy challenges of amphetamine-type stimulant and alcohol use require a targeted, multidisciplinary approach. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Brain Serotonin Receptors and Transporters: Initiation vs. Termination of Escalated Aggression

    PubMed Central

    Takahashi, Aki; Quadros, Isabel M.; de Almeida, Rosa M. M.; Miczek, Klaus A.

    2013-01-01

    Rationale Recent findings have shown a complexly regulated 5-HT system as it is linked to different kinds of aggression. Objective We focus on (1) phasic and tonic changes of 5-HT and (2) state and trait of aggression, and emphasize the different receptor subtypes, their role in specific brain regions, feed-back regulation and modulation by other amines, acids and peptides. Results New pharmacological tools differentiate the first three 5-HT receptor families and their modulation by GABA, glutamate and CRF. Activation of 5-HT1A, 5-HT1B and 5-HT2A/2C receptors in mesocorticolimbic areas, reduce species-typical and other aggressive behaviors. In contrast, agonists at 5-HT1A and 5-HT1B receptors in the medial prefrontal cortex or septal area can increase aggressive behavior under specific conditions. Activation of serotonin transporters reduce mainly pathological aggression. Genetic analyses of aggressive individuals have identified several molecules that affect the 5-HT system directly (e.g., Tph2, 5-HT1B, 5-HT transporter, Pet1, MAOA) or indirectly (e.g., Neuropeptide Y, αCaMKII, NOS, BDNF). Dysfunction in genes for MAOA escalates pathological aggression in rodents and humans, particularly in interaction with specific experiences. Conclusions Feedback to autoreceptors of the 5-HT1 family and modulation via heteroreceptors are important in the expression of aggressive behavior. Tonic increase of the 5-HT2 family expression may cause escalated aggression, whereas the phasic increase of 5-HT2 receptors inhibits aggressive behaviors. Polymorphisms in the genes of 5-HT transporters or rate-limiting synthetic and metabolic enzymes of 5-HT modulate aggression, often requiring interaction with the rearing environment. PMID:20938650

  5. Social behavior and aggressive problems of cats.

    PubMed

    Crowell-Davis, S L; Barry, K; Wolfe, R

    1997-05-01

    Cats form social groups in which individuals recognize each other, and the cohesiveness of the group is maintained by a variety of amicable behaviors. Agonistic behavior may occur between group members and between group members and nongroup members. Within the domestic environment, agonistic behavior may become a problem when it is directed at housemates or humans. Differential diagnosis and treatment of various problems of aggressive behavior are discussed.

  6. Gender stereotypes, aggression, and computer games: an online survey of women.

    PubMed

    Norris, Kamala O

    2004-12-01

    Computer games were conceptualized as a potential mode of entry into computer-related employment for women. Computer games contain increasing levels of realism and violence, as well as biased gender portrayals. It has been suggested that aggressive personality characteristics attract people to aggressive video games, and that more women do not play computer games because they are socialized to be non-aggressive. To explore gender identity and aggressive personality in the context of computers, an online survey was conducted on women who played computer games and women who used the computer but did not play computer games. Women who played computer games perceived their online environments as less friendly but experienced less sexual harassment online, were more aggressive themselves, and did not differ in gender identity, degree of sex role stereotyping, or acceptance of sexual violence when compared to women who used the computer but did not play video games. Finally, computer gaming was associated with decreased participation in computer-related employment; however, women with high masculine gender identities were more likely to use computers at work.

  7. [The BASYS observation system for the analysis of aggressive behavior in classroom-settings].

    PubMed

    Wettstein, Alexander

    2012-01-01

    Educational or therapeutic measures of aggressive student behavior are often based on the judgments of teachers. However, empirical studies show that the objectivity of these judgments is generally low. In order to assess aggressive behavior in classroom settings, we developed a context-sensitive observational system. The observation system exists in a version for teachers in action as well as a version for the uninvolved observer. The teacher version allows categorizing aggressive behavior while teaching. The aim is to differentiate the perception and the judgments of teachers, so that the judgments can serve as trustable diagnostic information. The version for an independent observer, in addition, contains categories to collect information about the context in which aggressions take place. The behavior observation system was tested in four field-studies in regular and special classes. The empirical results show that, after training, teachers were able to make objective observations, and that aggressive behavior depends to a large extent on situational factors. The system allows identification of problematic people-environment relationships and the derivation of intervention measures.

  8. Evaluation of dry technology for removal of pellicle adhesive residue on advanced optical reticles

    NASA Astrophysics Data System (ADS)

    Paracha, Shazad; Bekka, Samy; Eynon, Benjamin; Choi, Jaehyuck; Balooch, Mehdi; Varghese, Ivin; Hopkins, Tyler

    2013-09-01

    The fast pace of MOSFET scaling is accelerating the introduction of smaller technology nodes to extend CMOS beyond 20nm as required by Moore's law. To meet these stringent requirements, the industry is seeing an increase in the number of critical layers per reticle set as it move to lower technology nodes especially in a high volume manufacturing operation. These requirements are resulting in reticles with higher feature densities, smaller feature sizes and highly complex Optical Proximity Correction (OPC), built with using new absorber and pellicle materials. These rapid changes are leaving a gap in maintaining these reticles in a fab environment, for not only haze control but also the functionality of the reticle. The industry standard of using wet techniques (which uses aggressive chemicals, like SPM, and SC1) to repel reticles can result in damage to the sub-resolution assist features (SRAF's), create changes to CD uniformity and have potential for creating defects that require other means of removal or repair. Also, these wet cleaning methods in the fab environment can create source for haze growth. Haze can be controlled by: 1) Chemical free (dry) reticle cleaning, 2) In-line reticle inspection in fab, and 3) Manage the environment where reticles are stored. In this paper we will discuss a dry technique (chemical free) to remove pellicle adhesive residue from advanced optical reticles. Samsung Austin Semiconductors (SAS), jointly worked with Eco-Snow System (a division of RAVE N.P., Inc.) to evaluate the use of Dry Reactive Gas (DRG) technique to remove pellicle adhesive residue on reticles. This technique can significantly reduce the impact to the critical geometry in active array of the reticle, resulting in preserving the reticle performance level seen at wafer level. The paper will discuss results on the viability of this technique used on advanced reticles.

  9. Durability tests of a fiber optic corrosion sensor.

    PubMed

    Wan, Kai Tai; Leung, Christopher K Y

    2012-01-01

    Steel corrosion is a major cause of degradation in reinforced concrete structures, and there is a need to develop cost-effective methods to detect the initiation of corrosion in such structures. This paper presents a low cost, easy to use fiber optic corrosion sensor for practical application. Thin iron film is deposited on the end surface of a cleaved optical fiber by sputtering. When light is sent into the fiber, most of it is reflected by the coating. If the surrounding environment is corrosive, the film is corroded and the intensity of the reflected signal drops significantly. In previous work, the sensing principle was verified by various experiments in laboratory and a packaging method was introduced. In this paper, the method of multiplexing several sensors by optical time domain reflectometer (OTDR) and optical splitter is introduced, together with the interpretation of OTDR results. The practical applicability of the proposed sensors is demonstrated in a three-year field trial with the sensors installed in an aggressive marine environment. The durability of the sensor against chemical degradation and physical degradation is also verified by accelerated life test and freeze-thaw cycling test, respectively.

  10. Studies of detailed biofilm characterization on fly ash concrete in comparison with normal and superplasticizer concrete in seawater environments.

    PubMed

    Vishwakarmaa, Vinita; George, R P; Ramachandran, D; Anandkumar, B; Mudalib, U Kamachi

    2014-01-01

    In cooling water systems, many concrete structures in the form of tanks, pillars and reservoirs that come in contact with aggressive seawater are being deteriorated by chemical and biological factors. The nuclear industry has decided to partially replace the Portland cement with appropriate pozzolans such as fly ash, which could densify the matrix and make the concrete impermeable. Three types of concrete mixes, viz., normal concrete (NC), concrete with fly ash and superplasticizer (FA) and concrete with only superplasticizer (SP) were fabricated for short- and long-term exposure studies and for screening out the better concrete in seawater environments. Biofilm characterization studies and microscopic studies showed excellent performance of FA concrete compared to the other two. Laboratory exposure studies in pure cultures of Thiobacillus thiooxidans and Fusarium oxysporum were demonstrated for the inhibition of microbial growth on fly ash. Epifluorescence and scanning electron microscopic studies supported the better performance of the FA specimen. Thus, the present study clearly showed that FA concrete is less prone to biofilm formation and biodeterioration.

  11. The effect of early life experience, environment, and genetic factors on spontaneous home-cage aggression-related wounding in male C57BL/6 mice.

    PubMed

    Gaskill, Brianna N; Stottler, Aurora M; Garner, Joseph P; Winnicker, Christina W; Mulder, Guy B; Pritchett-Corning, Kathleen R

    2017-03-22

    Aggression is a major welfare issue in mice, particularly when mice unfamiliar to each other are first placed in cages, as happens on receipt from a vendor, and following cage cleaning. Injuries from aggression are the second leading cause of unplanned euthanasia in mice, following ulcerative dermatitis. Commonly employed strategies for reducing aggression-related injury are largely anecdotal, and may even be counterproductive. Here we report a series of experiments testing potential explanations and interventions for post-shipping aggression-related injuries in C57BL/6 mice. First, we examined the effects of weaning: testing whether manipulating weaning age reduced aggression-related injuries, and if repeated mixing of weaned mice before shipping increased these injuries. Contrary to our predictions, repeated mixing did not increase post-shipping injurious aggression, and early weaning reduced aggression-related injuries. Second, we examined potential post-shipping interventions: testing whether lavender essential oil applied to the cage reduced aggression-related injuries, and whether a variety of enrichments decreased injurious aggression. Again, contrary to predictions, lavender increased wounding, and none of the enrichments reduced it. However, consistent with the effects of weaning age in the first experiment, cages with higher mean body weight showed elevated levels of aggression-related wounding. Finally, we tested whether C57BL/6 substrains and identification methods affected levels of intra-cage wounding from aggression. We found no effect of strain, but cages where mice were ear-notched for identification showed higher levels of wounding than cages where mice were tail-tattooed. Overall, these results emphasize the multifactorial nature of home-cage injurious aggression, and the importance of testing received wisdom when it comes to managing complex behavioral and welfare problems. In terms of practical recommendations to reduce aggressive wounding in the home cage, tail tattooing is recommended over ear notching and late weaning should be avoided.

  12. Dual use of distributed remote sensing satellites

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

    Canavan, G.H.

    1992-12-02

    Satellites can serve both defense and the environment, simultaneously monitoring preparations for aggression, the environment, pollution, and natural disasters. These applications have been discussed extensively in international meetings, which have produced specific projects for cooperation and growing acceptance of dual-use concepts.

  13. Dual use of distributed remote sensing satellites

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

    Canavan, G.H.

    1993-03-01

    Satellites can serve both defense and the environment, simultaneously monitoring preparations for aggression, the environment, pollution, and natural disasters. These applications have been discussed extensively in international meetings, which have produced specific projects for cooperation and growing acceptance of dual-use concepts.

  14. Dual use of distributed remote sensing satellites

    NASA Astrophysics Data System (ADS)

    Canavan, G. H.

    1992-12-01

    Satellites can serve both defense and the environment, simultaneously monitoring preparations for aggression, the environment, pollution, and natural disasters. These applications have been discussed extensively in international meetings, which have produced specific projects for cooperation and growing acceptance of dual-use concepts.

  15. Performance of high performance concrete (HPC) in low pH and sulfate environment : [technical summary].

    DOT National Transportation Integrated Search

    2013-01-01

    High-performance concrete (HPC) refers to any concrete formulation with enhanced characteristics, compared to normal concrete. One might think this refers to strength, but in Florida, the HPC standard emphasizes withstanding aggressive environments, ...

  16. Aggressive Behavior between Siblings and the Development of Externalizing Problems: Evidence from a Genetically Sensitive Study

    PubMed Central

    Natsuaki, Misaki N.; Ge, Xiaojia; Reiss, David; Neiderhiser, Jenae M.

    2011-01-01

    This study investigated the prospective links between sibling aggression and the development of externalizing problems using a multilevel modeling approach with a genetically sensitive design. The sample consisted of 780 adolescents (390 sibling pairs) who participated in two waves of the Nonshared Environment for Adolescent Development (NEAD) project. Sibling pairs with varying degree of genetic relatedness, including monozygotic twins, dizygotic twins, full siblings, half siblings, and genetically unrelated siblings, were included. The results showed that sibling aggression at Time 1 was significantly associated with the focal child’s externalizing problems at Time 2 after accounting for the intra-class correlations between siblings. Sibling aggression remained significant in predicting subsequent externalizing problems even after controlling for the levels of pre-existing externalizing problems and mothers’ punitive parenting. This pattern of results was fairly robust across models using different informants. The findings provide converging evidence for the unique contribution of sibling aggression in understanding changes in externalizing problems during adolescence. PMID:19586176

  17. Child exposure to serious life events, COMT, and aggression: Testing differential susceptibility theory.

    PubMed

    Hygen, Beate Wold; Belsky, Jay; Stenseng, Frode; Lydersen, Stian; Guzey, Ismail Cuneyt; Wichstrøm, Lars

    2015-08-01

    Both genetic and environmental factors contribute to individual differences in aggression. Catechol-O-methyltransferase Val158Met (COMT), a common, functional polymorphism, has been implicated in aggression and aggression traits, as have childhood experiences of adversity. It is unknown whether these effects are additive or interactional and, in the case of interaction, whether they conform to a diathesis-stress or differential susceptibility model. We examined Gene × Environment interactions between COMT and serious life events on measures of childhood aggression and contrasted these 2 models. The sample was composed of community children (N = 704); 355 were boys, and the mean age was 54.8 months (SD = 3.0). The children were genotyped for COMT rs4680 and assessed for serious life events and by teacher-rated aggression. Regression analysis showed no main effects of COMT and serious life events on aggression. However, a significant interactive effect of childhood serious life events and COMT genotype was observed: Children who had faced many serious life events and were Val homozygotes exhibited more aggression (p = .02) than did their Met-carrying counterparts. Notably, in the absence of serious life events, Val homozygotes displayed significantly lower aggression scores than did Met carriers (p = .03). When tested, this constellation of findings conformed to the differential susceptibility hypothesis: In this case, Val homozygotes are more malleable to the effect of serious life events on aggression and not simply more vulnerable to the negative effect of having experienced many serious life events. (c) 2015 APA, all rights reserved).

  18. Maternal rank influences the outcome of aggressive interactions between immature chimpanzees

    PubMed Central

    Markham, A. Catherine; Lonsdorf, Elizabeth V.; Pusey, Anne E.; Murray, Carson M.

    2015-01-01

    For many long-lived mammalian species, extended maternal investment has a profound effect on offspring integration in complex social environments. One component of this investment may be aiding young in aggressive interactions, which can set the stage for offspring social position later in life. Here we examined maternal effects on dyadic aggressive interactions between immature (<12 years) chimpanzees. Specifically, we tested whether relative maternal rank predicted the probability of winning an aggressive interaction. We also examined maternal responses to aggressive interactions to determine whether maternal interventions explain interaction outcomes. Using a 12-year behavioural data set (2000–2011) from Gombe National Park, Tanzania, we found that relative maternal rank predicted the probability of winning aggressive interactions in male–male and male–female aggressive interactions: offspring were more likely to win if their mother outranked their opponent’s mother. Female–female aggressive interactions occurred infrequently (two interactions), so could not be analysed. The probability of winning was also higher for relatively older individuals in male–male interactions, and for males in male–female interactions. Maternal interventions were rare (7.3% of 137 interactions), suggesting that direct involvement does not explain the outcome for the vast majority of aggressive interactions. These findings provide important insight into the ontogeny of aggressive behaviour and early dominance relationships in wild apes and highlight a potential social advantage for offspring of higher-ranking mothers. This advantage may be particularly pronounced for sons, given male philopatry in chimpanzees and the potential for social status early in life to translate more directly to adult rank. PMID:25624528

  19. Behavioural indicators of motives for barroom aggression: implications for preventing bar violence.

    PubMed

    Graham, Kathryn; Bernards, Sharon; Wells, Samantha; Osgood, D Wayne; Abbey, Antonia; Felson, Richard B; Saltz, Robert F

    2011-09-01

    To develop new strategies for preventing violence in high-risk licensed premises, we identify behavioural indicators of apparent motives for aggression in these settings and outline the implications of different motivations for prevention. The four types of motives for aggressive or coercive acts defined by the theory of coercive actions framed the research: gaining compliance, expressing grievances/restoring justice, attaining a favourable social identity and pursuing fun/excitement. Incidents of aggression from the Safer Bars evaluation research were analysed to identify behavioural indicators of each motivation. Compliance-motivated aggression typically takes the form of unwanted social overtures, third party intervention to stop conflicts or staff rule enforcement. Prevention strategies include keeping the aggressor's focus on compliance to avoid provoking grievance and identity motives that are likely to escalate aggression. Grievance motives are typically elicited by perceived wrongdoing and therefore prevention should focus on eliminating sources of grievances and adopting policies/practices to resolve grievances peacefully. Social identity motives are endemic to many drinking establishments especially among male patrons and staff. Prevention involves reducing identity cues in the environment, hiring staff who do not have identity concerns, and training staff to avoid provoking identity concerns. Aggression motivated by fun/excitement often involves low-level aggression where escalation can be prevented by avoiding grievances and attacks on identity. Knowledge of behavioural indicators of motives can be used to enhance staff hiring and training practices, reduce environmental triggers for aggression, and develop policies to reduce motivation for aggression. © 2011 Australasian Professional Society on Alcohol and other Drugs.

  20. Alcohol-related aggression-social and neurobiological factors.

    PubMed

    Beck, Anne; Heinz, Andreas

    2013-10-01

    Alcohol-related aggression and violence are a widespread cause of personal suffering with high socioeconomic costs. In 2011, nearly one in three violent acts in Germany was committed under the influence of alcohol (31.8%). The link between alcohol consumption and aggression is promoted by various interacting factors. In this review, based on a selective search for pertinent literature in PubMed, we analyze and summarize information from original articles, reviews, and book chapters about alcohol and aggression and discuss the neurobiological basis of aggressive behavior. Aggression is promoted both by the cognitive deficits arising in connection with acute or chronic alcohol use and by prior experience of violence in particular situations where alcohol was drunk. Only a minority of persons who drink alcohol become aggressive. On the other hand, alcohol abuse and dependence together constitute the second most commonly diagnosed cause of suicide (15-43%). Current research indicates that the individual tendency toward alcohol-induced aggression depends not just on neurobiological factors, but also on personal expectations of the effects of alcohol, on prior experience of violent conflicts, and on the environmental conditions of early childhood, especially social exclusion and discrimination. Gene-environment interactions affecting the serotonergic and other neurotransmitter systems play an important role. Potential (but not yet adequately validated) therapeutic approaches involve reinforcing cognitive processes or pharmacologically modulating serotonergic neurotransmission (and other target processes). Alcohol-related aggression has manifold social and neurobiological causes. Specific treatments must be tested in controlled trials.

  1. Aggression and Rule-breaking: Heritability and stability of antisocial behavior problems in childhood and adolescence

    PubMed Central

    Niv, Sharon; Tuvblad, Catherine; Raine, Adrian; Baker, Laura A.

    2013-01-01

    Purpose This twin study examined the structure of genetic and environmental influences on aggression and rule-breaking in order to examine change and stability across the span of childhood to mid-adolescence. Methods Behavioral assessments were conducted at two time points: age 9–10 years and 14–15 years. Using behavioral genetics biometric modeling, the longitudinal structure of influences was investigated. Results Aggression and rule-breaking were found to be influenced by a latent common factor of antisocial behavior (ASB) within each wave of data collection. The childhood-age common factor of ASB was influenced by 41% genetics, 40% shared environment and 19% nonshared environment. In adolescence, 41% of influences on the common factor were novel and entirely genetic, while the remainder of influences were stable across time. Additionally, both aggression and rule-breaking within each wave were found to have unique influences not common across subscales or across waves, highlighting specificity of influences on different problem behaviors at both ages. Conclusions This research sheds light on the commonality of influences on etiology of different forms of antisocial behavior, and suggests future directions for research into intervention for antisocial behavior problems in youth, such as investigation of adolescence-specific environmental influences on the development of antisocial behavior problems. PMID:24347737

  2. Understanding school climate, aggression, peer victimization, and bully perpetration: contemporary science, practice, and policy.

    PubMed

    Espelage, Dorothy L; Low, Sabina K; Jimerson, Shane R

    2014-09-01

    Existing scholarship suggests that classroom practices, teacher attitudes, and the broader school environment play a critical role in understanding the rates of student reports of aggression, bullying, and victimization as well as correlated behaviors. A more accurate understanding of the nature, origins, maintenance, and prevalence of bullying and other aggressive behavior requires consideration of the broader social ecology of the school community. However, studies to date have predominantly been cross-sectional in nature, or have failed to reflect the social-ecological framework in their measurement or analytic approach. Thus, there have been limited efforts to parse out the relative contribution of student, classroom, and organizational-level factors. This special topic section emphasizes a departure from a focus on student attitudes and behaviors, to a social-contextual approach that appreciates how much features of the school environment can mitigate or perpetuate aggression. This collection of articles reflects innovative and rigorous approaches to further our understanding of climate, and has implications for theory, measurement, prevention, and practice. These studies highlight the influence of school climate on mental health, academic achievement, and problem behavior, and will hopefully stimulate interest in and further scholarship on this important topic. PsycINFO Database Record (c) 2014 APA, all rights reserved.

  3. Social learning requires plasticity enhanced by fluoxetine through prefrontal Bdnf-TrkB signaling to limit aggression induced by post-weaning social isolation

    PubMed Central

    Umemori, Juzoh; Tóth, Máté; Biró, László; Miskolczi, Christina; Balázsfi, Diána; Zelena, Dóra; Castrén, Eero

    2017-01-01

    Escalated or abnormal aggression induced by early adverse experiences is a growing issue of social concern and urges the development of effective treatment strategies. Here we report that synergistic interactions between psychosocial and biological factors specifically ameliorate escalated aggression induced by early adverse experiences. Rats reared in isolation from weaning until early adulthood showed abnormal forms of aggression and social deficits that were temporarily ameliorated by re-socialization, but aggression again escalated in a novel environment. We demonstrate that when re-socialization was combined with the antidepressant fluoxetine, which has been shown to reactivate juvenile-like state of plasticity, escalated aggression was greatly attenuated, while neither treatment alone was effective. Early isolation induced a permanent, re-socialization resistant reduction in Bdnf expression in the amygdala and the infralimbic cortex. Only the combined treatment of fluoxetine and re-socialization was able to recover Bdnf expression via epigenetic regulation. Moreover, the behavior improvement after the combined treatment was dependent on TrkB activity. Combined treatment specifically strengthened the input from the ventral hippocampus to the mPFC suggesting that this pathway is an important mediator of the beneficial behavioral effects of the combined psychosocial and pharmacological treatment of abnormal aggression. Our findings suggest that synergy between pharmacological induction of plasticity and psychosocial rehabilitation could enhance the efficacy of therapies for pathological aggression. PMID:28685757

  4. High-Temperature Self-Healing and Re-Adhering Geothermal Well Cement Composites

    NASA Astrophysics Data System (ADS)

    Pyatina, T.; Sugama, T.; Boodhan, Y.; Nazarov, L.

    2017-12-01

    Self-healing cementitious materials are particularly attractive for the cases where damaged areas are difficult to locate and reach. High-temperature geothermal wells with aggressive environments impose most difficult conditions on cements that must ensure durable zonal isolation under repeated thermal, chemical and mechanical stresses. The present work evaluates matrix and carbon steel (CS) - cement interface self-healing and re-adhering properties of various inorganic cementitious composites under steam, alkali carbonate or brine environments at 270-300oC applicable to geothermal wells. The composite materials included blends based on Ordinary Portland Cement (OPC) and natural zeolites and alkali or phosphate activated composites of Calcium Aluminate Cement (CAC) with fly ash, class F. Class G cement blend with crystalline silica was used as a baseline. Compressive-strength and bond-strength recoveries were examined to evaluate self-healing and re-adhering properties of the composites after repeated crush tests followed by 5-day healing periods in these environments. The optical and scanning electron microscopes, X-ray diffraction, Fourier Transform infrared, Raman spectroscopy and EDX measurements were used to identify phases participating in the strengths recoveries and cracks filling processes. Amorphous silica-rich- and small-size crystalline phases played an important role in the healing of the tested composites in all environments. Possible ways to enhance self-healing properties of cementitious composites under conditions of geothermal wells were identified.

  5. [Study review of biological, social and environmental factors associated with aggressive behavior].

    PubMed

    Mendes, Deise Daniela; Mari, Jair de Jesus; Singer, Marina; Barros, Gustavo Machado; Mello, Andréa F

    2009-10-01

    To study the risk factors related to the development of aggressive behavior. A search was carried out in two electronic databases, Medline and SciElo by retrospective studies, longitudinal and review that assessed risk factors for the development of aggressive behavior. There were selected 11 longitudinal studies (8 prospective and 3 case-control studies) and a cross sectional study that evaluated the risk factors and socio-biological related to aggressive behavior. Five studies have evaluated gene expression, five evaluated exposure to tobacco, alcohol and cocaine in the prenatal period, one evaluated the effect of early malnutrition on the development of aggressive behavior and one assessed the impact of child maltreatment. The main biological factors were: genetic (low expression of the monoamine oxidase gene and serotonin transporter gene, variations in transporter and dopamine receptor genes), exposure to substances during intrauterine development (tobacco, alcohol and cocaine) and nutrition (malnutrition). The main environmental factors were: child abuse, poverty, crime and antisocial behavior in childhood, while the highest level of evidence was related to early neglect. The interaction between biological and environmental factors can be catalyzed by a hostile environment, increasing the risk for the development of aggressive behavior.

  6. Identifying key factors associated with aggression on acute inpatient psychiatric wards.

    PubMed

    Bowers, Len; Allan, Teresa; Simpson, Alan; Jones, Julia; Van Der Merwe, Marie; Jeffery, Debra

    2009-04-01

    Aggressive behaviour is a critical issue for modern acute psychiatric services, not just because of the adverse impact it has on patients and staff, but also because it puts a financial strain on service providers. The aim of this study was to assess the relationship of patient violence to other variables: patient characteristics, features of the service and physical environment, patient routines, staff factors, the use of containment methods, and other patient behaviours. A multivariate cross sectional design was utilised. Data were collected for a six month period on 136 acute psychiatric wards in 26 NHS Trusts in England. Multilevel modelling was conducted to ascertain those factors most strongly associated with verbal aggression, aggression toward objects, and physical aggression against others. High levels of aggression were associated with a high proportion of patients formally detained under mental health legislation, high patient turnover, alcohol use by patients, ward doors being locked, and higher staffing numbers (especially qualified nurses). The findings suggest that the imposition of restrictions on patients exacerbates the problem of violence, and that alcohol management strategies may be a productive intervention. Insufficient evidence is available to draw conclusions about the nature of the link between staffing numbers and violence.

  7. The effects of a multiyear universal social-emotional learning program: The role of student and school characteristics.

    PubMed

    2010-04-01

    This article examines the impact of a universal social-emotional learning program, the Fast Track PATHS (Promoting Alternative Thinking Strategies) curriculum and teacher consultation, embedded within the Fast Track selective prevention model. The longitudinal analysis involved 2,937 children of multiple ethnicities who remained in the same intervention or control schools for Grades 1, 2, and 3. The study involved a clustered randomized controlled trial involving sets of schools randomized within 3 U.S. locations. Measures assessed teacher and peer reports of aggression, hyperactive-disruptive behaviors, and social competence. Beginning in first grade and through 3 successive years, teachers received training and support and implemented the PATHS curriculum in their classrooms. The study examined the main effects of intervention as well as how outcomes were affected by characteristics of the child (baseline level of problem behavior, gender) and by the school environment (student poverty). Modest positive effects of sustained program exposure included reduced aggression and increased prosocial behavior (according to both teacher and peer report) and improved academic engagement (according to teacher report). Peer report effects were moderated by gender, with significant effects only for boys. Most intervention effects were moderated by school environment, with effects stronger in less disadvantaged schools, and effects on aggression were larger in students who showed higher baseline levels of aggression. A major implication of the findings is that well-implemented multiyear social-emotional learning programs can have significant and meaningful preventive effects on the population-level rates of aggression, social competence, and academic engagement in the elementary school years. (c) 2010 APA, all rights reserved.

  8. Organization and evolution of hsp70 clusters strikingly differ in two species of Stratiomyidae (Diptera) inhabiting thermally contrasting environments.

    PubMed

    Garbuz, David G; Yushenova, Irina A; Zatsepina, Olga G; Przhiboro, Andrey A; Bettencourt, Brian R; Evgen'ev, Michael B

    2011-03-22

    Previously, we described the heat shock response in dipteran species belonging to the family Stratiomyidae that develop in thermally and chemically contrasting habitats including highly aggressive ones. Although all species studied exhibit high constitutive levels of Hsp70 accompanied by exceptionally high thermotolerance, we also detected characteristic interspecies differences in heat shock protein (Hsp) expression and survival after severe heat shock. Here, we analyzed genomic libraries from two Stratiomyidae species from thermally and chemically contrasting habitats and determined the structure and organization of their hsp70 clusters. Although the genomes of both species contain similar numbers of hsp70 genes, the spatial distribution of hsp70 copies differs characteristically. In a population of the eurytopic species Stratiomys singularior, which exists in thermally variable and chemically aggressive (hypersaline) conditions, the hsp70 copies form a tight cluster with approximately equal intergenic distances. In contrast, in a population of the stenotopic Oxycera pardalina that dwells in a stable cold spring, we did not find hsp70 copies in tandem orientation. In this species, the distance between individual hsp70 copies in the genome is very large, if they are linked at all. In O. pardalina we detected the hsp68 gene located next to a hsp70 copy in tandem orientation. Although the hsp70 coding sequences of S. singularior are highly homogenized via conversion, the structure and general arrangement of the hsp70 clusters are highly polymorphic, including gross aberrations, various deletions in intergenic regions, and insertion of incomplete Mariner transposons in close vicinity to the 3'-UTRs. The hsp70 gene families in S. singularior and O. pardalina evolved quite differently from one another. We demonstrated clear evidence of homogenizing gene conversion in the S. singularior hsp70 genes, which form tight clusters in this species. In the case of the other species, O. pardalina, we found no clear trace of concerted evolution for the dispersed hsp70 genes. Furthermore, in the latter species we detected hsp70 pseudogenes, representing a hallmark of the birth-and-death process.

  9. Organization and evolution of hsp70 clusters strikingly differ in two species of Stratiomyidae (Diptera) inhabiting thermally contrasting environments

    PubMed Central

    2011-01-01

    Background Previously, we described the heat shock response in dipteran species belonging to the family Stratiomyidae that develop in thermally and chemically contrasting habitats including highly aggressive ones. Although all species studied exhibit high constitutive levels of Hsp70 accompanied by exceptionally high thermotolerance, we also detected characteristic interspecies differences in heat shock protein (Hsp) expression and survival after severe heat shock. Here, we analyzed genomic libraries from two Stratiomyidae species from thermally and chemically contrasting habitats and determined the structure and organization of their hsp70 clusters. Results Although the genomes of both species contain similar numbers of hsp70 genes, the spatial distribution of hsp70 copies differs characteristically. In a population of the eurytopic species Stratiomys singularior, which exists in thermally variable and chemically aggressive (hypersaline) conditions, the hsp70 copies form a tight cluster with approximately equal intergenic distances. In contrast, in a population of the stenotopic Oxycera pardalina that dwells in a stable cold spring, we did not find hsp70 copies in tandem orientation. In this species, the distance between individual hsp70 copies in the genome is very large, if they are linked at all. In O. pardalina we detected the hsp68 gene located next to a hsp70 copy in tandem orientation. Although the hsp70 coding sequences of S. singularior are highly homogenized via conversion, the structure and general arrangement of the hsp70 clusters are highly polymorphic, including gross aberrations, various deletions in intergenic regions, and insertion of incomplete Mariner transposons in close vicinity to the 3'-UTRs. Conclusions The hsp70 gene families in S. singularior and O. pardalina evolved quite differently from one another. We demonstrated clear evidence of homogenizing gene conversion in the S. singularior hsp70 genes, which form tight clusters in this species. In the case of the other species, O. pardalina, we found no clear trace of concerted evolution for the dispersed hsp70 genes. Furthermore, in the latter species we detected hsp70 pseudogenes, representing a hallmark of the birth-and-death process. PMID:21426536

  10. Corrosion and scaling in solar heating systems

    NASA Astrophysics Data System (ADS)

    Foresti, R. J., Jr.

    1981-12-01

    Corrosion, as experienced in solar heating systems, is described in simplistic terms to familiarize designers and installers with potential problems and their solutions. The role of a heat transfer fluid in a solar system is briefly discussed, and the choice of an aqueous solution is justified. The complexities of the multiple chemical and physical reactions are discussed in order that uncertainties of corrosion behavior can be anticipated. Some basic theories of corrosion are described, aggressive environments for some common metals are identified, and the role of corrosion inhibitors is delineated. The similarities of thermal and material characteristics of a solor system and an automotive cooling system are discussed. Based on the many years of experience with corrosion in automotive systems, it is recommended that similar antifreezes and corrosion inhibitors should be used in solar systems. The importance of good solar system design and fabrication is stressed and specific characteristics that affect corrosion are identified.

  11. Subcritical crack propagation due to chemical rock weakening: macroscale chemo-plasticity and chemo-elasticity modeling

    NASA Astrophysics Data System (ADS)

    Hueckel, T.; Hu, M.

    2015-12-01

    Crack propagation in a subcritically stressed rock subject to chemically aggressive environment is analyzed and numerically simulated. Chemically induced weakening is often encountered in hydraulic fracturing of low-permeability oil/gas reservoirs and heat reservoirs, during storage of CO2 and nuclear waste corroding canisters, and other circumstances when rock matrix acidizing is involved. Upon acidizing, mineral mass dissolution is substantially enhanced weakening the rock and causing crack propagation and eventually permeability changes in the medium. The crack process zone is modeled mathematically via a chemo-plastic coupling and chemo-elastic coupling model. In plasticity a two-way coupling is postulated between mineral dissolution and a yield limit of rock matrix. The rate of dissolution is described by a rate law, but the mineral mass removal per unit volume is also a function of a variable internal specific surface area, which is in turn affected by the micro-cracking (treated as a plastic strain). The behavior of the rock matrix is modeled as rigid-plastic adding a chemical softening capacity to Cam-Clay model. Adopting the Extended Johnson's approximation of processes around the crack tip, the evolution of the stress field and deformation as a function of the chemically enhanced rock damage is modeled in a simplified way. In addition, chemical reactive transport is made dependent on plastic strain representing micro-cracking. Depending on mechanical and chemical boundary conditions, the area of enhanced chemical softening is near or somewhat away from the crack tip.In elasticity, chemo-mechanical effect is postulated via a chemical volumetric shrinkage strain proportional to mass removal variable, conceived analogously to thermal expansion. Two versions are considered: of constant coefficient of shrinkage and a variable one, coupled to deviatoric strain. Airy Potential approach used for linear elasticity is extended considering an extra term, which is uncoupled or coupled to strain. The later case requires iterations with solution of reactive transport equation. A decrease of stress intensity factor with time of reaction is well reproduced.

  12. Effect of the interaction between oxytocin receptor gene polymorphism (rs53576) and stressful life events on aggression in Chinese Han adolescents.

    PubMed

    Shao, Di; Zhang, Hui-Hui; Long, Zhou-Ting; Li, Jie; Bai, Hua-Yu; Li, Jing-Jing; Cao, Feng-Lin

    2018-06-04

    Accumulating evidence suggests that stressful life events are associated with increased risk for aggressive behavior in adolescents; however, aggressive reactions to life stressors exhibit large individual differences. The present study sought to examine whether the interaction between a single nucleotide polymorphism (SNP [rs53576]) within the oxytocin receptor gene (OXTR) and stressful life events is related to aggression in Chinese Han adolescents. A total of 197 Chinese Han adolescents (14-17 years of age) were included in this study. Aggression was assessed using the 12-item short version of Buss and Perry Aggression Questionnaire. Stressful life events during the past 12 months were assessed using the Adolescent Self-Rating Life Events Checklist. Genomic DNA was extracted from saliva and buccal cells from each individual. Multivariate analysis of variance yielded a significant interaction between OXTR rs53576 SNP and life stress (F = 2.449, p = 0.043, partial η2 = 0.051) and of sex × SNP × life stress (F = 3.144, p = 0.016, partial η2 = 0.064). High life stress during the past 12 months was associated with high levels of physical aggression and hostility in OXTR rs53576 homozygous AA adolescents but not in G-carrier adolescents. In boys, homozygous AA individuals in the high life stress group reported significantly higher levels of physical aggression than participants in the other three groups; the interaction, however, was not significant in girls. This study, which analyzed a specific gene-environment interaction, demonstrated that AA OXTR rs53576 homozygosity may correlate with higher levels of aggression under high life stress conditions with a sample of healthy Chinese Han adolescents. These findings promote the etiological understanding of adolescent aggression, highlighting the complex effect of stressful life events on aggression, and adding evidence supporting the relationship between the oxytocin system and aggressive behavior in adolescents. Copyright © 2018 Elsevier Ltd. All rights reserved.

  13. “Blurred Lines?”1 Sexual Aggression and Barroom Culture

    PubMed Central

    Graham, Kathryn; Bernards, Sharon; Osgood, D. Wayne; Abbey, Antonia; Parks, Michael; Flynn, Andrea; Dumas, Tara; Wells, Samantha

    2014-01-01

    Background Meeting potential sexual/romantic partners for mutual pleasure is one of the main reasons young adults go to bars. However, not all sexual contacts are positive and consensual, and aggression related to sexual advances is a common experience. Sometimes such aggression is related to misperceptions in making and receiving sexual advances while other times aggression reflects intentional harassment or other sexually aggressive acts. The present study uses objective observational research to assess quantitatively gender of initiators and targets and the extent that sexual aggression involves intentional aggression by the initiator, the nature of responses by targets, and the role of third parties and intoxication. Methods We analyzed 258 aggressive incidents involving sexual advances observed as part of a larger study on aggression in large capacity bars and clubs, using variables collected as part of the original research (gender, intoxication, intent) and variables coded from narrative descriptions (invasiveness, persistence, targets’ responses, role of third parties). Hierarchical Linear Modeling (HLM) analyses were used to account for nesting on incidents in evening and bars. Results 90% of incidents involved male initiators and female targets, with almost all incidents involving intentional or probably intentional aggression. Targets mostly responded nonaggressively, usually using evasion to end the incident. Staff rarely intervened; patron third parties intervened in 21% of incidents, usually to help the target but sometimes to encourage the initiator. Initiators’ level of invasiveness was related to intoxication of the targets but not their own intoxication, suggesting intoxicated women were being targeted. Conclusions Sexual aggression is a major problem in bars often reflecting intentional sexual invasiveness and unwanted persistence rather than misperceptions in sexual advances. Prevention needs to focus on addressing masculinity norms of male patrons and staff that support sexual aggression and better management of the highly sexualized and sexist environments of most bars. PMID:24588839

  14. Gene expression and variation in social aggression by queens of the harvester ant Pogonomyrmex californicus.

    PubMed

    Helmkampf, Martin; Mikheyev, Alexander S; Kang, Yun; Fewell, Jennifer; Gadau, Jürgen

    2016-08-01

    A key requirement for social cooperation is the mitigation and/or social regulation of aggression towards other group members. Populations of the harvester ant Pogonomyrmex californicus show the alternate social phenotypes of queens founding nests alone (haplometrosis) or in groups of unrelated yet cooperative individuals (pleometrosis). Pleometrotic queens display an associated reduction in aggression. To understand the proximate drivers behind this variation, we placed foundresses of the two populations into social environments with queens from the same or the alternate population, and measured their behaviour and head gene expression profiles. A proportion of queens from both populations behaved aggressively, but haplometrotic queens were significantly more likely to perform aggressive acts, and conflict escalated more frequently in pairs of haplometrotic queens. Whole-head RNA sequencing revealed variation in gene expression patterns, with the two populations showing moderate differentiation in overall transcriptional profile, suggesting that genetic differences underlie the two founding strategies. The largest detected difference, however, was associated with aggression, regardless of queen founding type. Several modules of coregulated genes, involved in metabolism, immune system and neuronal function, were found to be upregulated in highly aggressive queens. Conversely, nonaggressive queens exhibited a striking pattern of upregulation in chemosensory genes. Our results highlight that the social phenotypes of cooperative vs. solitary nest founding tap into a set of gene regulatory networks that seem to govern aggression level. We also present a number of highly connected hub genes associated with aggression, providing opportunity to further study the genetic underpinnings of social conflict and tolerance. © 2016 John Wiley & Sons Ltd.

  15. Pathology and behaviour in feline medicine: investigating the link between vomeronasalitis and aggression.

    PubMed

    Asproni, Pietro; Cozzi, Alessandro; Verin, Ranieri; Lafont-Lecuelle, Céline; Bienboire-Frosini, Cécile; Poli, Alessandro; Pageat, Patrick

    2016-12-01

    The aim of the study was to investigate if the feline vomeronasal organ (VNO) can be affected by inflammatory lesions and if these changes are associated with behavioural alterations. VNOs from 20 cats were sampled during necropsy, submitted for routine tissue processing and stained with haematoxylin and eosin for histopathological evaluation. For the 20 cats, data on the presence of aggressive behaviours towards cats or humans were collected by questionnaire survey at the point of death. Inflammatory lesions were classified depending on the duration of the process as acute or chronic, both in vomeronasal sensory epithelium (VNSE) and in non-sensory epithelium (NSE). Fisher's exact test was used to compare VNO inflammation with behavioural data. The VNSE was inflamed in 11/20 VNOs (55%) while the NSE was inflamed in 13/20 (65%). Overall, the VNO was affected by inflammation in 14/20 (70%) cats, and all the lesions were classified as chronic. Five out of 20 cats (25%) had documented intraspecific aggressive behaviours and 8/20 (40%) had shown aggression towards humans. Fisher's exact test showed a statistically significant correlation between inflammation of the VNSE and intraspecific aggression (P = 0.038). No statistically correlations were observed between VNSE inflammation and aggression towards humans and between NSE inflammation and aggression towards cats or humans. Our results show, for the first time, the existence of vomeronasalitis in animals and its possible association with intraspecific aggressive behaviours. The inflammatory microenvironment could impair VNSE functionality, causing intraspecific communication alterations, probably through a reduction in chemical communication action and perception. Owing to the pivotal role of the VNO in the social life of cats and other species, this report provides a rationale to further investigate this disease in relation to a variety of behavioural disorders. © The Author(s) 2015.

  16. Resistance of soybean genotypes to Sclerotinia sclerotiorum isolates in different incubation environments

    USDA-ARS?s Scientific Manuscript database

    Sclerotinia sclerotiorum is an important soybean pathogen. The objectives of this study were to evaluate levels of resistance of soybean genotypes to the fungus, and to determine the effects of different incubation environments on host resistance and pathogen aggression. Two experiments were conduct...

  17. Prediction of corrosion rates of water distribution pipelines according to aggressive corrosive water in Korea.

    PubMed

    Chung, W S; Yu, M J; Lee, H D

    2004-01-01

    The drinking water network serving Korea has been used for almost 100 years. Therefore, pipelines have suffered various degrees of deterioration due to aggressive environments. The pipe breaks were caused by in-external corrosion, water hammer, surface loading, etc. In this paper, we focused on describing corrosion status in water distribution pipes in Korea and reviewing some methods to predict corrosion rates. Results indicate that corrosive water of lakes was more aggressive than river water and the winter was more aggressive compared to other seasons. The roughness growth rates of Dongbok lake showed 0.23 mm/year. The high variation of corrosion rates is controlled by the aging pipes and smaller diameter. Also the phenolphthalein test on a cementitious core of cement mortar lined ductile cast iron pipe indicated the pipes over 15 years old had lost 50-100% of their lime active cross sectional area.

  18. Cheating, trade-offs and the evolution of aggressiveness in a natural pathogen population

    PubMed Central

    Barrett, Luke; Bell, Thomas; Dwyer, Greg; Bergelson, Joy

    2011-01-01

    The evolutionary dynamics of pathogens are critically important for disease outcomes, prevalence and emergence. In this study we investigate ecological conditions that may promote the long-term maintenance of virulence polymorphisms in pathogen populations. Recent theory predicts that evolution towards increased virulence can be reversed if less aggressive social ‘cheats’ exploit more aggressive ‘cooperator’ pathogens. However, there is no evidence that social exploitation operates within natural pathogen populations. We show that for the bacterium Pseudomonas syringae, major polymorphisms for pathogenicity are maintained at unexpectedly high frequencies in populations infecting the host Arabidopsis thaliana. Experiments reveal that less aggressive strains substantially increase their growth potential in mixed infections and have a fitness advantage in non-host environments. These results suggest that niche differentiation can contribute to the maintenance of virulence polymorphisms, and that both within-host and between-host growth rates modulate cheating and cooperation in P. syringae populations. PMID:21951910

  19. On-Board Chemical Propulsion Technology

    NASA Technical Reports Server (NTRS)

    Reed, Brian D.

    2004-01-01

    On-board propulsion functions include orbit insertion, orbit maintenance, constellation maintenance, precision positioning, in-space maneuvering, de-orbiting, vehicle reaction control, planetary retro, and planetary descent/ascent. This paper discusses on-board chemical propulsion technology, including bipropellants, monopropellants, and micropropulsion. Bipropellant propulsion has focused on maximizing the performance of Earth storable propellants by using high-temperature, oxidation-resistant chamber materials. The performance of bipropellant systems can be increased further, by operating at elevated chamber pressures and/or using higher energy oxidizers. Both options present system level difficulties for spacecraft, however. Monopropellant research has focused on mixtures composed of an aqueous solution of hydroxl ammonium nitrate (HAN) and a fuel component. HAN-based monopropellants, unlike hydrazine, do not present a vapor hazard and do not require extraordinary procedures for storage, handling, and disposal. HAN-based monopropellants generically have higher densities and lower freezing points than the state-of-art hydrazine and can higher performance, depending on the formulation. High-performance HAN-based monopropellants, however, have aggressive, high-temperature combustion environments and require advances in catalyst materials or suitable non-catalytic ignition options. The objective of the micropropulsion technology area is to develop low-cost, high-utility propulsion systems for the range of miniature spacecraft and precision propulsion applications.

