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Sample records for behavioral resistance

  1. Leptin resistance and hippocampal behavioral deficits.

    PubMed

    Van Doorn, Catherine; Macht, Victoria A; Grillo, Claudia A; Reagan, Lawrence P

    2017-03-04

    The adipocyte-derived hormone leptin is an important regulator of body weight and metabolism through activation of brain leptin receptors expressed in regions such as the hypothalamus. Beyond these well described and characterized activities of leptin in the hypothalamus, it is becoming increasingly clear that the central activities of leptin extend to the hippocampus. Indeed, leptin receptors are expressed in the hippocampus where these receptors are proposed to mediate various aspects of hippocampal synaptic plasticity that ultimately impact cognitive function. This concept is supported by studies demonstrating that leptin promotes hippocampal-dependent learning and memory, as well as studies indicating that leptin resistance is associated with deficits in hippocampal-dependent behaviors and in the induction of depressive-like behaviors. The effects of leptin on cognitive/behavioral plasticity in the hippocampus may be regulated by direct activation of leptin receptors expressed in the hippocampus; additionally, leptin-mediated activation of synaptic networks that project to the hippocampus may also impact hippocampal-mediated behaviors. In view of these previous observations, the goal of this review will be to discuss the mechanisms through which leptin facilitates cognition and behavior, as well as to dissect the loci at which leptin resistance leads to impairments in hippocampal synaptic plasticity, including the development of cognitive deficits and increased risk of depressive illness in metabolic disorders such as obesity and type 2 diabetes mellitus (T2DM).

  2. Resistance to extinction and behavioral momentum.

    PubMed

    Nevin, John A

    2012-05-01

    In the metaphor of behavioral momentum, reinforcement is assumed to strengthen discriminated operant behavior in the sense of increasing its resistance to disruption, and extinction is viewed as disruption by contingency termination and reinforcer omission. In multiple schedules of intermittent reinforcement, resistance to extinction is an increasing function of reinforcer rate, consistent with a model based on the momentum metaphor. The partial-reinforcement extinction effect, which opposes the effects of reinforcer rate, can be explained by the large disruptive effect of terminating continuous reinforcement despite its strengthening effect during training. Inclusion of a term for the context of reinforcement during training allows the model to account for a wide range of multiple-schedule extinction data and makes contact with other formulations. The relation between resistance to extinction and reinforcer rate on single schedules of intermittent reinforcement is exactly opposite to that for multiple schedules over the same range of reinforcer rates; however, the momentum model can give an account of resistance to extinction in single as well as multiple schedules. An alternative analysis based on the number of reinforcers omitted to an extinction criterion supports the conclusion that response strength is an increasing function of reinforcer rate during training.

  3. Observations and simulations of resistance switching behavior

    NASA Astrophysics Data System (ADS)

    Choi, Sukwon

    This dissertation describes an exploration to understand the electric field driven resistance switching behavior, which are known to be found in many oxide materials. The behavior is characterized as having two different stable states in their current-voltage characteristics. They have gained much attention as candidates for data storage. Although this interesting phenomenon has been studied for decades, the physical mechanism of the behavior is not revealed, yet. To establish our own model, experiments with Cr doped SrZrO3 are carried out and hypothetical models were developed based on the results. Then, computational calculations were done to test the proposed switching mechanism. Experiments are done using metal(top metal)/Cr-SrZrO3/SrRuO 3(bottom metal) heterojunction stacks, which are grown using Pulsed Laser Deposition system. In the structure, thickness and Cr-doping content of SrZrO3 layer were varied while Pt and Ag are used as primary top metal contacts. And top metal layer is also varied with Pt, Ag, Cu, Cr, Mg, and SrRuO3 to see the influence of top metal contact. The heterostructures were found to exhibit non-rectifying IVCs (so-called Space-Charge-Limited Current) which are observed in many other metal-oxide-metal systems. In the experiments of varying Cr-content and thickness of SrZrO 3 layer, a steep increase of resistance with respect to thickness was observed. For high Cr-doping levels, R ∝ t3 was observed, while for low Cr-doping levels an even stronger relationship was observed. The main result of top metal contact experiment was the one that metal contact's chemical identity decides the slope of IVC (resistances), where resistances were found to be correlated with top metal's heat of oxide formation. Especially for Ag top metal contact, which has the lowest absolute value of heat of oxide formation, reversal switching polarity was observed. Such results lead us to believe that the switching behavior is originated by oxygen vacancy motion with