  20. The etiology of social aggression: a nuclear twin family study.

    PubMed

    Slawinski, Brooke L; Klump, Kelly L; Burt, S Alexandra

    2018-04-02

    Social aggression is a form of antisocial behavior in which social relationships and social status are used to damage reputations and inflict emotional harm on others. Despite extensive research examining the prevalence and consequences of social aggression, only a few studies have examined its genetic-environmental etiology, with markedly inconsistent results. We estimated the etiology of social aggression using the nuclear twin family (NTF) model. Maternal-report, paternal-report, and teacher-report data were collected for twin social aggression (N = 1030 pairs). We also examined the data using the classical twin (CT) model to evaluate whether its strict assumptions may have biased previous heritability estimates. The best-fitting NTF model for all informants was the ASFE model, indicating that additive genetic, sibling environmental, familial environmental, and non-shared environmental influences significantly contribute to the etiology of social aggression in middle childhood. However, the best-fitting CT model varied across informants, ranging from AE and ACE to CE. Specific heritability estimates for both NTF and CT models also varied across informants such that teacher reports indicated greater genetic influences and father reports indicated greater shared environmental influences. Although the specific NTF parameter estimates varied across informants, social aggression generally emerged as largely additive genetic (A = 0.15-0.77) and sibling environmental (S = 0.42-0.72) in origin. Such findings not only highlight an important role for individual genetic risk in the etiology of social aggression, but also raise important questions regarding the role of the environment.

  1. Pronounced within-individual plasticity in sperm morphometry across social environments.

    PubMed

    Immler, Simone; Pryke, Sarah R; Birkhead, Tim R; Griffith, Simon C

    2010-06-01

    Sperm morphometry (i.e., size and shape) and function are important determinants of male reproductive success and are thought to be under stabilizing selection. However, recent studies suggest that sperm morphometry can be a phenotypically plastic trait, which can be adjusted to varying conditions. We tested whether different behavioral strategies in aggression between aggressive red and nonaggressive black males of the color polymorphic Gouldian finch (Erythrura gouldiae) can influence sperm morphometry. We show pronounced within-individual phenotypic plasticity in sperm morphometry of male Gouldian finches in three different social environments. Both red and black males placed in intermediate to high competitive environments (high frequency of red males) increased the relative length of their sperm midpiece. By contrast, red males placed in low to intermediate competitive environments (higher frequency of black males) increased the length of the sperm flagellum. Significant changes in stress and sex steroid hormone levels (in response to the competitive environment) appear to influence sperm traits in red but not in black males, suggesting that changes in hormonal levels are not solely responsible for the observed changes in sperm morphometry. These findings imply that males can adjust sperm morphometry across social environments.

  2. PRESENTED 04/05/2006: MERCURY MEASUREMENTS ...

    EPA Pesticide Factsheets

    While traditional methods for determining mercury in solid samples involve the use of aggressive chemicals to dissolve the matrix and the use of other chemicals to properly reduce the mercury to the volatile elemental form, pyrolysis-based analyzers can be used by directly weighing the solid in a sampling boat and initiating the instrumental analysis for total mercury. The research focused on in the subtasks is the development and application of state-of the-art technologies to meet the needs of the public, Office of Water, and ORD in the area of Water Quality. Located In the subtasks are the various research projects being performed in support of this Task and more in-depth coverage of each project. Briefly, each project's objective is stated below.Subtask 1: To integrate state-of-the-art technologies (polar organic chemical integrative samplers, advanced solid-phase extraction methodologies with liquid chromatography/electrospray/mass spectrometry) and apply them to studying the sources and fate of a select list of PPCPs. Application and improvement of analytical methodologies that can detect non-volatile, polar, water-soluble pharmaceuticals in source waters at levels that could be environmentally significant (at concentrations less than parts per billion, ppb). IAG with USGS ends in FY05. APM 20 due in FY05.Subtask 2: Coordination of interagency research and public outreach activities for PPCPs. Participate on NSTC Health and Environment subcommittee wo

  3. TELEPHONIC PRESENTATION: MERCURY ...

    EPA Pesticide Factsheets

    While traditional methods for determining mercury in solid samples involve the use of aggressive chemicals to dissolve the matrix and the use of other chemicals to properly reduce the mercury to the volatile elemental form, pyrolysis-based analyzers can be used by directly weighing the solid in a sampling boat and initiating the instrumental analysis for total mercury. The research focused on in the subtasks is the development and application of state-of the-art technologies to meet the needs of the public, Office of Water, and ORD in the area of Water Quality. Located In the subtasks are the various research projects being performed in support of this Task and more in-depth coverage of each project. Briefly, each project's objective is stated below.Subtask 1: To integrate state-of-the-art technologies (polar organic chemical integrative samplers, advanced solid-phase extraction methodologies with liquid chromatography/electrospray/mass spectrometry) and apply them to studying the sources and fate of a select list of PPCPs. Application and improvement of analytical methodologies that can detect non-volatile, polar, water-soluble pharmaceuticals in source waters at levels that could be environmentally significant (at concentrations less than parts per billion, ppb). IAG with USGS ends in FY05. APM 20 due in FY05.Subtask 2: Coordination of interagency research and public outreach activities for PPCPs. Participate on NSTC Health and Environment subcommittee wo

  4. Phenotypic plasticity in a population of odonates.

    PubMed

    Bowman, Randi M; Schmidt, Sharol; Weeks, Chelsea; Clark, Hunter; Brown, Christopher; Latta, Leigh C; Edgehouse, Michael

    2018-05-31

    The maintenance of phenotypic plasticity within a species ensures survival through environmental flux. Plastic strategies are increasingly important given the number and magnitude of modern anthropogenic threats to the environment. We tested for phenotypic plasticity in the odonate Argia vivida in response to resource limitation. By limiting food availability, effectively inducing hunger, we were able to quantify shifts in agonistic behavior during intraspecific interactions. Scoring behavior in one-on-one combat trials after 1 and 4 days without food revealed phenotypic plasticity. Three classes of genotypes were identified, genotypes exhibiting either increased aggression, decreased aggression, or no phenotypic plasticity, in response to resource limitation. The variable plastic strategies in this population of odonates likely aids in maintaining fitness in fluctuating environments.

  5. Assessing the Deterrence Value of Carrier Presence Against Adversary Aggression in a Coalition Environment

    DTIC Science & Technology

    2017-09-01

    seeks to quantify the deterrence value of a CSG using a game - theoretic framework. Consider a region with several nations, where two major players stand...develop a Markov game to model the interactions between the two players and these other nations over a period of time. The game starts in Notional...establishing diplomatic advantage are equally important in deterring aggression. 14. SUBJECT TERMS carrier strike group, CSG, deterrence, Markov game

  6. Aggressive crime, alcohol and drug use, and concentrated poverty in 24 U.S. urban areas.

    PubMed

    Valdez, Avelardo; Kaplan, Charles D; Curtis, Russell L

    2007-01-01

    The nexus between substance use and aggressive crime involves a complex interrelationship among mediating individual and community-level variables. Using multilevel logistic regression models, we investigate how community-level concentration of poverty variables mediate the predictive relationships among individual level social attachment variables and substance use on aggressive crime in a large national sample of male arrestees (N = 20,602) drawn from 24 U.S. urban areas. The findings support our hypothesis that individual social attachments to marriage and the labor force (education and employment) are the principal individual-level pathway mediating the substance abuse/aggression nexus. In the random intercept model, 3.17% of the variation not explained by the individual-level predictor variables is attributable to community-level variation in urban area female-headed households and households receiving welfare. This confirms our hypothesis that social structural conditions of an urban environment differentially expose persons to conditions that predict being arrested for an aggressive crime. Our findings tend to counter the cultural theorists who argue for an indigenous culture of violence in inner-city ghettos and barrios.

  7. Understanding Driver Anger and Aggression: Attributional Theory in the Driving Environment

    ERIC Educational Resources Information Center

    Wickens, Christine M.; Wiesenthal, David L.; Flora, David B.; Flett, Gordon L.

    2011-01-01

    Two studies tested the applicability of Weiner's (1995, 1996, 2001, 2006) attributional model of social conduct to roadway environments. This model highlights the role of inferences of responsibility after making causal judgments for social transgressions. Study 1 employed written scenarios where participants were asked to imagine themselves…

  8. Aggression from Patients or Next of Kin and Exposure to Bullying Behaviors: A Conglomerate Experience?

    PubMed Central

    Notelaers, Guy; Bjorvatn, Bjørn; Moen, Bente Elisabeth; Einarsen, Ståle

    2017-01-01

    Although workplace violence and aggression have been identified as important stressors in the nursing profession, studies simultaneously comparing patient-initiated aggression and exposure to bullying behaviors at work are rather scarce. The aim of this study was to compare aggression from patients or next of kin and exposure to bullying behaviors in terms of prevalence, health-related quality of life outcomes, and potential overlap in those targeted. In the period of 2008-2009, data were collected among 2059 members of the Norwegian Nurses Organization. Latent class (LC) analysis and a multivariate analysis of variance (MANOVA) were used to investigate the proposed relationships. The results showed that aggression from patients or next of kin and exposure to bullying behaviors were perceived as separate and independent stressors. Although aggression from patients or next of kin was more frequent than workplace bullying, the latter was the only significant stressor related to health-related quality of life in terms of reduced mental health functioning. Although being a rather infrequent experience, exposure to bullying behaviors seems to have more severe health-related outcomes for nurses than aggression from patients or next of kin. Hence, the results of the study strengthen previous findings and suggest that managers must aim to maintain a positive psychosocial work environment with zero-tolerance for bullying. PMID:28270936

  9. Anti-predator behaviour changes following an aggressive encounter in the lizard Tropidurus hispidus

    PubMed Central

    Diaz-Uriarte, R

    1999-01-01

    Avoiding predators may conflict with territorial defence because a hiding territorial resident is unable to monitor its territory or defend it from conspecific intrusions. With persistent intruders, the presence of an intruder in the near past can indicate an increased probability of future intrusions. Therefore, following a conspecific-intrusion, territorial residents should minimize costs from future intrusions at the cost of higher predation risks. I conducted experiments with males of the territorial lizard Tropidurus hispidus recording approach distance (distance between predator and prey when the prey escapes) and time to re-emergence from a refuge after hiding. Past aggressive interactions affected anti-predator behaviour: lizards re-emerged sooner (compared to a control) when the predator attacked 5 min after an aggressive encounter. If the predator attacked while an aggressive encounter was ongoing, there was also a reduction in approach distance. The results are consistent with an economic hypothesis which predicts that T. hispidus incur greater predation risks to minimize future territorial intrusion; additionally they show that the effects of past and ongoing aggressive interactions are different, consistent with the minimization of present intrusion costs. These results are relevant for studies of the changes in aggressive behaviour due to changes in the social environment and for studies of the costs and (co) evolution of aggressive and anti-predator strategies. PMID:10693815

  10. Is the amount of exposure to aggressive challenging behaviour related to staff work-related well-being in intellectual disability services? Evidence from a clustered research design.

    PubMed

    Flynn, Samantha; Hastings, Richard P; Gillespie, David; McNamara, Rachel; Randell, Elizabeth

    2018-04-17

    Previous research has demonstrated an association between aggressive challenging behaviour (CB) and reductions in work-related well-being for intellectual disability (ID) support staff. Much of this research has used subjective measures of CB. To examine whether exposure to aggressive CB is associated with reduced work-related well-being in staff working in ID residential settings across the UK. A cross-sectional analysis was undertaken as part of a randomised trial; 186 staff from 100 settings completed questionnaires on their CB self-efficacy, empathy, positive work motivation, and burnout. Objective measures of aggressive CB in the preceding 16 weeks were collected from each setting. There was little association between staff exposure to aggressive CB and work-related well-being. Clustering effects were found for emotional exhaustion and positive work motivation, suggesting these variables are more likely to be influenced by the environment in which staff work. The level of clustering may be key to understanding how to support staff working in ID residential settings, and should be explored further. Longitudinal data, and studies including a comparison of staff working in ID services without aggressive CB exposure are needed to fully understand any association between aggressive CB and staff well-being. Copyright © 2018 Elsevier Ltd. All rights reserved.

  11. Pupil-class determinants of aggressive and victim behaviour in pupils.

    PubMed

    Mooij, T

    1998-09-01

    Aggressive behaviour in pupils is expressed in, e.g., bullying, sexual harassment, and violence. Different kinds of variables could be relevant in explaining a pupil's aggressive or victim behaviour. To develop a multilevel theoretical and empirical explanation for different kinds of aggressive and victim behaviour displayed by pupils in a classroom and school environment. A national survey was carried out to identify different kinds of aggressive and victim behaviour displayed by pupils and to assess other variables related to pupils, classes, and schools. A total of 1998 pupils from 100 third and fourth year classes attending 71 different secondary schools took part in the research. Data were analysed by a series of secondary multilevel analyses using the MLA-program. Being a boy, being more extravert, being more disagreeable, coming across fewer teachers with positive teaching behaviour, and attending a lower type of secondary school, help explain why someone is a perpetrator as such. Being a boy, being more disagreeable, being more emotionally unstable, being open to new ideas, and seeing more teachers as being strict, function as explanatory pupil variables for victim behaviour. Other pupil level variables determine more specific aggressive and victim behaviour aspects. Various other class level and school level variables are relevant, too. Personal and environmental pupil variables are more important than class variables but class variables are in turn more important than school variables in explaining a pupil's aggressive and victim behaviour.

  12. Chemical and biological weapons: new questions, new answers.

    PubMed Central

    Hood, E

    1999-01-01

    The words "chemical and biological weapons" (CBW) send a shiver down most spines these days. With the end of the Cold War, the possibility of a massive nuclear confrontation appears remote, so today many popular doomsday scenarios center on the aggressive use of chemical or biological warfare by rogue nations or terrorist groups. As exaggerated as some of the accounts are, with CBW cast as the latest unseen, unstoppable enemy, the threat posed by these weapons is all too real, and growing. Images p931-a PMID:10585899

  13. The Effect of Aggressive Corrosion Mediums on the Microstructure and Properties of Mild Steel

    NASA Astrophysics Data System (ADS)

    Araoyinbo, A. O.; Salleh, M. A. A. Mohd; Rahmat, A.; Azmi, A. I.; Rahim, W. M. F. Wan Abd; Achitei, D. C.; Jin, T. S.

    2018-06-01

    Mild steel is known to be one of the major construction materials and have been extensively used in most chemical and material industries due to its interesting properties which can be easily altered to suit various application areas. In this research, mild steel is exposed to different aggressive mediums in order to observe the effect of these interactions on its surface morphology and properties. The mild steel used was cut into dimensions of 7 cm length and width of 3 cm. The aggressive mediums used are 100 mls of aqueous solution of hydrochloric acid, sodium hydroxide (40 g/L), and sodium chloride (35 g/L) at room temperature. The characterizations performed are the hardness test with the Rockwell hardness tester, the surface morphology by optical microscope, surface roughness and the weight loss from the immersion test. It was observed that the hardness value and the weight loss for the different cut samples of mild steel immersed in the different aggressive mediums reduces with prolong exposure and severe pitting form of corrosion was present on its surface.

  14. Heterogeneity in the development of proactive and reactive aggression in childhood: Common and specific genetic - environmental factors

    PubMed Central

    Lacourse, Eric; Brendgen, Mara; Vitaro, Frank; Dionne, Ginette; Tremblay, Richard Ernest; Boivin, Michel

    2017-01-01

    Background Few studies are grounded in a developmental framework to study proactive and reactive aggression. Furthermore, although distinctive correlates, predictors and outcomes have been highlighted, proactive and reactive aggression are substantially correlated. To our knowledge, no empirical study has examined the communality of genetic and environmental underpinning of the development of both subtypes of aggression. The current study investigated the communality and specificity of genetic-environmental factors related to heterogeneity in proactive and reactive aggression’s development throughout childhood. Methods Participants were 223 monozygotic and 332 dizygotic pairs. Teacher reports of aggression were obtained at 6, 7, 9, 10 and 12 years of age. Joint development of both phenotypes were analyzed through a multivariate latent growth curve model. Set point, differentiation, and genetic maturation/environmental modulation hypotheses were tested using a biometric decomposition of intercepts and slopes. Results Common genetic factors accounted for 64% of the total variation of proactive and reactive aggression’s intercepts. Two other sets of uncorrelated genetic factors accounted for reactive aggression’s intercept (17%) on the one hand, and for proactive (43%) and reactive (13%) aggression’s slopes on the other. Common shared environmental factors were associated with proactive aggression’s intercept (21%) and slope (26%) and uncorrelated shared environmental factors were also associated with reactive aggression’s slope (14%). Common nonshared environmental factors explained most of the remaining variability of proactive and reactive aggression slopes. Conclusions A genetic differentiation hypothesis common to both phenotypes was supported by common genetic factors associated with the developmental heterogeneity of proactive and reactive aggression in childhood. A genetic maturation hypothesis common to both phenotypes, albeit stronger for proactive aggression, was supported by common genetic factors associated with proactive and reactive aggression slopes. A shared environment set point hypothesis for proactive aggression was supported by shared environmental factors associated with proactive aggression baseline and slope. Although there are many common features to proactive and reactive aggression, the current research underscores the advantages of differentiating them when studying aggression. PMID:29211810

  15. Attitudes of clinical staff toward the causes and management of aggression in acute old age psychiatry inpatient units.

    PubMed

    McCann, Terence V; Baird, John; Muir-Cochrane, Eimear

    2014-03-19

    In psychiatry, most of the focus on patient aggression has been in adolescent and adult inpatient settings. This behaviour is also common in elderly people with mental illness, but little research has been conducted into this problem in old age psychiatry settings. The attitudes of clinical staff toward aggression may affect the way they manage this behaviour. The purpose of this study was to examine the attitudes of clinical staff toward the causes and management of aggression in acute old age psychiatry inpatient settings. A convenience sample of clinical staff were recruited from three locked acute old age psychiatry inpatient units in Melbourne, Australia. They completed the Management of Aggression and Violence Scale, which assessed the causes and managment of aggression in psychiatric settings. Eighty-five staff completed the questionnaire, comprising registered nurses (61.1%, n = 52), enrolled nurses (27.1%, n = 23) and medical and allied health staff (11.8%, n = 10). A range of causative factors contributed to aggression. The respondents had a tendency to disagree that factors directly related to the patient contributed to this behaviour. They agreed patients were aggressive because of the environment they were in, other people contributed to them becoming aggressive, and patients from certain cultural groups were prone to these behaviours. However, there were mixed views about whether patient aggression could be prevented, and this type of behaviour took place because staff did not listen to patients. There was agreement medication was a valuable approach for the management of aggression, negotiation could be used more effectively in such challenging behaviour, and seclusion and physical restraint were sometimes used more than necessary. However, there was disagreement about whether the practice of secluding patients should be discontinued. Aggression in acute old age psychiatry inpatient units occurs occasionally and is problematic. A range of causative factors contribute to the onset of this behaviour. Attitudes toward the management of aggression are complex and somewhat contradictory and can affect the way staff manage this behaviour; therefore, wide-ranging initiatives are needed to prevent and deal with this type of challenging behaviour.

  16. Attitudes of clinical staff toward the causes and management of aggression in acute old age psychiatry inpatient units

    PubMed Central

    2014-01-01

    Background In psychiatry, most of the focus on patient aggression has been in adolescent and adult inpatient settings. This behaviour is also common in elderly people with mental illness, but little research has been conducted into this problem in old age psychiatry settings. The attitudes of clinical staff toward aggression may affect the way they manage this behaviour. The purpose of this study was to examine the attitudes of clinical staff toward the causes and management of aggression in acute old age psychiatry inpatient settings. Methods A convenience sample of clinical staff were recruited from three locked acute old age psychiatry inpatient units in Melbourne, Australia. They completed the Management of Aggression and Violence Scale, which assessed the causes and managment of aggression in psychiatric settings. Results Eighty-five staff completed the questionnaire, comprising registered nurses (61.1%, n = 52), enrolled nurses (27.1%, n = 23) and medical and allied health staff (11.8%, n = 10). A range of causative factors contributed to aggression. The respondents had a tendency to disagree that factors directly related to the patient contributed to this behaviour. They agreed patients were aggressive because of the environment they were in, other people contributed to them becoming aggressive, and patients from certain cultural groups were prone to these behaviours. However, there were mixed views about whether patient aggression could be prevented, and this type of behaviour took place because staff did not listen to patients. There was agreement medication was a valuable approach for the management of aggression, negotiation could be used more effectively in such challenging behaviour, and seclusion and physical restraint were sometimes used more than necessary. However, there was disagreement about whether the practice of secluding patients should be discontinued. Conclusions Aggression in acute old age psychiatry inpatient units occurs occasionally and is problematic. A range of causative factors contribute to the onset of this behaviour. Attitudes toward the management of aggression are complex and somewhat contradictory and can affect the way staff manage this behaviour; therefore, wide-ranging initiatives are needed to prevent and deal with this type of challenging behaviour. PMID:24642026

  17. Hypothalamic attack: a wonderful artifact or a useful perspective on escalation and pathology in aggression? A viewpoint.

    PubMed

    Kruk, Menno R

    2014-01-01

    W.R. Hess' early demonstration of aggressive responses evoked by electrical stimulation in the cat's hypothalamus had a significant impact on the development of psychological and behavioral concepts. Many ideas on behavioral routines, allegedly organized in the brainstem, derive from his observation. Similar responses have since been evoked from the hypothalamus of many different species, suggesting that the mechanism mediating these responses is evolutionarily well preserved. However, these effects have also been portrayed as artificial responses to an artificial stimulus in an artificial environment. True enough; after many years of research, crucial questions on the underlying mechanism remain unanswered. Questions such as: How do they emerge in the first place? What neuronal elements mediate these responses? What is their role in "spontaneous" aggression? In the first part of this chapter we show methodology to study such questions in a consistent way using behavioral, physiological, anatomical, and pharmacological findings on hypothalamic attack in rats. In the second part we suggest that one important function of the underlying mechanism is to match the dynamics of the endocrine stress response with the dynamics of the behavioral and physiological requirements of coping with conflicts. This neuroendocrine-behavioral matching seems crucial right from the first emergence of the aggressive response in inexperienced animals, up to the full-blown violent responding in fully experienced animals. Impeding these essential functions results in inadequate coping with conflicts. The stress response during a first conflict in an inexperienced individual in an unfamiliar environment seems to rapidly initialize a crucial change in a mechanism involved in the appraisal of social signals during conflict. That change has enduring consequences for future conflict strategies. This concept opens another perspective on "escalated" or "pathological" aggression, especially so in individuals with a dysfunctional stress response.

  18. Social context affects behavior, preoptic area gene expression, and response to D2 receptor manipulation during territorial defense in a cichlid fish.

    PubMed

    Weitekamp, C A; Nguyen, J; Hofmann, H A

    2017-07-01

    Social context often has profound effects on behavior, yet the neural and molecular mechanisms which mediate flexible behavioral responses to different social environments are not well understood. We used the African cichlid fish, Astatotilapia burtoni, to examine aggressive defense behavior across three social contexts representing different motivational states: a reproductive opportunity, a familiar male and a neutral context. To elucidate how differences in behavior across contexts may be mediated by neural gene expression, we examined gene expression in the preoptic area, a brain region known to control male aggressive and sexual behavior. We show that social context has broad effects on preoptic gene expression. Specifically, we found that the expression of genes encoding nonapeptides and sex steroid receptors are upregulated in the familiar male context. Furthermore, circulating levels of testosterone and cortisol varied markedly depending on social context. We also manipulated the D2 receptor (D2R) in each social context, given that it has been implicated in mediating context-dependent behavior. We found that a D2R agonist reduced intruder-directed aggression in the reproductive opportunity and familiar male contexts, while a D2R antagonist inhibited intruder-directed aggression in the reproductive opportunity context and increased aggression in the neutral context. Our results demonstrate a critical role for preoptic gene expression, as well as circulating steroid hormone levels, in encoding information from the social environment and in shaping adaptive behavior. In addition, they provide further evidence for a role of D2R in context-dependent behavior. © 2017 John Wiley & Sons Ltd and International Behavioural and Neural Genetics Society.

  19. Dead certain: confidence and conservatism predict aggression in simulated international crisis decision-making.

    PubMed

    Johnson, Dominic D P; McDermott, Rose; Cowden, Jon; Tingley, Dustin

    2012-03-01

    Evolutionary psychologists have suggested that confidence and conservatism promoted aggression in our ancestral past, and that this may have been an adaptive strategy given the prevailing costs and benefits of conflict. However, in modern environments, where the costs and benefits of conflict can be very different owing to the involvement of mass armies, sophisticated technology, and remote leadership, evolved tendencies toward high levels of confidence and conservatism may continue to be a contributory cause of aggression despite leading to greater costs and fewer benefits. The purpose of this paper is to test whether confidence and conservatism are indeed associated with greater levels of aggression-in an explicitly political domain. We present the results of an experiment examining people's levels of aggression in response to hypothetical international crises (a hostage crisis, a counter-insurgency campaign, and a coup). Levels of aggression (which range from concession to negotiation to military attack) were significantly predicted by subjects' (1) confidence that their chosen policy would succeed, (2) score on a liberal-conservative scale, (3) political party affiliation, and (4) preference for the use of military force in real-world U.S. policy toward Iraq and Iran. We discuss the possible adaptive and maladaptive implications of confidence and conservatism for the prospects of war and peace in the modern world.

  20. Growing up in armed groups: trauma and aggression among child soldiers in DR Congo

    PubMed Central

    Hermenau, Katharin; Hecker, Tobias; Maedl, Anna; Schauer, Maggie; Elbert, Thomas

    2013-01-01

    Background Child soldiers are often both victims and perpetrators of horrendous acts of violence. Research with former child soldiers has consistently shown that exposure to violence is linked to trauma-related disorders and that living in a violent environment is correlated with enhanced levels of aggression. Objective To gain more insight into the experiences and the mental health status of former child soldiers, we conducted a survey with N=200 former child soldiers and adult combatants in the DR Congo. Methods We conducted semi-structured interviews concerning military experiences, experienced and perpetrated violence, and mental health. Results Former child soldiers reported more experienced and perpetrated violence, a greater severity of trauma-related suffering, as well as higher appetitive aggression than adult ex-combatants. Appetitive aggression was related to more perpetrated violence, higher military ranks, voluntary recruitment and higher rates of reenlistments in former child soldiers. Conclusions Our results indicate that growing up in an armed group is related to higher levels of trauma-related disorders and aggressive behavior. This may explain the challenge of reintegrating former child soldiers. It is thus important to consider mental health problems, particularly trauma-related disorders and aggressive behavior, of former child soldiers for designing adequate reintegration programs. PMID:24224078

  1. Advances in concrete materials for sewer systems affected by microbial induced concrete corrosion: A review.

    PubMed

    Grengg, Cyrill; Mittermayr, Florian; Ukrainczyk, Neven; Koraimann, Günther; Kienesberger, Sabine; Dietzel, Martin

    2018-05-01

    Microbial induced concrete corrosion (MICC) is recognized as one of the main degradation mechanisms of subsurface infrastructure worldwide, raising the demand for sustainable construction materials in corrosive environments. This review aims to summarize the key research progress acquired during the last decade regarding the understanding of MICC reaction mechanisms and the development of durable materials from an interdisciplinary perspective. Special focus was laid on aspects governing concrete - micoorganisms interaction since being the central process steering biogenic acid corrosion. The insufficient knowledge regarding the latter is proposed as a central reason for insufficient progress in tailored material development for aggressive wastewater systems. To date no cement-based material exists, suitable to withstand the aggressive conditions related to MICC over its entire service life. Research is in particular needed on the impact of physiochemical material parameters on microbial community structure, growth characteristics and limitations within individual concrete speciation. Herein an interdisciplinary approach is presented by combining results from material sciences, microbiology, mineralogy and hydrochemistry to stimulate the development of novel and sustainable materials and mitigation strategies for MICC. For instance, the application of antibacteriostatic agents is introduced as an effective instrument to limit microbial growth on concrete surfaces in aggressive sewer environments. Additionally, geopolymer concretes are introduced as highly resistent in acid environments, thus representing a possible green alternative to conventional cement-based construction materials. Copyright © 2018 Elsevier Ltd. All rights reserved.

  2. Aggression directed towards members of the oral and maxillofacial surgical team.

    PubMed

    Mannion, C J; Gordon, C

    2018-06-06

    Oral and maxillofacial surgery (OMFS) is an acute surgical specialty, and members of the surgical team may be exposed to challenging incidents. We have evaluated the experiences of members of OMFS teams and their experiences of aggressive and abusive behaviour. Education and training in the resolution of such conflicts should be offered to all members of the team to allow a safe and secure working environment. Copyright © 2018 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

  3. SOLVENT NANOFILTRATION USING LOW-COST INORGANIC MEMBRANE MODULES - PHASE I

    EPA Science Inventory

    This Phase I project addresses: (1) development of fully inorganic nanofiltration (NF) membrane modules that have the attributes of low-cost, excellent chemical resistance in aggressive organic and aqueous media and high thermal stability; and (2) demonstration of the perfo...

  4. Verbal and Physical Abuse toward Mothers: The Role of Family Configuration, Environment, and Coping Strategies.

    ERIC Educational Resources Information Center

    Pagani, Linda; Larocque, Denis; Vitaro, Frank; Tremblay, Richard E.

    2003-01-01

    Studied factors that can increase the risk of abusive behaviors toward mothers. Findings for 6,397 French-speaking Canadian adolescents show that parental divorce is associated with a greater risk of physical aggression directed toward mothers, but family environment and parental coping strategies partially mediated that relationship. (SLD)

  5. The Family Environment and Developmental Psychopathology: The Unique and Interactive Effects of Depression, Attention, and Conduct Problems

    ERIC Educational Resources Information Center

    George, Carrie; Herman, Keith C.; Ostrander, Rick

    2006-01-01

    Prior studies have found remarkable similarity in the family characteristics across a wide range of child psychopathologies. This study investigated the unique relationships between symptoms of depression, conduct problems/aggression, and inattention/hyperactivity and characteristics of the family environment. Parents and teachers completed…

  6. Comparison of Family Environments of Abused versus Non-Abused Children.

    ERIC Educational Resources Information Center

    Davis, Cynthia A.; Graybill, Daniel

    1983-01-01

    Compared Moos Family Environment Scale scores from 15 physically abusive families with scores from 15 nonabusive families. Results showed that abusive families were less supportive of one another and less free to express their wants and desires, more independent, more likely to express anger and aggression, and more rigid. (JAC)

  7. Protection of Conductive and Non-conductive Advanced Polymer-based Paints from Highly Aggressive Oxidative Environments

    NASA Technical Reports Server (NTRS)

    Gudimenko, Y.; Ng, R.; Iskanderova, Z.; Kleiman, J.; Grigorevsky, A.; Kiseleva, L.; Finckenor, M.; Edwards, D.

    2005-01-01

    Research has been continued to further improve the space durability of conductive and non-conductive polymer-based paints and of conductive thermal control paints for space applications. Efforts have been made to enhance the space durability and stability of functional Characteristics in ground-based space environment imitating conditions, using specially developed surface modification treatment. The results of surface modification of new conductive paints, including the ground-based testing in aggressive oxidative environments, such as atomic oxygen/UV and oxygen plasma, and performance evaluation are presented. Functional properties and performance characteristics, such as thermal optical properties (differential solar absorptance and thermal emittance representing the thermal optical performance of thermal control paints) and surface resistivity characteristics of pristine, surface modified, and tested materials were verified. Extensive surface analysis studies have been performed using complementary surface analyses including SEM/EDS and XPS. Test results revealed that the successfully treated materials exhibit reduced mass loss and no surface morphology change, thus indicating good protection from the severe oxidative environment. It was demonstrated that the developed surface modification treatment could be applied successfully to charge dissipative and conductive paints.

  8. Behavioral and Pharmacogenetics of Aggressive Behavior

    PubMed Central

    Takahashi, Aki; Quadros, Isabel M.; de Almeida, Rosa M. M.; Miczek, Klaus A.

    2013-01-01

    Serotonin (5-HT) has long been considered as a key transmitter in the neurocircuitry controlling aggression. Impaired regulation of each subtype of 5-HT receptor, 5-HT transporter, synthetic and metabolic enzymes has been linked particularly to impulsive aggression. The current summary focuses mostly on recent findings from pharmacological and genetic studies. The pharmacological treatments and genetic manipulations or polymorphisms of a specific target (e.g., 5-HT1A receptor) can often result in inconsistent results on aggression, due to “phasic” effects of pharmacological agents vs “trait”-like effects of genetic manipulations. Also, the local administration of a drug using the intracranial microinjection technique has shown that activation of specific subtypes of 5-HT receptors (5-HT1A and 5-HT1B) in mesocorticolimbic areas can reduce species-typical and other aggressive behaviors, but the same receptors in the medial prefrontal cortex or septal area promote escalated forms of aggression. Thus, there are receptor populations in specific brain regions that preferentially modulate specific types of aggression. Genetic studies have shown important gene × environment interactions; it is likely that the polymorphisms in the genes of 5-HT transporters (e.g., MAO A) or rate-limiting synthetic and metabolic enzymes of 5-HT determine the vulnerability to adverse environmental factors that escalate aggression. We also discuss the interaction between the 5-HT system and other systems. Modulation of 5-HT neurons in the dorsal raphe nucleus by GABA, glutamate, and CRF profoundly regulate aggressive behaviors. Also, interactions of the 5-HT system with other neuropeptides (arginine vasopressin, oxytocin, neuropeptide Y, opioid) have emerged as important neurobiological determinants of aggression. Studies of aggression in genetically modified mice identified several molecules that affect the 5-HT system directly (e.g., Tph2, 5-HT1B, 5-HT transporter, Pet1, MAOA) or indirectly (e.g. BDNF, nNOS, αCaMKII, Neuropeptide Y). The future agenda delineates specific receptor subpopulations for GABA, glutamate and neuropeptides as they modulate the canonical aminergic neurotransmitters in brainstem, limbic and cortical regions with the ultimate outcome of attenuating or escalating aggressive behavior. PMID:22297576

  9. Intruder colour and light environment jointly determine how nesting male stickleback respond to simulated territorial intrusions.

    PubMed

    Bolnick, Daniel I; Hendrix, Kimberly; Jordan, Lyndon Alexander; Veen, Thor; Brock, Chad D

    2016-08-01

    Variation in male nuptial colour signals might be maintained by negative frequency-dependent selection. This can occur if males are more aggressive towards rivals with locally common colour phenotypes. To test this hypothesis, we introduced red or melanic three-dimensional printed-model males into the territories of nesting male stickleback from two optically distinct lakes with different coloured residents. Red-throated models were attacked more in the population with red males, while melanic models were attacked more in the melanic male lake. Aggression against red versus melanic models also varied across a depth gradient within each lake, implying that the local light environment also modulated the strength of negative frequency dependence acting on male nuptial colour. © 2016 The Author(s).

  10. Sex differences in aggression among children of low and high gender inequality backgrounds: a comparison of gender role and sexual selection theories.

    PubMed

    Nivette, Amy E; Eisner, Manuel; Malti, Tina; Ribeaud, Denis

    2014-01-01

    It is well understood in aggression research that males tend to exhibit higher levels of physical aggression than females. Yet there are still a number of gaps in our understanding of variation in sex differences in children's aggression, particularly in contexts outside North America. A key assumption of social role theory is that sex differences vary according to gender polarization, whereas sexual selection theory accords variation to the ecological environment that consequently affects male competition [Archer, J. (2009). Behavioral and Brain Sciences, 32, 249-311; Kenrick, D., & Griskevicious, V. (2009). More holes in social roles [Comment]. Behavioral and Brain Sciences, 32, 283-285]. In the present paper, we explore these contradicting theoretical frameworks by examining data from a longitudinal study of a culturally diverse sample of 863 children at ages 7-13 in Zurich, Switzerland. Making use of the large proportion of children from highly diverse immigrant background we compare the size of the sex difference in aggression between children whose parents were born in countries with low and with high levels of gender inequality. The results show that sex differences in aggression are generally larger among children with parents from high gender inequality backgrounds. However, this effect is small in comparison to the direct effect of a child's biological sex. We discuss implications for future research on sex differences in children's aggression. © 2014 Wiley Periodicals, Inc.

  11. Alcohol Mixed with Energy Drink Use as an Event-Level Predictor of Physical and Verbal Aggression in Bar Conflicts.

    PubMed

    Miller, Kathleen E; Quigley, Brian M; Eliseo-Arras, Rebecca K; Ball, Natalie J

    2016-01-01

    Young adult use of alcohol mixed with caffeinated energy drinks (AmEDs) has been globally linked with increased odds of interpersonal aggression, compared with the use of alcohol alone. However, no prior research has linked these behaviors at the event level in bar drinking situations. The present study assessed whether AmED use is associated with the perpetration of verbal and physical aggression in bar conflicts at the event level. In Fall 2014, a community sample of 175 young adult AmED users (55% female) completed a web survey describing a recent conflict experienced while drinking in a bar. Use of both AmED and non-AmED alcoholic drinks in the incident were assessed, allowing calculation of our main predictor variable, the proportion of AmEDs consumed (AmED/total drinks consumed). To measure perpetration of aggression, participants reported on the occurrence of 6 verbal and 6 physical acts during the bar conflict incident. Linear regression analyses showed that the proportion of AmEDs consumed predicted scores for perpetration of both verbal aggression (β = 0.16, p < 0.05) and physical aggression (β = 0.19, p < 0.01) after controlling for gender, age, sensation-seeking and aggressive personality traits, aggressive alcohol expectancies, aggressogenic physical and social bar environments, and total number of drinks. Results of this study suggest that in alcohol-related bar conflicts, higher levels of young adult AmED use are associated with higher levels of aggression perpetration than alcohol use alone and that the elevated risk is not attributable to individual differences between AmED users and nonusers or to contextual differences in bar drinking settings. While future research is needed to identify motivations, dosages, and sequencing issues associated with AmED use, these beverages should be considered a potential risk factor in the escalation of aggressive bar conflicts. Copyright © 2016 by the Research Society on Alcoholism.

  12. Online Mate-Retention Tactics on Facebook Are Associated With Relationship Aggression.

    PubMed

    Brem, Meagan J; Spiller, Laura C; Vandehey, Michael A

    2015-10-01

    A measure of Facebook-related mate-retention tactics was developed to investigate the relationship between online behaviors and intimate partner aggression. One hundred and seventy-seven young adults (65 men, 112 women) completed questionnaires that included measures of online and offline mate-retention tactics, Facebook jealousy, Facebook surveillance, and intimate partner violence. A factor analysis yielded four subscales for the Facebook Mate-Retention Tactic Inventory (FMRTI): Care and Affection, Jealousy and Surveillance, Possession Signals, and Punishment of Infidelity Threat. The FMRTI total scores were positively correlated with Facebook jealousy, Facebook surveillance, and use of offline mate-retention tactics. The Jealousy and Surveillance subscale uniquely predicted intimate partner psychological and physical aggression over and above existing measures. Facebook mate-retention tactics fully mediated the relation between Facebook jealousy and both intimate partner psychological and physical aggression. The current study provides preliminary evidence for conceptualizing Facebook as an environment for the use of mate-retention tactics that have real-life implications for intimate partner violence. © The Author(s) 2014.

  13. [Family violence and aggressive and oppositional behavior in childhood: a literature review].

    PubMed

    Pesce, Renata

    2009-01-01

    This article presents a review of the world literature about two important subjects: family violence and problems of aggressive behavior and oppositional defiant disorder in childhood. We opted for publications that had used the CBCL- Child Behavior Checklist for investigating behavior problems in children. This instrument is internationally recognized for its reliability and validity, considered an efficient tool for identifying behavior problems in children. Our findings showed that marital violence predominated in the studies as kind of familiar violence able to cause problems of aggressiveness and transgression in children. Another point discussed was the lack of consensus on the terms used in the articles to refer to such behavior problems. The review showed the need for in-depth studies into this subject, mainly in the sense of thinking about prevention and health promotion in childhood and adolescence. Aggressive behavior in children tends to remain and increase over time, a fact that points to the need for strategies for preventing these problems in the school, familiar and health environments.

  14. The evolution of humor from male aggression.

    PubMed

    Shuster, Sam

    2012-01-01

    The response to seeing a man riding a unicycle was reported to be consistently related to the viewer's sex and stage of physical development. To see if this observation was universal, observations of responses were collected from 23 male and 9 female unicyclists aged 15-69 years, with 2-40 years cycling experience across four continents. With two exceptions among men, the findings were the same as those originally reported: children showed interest and curiosity, young girls showed little interest, while adult women showed a kindly, concerned, praising response. By contrast, boys showed physical aggression, which became more verbal, merging in the later teens to the snide, aggressive, stereotyped humorous response shown by adult males, which became less frequent in elderly men. The universality of the response across different individuals, environments, and dates of observation suggests an endogenous mechanism, and the association with masculine development relates this to androgen. The theoretical consequences are discussed. It is concluded that humor develops from aggression in males and is evolutionarily related to sexual selection.

  15. Peripheral anosmia attenuates female-enhanced aggression in male rats.

    PubMed

    Bergvall, A H; Vega Matuszczyk, J; Dahlöf, L G; Hansen, S

    1991-07-01

    It is well established that male rats with prior access to sexually active females show enhanced offensive aggression toward unfamiliar male intruders. The present study assessed the importance of the sense of smell for this facilitatory effect. It was found in 2 independent experiments that anosmia, induced peripherally by surgically removing the olfactory epithelium and cutting the olfactory nerves, reduced baseline levels of offensive aggression and significantly attenuated the female-enhanced aggression effect. It was also found that sexual performance of anosmic rats was context-dependent, in that it was more impaired in the homecage environment than in standard observation cages. In contrast to sham-operated males, the experimental animals showed no preference for estrous over anestrous females in a mate choice test. Anosmic males did not appear more fearful than controls, as assessed in a hyponeophagia test, but they showed less exploratory behavior (rearing and head-dipping) in the hole-board test, and less rearing activity in automated activity boxes.

  16. LABORATORY MICROCOSM EXPERIMENTS OF OXIDATION PROCESSES AFTER STEAM INJECTION

    EPA Science Inventory

    Aggressive thermal methods such as steam injection or resistive heating are known to be effective for the recovery of many types of volatile and semivolatile compounds. It has been suggested that oxidation or other chemical reactions that occur at remediation temperatures can ai...

  17. A parametric study of surface roughness and bonding mechanisms of aluminum alloys with epoxies: a molecular dynamics simulation

    NASA Astrophysics Data System (ADS)

    Timilsina, Rajendra; Termaath, Stephanie

    The marine environment is highly aggressive towards most materials. However, aluminium-magnesium alloys (Al-Mg, specifically, 5xxx series) have exceptionally long service life in such aggressive marine environments. For instance, an Al-Mg alloy, AA5083, is extensively used in naval structures because of its good mechanical strength, formability, seawater corrosion resistance and weldability. However, bonding mechanisms of these alloys with epoxies in a rough surface environment are not fully understood yet. It requires a rigorous investigation at molecular or atomic levels. We performed a molecular dynamics simulation to study an adherend surface preparation and surface bonding mechanisms of Al-Mg alloy (AA5083) with different epoxies by developing several computer models. Various distributions of surface roughness are introduced in the models and performed molecular dynamics simulations. Formation of a beta phase (Al3Mg2) , microstructures, bonding energies at the interface, bonding strengths and durability are investigated. Office of Naval Research.

  18. Volcano-related materials in concretes: a comprehensive review.

    PubMed

    Cai, Gaochuang; Noguchi, Takafumi; Degée, Hervé; Zhao, Jun; Kitagaki, Ryoma

    2016-04-01

    Massive volcano-related materials (VRMs) erupted from volcanoes bring the impacts to natural environment and humanity health worldwide, which include generally volcanic ash (VA), volcanic pumice (VP), volcanic tuff (VT), etc. Considering the pozzolanic activities and mechanical characters of these materials, civil engineers propose to use them in low carbon/cement and environment-friendly concrete industries as supplementary cementitious materials (SCMs) or artificial/natural aggregates. The utilization of VRMs in concretes has attracted increasing and pressing attentions from research community. Through a literature review, this paper presents comprehensively the properties of VRMs and VRM concretes (VRMCs), including the physical and chemical properties of raw VRMs and VRMCs, and the fresh, microstructural and mechanical properties of VRMCs. Besides, considering environmental impacts and the development of long-term properties, the durability and stability properties of VRMCs also are summarized in this paper. The former focuses on the resistance properties of VRMCs when subjected to aggressive environmental impacts such as chloride, sulfate, seawater, and freezing-thawing. The latter mainly includes the fatigue, creep, heat-insulating, and expansion properties of VRMCs. This study will be helpful to promote the sustainability in concrete industries, protect natural environment, and reduce the impacts of volcano disaster. Based on this review, some main conclusions are discussed and important recommendations regarding future research on the application of VRMs in concrete industries are provided.

  19. Proximity alert! Distance related cuneus activation in military veterans with anger and aggression problems.

    PubMed

    Heesink, Lieke; Edward Gladwin, Thomas; Terburg, David; van Honk, Jack; Kleber, Rolf; Geuze, Elbert

    2017-08-30

    Problems involving anger and aggression are common after military deployment, and may involve abnormal responses to threat. This study therefore investigated effects on neural activation related to threat and escapability among veterans with deployment experience. Twenty-seven male veterans with anger and aggression problems (Anger group) and 30 Control veterans performed a virtual predator-task during fMRI measurement. In this task, threat and proximity were manipulated. The distance of cues determined their possibility for escape. Cues signaled impending attack by zooming in towards the participant. If Threat cues, but not Safe cues, reached the participants without being halted by a button press, an aversive noise (105dB scream) was presented. In both the Threat and the Safe condition, closer proximity of the virtual predator resulted in stronger activation in the cuneus in the Anger versus Control group. The results suggest that anger and aggression problems are related to a generalized sensitivity to proximity rather than preparatory processes related to task-contingent aversive stimuli. Anger and aggression problems in natural, dynamically changing environments may be related to an overall heightened vigilance, which is non-adaptively driven by proximity. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.

  20. Social media, cyber-aggression and student mental health on a university campus.

    PubMed

    Mishna, Faye; Regehr, Cheryl; Lacombe-Duncan, Ashley; Daciuk, Joanne; Fearing, Gwendolyn; Van Wert, Melissa

    2018-06-01

    Information and communication technologies (ICTs) offer immense benefits for university students including enhancing engagement and connections with others and promoting self-directed and interactive learning. Perceived anonymity and the absence of social cues, however, may contribute to risk of interpersonal aggression. While extensive research examines bullying in child and adolescent educational settings, this study addresses a gap regarding post-secondary environments. An internet-based survey was provided to 5004 university students to examine the nature, extent and consequences of cyber-aggression. The survey received a response from 1350 students, a response rate of 28.5%. To enable further exploration, nine focus groups and eight individual interviews were conducted. This exploratory study found one quarter of respondents had a private video or photo shared without their permission and 28% were sent angry, vulgar, threatening or intimating messages. Perpetrators were most likely to be a friend (50%), another student (20%) or an intimate partner (18%). Focus group data revealed risks of ICTs and the need for resources and support to address students' wellbeing in the context of cyber-aggression. Cyber-aggression is experienced by a significant minority of university students, impacting their sense of wellbeing and mental health.

  1. Harsh Parenting in Relation to Child Emotion Regulation and Aggression

    PubMed Central

    Chang, Lei; Schwartz, David; Dodge, Kenneth A.; McBride-Chang, Catherine

    2009-01-01

    This study presents a model of harsh parenting that has an indirect effect, as well as a direct effect, on child aggression in the school environment through the mediating process of child emotion regulation. Tested on a sample of 325 Chinese children and their parents, the model showed adequate goodness of fit. Also investigated were interaction effects between parents’ and children’s gender. Mothers’ harsh parenting affected child emotion regulation more strongly than fathers’, whereas harsh parenting emanating from fathers had a stronger effect on child aggression. Fathers’ harsh parenting also affected sons more than daughters, whereas there was no gender differential effect with mothers’ harsh parenting. These results are discussed with an emphasis on negative emotionality as a potentially common cause of family perturbations, including parenting and child adjustment problems. PMID:14640808

  2. Understanding Relations among Early Family Environment, Cortisol Response, and Child Aggression via a Prevention Experiment

    ERIC Educational Resources Information Center

    O'Neal, Colleen R.; Brotman, Laurie Miller; Huang, Keng-Yen; Gouley, Kathleen Kiely; Kamboukos, Dimitra; Calzada, Esther J.; Pine, Daniel S.

    2010-01-01

    This study examined relations among family environment, cortisol response, and behavior in the context of a randomized controlled trial with 92 children (M = 48 months) at risk for antisocial behavior. Previously, researchers reported an intervention effect on cortisol response in anticipation of a social challenge. The current study examined…

  3. Association of Childhood Chronic Physical Aggression with a DNA Methylation Signature in Adult Human T Cells

    PubMed Central

    Guillemin, Claire; Vitaro, Frank; Côté, Sylvana M.; Hallett, Michael; Tremblay, Richard E.; Szyf, Moshe

    2014-01-01

    Background Chronic physical aggression (CPA) is characterized by frequent use of physical aggression from early childhood to adolescence. Observed in approximately 5% of males, CPA is associated with early childhood adverse environments and long-term negative consequences. Alterations in DNA methylation, a covalent modification of DNA that regulates genome function, have been associated with early childhood adversity. Aims To test the hypothesis that a trajectory of chronic physical aggression during childhood is associated with a distinct DNA methylation profile during adulthood. Methods We analyzed genome-wide promoter DNA methylation profiles of T cells from two groups of adult males assessed annually for frequency of physical aggression between 6 and 15 years of age: a group with CPA and a control group. Methylation profiles covering the promoter regions of 20 000 genes and 400 microRNAs were generated using MeDIP followed by hybridization to microarrays. Results In total, 448 distinct gene promoters were differentially methylated in CPA. Functionally, many of these genes have previously been shown to play a role in aggression and were enriched in biological pathways affected by behavior. Their locations in the genome tended to form clusters spanning millions of bases in the genome. Conclusions This study provides evidence of clustered and genome-wide variation in promoter DNA methylation in young adults that associates with a history of chronic physical aggression from 6 to 15 years of age. However, longitudinal studies of methylation during early childhood will be necessary to determine if and how this methylation variation in T cells DNA plays a role in early development of chronic physical aggression. PMID:24691403

  4. Aggression behaviour induced by oral administration of the Janus-kinase inhibitor tofacitinib, but not oclacitinib, under stressful conditions.

    PubMed

    Fukuyama, Tomoki; Tschernig, Thomas; Qi, Yulin; Volmer, Dietrich A; Bäumer, Wolfgang

    2015-10-05

    Janus kinase (JAK) inhibitors have recently been developed for allergic diseases. We focused on the 2 different JAK inhibitors, tofacitinib (selective for JAK3) and oclacitinib (selective for JAK1 and 2), to clarify the mechanism of anti-inflammatory and anti-itching potency of these drugs. In the process of detecting anti-itching potency, we observed that tofacitinib treated mice showed aggression behaviour. The objective of the study reported here was to investigate the aggressive behaviour induced by tofacitinib by using a mouse model of allergic dermatitis and the resident-intruder test. For the allergic dermatitis model, female BALB/c mice were sensitised and challenged topically with toluene-2,4-diisocyanate (TDI). Vehicle, tofacitinib or oclacitinib, was administered orally 30 min before TDI challenge. Scratching, aggression and standing behaviours were monitored in the 60 min period immediately following challenge of TDI. Another group of male BALB/c mice treated with vehicle, tofacitinib or oclacitinib was evaluated in the resident-intruder test and brains were obtained to determine blood brain barrier penetration. In the allergic dermatitis model, a significant increase in aggression and standing behaviour was only obvious in the tofacitinib treatment group. There was no effect in non-sensitised mice, but similar aggression was also induced by tofacitinib in male resident-intruder test. Penetration of blood-brain barrier was observed both in tofacitinib and oclacitinib treated mice. These results suggest that aggression was induced by tofacitinib under some kind of stressful environment. This study indicates a possible role of the JAK-STAT pathway in modulation of aggression behaviour. Copyright © 2015 Elsevier B.V. All rights reserved.

  5. The Effect of Neighborhood Context on the Relationship Between Substance Misuse and Weapons Aggression in Urban Adolescents Seeking ED Care

    PubMed Central

    Goldstick, Jason Elliott; Lipton, Robert I.; Carter, Patrick; Stoddard, Sarah A.; Newton, Manya F.; Reischl, Thomas; Walton, Maureen; Zimmerman, Marc A.; Cunningham, Rebecca M.

    2015-01-01

    Background Frameworks for studying the ecology of human behavior suggest that multiple levels of the environment influence behavior and that these levels interact. Applied to studies of weapons aggression, this suggests proximal risk factor (e.g., substance use) effects may differ across neighborhoods. Objectives To estimate how the association between weapons aggression and substance use varies as a function of several community-level variables. Methods Individual-level measures (demographics, behavioral measures) were obtained from a survey of youth aged 14–24 years old seeking care at a Level-1 ED in Flint, Michigan. Community-level variables were obtained from public sources. Logistic generalized additive models were used to test whether community-level variables (crime rates, alcohol outlets, demographics) modify the link between individual-level substance use variables and the primary outcome measure: self-reported past 6-month weapon (firearm/knife) related aggression. Results The effect of marijuana misuse on weapons aggression varied significantly as a function of five community-level variables: racial composition, vacant housing rates, female headed household rates, density of package alcohol outlets, and nearby drug crime rates. The effect of high-risk alcohol use did not depend on any of the eight community variables tested. Conclusions The relationship between marijuana misuse and weapons aggression differed across neighborhoods with generally less association in more disadvantaged neighborhoods, while high-risk alcohol use showed a consistently high association with weapons aggression that did not vary across neighborhoods. The results aid in understanding the contributions of alcohol and marijuana use to the etiology of weapon-related aggression among urban youth, but further study in the general population is required. PMID:25607807

  6. The Effect of Neighborhood Context on the Relationship Between Substance Misuse and Weapons Aggression in Urban Adolescents Seeking ED Care.

    PubMed

    Goldstick, Jason Elliott; Lipton, Robert I; Carter, Patrick; Stoddard, Sarah A; Newton, Manya F; Reischl, Thomas; Walton, Maureen; Zimmerman, Marc A; Cunningham, Rebecca M

    2015-04-01

    Frameworks for studying the ecology of human behavior suggest that multiple levels of the environment influence behavior and that these levels interact. Applied to studies of weapons aggression, this suggests proximal risk factor (e.g., substance use) effects may differ across neighborhoods. To estimate how the association between weapons aggression and substance use varies as a function of several community-level variables. Individual-level measures (demographics, behavioral measures) were obtained from a survey of youth aged 14-24 years old seeking care at a Level-1 ED in Flint, Michigan. Community-level variables were obtained from public sources. Logistic generalized additive models were used to test whether community-level variables (crime rates, alcohol outlets, demographics) modify the link between individual-level substance use variables and the primary outcome measure: self-reported past 6-month weapon (firearm/knife) related aggression. The effect of marijuana misuse on weapons aggression varied significantly as a function of five community-level variables: racial composition, vacant housing rates, female headed household rates, density of package alcohol outlets, and nearby drug crime rates. The effect of high-risk alcohol use did not depend on any of the eight community variables tested. The relationship between marijuana misuse and weapons aggression differed across neighborhoods with generally less association in more disadvantaged neighborhoods, while high-risk alcohol use showed a consistently high association with weapons aggression that did not vary across neighborhoods. The results aid in understanding the contributions of alcohol and marijuana use to the etiology of weapon-related aggression among urban youth, but further study in the general population is required.

  7. Staying alive: evolution, culture, and women's intrasexual aggression.

    PubMed

    Campbell, A

    1999-04-01

    Females' tendency to place a high value on protecting their own lives enhanced their reproductive success in the environment of evolutionary adaptation because infant survival depended more upon maternal than on paternal care and defence. The evolved mechanism by which the costs of aggression (and other forms of risk taking) are weighted more heavily for females may be a lower threshold for fear in situations which pose a direct threat of bodily injury. Females' concern with personal survival also has implications for sex differences in dominance hierarchies because the risks associated with hierarchy formation in nonbonded exogamous females are not offset by increased reproductive success. Hence among females, disputes do not carry implications for status with them as they do among males, but are chiefly connected with the acquisition and defence of scarce resources. Consequently, female competition is more likely to take the form of indirect aggression or low-level direct combat than among males. Under patriarchy, men have held the power to propagate images and attributions which are favourable to the continuance of their control. Women's aggression has been viewed as a gender-incongruent aberration or dismissed as evidence of irrationality. These cultural interpretations have "enhanced" evolutionarily based sex differences by a process of imposition which stigmatises the expression of aggression by females and causes women to offer exculpatory (rather than justificatory) accounts of their own aggression.

  8. Research notes : zinc anodes to protect coastal bridges.

    DOT National Transportation Integrated Search

    2002-04-01

    Oregon is blessed with a beautiful coastline. Unfortunately, transportation structures on the coast must withstand an aggressive marine environment that causes corrosion problems. Many reinforced concrete bridges, some having historical significance,...

  9. Radiation methods for demercaptanization and desulfurization of oil products

    NASA Astrophysics Data System (ADS)

    Zaykina, R. F.; Zaykin, Yu. A.; Mamonova, T. B.; Nadirov, N. K.

    2002-03-01

    A two-stage method for the desulfurization of oil is presented. The first stage strongly oxidizes sulfuric material to do away with its chemical aggressiveness and promote its removal. Desulfurization of the overall product is reached at the second stage by means of conventional methods.

  10. Flat lizard female mimics use sexual deception in visual but not chemical signals

    PubMed Central

    Whiting, Martin J.; Webb, Jonathan K.; Keogh, J. Scott

    2009-01-01

    Understanding what constrains signalling and maintains signal honesty is a central theme in animal communication. Clear cases of dishonest signalling, and the conditions under which they are used, represent an important avenue for improved understanding of animal communication systems. Female mimicry, when certain males take on the appearance of females, is most commonly a male alternative reproductive tactic that is condition-dependent. A number of adaptive explanations for female mimicry have been proposed including avoiding the costs of aggression, gaining an advantage in combat, sneaking copulations with females on the territories of other males, gaining physiological benefits and minimizing the risk of predation. Previous studies of female mimicry have focused on a single mode of communication, although most animals communicate using multiple signals. Male Augrabies flat lizards adopt alternative reproductive tactics in which some males (she-males) mimic the visual appearance of females. We experimentally tested in a wild population whether she-males are able to mimic females using both visual and chemical signals. We tested chemical recognition in the field by removing scent and relabelling females and she-males with either male or female scent. At a distance, typical males (he-males) could not distinguish she-males from females using visual signals, but during close encounters, he-males correctly determined the gender of she-males using chemical signals. She-males are therefore able to deceive he-males using visual but not chemical signals. To effectively deceive he-males, she-males avoid close contact with he-males during which chemical cues would reveal their deceit. This strategy is probably adaptive, because he-males are aggressive and territorial; by mimicking females, she-males are able to move about freely and gain access to females on the territories of resident males. PMID:19324828

  11. Chemical weapon proliferation in the Middle East; time for a US regional chemical disarmament strategy. Final report

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

    Horne, W.B.

    1993-04-01

    Our experience in the Gulf War demonstrated that we cannot be sure when or where the next conflict will arise; that the world must respond to straightforward aggression; that international coalitions can be forged, though they often will require American Leadership; that the proliferation of advanced weaponry represents a clear, present, and widespread danger; and that the United States remains the nation whose strength and leadership are essential to a stable and democratic world order.

  12. Some characteristics of social interactions among adolescents in Croatia, Bosnia and Herzegovina, and Macedonia

    PubMed Central

    Klarin, Mira; Pororoković, Ana; Šašić, Slavica Šimić; Arnaudova, Violeta

    2012-01-01

    Introduction The bioecological model refers to the basic social needs that a person has satisfied through social interactions. In individualist cultures, the need for independence is emphasized with the aim of self-realization and personal achievement. In collectivist cultures, togetherness is encouraged and it prevails over individuality. Aim The aim of this study was to determine whether there were differences in adolescents (n = 1033) from three different cultural environments (Croatia, Bosnia and Herzegovina, and Macedonia) with regard to the various aspects of the social interactions and behaviors these adolescents exercise with their parents and friends. Methods Three groups of questionnaires were used: those that measure family interactions (the quality of family interactions, loneliness in the family, and family influence); those that assess peer interactions (quality of friendships, social loneliness, and influence of friendships); and those that examined behavioral variables (self-esteem, aggression, and prosocialness). Results Discriminant analysis has shown that there are two significant functions that differentiate subjects from the three different cultural environments. The first discriminant function that adequately discriminates between subjects in all three cultural environments is related to social and family loneliness and the influence of friends. Loneliness in the family, social loneliness, and influence of friends are most prevalent among adolescents in Macedonia and least among adolescents in Croatia. The second function that distinguished adolescents in Croatia from those in the other two cultural environments was primarily connected with the quality of family interactions, aggressiveness, parent influence, and self-esteem. Finally, it was found that adolescents from Bosnia and Herzegovina were more likely to engage in family interactions, have greater levels of parental influence, and appeared to be less aggressive and had lower self-esteem than adolescents from the other two regions. PMID:23172992

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

    Casella, Amanda J.; Hylden, Laura R.; Campbell, Emily L.

    Knowledge of real-time solution properties and composition is a necessity for any spent nuclear fuel reprocessing method. Metal-ligand speciation in aqueous solutions derived from the dissolved commercial spent fuel is highly dependent upon the acid concentration/pH, which influences extraction efficiency and the resulting speciation in the organic phase. Spectroscopic process monitoring capabilities, incorporated in a counter current centrifugal contactor bank, provide a pathway for on-line real-time measurement of solution pH. The spectroscopic techniques are process-friendly and can be easily configured for on-line applications, while classic potentiometric pH measurements require frequent calibration/maintenance and have poor long-term stability in aggressive chemical andmore » radiation environments. Our research is focused on developing a general method for on-line determination of pH of aqueous solutions through chemometric analysis of Raman spectra. Interpretive quantitative models have been developed and validated under the range of chemical composition and pH using a lactic acid/lactate buffer system. The developed model was applied to spectra obtained on-line during solvent extractions performed in a centrifugal contactor bank. The model predicted the pH within 11% for pH > 2, thus demonstrating that this technique could provide the capability of monitoring pH on-line in applications such as nuclear fuel reprocessing.« less

  14. Robotics crosscutting program: Technology summary

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

    NONE

    The Office of Environmental Management (EM) is responsible for cleaning up the legacy of radioactive and chemically hazardous waste at contaminated sites and facilities throughout the U.S. Department of Energy (DOE) nuclear weapons complex, preventing further environmental contamination, and instituting responsible environmental management. Initial efforts to achieve this mission resulted in the establishment of environmental restoration and waste management programs. However, as EM began to execute its responsibilities, decision makers became aware that the complexity and magnitude of this mission could not be achieved efficiently, affordably, safely, or reasonably with existing technology. Once the need for advanced cleanup technologies becamemore » evident, EM established an aggressive, innovative program of applied research and technology development. The Office of Technology Development (OTD) was established in November 1989 to advance new and improved environmental restoration and waste management technologies that would reduce risks to workers, the public, and the environment; reduce cleanup costs; and devise methods to correct cleanup problems that currently have no solutions. In 1996, OTD added two new responsibilities - management of a Congressionally mandated environmental science program and development of risk policy, requirements, and guidance. OTD was renamed the Office of Science and Technology (OST). This documents presents information concerning robotics tank waste retrieval overview, robotic chemical analysis automation, robotics decontamination and dismantlement, and robotics crosscutting and advanced technology.« less

  15. Aggression in low functioning children and adolescents with autistic disorder.

    PubMed

    Bronsard, Guillaume; Botbol, Michel; Tordjman, Sylvie

    2010-12-21

    Parents, caregivers and mental health professionals have often reported violence and aggression in children or adolescents with autistic disorder. However, most of these observations derived from anecdotal reports, and studies on frequency and characterization of aggression in autism remain limited. Our objective was to better characterize and understand the different types of aggressive behaviors displayed by a large group of individuals with autism in different observational situations. The study was conducted on 74 children and adolescents with autism and 115 typically developing control individuals matched for sex, age and pubertal stage. Other-Injurious Behaviors (OIB) were assessed in three observational situations (parents at home, two caregivers at day-care, a nurse and a child psychiatrist during blood drawing) using validated scales. The frequency of OIB was significantly higher in individuals with autism compared to typically developing control individuals during the blood drawing (23% vs. 0%, P<0 .01). The parents observed significantly less OIB in their children than caregivers (34% vs. 58%, P<0.05). In addition, the most frequent concurrent behaviors occurring just before the appearance of OIB in individuals with autism were anxiety-related behaviors and excitation according to the parental as well as the caregiver observation. The results suggest that in a stressful situation, such as the blood drawing, individuals with autism release their stress through behaviors such as OIB, whereas typically developing individuals regulate and express their stress through cognitive skills such as mental coping strategies, symbolization skills with representation and anticipation of the stressful situation, social interaction and verbal or non-verbal communication. The findings underline also the key role of the environment in assessing OIB and developing therapeutic perspectives, with an individual who modulates his/her behavior according to the environment, and an environment that perceives this behavior and reacts to it with different tolerance thresholds according to the observers.

  16. Aggression in Low Functioning Children and Adolescents with Autistic Disorder

    PubMed Central

    Bronsard, Guillaume; Botbol, Michel; Tordjman, Sylvie

    2010-01-01

    Background Parents, caregivers and mental health professionals have often reported violence and aggression in children or adolescents with autistic disorder. However, most of these observations derived from anecdotal reports, and studies on frequency and characterization of aggression in autism remain limited. Our objective was to better characterize and understand the different types of aggressive behaviors displayed by a large group of individuals with autism in different observational situations. Methodology/Findings The study was conducted on 74 children and adolescents with autism and 115 typically developing control individuals matched for sex, age and pubertal stage. Other-Injurious Behaviors (OIB) were assessed in three observational situations (parents at home, two caregivers at day-care, a nurse and a child psychiatrist during blood drawing) using validated scales. The frequency of OIB was significantly higher in individuals with autism compared to typically developing control individuals during the blood drawing (23% vs. 0%, P<0 .01). The parents observed significantly less OIB in their children than caregivers (34% vs. 58%, P<0.05). In addition, the most frequent concurrent behaviors occurring just before the appearance of OIB in individuals with autism were anxiety-related behaviors and excitation according to the parental as well as the caregiver observation. Conclusions/Significance The results suggest that in a stressful situation, such as the blood drawing, individuals with autism release their stress through behaviors such as OIB, whereas typically developing individuals regulate and express their stress through cognitive skills such as mental coping strategies, symbolization skills with representation and anticipation of the stressful situation, social interaction and verbal or non-verbal communication. The findings underline also the key role of the environment in assessing OIB and developing therapeutic perspectives, with an individual who modulates his/her behavior according to the environment, and an environment that perceives this behavior and reacts to it with different tolerance thresholds according to the observers. PMID:21200441

  17. Characterization of Laboratory Prepared Concrete Pastes Exposed to High Alkaline and High Sodium Salt Solutions

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

    Langton, C. A.

    The objective of this study was to identify potential chemical degradation mechanisms for the Saltstone Disposal Unit (SDU) concretes, which over the performance life of the structures may be exposed to highly alkaline sodium salt solutions containing sulfate, hydroxide, and other potentially corrosive chemicals in salt solution and saltstone flush water, drain water, leachate and / or pore solution. The samples analyzed in this study were cement pastes prepared in the SIMCO Technologies, Inc. concrete laboratory. They were based on the paste fractions of the concretes used to construct the Saltstone Disposal Units (SDUs). SDU 1 and 4 concrete pastesmore » were represented by the PV1 test specimens. The paste in the SDU 2, 3, 5, and 6 concrete was represented by the PV2 test specimens. SIMCO Technologies, Inc. selected the chemicals and proportions in the aggressive solutions to approximate proportions in the saltstone pore solution [2, 3, 5, and 6]. These test specimens were cured for 56 days in curing chamber before being immersed in aggressive solutions. After exposure, the samples were frozen to prevent additional chemical transport and reaction. Selected archived (retrieved from the freezer) samples were sent to the Savannah River National Laboratory (SRNL) for additional characterization using x-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive x-ray (EDX) spectroscopy. Characterization results are summarized in this report. In addition, a correlation between the oxide composition of the pastes and their chemical durability in the alkaline salt solutions is provided.« less

  18. Predicting the use of corporal punishment: Child aggression, parent religiosity, and the BDNF gene.

    PubMed

    Avinun, Reut; Davidov, Maayan; Mankuta, David; Knafo-Noam, Ariel

    2018-03-01

    Corporal punishment (CP) has been associated with deleterious child outcomes, highlighting the importance of understanding its underpinnings. Although several factors have been linked with parents' CP use, genetic influences on CP have rarely been studied, and an integrative view examining the interplay between different predictors of CP is missing. We focused on the separate and joint effects of religiosity, child aggression, parent's gender, and a valine (Val) to methionine (Met) substitution in the brain-derived neurotrophic factor (BDNF) gene. Data came from a twin sample (51% male, aged 6.5 years). We used mothers' and fathers' self-reports of CP and religiosity, and the other parent's report on child aggression. Complete data were available for 244 mothers and their 466 children, and for 217 fathers and their 409 children. The random split method was employed to examine replicability. For mothers, only the effect of religiosity appeared to replicate. For fathers, several effects predicting CP use replicated in both samples: child aggression, child sex, religiosity, and a three-way (GxExE) interaction implicating fathers' BDNF genotype, child aggression and religiosity. Religious fathers who carried the Met allele and had an aggressive child used CP more frequently; in contrast, secular fathers' CP use was not affected by their BDNF genotype or child aggression. Results were also repeated longitudinally in a subsample with age 8-9 data. Findings highlight the utility of a bio-ecological approach for studying CP use by shedding light on pertinent gene-environment interaction processes. Possible implications for intervention and public policy are discussed. © 2017 Wiley Periodicals, Inc.

  19. Rapid effects of 17β-estradiol on aggressive behavior in songbirds: Environmental and genetic influences.

    PubMed

    Heimovics, Sarah A; Merritt, Jennifer R; Jalabert, Cecilia; Ma, Chunqi; Maney, Donna L; Soma, Kiran K

    2018-04-24

    17β-estradiol (E 2 ) has numerous rapid effects on the brain and behavior. This review focuses on the rapid effects of E 2 on aggression, an important social behavior, in songbirds. First, we highlight the contributions of studies on song sparrows, which reveal that seasonal changes in the environment profoundly influence the capacity of E 2 to rapidly alter aggressive behavior. E 2 administration to male song sparrows increases aggression within 20 min in the non-breeding season, but not in the breeding season. Furthermore, E 2 rapidly modulates several phosphoproteins in the song sparrow brain. In particular, E 2 rapidly affects pCREB in the medial preoptic nucleus, in the non-breeding season only. Second, we describe studies of the white-throated sparrow, which reveal how a genetic polymorphism may influence the rapid effects of E 2 on aggression. In this species, a chromosomal rearrangement that includes ESR1, which encodes estrogen receptor α (ERα), affects ERα expression in the brain and the ability of E 2 to rapidly promote aggression. Third, we summarize studies showing that aggressive interactions rapidly affect levels of E 2 and other steroids, both in the blood and in specific brain regions, and the emerging potential for steroid profiling by liquid chromatography tandem mass spectrometry (LC-MS/MS). Such studies of songbirds demonstrate the value of an ethologically informed approach, in order to reveal how steroids act rapidly on the brain to alter naturally-occurring behavior. Copyright © 2018. Published by Elsevier Inc.

  20. Chemical characterization of particulate air pollutants Case studies on indoor air quality, cultural heritage and the marine environment

    NASA Astrophysics Data System (ADS)

    Horemans, Benjamin

    When attempting to discuss the effects of airborne particulate matter (PM), it is important to address both physical and chemical aspects of this pollutant. This work reports on the results of three separate case studies, each approaching a specific problem of air pollution by evaluating the chemical composition of PM. 1. In the US and Europe, office workers often complain about work-related health symptoms. These symptoms are collectively referred as the 'sick building syndrome'. This work could be considered as one of the largest data collections on particulate pollutants in Belgian offices. It helps to understand the sources as well as the behavior and fate of PM at our workplace environments. Especially the chemical information on PM makes the results unique, since it enables a better evaluation of the health risks connected to office dust. 2. The Alhambra and Generalife bring every year more than 3 million people to Granada in Southern Spain. Recently, the increasing urbanization of Granada and the immense pressure of mass tourism form a threat for this heritage. Despite the fact that atmospheric pollutants are known to he potentially aggressive for our cultural patrimony. this case study is the first to assess the effects of environmental aerosols on the Alhambra monument. The results of this study could help decision-makers at the Alhambra and the city of Granada with the formulation of preventive conservation measures. They show how local vehicular traffic is the main source for atmospheric pollution in and around the Alhambra monument. Targeted strategies are necessary in order to maximally preserve these monuments and their UNESCO world cultural heritage label. 3. Excessive input of nitrogen-containing atmospheric nutrients via dry and wet deposition can cause entrophication of marine regions, which is also a common, seasonal phenomenon along the coasts of the North Sea. This study is the first to give a complete quantitative description of the atmospheric input of N-nutrients to Belgian coastal waters of the North Sea. Especially the detailed information on the partitioning of N-species over various phases (gas, aerosol, precipitation) and the extend of the data set make these results unique.

  1. Ailanthus altissima interfers with beneficial symbionts and negetively [sic] impacts oak regeneration

    Treesearch

    Jenise M. Bauman; Caitlin Byrne; Shiv Hiremath

    2013-01-01

    The invasion of Tree-of-Heaven (Ailanthus altissima) has been documented in disturbed landscapes leading to biodiversity loss and degradation of ecosystem function. Ailanthus interferes with the restoration of native species by its aggressive growth habit, alteration of nutrient cycles, and allelopathic chemical production. Recent...

  2. Chemical Characterization and Thermal Stressing Studies of Perfluorohexane Fluids for Space-Based Applications

    NASA Technical Reports Server (NTRS)

    Arnold, William A.; Hartman, Thomas G.; McQuillen, John

    2006-01-01

    Perfluorohexane (PFH), C6F14, is a perfluorocarbon fluid. Several PFH fluids with different isomer concentrations were evaluated for use in an upcoming NASA space experiment. Samples tested included two commercially obtained high-purity n-perfluorohexane (n-PFH) fluids and a technical grade mixture of C6F14 branched and linear isomers (FC-72(TradeMark)). These fluids were evaluated for exact chemical composition, impurity purity and high temperature degradation behavior (pyrolysis). Our investigation involved simulated thermal stressing studies of PFH fluids under conditions likely to occur in the event of an atmospheric breach within the International Space Station (ISS) and subsequent exposure of the vapors to the high temperature and catalyst present in its Trace Contaminant Control Subsystem (TCCS). Exposure to temperatures in the temperature range of 200-450 C in an inert or oxidizing atmosphere, with and without the presence of catalyst was investigated. The most aggressive conditions studied were exposure of PFH vapors to 450 C in air and in the presence of TCCS (palladium) catalyst. Gas chromatography-mass spectrometry (GC-MS) and gas chromatography (GC) analyses were conducted on the perfluorohexane samples before and after pyrolysis. The FC-72 and n-PFH samples showed no significant degradation following pyrolysis even under the most aggressive study conditions. Some trace level impurities associated with the PFH samples such as linear perfluorocarbon monohydrides or monoiodides were destroyed by pyrolysis at the upper limit. Other trace level impurities such as olefinic or cycloolefinic perfluorocarbons were converted into oxidation products by pyrolysis. The purity of PFH following pyrolysis actually increased slightly as a consequence since these trace contaminants were effectively scrubbed from the samples. However, since the initial concentrations of the thermally-impacted impurities were so low, the net effect was trivial. A potential byproduct of exposure of perfluorohexane fluids to high temperatures is the production of perfluoroisobutene (PFiB), which is extremely toxic. An ultra-high sensitivity PFiB-specific analysis based on GC-MS with negative ion chemical ionization (NICI) detection was used to evaluate the samples following thermal stressing. The perfluorohexanes examined here under conditions reflective of the ISS TCCS environment showed no signs of PFiB production with an analytical detection limit of 10 part per billion (ppb v/v).

  3. X-RAY DENSITOMETRY OF NORWAY SPRUCE SUBFOSSIL WOOD FROM THE AUSTRIAN ALPS

    PubMed Central

    KŁUSEK, MARZENA; GRABNER, MICHAEL

    2016-01-01

    The processing of subfossil wood poses some difficulties in densitometric research. Problems arise because of the physio-chemical changes of wood occurring in the sedimentation environment. Subfossil wood modification can result from the uptake of mineral and organic substances into the wood tissue. It can also occur as the effect of microbiological degradation of wood. The goal of this study was to identify the appropriate method of subfossil wood preparation for the densitometric research. For this purpose the wood of Norway spruce from Lake Schwarzensee was subjected to extraction in deionized water, acetone and diluted acetic acid. The application of acetic acid did not significantly influence the density of the wood and acetone seemed to be too aggressive. The best result was obtained by rinsing the samples in cold de-ionized water. This extraction procedure allowed removal of unwanted water-soluble, organic and inorganic compounds from wood and simultaneously did not lead to the degradation of subfossil samples. PMID:27158247

  4. Analysis of Corrosion Residues Collected from the Aluminum Basket Rails of the High-Burnup Demonstration Cask.

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

    Bryan, Charles R.

    On September, 2015, an inspection was performed on the TN-32B cask that will be used for the high-burnup demonstration project. During the survey, wooden cribbing that had been placed within the cask eleven years earlier to prevent shifting of the basket during transport was removed, revealing two areas of residue on the aluminum basket rails, where they had contacted the cribbing. The residue appeared to be a corrosion product, and concerns were raised that similar attack could exist at more difficult-to-inspect locations in the canister. Accordingly, when the canister was reopened, samples of the residue were collected for analysis. Thismore » report presents the results of that assessment, which determined that the corrosion was due to the presence of the cribbing. The corrosion was associated with fungal material, and fungal activity likely contributed to an aggressive chemical environment. Once the cask has been cleaned, there will be no risk of further corrosion.« less

  5. TRI: Growing pains

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

    Fairley, P.

    1996-06-12

    The 1994 toxics release inventory (TRI), scheduled to be released this week by EPA, will be the last before an aggressive expansion mapped out by EPA Administrator Carol Browner. By August 1, facilities must report on emissions and transfers of about 280 chemicals that were added to TRI in November 1994, nearly doubling the list. The changes could greatly increase the chemical industry`s TRI numbers, and there is more to come. This summer EPA is expected to formally propose extending TRI to nonmanufacturing facilities, such as power plants and airports. President Clinton has ordered EPA to expedite consideration of phasemore » III of Browner`s expansion: chemical use reporting under TRI.« less

  6. Social context rather than behavioral output or winning modulates post-conflict testosterone responses in Japanese quail (Coturnix japonica).

    PubMed

    Hirschenhauser, K; Wittek, M; Johnston, P; Möstl, E

    2008-10-20

    Testosterone regulates the expression of sexual and aggressive behavior in male vertebrates and treatments with testosterone may promote territorial aggression and winning in dyadic contests. Conversely, individual testosterone levels respond to sexual or aggressive interactions and the social environment. Post-conflict testosterone in winner males though appears to be more complex than simply reflecting conflict outcome. Expression and degree of post-conflict testosterone responses may adapt to additional modulators such as repeated winning experience, audience presence, opponent's fighting ability, and self-assessment. We present simulated intrusion experiments with male Japanese quail using mirror-elicited aggression and fights with real opponents ('direct challenge'). We recorded agonistic behavior and measured immunoreactive testosterone metabolites (TM) non-invasively from individual droppings. Frequencies of initiated agonistic behavior were similar whether towards the mirror or in direct challenge tests, although some of the males were behaviorally non-responsive to the mirror ('mirror submissives'). However, there was no TM response to the mirror test in both, mirror fighters and mirror submissives, thus independently of behavioral output. After direct challenges TM levels were elevated in all males (focal males winning or conflict unresolved after 30 min), hence independently of conflict outcome. Thus, in male quail a combination of physical stimuli and the individual perception of own and opponent's fighting ability explained the expression of post-conflict TM responses rather than behavioral performance, conflict outcome, or any of these factors alone. In sum, our results emphasize that the degree of androgen responsiveness to agonistic behavior is fine-tuned by components related with social context and environment.

  7. Adaptive shaping of the behavioural and neuroendocrine phenotype during adolescence

    PubMed Central

    Kaiser, Sylvia; Hennessy, Michael B.; Sachser, Norbert

    2017-01-01

    Environmental conditions during early life can adaptively shape the phenotype for the prevailing environment. Recently, it has been suggested that adolescence represents an additional temporal window for adaptive developmental plasticity, though supporting evidence is scarce. Previous work has shown that male guinea pigs living in large mixed-sex colonies develop a low-aggressive phenotype as part of a queuing strategy that is adaptive for integrating into large unfamiliar colonies. By contrast, males living in pairs during adolescence become highly aggressive towards strangers. Here, we tested whether the high-aggressive phenotype is adaptive under conditions of low population density, namely when directly competing with a single opponent for access to females. For that purpose, we established groups of one pair-housed male (PM), one colony-housed male (CM) and two females. PMs directed more aggression towards the male competitor and more courtship and mating towards females than did CMs. In consequence, PMs attained the dominant position in most cases and sired significantly more offspring. Moreover, they showed distinctly higher testosterone concentrations and elevated cortisol levels, which probably promoted enhanced aggressiveness while mobilizing necessary energy. Taken together, our results provide the clearest evidence to date for adaptive shaping of the phenotype by environmental influences during adolescence. PMID:28202817

  8. Aggressive desert goby males also court more, independent of the physiological demands of salinity.

    PubMed

    Lehtonen, Topi K; Svensson, P Andreas; Wong, Bob B M

    2018-06-19

    Both between- and within-individual variation in behaviour can be important in determining mating opportunities and reproductive outcomes. Such behavioural variability can be induced by environmental conditions, especially if individuals vary in their tolerance levels or resource allocation patterns. We tested the effects of exposure to different salinity levels on male investment into two important components of mating success-intrasexual aggression and intersexual courtship-in a fish with a resource defence mating system, the desert goby, Chlamydogobius eremius. We found that males that were more aggressive to rivals also exhibited higher rates of courtship displays towards females. Contrary to predictions, this positive relationship, and the consistency of the two behaviours, were not affected by the salinity treatment, despite the physiological costs that high salinity imposes on the species. Moreover, over the entire data-set, there was only a marginally non-significant tendency for males to show higher levels of aggression and courtship in low, than high, salinity. The positive correlation between male aggression and courtship, independent of the physiological demands of the environment, suggests that males are not inclined to make contrasting resource investments into these two key reproductive behaviours. Instead, in this relatively euryhaline freshwater species, typical investment into current reproductive behaviours can occur under a range of different salinity conditions.

  9. Hippocampal volume and sensitivity to maternal aggressive behavior: a prospective study of adolescent depressive symptoms.

    PubMed

    Whittle, Sarah; Yap, Marie B H; Sheeber, Lisa; Dudgeon, Paul; Yücel, Murat; Pantelis, Christos; Simmons, Julian G; Allen, Nicholas B

    2011-02-01

    It has been suggested that biological factors confer increased sensitivity to environmental influences on depressive symptoms during adolescence, a crucial time for the onset of depressive disorders. Given the critical role of the hippocampus in sensitivity to stress and processing of contextual aspects of the environment, investigation of its role in determining sensitivity to environmental context seems warranted. This study prospectively examined hippocampal volume as a measure of sensitivity to the influence of aggressive maternal behavior on change in depressive symptoms from early to midadolescence. The interaction between aggressive maternal behavior and hippocampal volume was found to predict change in depressive symptoms. Significant sex differences also emerged, whereby only for girls were larger bilateral hippocampal volumes more sensitive to the effects of maternal aggressive behavior, particularly with respect to experiencing the protective effects of low levels of maternal aggressiveness. These findings help elucidate the complex relationships between brain structure, environmental factors such as maternal parenting style, and sensitivity to (i.e., risk for, and protection from) the emergence of depression during this life stage. Given that family context risk factors are modifiable, our findings suggest the potential utility of targeted parenting interventions for the prevention and treatment of adolescent depressive disorder.

  10. Associations between bullying and engaging in aggressive and suicidal behaviors among sexual minority youth: the moderating role of connectedness.

    PubMed

    Duong, Jeffrey; Bradshaw, Catherine

    2014-10-01

    Research on the extent to which cyberbullying affects sexual minority youth is limited. This study examined associations between experiencing cyber and school bullying and engaging in aggressive and suicidal behaviors among sexual minority youth. We also explored whether feeling connected to an adult at school moderated these associations. Data came from 951 self-identified lesbian, gay, and bisexual (LGB) youth, who completed the New York City Youth Risk Behavior Survey during fall 2009. We used multiple logistic regression to examine the hypothesized associations and test for effect modification. Cyber and school bullying were associated with engaging in aggressive and suicidal behaviors among LGB youth. Youth experiencing both cyber and school bullying had the greatest odds of engaging in aggressive and suicidal behaviors. However, feeling connected to an adult at school moderated these associations such that bullied youth who felt connected were not more likely to report aggressive and suicidal behaviors. The findings highlight the challenges faced by bullied LGB youth. Practitioners should work with school administrators to establish supportive environments for sexual minority youth. Helping victimized LGB youth develop meaningful connections with adults at school can minimize the negative impacts of cyber and school bullying. © 2014, American School Health Association.

  11. Children and adolescents facing a continuous security threat: Aggressive behavior and post-traumatic stress symptoms.

    PubMed

    Nuttman-Shwartz, Orit

    2017-07-01

    There is extensive research evidence indicating that children and youth are the most vulnerable population for developing psychological symptoms relating to war and terror. Although studies have documented a wide range of detrimental emotional and behavioral effects of such exposure, much less is known about the effects of exposure to a continuous security threat for children and adolescents. Against this background, the current article examined the implications of continuous exposure to missile attacks among 1096 children and adolescents enrolled in public schools near the Israeli border with Gaza. Participants filled out quantitative questionnaires, which relate to the pathological consequences of continuous exposure to security threats, and to the role of the school and the community as a protective environment against disruptive behavior resulting from such exposure. The findings revealed that PTSS responses were mainly related to the security threat, whereas interpersonal aggression resulted from other types of traumatic events. Significant differences were found between aggression and posttraumatic symptoms, by age and gender. PTSS was found to be lower for older participants and higher for girls, whereas aggression was higher for boys and higher for older participants. Furthermore, the sense of belonging to the place of residence was negatively associated with PTSS as well as with aggressive behavior: the higher the participants' sense of belonging, the lower their levels of PTSS and aggressive responses. In contrast, the sense of belonging to the school was negatively associated only with aggressive behavior: the higher the participants' sense of belonging to the school, the lower their aggressive responses. The findings are discussed in the light of trauma theories and in light of the results of previous research. The study contributed to knowledge about the differential consequences of exposure to a security threat, and highlighted the importance of differential interventions with children who show post-traumatic symptoms versus those who show aggressive behavior. Accordingly, the security situation should not overshadow social issues that need to be addressed, such as family violence and aggression among school children. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Trait aggressiveness does not predict social dominance of rats in the Visible Burrow System.

    PubMed

    Buwalda, Bauke; Koolhaas, Jaap M; de Boer, Sietse F

    2017-09-01

    Hierarchical social status greatly influences health and well-being in mammals, including humans. The social rank of an individual is established during competitive encounters with conspecifics. Intuitively, therefore, social dominance and aggressiveness may seem intimately linked. Yet, whether an aggressive personality trait may predispose individuals to a particular rank in a social colony setting remains largely unclear. Here we tested the hypothesis that high trait aggressiveness in Wildtype Groningen (WTG) rats, as assessed in a classic resident-intruder offensive aggression paradigm predicts social dominance in a mixed-sex colony housing using the Visible Burrow System (VBS). We also hypothesized that hierarchical steepness, as reflected in the number and intensity of the social conflicts, positively correlates with the average level of trait aggressiveness of the male subjects in the VBS. Clear and stable hierarchical ranking was formed within a few days in VBS colonies as indicated and reflected by a rapid loss of body weight in subordinates which stabilized after 2-3days. Social conflicts, that occurred mainly during these first few days, also resulted in bite wounds in predominantly subordinate males. Data clearly showed that trait aggressiveness does not predict dominance status. The most aggressive male in a mixed sex group of conspecifics living in a closed VBS environment does not always become the dominant male. In addition, data did not convincingly indicate that in colonies with only highly aggressive males, agonistic interactions were more intense. Number of bite wounds and body weight loss did not positively correlate with trait-aggressiveness of subordinates. In this study, rats from this wild-derived rat strain behave differently from Long-Evans laboratory rats that have been studied up till now in many experiments using the VBS. Strain dependent differences in the capacity to display appropriate social behavior fitting an adaptive strategy to a high or low social ranking position probably play an important role in the level of perceived stress in mixed sex social colonies like the VBS. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. Reassessment of True Core Collapse Differential Pressure Values for Filter Elements in Safety Critical Environments - 13076

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

    Swain, Adam

    2013-07-01

    As the areas of application for diverse filter types increases, the mechanics and material sciences associated with the hardware and its relationship with more and more arduous process environments becomes critical to the successful and reliable operation of the filtration equipment. Where the filter is the last safe barrier between the process and the life environment, structural integrity and reliability is paramount in both the validation and the ethical acceptability of the designed equipment. Core collapse is a key factor influencing filter element selection, and is an extremely complex issue with a number of variables and failure mechanisms. It ismore » becoming clear that the theory behind core collapse calculations is not always supported with real tested data. In exploring this issue we have found that the calculation method is not always reflective of the true as tested collapse value, with the calculated values being typically in excess or even an order of magnitude higher than the tested values. The above claim is supported by a case study performed by the author, which disproves most of what was previously understood to be true. This paper also aims to explore the various failure mechanisms of different configurations of filter core, comparing calculated collapse values against real tested values, with a view to understanding a method of calculating their true collapse value. As the technology is advancing, and filter elements are being used in higher temperature, higher pressure, more radioactive and more chemically aggressive environments, confidence in core collapse values and data is crucial. (authors)« less

  14. The influence of social environment in early life on the behavior, stress response, and reproductive system of adult male Norway rats selected for different attitudes to humans.

    PubMed

    Gulevich, R G; Shikhevich, S G; Konoshenko, M Yu; Kozhemyakina, R V; Herbeck, Yu E; Prasolova, L A; Oskina, I N; Plyusnina, I Z

    2015-05-15

    The influence of social disturbance in early life on behavior, response of blood corticosterone level to restraint stress, and endocrine and morphometric indices of the testes was studied in 2-month Norway rat males from three populations: not selected for behavior (unselected), selected for against aggression to humans (tame), and selected for increased aggression to humans (aggressive). The experimental social disturbance included early weaning, daily replacement of cagemates from days 19 to 25, and subsequent housing in twos till the age of 2months. The social disturbance increased the latent period of aggressive behavior in the social interaction test in unselected males and reduced relative testis weights in comparison to the corresponding control groups. In addition, experimental unselected rats had smaller diameters of seminiferous tubules and lower blood testosterone levels. In the experimental group, tame rats had lower basal corticosterone levels, and aggressive animals had lower hormone levels after restraint stress in comparison to the control. The results suggest that the selection in two directions for attitude to humans modifies the response of male rats to social disturbance in early life. In this regard, the selected rat populations may be viewed as a model for investigation of (1) neuroendocrinal mechanisms responsible for the manifestation of aggression and (2) interaction of the hypothalamic-pituitary-adrenal and hypothalamic-pituitary-gonadal systems in stress. Copyright © 2015 Elsevier Inc. All rights reserved.

  15. Investigation of carbon fiber composite cables (CFCC) in prestressed concrete piles.

    DOT National Transportation Integrated Search

    2014-04-01

    The Florida Department of Transportation (FDOT) commonly uses prestressed concrete piles in : bridge foundations. These piles are prestressed with steel strands that, when installed in aggressive or : marine environments, are subject to corrosion and...

  16. Effect of Atmospheric Corrosion on the Mechanical Properties of SAE 1020 Structural Steel.

    PubMed

    Martínez, Carola; Briones, Francisco; Villarroel, María; Vera, Rosa

    2018-04-11

    Resistance to atmospheric corrosion in different environments located in Chile and the corrosion's effect on the mechanical properties of SAE 1020 steel were studied. Atmospheric corrosivity categories at each station under study were determined. These categories were C2, for Laja; C3 and C4, for the Arica and Antarctic stations, respectively; and the most aggressive, C5 and higher at Quintero. These specific environments significantly influenced the mechanical responses of steel exposed for 36 months. Rupture elongation, the modulus of toughness, ultimate tensile strength, and hardness of the material all decreased as a function of environmental atmospheric aggressiveness. Lowered ductility is the result of the increased corrosion rate due to the high deposition of chlorides. This is due to the morphology of material degradation, which consequently occurs as pores, microstrains, and other defects that promote early rupture of the steel.