  4. Barriers and resistance to informatics in behavioral health.

    PubMed

    Lorenzi, N M; Riley, R T; Dewan, N A

    2001-01-01

    The levels of resistance to a new informatics system can vary widely both between and among specific groups. The relevance to today's behavioral medicine area is obvious. The aim of effective change management techniques is not to eliminate all resistance. This is typically impossible when a group of any size is involved. The aims are (1) to keep initial general resistance at reasonable levels, (2) to pre-vent that initial resistance from growing to serious levels, and (3) to identify and deal with any pockets of serious resistance that do occur despite the previous efforts. His article outlines areas of resistance to behavioral informatics and offers suggestions for overcoming the resistance.

  5. Utilizing Motivational Interviewing to Address Resistant Behaviors in Clinical Supervision

    ERIC Educational Resources Information Center

    Wahesh, Edward

    2016-01-01

    Motivational interviewing is presented as an approach to address resistant behaviors in clinical supervision. A case example is used to illustrate the process in which the relational and technical elements of motivational interviewing can be applied to supervisee resistance. Implications for supervisors and researchers are discussed.

  6. Utilizing Motivational Interviewing to Address Resistant Behaviors in Clinical Supervision

    ERIC Educational Resources Information Center

    Wahesh, Edward

    2016-01-01

    Motivational interviewing is presented as an approach to address resistant behaviors in clinical supervision. A case example is used to illustrate the process in which the relational and technical elements of motivational interviewing can be applied to supervisee resistance. Implications for supervisors and researchers are discussed.

  7. Resistance to Sexual Coercion Behaviors: A Meta-Analysis.

    ERIC Educational Resources Information Center

    Emmers, Tara M.; Allen, Mike

    Both men and women are faced with relational situations in which sexually coercive behaviors are exercised. Because various studies offer mixed findings, a study utilized meta-analysis to compare men's and women's resistance to sexual coercion. Literature for the investigation was compiled from computer searches using key words such as…

  8. Effects of Behavioral History on Resistance to Change

    ERIC Educational Resources Information Center

    Doughty, Adam H.; Cirino, Sergio; Mayfield, Kristin H.; da Silva, Stephanie P.; Okouchi, Hiroto; Lattal, Kennon A.

    2005-01-01

    Two experiments examined whether differential resistance to change would occur under identical variable-interval schedules as a function of a differential behavioral history. In Experiment 1, each of 3 pigeons first pecked at different rates under a multiple variable-ratio differential-reinforcement-of-low-rate schedule. In a subsequent condition,…

  9. Effects of Behavioral History on Resistance to Change

    ERIC Educational Resources Information Center

    Doughty, Adam H.; Cirino, Sergio; Mayfield, Kristin H.; da Silva, Stephanie P.; Okouchi, Hiroto; Lattal, Kennon A.

    2005-01-01

    Two experiments examined whether differential resistance to change would occur under identical variable-interval schedules as a function of a differential behavioral history. In Experiment 1, each of 3 pigeons first pecked at different rates under a multiple variable-ratio differential-reinforcement-of-low-rate schedule. In a subsequent condition,…

  10. Resistance behavior of Cr-Si-O thin films

    SciTech Connect

    Jankowski, A.F.; Hayes, J.P.; Musket, R.; Cosandey, F.; Gorla, C.E.; Besser, R.S.; Westerlind, V.; Cobai, G.