  17. Effect of Atmospheric Corrosion on the Mechanical Properties of SAE 1020 Structural Steel

    PubMed Central

    Briones, Francisco; Villarroel, María; Vera, Rosa

    2018-01-01

    Resistance to atmospheric corrosion in different environments located in Chile and the corrosion’s effect on the mechanical properties of SAE 1020 steel were studied. Atmospheric corrosivity categories at each station under study were determined. These categories were C2, for Laja; C3 and C4, for the Arica and Antarctic stations, respectively; and the most aggressive, C5 and higher at Quintero. These specific environments significantly influenced the mechanical responses of steel exposed for 36 months. Rupture elongation, the modulus of toughness, ultimate tensile strength, and hardness of the material all decreased as a function of environmental atmospheric aggressiveness. Lowered ductility is the result of the increased corrosion rate due to the high deposition of chlorides. This is due to the morphology of material degradation, which consequently occurs as pores, microstrains, and other defects that promote early rupture of the steel. PMID:29641490

  18. Corrosion-Fatigue Crack Growth in Plates: A Model Based on the Paris Law

    PubMed Central

    Toribio, Jesús; Matos, Juan-Carlos; González, Beatriz

    2017-01-01

    In this paper, a Paris law-based model is presented whereby crack propagation occurs under cyclic loading in air (fatigue) and in an aggressive environment (corrosion-fatigue) for the case of corner cracks (with a wide range of aspect ratios in the matter of the initial cracks) in finite-thickness plates of 316L austenitic stainless steel subjected to tension, bending, or combined (tension + bending) loading. Results show that the cracks tend during their growth towards a preferential propagation path, exhibiting aspect ratios slightly lower than unity only for the case of very shallow cracks, and diminishing as the crack grows (increasing the relative crack depth)—more intensely in the case of bending than in the case of tension (the mixed loading tension/bending representing an intermediate case). In addition, the crack aspect ratios during fatigue propagation evolution are lower in fatigue (in air) than in corrosion-fatigue (in aggressive environment). PMID:28772798

  19. Maternal distress explains the relationship of young African American mothers' violence exposure with their preschoolers' behavior.

    PubMed

    Mitchell, Stephanie J; Lewin, Amy; Rasmussen, Andrew; Horn, Ivor B; Joseph, Jill G

    2011-02-01

    Adolescent mothers and their children are particularly susceptible to witnessing or directly experiencing violence. Such violence exposure predicts maternal distress, parenting, and child behavior problems. The current study examined how mothers' depressive symptoms, aggression, harsh disciplinary practices, and home environment independently explain the association between mothers' violence exposure and children's externalizing and internalizing behavior, controlling for their children's violence exposure. Data were collected from 230 African American mothers living in Washington, DC who gave birth as adolescents and whose children were 3 to 5 years old. Path analysis revealed that the effect of mothers' experienced violence on children's externalizing and internalizing behavior was mediated by mothers' depressive symptoms and aggression. However, neither harsh discipline nor stimulation in the home environment acted as significant mediators, and there were no direct or indirect effects of mothers' witnessed violence on child behavior. This study builds on previous work by identifying an association between maternal violence exposure and children's behavior, independent of children's own violence exposure that is explained by mothers' increased distress but not their parenting. These findings suggest that a potential means of preventing behavior problems in minority children born to adolescent mothers is to identify mothers who have been directly exposed to violence and treat their depressive symptoms and aggressive behaviors.

  20. The effect of adult aggression on habitat selection by settlers of two coral-dwelling damselfishes.

    PubMed

    Ben-Tzvi, Ofer; Kiflawi, Moshe; Polak, Omer; Abelson, Avigdor

    2009-01-01

    Coral-reef fishes experience a major challenge when facing settlement in a multi-threat environment, within which, using settlement cues, they need to select a suitable site. Studies in laboratories and artificial setups have shown that the presence of conspecific adults often serves as a positive settlement cue, whose value is explained by the increased survival of juveniles in an already proven fit environment. However, settlement in already inhabited corals may expose the recruits to adult aggression. Daily observations and manipulation experiments were used in the present study, which was conducted in the natural reef. We revealed differential strategies of settlers, which do not necessarily join conspecific adults. Dascyllus aruanus prefer to settle near (not with) their aggressive adults, and to join them only after gaining in size; whereas Dascyllus marginatus settlers in densely populated reefs settle independently of their adult distribution. Our results present different solutions to the challenges faced by fish recruits while selecting their microhabitat, and emphasize the complexity of habitat selection by the naïve settlers. Although laboratory experiments are important to the understanding of fish habitat selection, further studies in natural habitats are essential in order to elucidate the actual patterns of settlement and habitat selection, which are crucial for the survival of coral-reef fish populations.

  1. Interactions between chloride and cement-paste materials.

    PubMed

    Barberon, Fabien; Baroghel-Bouny, Véronique; Zanni, Hélène; Bresson, Bruno; d'Espinose de la Caillerie, Jean-Baptiste; Malosse, Lucie; Gan, Zehong

    2005-02-01

    The durability of cement-based materials with respect to exterior aggressions is one of the current priorities in civil engineering. Depending on their use, the cement-based materials can be exposed to different types of aggressive environments. For instance, damages to concrete structures in contact with a saline environment (sea water on bridges, deicing salts on roads, etc.) are of utmost importance. Upon exposure to saline water, Cl- ions penetrate into the structures and subsequently lead to reinforcement corrosion. Chloride attack is often combined with other aggressive influences such as temperature (e.g., freezing) or the ingress of other ions (e.g., sulfates in sea water). We therefore aim to explore the effect of sodium chloride (NaCl) on the structural chemistry of cement paste. Existing studies about reinforcement corrosion by chloride have focused on the penetration of Cl- ions and the comparison between "free" ions (water-soluble ions) and bound ones. However, little is known about the fixation mechanisms, the localization of Cl in the cement matrix and the structural interaction between Cl and the silicate and aluminate hydrate phases present in cement paste. We present here results of a multinuclear nuclear magnetic resonance study on the fixation of chloride in the hydration products and the characterization of new phases potentially appearing due to chloride ingress.

  2. Struggling for legitimacy: nursing students' stories of organisational aggression, resilience and resistance.

    PubMed

    Jackson, Debra; Hutchinson, Marie; Everett, Bronwyn; Mannix, Judy; Peters, Kath; Weaver, Roslyn; Salamonson, Yenna

    2011-06-01

    There is a considerable body of literature scrutinising and theorising negative and hostile behaviour such as violence and interpersonal conflict in the nursing workplace. However, relatively little empirical work has examined the experiences of undergraduate nursing students in the context of negative workplace cultures, and even fewer studies have explored how students develop and enact strategies to counter hostile behaviours in the clinical workplace. Based on qualitative analysis of open-ended survey questions, this study explored undergraduate students' experiences of negative behaviours in the clinical environment to identify strategies used to manage and resist such behaviours. While dominant individuals in the clinical environment sought to enforce and uphold their version of legitimacy--one where students were relegated to complete subordination--the tenacity and resourcefulness of students was evident in their attempts to counter this oppression with acts of resistance. Our findings provide new and valuable insights into organisational aggression and acts of resistance in the nursing workplace. The resistance offered by these students draws attention to the struggles for legitimacy within institutions. In drawing attention to organisational aggression as a mechanism by which students are 'othered' through pejorative behaviour, homogenisation, and de-authentication, and the dynamics of resistance offered by these student nurses, we provide an alternative explanation of nursing socialisation. © 2011 Blackwell Publishing Ltd.

  3. Influence of aggressive ions on the degradation behavior of biomedical magnesium alloy in physiological environment.

    PubMed

    Xin, Yunchang; Huo, Kaifu; Tao, Hu; Tang, Guoyi; Chu, Paul K

    2008-11-01

    Various electrochemical approaches, including potentiodynamic polarization, open circuit potential evolution and electrochemical impedance spectroscopy (EIS), are employed to investigate the degradation behavior of biomedical magnesium alloy under the influence of aggressive ions, such as chloride, phosphate, carbonate and sulfate, in a physiological environment. The synergetic effects and mutual influence of these ions on the degradation behavior of Mg are revealed. Our results demonstrate that chloride ions can induce porous pitting corrosion. In the presence of phosphates, the corrosion rate decreases and the formation of pitting corrosion is significantly delayed due to precipitation of magnesium phosphate. Hydrogen carbonate ions are observed to stimulate the corrosion of magnesium alloy during the early immersion stage but they can also induce rapid passivation on the surface. This surface passivation behavior mainly results from the fast precipitation of magnesium carbonate in the corrosion product layer that can subsequently inhibit pitting corrosion completely. Sulfate ions are also found to stimulate magnesium dissolution. These results improve our understanding on the degradation mechanism of surgical magnesium in the physiological environment.

  4. Graphene Electronic Device Based Biosensors and Chemical Sensors

    NASA Astrophysics Data System (ADS)

    Jiang, Shan

    Two-dimensional layered materials, such as graphene and MoS2, are emerging as an exciting material system for a new generation of atomically thin electronic devices. With their ultrahigh surface to volume ratio and excellent electrical properties, 2D-layered materials hold the promise for the construction of a generation of chemical and biological sensors with unprecedented sensitivity. In my PhD thesis, I mainly focus on graphene based electronic biosensors and chemical sensors. In the first part of my thesis, I demonstrated the fabrication of graphene nanomesh (GNM), which is a graphene thin film with a periodic array of holes punctuated in it. The periodic holes introduce long periphery active edges that provide a high density of functional groups (e.g. carboxylic groups) to allow for covalent grafting of specific receptor molecules for chemical and biosensor applications. After covalently functionalizing the GNM with glucose oxidase, I managed to make a novel electronic sensor which can detect glucose as well as pH change. In the following part of my thesis I demonstrate the fabrication of graphene-hemin conjugate for nitric oxide detection. The non-covalent functionalization through pi-pi stacking interaction allows reliable immobilization of hemin molecules on graphene without damaging the graphene lattice to ensure the highly sensitive and specific detection of nitric oxide. The graphene-hemin nitric oxide sensor is capable of real-time monitoring of nitric oxide concentrations, which is of central importance for probing the diverse roles of nitric oxide in neurotransmission, cardiovascular systems, and immune responses. Our studies demonstrate that the graphene-hemin sensors can respond rapidly to nitric oxide in physiological environments with sub-nanomolar sensitivity. Furthermore, in vitro studies show that the graphene-hemin sensors can be used for the detection of nitric oxide released from macrophage cells and endothelial cells, demonstrating their practical functionality in complex biological systems. In the last part of my thesis, I demonstrate the construction of few-layer molybdenum disulfide (MoS2) based field-effect transistor (FET) device for highly sensitive detection of Hg2+ ion in aquatic solutions. The detection of mercury in aquatic environment is of great importance because mercury is an environment pollutant with severe toxicity. High binding affinity between mercury and sulfur makes MoS2 a promising candidate for mercury sensing. Our studies demonstrate that MoS2 sensors can selectively respond to Hg2+ ion with a detection limit of 30 pM. This MoS2 FET based mercury sensor promises great potential for highly sensitive, label-free, low-cost, fast and non-aggressive detection of mercury in aquatic environment.

  5. A Cyberspace Command and Control Model (Maxwell Paper, Number 47)

    DTIC Science & Technology

    2009-08-01

    mand [for] Network Warfare [JFCC-NW]).ŗ This arrange- ment further creates gaps and seams as the DOD attempts, through a traditional, hierarchical...pervasiveness of cyberspace coupled with aggressive adversaries create a volatile environment. The DOD. along with the rest of the world, is...these factors, along with the challenges of attributing cyberspace intrusions, combine to create an environment of frustrating ambiguity. The correct

  6. A Cyberspace Command and Control Model

    DTIC Science & Technology

    2009-02-17

    control of Commander, Joint Functional Component Commander – Network Warfare (JFCC-NW).3 This arrangement further creates gaps and seams as the DoD...technological advances and increases in the use and pervasiveness of cyberspace coupled with aggressive 5 adversaries create a volatile environment. Both...intrusions, combine to create an environment of frustrating ambiguity. The correct military response lies in establishing a C2 structure for this

  7. The effects of the dopamine stabilizer (-)-OSU6162 on aggressive and sexual behavior in rodents.

    PubMed

    Studer, E; Näslund, J; Westman, A; Carlsson, A; Eriksson, E

    2016-03-22

    The dopamine stabilizer (-)-OSU61612 dampens locomotion in rodents rendered hyperactive by exposure to a novel environment or treatment with amphetamine, but stimulates locomotion in habituated animals displaying low motor activity, tentatively exerting this profile by selectively blocking extrasynaptic D2 receptors. The major aim of the present study was to explore the possible usefulness of (-)-OSU61612 as an anti-aggressive drug. To this end, the effect of (-)-OSU61612 on isolation-induced aggression in male mice and estrous cycle-dependent aggression in female rats were studied using the resident intruder test; in addition, the possible influence of (-)-OSU61612 on sexual behavior in male mice and on elevated plus maze (EPM) performance in male rats were assessed. (-)-OSU61612 at doses influencing neither locomotion nor sexual activity reduced aggression in male mice. The effect was observed also in serotonin-depleted animals and is hence probably not caused by the antagonism of serotonin receptors displayed by the drug; refuting the possibility that it is due to 5-HT1B activation, it was also not counteracted by isamoltane. (-)-OSU61612 did not display the profile of an anxiogenic or anxiolytic drug in the EPM but caused a general reduction in activity that is well in line with the previous finding that it reduces exploratory behavior of non-habituated animals. In line with the observations in males, (-)-OSU61612 reduced estrus cycle-related aggression in female Wistar rats, a tentative animal model of premenstrual dysphoria. By stabilizing dopaminergic transmission, (-)-OSU61612 may prove useful as a well-tolerated treatment of various forms of aggression and irritability.

  8. Interacting effect of MAOA genotype and maternal prenatal smoking on aggressive behavior in young adulthood.

    PubMed

    Hohmann, Sarah; Zohsel, Katrin; Buchmann, Arlette F; Blomeyer, Dorothea; Holz, Nathalie; Boecker-Schlier, Regina; Jennen-Steinmetz, Christine; Rietschel, Marcella; Witt, Stephanie H; Schmidt, Martin H; Esser, Günter; Meyer-Lindenberg, Andreas; Banaschewski, Tobias; Brandeis, Daniel; Hohm, Erika; Laucht, Manfred

    2016-08-01

    Findings on the etiology of aggressive behavior have provided evidence for an effect both of genetic factors, such as variation in the monoamine oxidase A (MAOA) gene, and adverse environmental factors. Recent studies have supported the existence of gene × environment interactions, with early experiences playing a key role. In the present study, the effects of prenatal nicotine exposure, MAOA genotype and their interaction on aggressive behavior during young adulthood were examined. In a sample of 272 young adults (129 males, 143 females) from an epidemiological cohort study, smoking during pregnancy was measured with a standardized parent interview at the offspring's age of 3 months. Aggressive behavior was assessed between the ages of 19 and 25 years using the Young Adult Self-Report. DNA was genotyped for the MAOA 5' untranslated region variable number of tandem repeats polymorphism (VNTR). Results revealed a significant interaction between MAOA and smoking during pregnancy, indicating higher levels of aggressive behavior in young adults carrying the MAOA low-expressing genotype who had experienced prenatal nicotine exposure (n = 8, p = .025). In contrast, in carriers of the MAOA high-expressing genotype, maternal smoking during pregnancy had no effect on aggressive behavior during young adulthood (n = 20, p = .145). This study extends earlier findings demonstrating an interaction between MAOA genotype and prenatal nicotine exposure on aggressive behavior into young adulthood. The results point to the long-term adverse effects of smoking during pregnancy on the offspring's mental health, possibly underlining the importance of smoking cessation during pregnancy. According to the nature of the study (particularly sample size and power), analyses are exploratory and results need to be interpreted cautiously.

  9. Comparison of the Physical and Chemical Properties of Laboratory and Field-Aged Biochars.

    PubMed

    Bakshi, Santanu; Aller, Deborah M; Laird, David A; Chintala, Rajesh

    2016-09-01

    The long-term impact of biochar on soil properties and agronomic outcomes is influenced by changes in the physical and chemical properties of biochars that occur with time (aging) in soil environments. Fresh biochars, however, are often used in studies because aged biochars are generally unavailable. Therefore, a need exists to develop a method for rapid aging of biochars in the laboratory. The objectives of this study were to compare the physicochemical properties of fresh, laboratory-aged (LA), and field-aged (FA) (≥3 yr) biochars and to assess the appropriateness of a laboratory aging procedure that combines acidification, oxidation, and incubations as a mimic to field aging in neutral or acidic soil environments. Twenty-two biochars produced by fast and slow pyrolysis, and gasification techniques from five different biomass feedstocks (hardwood, corn stover, soybean stover, macadamia nut shells, and switchgrass) were studied. In general, both laboratory and field aging caused similar increases in ash-free volatile matter (% w/w), cation and anion exchange capacities, specific surface area, and modifications in oxygen-containing surface functional groups of the biochars. However, ash content increased for FA (18-195%) and decreased for LA (22-74%) biochars, and pH decreased to a greater extent for LA (2.8-6.7 units) than for FA (1.6-3.8 units) biochars. The results demonstrate that the proposed laboratory aging procedure is effective for predicting the direction of changes in biochar properties on field aging. However, in the future we recommend using a less aggressive acid treatment. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  10. [Computer games in childhood and adolescence: relations to addictive behavior, ADHD, and aggression].

    PubMed

    Frölich, Jan; Lehmkuhl, Gerd; Döpfner, Manfred

    2009-09-01

    Playing computer games has become one of the main leisure activities in children and adolescents and increasingly replaces traditional playing and interactional activities. There might exist developmental benefits or positive effects of computer games that can be used for educational or therapeutic purposes. More important several studies have well demonstrated that excessive computer game playing is associated with behavior that features all components of non-chemical addiction and the prevalences across all age groups seem to be impressingly high. This overview relies on a Medline research. Its objective is to describe motivational and developmental characteristics attributed to computer games as well as the prevalences of computer playing in children and adolescents to better understand the risks for addictive use. We especially focus on the relations of excessive computer playing with attention-deficit hyperactivity disorder (ADHD) and aggressive behavior. The results demonstrate that children with ADHD are especially vulnerable to addictive use of computer games due to their neuropsychological profile. Moreover excessive violent computer game playing might be a significant risk variable for aggressive behavior in the presence of personality traits with aggressive cognitions and behavior scripts in the consumers. The increasing clinical meaning of addictive computer games playing urgently necessitates the development of diagnostic and therapeutic tools for clinical practice as well as the cooperation with allied disciplines.

  11. Invited: Advances Toward Practical Detection of Trace Chemical Hazards with Solid State Microarray Devices

    NASA Astrophysics Data System (ADS)

    Raman, Barani; Meier, Douglas; Shenoy, Rupa; Benkstein, Kurt; Semancik, Steve

    2011-09-01

    We describe progress on an array-based microsensor approach employed for detecting trace levels of toxic industrial chemicals (TICs) in air-based backgrounds with varied levels of humidity, and with occasional introduction of aggressive interferents. Our MEMS microhotplate arrays are populated with multiple chemiresistive sensing materials, and all elements are programmed to go through extensive temperature cycling over repetitive cycles with lengths of approximately 20 s. Under such operation, analytically-rich data streams are produced containing the required information for target recognition.

  12. UHPC and NSFRC in Severe Environmental Conditions

    NASA Astrophysics Data System (ADS)

    Rehacek, S.; Citek, D.; Kolisko, J.

    2017-10-01

    Structure and properties of cement composite are time-varying characteristics, depending among others on environmental conditions. The key idea is a struggle for complex research of joint effect of physical, chemical and dynamic loads on the internal structure of cement composite and understanding the correlation between changes in microstructure and macro-scale properties. During the experimental program, specimens will be exposed to combined influence of freeze-thaw cycles, aggressive chemical agents and dynamic loading. The aim is to create a theoretical basis for design of effective cement composites meant to be used in severe environmental conditions.

  13. Reliability and validity of aggressive driving measures in China.

    PubMed

    Li, Fengzhi; Li, Changji; Long, Yunfang; Zhan, Chenglie; Hennessy, Dwight

    2004-12-01

    The present research was designed to examine the psychometric properties of Chinese versions of the Self Report Driver Behavior Aggression and Assertiveness subscales, the Driving Vengeance Questionnaire, and the Violent Driving Questionnaire. Study 1 found that the all scales demonstrated good internal consistency, with alphas ranging from .76 to .87 and that assertive driving was related to demerit points received over the past 12 months while driver aggression and violence were linked to collisions over the past 12 months. Study 2 found that the scales exhibited reasonable test-retest reliability, with correlations ranging from .82 to .89. Finally, Study 3 showed that each scale was predicted by other dangerous driving attitudes and behaviors, similar to the original versions. The consistency between the translated and original scales, the implications for use in a Chinese sample, and the uniformity of actions in the traffic environment across cultures are discussed.

  14. BIOVENTING DEVELOPMENT PROGRAM (TREATMENT AND DESTRUCTION BRANCH, LRPCD, NRMRL)

    EPA Science Inventory

    In a continuing effort to develop environment-friendly and cost-effective remediation technologies, the Land Remediation and Pollution Control Division (LRPCD) conducts an aggressive research and development program in bioventing. LRPCD's bioventing program is multi-faceted, with...

  15. Theoretical and practical aspects of improving the durability of steel reinforcement in transport designs, using passivation and plasticizing chemical additives

    NASA Astrophysics Data System (ADS)

    Velichko, Evgenij; Talipov, Linar

    2017-10-01

    The article deals with the problem of steel reinforcement corrosion in reinforced concrete structures exposed to aggressive media, in particular in reinforced concrete construction of transport infrastructure, in snowy areas, and subject to the influence of chlorides contained in applied deicing agents. Basic schemes for preventing the reinforcement corrosion in reinforced-concrete structures have been considered and analyzed. Prospects of primary protection against corrosion of reinforcement by introducing chemical additives with plasticizing/passivating action in a concrete mixture with mixing water have been considered in detail. The physical/chemical mechanism of the protective action of a superplasticizer together with a passivator has been highlighted.

  16. The effects on student health of interventions modifying the school environment: systematic review.

    PubMed

    Bonell, C; Wells, H; Harden, A; Jamal, F; Fletcher, A; Thomas, J; Campbell, R; Petticrew, M; Whitehead, M; Murphy, S; Moore, L

    2013-08-01

    Owing to the limited effectiveness of traditional health education curricula in schools, there is increasing interest in interventions aiming to promote young people's health by modifying the school environment. Existing systematic reviews cannot determine whether environmental intervention is effective because they examine interventions combining environmental modifications and traditional health education. This gap is significant because school-environment interventions are complex to implement and may be sidelined in underfunded and attainment-focused school systems without evidence to support such an approach. This systematic review examined the effectiveness of school-environment interventions without health-education components on student health and inequalities. This was a systematic review of experimental/quasi-experimental studies of school-environment interventions. Sixteen databases were searched, eliciting 62 329 references which were screened, with included studies quality assessed, data extracted and narratively synthesised. Sixteen reports of 10 studies were included, all from the USA and the UK. Five evaluations of interventions aiming to develop a stronger sense of community and/or improve relationships between staff and students suggested potential benefits particularly regarding violence and aggression. Two trials of interventions enabling students to advocate for changes in school catering and physical activity reported benefits for physical activity but not diet. Three evaluations of improvements to school playgrounds offered weak evidence of effects on physical activity. School environment interventions show the potential to improve young people's health particularly regarding violence, aggression and physical activity. Further trials are required to provide a stronger and more generalisable evidence base.

  17. Plasmon-driven sequential chemical reactions in an aqueous environment.

    PubMed

    Zhang, Xin; Wang, Peijie; Zhang, Zhenglong; Fang, Yurui; Sun, Mengtao

    2014-06-24

    Plasmon-driven sequential chemical reactions were successfully realized in an aqueous environment. In an electrochemical environment, sequential chemical reactions were driven by an applied potential and laser irradiation. Furthermore, the rate of the chemical reaction was controlled via pH, which provides indirect evidence that the hot electrons generated from plasmon decay play an important role in plasmon-driven chemical reactions. In acidic conditions, the hot electrons were captured by the abundant H(+) in the aqueous environment, which prevented the chemical reaction. The developed plasmon-driven chemical reactions in an aqueous environment will significantly expand the applications of plasmon chemistry and may provide a promising avenue for green chemistry using plasmon catalysis in aqueous environments under irradiation by sunlight.

  18. Plasmon-driven sequential chemical reactions in an aqueous environment

    PubMed Central

    Zhang, Xin; Wang, Peijie; Zhang, Zhenglong; Fang, Yurui; Sun, Mengtao

    2014-01-01

    Plasmon-driven sequential chemical reactions were successfully realized in an aqueous environment. In an electrochemical environment, sequential chemical reactions were driven by an applied potential and laser irradiation. Furthermore, the rate of the chemical reaction was controlled via pH, which provides indirect evidence that the hot electrons generated from plasmon decay play an important role in plasmon-driven chemical reactions. In acidic conditions, the hot electrons were captured by the abundant H+ in the aqueous environment, which prevented the chemical reaction. The developed plasmon-driven chemical reactions in an aqueous environment will significantly expand the applications of plasmon chemistry and may provide a promising avenue for green chemistry using plasmon catalysis in aqueous environments under irradiation by sunlight. PMID:24958029

  19. The Significance of Family, Environment, and College Preparation: A Study of Factors Influencing Graduation and Persistence Rates of African American Males Playing Division I Basketball

    ERIC Educational Resources Information Center

    Mitchell, Enzley, IV

    2017-01-01

    The purpose of this study was to identify specific external factors including family composition, pre-college environment, and college preparation that contribute to why some African American males playing basketball at the NCAA Division I level graduate and persist while others do not. Despite an aggressive advertising campaign from the NCAA…

  20. Protective Role of Parenting Attitude on the Behavioral and Neurocognitive Development of the Children from Economically Disadvantaged Families.

    PubMed

    Jung, Da-Eun; Bhang, Soo-Young; Lee, Won-Hye; Yoon, Hae-Joo; Jung, Hee-Yeon; Kim, Yeni

    2018-06-01

    Association between home environment and the behavioral and neurocognitive development of children from a community childcare center for low-income families was examined (aged 6 to 12 years, n=155). The parents performed a questionnaire on home environment (K-HOME-Q) to assess home environment including parenting attitude and the Child Behavior Checklist (K-CBCL). The children performed the Wechsler Intelligence (IQ) Scale, Stroop interference test (Stroop), word fluency test (WF), and design fluency test (DF) to assess their neurocognitive development. 'Nurturing of Development' and 'Variety of Language Interaction' scores from the K-HOME-Q, were inversely associated with total behavior problems, externalization, rule-breaking, and aggressive behavior subscales of K-CBCL, and 'Emotional atmosphere' and 'Tolerance toward the child' scores showed inverse associations with the total behavior problems, rule-breaking, aggressive behavior, and withdrawn/depressed subscales. Despite economic hardship, the mean scores of the neurocognitive tests were comparable to the average level of Korean children's normative sample. However, 'Nurturing of Development' and 'Tolerance toward the Child' score of K-HOME-Q were associated with better executive function (IQ, WF, DF). These results suggest that parental stimulation of development and tolerant parenting attitude may offer protection against the negative effects of suboptimal economic environment on children's behavior and neurocognitive development.

  1. Observer Ratings of Interpersonal Behavior as Predictors of Aggression and Self-Harm in a High-Security Sample of Male Forensic Inpatients.

    PubMed

    Vernham, Zarah; Tapp, James; Moore, Estelle

    2016-05-01

    Incidents of aggression and self-harm in forensic mental health inpatient settings present a significant challenge to practitioners in terms of safely managing and reducing the harm they cause. Research has been conducted to explore the possible predictors of these incidents and has identified a range of environmental, situational, and individual risk factors. However, despite the often interpersonal nature of the majority of aggressive incidents, few studies have investigated forensic inpatient interpersonal styles as predictors of aggression and even fewer have explored the potential interpersonal function of self-harming behaviors. The current study investigated the predictive validity of the Chart of Interpersonal Reactions in Closed Living Environments (CIRCLE) for incidents of verbal and physical aggression, and self-harm recorded from 204 high-secure forensic inpatients. Means comparisons, correlations, and receiver operating characteristics (ROC) were conducted on recorded incident data at 12, 24, and 48 months following baseline assessment using the CIRCLE. Dominant and coercive interpersonal styles were significant predictors of aggression, and a coercive interpersonal style was a significant predictor of self-harm, over the recorded time periods. When categorizing the inpatients on the basis of short- and long-term admissions, these findings were only replicated for inpatients with shorter lengths of stay. The findings support previous research which has demonstrated the benefits of assessing interpersonal style for the purposes of risk planning and management of forensic inpatients. The predictive value may be time-limited in terms of stage of admission. © The Author(s) 2015.

  2. Toward a defense-dominated world

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

    Wood, L.

    1993-08-01

    Maintaining the large-scale peace in a defense-dominated world necessarily will require not only passive but also active defenses against large-scale aggression that are technically feasible, practical and easy to employ -- and robust against perversion into support of aggression. Such peace maintenance tool-sets will feature means for effectively rebuking aggression as well as providing timely and very widely available seaming of aggression underway anywhere. This report discusses the technology base which currently exists to provide world-wide, high-quality imagery at moderate (5--10 meter) spatial resolution or imagery of 1% of the Earth`s land surface at high ({le} 1 meter) resolution nomore » less frequently than daily, at a total cost of the order of $1 B, with operational capability in the later `90s. Such systems could provide timely warning of aggressive actions anywhere. Similarly, space-based means of defeating aggression conducted with even quite short-range ballistic missiles anywhere in the world could be brought into existence by the end of the `90s for a total cost of about $10 B, and small high-altitude, long flight-duration robotic aircraft carrying high-performance sensors and interceptor missilery could provide both seaming and active defenses against attacks conducted with very short range ballistic missiles, as well as attacks launched with air-breathing threats such as bombers and cruise missiles, for a cost per defended area of the order of $10/km{sup 2}. It appears that all of the associated sensors can find apt dual-use as high-performance systems for monitoring physical aspects of the human environment.« less

  3. The interplay between trauma, substance abuse and appetitive aggression and its relation to criminal activity among high-risk males in South Africa.

    PubMed

    Sommer, Jessica; Hinsberger, Martina; Elbert, Thomas; Holtzhausen, Leon; Kaminer, Debra; Seedat, Soraya; Madikane, Solomon; Weierstall, Roland

    2017-01-01

    In persistently unsafe environments, the cumulative exposure to violence predicts not only the development of posttraumatic stress disorder (PTSD), but also of increased aggression and violent outbursts. Substance use disorders interact with these developments, as drug consumption may blunt symptoms and also reduce the threshold for violent acts. Investigating the interplay between these variables and the possible cumulative effect of drug abuse on the attraction to cruelty is a crucial step in understanding the cycle of violence and developing intervention programs that address this cycle in violence-troubled communities such as low-income urban areas in South Africa. Young males at risk (N=290) were recruited through a reintegration center for offenders in Cape Town. We assessed types of traumatic events experienced, PTSD symptom severity, appetitive aggression, committed offenses and patterns of drug abuse prior to the perpetration of violence. Path-analyses confirmed a positive relationship between exposure to traumatic events and PTSD symptom severity, appetitive aggression, the number of committed offenses and drug abuse prior to violence. PTSD symptoms were positively associated with the propensity toward aggression. Furthermore, more severe drug abuse was related to higher attraction to violence and more committed offenses. We conclude that like exposure to violence, drug abuse may play a key role in the attraction to aggression and criminal acts. Measures of violence prevention and psychotherapeutic interventions for trauma-related suffering may not be effective without enduring drug abuse rehabilitation. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  4. Corporal Punishment and Child Aggression: Ethnic-Level Family Cohesion as a Moderator.

    PubMed

    Lee, Yoona; Watson, Malcolm W

    2017-04-01

    Ethnicity has been examined as a putative moderator between parents' use of corporal punishment and children's externalizing behaviors. Yet, the reasons for this potential ethnic-level moderator have not been fully examined. The primary objective of this study was to examine whether the effect of corporal punishment on aggression is ethnic-specific using major racial groups inside and outside the U.S. samples and how the mean levels of cohesion in family relationships as found in different ethnic groups moderate the association between mothers' use of corporal punishment and children's aggression. A total of 729 mothers who had children aged 7 to 13 years were sampled from five ethnic groups (i.e., European American, African American, Hispanic American, Korean, and Chinese). Several hypotheses were tested to examine the moderating effect of ethnic-level, family cohesion on the relation of corporal punishment to children's aggression. As expected, the mean level of family cohesion was significantly different across ethnicities. Consistent results across parallel multilevel and fixed effect models showed that high corporal punishment was associated with more aggression in all ethnicities, but there was a significant variation in the association across ethnicities, and the variation was explained by ethnic-level family cohesion. There were weaker associations between corporal punishment and child aggression among ethnic groups with high family cohesion and stronger associations among ethnic groups with low family cohesion. Ethnic/cultural variation in this study emphasizes the importance of understanding family environment of diverse ethnic groups when evaluating the influence of corporal punishment on child behavior in different ethnic/cultural contexts.

  5. Adolescents' Perceptions of Popularity-Motivated Behaviors, Characteristics, and Relationships in Cyberspace and Cyber Aggression: The Role of Gender.

    PubMed

    Wright, Michelle F

    2017-06-01

    Research is increasingly revealing that adolescents utilize electronic technologies to promote and/or maintain their social standing among their peer group. Little is known about whether adolescents' perceptions of popularity-motivated behaviors, characteristics, and relationships in cyberspace are associated with popularity-motivated cyber relational aggression. It is also unclear how gender might impact these associations, especially considering that adolescent girls and boys differ in regard to the type of behaviors, characteristics, and relationships they believe contribute to popularity. To this end, this study examined the potential moderating effect of gender on the association between adolescents' perceptions of popularity-motivated behaviors, characteristics, and relationships in cyberspace and their engagement in popularity-motivated cyber relational aggression over 1 year, from seventh to eighth grade. There were 217 eighth graders (51 percent female; M age = 12.13) from three middle schools in a large Midwestern city in the United States included in this research. They completed questionnaires on their popularity-motivated behaviors, characteristics, and relationships in cyberspace and their perpetration of popularity-motivated cyber relational aggression during the seventh grade. One year later, they completed the perpetration of popularity-motivated cyber relational aggression questionnaire. The results revealed that the association between popularity-motivated behaviors, characteristics, and relationships in cyberspace and the perpetration of popularity-motivated cyber relational aggression was stronger for girls, while such an association was not found for boys. These findings indicate the importance of considering cyberspace as an environment in which adolescents can enhance their social standing among peers from their school.

  6. Male urine signals social rank in the Mozambique tilapia (Oreochromis mossambicus)

    PubMed Central

    Barata, Eduardo N; Hubbard, Peter C; Almeida, Olinda G; Miranda, António; Canário, Adelino VM

    2007-01-01

    Background The urine of freshwater fish species investigated so far acts as a vehicle for reproductive pheromones affecting the behaviour and physiology of the opposite sex. However, the role of urinary pheromones in intra-sexual competition has received less attention. This is particularly relevant in lek-breeding species, such as the Mozambique tilapia (Oreochromis mossambicus), where males establish dominance hierarchies and there is the possibility for chemical communication in the modulation of aggression among males. To investigate whether males use urine during aggressive interactions, we measured urination frequency of dye-injected males during paired interactions between size-matched males. Furthermore, we assessed urinary volume stored in the bladder of males in a stable social hierarchy and the olfactory potency of their urine by recording of the electro-olfactogram. Results Males released urine in pulses of short duration (about one second) and markedly increased urination frequency during aggressive behaviour, but did not release urine whilst submissive. In the stable hierarchy, subordinate males stored less urine than males of higher social rank; the olfactory potency of the urine was positively correlated with the rank of the male donor. Conclusion Dominant males store urine and use it as a vehicle for odorants actively released during aggressive disputes. The olfactory potency of the urine is positively correlated with the social status of the male. We suggest that males actively advertise their dominant status through urinary odorants which may act as a 'dominance' pheromone to modulate aggression in rivals, thereby contributing to social stability within the lek. PMID:18076759

  7. Initiating change locally in bullying and aggression through the school environment (INCLUSIVE): study protocol for a cluster randomised controlled trial.

    PubMed

    Bonell, Chris; Allen, Elizabeth; Christie, Deborah; Elbourne, Diana; Fletcher, Adam; Grieve, Richard; LeGood, Rosa; Mathiot, Anne; Scott, Stephen; Wiggins, Meg; Viner, Russell M

    2014-09-30

    Systematic reviews suggest that interventions that address school organisation are effective in reducing victimisation and bullying. We successfully piloted a school environment intervention modified from international studies to incorporate 'restorative justice' approaches. This trial aims to establish the effectiveness and cost-effectiveness of the INCLUSIVE intervention in reducing aggression and bullying in English secondary schools. cluster randomised trial. 40 state-supported secondary schools. OUTCOMES assessed among the cohort of students in year 8 (n = approximately 6,000) in intervention year 1. INCLUSIVE is a school-led intervention which combines changes to the school environment with the promotion of social and emotional skills and restorative practices through: the formation of a school action group involving students and staff supported by an external facilitator to review local data on needs, determine priorities, and develop and implement an action plan for revising relevant school policies/rules and other actions to improve relationships at school and reduce aggression; staff training in restorative practices; and a new social and emotional skills curriculum. The intervention will be delivered by schools supported in the first two years by educational facilitators independent of the research team, with a third locally facilitated intervention year.Comparator: normal practice. primary: 2 primary outcomes at student level assessed at baseline and at 36 months:1. Aggressive behaviours in school: Edinburgh Study of Youth Transitions and Crime school misbehaviour subscale (ESYTC)2. Bullying and victimisation: Gatehouse Bullying Scale (GBS)Secondary outcomes assessed at baseline, 24 and 36 months will include measures relating to the economic evaluation, psychosocial outcomes in students and staff and school-level truancy and exclusion rates. 20 schools per arm will provide 90% power to identify an effect size of 0.25 SD with a 5% significance level.Randomisation: eligible consenting schools will be randomised stratified for single sex versus mixed sex schools, school-level deprivation and measures of school attainment. The trial will be run by independent research and intervention teams and supervised by a Trial Steering Committee and a Data Monitoring Committee (DMC). Current Controlled Trials ISRCTN10751359 (Registered 11 March 2014).

  8. Analysis of rare earth elements in coal fly ash using laser ablation inductively coupled plasma mass spectrometry and scanning electron microscopy

    NASA Astrophysics Data System (ADS)

    Thompson, Robert L.; Bank, Tracy; Montross, Scott; Roth, Elliot; Howard, Bret; Verba, Circe; Granite, Evan

    2018-05-01

    Reference standard NIST SRM 1633b and FA 345, a fly ash sample from an eastern U.S. coal power plant, were analyzed to determine and quantify the mineralogical association of rare earth elements (REE). These analyses were completed using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) and a scanning electron microscope, equipped with an energy-dispersive X-ray spectrometer (SEM-EDS). Internal standardization was avoided by quantifying elemental concentrations by normalizing to 100% oxides. Mineral grains containing elevated REE concentrations were found in diverse chemical environments, but were most commonly found in regions where Al and Si were predominant. Dividing the spot analyses into time segments yielded plots that showed the REE content changing over time as individual mineral grains were being ablated. SEM-EDS images of FA 345 confirmed the trends that were found in the LA-ICP-MS results. Small grains of apatite, monazite, or zircon were frequently observed as free mineral grains or embedded in amorphous aluminosilicate glass and were not associated with ferrous particles. This finding is consistent with previous reports that magnetic enrichment may be an effective way of concentrating non-magnetic REE phases. Furthermore, aggressive mechanical and chemical-based separation schemes will be required to separate and recover REE from aluminosilicate glass.

  9. Enhancing the aggressive intensity of hydrodynamic cavitation through a Venturi tube by increasing the pressure in the region where the bubbles collapse

    NASA Astrophysics Data System (ADS)

    Soyama, H.; Hoshino, J.

    2016-04-01

    In this paper, we used a Venturi tube for generating hydrodynamic cavitation, and in order to obtain the optimum conditions for this to be used in chemical processes, the relationship between the aggressive intensity of the cavitation and the downstream pressure where the cavitation bubbles collapse was investigated. The acoustic power and the luminescence induced by the bubbles collapsing were investigated under various cavitating conditions, and the relationships between these and the cavitation number, which depends on the upstream pressure, the downstream pressure at the throat of the tube and the vapor pressure of the test water, was found. It was shown that the optimum downstream pressure, i.e., the pressure in the region where the bubbles collapse, increased the aggressive intensity by a factor of about 100 compared to atmospheric pressure without the need to increase the input power. Although the optimum downstream pressure varied with the upstream pressure, the cavitation number giving the optimum conditions was constant for all upstream pressures.

  10. Neuromodulation of Nestmate Recognition Decisions by Pavement Ants.

    PubMed

    Bubak, Andrew N; Yaeger, Jazmine D W; Renner, Kenneth J; Swallow, John G; Greene, Michael J

    2016-01-01

    Ant colonies are distributed systems that are regulated in a non-hierarchical manner. Without a central authority, individuals inform their decisions by comparing information in local cues to a set of inherent behavioral rules. Individual behavioral decisions collectively change colony behavior and lead to self-organization capable of solving complex problems such as the decision to engage in aggressive societal conflicts with neighbors. Despite the relevance to colony fitness, the mechanisms that drive individual decisions leading to cooperative behavior are not well understood. Here we show how sensory information, both tactile and chemical, and social context-isolation, nestmate interaction, or fighting non-nestmates-affects brain monoamine levels in pavement ants (Tetramorium caespitum). Our results provide evidence that changes in octopamine and serotonin in the brains of individuals are sufficient to alter the decision by pavement ants to be aggressive towards non-nestmate ants whereas increased brain levels of dopamine correlate to physical fighting. We propose a model in which the changes in brain states of many workers collectively lead to the self-organization of societal aggression between neighboring colonies of pavement ants.

  11. Neuromodulation of Nestmate Recognition Decisions by Pavement Ants

    PubMed Central

    Bubak, Andrew N.; Yaeger, Jazmine D. W.; Renner, Kenneth J.; Swallow, John G.; Greene, Michael J.

    2016-01-01

    Ant colonies are distributed systems that are regulated in a non-hierarchical manner. Without a central authority, individuals inform their decisions by comparing information in local cues to a set of inherent behavioral rules. Individual behavioral decisions collectively change colony behavior and lead to self-organization capable of solving complex problems such as the decision to engage in aggressive societal conflicts with neighbors. Despite the relevance to colony fitness, the mechanisms that drive individual decisions leading to cooperative behavior are not well understood. Here we show how sensory information, both tactile and chemical, and social context—isolation, nestmate interaction, or fighting non-nestmates—affects brain monoamine levels in pavement ants (Tetramorium caespitum). Our results provide evidence that changes in octopamine and serotonin in the brains of individuals are sufficient to alter the decision by pavement ants to be aggressive towards non-nestmate ants whereas increased brain levels of dopamine correlate to physical fighting. We propose a model in which the changes in brain states of many workers collectively lead to the self-organization of societal aggression between neighboring colonies of pavement ants. PMID:27846261

  12. Stress Training and the New Military Environment

    DTIC Science & Technology

    2006-04-01

    stressors in military missions may be for example, fatigue and boredom . A typical acute stressor is threat. The outcomes of stress can be either... prosocial behaviour, increased personal aggression, neglect of social or interpersonal cues, and less cooperative behaviour among team members [6

  13. Strain corrosion cracking in rpm sewer piping

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

    Hopkins, S.W.; Wachob, H.F.; Duffner, D.H.

    1993-12-31

    Long term, aggressive environmental exposure can result in localized failure of large diameter, glass reinforced plastic mortar (RPM) piping. In order to evaluate the performance of the liner and glass reinforced matrix polyester resin, accelerated strain corrosion tests were performed on samples of RPM piping that had already experienced almost 15 years of service. To assess the sensitivity of RPM pipe to acidic environments and to correlate the fractography of the laboratory produced failures with the excavated crack, short segments of 8-inch and 48-inch diameter piping were statically loaded to produce various known surface strains. After preloading the specimens tomore » fixed strain levels, these samples were then exposed to sulfuric acid solutions having pH values of 2.7 and 4.7 and monitored as a function of time until failure. The resulting lifetimes were related to initial surface strains and showed a decreasing logarithmic relationship. Fractographic examination of the excavated crack revealed the typical strain corrosion fractography of glass fibers after almost a 1000 hour exposure at 1.3 % strain; similar fractographic observations were obtained from failed laboratory samples. At shorter times, failure appeared to be overload in nature and exhibited little, if any, timedependent fracture features. Fractographic examination of the excavated crack strongly indicated that the crack had been present for a significant time. The extremely aggressive environment had totally dissolved the exposed glass reinforcement. Based on the laboratory strain corrosion performance, the nature of the contained cracking, and fractography of the failed surface, cracking of the excavated RPM pipe was believed to be the result of an early overload failure that subsequently propagated slowly via strain corrosion in an extremely aggressive environment.« less

  14. No corrosion of 304 stainless steel implant after 40 years of service.

    PubMed

    Blackwood, D J; Pereira, B P

    2004-07-01

    When exposed to 0.9% NaCl type 304 stainless steel undergoes severe pitting corrosion within a matter of days. However, a Sherman plate fabricated from type 304 stainless steel remained inside a patient's arm for almost 40 years without any visible indications of corrosion. Given the previous understanding of the pathological environments this was considered quite remarkable. It is proposed that the low dissolved oxygen levels found in human-body fluids makes the long-term in vivo environment much more benign than would be anticipated from in vitro experiments. Furthermore, it is proposed that previous cases of localized pitting corrosion on stainless steel implants most likely arose due to the development of short-term aggressive conditions due to pathological changes in the surrounding tissue as a result of the trauma of the implant procedure. In the present case the Sherman plate was sufficiently small that the surrounding tissue was not aggravated sufficiently to lead to the development of such an environment aggressive. The conclusion that surgical implants are at most risk during the first few weeks of service implies that short-term corrosion protection methods, such as coatings, may be more effective than previously thought.

  15. Early intervention reduces morbidity in extravasation injuries from 'lighter fuel' injection.

    PubMed

    Thaha, M A; McKinnell, T H; Graham, K E; Naasan, A N

    2007-01-01

    Injection of 'lighter fuel' with suicidal intent is rare. Extravasation of the chemical may rarely cause systemic toxicity, but usually it results in extensive soft tissue damage. Such injuries when managed by the traditional expectant policy are associated with considerable morbidity. Early aggressive surgical management using 'saline flush out' limits the tissue damage by stopping the natural progression of the chemical mediated injury and the subsequent inflammatory response, thereby allowing better skin preservation and functional outcome in these cases. We report a case of 'lighter fuel' subcutaneous extravasation injury managed by 'saline flush out' technique soon after presentation.

  16. Alterations to embryonic serotonin change aggression and fearfulness

    USDA-ARS?s Scientific Manuscript database

    Prenatal environment, including maternal hormones, affects the development of the serotonin (5-HT) system, with long-lasting effects on mood and behavioral exhibition in children and adults. The chicken provides a unique animal model to study the effects of embryonic development on childhood and ado...

  17. 40 CFR 1066.801 - Applicability and general provisions.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... emission effects from aggressive driving and operation with the vehicle's air conditioner. The SFTP is... driving schedule represents about 3.6 miles of urban driving with the air conditioner operating; and the.... 1066.801 Section 1066.801 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR...

  18. Forensic Suicides and Attempted Suicides.

    ERIC Educational Resources Information Center

    French, Laurence A.

    1986-01-01

    Forensic suicides and suicide attempts challenge certain premises long held by classical suicidologists. Chronic ambiguity and free-floating rage, attributes exacerbated by the jail-like environment of many forensic units, pose a situation whereby either the self or others become convenient targets for aggression release. (Author/BL)

  19. Strategic planning unbound.

    PubMed

    Hiam, A

    1993-01-01

    The strategic planner's role has not kept up with the demands of today's complex business environment. But catching up is the planner's responsibility. Become participative, missionary, and aggressively iconoclastic, and you can be a catalyst of positive change. Stay rooted in the past, and you're just an impediment.

  20. Examining School Violence.

    ERIC Educational Resources Information Center

    Rosen, Barry, Ed.; Dobry, Diane, Ed.; Andrews, Heather, Ed.; Reznik, Deidre, Ed.

    2001-01-01

    This document considers school violence by reviewing the school environment, assessing the difficulties and causes of violence, and offering solutions to the problems. One study describes risk factors for aggressive behavior among middle school students and presents steps that can be taken to prevent the development of such behavior. Several…

  1. SSME Investment in Turbomachinery Inducer Impeller Design Tools and Methodology

    NASA Technical Reports Server (NTRS)

    Zoladz, Thomas; Mitchell, William; Lunde, Kevin

    2010-01-01

    Within the rocket engine industry, SSME turbomachines are the de facto standards of success with regard to meeting aggressive performance requirements under challenging operational environments. Over the Shuttle era, SSME has invested heavily in our national inducer impeller design infrastructure. While both low and high pressure turbopump failures/anomaly resolution efforts spurred some of these investments, the SSME program was a major benefactor of key areas of turbomachinery inducer-impeller research outside of flight manifest pressures. Over the past several decades, key turbopump internal environments have been interrogated via highly instrumented hot-fire and cold-flow testing. Likewise, SSME has sponsored the advancement of time accurate and cavitating inducer impeller computation fluid dynamics (CFD) tools. These investments together have led to a better understanding of the complex internal flow fields within aggressive high performing inducers and impellers. New design tools and methodologies have evolved which intend to provide confident blade designs which strike an appropriate balance between performance and self induced load management.

  2. Application of Granulated Blast Furnace Slag in Cement Composites Exposed to Biogenic Acid Attack

    NASA Astrophysics Data System (ADS)

    Kovalcikova, M.; Estokova, A.; Luptakova, A.

    2015-11-01

    The deterioration of cement-based materials used for the civil infrastructure has led to the realization that cement-based materials, such as concrete, must be improved in terms of their properties and durability. Leaching of calcium ions increases the porosity of cement- based materials, consequently resulting in a negative effect on durability since it provides an entry for aggressive harmful ions, causing corrosion of concrete. The use supplementary cementing composite materials have been reported to improve the resistance of concrete to deterioration by aggressive chemicals. The paper is focused on the investigation of the influence of biogenic acid attack on the cement composites affected by bacteria Acidithiobacillus thiooxidans. The concrete specimens with 65 wt. % addition of antimicrobial activated granulated blast furnace slag as durability increasing factor as well as without any addition were studied. The experiments proceeded during 150 days under model laboratory conditions. The pH values and chemical composition of leachates were measured after each 30- day cycle. The calcium and silicon contents in leachates were evaluated using X - ray fluorescence method (XRF). Summarizing the results, the 65% wt. addition of antimicrobial activated granulated blast furnace slag was not confirmed to be more resistant.

  3. Evaluating a cognitive/ecological program for the prevention of aggression among urban children.

    PubMed

    Huesmann, L R; Maxwell, C D; Eron, L; Dahlberg, L L; Guerra, N G; Tolan, P H; VanAcker, R; Henry, D

    1996-01-01

    The Metropolitan Area Child Study (MACS) is a multifaceted school- and family-based intervention and evaluation study designed to prevent and understand the development of aggressive behavior. The multifaceted interventions are grounded in combined social-cognitive and ecologic theories. Social-cognitive theories contend that cognitive scripts, attributions, and beliefs acquired early in life mediate the effects of ecological factors that influence the development of antisocial behavior. Prevention programs aimed at these cognitions must address multiple dimensions of the child's environment including family, peer, school, and community. The program has three levels of intervention delivered in two-year segments: (1) Level 1: a general enhancement classroom intervention that stresses culturally sensitive student and teacher interaction involving instructional and classroom management strategies and a social-cognitive curriculum that mitigates aggressive development; (2) Level 2: intensive small-group sessions designed to change children's cognitions and enhance peer relationship skills for at-risk children added to the general classroom enhancement program; and (3) Level 3: a one-year family relationship intervention that stresses parenting skill building and emotional responsiveness in family interactions added to the general enhancement and small-group training conditions. Sixteen Chicago-area schools are randomly assigned (four each) to a control group or one of the three intervention levels. Individual child assessment, peer assessments, classroom behavioral observations, and archival data are collected before the interventions begin, during the interventions, at the end of each intervention, and at a follow-up point. The pretests indicate that the children on average have higher levels of aggression than found nationally and elevated clinical levels of other psychopathologies. Across the four intervention levels there are no significant differences in ethnic composition, socio-economic status (SES), aggressive behavior, and normative beliefs about aggression.

  4. Effect of septal lesions on male song and aggression in the colonial zebra finch (Taeniopygia guttata) and the territorial field sparrow (Spizella pusilla)

    PubMed

    Goodson, J L; Eibach, R; Sakata, J; Adkins-Regan, E

    1999-01-01

    The present investigation assessed the effect of lesions of the septum on male courtship and aggression in the territorial field sparrow (Spizella pusilla) and the colonial zebra finch (Taeniopygia guttata). In addition, pair-bonding and a variety of other social behaviors were examined in the zebra finch and dawn song (both the strictly agonistic song type and the multipurpose song type) was examined in the field sparrow. Zebra finches were tested in three phases both before and after receiving bilateral electrolytic lesions of the septum or sham surgery. These phases were: (1) competition tests in which a subject and a stimulus male were exposed to a female in an adjacent cage; (2) sexual behavior tests with a female; and (3) 10-day group cage tests in which subjects were in a mixed-sex environment. Aggressive behaviors (chases, threats, beak fences and pecks) were significantly reduced by septal lesions but not by sham surgery. Directed song (courtship) was significantly reduced in sexual behavior tests, with similar trends in other testing phases. Male field sparrows were tested 2 days pre-surgery and 2 days post-surgery in outdoor aviaries placed in their natural habitat. Tests consisted of dawn song observations and observations of courtship and aggression following introduction of a female to the subject's aviary, which was followed 10 min later by the introduction of another male (without removing the female). Septal lesions significantly facilitated both overt aggression (chases) and the number of simple (multi-purpose) songs. These results provide evidence that the septum participates in the regulation of male aggression and song in songbirds, and further suggest that variations in septal function may exist between territorial and colonial species.

  5. Effect of septal lesions on male song and aggression in the colonial zebra finch (Taeniopygia guttata) and the territorial field sparrow (Spizella pusilla)

    PubMed

    Goodson, J L; Eibach, R; Sakata, J; Adkins-Regan, E

    1999-05-01

    The present investigation assessed the effect of lesions of the septum on male courtship and aggression in the territorial field sparrow (Spizella pusilla) and the colonial zebra finch (Taeniopygia guttata). In addition, pair-bonding and a variety of other social behaviors were examined in the zebra finch and dawn song (both the strictly agonistic song type and the multipurpose song type) was examined in the field sparrow. Zebra finches were tested in three phases both before and after receiving bilateral electrolytic lesions of the septum or sham surgery. These phases were: (1) competition tests in which a subject and a stimulus male were exposed to a female in an adjacent cage; (2) sexual behavior tests with a female; and (3) 10-day group cage tests in which subjects were in a mixed-sex environment. Aggressive behaviors (chases, threats, beak fences and pecks) were significantly reduced by septal lesions but not by sham surgery. Directed song (courtship) was significantly reduced in sexual behavior tests, with similar trends in other testing phases. Male field sparrows were tested 2 days pre-surgery and 2 days post-surgery in outdoor aviaries placed in their natural habitat. Tests consisted of dawn song observations and observations of courtship and aggression following introduction of a female to the subject's aviary, which was followed 10 min later by the introduction of another male (without removing the female). Septal lesions significantly facilitated both overt aggression (chases) and the number of simple (multi-purpose) songs. These results provide evidence that the septum participates in the regulation of male aggression and song in songbirds, and further suggest that variations in septal function may exist between territorial and colonial species.

  6. Relations among appetitive aggression, post-traumatic stress and motives for demobilization: a study in former Colombian combatants

    PubMed Central

    2013-01-01

    Background Former combatants have frequently reported that aggressive behaviour can be appetitive and appealing. This appetitive aggression (AA) may be adaptive for survival in a violent environment, as it is associated with a reduced risk of combat-related psychological traumatization. At the same time, AA might impair motivation for re-integration to civil life after ending active duty. Whereas in Colombia those combatants who volunteered for demobilization were mostly tired of fighting, those who demobilized collectively did so mainly by force of the government. We predicted those who were demobilized collectively would still be attracted to violence, and benefit from the resilience against trauma-related mental suffering, moderated by appetitive aggression, as they would have continued fighting had they not been forced to stop. Method A sample of 252 former Colombian former combatants from paramilitary and guerrilla forces was investigated. Appetitive aggression was assessed using the Appetitive Aggression Scale (AAS) and post-traumatic stress disorder (PTSD) symptoms with the PTSD Symptom Scale-Interview (PSS-I). We distinguished between individual and group demobilization and assessed reasons for disarmament. Results Most of the guerrilla troops who demobilized individually and were tired of fighting reported both an attraction to violence as well as increased trauma symptoms, owing to their former engagement in violent behaviour. In contrast, among those who were demobilized collectively, appetitive aggression was associated with a reduced risk of PTSD. However, this effect was not present in those combatants in the upper quartile of PTSD symptom severity. Conclusion The influence of combat experience on traumatization, as well as the motivation for demobilization, differs remarkably between those combatants who demobilized individually and those who were members of a group that was forced to demobilize. This has important implications for the implementation of re-integration programmes and therapeutic interventions. PMID:23575192

  7. Alpha spectroscopy by the Φ25 mm×0.1 mm YAlO3:Ce scintillation detector under atmospheric conditions

    NASA Astrophysics Data System (ADS)

    Kvasnicka, Jiri; Urban, Tomas; Tous, Jan; Smejkal, Jan; Blazek, Karel; Nikl, Martin

    2017-06-01

    The YAlO3:Ce scintillation crystal has excellent mechanical properties and is not affected if used in chemically aggressive environments. The detector with the diameter of Φ25.4 mm and thickness of 0.1 mm was coupled with the PMT, associated electronics and the MCA in order to study its alpha spectroscopy properties. The measured alpha spectra of the surface calibration sources of 241Am and 230Th were compared with results of a Monte Carlo simulation. The experiment and the simulation were carried out for three distances between the detector and the surface alpha source in order to assess the effect of the distance on the detected energy of alpha radiation. Finally, the detector was used for the monitoring of radon (222Rn) decay products (radon daughters) in the air. It was concluded that the detector is suitable for the in-situ alpha spectroscopy monitoring under ambient atmospheric conditions. Nevertheless, in order to identify radionuclides and their activity from the measured alpha spectra a computer code would need to be developed.

  8. Selective deposition of polycrystalline diamond films using photolithography with addition of nanodiamonds as nucleation centers

    NASA Astrophysics Data System (ADS)

    Okhotnikov, V. V.; Linnik, S. A.; Gaidaichuk, A. V.; Shashev, D. V.; Nazarova, G. Yu; Yurchenko, V. I.

    2016-02-01

    A new method of selective deposition of polycrystalline diamond has been developed and studied. The diamond coatings with a complex, predetermined geometry and resolution up to 5 μm were obtained. A high density of polycrystallites in the coating area was reached (up to 32·107 pcs/cm2). The uniformity of the film reached 100%, and the degree of the surface contamination by parasitic crystals did not exceed 2%. The technology was based on the application of the standard photolithography with an addition of nanodiamond suspension into the photoresist that provided the creation of the centers of further nucleation in the areas which require further overgrowth. The films were deposited onto monocrystalline silicon substrates using the method of “hot filaments” in the CVD reactor. The properties of the coating and the impact of the nanodiamond suspension concentration in the photoresist were also studied. The potential use of the given method includes a high resolution, technological efficiency, and low labor costs compared to the standard methods (laser treatment, chemical etching in aggressive environments,).

  9. Reaction of common bean lines and aggressiveness of Sclerotinia sclerotiorum isolates.

    PubMed

    Silva, P H; Santos, J B; Lima, I A; Lara, L A C; Alves, F C

    2014-11-07

    The aims of this study were to evaluate the reaction of common bean lines to white mold, the aggressiveness of different Sclerotinia sclerotiorum isolates from various common bean production areas in Brazil, and comparison of the diallel and GGE (genotype main effect plus genotype-by-environment interaction) biplot analysis procedures via study of the line-by-isolate interaction. Eleven common bean (Phaseolus vulgaris) lines derived from 3 backcross populations were used. Field experiments were performed in the experimental area of the Departamento de Biologia of the Universidade Federal de Lavras, Lavras, MG, Brazil, in the 2011 and 2012 dry crop season and 2011 winter crop season through a randomized block design with 3 replications. This study was also set up in a greenhouse. Inoculations were performed 28 days after sowing by means of the straw test method. The reaction of the bean lines to white mold was assessed according to a diagrammatic scale from 1 (plant without symptoms) to 9 (dead plant). Estimations of general reaction capacity (lines) and general aggressiveness capacity (isolates) indicated different horizontal levels of resistance in the lines and levels of aggressiveness in the isolates. Therefore, it was possible to select more resistant lines and foresee those crosses that are the most promising for increasing the level of resistance. It was also possible to identify the most aggressive isolates that were more efficient in distinguishing the lines. Both diallel and GGE biplot analyses were useful in identifying the genotypic values of lines and isolates.

  10. A pH-Sensing Optode for Mapping Spatiotemporal Gradients in 3D Paper-Based Cell Cultures.

    PubMed

    Kenney, Rachael M; Boyce, Matthew W; Whitman, Nathan A; Kromhout, Brenden P; Lockett, Matthew R

    2018-02-06

    Paper-based cultures are an emerging platform for preparing 3D tissue-like structures. Chemical gradients can be imposed upon these cultures, generating microenvironments similar to those found in poorly vascularized tumors. There is increasing evidence that the tumor microenvironment is responsible for promoting drug resistance and increased invasiveness. Acidosis, or the acidification of the extracellular space, is particularly important in promoting these aggressive cancer phenotypes. To better understand how cells respond to acidosis there is a need for 3D culture platforms that not only model relevant disease states but also contain sensors capable of quantifying small molecules in the extracellular environment. In this work, we describe pH-sensing optodes that are capable of generating high spatial and temporal resolution maps of pH gradients in paper-based cultures. This sensor was fabricated by suspending microparticles containing pH-sensitive (fluorescein) and pH-insensitive (diphenylanthracene) dyes in a polyurethane hydrogel, which was then coated onto a transparent film. The pH-sensing films have a fast response time, are reversible, stable in long-term culture environments, have minimal photobleaching, and are not cytotoxic. These films have a pK a of 7.61 ± 0.04 and are sensitive in the pH range corresponding to normal and tumorigenic tissues. With these optodes, we measured the spatiotemporal evolution of pH gradients in paper-based tumor models.

  11. Temperamental Differences in Children’s Reactions to Peer Victimization

    PubMed Central

    Sugimura, Niwako; Rudolph, Karen D.

    2015-01-01

    Objective This research examined the hypothesis that temperament and sex moderate the contribution of peer victimization to children’s subsequent adjustment (aggression and depressive symptoms). Method Children (125 boys, 158 girls; M age = 7.95 years, SD = 0.32; 77.7% White, 22.3% minority) and teachers reported on overt and relational victimization. Parents rated children’s temperament (inhibitory control and negative emotionality) and depressive symptoms, and teachers reported on children’s overt and relational aggression. Results Across a one-year time period, (a) overt victimization predicted overt aggression in girls with poor inhibitory control; (b) overt and relational victimization predicted depressive symptoms in girls with high negative emotionality; and (c) relational victimization predicted depressive symptoms in boys with low negative emotionality. Conclusions This research helps to explain individual variation in children’s reactions to peer victimization, and has implications for person-by-environment models of development. Moreover, this research informs the development of targeted intervention programs for victimized youth that bolster specific resources depending on their temperament. PMID:22420650

  12. Online Moral Disengagement, Cyberbullying, and Cyber-Aggression.

    PubMed

    Runions, Kevin C; Bak, Michal

    2015-07-01

    The study of moral disengagement has greatly informed research on aggression and bullying. There has been some debate on whether cyberbullies and other cyber-aggressors show more or less of a tendency for moral disengagement than traditional aggressors and bullies. However, according to the triadic model of reciprocal determinism, an individual's behavior influences and is influenced by both personal factors and his/her social environment. This article reviews the literature to propose a new conceptual framework addressing how features of the online context may enable specific mechanisms that facilitate moral disengagement. Specific affordances for moral disengagement proposed here include the paucity of social-emotional cues, the ease of disseminating communication via social networks, and the media attention on cyberbullying, which may elicit moral justification, euphemistic labeling, palliative comparison, diffusion and displacement of responsibility, minimizing and disregarding the consequences for others, dehumanization, and attribution of blame. These ideas suggest that by providing affordances for these mechanisms of moral disengagement, online settings may facilitate cyber-aggression and cyberbullying.

  13. Experimental Studies on Hypersonic Stagnation Point Chemical Environment

    DTIC Science & Technology

    2006-02-01

    conditions [60]. Having this complete definition we will focus on the chemical environment produce in the SPR. 3.2 Chemical environment evaluation Flow ... chemistry involves a very large number of processes and microscopic phenomena, they are usually summarized in a set of chemical reactions, with their own

  14. Assessment of Resistance of Bacillus Horneckiae Endospores to UV Radiation and Function of Their Extraneous Layer in Resistance

    NASA Technical Reports Server (NTRS)

    Zachariah, Malcolm M.; Vaishampayan, Parag

    2011-01-01

    Spore-forming microbes are highly resistant to various physical and chemical conditions, which include ionizing and UV radiation, desiccation and oxidative stress, and the harsh environment of outer space or planetary surfaces. The spore's resistance might be due to their metabolically dormant state, and/or by the presence of a series of protective structures that encase the interior-most compartment, the core, which houses the spore chromosome. These spores have multiple layers surrounding the cell that are not found in vegetative cells, and some species have an outer layer of proteins and glycoproteins termed the "exosporium" or a fibrous "extraneous layer" (EL). Bacillus horneckiae is an EL-producing novel sporeformer isolated from a Phoenix spacecraft assembly clean room, and it has previously demonstrated resistance to UV radiation up to 1000 J/m(sup 2). The EL appears to bind B. horneckiae spores into large aggregations, or biofilms, and may confer some UV resistance to the spores. Multiple culturing and purification schemes were tried to achieve high purity spores because vegetative cells would skew UV resistance results. An ethanol-based purification scheme produced high purity spores. Selective removal of the EL from spores was attempted with two schemes: a chemical extraction method and physical extraction (sonication). Results from survival rates in the presence and absence of the external layer will provide a new understanding of the role of biofilms and passive resistance that may favor survival of biological systems in aggressive extra-terrestrial environments. The chemical extraction method decreased viable counts of spores and lead to an inconclusive change UV resistance relative to non-extracted spores. The physical extraction method lead to non-aggregated spores and did not alter viability; however, it produced UV resistance profiles similar to non-extracted spores. In addition to the EL-removal study, samples of B. horneckiae spores dried on aluminum coupons and exposed to increasing UV (200-400 nm range) levels (0 to 8.0 x 105 kJ/m(sup 2)) were tested for viability, which indicated that the maximum UV exposure level that still resulted in viable spores was 5.0 x 10? kJ/m(sup 2).

  15. Mimicking natural systems: Changes in behavior as a result of dynamic exposure to naproxen.

    PubMed

    Neal, Alexandra E; Moore, Paul A

    2017-01-01

    Animals living in aquatic habitats regularly encounter anthropogenic chemical pollution. Typically, the toxicity of a chemical toxicant is determined by the median lethal concentration (LC 50 ) through a static exposure test. However, LC 50 values and static tests do not provide an accurate representation of exposure to pollutants within natural stream systems. In their native habitats, animals experience exposure as a fluctuating concentration due to turbulent mixing, temporal variations of contamination (seasonal inputs), and contaminant input type (point vs. non-point). Research has shown that turbulent environments produce exposures with a high degree of fluctuation in frequency, duration, and intensity. In order to more effectively evaluate the effects of pollutants, we created a dynamic exposure paradigm, utilizing both flow and substrate within a small mesocosm. A commonly used pharmaceutical, naproxen, was used as the toxicant and female crayfish (Orconectes virilis) as the target organism to investigate changes in fighting behavior as a result of dynamic exposure. Crayfish underwent either a 23h long static or a dynamic exposure to naproxen. Following exposure, the target crayfish and an unexposed size matched opponent underwent a 15min fight trial. These fight trials were recorded and later analyzed using a standard ethogram. Results indicate that exposure to sublethal concentrations of naproxen, in both static and flowing conditions, negatively impact aggressive behavior. Results also indicate that a dynamic exposure paradigm has a greater negative impact on behavior than a static exposure. Turbulence and habitat structure play important roles in shaping chemical exposure. Future research should incorporate features of dynamic chemical exposure in order to form a more comprehensive image of chemical exposure and predict the resulting sublethal effects from exposure. Possible techniques for assessment include utilizing flow-through experimental set-ups in tandem with behavioral or physiological endpoints as opposed to acute toxicity. Other possibilities of assessment could involve utilizing fine-scale chemical measurements of pollutants to determine the actual concentrations animals encounter during an exposure event. Copyright © 2016 Elsevier Inc. All rights reserved.

  16. Educations in Ethnic Violence: Identity, Educational Bubbles, and Resource Mobilization

    ERIC Educational Resources Information Center

    Lange, Matthew

    2011-01-01

    In "Educations in Ethnic Violence", Matthew Lange explores the effects education has on ethnic violence. Lange contradicts the widely-held belief that education promotes peace and tolerance. Rather, Lange finds that education commonly contributes to aggression, especially in environments with ethnic divisions, limited resources, and…

  17. Creating Inclusive School Environments: Recommendations for the Management of Neurobehavioural Comorbidities in Children with Epilepsy

    ERIC Educational Resources Information Center

    MacKinnon, Cheryl; Roberts, Jillian; Wylie, Jaimie

    2016-01-01

    The neurobehavioural comorbidities associated with childhood epilepsy present significant physical challenges (i.e., excessive fatigue, memory impairment, headaches, visual impairments), emotional challenges (i.e., depression, anxiety), behavioural challenges (i.e., inattentiveness, distractibility, aggression), and social challenges (i.e., peer…

  18. Media Violence and Children.

    ERIC Educational Resources Information Center

    Groebel, Jo

    1998-01-01

    Presents the results of the UNESCO global study on media violence and children which was conducted between 1996 and 1997. Highlights include the role of the media, media heroes as role models, media violence and aggression, differences by gender, rural versus urban environments, the pervasiveness of television, and recommendations. (Author/LRW)

  19. Investigation of anticorrosion properties of nanocomposites of spray coated zinc oxide and titanium dioxide thin films on stainless steel (304L SS) in saline environment

    NASA Astrophysics Data System (ADS)

    P, Muhamed Shajudheen V.; S, Saravana Kumar; V, Senthil Kumar; Maheswari A, Uma; M, Sivakumar; Rani K, Anitha

    2018-01-01

    The present study reports the anticorrosive nature of nanocomposite thin films of zinc oxide and titanium dioxide on steel substrate (304L SS) using spray coating method. The morphology and chemical constituents of the nanocomposite thin film were characterized by field effect scanning electron microscopy and energy dispersive analysis of x-ray (EDAX) studies. From the EDAX studies, it was observed that nanocomposite coatings of desired stoichiometry can be synthesized using present coating technique. The cyclic voltametric techniques such as Tafel analysis and electrochemical impedance spectroscopy (EIS) analysis were conducted to study the anticorrosion properties of the coatings. The E corr values obtained from Tafel polarization curves of the sample coated with nanocomposites of ZnO and TiO2 in different ratios (5:1, 1:1 and 1:5) indicated that the corrosion resistance was improved compared to bare steel. The coating resistance values obtained from the Nyquist plot after fitting with equivalent circuit confirmed the improved anticorrosion performance of the coated samples. The sample coated with ZnO: TiO2 in the ratio 1:5 showed better corrosion resistance compared to other ratios. The Tafel and EIS studies were repeated after exposure to 5% NaCl for 390 h and the results indicated the anticorrosive nature of the coating in the aggressive environment. The root mean square deviation of surface roughness values calculated from the AFM images before and after salt spray indicated the stability of coating in the saline environment.

  20. Behavior of steelhead fry in a laboratory stream is affected by fish density but not rearing environment

    USGS Publications Warehouse

    Riley, Stephen C.; Tatara, Christopher P.; Berejikian, Barry A.; Flagg, Thomas A.

    2009-01-01

    We quantified the aggression, feeding, dominance, position choice, and territory size of naturally reared steelhead Oncorhynchus mykiss fry stocked with two types of hatchery-reared fry (from conventional and enriched rearing environments) at two densities in experimental flumes to determine how rearing environment and fish density affect the behavior of steelhead fry. We found that fry density had a significant effect on most response variables but that rearing treatment did not. The rates of threats and attacks were positively correlated with fry density, but the overall feeding rate was negatively correlated. Naturally reared fry were dominant more often at low densities, and hatchery-reared fry were dominant more often at high densities. There were no significant effects of hatchery rearing treatment on aggression, feeding, dominance, or territory size. The only significant effect of rearing treatment was on the position of naturally reared fry, which occupied more upstream positions when stocked with conventional than with enriched hatchery-reared fry. Overall, rearing environment had relatively little influence on the behavior of steelhead fry. Our results indicate that stocking hatchery-reared steelhead fry at low densities may have effects on similar-size wild fish comparable to an equivalent increase in the density of wild fish. We suggest that releasing hatchery-reared steelhead fry as a supplementation strategy may have few direct negative ecological effects on wild fry.

  1. Workers select mates for queens: a possible mechanism of gene flow restriction between supercolonies of the invasive Argentine ant

    NASA Astrophysics Data System (ADS)

    Sunamura, Eiriki; Hoshizaki, Sugihiko; Sakamoto, Hironori; Fujii, Takeshi; Nishisue, Koji; Suzuki, Shun; Terayama, Mamoru; Ishikawa, Yukio; Tatsuki, Sadahiro

    2011-05-01

    Some invasive ants form large networks of mutually non-aggressive nests, i.e., supercolonies. The Argentine ant Linepithema humile forms much larger supercolonies in introduced ranges than in its native range. In both cases, it has been shown that little gene flow occurs between supercolonies of this species, though the mechanism of gene flow restriction is unknown. In this species, queens do not undertake nuptial flight, and males have to travel to foreign nests and cope with workers before gaining access to alien queens. In this study, we hypothesized that male Argentine ants receive interference from workers of alien supercolonies. To test this hypothesis, we conducted behavioral and chemical experiments using ants from two supercolonies in Japan. Workers attacked males from alien supercolonies but not those from their own supercolonies. The level of aggression against alien males was similar to that against alien workers. The frequency of severe aggression against alien males increased as the number of recipient workers increased. Cuticular hydrocarbon profiles, which serve as cues for nestmate recognition, of workers and males from the same supercolony were very similar. Workers are likely to distinguish alien males from males of their own supercolony using the profiles. It is predicted that males are subject to considerable aggression from workers when they intrude into the nests of alien supercolonies. This may be a mechanism underlying the restricted gene flow between supercolonies of Argentine ants. The Argentine ant may possess a distinctive reproductive system, where workers participate in selecting mates for their queens. We argue that the aggression of workers against alien males is a novel form of reproductive interference.

  2. Progression of Mouse Skin Carcinogenesis Is Associated with Increased Erα Levels and Is Repressed by a Dominant Negative Form of Erα

    PubMed Central

    Michalopoulos, Ioannis; Sideridou, Maria; Tsimaratou, Katerina; Christodoulou, Ioannis; Pyrillou, Katerina; Gorgoulis, Vassilis; Vlahopoulos, Spiros; Zoumpourlis, Vassilis

    2012-01-01

    Estrogen receptors (ER), namely ERα and ERβ, are hormone-activated transcription factors with an important role in carcinogenesis. In the present study, we aimed at elucidating the implication of ERα in skin cancer, using chemically-induced mouse skin tumours, as well as cell lines representing distinct stages of mouse skin oncogenesis. First, using immunohistochemical staining we showed that ERα is markedly increased in aggressive mouse skin tumours in vivo as compared to the papilloma tumours, whereas ERβ levels are low and become even lower in the aggressive spindle tumours of carcinogen-treated mice. Then, using the multistage mouse skin carcinogenesis model, we showed that ERα gradually increases during promotion and progression stages of mouse skin carcinogenesis, peaking at the most aggressive stage, whereas ERβ levels only slightly change throughout skin carcinogenesis. Stable transfection of the aggressive, spindle CarB cells with a dominant negative form of ERα (dnERα) resulted in reduced ERα levels and reduced binding to estrogen responsive elements (ERE)-containing sequences. We characterized two highly conserved EREs on the mouse ERα promoter through which dnERα decreased endogenous ERα levels. The dnERα-transfected CarB cells presented altered protein levels of cytoskeletal and cell adhesion molecules, slower growth rate and impaired anchorage-independent growth in vitro, whereas they gave smaller tumours with extended latency period of tumour onset in vivo. Our findings suggest an implication of ERα in the aggressiveness of spindle mouse skin cancer cells, possibly through regulation of genes affecting cell shape and adhesion, and they also provide hints for the effective targeting of spindle cancer cells by dnERα. PMID:22870269

  3. Aggressive spinal haemangiomas: imaging correlates to clinical presentation with analysis of treatment algorithm and clinical outcomes

    PubMed Central

    Cloran, Francis J; Pukenas, Bryan A; Loevner, Laurie A; Aquino, Christopher; Schuster, James

    2015-01-01

    Objective: Aggressive spinal haemangiomas (those with significant osseous expansion/extraosseous extension) represent approximately 1% of spinal haemangiomas and are usually symptomatic. In this study, we correlate imaging findings with presenting symptomatology, review treatment strategies and their outcomes and propose a treatment algorithm. Methods: 16 patients with aggressive haemangiomas were retrospectively identified from 1995 to 2013. Imaging was assessed for size, location, CT/MR characteristics, osseous expansion and extraosseous extension. Presenting symptoms, management and outcomes were reviewed. Results: Median patient age was 52 years. Median size was 4.5 cm. Lumbar spine was the commonest location (n = 8), followed by thoracic spine (n = 7) and sacrum (n = 2); one case involved the lumbosacral junction. 12 haemangiomas had osseous expansion; 13 had extraosseous extension [epidural (n = 11), pre-vertebral/paravertebral (n = 10) and foraminal (n = 6)]. On CT, 11 had accentuated trabeculae and 5 showed lysis. On MRI, eight were T1 hyperintense, six were T1 hypointense and all were T2 hyperintense. 11 symptomatic patients underwent treatment: chemical ablation (n = 6), angioembolization (n = 3, 2 had subsequent surgery), radiotherapy (n = 2, 1 primary and 1 adjuvant) and surgery (n = 4). Median follow-up was 20 months. Four of six patients managed only by percutaneous methods had symptom resolution. Three of four patients requiring surgery had symptom resolution. Conclusion: Aggressive haemangiomas cause significant morbidity. Treatment is multidisciplinary, with surgery reserved for large lesions and those with focal neurological signs. Minimally invasive procedures may be successful in smaller lesions. Advances in knowledge: Aggressive haemangiomas are rare, but knowledge of their imaging features and treatment strategies enhances the radiologist's role in their management. PMID:26313498

  4. Chemical disguise of myrmecophilous cockroaches and its implications for understanding nestmate recognition mechanisms in leaf-cutting ants.

    PubMed

    Nehring, Volker; Dani, Francesca R; Calamai, Luca; Turillazzi, Stefano; Bohn, Horst; Klass, Klaus-Dieter; d'Ettorre, Patrizia

    2016-08-05

    Cockroaches of the genus Attaphila regularly occur in leaf-cutting ant colonies. The ants farm a fungus that the cockroaches also appear to feed on. Cockroaches disperse between colonies horizontally (via foraging trails) and vertically (attached to queens on their mating flights). We analysed the chemical strategies used by the cockroaches to integrate into colonies of Atta colombica and Acromyrmex octospinosus. Analysing cockroaches from nests of two host species further allowed us to test the hypothesis that nestmate recognition is based on an asymmetric mechanism. Specifically, we test the U-present nestmate recognition model, which assumes that detection of undesirable cues (non-nestmate specific substances) leads to strong rejection of the cue-bearers, while absence of desirable cues (nestmate-specific substances) does not necessarily trigger aggression. We found that nests of Atta and Acromyrmex contained cockroaches of two different and not yet described Attaphila species. The cockroaches share the cuticular chemical substances of their specific host species and copy their host nest's colony-specific cuticular profile. Indeed, the cockroaches are accepted by nestmate but attacked by non-nestmate ant workers. Cockroaches from Acromyrmex colonies bear a lower concentration of cuticular substances and are less likely to be attacked by non-nestmate ants than cockroaches from Atta colonies. Nest-specific recognition of Attaphila cockroaches by host workers in combination with nest-specific cuticular chemical profiles suggest that the cockroaches mimic their host's recognition labels, either by synthesizing nest-specific substances or by substance transfer from ants. Our finding that the cockroach species with lower concentration of cuticular substances receives less aggression by both host species fully supports the U-present nestmate recognition model. Leaf-cutting ant nestmate recognition is thus asymmetric, responding more strongly to differences than to similarities.

  5. Preference for Male Traits Differ in Two Female Morphs of the Tree Lizard, Urosaurus ornatus

    PubMed Central

    Lattanzio, Matthew S.; Metro, Kevin J.; Miles, Donald B.

    2014-01-01

    Non-random female mating preferences may contribute to the maintenance of phenotypic variation in color polymorphic species. However, the effect of female preference depends on the types of male traits used as signals by receptive females. If preference signals derive from discrete male traits (i.e., morph-specific), female preferences may rapidly fix to a morph. However, female preference signals may also include condition-dependent male traits. In this scenario, female preference may differ depending on the social context (i.e., male morph availability). Male tree lizards (Urosaurus ornatus) exhibit a dewlap color polymorphism that covaries with mating behavior. Blue morph males are aggressive and defend territories, yellow males are less aggressive and defend smaller territories, and orange males are typically nomadic. Female U. ornatus are also polymorphic in dewlap color, but the covariation between dewlap color and female behavior is unknown. We performed an experiment to determine how female mate choice depends on the visual and chemical signals produced by males. We also tested whether female morphs differ in their preferences for these signals. Female preferences involved both male dewlap color and size of the ventral color patch. However, the female morphs responded to these signals differently and depended on the choice between the types of male morphs. Our experiment revealed that females may be capable of distinguishing among the male morphs using chemical signals alone. Yellow females exhibit preferences based on both chemical and visual signals, which may be a strategy to avoid ultra-dominant males. In contrast, orange females may prefer dominant males. We conclude that female U. ornatus morphs differ in mating behavior. Our findings also provide evidence for a chemical polymorphism among male lizards in femoral pore secretions. PMID:25033282

  6. Hydroxyapatite Effect on Photopolymerization of Self-etching Adhesives with Different Aggressiveness

    PubMed Central

    Zhang, Ying; Wang, Yong

    2012-01-01

    Objective To understand the correlation of the acidic monomer/hydroxyapatite (HAp) reaction with the photopolymerization behavior of self-etching adhesives with different aggressiveness. Methods Two commercial self-etching adhesives the strong Adper Prompt L-Pop (APLP, pH~0.8) and the mild Adper Easy Bond (AEB, pH~2.5) were used. HAp powders were incorporated into both adhesives to acquire solutions with concentrations of 0, 1, 3, 5, 7 wt%. The attenuated total reflectance Fourier transform infrared (ATR/FT-IR) technique was employed to collect the in-situ spectra during light-curing, from which the degree of conversion (DC) and polymerization rate (PR) were calculated. The pH of each tested solution was also measured. Results Without HAp incorporation, the DC and PR of the strong APLP (7.8% and 0.12%/s, respectively) were much lower than those of the mild AEB (85.5% and 5.7%/s, respectively). The DC and PR of APLP displayed an apparent increasing trend with the HAp content. For example, the DC increased from 7.8% to 58.4% and the PR increased from 0.12 to 3.8%/s when the HAp content increased from 0 to 7 wt%. In contrast, the DC and PR of AEB were much less affected by the HAp content. The observations were correlated well with the spectral and pH changes, which indicated that APLP underwent a higher extent of chemical reaction with HAp than AEB. Conclusions The results disclosed the important role of the acidic monomer/HAp chemical reaction in improving the photopolymerization of the strong (low-pH) self-etching adhesives such as APLP. The phenomenon of polymerization improvement strongly depended on the adhesive aggressiveness. PMID:22445789

  7. Towards Cluster-Assembled Materials of True Monodispersity in Size and Chemical Environment: Synthesis, Dynamics and Activity

    DTIC Science & Technology

    2016-10-27

    AFRL-AFOSR-UK-TR-2016-0037 Towards cluster-assembled materials of true monodispersity in size and chemical environment: Synthesis, Dynamics and...Towards cluster-assembled materials of true monodispersity in size and chemical environment: synthesis, dynamics and activity 5a.  CONTRACT NUMBER 5b...report Towards cluster-assembled materials of true monodispersity in size and chemical environment: Synthesis, Dynamics and Activity Ulrich Heiz

  8. Safer Chemicals Research

    EPA Pesticide Factsheets

    EPA's Chemical Safety research protects human health and the environment by evaluating chemicals for potential risk and providing tools and guidance for improved chemical production that supports a sustainable environment.

  9. Aggressive behavior of the male parent predicts brood sex ratio in a songbird

    NASA Astrophysics Data System (ADS)

    Szász, Eszter; Garamszegi, László Zsolt; Hegyi, Gergely; Szöllősi, Eszter; Markó, Gábor; Török, János; Rosivall, Balázs

    2014-08-01

    Brood sex ratio is often affected by parental or environmental quality, presumably in an adaptive manner that is the sex that confers higher fitness benefits to the mother is overproduced. So far, studies on the role of parental quality have focused on parental morphology and attractiveness. However, another aspect, the partner's behavioral characteristics, may also be expected to play a role in brood sex ratio adjustment. To test this hypothesis, we investigated whether the proportion of sons in the brood is predicted by the level of territorial aggression displayed by the father, in the collared flycatcher ( Ficedula albicollis). The proportion of sons in the brood was higher in early broods and increased with paternal tarsus length. When controlling for breeding date and body size, we found a higher proportion of sons in the brood of less aggressive fathers. Male nestlings are more sensitive to the rearing environment, and the behavior of courting males may often be used by females to assess their future parental activity. Therefore, adjusting brood sex ratio to the level of male aggression could be adaptive. Our results indicate that the behavior of the partner could indeed be a significant determinant in brood sex ratio adjustment, which should not be overlooked in future studies.

  10. Can outcomes of dyadic interactions be consistent across contexts among wild zebrafish?

    PubMed Central

    Roy, Tamal; Bhat, Anuradha

    2015-01-01

    Winner–loser relations among group-living individuals are often measured by the levels of aggressive interactions between them. These interactions are typically driven by competition for resources such as food and mates. It has been observed in recent studies on zebrafish that dominant males generally have higher total reproductive success than their less aggressive subordinate counterparts. This study aimed to test whether males who monopolized a food resource (winners) also displayed higher levels of aggression than the males who were unsuccessful (losers). Further, the study also tested whether the same ‘winner’ males were also able to monopolize interactions with females during courtship. The results from these experiments showed that while males monopolizing food resources (winners) demonstrated higher levels of agonistic interactions than the losers, the average number of courtship interactions initiated by either of the males (i.e. winners/losers) with a female was not significantly different. A significant relationship was obtained between the number of aggressive interactions and feeding latencies of males in the context of food monopolization. This indicated that there could be a linkage between boldness defined by feeding latency in a novel environment and agonistic responses. The probable role of nature of resources, resource availability and distribution in determining the outcomes of dyadic contests is discussed. PMID:26715992

  11. Controlling Sulfate Attack in Mississippi Department of Transportation Structures

    DTIC Science & Technology

    2010-08-01

    exposed to aggressive sulfate environments. Cement and Concrete Composites 24 :305–316. Al-Dulaijan, S., U . M. Maslehuddin, M. M. Al-Zahrani, A. M... 24 Appendix D: ASTM C1012 Photographs ........................................................................................... 39... 24 Figure C2. Length change vs. time of exposure for mortar mix 2

  12. Defamation Charges in a Networked Environment.

    ERIC Educational Resources Information Center

    Ferencz, Susan K.

    1997-01-01

    Considers how civil law might treat claims of defamation arising from computer newsgroup postings. Concludes that newsgroup postings will probably be treated as a hybrid of print and broadcast media, and that newsgroup users will vigorously and aggressively protect freedoms of speech and press. While traditional defenses to defamation charges will…

  13. Impact of Cumulative Combat Stress on Learning in an Academic Environment

    ERIC Educational Resources Information Center

    Shea, Kevin Peter; Fishback, Sarah Jane

    2012-01-01

    The stress of multiple combat tours has created a combat-tested but combat-weary Army. While most soldiers have coped successfully with combat stress, many return home with problems that include posttraumatic stress disorder (PTSD), depression, anxiety, aggressive behavior, insomnia, and reduced memory and concentration skills. Education is…

  14. Confronting Transnational Organized Crime: Getting It Right to Forestall a New National Security Threat

    DTIC Science & Technology

    2013-01-01

    about them. These franchises operate in, and control, specific geographic territories that allow them to function in a relatively safe environment...businesses should be paired with aggressive non–law enforcement engagement and social services in a coor- dinated fashion . This type of coordination

  15. Little Witnesses, Secret Wounds. Issues in Education.

    ERIC Educational Resources Information Center

    Erdiller, Zeynep B.

    2003-01-01

    Uses social learning theory to examine the possible effects of parental domestic violence on children who witness it in their home environment. Examines the short-term and long-term influence of witnessing parental violence on children's development, including aggression among peers during childhood and adolescence, as well as in dating…

  16. Developing a Game Plan for Good Sportsmanship

    ERIC Educational Resources Information Center

    Lodl, Kathleen

    2005-01-01

    Research indicates that competition can be an important context whereby youth gain positive outcomes such as intrinsic motivation and engagement in the environment. However, other studies indicate that sports activities may also relate to negative outcomes such as aggression and cheating. One of the challenges for educators and youth development…

  17. Maternal Distress Explains the Relationship of Young African American Mothers' Violence Exposure with Their Preschoolers' Behavior

    ERIC Educational Resources Information Center

    Mitchell, Stephanie J.; Lewin, Amy; Rasmussen, Andrew; Horn, Ivor B.; Joseph, Jill G.

    2011-01-01

    Adolescent mothers and their children are particularly susceptible to witnessing or directly experiencing violence. Such violence exposure predicts maternal distress, parenting, and child behavior problems. The current study examined how mothers' depressive symptoms, aggression, harsh disciplinary practices, and home environment independently…

  18. Chemical terrorism for the intensivist.

    PubMed

    Chalela, Julio A; Burnett, Thomas

    2012-05-01

    The use of chemical agents for terrorist attacks or military warfare is a major concern at the present time. Chemical agents can cause significant morbidity, are relatively inexpensive, and are easy to store and use. Weaponization of chemical agents is only limited by the physicochemical properties of some agents. Recent incidents involving toxic industrial chemicals and chemical terrorist attacks indicate that critical care services are frequently utilized. For obvious reasons, the critical care literature on chemical terrorism is scarce. This article reviews the clinical aspects of diagnosing and treating victims of chemical terrorism while emphasizing the critical care management. The intensivist needs to be familiar with the chemical agents that could be used in a terrorist attack. The military classification divides agents into lung agents, blood agents, vesicants, and nerve agents. Supportive critical care is the cornerstone of treatment for most casualties, and dramatic recovery can occur in many cases. Specific antidotes are available for some agents, but even without the antidote, aggressive intensive care support can lead to favorable outcome in many cases. Critical care and emergency services can be overwhelmed by a terrorist attack as many exposed but not ill will seek care.

  19. Within-season variability of fighting behaviour in an Australian alpine grasshopper

    PubMed Central

    Muschett, Giselle; Umbers, Kate D. L.; Herberstein, Marie E.