    1996-10-23

    Thin coatings of Cr-Si-O are assessed for use as a resistor. The submicron thick films are sputter deposited using a (l-x)Ar-(x)O{sub 2} working gas. Several compacts of metal and oxide powders are commercially prepared for use as the sputter targets. The deposition process yields film compositions which range from 2 to 30 at.% Cr and 20 to 45 at.% Si as measured using Rutherford backscattering. A broad range of resistivities from 10{sup 1} to 10{sup 14}{Omega} cm are found as measured through the film thickness between metal pads deposited onto the Cr-Si-O surface. The film structure and morphology are characterized using transmission electron microscopy from which the resistance behavior can be correlated to the distribution of metallic particles. Thermal aging reveals the metastability of the Cr- Si-O film morphology and resistance behavior.

  11. Observation of Anomalous Resistance Behavior in Bilayer Graphene

    NASA Astrophysics Data System (ADS)

    Liu, Yanping; Lew, Wen Siang; Liu, Zongwen

    2017-01-01

    Our measurement results have shown that bilayer graphene exhibits an unexpected sharp transition of the resistance value in the temperature region 200 250 K. We argue that this behavior originates from the interlayer ripple scattering effect between the top and bottom ripple graphene layer. The inter-scattering can mimic the Coulomb scattering but is strongly dependent on temperature. The observed behavior is consistent with the theoretical prediction that charged impurities are the dominant scatters in bilayer graphene. The resistance increase with increasing perpendicular magnetic field strongly supports the postulate that magnetic field induces an excitonic gap in bilayer graphene. Our results reveal that the relative change of resistance induced by magnetic field in the bilayer graphene shows an anomalous thermally activated property.

  12. Negative differential resistance and resistance switching behaviors in BaTiO{sub 3} thin films

    SciTech Connect

    Yang, G.; Jia, C. H. E-mail: wfzhang@henu.edu.cn Chen, X.; Zhang, W. F. E-mail: wfzhang@henu.edu.cn; Chen, Y. H.

    2014-05-28

    The polycrystalline BaTiO{sub 3} (BTO) thin films were grown on F-doped SnO{sub 2} substrates by pulsed laser deposition. The devices show a rectification at a small voltage, while bipolar resistive switching (RS) and negative differential resistance (NDR) appear at a large voltage. Furthermore, RS remains and NDR disappears when no positive bias is applied, while both RS and NDR behaviors improve when increasing the positive bias. The electrons trapped/detrapped by interface states at Au/BTO interface are proposed to understand the above behaviors.

  13. Magnetoresistance Behavior of Conducting Filaments in Resistive-Switching NiO with Different Resistance States.

    PubMed

    Zhao, Diyang; Qiao, Shuang; Luo, Yuxiang; Chen, Aitian; Zhang, Pengfei; Zheng, Ping; Sun, Zhong; Guo, Minghua; Chiang, Fu-Kuo; Wu, Jian; Luo, Jianlin; Li, Jianqi; Kokado, Satoshi; Wang, Yayu; Zhao, Yonggang

    2017-03-29

    The resistive switching (RS) effect in various materials has attracted much attention due to its interesting physics and potential for applications. NiO is an important system and its RS effect has been generally explained by the formation/rupture of Ni-related conducting filaments. These filaments are unique since they are formed by an electroforming process, so it is interesting to explore their magnetoresistance (MR) behavior, which can also shed light on unsolved issues such as the nature of the filaments and their evolution in the RS process, and this behavior is also important for multifunctional devices. Here, we focus on MR behavior in NiO RS films with different resistance states. Rich and interesting MR behaviors have been observed, including the normal and anomalous anisotropic magnetoresistance and tunneling magnetoresistance, which provide new insights into the nature of the filaments and their evolution in the RS process. First-principles calculation reveals the essential role of oxygen migration into the filaments during the RESET process and can account for the experimental results. Our work provides a new avenue for exploration of the conducting filaments in resistive switching materials and is significant for understanding the mechanism of RS effect and multifunctional devices.