    2017-01-01

    Throughout the breeding season, changing environmental and biological conditions can lead to variation in the reproductive landscape of many species. In alpine environments temperature is a key driver of behaviour for small ectotherms such as insects, but variable biotic factors such as mate quality and availability can also influence behaviour. Kosicuscola tristis is a small semelparous grasshopper of the Australian alpine region. In a rare behaviour among grasshoppers, K. tristis males engage in vigorous fights over access to females, involving mandible displays, kicking, biting and grappling. In this study we describe the variation in fighting behaviour of K. tristis throughout the breeding season and test several hypotheses related to temperature, body size, mating behaviour, and female quality. We show that K. tristis males are more aggressive toward each other at the end of the breeding season than at the beginning. This increased aggression is associated with decreased daily average temperatures (from ~20°C to ~9°C), decreased mating activity, increased female fecundity, and an unexpected trend toward an increase in female-to-male aggression. These results suggest that K. tristis is likely under increased selective pressure to time key life cycle events with favourable biological and climatic conditions. The stochastic nature of alpine environments combined with a relatively short life span and breeding season, as well as limited mating opportunities toward the end of the season may have contributed to the evolution of this extraordinary mating system. PMID:28403243

  20. Toward a Mouse Neuroethology in the Laboratory Environment

    PubMed Central

    Hellier, Jennifer L.; Ly, Xuan; Koka, Kanthaiah; Tollin, Daniel J.; Restrepo, Diego

    2010-01-01

    In this report we demonstrate that differences in cage type brought unexpected effects on aggressive behavior and neuroanatomical features of the mouse olfactory bulb. A careful characterization of two cage types, including a comparison of the auditory and temperature environments, coupled with a demonstration that naris occlusion abolishes the neuroanatomical changes, lead us to conclude that a likely important factor mediating the phenotypic changes we find is the olfactory environment of the two cages. We infer that seemingly innocuous changes in cage environment can affect sensory input relevant to mice and elicit profound effects on neural output. Study of the neural mechanisms underlying animal behavior in the laboratory environment should be broadened to include neuroethological approaches to examine how the laboratory environment (beyond animal well-being and enrichment) influences neural systems and behavior. PMID:20613876

  1. Influence of coating defects on the corrosion behavior of cold sprayed refractory metals

    NASA Astrophysics Data System (ADS)

    Kumar, S.; Rao, A. Arjuna

    2017-02-01

    The defects in the cold sprayed coatings are critical in the case of corrosion performances of the coatings in aggressive conditions. To understand the influence of coating defects on corrosion, immersion tests have been carried out in HF solution for the cold sprayed and heat treated Titanium, Tantalum and Niobium coatings. Long duration immersion tests reveal inhomogeneous weight losses of the samples prepared at different heat treatment conditions. The weight loss for different coatings has been well corroborated with the coating defects and microstructures. Chemical and micro structural analysis elucidates the reason behind the inhomogeneous performance of different type of cold sprayed coatings in corrosion medium. In the case of cold sprayed titanium, formation of stable oxide along the inter-splat boundary hinders the aggressive attack of the corrosion medium which is not so in other cases.

  2. X-ray coherent diffraction imaging of cellulose fibrils in situ.

    PubMed

    Lal, Jyotsana; Harder, Ross; Makowski, Lee

    2011-01-01

    Cellulose is the most abundant renewable source of organic molecules on earth[1]. As fossil fuel reserves become depleted, the use of cellulose as a feed stock for fuels and chemicals is being aggressively explored. Cellulose is a linear polymer of glucose that packs tightly into crystalline fibrils that make up a substantial proportion of plant cell walls. Extraction of the cellulose chains from these fibrils in a chemically benign process has proven to be a substantial challenge [2]. Monitoring the deconstruction of the fibrils in response to physical and chemical treatments would expedite the development of efficient processing methods. As a step towards achieving that goal, we here describe Bragg-coherent diffraction imaging (CDI) as an approach to producing images of cellulose fibrils in situ within vascular bundles from maize.

  3. Gender-specific impairments on cognitive and behavioral development in mice exposed to fenvalerate during puberty.

    PubMed

    Meng, Xiu-Hong; Liu, Ping; Wang, Hua; Zhao, Xian-Feng; Xu, Zhong-Mei; Chen, Gui-Hai; Xu, De-Xiang

    2011-06-24

    In human and rodent models, endocrine disrupting chemicals (EDCs) interfere with the development of cognition and behaviors. Fenvalerate is a potential EDC. The purpose of this study was to examine whether pubertal fenvalerate exposure altered behavioral development. Mice were orally administered with either vehicle or fenvalerate (7.5 or 30 mg/kg/day) from postnatal day (PND) 28 to PND56. Learning and memory were assessed by Morris Water Maze. Aggressive performance was evaluated by aggressive behavior test. Anxiety-related activities were detected by three tests: open-field, plus-maze and black-white alley. Sensorimotor function was analyzed using beam walking and tightrope. Results found that the impairment for spatial learning and memory was more severe in fenvalerate-exposed female mice than in male mice. In addition, pubertal fenvalerate exposure inhibited aggressive behavior in males. Moreover, pubertal fenvalerate exposure increased anxiety activities in females. Altogether, these results suggest that pubertal fenvalerate exposure impairs spatial cognition and behavioral development in a gender-dependent manner. These findings identify fenvalerate as candidate environmental risk factors for cognitive and behavioral development, especially in the critical period of development. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  4. Symbiotic flagellate protists as cryptic drivers of adaptation and invasiveness of the subterranean termite Reticulitermes grassei Clément.

    PubMed

    Duarte, Sónia; Nobre, Tânia; Borges, Paulo A V; Nunes, Lina

    2018-06-01

    Changes in flagellate protist communities of subterranean termite Reticulitermes grassei across different locations were evaluated following four predictions: (i) Rural endemic (Portugal mainland) termite populations will exhibit high diversity of symbionts; (ii) invasive urban populations (Horta city, Faial island, Azores), on the contrary, will exhibit lower diversity of symbionts, showing high similarity of symbiont assemblages through environmental filtering; (iii) recent historical colonization of isolated regions-as the case of islands-will imply a loss of symbiont diversity; and (iv) island isolation will trigger a change in colony breeding structure toward a less aggressive behavior. Symbiont flagellate protist communities were morphologically identified, and species richness and relative abundances, as well as biodiversity indices, were used to compare symbiotic communities in colonies from urban and rural environments and between island invasive and mainland endemic populations. To evaluate prediction on the impact of isolation (iv), aggression tests were performed among termites comprising island invasive and mainland endemic populations. A core group of flagellates and secondary facultative symbionts was identified. Termites from rural environments showed, in the majority of observed colonies, more diverse and abundant protist communities, probably confirming prediction (i). Corroborating prediction (ii), the two least diverse communities belong to termites captured inside urban areas. The Azorean invasive termite colonies had more diverse protist communities than expected and prediction (iii) which was not verified within this study. Termites from mainland populations showed a high level of aggressiveness between neighboring colonies, in contrast to the invasive colonies from Horta city, which were not aggressive to neighbors according to prediction (iv). The symbiotic flagellate community of R. grassei showed the ability to change in a way that might be consistent with adaptation to available conditions, possibly contributing to optimization of the colonization of new habitats and spreading of its distribution area, highlighting R. grassei potential as an invasive species.

  5. Development of Anticorrosive Polymer Nanocomposite Coating for Corrosion Protection in Marine Environment

    NASA Astrophysics Data System (ADS)

    Mardare, L.; Benea, L.

    2017-06-01

    The marine environment is considered to be a highly aggressive environment for metal materials. Steels are the most common materials being used for shipbuilding. Corrosion is a major cause of structural deterioration in marine and offshore structures. Corrosion of carbon steel in marine environment becomes serious due to the highly corrosive nature of seawater with high salinity and microorganism. To protect metallic materials particularly steel against corrosion occurrence various organic and inorganic coatings are used. The most used are the polymeric protective coatings. The nanostructured TiO2 polymer coating is able to offer higher protection to steel against corrosion, and performed relatively better than other polymer coatings.

  6. Gene-Environment Studies and Borderline Personality Disorder: A Review

    PubMed Central

    Carpenter, Ryan W.; Tomko, Rachel L.; Boomsma, Dorret I.

    2014-01-01

    We review recent gene-environment studies relevant to borderline personality disorder, including those focusing on impulsivity, emotion sensitivity, suicidal behavior, aggression and anger, and the borderline personality phenotype itself. Almost all the studies reviewed suffered from a number of methodological and statistical problems, limiting the conclusions that currently can be drawn. The best evidence to date supports a gene-environment correlation (rGE) model for borderline personality traits and a range of adverse life events, indicating that those at risk for BPD are also at increased risk for exposure to environments that may trigger BPD. We provide suggestions regarding future research on GxE interaction and rGE effects in borderline personality. PMID:23250817

  7. Corrosion Development of Carbon Steel Grids and Shear Connectors in Cracked Composite Beams Exposed to Wet–Dry Cycles in Chloride Environment

    PubMed Central

    Xue, Wen; Chen, Ju; Jiang, Ao-yu

    2018-01-01

    The corrosion development of the reinforcement and shear stud connectors in the cracked steel–concrete composite beams under the salt-fog wet–dry cycles is presented in this investigation. Seven identical composite beams with load-induced concrete cracks were exposed to an aggressive chloride environment. The reinforcement and shear connectors were retrieved after specimens underwent a specified number of wet–dry cycles to obtain the corrosion pattern and the cross-section loss at different exposure times and their evolutions. The crack map, the corrosion pattern and the cross-section loss were measured and presented. Based on the experimental results, the influence of crack characteristics, including crack widths, orientations and positions on the corrosion rate and distribution, were accessed. Moreover, the effects of the connecting weldments on the corrosion initiations and patterns were analyzed. It was shown that the corrosion rate would increase with the number of wet–dry cycles. The characteristics of load-induced cracks could have different influences on the steel grids and shear stud connectors. The corrosion tended to initiate from the connecting weldments, due to the potential difference with the parent steel and the aggressive exposure environment, leading to a preferential weldment attack. PMID:29565836

  8. Review of Non-Chemical Stressors from the Social Environment

    EPA Science Inventory

    Non-chemical stressors (e.g., noise, diet, temperature, overcrowding) are found in the built, natural and social environments. Correlations between exposure to non-chemical stressors in the social environment (e.g., SES, exposure to violence, acculturation) and negative health ou...

  9. ENERGETICS AND CHEMICAL KINETICS OF POLYSTYRENE SURFACE DEGRADATION IN INERT AND CHEMICALLY REACTIVE ENVIRONMENTS.

    DTIC Science & Technology

    gases were passed to emerge at the heated surface, permitted these data to be gathered in chemically reactive environments. Correlation of all these data...in both inert and chemically reactive environments, was possible both on the basis of an energy balance struck at the regressing surface and an...Arrhenius type of chemical kinetic description of the surface degradation process. Although expected, this represents the first demonstration that both

  10. Nuclear forensics: Soil content

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

    Beebe, Merilyn Amy

    Nuclear Forensics is a growing field that is concerned with all stages of the process of creating and detonating a nuclear weapon. The main goal is to prevent nuclear attack by locating and securing nuclear material before it can be used in an aggressive manner. This stage of the process is mostly paperwork; laws, regulations, treaties, and declarations made by individual countries or by the UN Security Council. There is some preliminary leg work done in the form of field testing detection equipment and tracking down orphan materials; however, none of these have yielded any spectacular or useful results. Inmore » the event of a nuclear attack, the first step is to analyze the post detonation debris to aid in the identification of the responsible party. This aspect of the nuclear forensics process, while reactive in nature, is more scientific. A rock sample taken from the detonation site can be dissolved into liquid form and analyzed to determine its chemical composition. The chemical analysis of spent nuclear material can provide valuable information if properly processed and analyzed. In order to accurately evaluate the results, scientists require information on the natural occurring elements in the detonation zone. From this information, scientists can determine what percentage of the element originated in the bomb itself rather than the environment. To this end, element concentrations in soils from sixty-nine different cities are given, along with activity concentrations for uranium, thorium, potassium, and radium in various building materials. These data are used in the analysis program Python.« less

  11. Influence of prior residents on settlement preferences in the anemonefish, Premnas biaculeatus

    NASA Astrophysics Data System (ADS)

    Dixson, Danielle L.; Jones, Geoffrey P.

    2018-06-01

    Settlement preferences play a critical role in the successful transition from pelagic larvae to benthic juveniles for many coral reef organisms. Reef fish larvae are capable of recognizing and behaviorally responding to a variety of sensory cues when assessing settlement site locations. The presence of resident conspecifics for site attached coral reef fishes could indicate a quality location, but may result in negative interactions through aggression from already-established individuals. For anemonefishes, where space on a sea anemone is limited and breeding is restricted to one adult pair, settlement preferences may depend on the number and sex of the occupants. Here we undertook both aquarium-based olfactory trials and a field experiment to determine the role resident anemonefish individuals have on sea anemone site selection in the spine cheek anemonefish, Premnas biaculeatus. We show larvae are able to identify the occupant saturation state and sex of the resident occupants based on chemical cues alone, with larvae preferring the chemical cues produced by a single male to a single female, the single fish to an empty sea anemone, and an empty sea anemone to a sea anemone containing an adult pair. These behavioral preferences were reflected in the settlement preferences of larvae when assessed in the natural environment. We hypothesize that the ability of resident fish to evict incoming larvae combined with the selective pressure on larvae to locate an ideal habitat has resulted in the larval ability to accurately identify habitat where settlement and future breeding opportunities are most likely achieved.

  12. Investigation of corrosion of welded joints of austenitic and duplex stainless steels

    NASA Astrophysics Data System (ADS)

    Topolska, S.

    2016-08-01

    Investigation of corrosion resistance of materials is one of the most important tests that allow determining their functional properties. Among these tests the special group consist electrochemical investigations, which let to accelerate the course of the process. These investigations allow rapidly estimating corrosion processes occurring in metal elements under the influence of the analysed environment. In the paper are presented results of investigations of the resistance to pitting corrosion of the steel of next grades: austenitic 316L and duplex 2205. It was also analysed the corrosion resistance of welded joints of these grades of steel. The investigations were conducted in two different corrosion environments: in the neutral one (3.5 % sodium chloride) and in the aggressive one (0.1 M sulphuric acid VI). The obtained results indicate different resistance of analysed grades of steel and their welded joints in relation to the corrosion environment. The austenitic 316L steel characterizes by the higher resistance to the pitting corrosion in the aggressive environment then the duplex 2205 steel. In the paper are presented results of potentiodynamic tests. They showed that all the specimens are less resistant to pitting corrosion in the environment of sulphuric acid (VI) than in the sodium chloride one. The 2205 steel has higher corrosion resistance than the 316L stainless steel in 3.5% NaCl. On the other hand, in 0.1 M H2SO4, the 316L steel has a higher corrosion resistance than the 2205 one. The weld has a similar, very good resistance to pitting corrosion like both steels.

  13. Adolescent externalizing behaviour, psychological control, and peer rejection: Transactional links and dopaminergic moderation.

    PubMed

    Janssens, Annelies; Van Den Noortgate, Wim; Goossens, Luc; Verschueren, Karine; Colpin, Hilde; Claes, Stephan; Van Heel, Martijn; Van Leeuwen, Karla

    2017-09-01

    This study investigated (1) reciprocal links among parental psychological control, peer rejection, and adolescent externalizing (aggressive and rule-breaking behaviour), and (2) the moderating effect of an adolescent genetic factor (biologically informed polygenic score for dopamine signalling). Three-year longitudinal data from 1,116 adolescents (51% boys; M age = 13.79) and their parents included psychological measures (adolescent-reported psychological control, peer-reported rejection, and parent-reported aggressive and rule-breaking behaviour). Cross-lagged analyses showed bidirectional effects between psychological control and both aggressive and rule-breaking behaviour and a unidirectional effect of peer rejection on both forms of problem behaviour over time. Multigroup structural equation modelling revealed genetic moderation only for rule-breaking behaviour: for adolescents with intermediate levels of dopamine signalling significant environmental effects were present, whereas adolescent effects of rule-breaking behaviour on psychological control were significant for adolescents with both intermediate and high profiles and effects on peer rejection only for adolescents with high dopamine profiles. Statement of contribution What is already known on this subject? Parental psychological control is related to adolescent externalizing problems. Experiencing peer rejection reinforces aggressive and rule-breaking behaviour. Single-gene studies show that dopaminergic genes influence externalizing problems directly or in interaction with the environment. What does this study add? Parental psychological control and adolescent aggressive and rule-breaking behaviour exacerbate one another longitudinally. Longitudinal associations between peer rejection and both subtypes of externalizing behaviour are unidirectional. With a polygenic approach, dopaminergic moderation is present for rule-breaking behaviour only. © 2017 The British Psychological Society.

  14. Social interactions in Red Junglefowl (Gallus gallus) and White Leghorn layers in stable groups and after re-grouping.

    PubMed

    Väisänen, J; Håkansson, J; Jensen, P

    2005-04-01

    Although social behaviour is a major factor affecting the coping of poultry in production environments little is known about how it has been affected by intensive selection processes in fowl. We attempted to clarify selection effects on overall repertoire and occurrence of different social behaviours as well as on aggressive responses to re-grouping with unfamiliar birds by comparing high-producing White Leghorn layers to wild type Red Junglefowl. In the first experiment we observed 8 stable mixed sex groups/breed each consisting of four 24-week-old birds previously familiar to each other. During 9 consecutive days, a wide range of social signals, sexual and aggressive interactions as well as spacing behaviour and activity were recorded over a 12-h photoperiod. In the second experiment, starting at 19 weeks of age, 16 single sex groups of three birds from each breed were formed by mixing unfamiliar individuals. Aggressive behaviours were recorded 0, 5, 24 and 48 h after re-grouping. Results from the stable groups indicated that the repertoire of social behaviours has been preserved during selection with few changes in frequencies and intensities. However, Leghorns showed a more cohesive spacing pattern than junglefowl. In the second experiment, aggressive activity was higher immediately and after 24 h following re-grouping in Leghorns, but there was a drop in the aggressiveness at 5 h to the same level as junglefowl. We suggest that this may indicate poorer social learning capacity with a weaker ability to cope with group disruptions compared to the ancestral breed.

  15. The Influence of Media Violence on Youth.

    PubMed

    Anderson, Craig A; Berkowitz, Leonard; Donnerstein, Edward; Huesmann, L Rowell; Johnson, James D; Linz, Daniel; Malamuth, Neil M; Wartella, Ellen

    2003-12-01

    Research on violent television and films, video games, and music reveals unequivocal evidence that media violence increases the likelihood of aggressive and violent behavior in both immediate and long-term contexts. The effects appear larger for milder than for more severe forms of aggression, but the effects on severe forms of violence are also substantial (r = .13 to .32) when compared with effects of other violence risk factors or medical effects deemed important by the medical community (e.g., effect of aspirin on heart attacks). The research base is large; diverse in methods, samples, and media genres; and consistent in overall findings. The evidence is clearest within the most extensively researched domain, television and film violence. The growing body of video-game research yields essentially the same conclusions. Short-term exposure increases the likelihood of physically and verbally aggressive behavior, aggressive thoughts, and aggressive emotions. Recent large-scale longitudinal studies provide converging evidence linking frequent exposure to violent media in childhood with aggression later in life, including physical assaults and spouse abuse. Because extremely violent criminal behaviors (e.g., forcible rape, aggravated assault, homicide) are rare, new longitudinal studies with larger samples are needed to estimate accurately how much habitual childhood exposure to media violence increases the risk for extreme violence. Well-supported theory delineates why and when exposure to media violence increases aggression and violence. Media violence produces short-term increases by priming existing aggressive scripts and cognitions, increasing physiological arousal, and triggering an automatic tendency to imitate observed behaviors. Media violence produces long-term effects via several types of learning processes leading to the acquisition of lasting (and automatically accessible) aggressive scripts, interpretational schemas, and aggression-supporting beliefs about social behavior, and by reducing individuals' normal negative emotional responses to violence (i.e., desensitization). Certain characteristics of viewers (e.g., identification with aggressive characters), social environments (e.g., parental influences), and media content (e.g., attractiveness of the perpetrator) can influence the degree to which media violence affects aggression, but there are some inconsistencies in research results. This research also suggests some avenues for preventive intervention (e.g., parental supervision, interpretation, and control of children's media use). However, extant research on moderators suggests that no one is wholly immune to the effects of media violence. Recent surveys reveal an extensive presence of violence in modern media. Furthermore, many children and youth spend an inordinate amount of time consuming violent media. Although it is clear that reducing exposure to media violence will reduce aggression and violence, it is less clear what sorts of interventions will produce a reduction in exposure. The sparse research literature suggests that counterattitudinal and parental-mediation interventions are likely to yield beneficial effects, but that media literacy interventions by themselves are unsuccessful. Though the scientific debate over whether media violence increases aggression and violence is essentially over, several critical tasks remain. Additional laboratory and field studies are needed for a better understanding of underlying psychological processes, which eventually should lead to more effective interventions. Large-scale longitudinal studies would help specify the magnitude of media-violence effects on the most severe types of violence. Meeting the larger societal challenge of providing children and youth with a much healthier media diet may prove to be more difficult and costly, especially if the scientific, news, public policy, and entertainment communities fail to educate the general public about the real risks of media-violence exposure to children and youth. © 2003 Association for Psychological Science.

  16. Does the environmental background (intensive v. outdoor systems) influence the behaviour of piglets at weaning?

    PubMed

    Lau, Y Y W; Pluske, J R; Fleming, P A

    2015-08-01

    Under intensive pig husbandry, outdoor systems offer a more complex physical and social environment compared with indoor systems (farrowing sheds). As the rearing environment affects behavioural development, it can, therefore, influence behavioural responses of pigs to stressful environments in later stages of production. We tested how the rearing environment influenced behavioural responses to a novel arena test in piglets on the day that they were weaned and mixed into large groups. We recorded video footage and compared the behavioural responses of 30 outdoor-raised and 30 farrowing shed-raised piglets tested in an experimental arena and sequentially exposed to four challenges (each for 5 min) on the day of weaning. Quantitative and qualitative behavioural measures were recorded using time budgets and scoring demeanour or 'qualitative behavioural expression' (using Qualitative Behavioural Assessment (QBA)). When held in isolation (challenge 1), both groups were scored as more 'scared/worried', while outdoor-raised piglets spent more time eating and jumping against the arena walls. Both groups interacted with a plastic ball (challenge 2: exposure to a novel object) during which they were scored as more 'playful/curious' than other challenges. When a food bowl was introduced (challenge 3), farrowing shed-raised piglets were more interested in playing with the food bowl itself, whereas outdoor-raised piglets spent more time eating the feed. Finally, there were no significant differences in social behaviour (challenge 4: introduction of another piglet) between the two groups in terms of the latency to contact each other, amount of time recorded engaged in aggressive/non-aggressive social interactions or QBA scores. Although piglets spent 30% of their time interacting with the other piglet, and half of this time (47%) was engaged in negative interactions (pushing, biting), the levels of aggression were not different between the two groups. Overall, outdoor-raised piglets ate more and were scored as more 'calm/passive', whereas farrowing shed-raised piglets spent more time investigating their environment and were scored as more 'playful/inquisitive'. In conclusion, we did not find differences in behaviour between outdoor-raised and farrowing shed-raised piglets that would highlight welfare issues. The differences found in this study may reflect conflicting affective states, with responses to confinement, neophobia and motivation for exploration evident.

  17. Physical punishment and childhood aggression: the role of gender and gene-environment interplay.

    PubMed

    Boutwell, Brian B; Franklin, Cortney A; Barnes, J C; Beaver, Kevin M

    2011-01-01

    A large body of research has linked spanking with a range of adverse outcomes in children, including aggression, psychopathology, and criminal involvement. Despite evidence concerning the association of spanking with antisocial behavior, not all children who are spanked develop antisocial traits. Given the heterogeneous effects of spanking on behavior, it is possible that a third variable may condition the influence of corporal punishment on child development. We test this possibility using data drawn from a nationally representative dataset of twin siblings. Our findings suggest that genetic risk factors condition the effects of spanking on antisocial behavior. Moreover, our results provide evidence that the interaction between genetic risk factors and corporal punishment may be particularly salient for males. © 2011 Wiley Periodicals, Inc.

  18. Corrosion Performance of Inconel 625 in High Sulphate Content

    NASA Astrophysics Data System (ADS)

    Ismail, Azzura

    2016-05-01

    Inconel 625 (UNS N06625) is a type of nickel-chromium-molybdenum alloy with excellent corrosion resistance in a wide range of corrosive media, being especially resistant to pitting and crevice corrosion. However, in aggressive environment, Inconel 625 will suffer corrosion attack like other metals. This research compared the corrosion performance of Inconel 625 when exposed to higher sulphate content compared to real seawater. The results reveal that Inconel 625 is excellent in resist the corrosion attack in seawater. However, at increasing temperature, the corrosion resistance of this metal decrease. The performance is same in seawater with high sulphate content at increasing temperature. It can be concluded that sulphate promote perforation on Inconel 625 and become aggressive agents that accelerate the corrosion attack.

  19. Evolution and the psychology of intergroup conflict: the male warrior hypothesis.

    PubMed

    McDonald, Melissa M; Navarrete, Carlos David; Van Vugt, Mark

    2012-03-05

    The social science literature contains numerous examples of human tribalism and parochialism-the tendency to categorize individuals on the basis of their group membership, and treat ingroup members benevolently and outgroup members malevolently. We hypothesize that this tribal inclination is an adaptive response to the threat of coalitional aggression and intergroup conflict perpetrated by 'warrior males' in both ancestral and modern human environments. Here, we describe how male coalitional aggression could have affected the social psychologies of men and women differently and present preliminary evidence from experimental social psychological studies testing various predictions from the 'male warrior' hypothesis. Finally, we discuss the theoretical implications of our research for studying intergroup relations both in humans and non-humans and discuss some practical implications.

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

    Hillmer, Kurt T.

    This report focuses on the detection and control of radioactive contamination, which are an integral part of an aggressive ALARA program and provide an indication of the effectiveness of engineering controls and proper work practices in preventing the release of radioactive material. Radioactive contamination, if undetected or not properly controlled, can be spread and contaminate areas, equipment, personnel, and the environment.

  1. Evaluating Video Self-Modeling Treatment Outcomes: Differentiating between Statistically and Clinically Significant Change

    ERIC Educational Resources Information Center

    La Spata, Michelle G.; Carter, Christopher W.; Johnson, Wendi L.; McGill, Ryan J.

    2016-01-01

    The present study examined the utility of video self-modeling (VSM) for reducing externalizing behaviors (e.g., aggression, conduct problems, hyperactivity, and impulsivity) observed within the classroom environment. After identification of relevant target behaviors, VSM interventions were developed for first and second grade students (N = 4),…

  2. The Behavioural Phenotype of Smith-Magenis Syndrome: Evidence for a Gene-Environment Interaction

    ERIC Educational Resources Information Center

    Taylor, L.; Oliver, C.

    2008-01-01

    Background: Behaviour problems and a preference for adult contact are reported to be prominent in the phenotype of Smith-Magenis syndrome. In this study we examined the relationship between social interactions and self-injurious and aggressive/disruptive behaviour in Smith-Magenis syndrome to explore potential operant reinforcement of problem…

  3. Click: The Twelfth Annual Report on Schoolhouse Commercialism Trends, 2008-2009

    ERIC Educational Resources Information Center

    Molnar, Alex; Boninger, Faith; Wilkinson, Gary; Fogarty, Joseph

    2009-01-01

    As part of their efforts to create a total advertising environment, companies continue to aggressively market in school to children and youth. Advertisers now routinely blur the boundaries between editorial content and advertising in an effort to thoroughly infuse childhood with marketing messages. The goal of creating a total advertising…

  4. Oceanography for Divers: Hazardous Marine Life. Diver Education Series.

    ERIC Educational Resources Information Center

    Somers, Lee H.

    Most people find that the life of the marine environment is beautiful and fascinating. Of the thousands of marine animals and plants, relatively few constitute a real hazard to the diver. Although some species are dangerous and may, in some instances, inflict serious wounds, with a few exceptions marine animals are not aggressive. Most…

  5. Connecting Children to Nature: A Multiple Case Study of Nature Center Preschools

    ERIC Educational Resources Information Center

    Bailie, Patti Ensel

    2012-01-01

    Environmental degradation, childhood obesity, and aggression of youth are societal problems that appear unconnected. However, their cause (and possible solution) may be linked to a common experience--the amount and quality of time spent in the natural world. Environment based education, significant life experience research, and studies involving…

  6. The Behavior of Environmentally Friendly Corrosion Preventative Compounds in an Aggressive Coastal Marine Environment

    NASA Technical Reports Server (NTRS)

    Montgomery, Eliza L.; Calle, Luz Marina; Curran Jerome C.; Kolody, Mark R.

    2013-01-01

    The shift to use environmentally friendly technologies throughout future space-related launch programs prompted a study aimed at replacing current petroleum and solvent-based Corrosion Preventive Compounds (CPCs) with environmentally friendly alternatives. The work in this paper focused on the identification and evaluation of environmentally friendly CPCs for use in protecting flight hardware and ground support equipment from atmospheric corrosion. The CPCs, while a temporary protective coating, must survive in the aggressive coastal marine environment that exists throughout the Kennedy Space Center, Florida. The different protection behaviors of fifteen different soft film CPCs, both common petroleum-based and newer environmentally friendly types, were evaluated on various steel and aluminum substrates. The CPC and substrate systems were subjected to atmospheric testing at the Kennedy Space Center's Beachside Atmospheric Corrosion Test Site, as well as cyclic accelerated corrosion testing. Each CPC also underwent physical characterization and launch-related compatibility testing . The initial results for the fifteen CPC systems are reported : Key words: corrosion preventive compound, CPC, spaceport, environmentally friendly, atmospheric exposure, marine, carbon steel, aluminum alloy, galvanic corrosion, wire on bolt.

  7. Scaling and saturation laws for the expansion of concrete exposed to sulfate attack.

    PubMed

    Monteiro, Paulo J M

    2006-08-01

    Reinforced concrete structures exposed to aggressive environments often require repair or retrofit even though they were designed to last >50 years. This statement is especially true for structures subjected to sulfate attack. It is critical that fundamental models of life prediction be developed for durability of concrete. Based on experimental results obtained over a 40-year period, scaling and saturation laws were formulated for concrete exposed to sulfate solution. These features have not been considered in current models used to predict life cycle of concrete exposed to aggressive environment. The mathematical analysis shows that porous concrete made with high and moderate water-to-cement ratios develops a definite scaling law after an initiation time. The scaling coefficient depends on the cement composition but does not depend on the original water-to-cement ratio. Dense concrete made with low water-to-cement ratios develops a cyclic saturation curve. An index for "potential of damage" is created to allow engineers to design concrete structures with better precision and cement chemists to develop portland cements with optimized composition.

  8. Interactions Between Serotonin Transporter Gene Haplotypes and Quality of Mothers’ Parenting Predict the Development of Children’s Noncompliance

    PubMed Central

    Sulik, Michael J.; Eisenberg, Nancy; Lemery-Chalfant, Kathryn; Spinrad, Tracy L.; Silva, Kassondra M.; Eggum, Natalie D.; Betkowski, Jennifer A.; Kupfer, Anne; Smith, Cynthia L.; Gaertner, Bridget; Stover, Daryn A.; Verrelli, Brian C.

    2012-01-01

    The LPR and STin2 polymorphisms of the serotonin transporter gene (SLC6A4) were combined into haplotypes that, together with quality of maternal parenting, were used to predict initial levels and linear change in children’s (N = 138) noncompliance and aggression from age 18 –54 months. Quality of mothers’ parenting behavior was observed when children were 18 months old, and nonparental caregivers’ reports of noncompliance and aggression were collected annually from 18 to 54 months of age. Quality of early parenting was negatively related to the slope of noncompliance only for children with the LPR-S/STin2-10 haplotype and to 18-month noncompliance only for children with haplotypes that did not include LPR-S. The findings support the notion that SLC6A4 haplotypes index differential susceptibility to variability in parenting quality, with certain haplotypes showing greater reactivity to both supportive and unsupportive environments. These different genetic backgrounds likely reflect an evolutionary response to variation in the parenting environment. PMID:22059451

  9. Korean Affairs Report.

    DTIC Science & Technology

    1985-06-06

    Urged (Editorial; Pyongyang Domestic Service, 6 May 85) 173 Kang Song-san Speaks at Designing Workers’ Meeting (KCNA, 10 May 85) 176 Kim Chong-il...missiles, short-range guided weapons, and modern chemical weapons. Such maneuvers of the U.S. imperialists and the Chon Tu-hwan ring are designed to...withdraw from South Korea, taking along all kinds of destructive weapons and aggressor military personnel, and discard their aggressive designs on our

  10. Chemical Suppression of the Reactivated Androgen Signaling Pathway in Androgen-Independent Prostate Cancer

    DTIC Science & Technology

    2012-07-01

    13. SUPPLEMENTARY NOTES 14. ABSTRACT The project studies the role of Hedgehog /Gli signaling in generating the androgen growth-independent...behavior of castration resistant prostate cancer and will test the ability of drugs that target Hedgehog or Gli as a means to suppress this behavior...advanced prostate cancer. The ultimate goal of the project is to define the mechanisms by which Hedgehog signaling molecules support aggressive

  11. A non-chemical system for online weed control.

    PubMed

    Rueda-Ayala, Victor; Peteinatos, Gerassimos; Gerhards, Roland; Andújar, Dionisio

    2015-03-30

    Non-chemical weed control methods need to be directed towards a site-specific weeding approach, in order to be able to compete the conventional herbicide equivalents. A system for online weed control was developed. It automatically adjusts the tine angle of a harrow and creates different levels of intensity: from gentle to aggressive. Two experimental plots in a maize field were harrowed with two consecutive passes. The plots presented from low to high weed infestation levels. Discriminant capabilities of an ultrasonic sensor were used to determine the crop and weed variability of the field. A controlling unit used ultrasonic readings to adjust the tine angle, producing an appropriate harrowing intensity. Thus, areas with high crop and weed densities were more aggressively harrowed, while areas with lower densities were cultivated with a gentler treatment; areas with very low densities or without weeds were not treated. Although the weed development was relatively advanced and the soil surface was hard, the weed control achieved by the system reached an average of 51% (20%-91%), without causing significant crop damage as a result of harrowing. This system is proposed as a relatively low cost, online, and real-time automatic harrow that improves the weed control efficacy, reduces energy consumption, and avoids the usage of herbicide.

  12. A Non-Chemical System for Online Weed Control

    PubMed Central

    Rueda-Ayala, Victor; Peteinatos, Gerassimos; Gerhards, Roland; Andújar, Dionisio

    2015-01-01

    Non-chemical weed control methods need to be directed towards a site-specific weeding approach, in order to be able to compete the conventional herbicide equivalents. A system for online weed control was developed. It automatically adjusts the tine angle of a harrow and creates different levels of intensity: from gentle to aggressive. Two experimental plots in a maize field were harrowed with two consecutive passes. The plots presented from low to high weed infestation levels. Discriminant capabilities of an ultrasonic sensor were used to determine the crop and weed variability of the field. A controlling unit used ultrasonic readings to adjust the tine angle, producing an appropriate harrowing intensity. Thus, areas with high crop and weed densities were more aggressively harrowed, while areas with lower densities were cultivated with a gentler treatment; areas with very low densities or without weeds were not treated. Although the weed development was relatively advanced and the soil surface was hard, the weed control achieved by the system reached an average of 51% (20%–91%), without causing significant crop damage as a result of harrowing. This system is proposed as a relatively low cost, online, and real-time automatic harrow that improves the weed control efficacy, reduces energy consumption, and avoids the usage of herbicide. PMID:25831085

  13. The Haber Bosch-harmful algal bloom (HB-HAB) link

    NASA Astrophysics Data System (ADS)

    Glibert, Patricia M.; Maranger, Roxane; Sobota, Daniel J.; Bouwman, Lex

    2014-10-01

    Large-scale commercialization of the Haber-Bosch (HB) process is resulting in intensification of nitrogen (N) fertilizer use worldwide. Globally N fertilizer use is far outpacing that of phosphorus (P) fertilizer. Much of the increase in N fertilizers is also now in the form of urea, a reduced form of N. Incorporation of these fertilizers into agricultural products is inefficient leading to significant environmental pollution and aquatic eutrophication. Of particular concern is the increased occurrence of harmful algal blooms (HABs) in waters receiving nutrient enriched runoff. Many phytoplankton causing HABs have physiological adaptive strategies that make them favored under conditions of elevated N : P conditions and supply of chemically reduced N (ammonium, urea). We propose that the HB-HAB link is a function of (1) the inefficiency of incorporation of N fertilizers in the food supply chain, the leakiness of the N cycle from crop to table, and the fate of lost N relative to P to the environment; and (2) adaptive physiology of many HABs to thrive in environments in which there is excess N relative to classic nutrient stoichiometric proportions and where chemically reduced forms of N dominate. The rate of HAB expansion is particularly pronounced in China where N fertilizer use has escalated very rapidly, where soil retention is declining, and where blooms have had large economic and ecological impacts. There, in addition to increased use of urea and high N : P based fertilizers overall, escalating aquaculture production adds to the availability of reduced forms of N, as does atmospheric deposition of ammonia. HABs in both freshwaters and marginal seas in China are highly related to these overall changing N loads and ratios. Without more aggressive N control the future outlook in terms of HABs is likely to include more events, more often, and they may also be more toxic.

  14. Corrosion Fatigue of High-Strength Titanium Alloys Under Different Stress Gradients

    NASA Astrophysics Data System (ADS)

    Baragetti, Sergio; Villa, Francesco

    2015-05-01

    Ti-6Al-4V is the most widely used high strength-to-mass ratio titanium alloy for advanced engineering components. Its adoption in the aerospace, maritime, automotive, and biomedical sectors is encouraged when highly stressed components with severe fatigue loading are designed. The extents of its applications expose the alloy to several aggressive environments, which can compromise its brilliant mechanical characteristics, leading to potentially catastrophic failures. Ti-6Al-4V stress-corrosion cracking and corrosion-fatigue sensitivity has been known since the material testing for pressurized tanks for Apollo missions, although detailed investigations on the effects of harsh environment in terms of maximum stress reduction have been not carried out until recent times. In the current work, recent experimental results from the authors' research group are presented, quantifying the effects of aggressive environments on Ti-6Al-4V under fatigue loading in terms of maximum stress reduction. R = 0.1 axial fatigue results in laboratory air, 3.5 wt.% NaCl solution, and CH3OH methanol solution at different concentrations are obtained for mild notched specimens ( K t = 1.18) at 2e5 cycles. R = 0.1 tests are also conducted in laboratory air, inert environment, 3.5 wt.% NaCl solution for smooth, mild and sharp notched specimens, with K t ranging from 1 to 18.65, highlighting the environmental effects for the different load conditions induced by the specimen geometry.

  15. Assessment of Steel Reinforcement Corrosion State by Parameters of Potentiodynamic Diagrams

    NASA Astrophysics Data System (ADS)

    Krajči, Ľudovít; Jerga, Ján

    2015-12-01

    The environment of the steel reinforcement has a significant impact on the durability and service life of a concrete structure. It is not only the presence of aggressive substances from the environment, but also the own composition of concrete mixture. The use of new types of cements, additives and admixtures must be preceded by verification, if they themselves shall not initiate the corrosion. There is a need for closer physical expression of the parameters of the potentiodynamic diagrams allowing reliable assessment of the influence of the surrounding environment on electrochemical behaviour of reinforcement. The analysis of zero retardation limits of potentiodynamic curves is presented.

  16. Characteristics of male and female prisoners involved in bullying behavior.

    PubMed

    Ireland, Jane L; Archer, John; Power, Christina L

    2007-01-01

    This study explores bullying behavior in a larger and more representative sample than previous prison-based research. It has two core aims, first to explore the nature of bullying in relation to indirect and direct aggression and, second, to explore the predictors of bully-category membership with particular reference to behavioral characteristics. Participants were adult men (n=728) and women (n=525) prisoners. All completed a behavioral measure of behavior indicative of bullying (Direct and Indirect Prisoner behavior Checklist, DIPC) that also explored prison-based behavior such as negative acts towards staff or prison rules, positive acts and drug-related behavior. Indirect aggression was, as predicted, reported more frequently than direct aggression, although this only held for perpetration. Bully-victims, as predicted, showed more negative behavior. Pure bullies and pure victims also showed more negative behavior than the other categories. The findings are discussed in relation to the environment in which bullying behavior is being assessed and with attention to the possible motivations underlying both bullying and negative behavior. Directions for future research are suggested. (c) 2007 Wiley-Liss, Inc.

  17. Genetic structure, nestmate recognition and behaviour of two cryptic species of the invasive big-headed ant Pheidole megacephala.

    PubMed

    Fournier, Denis; Tindo, Maurice; Kenne, Martin; Mbenoun Masse, Paul Serge; Van Bossche, Vanessa; De Coninck, Eliane; Aron, Serge

    2012-01-01

    Biological invasions are recognized as a major cause of biodiversity decline and have considerable impact on the economy and human health. The African big-headed ant Pheidole megacephala is considered one of the world's most harmful invasive species. To better understand its ecological and demographic features, we combined behavioural (aggression tests), chemical (quantitative and qualitative analyses of cuticular lipids) and genetic (mitochondrial divergence and polymorphism of DNA microsatellite markers) data obtained for eight populations in Cameroon. Molecular data revealed two cryptic species of P. megacephala, one inhabiting urban areas and the other rainforests. Urban populations belong to the same phylogenetic group than those introduced in Australia and in other parts of the world. Behavioural analyses show that the eight populations sampled make up four mutually aggressive supercolonies. The maximum distance between nests from the same supercolony was 49 km and the closest distance between two nests belonging to two different supercolonies was 46 m. The genetic data and chemical analyses confirmed the behavioural tests as all of the nests were correctly assigned to their supercolony. Genetic diversity appears significantly greater in Africa than in introduced populations in Australia; by contrast, urban and Australian populations are characterized by a higher chemical diversity than rainforest ones. Overall, our study shows that populations of P. megacephala in Cameroon adopt a unicolonial social structure, like invasive populations in Australia. However, the size of the supercolonies appears several orders of magnitude smaller in Africa. This implies competition between African supercolonies and explains why they persist over evolutionary time scales.

  18. Do Bumble Bee, Bombus impatiens, Queens Signal their Reproductive and Mating Status to their Workers?

    PubMed

    Amsalem, Etya; Padilla, Mario; Schreiber, Paul M; Altman, Naomi S; Hefetz, Abraham; Grozinger, Christina M

    2017-06-01

    Reproduction in social insect societies reflects a delicate balance between cooperation and conflict over offspring production, and worker reproduction is widespread even in species showing strong reproductive skew in favor of the queen. To navigate these conflicts, workers are predicted to develop the means to estimate the queen's fecundity - potentially through behavioral and/or chemical cues - and to adjust their reproduction to maximize their fitness. Here, we introduced bumble bee, Bombus impatiens, workers to queens of different mating and reproductive status and examined worker reproduction and expression levels of two genes which were previously shown to be sensitive to the presence of the queen, vitellogenin and Krüppel-homolog 1. We further explored whether the queen's chemical secretion alone is sufficient to regulate worker reproduction, aggression and gene expression. We found that worker ovary activation was inhibited only in the presence of egg-laying queens, regardless of their mating status. Workers reared in the presence of newly-mated queens showed intermediate vitellogenin expression levels relative to workers reared with mated egg-laying and virgin queens. However, none of the whole-body chemical extracts of any of the queen treatment groups affected ovary activation, aggressive behavior, or gene expression in workers. Our findings indicate that only the presence of a freely-behaving, egg-laying queen can fully inhibit worker reproduction. It remains to be determined if workers detect differences in queen mating status and fecundity through differences in the queens' behavior alone or through the queen's behavior in concert with fertility signals.

  19. Relationship Functioning Among Adult Children of Alcoholics*

    PubMed Central

    Kearns-Bodkin, Jill N.; Leonard, Kenneth E.

    2008-01-01

    Objective: The purpose of the current research was to examine the impact of both maternal and paternal alcoholism on the relationship functioning of husbands and wives over the early years of marriage. Method: Couples (N = 634) were assessed at the time of marriage, and again at their first, second, and fourth anniversaries. Husbands and wives completed separate, self-administered questionnaires at home. Results: Results of separate repeated measures analyses of covariance revealed that, for both husbands and wives, the appraisal of their marital relationship was associated with alcoholism in the opposite gender parent. That is, for husbands, alcoholism in the mother was associated with lower marital satisfaction across the 4 years of marriage. For wives, alcoholism in the father was related to lower marital intimacy. Husbands' physical aggression was influenced by mother's and father's alcoholism; high levels of physical aggression were present among men with alcoholic mothers and nonalcoholic fathers. Interestingly, wives' experience of husband's aggression was also highest among women with alcoholic mothers and nonalcoholic fathers. Wives also reported engaging in high levels of physical aggression when they had an alcoholic mother and a nonalcoholic father, but this effect was restricted to the early part of the marriage. Finally, parental alcoholism was associated with both husbands' and wives' attachment representations. Conclusions: The present findings suggest that children raised in alcoholic families may carry the problematic effects of their early family environment into their adult romantic relationships. PMID:18925353

  20. Aggression and Violence among Iranian Adolescents and Youth: A 10-year Systematic Review

    PubMed Central

    Sadeghi, Saeid; Farajzadegan, Ziba; Kelishadi, Roya; Heidari, Kamal

    2014-01-01

    Background: Although the overwhelming majority of Iranian adolescents are well-adjusted, a substantial group exhibits high levels of maladjustment and deficient functioning. Escalation of criminal violence among the youth population has become a major public policy issue and a serious public health problem. In reviewing a 10-year literature, this article aimed to describe and propose primary assumptions regarding the correlates of aggressive and violent behaviors in Iranian adolescents and youth. Methods: Bibliographic databases such as PubMed and Google Scholar along with Iranian databases including PubMed, IranMedex, Magiran, Irandoc, Psychoinfo, and Emrofor Scientific Information Database, and Magiran constituted the databases which we searched for the relevant literature. Overall 98 articles met the inclusion criteria, allowing us to initiate the discussion. Results: Reportedly, prevalence of violence and aggression among the Iranian adolescents and youth ranged from 30% to 65.5% while males being 2½ times more affected than females. The role of gender, family environment, family size, socioeconomic status, and victimization in perpetuating the circumstances was apparent. Conclusions: Relatively high prevalence of violence and aggression among Iranian youth and adolescents is a warning sign and a great challenge to the social system. Reviewed studies suffer from certain methodological and conceptual limitations. Undertaking community-based studies to estimate the actual extent of the problem is warranted. PMID:26157572

  1. Environmental concentrations of metformin exposure affect aggressive behavior in the Siamese fighting fish, Betta splendens.

    PubMed

    MacLaren, Ronald David; Wisniewski, Kathryn; MacLaren, Christina

    2018-01-01

    Metformin, the medicine most commonly prescribed for treatment of Type II diabetes, is among the most abundant pharmaceuticals being introduced into the environment. Pharmaceuticals are increasingly found in wastewater and surface waters around the world, often due to incomplete metabolism in humans and subsequent excretion in human waste. Risk analyses and exposure studies have raised concerns about potential negative impacts of pharmaceuticals at current environmental levels. Results of the present study indicate that metformin at concentrations in the range of what has been documented in freshwater systems and waste-water effluent (40 μg/L) affects aggressive behavior in adult male Betta splendens. Subjects exhibited less aggression toward a male dummy stimulus after four weeks exposure to metformin-treated water when compared to behavior measured immediately prior to their exposure, and in comparison to a separate cohort of un-exposed control fish. This effect persisted after 20 weeks exposure as well. Subjects exposed to metformin at a concentration twice that currently observed in nature (80 μg/L) exhibited an even more substantial reduction in aggressive behaviors compared to controls and pre-exposure measurements than those observed in the low-dose treatment group. Such changes in behavior have the potential to affect male fitness and possibly impact the health of natural populations of aquatic organisms exposed to the drug.

  2. Sex-specific modulation of the gut microbiome and behavior in Siberian hamsters.

    PubMed

    Sylvia, Kristyn E; Jewell, Cathleen P; Rendon, Nikki M; St John, Emma A; Demas, Gregory E

    2017-02-01

    The gut microbiome is a diverse, host-specific, and symbiotic bacterial environment that is critical for mammalian survival and exerts a surprising yet powerful influence on brain and behavior. Gut dysbiosis has been linked to a wide range of physical and psychological disorders, including autism spectrum disorders and anxiety, as well as autoimmune and inflammatory disorders. A wealth of information on the effects of dysbiosis on anxiety and depression has been reported in laboratory model systems (e.g., germ-free mice); however, the effects of microbiome disruption on social behaviors (e.g., aggression) of non-model species that may be particularly important in understanding many aspects of physiology and behavior have yet to be fully explored. Here we assessed the sex-specific effects of a broad-spectrum antibiotic on the gut microbiome and its effects on social behaviors in male and female Siberian hamsters (Phodopus sungorus). In Experiment 1, we administered a broad-spectrum antibiotic on a short-term basis and found that antibiotic treatment altered the microbial communities in the gut in male and female hamsters. In Experiment 2, we tested the effects of single versus repeated antibiotic treatment (including a recovery phase) on behavior, and found that two, but not one, treatments caused marked decreases in aggressive behavior, but not other social behaviors, in males; aggression returned to normal levels following recovery. Antibiotic-treated females, in contrast, showed decreased aggression after a single treatment, with all other social behaviors unaffected. Unlike males, female aggression did not return to normal during either recovery period. The present findings demonstrate that modest antibiotic treatment results in marked disruption of the gut microbiome in hamsters, akin to research done in other rodent species and humans. Further, we show that treatment with a broad-spectrum antibiotic, which has dysbiotic effects, also has robust, sex-specific effects on aggression, a critical behavior in the survival and reproductive success of many rodent species. Copyright © 2016 Elsevier Inc. All rights reserved.

  3. Childhood aggression and the co-occurrence of behavioural and emotional problems: results across ages 3-16 years from multiple raters in six cohorts in the EU-ACTION project.

    PubMed

    Bartels, Meike; Hendriks, Anne; Mauri, Matteo; Krapohl, Eva; Whipp, Alyce; Bolhuis, Koen; Conde, Lucia Colodro; Luningham, Justin; Fung Ip, Hill; Hagenbeek, Fiona; Roetman, Peter; Gatej, Raluca; Lamers, Audri; Nivard, Michel; van Dongen, Jenny; Lu, Yi; Middeldorp, Christel; van Beijsterveldt, Toos; Vermeiren, Robert; Hankemeijer, Thomas; Kluft, Cees; Medland, Sarah; Lundström, Sebastian; Rose, Richard; Pulkkinen, Lea; Vuoksimaa, Eero; Korhonen, Tellervo; Martin, Nicholas G; Lubke, Gitta; Finkenauer, Catrin; Fanos, Vassilios; Tiemeier, Henning; Lichtenstein, Paul; Plomin, Robert; Kaprio, Jaakko; Boomsma, Dorret I

    2018-05-29

    Childhood aggression and its resulting consequences inflict a huge burden on affected children, their relatives, teachers, peers and society as a whole. Aggression during childhood rarely occurs in isolation and is correlated with other symptoms of childhood psychopathology. In this paper, we aim to describe and improve the understanding of the co-occurrence of aggression with other forms of childhood psychopathology. We focus on the co-occurrence of aggression and other childhood behavioural and emotional problems, including other externalising problems, attention problems and anxiety-depression. The data were brought together within the EU-ACTION (Aggression in Children: unravelling gene-environment interplay to inform Treatment and InterventiON strategies) project. We analysed the co-occurrence of aggression and other childhood behavioural and emotional problems as a function of the child's age (ages 3 through 16 years), gender, the person rating the behaviour (father, mother or self) and assessment instrument. The data came from six large population-based European cohort studies from the Netherlands (2x), the UK, Finland and Sweden (2x). Multiple assessment instruments, including the Child Behaviour Checklist (CBCL), the Strengths and Difficulties Questionnaire (SDQ) and Multidimensional Peer Nomination Inventory (MPNI), were used. There was a good representation of boys and girls in each age category, with data for 30,523 3- to 4-year-olds (49.5% boys), 20,958 5- to 6-year-olds (49.6% boys), 18,291 7- to 8-year-olds (49.0% boys), 27,218 9- to 10-year-olds (49.4% boys), 18,543 12- to 13-year-olds (48.9% boys) and 10,088 15- to 16-year-olds (46.6% boys). We replicated the well-established gender differences in average aggression scores at most ages for parental ratings. The gender differences decreased with age and were not present for self-reports. Aggression co-occurred with the majority of other behavioural and social problems, from both externalising and internalising domains. At each age, the co-occurrence was particularly prevalent for aggression and oppositional and ADHD-related problems, with correlations of around 0.5 in general. Aggression also showed substantial associations with anxiety-depression and other internalizing symptoms (correlations around 0.4). Co-occurrence for self-reported problems was somewhat higher than for parental reports, but we found neither rater differences, nor differences across assessment instruments in co-occurrence patterns. There were large similarities in co-occurrence patterns across the different European countries. Finally, co-occurrence was generally stable across age and sex, and if any change was observed, it indicated stronger correlations when children grew older. We present an online tool to visualise these associations as a function of rater, gender, instrument and cohort. In addition, we present a description of the full EU-ACTION projects, its first results and the future perspectives.

  4. Data on corrosion and scaling potential of drinking water resources using stability indices in Jolfa, East Azerbaijan, Iran.

    PubMed

    Yousefi, Mahmood; Saleh, Hossein Najafi; Mahvi, Amir Hossein; Alimohammadi, Mahmood; Nabizadeh, Ramin; Mohammadi, Ali Akbar

    2018-02-01

    This cross-sectional study was conducted on the drinking water resources of the city of Jolfa (East Azerbaijan province, Iran) from samples taken from 30 wells. Calcium hardness, pH, total alkalinity, TDS, temperature and other chemical parameters were measured using standard methods. The Langelier, Rayzner, Puckhorius and aggressive indices were calculated. The results showed that the Langelier, Reynar, Puckorius, Larson-skold and aggressive indices were 1.15 (± 0.43), 6.92 (± 0.54), 6.42 (± 0.9), 0.85 (± 0.72) and 12.79 (± 0.47), respectively. In terms of water classification, 30% of samples fell into the NaCl category and 26.6% in the NaHCO 3 category and 43.4% samples in the CaHCO 3 , MgHCO 3 and MgCl category. The sedimentation indices indicated that the water of the wells could be considered as corrosive.

  5. Intrasexual competition enhances reproductive isolation between locally adapted populations

    PubMed Central

    Arias-Rodriguez, Lenin; Plath, Martin

    2018-01-01

    Abstract During adaptation to different habitat types, both morphological and behavioral traits can undergo divergent selection. Males often fight for status in dominance hierarchies and rank positions predict reproductive success. Ecotypes with reduced fighting abilities should have low reproductive success when migrating into habitats that harbor ecotypes with superior fighting abilities. Livebearing fishes in the Poecilia mexicana-species complex inhabit not only regular freshwater environments, but also independently colonized sulfidic (H2S-containing) habitats in three river drainages. In the current study, we found fighting intensities in staged contests to be considerably lower in some but not all sulfidic surface ecotypes and the sulfidic cave ecotype compared with populations from non-sulfidic surface sites. This is perhaps due to selection imposed by H2S, which hampers oxygen uptake and transport, as well as cellular respiration. Furthermore, migrants from sulfidic habitats may lose fights even if they do not show overall reduced aggressiveness, as physiological performance is likely to be challenged in the non-sulfidic environment to which they are not adapted. To test this hypothesis, we simulated migration of H2S-adapted males into H2S-free waters, as well as H2S-adapted cave-dwelling males into sulfidic surface waters. We found that intruders established dominance less often than resident males, independent of whether or not they showed reduced aggressiveness overall. Our study shows that divergent evolution of male aggressive behavior may also contribute to the maintenance of genetic differentiation in this system and we call for more careful evaluation of male fighting abilities in studies on ecological speciation. PMID:29492045

  6. Mitigating aggressiveness through education? The monoamine oxidase A genotype and mental health in general population.

    PubMed

    Kiive, Evelyn; Laas, Kariina; Akkermann, Kirsti; Comasco, Erika; Oreland, Lars; Veidebaum, Toomas; Harro, Jaanus

    2014-02-01

    Monoamine oxidase A (MAOA) gene promoter region includes a variable number of tandem repeat (VNTR) associated with antisocial behaviour in adverse environment. We have examined the effect of the MAOA-uVNTR on mental health and academic success by using a population representative sample and a longitudinal design. The data of the older cohort (n = 593, aged 15 years at the original sampling) of the longitudinal Estonian Children Personality, Behaviour and Health Study (ECPBHS) were used. Follow-ups were conducted at ages 18 and 25 years. Aggressiveness, inattention and hyperactivity were reported by class teachers or, at older age, self-reported. Stressful life events, psychological environment in the family and interactions between family members were self-reported. Data of general mental abilities and education were obtained at the age of 25, and lifetime psychiatric disorder assessment was carried out with the Mini-International Neuropsychiatric Interview (MINI) interview. MAOA-uVNTR genotype had no independent effect on aggressiveness, hyperactive and inattentive symptoms, and neither was there a genotype interaction with adverse life events. Interestingly, the proportion of male subjects with higher education by the age of 25 was significantly larger among those with MAOA low-activity alleles (χ² = 7.13; p = 0.008). Logistic regression revealed that MAOA low-activity alleles, higher mental abilities, occurrence of anxiety disorders and absence of substance-use disorder were significant independent predictors for higher education in male subjects. In a population representative sample of young subjects, the MAOA-uVNTR 'risk genotype' predicted better life outcomes as expressed in higher level of education.

  7. Ultrasonic and densimetric titration applied for acid-base reactions.

    PubMed

    Burakowski, Andrzej; Gliński, Jacek

    2014-01-01

    Classical acoustic acid-base titration was monitored using sound speed and density measurements. Plots of these parameters, as well as of the adiabatic compressibility coefficient calculated from them, exhibit changes with the volume of added titrant. Compressibility changes can be explained and quantitatively predicted theoretically in terms of Pasynski theory of non-compressible hydrates combined with that of the additivity of the hydration numbers with the amount and type of ions and molecules present in solution. It also seems that this development could be applied in chemical engineering for monitoring the course of chemical processes, since the applied experimental methods can be carried out almost independently on the medium under test (harmful, aggressive, etc.).

  8. Ants Learn Aphid Species as Mutualistic Partners: Is the Learning Behavior Species-Specific?

    PubMed

    Hayashi, Masayuki; Nakamuta, Kiyoshi; Nomura, Masashi

    2015-12-01

    In ant-aphid associations, many aphid species provide ants with honeydew and are tended by ants, whereas others are never tended and are frequently preyed upon by ants. In these relationships, ants must have the ability to discriminate among aphid species, with mutualistic aphids being accepted as partners rather than prey. Although ants reportedly use cuticular hydrocarbons (CHCs) of aphids to differentiate between mutualistic and non-mutualistic species, it is unclear whether the ability to recognize mutualistic aphid species as partners is innate or involves learning. Therefore, we tested whether aphid recognition by ants depends on learning, and whether the learning behavior is species-specific. When workers of the ant Tetramorium tsushimae had previously tended the cowpea aphid, Aphis craccivora, they were less aggressive toward this species. In addition, ants also reduced their aggressiveness toward another mutualistic aphid species, Aphis fabae, after tending A. craccivora, whereas ants remained aggressive toward the non-mutualistic aphid, Acyrthosiphon pisum, regardless of whether or not they had previous experience in tending A. craccivora. When ants were offered glass dummies treated with CHCs of these aphid species, ants that had tended A. craccivora displayed reduced aggression toward CHCs of A. craccivora and A. fabae. Chemical analyses showed the similarity of the CHC profiles between A. craccivora and A. fabae but not with A. pisum. These results suggest that aphid recognition of ants involves learning, and that the learning behavior may not be species-specific because of the similarity of CHCs between different aphid species with which they form mutualisms.

  9. Grapevine Botryosphaeria dieback fungi have specific aggressiveness factor repertory involved in wood decay and stilbene metabolization.

    PubMed

    Stempien, Elodie; Goddard, Mary-Lorène; Wilhelm, Kim; Tarnus, Céline; Bertsch, Christophe; Chong, Julie

    2017-01-01

    Grapevine trunk diseases: Eutypa dieback, esca and Botryosphaeria dieback, which incidence has increased recently, are associated with several symptoms finally leading to the plant death. In the absence of efficient treatments, these diseases are a major problem for the viticulture; however, the factors involved in disease progression are not still fully identified. In order to get a better understanding of Botryosphaeria dieback development in grapevine, we have investigated different factors involved in Botryosphaeriaceae fungi aggressiveness. We first evaluated the activity of the wood-degrading enzymes of different isolates of Neofusicoccum parvum and Diplodia seriata, two major fungi associated with Botryosphaeria dieback. We further examinated the ability of these fungi to metabolize major grapevine phytoalexins: resveratrol and δ-viniferin. Our results demonstrate that Botryosphaeriaceae were characterized by differential wood decay enzymatic activities and have the capacity to rapidly degrade stilbenes. N. parvum is able to degrade parietal polysaccharides, whereas D. seriata has a better capacity to degrade lignin. Growth of both fungi exhibited a low sensitivity to resveratrol, whereas δ-viniferin has a fungistatic effect, especially on N. parvum Bourgogne S-116. We further show that Botryosphaeriaceae are able to metabolize rapidly resveratrol and δ-viniferin. The best stilbene metabolizing activity was measured for D. seriata. In conclusion, the different Botryosphaeriaceae isolates are characterized by a specific aggressiveness repertory. Wood and phenolic compound decay enzymatic activities could enable Botryosphaeriaceae to bypass chemical and physical barriers of the grapevine plant. The specific signature of Botryosphaeriaceae aggressiveness factors could explain the importance of fungi complexes in synergistic activity in order to fully colonize the host.

  10. Chemicals, Health, Environment, and Me.

    ERIC Educational Resources Information Center

    California Univ., Berkeley. Lawrence Hall of Science.

    The CHEM (Chemicals, Health, Environment, and Me) Project is a series of 10 units designed to provide experiences for fifth and sixth graders that help them to accomplish an understanding of: (1) the nature of chemicals and how they interact with the environment; (2) how to collect, process, and analyze information; (3) how to use scientific…

  11. Implementing the dynamic appraisal of situational aggression in mental health units.

    PubMed

    Lantta, Tella; Daffern, Michael; Kontio, Raija; Välimäki, Maritta

    2015-01-01

    The aims of this study are to explain the intervention of implementing a structured violence risk assessment procedure in mental health inpatient units using the Ottawa Model of Research Use (OMRU) as a guiding framework and to consider nurses' perspectives of its clinical utility and implementation process. Patient aggression toward staff is a global concern in mental health units. The limited extant literature exploring the use of structured violence risk assessments in mental health units, although small and inconsistent, reveals some positive impacts on the incidence of aggression and staff's use of restrictive interventions. Although numerous violence risk assessment instruments have been developed and tested, their systematic implementation and use are still limited. A project titled "Safer Working Management" (111298) was conducted in a Finnish hospital district, across 3 mental health units. The 6 steps of OMRU were followed during implementation of the Dynamic Appraisal of Situational Aggression (DASA). Nurses' views toward structured violence risk assessment procedures varied. Although implementation of the DASA was seen as a useful method to increase discussions with patients and nursing staff, some staff preferred their own clinical judgment for assessment of violence risk. It is possible to use a specific model to promote the implementation of risk assessment instruments in mental health units. However, the complex mental health inpatient environment and the difficulties in understanding and managing aggressive patients present challenges for the implementation of structured violence risk assessment methods. The OMRU provides a tool for clinical nurse specialists to guide implementation process in mental health units. Clinical nurse specialists must promote training for staff regarding use of new innovations, such as the DASA. Implementation processes should be reviewed so that clinical nurse specialists can lead and support mental health staff to properly use structured violence risk assessment measures.

  12. A functional MRI study on how oxytocin affects decision making in social dilemmas: Cooperate as long as it pays off, aggress only when you think you can win.

    PubMed

    Lambert, Bruno; Declerck, Carolyn H; Boone, Christophe; Parizel, Paul M

    2017-08-01

    We investigate if the neuropeptide oxytocin (OT), known to moderate social behaviour, influences strategic decision making in social dilemmas by facilitating the integration of incentives and social cues. Participants (N=29) played two economic games with different incentive structures in the fMRI scanner after receiving OT or placebo (following a double blind, within-subject design). Pictures of angry or neutral faces (the social cues) were displayed alongside the game matrices. Consistent with a priori hypotheses based on the modulatory role of OT in mesolimbic dopaminergic brain regions, the results indicate that, compared to placebo, OT significantly increases the activation of the nucleus accumbens during an assurance (coordination) game that rewards mutual cooperation. This increases appetitive motivation so that cooperative behaviour is facilitated for risk averse individuals. OT also significantly attenuates the amygdala, thereby reducing the orienting response to social cues. The corresponding change in behaviour is only apparent in the chicken (or anti-coordination) game, where aggression is incentivized but fatal if the partner also aggresses. Because of this ambiguity, decision making can be improved by additional information, and OT steers decisions in the chicken game in accordance with the valence of the facial cue: aggress when face is neutral; retreat when it is angry. Through its combined influence on amygdala and nucleus accumbens, OT improves the selection of a cooperative or aggressive strategy in function of the best match between the incentives of the game and the social cues present in the decision environment. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. Social and Language Skills as Predictors of Bullying Roles in Early Childhood: A Narrative Summary of the Literature

    ERIC Educational Resources Information Center

    Jenkins, Lyndsay N.; Mulvey, Nichole; Floress, Margaret T.

    2017-01-01

    Despite evidence that aggressive, victim, and prosocial behaviors exist among preschool children, preschool bullying has received much less attention than school- age bullying from researchers and practitioners. Preschool is an important environment for examining social behaviors because, for many children, it is the first formal context for…

  14. Discoloration & decay in oak

    Treesearch

    Alex L. Shigo

    1971-01-01

    Diseases that result in discoloration and decay of wood are major problems affecting all species of oak. Wounds often start the processes that can lead to these diseases. The type and severity of the wound, the vigor of the tree, the environment, and the aggressiveness of microorganisms that infect are some of the most important factors that determine the nature of the...

  15. Bioclimatic models estimate areas with suitable climate for Armillaria spp. in Wyoming

    Treesearch

    James T. Blodgett; John W. Hanna; Eric W. I. Pitman; Sara M. Ashiglar; John E. Lundquist; Mee-Sook Kim; Amy L. Ross-Davis; Ned B. Klopfenstein

    2015-01-01

    Armillaria species range from beneficial saprobes to damaging root pathogens, and their ecological roles and impacts vary with environment and host. Armillaria solidipes [pending vote to conserve A. ostoyae . (Redhead et al. 2011 )] is known as an aggressive pathogen of conifers and causes tree mortality and significant growth loss in Wyoming and throughout...

  16. Predicting Family Poverty and Other Disadvantaged Conditions for Child Rearing from Childhood Aggression and Social Withdrawal: A 30-Year Longitudinal Study

    ERIC Educational Resources Information Center

    Serbin, Lisa A.; Temcheff, Caroline E.; Cooperman, Jessica M.; Stack, Dale M.; Ledingham, Jane; Schwartzman, Alex E.

    2011-01-01

    This 30-year longitudinal study examined pathways from problematic childhood behavior patterns to future disadvantaged conditions for family environment and child rearing in adulthood. Participants were mothers (n = 328) and fathers (n = 222) with lower income backgrounds participating in the ongoing Concordia Longitudinal Risk Project. Structural…

  17. The Development and Validation of the Teacher Violence Scale

    ERIC Educational Resources Information Center

    Piskin, Metin; Atik, Gökhan; Çinkir, Sakir; Ögülmüs, Selahiddin; Babadogan, Cem; Ömay Çokluk,

    2014-01-01

    Problem Statement: One of the initial tasks of the school staff is to create a safe environment, which is free of negative behaviors and role models. However, there has been a concern for the violence in the schools. Most of studies in the literature has focused on aggression, violence, and bullying among students. But, teacher violence against…

  18. Olfactory signaling of aggressive intent in male-male contests of cave crickets (Troglophilus neglectus; Orthoptera: Rhaphidophoridae)

    PubMed Central

    Žunič Kosi, Alenka

    2017-01-01

    In animal contests, communicating aggressive motivation is most often mediated by visual or acoustic signals, while chemical signals are not expected to serve such a function since they are less able to be modulated by the sender during the changing behavioral context. We describe a rare example of ephemeral olfactory signals in terrestrial animals, signals that are emitted via protrusive scent glands in male cave crickets Troglophilus neglectus (Orthoptera, Rhaphidophoridae) to reflect the state of the signaler’s aggression. We correlate the intensity of behaviorally expressed aggression of the individuals in dyadic contests with the frequency and extent of their gland tissue protrusion, the latter serving as an indication of the amount of released odor. We detected large amounts of odor release during brief gland protrusions, and the absence of its release during gland retraction. Males protruded the glands during and after encountering a rival, with the degree of protrusion increasing with the intensity of the signalers’ aggression. During the encounters, the degree of gland protrusion increased most strongly with the occurrence of the elevated body posture, directly preceding the attack. This degree was significantly higher in encounter winners than in losers displaying such posture, suggesting the highly important role of the released odor for contest resolution. After the encounters, glands were protruded almost exclusively by winners, apparently announcing victory. We tested for the function of the olfactory signals also directly, by preventing gland tissue protrusion in symmetric and asymmetric treatments of the contestants. Treating only the dominant individuals decreased the percentage of encounters they won by over 60%, while treating both contestants elicited a significant increase in the frequency and duration of fights. During contests, the olfactory signals of T. neglectus apparently function as a highly effective threat, which prevents maximal contest escalation and decreases the conflict-related costs. PMID:29112984

  19. Olfactory signaling of aggressive intent in male-male contests of cave crickets (Troglophilus neglectus; Orthoptera: Rhaphidophoridae).

    PubMed

    Stritih, Nataša; Žunič Kosi, Alenka

    2017-01-01

    In animal contests, communicating aggressive motivation is most often mediated by visual or acoustic signals, while chemical signals are not expected to serve such a function since they are less able to be modulated by the sender during the changing behavioral context. We describe a rare example of ephemeral olfactory signals in terrestrial animals, signals that are emitted via protrusive scent glands in male cave crickets Troglophilus neglectus (Orthoptera, Rhaphidophoridae) to reflect the state of the signaler's aggression. We correlate the intensity of behaviorally expressed aggression of the individuals in dyadic contests with the frequency and extent of their gland tissue protrusion, the latter serving as an indication of the amount of released odor. We detected large amounts of odor release during brief gland protrusions, and the absence of its release during gland retraction. Males protruded the glands during and after encountering a rival, with the degree of protrusion increasing with the intensity of the signalers' aggression. During the encounters, the degree of gland protrusion increased most strongly with the occurrence of the elevated body posture, directly preceding the attack. This degree was significantly higher in encounter winners than in losers displaying such posture, suggesting the highly important role of the released odor for contest resolution. After the encounters, glands were protruded almost exclusively by winners, apparently announcing victory. We tested for the function of the olfactory signals also directly, by preventing gland tissue protrusion in symmetric and asymmetric treatments of the contestants. Treating only the dominant individuals decreased the percentage of encounters they won by over 60%, while treating both contestants elicited a significant increase in the frequency and duration of fights. During contests, the olfactory signals of T. neglectus apparently function as a highly effective threat, which prevents maximal contest escalation and decreases the conflict-related costs.

  20. Association of the Ottawa Aggressive Protocol with rapid discharge of emergency department patients with recent-onset atrial fibrillation or flutter.

    PubMed

    Stiell, Ian G; Clement, Catherine M; Perry, Jeffrey J; Vaillancourt, Christian; Symington, Cheryl; Dickinson, Garth; Birnie, David; Green, Martin S

    2010-05-01

    There is no consensus on the optimal management of recent-onset episodes of atrial fibrillation or flutter. The approach to these conditions is particularly relevant in the current era of emergency department (ED) overcrowding. We sought to examine the effectiveness and safety of the Ottawa Aggressive Protocol to perform rapid cardioversion and discharge patients with these arrhythmias. This cohort study enrolled consecutive patient visits to an adult university hospital ED for recent-onset atrial fibrillation or flutter managed with the Ottawa Aggressive Protocol. The protocol includes intravenous chemical cardioversion, electrical cardioversion if necessary and discharge home from the ED. A total of 660 patient visits were included, 95.2% involving atrial fibrillation and 4.9% involving atrial flutter. The mean age of patients enrolled was 64.5 years. In total, 96.8% were discharged home and, of those, 93.3% were in sinus rhythm. All patients were initially administered intravenous procainamide, with a 58.3% conversion rate. A total of 243 patients underwent subsequent electrical cardioversion with a 91.7% success rate. Adverse events occurred in 7.6% of cases: hypotension 6.7%, bradycardia 0.3% and 7-day relapse 8.6%. There were no cases of torsades de pointes, stroke or death. The median lengths of stay in the ED were as follows: 4.9 hours overall, 3.9 hours for those undergoing conversion with procainamide and 6.5 hours for those requiring electrical conversion. This is the largest study to date to evaluate the Ottawa Aggressive Protocol, a unique approach to cardioversion for ED patients with recent-onset episodes of atrial fibrillation and flutter. Our data demonstrate that the Ottawa Aggressive Protocol is effective, safe and rapid, and has the potential to significantly reduce hospital admissions and expedite ED care.

  1. 40 CFR 372.65 - Chemicals and chemical categories to which this part applies.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 27 2010-07-01 2010-07-01 false Chemicals and chemical categories to which this part applies. 372.65 Section 372.65 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SUPERFUND, EMERGENCY PLANNING, AND COMMUNITY RIGHT-TO-KNOW PROGRAMS TOXIC CHEMICAL RELEASE REPORTING: COMMUNITY RIGHT-TO-KNOW Specifi...

  2. 40 CFR 372.65 - Chemicals and chemical categories to which this part applies.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 28 2011-07-01 2011-07-01 false Chemicals and chemical categories to which this part applies. 372.65 Section 372.65 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SUPERFUND, EMERGENCY PLANNING, AND COMMUNITY RIGHT-TO-KNOW PROGRAMS TOXIC CHEMICAL RELEASE REPORTING: COMMUNITY RIGHT-TO-KNOW Specifi...

  3. Treatment of an assaultive, sensory-impaired adolescent through a multicomponent behavioral program.

    PubMed

    Luiselli, J K

    1984-03-01

    This project examined the effects of a multicomponent behavioral treatment program on assaultive behavior in a deaf, visually-impaired adolescent boy. Two types of assaultiveness were monitored: aggression towards adults and destruction of the physical environment. Intervention consisted of a token economy system, a response cost procedure, a "relaxation" technique, and skill training sessions. Through use of a multiple baseline across behaviors design, it was demonstrated that differentially reinforcing the absence of target behaviors on a weekly basis was the crucial ingredient in the treatment package. During a maintenance programming phase, the boy was gradually weaned off the token system. At 1- and 2-year follow-ups, no aggressive or destructive acts had occurred and the boy was showing improved communication and interpersonal skills.

  4. Evolution and the psychology of intergroup conflict: the male warrior hypothesis

    PubMed Central

    McDonald, Melissa M.; Navarrete, Carlos David; Van Vugt, Mark

    2012-01-01

    The social science literature contains numerous examples of human tribalism and parochialism—the tendency to categorize individuals on the basis of their group membership, and treat ingroup members benevolently and outgroup members malevolently. We hypothesize that this tribal inclination is an adaptive response to the threat of coalitional aggression and intergroup conflict perpetrated by ‘warrior males’ in both ancestral and modern human environments. Here, we describe how male coalitional aggression could have affected the social psychologies of men and women differently and present preliminary evidence from experimental social psychological studies testing various predictions from the ‘male warrior’ hypothesis. Finally, we discuss the theoretical implications of our research for studying intergroup relations both in humans and non-humans and discuss some practical implications. PMID:22271783

  5. Optimizing temperament through litter size in short-lived, iteroparous mammals in seasonal environments.

    PubMed

    Eccard, Jana A; Rödel, Heiko G

    2011-09-01

    A number of short-lived, iteroparous animal species have small broods in the early breeding season and larger broods in later breeding season. Brood size affects not only offspring size, but as recent results suggest, may also affect offspring's temperament, hormonal status, and aggression as adults. Most populations of short-lived, iteroparous mammals fluctuate predictably over the season, with low densities in winter, increasing densities in summer and a population peak in late summer followed by a population breakdown. If animals live only through parts of the season, possibly such differences in density and hence also in social environments among seasons require different personality types to increase individual fitness. We present data on behavior of European rabbits from a field enclosure study. These data clearly show that aggressiveness is higher in young from smaller litters than in young from larger litters, and smaller litters are usually born during the early breeding season. Moreover, our data suggest that behavioral types of the young rabbits are stable over time, at least during their subadult life. We suggest, that changes in mean litter size over the course of the breeding season may not only be a product of mothers' age or food availability, but may also have an adaptive function by preparing offspring characteristics for adulthood in a social environment undergoing predictable density changes within the season. Copyright © 2011 Wiley Periodicals, Inc.

  6. Exploring consumer exposure pathways and patterns of use for chemicals in the environment through the Chemical/Product Categories Database

    EPA Pesticide Factsheets

    Exploring consumer exposure pathways and patterns of use for chemicals in the environment through the Chemical/Product Categories Database (CPCat) (Presented by: Kathie Dionisio, Sc.D., NERL, US EPA, Research Triangle Park, NC (1/23/2014).

  7. Solvents of pus-medicines with physical-chemical aggressive action

    NASA Astrophysics Data System (ADS)

    Urakov, A.; Urakova, N.; Reshetnikov, A.; Kopylov, M.; Chernova, L.

    2017-01-01

    In laboratory and clinical conditions was studied rheology of pus and sulfuric tubes after their interaction with aqueous solutions of drugs from different pharmacological groups. It is shown that solutions of almost all medicines can influence or not influence on their rheology, because local action is determined not by the name, dose or route of administration of medicines. It is established that only physical-chemical properties of fluids and physical-chemical factors of their interaction with dense pus can give them the ability to dissolve or thickening pus. We found that deliberate change physical-chemical properties of medicines solutions from various pharmacological groups, namely, raising the temperature to +42°C, increasing the alkalinity above pH 8.1 and aeration as for example by introducing carbon dioxide under pressure of 0.2 ATM, or by introducing hydrogen peroxide in 0.5 - 3%, turning them into solvents of pus, ear wax and sulfuric tubes. Discovered that solutions of drugs with such physical-chemical activity may turn thick pus and solid sulfur tube in a homogeneous liquid after a few minutes after injecting them into these biological mass.

  8. Non-Chemical Stressors in a Child's Social Environment ...

    EPA Pesticide Factsheets

    Non-chemical stressors exist in the built, natural and social environments including physical factors (e.g., noise, temperature and humidity) and psychosocial factors (e.g., poor diet, smoking, illicit drug use)[1]. Scientists study how non-chemical stressors (e.g., social support, stress, exposure to violence) from the social environment (e.g., places where children live, learn, play) affect the biological response to chemical exposures; impacting children’s health[2-5]. Poster for the 2017 CEHN Conference.

  9. 40 CFR 721.10536 - Long-chain perfluoroalkyl carboxylate chemical substances.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Long-chain perfluoroalkyl carboxylate chemical substances. 721.10536 Section 721.10536 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances §...

  10. Corrosion Behavior of AZ91D Magnesium Alloy in Three Different Physiological Environments

    NASA Astrophysics Data System (ADS)

    Zhou, Juncen; Li, Qing; Zhang, Haixiao; Chen, Funan

    2014-01-01

    Magnesium alloys have been considered as promising biomedical materials and were studied in different physiological environments. In this work, corrosion behavior of AZ91D magnesium alloy in artificial saliva, simulated body fluid (SBF), and 3.5 wt.% NaCl solution was investigated using electrochemical techniques and a short-term immersion test. In contrast with other physiological environments, the amount of aggressive ions in artificial saliva is small. In addition, a protective film is formed on the surface of samples in artificial saliva. Experimental results suggest that corrosion resistance of AZ91D magnesium alloy in artificial saliva is better than that in c-SBF and 3.5 wt.% NaCl solution.

  11. Associations Between Early Family Meal Environment Quality and Later Well-Being in School-Age Children.

    PubMed

    Harbec, Marie-Josée; Pagani, Linda S

    Past research suggests a positive link between family meals and child and adolescent health. Although researchers have often relied on how often families eat together, this may not capture the complexity of the experience. Using a birth cohort, this study examines the prospective associations between the environmental quality of the family meal experience at age 6 years and child well-being at age 10. Participants are 1492 children of the Quebec Longitudinal Study of Child Development. When children were age 6, parents reported on their typical family meal environment quality. At age 10, parents, teachers, and children themselves provided information on lifestyle habits, academic achievement, and social adjustment, respectively. The relationship between early family meal environment quality and later child outcomes was analyzed using a series of multivariate linear regression. Family meal environment quality at age 6 predicted higher levels of general fitness and lower levels of soft drink consumption, physical aggression, oppositional behavior, nonaggressive delinquency, and reactive aggression at age 10. These relationships were adjusted for child characteristics (sex, temperament problems and cognitive abilities, and baseline body mass index [BMI]) and family characteristics (family configuration and functioning, maternal education, depression, and BMI). From a population-health perspective, our findings suggest that family meals have long-term influences on children's biopsychosocial well-being. At a time when family meal frequency is on a natural decline in the population, this environmental characteristic can become a target of home-based interventions and could be featured in information campaigns that aim to optimize child development.

  12. Postincident Support for Healthcare Workers Experiencing Occupational Violence and Aggression.

    PubMed

    Shea, Tracey; Cooper, Brian; De Cieri, Helen; Sheehan, Cathy; Donohue, Ross; Lindsay, Sarah

    2018-05-10

    To investigate the relative contributions of workplace type, occupational violence and aggression (OVA) strategies and interventions along with perceptions of the occupational health and safety (OHS) environment on the likelihood of receiving postincident support following the experience of OVA. We used a cross-sectional study design with an online survey to collect data from employees in nursing and midwifery in Victoria, Australia. Survey data collected from 3,072 members of the Australian Nursing and Midwifery Federation (Victorian branch) were analyzed using logistic regression. Of the 3,072 respondents who had experienced OVA in the preceding 12 months, 1,287 (42%) reported that they had received postincident support. Hierarchical logistic regression revealed that the OHS environment was the dominant factor that predicted the likelihood of workers receiving postincident support. Working in a positive OHS environment characterized by higher levels of leading indicators of OHS, prioritization of OHS, supervisor support for safety, and team psychological safety was the stronger predictor of postincident support. Being employed in a workplace that offered training in the management and prevention of OVA also increased the likelihood of receiving postincident support. While training in the management and prevention of OVA contributed to the likelihood of receiving postincident support, a greater emphasis on the OHS environment was more important in predicting the likelihood that workers received support. This study identifies workplace practices that facilitate the provision of postincident support for healthcare workers. Facilitating effective postincident support could improve outcomes for workers, their patients and workplaces, and society in general. © 2018 Sigma Theta Tau International.

  13. Extending CO2 cryogenic aerosol cleaning for advanced optical and EUV mask cleaning

    NASA Astrophysics Data System (ADS)

    Varghese, Ivin; Bowers, Charles W.; Balooch, Mehdi

    2011-11-01

    Cryogenic CO2 aerosol cleaning being a dry, chemically-inert and residue-free process is used in the production of optical lithography masks. It is an attractive cleaning option for the mask industry to achieve the requirement for removal of all printable soft defects and repair debris down to the 50nm printability specification. In the technique, CO2 clusters are formed by sudden expansion of liquid from high to almost atmospheric pressure through an optimally designed nozzle orifice. They are then directed on to the soft defects or debris for momentum transfer and subsequent damage free removal from the mask substrate. Unlike aggressive acid based wet cleaning, there is no degradation of the mask after processing with CO2, i.e., no critical dimension (CD) change, no transmission/phase losses, or chemical residue that leads to haze formation. Therefore no restriction on number of cleaning cycles is required to be imposed, unlike other cleaning methods. CO2 aerosol cleaning has been implemented for several years as full mask final clean in production environments at several state of the art mask shops. Over the last two years our group reported successful removal of all soft defects without damage to the fragile SRAF features, zero adders (from the cleaning and handling mechanisms) down to a 50nm printability specification. In addition, CO2 aerosol cleaning is being utilized to remove debris from Post-RAVE repair of hard defects in order to achieve the goal of no printable defects. It is expected that CO2 aerosol cleaning can be extended to extreme ultraviolet (EUV) masks. In this paper, we report advances being made in nozzle design qualification for optimum snow properties (size, velocity and flux) using Phase Doppler Anemometry (PDA) technique. In addition the two new areas of focus for CO2 aerosol cleaning i.e. pellicle glue residue removal on optical masks, and ruthenium (Ru) film on EUV masks are presented. Usually, the residue left over after the pellicle has been removed from returned masks (after long term usage/exposure in the wafer fab), requires a very aggressive SPM wet clean, that drastically reduces the available budget for mask properties (CD, phase/transmission). We show that CO2aerosol cleaning can be utilized to remove the bulk of the glue residue effectively, while preserving the mask properties. This application required a differently designed nozzle to impart the required removal force for the sticky glue residue. A new nozzle was developed and qualified that resulted in PRE in the range of 92-98%. Results also include data on a patterned mask that was exposed in a lithography stepper in a wafer production environment. On EUV mask, our group has experimentally demonstrated that 50 CO2 cleaning cycles of Ru film on the EUV Front-side resulted in no appreciable reflectivity change, implying that no degradation of the Ru film occurs.

  14. The contribution of occupational factors to social inequalities in health: findings from the national French SUMER survey.

    PubMed

    Niedhammer, Isabelle; Chastang, Jean-François; David, Simone; Kelleher, Cecily

    2008-12-01

    Social inequalities in health have long been demonstrated, but the understanding of these inequalities remains unclear. Work and its related occupational factors may contribute to these inequalities. The objective of this study was to study the contribution of work factors using an integrated approach (including all types of exposures) to social inequalities in three health outcomes: poor self-reported health, long sickness absence, and work injury. Respondents were 14,241 men and 10,245 women drawn from a survey of the national French working population (response rate: 96.5%). Work factors included job characteristics, and occupational exposures of the physical, ergonomic, biological, chemical, and psychosocial work environment. All work factors were measured through expert evaluation by occupational physicians, except psychosocial work factors, which were self-reported. Strong social gradients were found for all work factors, except for psychological demands, workplace bullying, and aggression from the public. Marked social gradients were also observed for the health outcomes studied, blue collar workers being more likely to report poor self-reported health, long sickness absence, and work injury. The social differences in health were reduced strongly after adjustment for work factors (psychological demands excluded) by 24-58% according to sex and health outcomes. The strongest impacts were found for decision latitude, ergonomic, physical, and chemical exposures, as well as for work schedules. A detailed analysis allowed us to identify more precisely the contributing occupational factors. It suggests that concerted prevention of occupational risk factors would be useful not only to improve health at work, but also to reduce social inequalities in health.

  15. Investigating permeability and carbonation behavior of sustainable cements

    NASA Astrophysics Data System (ADS)

    White, C.; Blyth, A.; Scherer, G. W.; Morandeau, A. E.

    2015-12-01

    The durability of new sustainable cementitious materials is intimately linked with the ability for these materials to prevent the ingress of aggressive ions through their percolated pore networks. However, it is also important to be able to control and limit the detrimental chemical degradation mechanisms that occur to the cement binder once the ions have diffused through the pore network. Here, alkali-activated materials will be discussed, and recent research on measuring the permeability of this class of cements using the beam-bending method will be presented. It will be shown that the permeability can be controlled by tailoring the activator chemistry, and that the addition of free silica in the activator has a strong (favorable) influence on the resulting percolated pore network. Carbonation is one type of chemical degradation process that is known to severely shorten the service life of concrete, especially in environments containing elevated CO­2 levels. However, the exact atomic structural changes that occur to the main binder phase (calcium-silicate-hydrate gel) during carbonation remain largely unknown. Here, X-ray pair distribution function analysis is used to elucidate the local atomic structural changes that occur during carbonation of calcium-silicate-hydrate gel and calcium-aluminosilicate-hydrate gel (alkali-activated slag binder), where distinct differences in the extent of gel decalcification are measured according to the chemistry of the starting precursor material. The results will be discussed in the context of limiting the extent of carbonation in cementitious materials, with potential applications of alkali-activated materials in geological storage of CO2 due to their increased resistance to carbonation.

  16. [Daily practice and pulp diseases].

    PubMed

    Calmein, S; Claisse, A

    1990-09-01

    Constructive or destructive processes of pulp tissue depend on many factors: anatomic topography, particular physiology, or intensity and duration of infectious, mechanical and chemical aggression. Also irritation of the pulpo-dentinal complex induce histologic and physiologic changes. The positive diagnosis of hyperemia, acute or chronic pulpitis, pulpal necrosis and acute or chronic apical abscess is performed by clinical investigations which allow a differential diagnosis with other dental or extra-dental diseases. These multiple steps lead to an adapted and appropriate treatment.

  17. Violence. The neurologic contribution: an overview.

    PubMed

    Elliott, F A

    1992-06-01

    The role of cultural forces in either promoting or discouraging interpersonal violence is so obvious that it has been allowed to obscure the part played by biologic disorders in determining responses to endogenous and environmental challenges. Neuroscientists and clinicians have demonstrated, however, that aggression has a neuroanatomic and chemical basis, that developmental and acquired brain disorders contribute to recurrent interpersonal violence, that both biologic and sociologic factors are involved, and that to ignore either is to invite error.

  18. Prostate cancer characterization by optical contrast enhanced photoacoustics

    NASA Astrophysics Data System (ADS)

    Xu, Guan; Qin, Ming; Mukundan, Ananya; Siddiqui, Javed; Takada, Marilia; Vilar-Saavedra, Paulo; Tomlins, Scott A.; Kopelman, Raoul; Wang, Xueding

    2016-03-01

    During the past decades, prostate cancer (PCa), with an annual incident rate much higher than any other cancer, is the most commonly diagnosed cancer in American men. PCa has a relatively low progression rate yet the survival percentage decreases dramatically once the cancer has metastasized. Identifying aggressive from indolent PCa to prevent metastasis and death is critical to improving outcomes for patients with PCa. Standard procedure for assessing the aggressiveness of PCa involves the removal of tumor tissues by transrectal (TR) ultrasound (US) guided needle biopsy. The microscopic architecture of the biopsied tissue is visualized by histological or immunohistochemical staining procedures. The heterogeneity of the microscopic architecture is characterized by a Gleason score, a quantitative description of the aggressiveness of PCa. Due to the inability to identify the cancer cells, most noninvasive imaging modalities can only provide diagnosis of PCa at limited accuracy. This study investigates the feasibility of identifying PCa tumors and characterizing the aggressiveness of PCa by photoacoustic imaging assisted by cancer targeting polyacrylamide (PAA) nanoparticles (NPs). PAA is a biocompatible material used in clinics for the past 20 years. PAA NPs can protect capsulated optical contrast agents from interference by enzymes and enable prolonged systematic circulation in the living biological environment. The cancer targeting mechanism is achieved by conjugating the NPs to F3 peptides, which trace nucleolin overexpressed on the surface of cancer cells. Preliminary studies have shown that the NPs are capable of staining the PCa cells in vivo.

  19. The relation of a family history of alcoholism, obstetric complications and family environment to behavioral problems among 154 adolescents in Germany: results from the children of alcoholics study in Pomerania.

    PubMed

    Barnow, Sven; Lucht, Michael; Hamm, Alfons; John, Ulrich; Freyberger, Harald-J

    2004-01-01

    Behavioral problems in adolescence have been shown to be associated with the presence of a positive family history of alcoholism (FH+), obstetric complications (OCs), and negative parenting practices. This study tested the relation of these factors to aggression/delinquency and attention problems in an untreated population sample of 154 adolescents in Pomerania. Furthermore, we evaluated the predictive strength of a FH+, OCs and negative parenting styles in a prospective subsample of 127 adolescents using a hierarchical regression analysis. Group comparisons between offspring with higher vs. lower values on aggression/delinquency revealed that only rejection by the parents was significantly more often reported by teenagers with higher measures on these behavioral problems. Offspring with higher values on attention problems had more OCs reported by the mother and also had more feelings of parental rejection compared to controls. The results of the hierarchical regression analysis showed that parental rejection was the only significant predictor for both aggression/delinquency, and attention problems measured 1 year after the initial assessment. We conclude that parental rejection is a major risk factor for both aggression/delinquency and attention problems. Reflecting the fact that these behavioral problems have been reported to be strongly associated with later substance misuse, the improvement of parenting practices should be considered in prevention and intervention programs. Copyright 2004 S. Karger AG, Basel

  20. Racism in the form of micro aggressions and the risk of preterm birth among Black women

    PubMed Central

    Slaughter-Acey, Jaime C.; Sealy-Jefferson, Shawnita; Helmkamp, Laura; Caldwell, Cleopatra H; Osypuk, Theresa L.; Platt, Robert W.; Straughen, Jennifer K.; Dailey-Okezie, Rhonda K.; Abeysekara, Purni; Misra, Dawn P.

    2015-01-01

    Purpose This study sought to examine whether perceived interpersonal racism in the form of racial micro aggressions was associated with preterm birth (PTB) and whether the presence of depressive symptoms and perceived stress modified the association. Methods Data stem from a cohort of 1410 Black women residing in Metropolitan Detroit, Michigan enrolled into the Life-course Influences on Fetal Environments (LIFE) Study. The Daily Life Experiences of Racism and Bother (DLE-B) scale measured the frequency and perceived stressfulness of racial micro aggressions experienced during the past year. Severe past-week depressive symptomatology was measured by the Centers for Epidemiologic Studies-Depression scale (CES-D) dichotomized at ≥23. Restricted cubic splines were used to model non-linearity between perceived racism and PTB. We used the Perceived Stress Scale (PSS) to assess general stress perceptions. Results Stratified spline regression analysis demonstrated that among those with severe depressive symptoms, perceived racism was not associated with PTB. However, perceived racism was significantly associated with PTB among women with mild to moderate (CES-D score ≤22) depressive symptoms. Perceived racism was not associated with PTB among women with or without high amounts of perceived stress. Conclusions Our findings suggest that racism, at least in the form of racial micro aggressions, may not further impact a group already at high risk for PTB (those with severe depressive symptoms), but may increase the risk of PTB for women at lower baseline risk. PMID:26549132

  1. Racism in the form of micro aggressions and the risk of preterm birth among black women.

    PubMed

    Slaughter-Acey, Jaime C; Sealy-Jefferson, Shawnita; Helmkamp, Laura; Caldwell, Cleopatra H; Osypuk, Theresa L; Platt, Robert W; Straughen, Jennifer K; Dailey-Okezie, Rhonda K; Abeysekara, Purni; Misra, Dawn P

    2016-01-01

    This study sought to examine whether perceived interpersonal racism in the form of racial micro aggressions was associated with preterm birth (PTB) and whether the presence of depressive symptoms and perceived stress modified the association. Data stem from a cohort of 1410 black women residing in Metropolitan Detroit, Michigan, enrolled into the Life-course Influences on Fetal Environments (LIFE) study. The Daily Life Experiences of Racism and Bother (DLE-B) scale measured the frequency and perceived stressfulness of racial micro aggressions experienced during the past year. Severe past-week depressive symptomatology was measured by the Centers for Epidemiologic Studies-Depression scale (CES-D) dichotomized at ≥ 23. Restricted cubic splines were used to model nonlinearity between perceived racism and PTB. We used the Perceived Stress Scale to assess general stress perceptions. Stratified spline regression analysis demonstrated that among those with severe depressive symptoms, perceived racism was not associated with PTB. However, perceived racism was significantly associated with PTB among women with mild to moderate (CES-D score ≤ 22) depressive symptoms. Perceived racism was not associated with PTB among women with or without high amounts of perceived stress. Our findings suggest that racism, at least in the form of racial micro aggressions, may not further impact a group already at high risk for PTB (those with severe depressive symptoms), but may increase the risk of PTB for women at lower baseline risk. Copyright © 2016 Elsevier Inc. All rights reserved.

  2. Societies drifting apart? Behavioural, genetic and chemical differentiation between supercolonies in the yellow crazy ant Anoplolepis gracilipes.

    PubMed

    Drescher, Jochen; Blüthgen, Nico; Schmitt, Thomas; Bühler, Jana; Feldhaar, Heike

    2010-10-22

    In populations of most social insects, gene flow is maintained through mating between reproductive individuals from different colonies in periodic nuptial flights followed by dispersal of the fertilized foundresses. Some ant species, however, form large polygynous supercolonies, in which mating takes place within the maternal nest (intranidal mating) and fertilized queens disperse within or along the boundary of the supercolony, leading to supercolony growth (colony budding). As a consequence, gene flow is largely confined within supercolonies. Over time, such supercolonies may diverge genetically and, thus, also in recognition cues (cuticular hydrocarbons, CHC's) by a combination of genetic drift and accumulation of colony-specific, neutral mutations. We tested this hypothesis for six supercolonies of the invasive ant Anoplolepis gracilipes in north-east Borneo. Within supercolonies, workers from different nests tolerated each other, were closely related and showed highly similar CHC profiles. Between supercolonies, aggression ranged from tolerance to mortal encounters and was negatively correlated with relatedness and CHC profile similarity. Supercolonies were genetically and chemically distinct, with mutually aggressive supercolony pairs sharing only 33.1%±17.5% (mean ± SD) of their alleles across six microsatellite loci and 73.8%±11.6% of the compounds in their CHC profile. Moreover, the proportion of alleles that differed between supercolony pairs was positively correlated to the proportion of qualitatively different CHC compounds. These qualitatively differing CHC compounds were found across various substance classes including alkanes, alkenes and mono-, di- and trimethyl-branched alkanes. We conclude that positive feedback between genetic, chemical and behavioural traits may further enhance supercolony differentiation through genetic drift and neutral evolution, and may drive colonies towards different evolutionary pathways, possibly including speciation.

  3. An uneasy alliance: a nesting association between aggressive ants and equally fierce social wasps.

    PubMed

    Servigne, Pablo; Orivel, Jérôme; Azémar, Frédéric; Carpenter, James; Dejean, Alain; Corbara, Bruno

    2018-04-16

    Although the Neotropical territorially dominant arboreal ant Azteca chartifex Forel is very aggressive towards any intruder, its populous colonies tolerate the close presence of the fierce polistine wasp Polybia rejecta (F.). In French Guiana, 83.33% of the 48 P. rejecta nests recorded were found side by side with those of A. chartifex. This nesting association results in mutual protection from predators (i.e., the wasps protected from army ants; the ants protected from birds). We conducted field studies, laboratory-based behavioral experiments and chemical analyses to elucidate the mechanisms allowing the persistence of this association. Due to differences in the cuticular profiles of the two species, we eliminated thepossibility of chemical mimicry. Also, analyses of the carton nests did not reveal traces of marking on the envelopes. Because ant forager flows were not perturbed by extracts from the wasps' Dufour's and venom glands, we rejected any hypothetical action of repulsive chemicals. Nevertheless, we noted that the wasps 'scraped' the surface of the upper part of their nest envelope using their mandibles, likely removing the ants' scent trails, and an experiment showed that ant foragers were perturbed by the removal of their scent trails. This leads us to use the term 'erasure hypothesis'. Thus, this nesting association persists thanks to a relative tolerance by the ants towards wasp presence and the behavior of the wasps that allows them to 'contain' their associated ants through the elimination of their scent trails, direct attacks, 'wing-buzzing' behavior and ejecting the ants. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  4. Let's Play at My House: Effects of the Home Environment on the Social Behavior of Children.

    ERIC Educational Resources Information Center

    Jeffers, Victoria W.; Lore, Richard K.

    1979-01-01

    Results showed that preschool children at home initiated both more positive and aggressive social interactions and were more effective in attracting a visiting child into play than were children away from home. This was the case even when the child at home had been shyer during the first meeting of the children. (JMB)

  5. Annual Research Review: Prenatal Stress and the Origins of Psychopathology--An Evolutionary Perspective

    ERIC Educational Resources Information Center

    Glover, Vivette

    2011-01-01

    If a mother is stressed or anxious while pregnant her child is more likely to show a range of symptoms such as those of attention deficit hyperactivity disorder, conduct disorder, aggression or anxiety. While there remains some debate about what proportion of these effects are due to the prenatal or the postnatal environment, and the role of…

  6. Arresting Development: Zero Tolerance and the Criminalization of Children

    ERIC Educational Resources Information Center

    Fuentes, Annette

    2012-01-01

    Supposedly designed to improve student attendance, the aggressive truancy policing in Los Angeles (LA) has discouraged students from going to class and often pushes them to drop out and into harm's way. Truancy tickets play a role in the school-to-prison pipeline. Students are being brought up in an environment that is a pre-prisoning of youth. LA…

  7. Violent Youths' Responses to High Levels of Exposure to Community Violence: What Violent Events Reveal about Youth Violence

    ERIC Educational Resources Information Center

    Wilkinson, Deanna L.; Carr, Patrick J.

    2008-01-01

    Recent work on the relationship between adolescent violence and its outcomes has posited that aggression by adolescents who are exposed to violence can be viewed as an adaptive strategy that seeks to order dangerous and unpredictable environments. Using reports from 416 active violent youth, we analyze lifetime exposure to community violence and…

  8. Effect of anti-glycolytic agents on tumour cells in vitro

    NASA Astrophysics Data System (ADS)

    Korshunov, D. A.; Kondakova, I. V.

    2016-08-01

    A metabolic change is one of the tumour hallmarks, which has recently attracted a great amount of attention. One of the main metabolic characteristics of tumour cells is a high level of glycolysis even in the presence of oxygen, known as aerobic glycolysis or the Warburg effect. The energy production is much less in a glycolysis pathway than that in a tricarboxylic acid cycle. The Warburg effect constitutes a fundamental adaptation of tumour cells to a relatively hostile environment, and supports the evolution of aggressive and metastatic phenotypes. As a result, tumour glycolysis may become an attractive target for cancer therapy. Here, we research the effect of potential anticancer agents on tumour cells in vitro. In our study, we found a high sensitivity of tumour cells to anti-glycolityc drugs. In addition, tumour cells are more resistant to the agents studied in comparison with normal cells. We also observed an atypical cooperative interaction of tumour cells in the median lethal dose of drugs. They formed the specific morphological structure of the surviving cells. This behavior is not natural for the culture of tumour cells. Perhaps this is one of the mechanisms of cells' adaptation to the aggressive environment.

  9. [Violence by and against people with mental illnesses].

    PubMed

    Steinert, Tilman; Traub, Hans-Joachim

    2016-01-01

    There is robust evidence for an increased risk of violence through people with psychotic disorders. Until recently this was frequently denied to prevent stigmatization. Alcohol and drug abuse equally increases the risk, while appropriate treatment reduces it drastically. Staff in psychiatric hospitals is exposed to an elevated risk of aggressive assaults. A limited number of severely ill and socially disintegrated patients accounts for these incidents, which are often recurrent. Besides patient characteristics, factors such as ward climate, staffing levels, education and attitudes of staff, and physical environment play a major role in aggressive escalations. On the other hand, mentally ill people, particularly women, are themselves at a higher risk of becoming victims of violent and non-violent crime. This also applies after correction for variables such as social status and living environment. Additionally mentally ill people are confronted with violence in the form of coercive interventions legitimised by the state (involuntary admission, involuntary treatment, freedom-restrictive measures such as seclusion or manual/physical restraint). In contrast to other countries in Central and Western Europe, involuntary outpatient treatment has never been legalized in Germany. Efforts to reduce violence and coercion in psychiatric facilities by evidence-based interventions are widespread nowadays, treatment guidelines are available.

  10. Negative phenotypic and genetic correlation between natal dispersal propensity and nest-defence behaviour in a wild bird.

    PubMed

    Bize, Pierre; Daniel, Grégory; Viblanc, Vincent A; Martin, Julien G A; Doligez, Blandine

    2017-07-01

    Natural selection is expected to favour the integration of dispersal and phenotypic traits allowing individuals to reduce dispersal costs. Accordingly, associations have been found between dispersal and personality traits such as aggressiveness and exploration, which may facilitate settlement in a novel environment. However, the determinism of these associations has only rarely been explored. Here, we highlight the functional integration of individual personality in nest-defence behaviour and natal dispersal propensity in a long-lived colonial bird, the Alpine swift ( Apus melba ), providing insights into genetic constraints shaping the coevolution of these two traits. We report a negative association between natal dispersal and nest-defence (i.e. risk taking) behaviour at both the phenotypic and genetic level. This negative association may result from direct selection if risk-averseness benefits natal dispersers by reducing the costs of settlement in an unfamiliar environment, or from indirect selection if individuals with lower levels of nest defence also show lower levels of aggressiveness, reducing costs of settlement among unfamiliar neighbours in a colony. In both cases, these results highlight that risk taking is an important behavioural trait to consider in the study of dispersal evolution. © 2017 The Author(s).

  11. Transport and transportation pathways of hazardous chemicals from solid waste disposal.

    PubMed Central

    Van Hook, R I

    1978-01-01

    To evaluate the impact of hazardous chemicals in solid wastes on man and other organisms, it is necessary to have information about amounts of chemical present, extent of exposure, and chemical toxicity. This paper addresses the question of organism exposure by considering the major physical and biological transport pathways and the physicochemical and biochemical transformations that may occur in sediments, soils, and water. Disposal of solid wastes in both terrestrial and oceanic environments is considered. Atmospheric transport is considered for emissions from incineration of solid wastes and for wind resuspension of particulates from surface waste deposits. Solid wastes deposited in terrestrial environments are subject to leaching by surface and ground waters. Leachates may then be transported to other surface waters and drinking water aquifers through hydrologic transport. Leachates also interact with natural organic matter, clays, and microorganisms in soils and sediments. These interactions may render chemical constituents in leachates more or less mobile, possibly change chemical and physical forms, and alter their biological activity. Oceanic waste disposal practices result in migration through diffusion and ocean currents. Surface area-to-volume ratios play a major role in the initial distributions of chemicals in the aquatic environment. Sediments serve as major sources and sinks of chemical contaminants. Food chain transport in both aquatic and terrestrial environments results in the movement of hazardous chemicals from lower to higher positions in the food web. Bioconcentration is observed in both terrestrial and aquatic food chains with certain elements and synthetic organics. Bioconcentration factors tend to be higher for synthetic organics, and higher in aquatic than in terrestrial systems. Biodilution is not atypical in terrestrial environments. Synergistic and antagonistic actions are common occurrences among chemical contaminants and can be particularly important toxicity considerations in aquatic environments receiving runoff from several terrestrial sources. PMID:367772

  12. Ecological Assembly of Chemical Mixtures

    EPA Science Inventory

    Human-environment interactions have a significant role in the formation of chemical mixtures in the environment and by extension in human tissues and fluids. These interactions, which include decisions to purchase and use products containing chemicals as well as behaviors and act...

  13. Radiology system evolution in the new millennium.

    PubMed

    Nauert, R C

    2001-01-01

    For many decades the practice of radiology grew slowly in America and was largely a secondary function under the control of hospitals. In more recent times it has vastly expanded its array of diagnostic, interventional, and therapeutic abilities. There is increasing consumer logic for direct access. Motivations have grown to create large independent entities with broadly diverse capabilities in order to succeed in the new millennium. Most regional markets are evolving rapidly in terms of managed care penetration, health system formation, physician practice consolidation and aggressive purchaser behavior by employers and consumers. To understand the enormity of healthcare evolution, it is useful to look at the industry's paradigm shifts in recent decades. Virtually every aspect of organizational infrastructure, delivery approaches, and the business environment has evolved markedly during the past fifty years. These changes will accelerate. To succeed financially, radiology groups must strengthen their market positions, technical capabilities, continuums of care and geographic dominance. Equally important is the wisdom of diversifying incomes into related services and businesses that provide additional related revenues. Key factors for successful development include facility market growth, full coverage of managed care contracts, high efficiency and aggressive diversification. A fully evolved system generates significant revenues and profitability by protecting and strengthening its financial position in this environment. That is accomplished through the development of strategically located radiology groups, aggressive alliances with medical practices in allied disciplines, and managed radiology departments and facilities for partner health systems. Organizational success ultimately depends on the ability to accept capitated payments under risk-bearing arrangements. The strategic business plan should be organized with the appropriate levels of detail needed to establish executive focus and priorities. These should be woven into operational and capital budgets to reflect expectations of the revenues, expenses and investments tied to the plan. While formidable, all of these objectives are realistic and can be accomplished if the right decisions are made. Initially, the entity's principle business objective is to formulate and begin implementation of methodical yet aggressive strategies for growth that are sensitive to sustaining high levels of quality patient care. The next phase features mergers with large, independent radiology practices in key geographic areas and successful acquisition of smaller practices. The objective of the final phase is to aggressively expand into select metropolitan areas with regional coverage and full teleradiology capabilities. High levels of market strength and financial performance are necessary to succeed. Passive limitations to small geographic areas and narrow practices will undermine their market position and dissolve financial strength with no hope of recovery. Only the dominant systems will survive and prosper.

  14. Perceiving classroom aggression: the influence of setting, intervention style and group perceptions.

    PubMed

    Lawrence, Claire; Green, Karen

    2005-12-01

    Violence and aggression in the classroom are often cited as a major concern within the teaching community. Teachers' perceptions of the appropriateness of intervention behaviours during aggressive incidents, however, are less often examined (Meyer, Astor, & Behre, 2002), nor how they compare to the perceptions of training teachers (John, 2002). This paper examines differences in the perceptions of practising and training teachers after exposure to an account of a violent incident where a school teacher is assaulted. The paper also investigates the relative and combined influence of classroom condition and teacher intervention on perceptions of classroom violence. Participants included 48 practising teachers, and 48 students undertaking a Postgraduate Certificate in Education (PGCE) also took part in the study. The study utilized a 2 x 2 x 2 between-subjects factorial design, manipulating the impact of classroom condition, teacher intervention, and observer status on evaluations of the teacher, assailant and school following an incident of violence against the teacher. Classroom environment, teacher intervention, and observer status influenced evaluations of the teacher and school, but not the assailant. Implications of these findings and the applied importance of these results are discussed in relation to school policy, teacher training, and classroom maintenance.

  15. Relationship management strategies for daughters in conflicted relationships with their ageing mothers.

    PubMed

    Pickering, Carolyn E Z; Moon, Ailee; Pieters, Huibrie C; Mentes, Janet C; Phillips, Linda R

    2015-03-01

    To study relationship management strategies of daughters in conflicted relationships with their mothers and how they promoted or prevented elder abuse. Daughters have enduring, unique relationships with their mothers that often carry over into caregiving. Pre-caregiving relationship quality is related to many caregiving outcomes, although it is unclear how. Qualitative study. Grounded theory design, informed by feminism, with telephone interviews conducted between January 2013-July 2013. The sample (N = 13) was recruited through an online recruitment strategy, with advertisements posted on relevant websites asking 'Are you in an abusive relationship with your ageing mother?' Daughters used coping strategies and self-protective strategies aimed at decreasing their exposure to aggression and emotional distress when interacting with their ageing mothers. Daughters also used spiteful aggression out of the desire for revenge. Although the daughters' strategies served their personal needs, they jeopardized the mothers' needs by creating an environment where neglect could occur. Daughters also readily and intentionally used aggression against their mothers. These were strategies daughters have found useful. These strategies may be potential areas for designing interventions to promote healthy family relationships and decrease the occurrence of elder abuse and neglect. © 2014 John Wiley & Sons Ltd.

  16. Temperature-specific competition between invasive mosquitofish and an endangered cyprinodontid fish.

    PubMed

    Carmona-Catot, Gerard; Magellan, Kit; García-Berthou, Emili

    2013-01-01

    Condition-specific competition is widespread in nature. Species inhabiting heterogeneous environments tend to differ in competitive abilities depending on environmental stressors. Interactions between these factors can allow coexistence of competing species, which may be particularly important between invasive and native species. Here, we examine the effects of temperature on competitive interactions between invasive mosquitofish, Gambusia holbrooki, and an endemic Iberian toothcarp, Aphanius iberus. We compare the tendency to approach heterospecifics and food capture rates between these two species, and examine differences between sexes and species in aggressive interactions, at three different temperatures (19, 24 and 29°C) in three laboratory experiments. Mosquitofish exhibit much more aggression than toothcarp. We show that mosquitofish have the capacity to competitively displace toothcarp through interference competition and this outcome is more likely at higher temperatures. We also show a reversal in the competitive hierarchy through reduced food capture rate by mosquitofish at lower temperatures and suggest that these two types of competition may act synergistically to deprive toothcarp of food at higher temperatures. Males of both species carry out more overtly aggressive acts than females, which is probably related to the marked sexual dimorphism and associated mating systems of these two species. Mosquitofish may thus impact heavily on toothcarp, and competition from mosquitofish, especially in warmer summer months, may lead to changes in abundance of the native species and displacement to non-preferred habitats. Globally increasing temperatures mean that highly invasive, warm-water mosquitofish may be able to colonize environments from which they are currently excluded through reduced physiological tolerance to low temperatures. Research into the effects of temperature on interactions between native and invasive species is thus of fundamental importance.

  17. Temperature-Specific Competition between Invasive Mosquitofish and an Endangered Cyprinodontid Fish

    PubMed Central

    Carmona-Catot, Gerard; Magellan, Kit; García-Berthou, Emili

    2013-01-01

    Condition-specific competition is widespread in nature. Species inhabiting heterogeneous environments tend to differ in competitive abilities depending on environmental stressors. Interactions between these factors can allow coexistence of competing species, which may be particularly important between invasive and native species. Here, we examine the effects of temperature on competitive interactions between invasive mosquitofish, Gambusia holbrooki, and an endemic Iberian toothcarp, Aphanius iberus. We compare the tendency to approach heterospecifics and food capture rates between these two species, and examine differences between sexes and species in aggressive interactions, at three different temperatures (19, 24 and 29°C) in three laboratory experiments. Mosquitofish exhibit much more aggression than toothcarp. We show that mosquitofish have the capacity to competitively displace toothcarp through interference competition and this outcome is more likely at higher temperatures. We also show a reversal in the competitive hierarchy through reduced food capture rate by mosquitofish at lower temperatures and suggest that these two types of competition may act synergistically to deprive toothcarp of food at higher temperatures. Males of both species carry out more overtly aggressive acts than females, which is probably related to the marked sexual dimorphism and associated mating systems of these two species. Mosquitofish may thus impact heavily on toothcarp, and competition from mosquitofish, especially in warmer summer months, may lead to changes in abundance of the native species and displacement to non-preferred habitats. Globally increasing temperatures mean that highly invasive, warm-water mosquitofish may be able to colonize environments from which they are currently excluded through reduced physiological tolerance to low temperatures. Research into the effects of temperature on interactions between native and invasive species is thus of fundamental importance. PMID:23382951

  18. Technologies to Combat Weapons of Mass Destruction

    DTIC Science & Technology

    2008-03-12

    performance standards across our agencies and our operations, and toxic industrial chemicals and the unique atmospheric condi- tions in an urban environment... chlorine cylinders in improvised explosive devices. While to date these types of attacks have killed fewer people than conventional sui- cide bombs, it...environment include a broad array of chemicals, to include toxic industrial chemicals. The urban environment also has very localized atmospheric

  19. Occupational hazards in hospitals: accidents, radiation, exposure to noxious chemicals, drug addiction and psychic problems, and assault.

    PubMed Central

    Gestal, J J

    1987-01-01

    Except for infectious diseases all the main occupational hazards affecting health workers are reviewed: accidents (explosions, fires, electrical accidents, and other sources of injury); radiation (stochastic and non-stochastic effects, protective measures, and personnel most at risk); exposure to noxious chemicals, whose effects may be either local (allergic eczema) or generalised (cancer, mutations), particular attention being paid to the hazards presented by formol, ethylene oxide, cytostatics, and anaesthetic gases; drug addiction (which is more common among health workers than the general population) and psychic problems associated with promotion, shift work, and emotional stress; and assault (various types of assault suffered by health workers, its causes, and the characterisation of the most aggressive patients). PMID:3307896

  20. Grapevine Botryosphaeria dieback fungi have specific aggressiveness factor repertory involved in wood decay and stilbene metabolization

    PubMed Central

    Wilhelm, Kim; Tarnus, Céline; Bertsch, Christophe

    2017-01-01

    Grapevine trunk diseases: Eutypa dieback, esca and Botryosphaeria dieback, which incidence has increased recently, are associated with several symptoms finally leading to the plant death. In the absence of efficient treatments, these diseases are a major problem for the viticulture; however, the factors involved in disease progression are not still fully identified. In order to get a better understanding of Botryosphaeria dieback development in grapevine, we have investigated different factors involved in Botryosphaeriaceae fungi aggressiveness. We first evaluated the activity of the wood-degrading enzymes of different isolates of Neofusicoccum parvum and Diplodia seriata, two major fungi associated with Botryosphaeria dieback. We further examinated the ability of these fungi to metabolize major grapevine phytoalexins: resveratrol and δ-viniferin. Our results demonstrate that Botryosphaeriaceae were characterized by differential wood decay enzymatic activities and have the capacity to rapidly degrade stilbenes. N. parvum is able to degrade parietal polysaccharides, whereas D. seriata has a better capacity to degrade lignin. Growth of both fungi exhibited a low sensitivity to resveratrol, whereas δ-viniferin has a fungistatic effect, especially on N. parvum Bourgogne S-116. We further show that Botryosphaeriaceae are able to metabolize rapidly resveratrol and δ-viniferin. The best stilbene metabolizing activity was measured for D. seriata. In conclusion, the different Botryosphaeriaceae isolates are characterized by a specific aggressiveness repertory. Wood and phenolic compound decay enzymatic activities could enable Botryosphaeriaceae to bypass chemical and physical barriers of the grapevine plant. The specific signature of Botryosphaeriaceae aggressiveness factors could explain the importance of fungi complexes in synergistic activity in order to fully colonize the host. PMID:29261692

  1. In vivo detection of acute intracellular acidification in glioblastoma multiforme following a single dose of cariporide.

    PubMed

    Albatany, Mohammed; Li, Alex; Meakin, Susan; Bartha, Robert

    2018-05-10

    Glioblastoma is an aggressive brain cancer that is very difficult to treat. Clinically, it is important to be able to distinguish aggressive from non-aggressive brain tumors. Previous studies have shown that some drugs can induce a rapid change in intracellular pH that could help to identify aggressive cancer. The sodium proton exchanger (NHE1) plays a significant role in maintaining pH balance in the tumor microenvironment. Cariporide is a sodium proton exchange inhibitor that is well tolerated by humans in cardiac applications. We hypothesized that cariporide could selectively acidify brain tumors. The purpose of this study was to determine whether amine/amide concentration-independent detection (AACID) chemical exchange saturation transfer (CEST) MRI measurement of tumor pH i could detect acidification after cariporide injection. Using a 9.4T MRI scanner, CEST spectra were acquired in six mice approximately 14 days after implanting 10 5 U87 human glioblastoma multiforme cells in the brain, before and after administration of cariporide (dose: 6 mg/kg) by intraperitoneal injection. Three additional mice were studied as controls and received only vehicle injection (DMSO + PBS). Repeated measures t test was used to examine changes in tumor and contralateral tissue regions of interest. Two hours after cariporide injection, there was a significant 0.12 ± 0.03 increase in tumor AACID value corresponding to a 0.48 decrease in pH i and no change in AACID value in contralateral tissue. A small but significant increase of 0.04 ± 0.017 in tumor AACID value was also observed following vehicle injection. This study demonstrates that acute CEST MRI contrast changes, indicative of intracellular acidification, after administration of cariporide could help localize glioblastoma.

  2. Social context influences chemical communication in D. melanogaster males.

    PubMed

    Kent, Clement; Azanchi, Reza; Smith, Ben; Formosa, Amanda; Levine, Joel D

    2008-09-23

    Chemical communication mediates social interactions in insects. For the fruit fly, D. melanogaster, the chemical display is a key fitness trait because it leads to mating. An exchange of cues that resembles a dialogue between males and females is enacted by pheromones, chemical signals that pass between individual flies to alter physiology and behavior. Chemical signals also affect the timing of locomotor activity and sleep. We investigated genetic and environmental determinants of chemical communication. To evaluate the role of the social environment, we extracted a chemical blend from individual males selected from groups composed of one genotype and compared these extracts to those from groups of mixed genotypes. To evaluate the role of the physical environment, these comparisons were performed under a light-dark cycle or in constant darkness. Here, we show that chemical signaling is affected by the social environment, light-dark cycle, and genotype as well as the complex interplay of these variables. Gene-by-environment interactions produce highly significant effects on chemical signaling. We also examined individual responses within the groups. Strikingly, the response of one wild-type fly to another is modulated by the genotypic composition of his neighbors. Chemical signaling in D. melanogaster may be a "fickle" trait that depends on the individual's social background.

  3. Method for detection of selected chemicals in an open environment

    NASA Technical Reports Server (NTRS)

    Duong, Tuan (Inventor); Ryan, Margaret (Inventor)

    2009-01-01

    The present invention relates to a space-invariant independent component analysis and electronic nose for detection of selective chemicals in an unknown environment, and more specifically, an approach to analysis of sensor responses to mixtures of unknown chemicals by an electronic nose in an open and changing environment. It is intended to fill the gap between an alarm, which has little or no ability to distinguish among chemical compounds causing a response, and an analytical instrument, which can distinguish all compounds present but with no real-time or continuous event monitoring ability.

  4. Cruel intentions on television and in real life: can viewing indirect aggression increase viewers' subsequent indirect aggression?

    PubMed

    Coyne, Sarah M; Archer, John; Eslea, Mike

    2004-07-01

    Numerous studies have shown that viewing violence in the media can influence an individual's subsequent aggression, but none have examined the effect of viewing indirect aggression. This study examines the immediate effect of viewing indirect and direct aggression on subsequent indirect aggression among 199 children ages 11 to 14 years. They were shown an indirect, direct, or no-aggression video and their subsequent indirect aggression was measured by negative evaluation of a confederate and responses to a vignette. Participants viewing indirect or direct aggression gave a more negative evaluation of and less money to a confederate than participants viewing no-aggression. Participants viewing indirect aggression gave less money to the confederate than those viewing direct aggression. Participants viewing indirect aggression gave more indirectly aggressive responses to an ambiguous situation and participants viewing direct aggression gave more directly aggressive responses. This study provides the first evidence that viewing indirect aggression in the media can have an immediate impact on subsequent aggression.

  5. 40 CFR 761.253 - Chemical analysis.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Chemical analysis. 761.253 Section 761.253 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT... Sample Sites, Collecting Surface Samples, and Analyzing Standard PCB Wipe Samples § 761.253 Chemical...

  6. 40 CFR 761.253 - Chemical analysis.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Chemical analysis. 761.253 Section 761.253 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT... Sample Sites, Collecting Surface Samples, and Analyzing Standard PCB Wipe Samples § 761.253 Chemical...

  7. 40 CFR 761.253 - Chemical analysis.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Chemical analysis. 761.253 Section 761.253 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT... Sample Sites, Collecting Surface Samples, and Analyzing Standard PCB Wipe Samples § 761.253 Chemical...

  8. 40 CFR 761.253 - Chemical analysis.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Chemical analysis. 761.253 Section 761.253 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT... Sample Sites, Collecting Surface Samples, and Analyzing Standard PCB Wipe Samples § 761.253 Chemical...

  9. 40 CFR 761.253 - Chemical analysis.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Chemical analysis. 761.253 Section 761.253 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT... Sample Sites, Collecting Surface Samples, and Analyzing Standard PCB Wipe Samples § 761.253 Chemical...

  10. Non-Chemical Stressors in a Child’s Social Environment

    EPA Science Inventory

    Non-chemical stressors exist in the built, natural and social environments including physical factors (e.g., noise, temperature and humidity) and psychosocial factors (e.g., poor diet, smoking, illicit drug use)[1]. Scientists study how non-chemical stressors (e.g., social suppor...

  11. Changes in Aggressiveness of the Ascochyta lentis Population in Southern Australia

    PubMed Central

    Davidson, Jennifer; Smetham, Gabriel; Russ, Michelle H.; McMurray, Larn; Rodda, Matthew; Krysinska-Kaczmarek, Marzena; Ford, Rebecca

    2016-01-01

    Anecdotal evidence identified a change in the reaction of the resistant lentil cv Nipper to ascochyta blight in South Australia in 2010 and subsequent seasons, leading to infection. This study investigated field reactions of lentil cultivars against Ascochyta lentis and the pathogenic variability of the A. lentis population in southern Australia on commonly grown cultivars and on parental germplasm used in the Australian lentil breeding program. Disease data recorded in agronomic and plant breeder field trials from 2005 to 2014 in southern Australia confirmed the change in reaction on the foliage of the previously resistant cvs Nipper and Northfield. Cultivar responses to seed staining from A. lentis did not change. The change in foliar response was confirmed in a series of controlled environment experiments using single, conidium-derived, isolates of A. lentis collected over different years and inoculated onto differential host sets. Specific isolate/cultivar interactions produced a significant range of disease reactions from high to low aggressiveness with a greater percentage of isolates more aggressive on cvs Nipper, Northfield and PBA Flash than previously detected. Specific isolates were tested against Australian lentil cultivars and breeding lines in controlled conditions, again verifying the aggressiveness on cv Nipper. A small percentage of isolates collected prior to the commercial release of cv Nipper were also able to infect this cultivar indicating a natural variability of the A. lentis population which subsequently may have been selected in response to high cropping intensity of cv Nipper. Spore release studies from naturally infested lentil stubbles collected from commercial crops also resulted in a high percentage of infection on the previously resistant cvs Nipper and Northfield. Less than 10% of the lesions developed on the resistant differentials ILL7537 and cv Indianhead. Pathogenic variation within the seasonal populations was not affected by the cultivar from which the stubble was sourced, further indicating a natural variability in aggressiveness. The impact of dominant cultivars in cropping systems and loss of effective disease resistance is discussed. Future studies are needed to determine if levels of aggressiveness among A. lentis isolates are increasing against a range of elite cultivars. PMID:27065073

  12. Effect of chemical environment and rock composition on fracture mechanics properties of reservoir lithologies in context of CO2 sequestration

    NASA Astrophysics Data System (ADS)

    Major, J. R.; Eichhubl, P.; Callahan, O. A.

    2015-12-01

    The coupled chemical and mechanical response of reservoir and seal rocks to injection of CO2 have major implications on the short and long term security of sequestered carbon. Many current numerical models evaluating behavior of reservoirs and seals during and after CO2 injection in the subsurface consider chemistry and mechanics separately and use only simple mechanical stability criteria while ignoring time-dependent failure parameters. CO2 injection irreversibly alters the subsurface chemical environment which can then affect geomechanical properties on a range of time scales by altering rock mineralogy and cements through dissolution, remobilization, and precipitation. It has also been documented that geomechanical parameters such as fracture toughness (KIC) and subcritical index (SCI) are sensitive to chemical environment. Double torsion fracture mechanics testing of reservoir lithologies under controlled environmental conditions relevant to CO2 sequestration show that chemical environment can measurably affect KIC and SCI. This coupled chemical-mechanical behavior is also influenced by rock composition, grains, amount and types of cement, and fabric. Fracture mechanics testing of the Aztec Sandstone, a largely silica-cemented, subarkose sandstone demonstrate it is less sensitive to chemical environment than Entrada Sandstone, a silty, clay-rich sandstone. The presence of de-ionized water lowers KIC by approximately 20% and SCI 30% in the Aztec Sandstone relative to tests performed in air, whereas the Entrada Sandstone shows reductions on the order of 70% and 90%, respectively. These results indicate that rock composition influences the chemical-mechanical response to deformation, and that the relative chemical reactivity of target reservoirs should be recognized in context of CO2 sequestration. In general, inert grains and cements such as quartz will be less sensitive to the changing subsurface environment than carbonates and clays.

  13. Identifying cognitive predictors of reactive and proactive aggression.

    PubMed

    Brugman, Suzanne; Lobbestael, Jill; Arntz, Arnoud; Cima, Maaike; Schuhmann, Teresa; Dambacher, Franziska; Sack, Alexander T

    2015-01-01

    The aim of this study was to identify implicit cognitive predictors of aggressive behavior. Specifically, the predictive value of an attentional bias for aggressive stimuli and automatic association of the self and aggression was examined for reactive and proactive aggressive behavior in a non-clinical sample (N = 90). An Emotional Stroop Task was used to measure an attentional bias. With an idiographic Single-Target Implicit Association Test, automatic associations were assessed between words referring to the self (e.g., the participants' name) and words referring to aggression (e.g., fighting). The Taylor Aggression Paradigm (TAP) was used to measure reactive and proactive aggressive behavior. Furthermore, self-reported aggressiveness was assessed with the Reactive Proactive Aggression Questionnaire (RPQ). Results showed that heightened attentional interference for aggressive words significantly predicted more reactive aggression, while lower attentional bias towards aggressive words predicted higher levels of proactive aggression. A stronger self-aggression association resulted in more proactive aggression, but not reactive aggression. Self-reports on aggression did not additionally predict behavioral aggression. This implies that the cognitive tests employed in our study have the potential to discriminate between reactive and proactive aggression. Aggr. Behav. 41:51-64 2015. © 2014 Wiley Periodicals, Inc. © 2014 Wiley Periodicals, Inc.

  14. Laboratory Studies on the Formation of Carbon-Bearing Molecules in Extraterrestrial Environments: From the Gas Phase to the Solid State

    NASA Technical Reports Server (NTRS)

    Jamieson, C. S.; Guo, Y.; Gu, X.; Zhang, F.; Bennett, C. J.; Kaiser, R. I.

    2006-01-01

    A detailed knowledge of the formation of carbon-bearing molecules in interstellar ices and in the gas phase of the interstellar medium is of paramount interest to understand the astrochemical evolution of extraterrestrial environments (1). This research also holds strong implications to comprehend the chemical processing of Solar System environments such as icy planets and their moons together with the atmospheres of planets and their satellites (2). Since the present composition of each interstellar and Solar System environment reflects the matter from which it was formed and the processes which have changed the chemical nature since the origin (solar wind, planetary magnetospheres, cosmic ray exposure, photolysis, chemical reactions), a detailed investigation of the physicochemical mechanisms altering the pristine environment is of paramount importance to grasp the contemporary composition. Once these underlying processes have been unraveled, we can identify those molecules, which belonged to the nascent setting, distinguish molecular species synthesized in a later stage, and predict the imminent chemical evolution of, for instance, molecular clouds. Laboratory experiments under controlled physicochemical conditions (temperature, pressure, chemical composition, high energy components) present ideal tools for simulating the chemical evolution of interstellar and Solar System environments. Here, laboratory experiments can predict where and how (reaction mechanisms; chemicals necessary) in extraterrestrial environments and in the interstellar medium complex, carbon bearing molecules can be formed on interstellar grains and in the gas phase. This paper overviews the experimental setups utilized in our laboratory to mimic the chemical processing of gas phase and solid state (ices) environments. These are a crossed molecular beams machine (3) and a surface scattering setup (4). We also present typical results of each setup (formation of amino acids, aldehydes, epoxides; synthesis of hydrogen terminated carbon chains as precursors to complex PAHs and to carbonaceous dust grains in general; nitriles as precursor to amino acids).

  15. Assessing the Nexus of Built, Natural, and Social Environments and Public Health Outcomes

    NASA Astrophysics Data System (ADS)

    Archer, R.; Alexander, S.; Douglas, J.

    2017-12-01

    This study investigates community-related environmental justice concerns and chemical and non-chemical health stressors from built, natural, and social environments in Southeast Los Angeles (SELA) County and East Oakland, California. The geographical distribution of health outcomes is related to the built and natural environments, as well as impacts from the social environment. A holistic systems view is important in assessing healthy behaviors within a community, because they do not occur in isolation. Geospatial analysis will be performed to integrate a total environment framework and explore the spatial patterns of exposure to chemical and non-chemical stressors and access to health-promoting environments. Geographic Information Systems (GIS) analysis using primary and secondary existing data will be performed to determine how social environments impact exposure to chemical health stressors and access to health-promoting built and natural environments. This project will develop a comprehensive list of health-promoting built and natural environments (e.g., parks and community gardens) and polluting sites (e.g., shipping ports and sources of pollution not included in federal regulatory databases) in East Oakland and SELA. California Department of Public Health and U.S. Decennial Census data will also be included for geospatial analysis to overlay the distribution of air pollution-related morbidities (e.g. asthma, diabetes, and cancer) and access to health-promoting built and natural environments and related community assets, exposure to polluting industries, social disorganization, and public health outcomes in the target areas. This research will help identify the spatial and temporal distribution and cumulative impacts of critical pollution hotspots causing community environmental health impacts. The research team will also map how social environments impact exposure to chemical health stressors and access to health-promoting built and natural environments. The process and outcomes of this research should empower communities and aid decision-makers to integrate environmental justice considerations into public health policies.

  16. Treatment of mezcal vinasses: a review.

    PubMed

    Robles-González, Vania; Galíndez-Mayer, Juvencio; Rinderknecht-Seijas, Noemí; Poggi-Varaldo, Héctor M

    2012-02-20

    Mexican distilleries produce near eight million liters of mezcal per year, and generate about 90 million liters of mezcal vinasses (MV). This acidic liquid waste is very aggressive to the environment because of its high content of toxic and recalcitrant organic matter. As a result, treatment is necessary before discharge to water bodies. It is interesting, yet disturbing; verify that there is a significant gap on the treatment of MV. However, there is an abundant body of research on treatment of other recalcitrant toxic effluents that bear some similarity to MV, for example, wine vinasse, vinasses from the sugar industry, olive oil, and industrial pulp and paper wastewaters. The objective of this review is to critically organize the treatment alternatives of MV, assess their relative advantages and disadvantages, and finally detect the trends for future research and development. Experience with treatment of this set of residuals, indicates the following trends: (i) anaerobic digestion, complemented by oxidative chemical treatments (e.g. ozonation) are usually placed as pretreatments, (ii) aerobic treatment alone and combined with ozone which have been directed to remove phenolic compounds and color have been successfully applied, (iii) physico-chemical treatments such as Fenton, electro-oxidation, oxidants and so on., which are now mostly at lab scale stage, have demonstrated a significant removal of recalcitrant organic compounds, (iv) fungal pretreatment with chemical treatment followed by oxidative (O(3)) or anaerobic digestion, this combination seems to give attractive results, (v) vinasses can be co-composted with solid organic wastes, particularly with those from agricultural activities and agro-industies; in addition to soil amenders with fertilizing value to improve soil quality in typical arid lands where agave is cultivated, it seems to be a low cost technology very well suited for rural regions in underdeveloped countries where more sophisticated technologies are difficult to adopt, due to high costs and requirements of skilled personnel. Copyright © 2011 Elsevier B.V. All rights reserved.

  17. Immediate impact on the rim zone of cement based materials due to chemical attack

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

    Schwotzer, M., E-mail: matthias.schwotzer@kit.edu; Scherer, T.; Gerdes, A.

    2015-01-15

    Cement based materials are in their widespread application fields exposed to various aqueous environments. This can lead to serious chemical changes affecting the durability of the materials. In particular in the context of service life prediction a detailed knowledge of the reaction mechanisms is a necessary base for the evaluation of the aggressivity of an aqueous medium and this is deduced commonly from long term investigations. However, these processes start immediately at the material/water-interface, when a cementitious system comes into contact with an aqueous solution, altering here the chemical composition and microstructure. This rim zone represents the first hurdle thatmore » has to be overcome by an attacking aqueous solution. Therefore, the properties of the surface near area should be closely associated with the further course of deterioration processes by reactive transport. In this context short term exposure experiments with hardened cement paste over 4 and 48 h have been carried out with demineralized water, hard tap water and different sulfate solutions. In order to investigate immediate changes in the near-surface region, depth profile cuts have been performed on the cement paste samples by means of focused ion beam preparation techniques. A scanning beam of Gallium ions is applied to cut a sharp edge in the cement paste surface, providing insights into the composition and microstructure of the upper ten to hundred microns. Electron microscopic investigations on such a section of the rim zone, together with surface sensitive X-ray diffraction accompanied by a detailed characterization of the bulk composition confirm that the properties of the material/water interface are of relevance for the durability of cement based systems in contact with aqueous solutions. In this manner, focused ion beam investigations constitute auspicious tools to contribute to a more sophisticated understanding of the reaction mechanisms. - Highlights: • The chemical stability is related to the properties of material/water interface. • Properties of the rim zone readjust quickly, triggered by hydrochemical conditions. • Durability research can be improved by combining FIB techniques and common analytics.« less

  18. Chemical performance of multi-environment trials in lens (Lens culinaris M.).

    PubMed

    Karadavut, Ufuk; Palta, Cetin

    2010-01-15

    Genotype-environment (GE) interaction has been a major effect to determine stable lens (Lens culinaris (Medik.) Merr.) cultivars for chemical composition in Turkey. Utilization of the lines depends on their agronomic traits and stability of the chemical composition in diverse environments. The objectives of this study were: (i) to evaluate the influence of year and location on the chemical composition of lens genotypes; and (ii) to determine which cultivar is the most stable. Genotypes were evaluated over 3 years (2005, 2006 and 2007) at four locations in Turkey. Effects of year had the largest impact on all protein contents. GE interaction was analyzed by using linear regression techniques. Stability was estimated using the Eberhart and Russell method. 'Kişlik Kirmizi51' was the most stable cultivar for grain yield. The highest protein was obtained from 'Kişlik Kirmizi51' (4.6%) across environments. According to stability analysis, 'Firat 87' had the most stable chemical composition. This genotype had a regression coefficient (b(i) = 1) around unity, and deviations from regression values (delta(ij) = 0) around zero. Chemical composition was affected by year in this study. Temperature might have an effect on protein, oil, carbohydrate, fibre and ash. Firat 87 could be recommended for favourable environments. Copyright (c) 2009 Society of Chemical Industry.

  19. Normative beliefs about aggression and cyber aggression among young adults: a longitudinal investigation.

    PubMed

    Wright, Michelle F; Li, Yan

    2013-01-01

    This longitudinal study examined normative beliefs about aggression (e.g., face-to-face, cyber) in relation to the engagement in cyber aggression 6 months later among 126 (69 women) young adults. Participants completed electronically administered measures assessing their normative beliefs, face-to-face and cyber aggression at Time 1, and cyber aggression 6 months later (Time 2). We found that men reported more cyber relational and verbal aggression when compared to women. After controlling for each other, Time 1 face-to-face relational aggression was positively related to Time 2 cyber relational aggression, whereas Time 1 face-to-face verbal aggression was positively related to Time 2 cyber verbal aggression. Normative beliefs regarding cyber aggression was positively related to both forms of cyber aggression 6 months later, after controlling for normative beliefs about face-to-face aggression. Furthermore, a significant two-way interaction between Time 1 cyber relational aggression and normative beliefs about cyber relational aggression was found. Follow-up analysis showed that Time 1 cyber relational aggression was more strongly related to Time 2 cyber relational aggression when young adults held higher normative beliefs about cyber relational aggression. A similar two-way interaction was found for cyber verbal aggression such that the association between Time 1 and Time 2 cyber verbal aggression was stronger at higher levels of normative beliefs about cyber verbal aggression. Results are discussed in terms of the social cognitive and behavioral mechanisms associated with the engagement of cyber aggression. © 2013 Wiley Periodicals, Inc.

  20. Laser-Based Remote Sensing of Explosives by a Differential Absorption and Scattering Method

    NASA Astrophysics Data System (ADS)

    Ayrapetyan, V. S.

    2018-01-01

    A multifunctional IR parametric laser system is developed and tested for remote detection and identification of atmospheric gases, including explosive and chemically aggressive substances. Calculations and experimental studies of remote determination of the spectroscopic parameters of the best known explosive substances TNT, RDX, and PETN are carried out. The feasibility of high sensitivity detection ( 1 ppm) of these substances with the aid of a multifunctional IR parametric light source by differential absorption and scattering is demonstrated.

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