  14. Brief behavioral treatment for patients with treatment-resistant insomnia

    PubMed Central

    Wang, Jihui; Wei, Qinling; Wu, Xiaoli; Zhong, Zhiyong; Li, Guanying

    2016-01-01

    Objective To evaluate the efficacy of brief behavioral treatment for insomnia (BBTI) in treating patients with treatment-resistant insomnia. Methods Seventy-nine adults with treatment-resistant insomnia were randomly assigned to receive either individualized BBTI (delivered in two in-person sessions and two telephone “booster” sessions, n=40) or sleep hygiene education (n=39). The primary outcome was subjective (sleep diary) measures of self-report symptoms and questionnaire measures of Pittsburgh sleep quality index (PSQI), insomnia severity index (ISI), Epworth sleeping scale (ESS), and dysfunctional beliefs and attitudes about sleep scale (DBAS). Results The repeated-measures analysis of variance showed significant time effects between pretreatment and posttreatment in the scale ratings of PSQI, ESS, DBAS, ISI, sleep latency (SL), time in bed (TIB), sleep efficiency (SE), and wake after sleep onset (WASO) in both groups and group × time interaction (FPSQI =3.893, FESS =4.500, FDBAS =5.530, FISI =15.070, FSL =8.909, FTIB =7.895, FSE =2.926, and FWASO =2.595). The results indicated significant differences between BBTI and sleep hygiene in change scores of PSQI, ESS, DBAS, ISI, SL, TIB, SE, and WASO. Effect sizes were moderate to large. Conclusion BBTI is a simple and efficacious intervention for chronic insomnia in adults. PMID:27536119

  15. Eastern mosquitofish resists invasion by nonindigenous poeciliids through agonistic behaviors

    USGS Publications Warehouse

    Thompson, Kevin A.; Hill, Jeffrey E.; Nico, Leo G.

    2012-01-01

    Florida is a hotspot for nonindigenous fishes with over 30 species established, although few of these are small-bodied species. One hypothesis for this pattern is that biotic resistance of native species is reducing the success of small-bodied, introduced fishes. The eastern mosquitofish Gambusia holbrooki is common in many freshwater habitats in Florida and although small-bodied (<50 mm), it is a predator and aggressive competitor. We conducted four mesocosm experiments to examine the potential for biotic resistance by eastern mosquitofish to two small-bodied nonindigenous fishes, variable platyfish (Xiphophorus variatus) and swordtail (X. hellerii). Experiments tested: (1) effect of eastern mosquitofish density on adult survival, (2) effect of eastern mosquitofish on a stage-structured population, (3) role of habitat structural complexity on nonindigenous adult survival, and (4) behavioral effects of eastern mosquitofish presence and habitat complexity. Eastern mosquitofish attacked and killed non-native poeciliids with especially strong effects on juveniles of both species. Higher eastern mosquitofish density resulted in greater effects. Predation on swordtails increased with increasing habitat complexity. Eastern mosquitofish also actively drove swordtails from cover, which could expose non-native fish to other predators under field conditions. Our results suggest that eastern mosquitofish may limit invasion success.

  16. Macro model for stochastic behavior of resistance distribution of magnetic tunnel junction

    NASA Astrophysics Data System (ADS)

    Kil, Gyuhyun; Choi, Juntae; Song, Yunheub

    2015-04-01

    In this work, we fabricated MgO-based magnetic tunnel junction (MTJ) samples to observe behavior of resistance variation, and investigated a stochastic behavior model for MTJ resistance from measured real data. We found the relationship between parallel resistance (RP), anti-parallel resistance (RAP), and TMR from the measurements. The variation of barrier thickness affects not only resistance but also TMR. This means that broad RAP distribution is caused by RP distribution. In addition, RAP distribution can be reduced by increasing temperature and bias voltage. We developed a macro model that can evaluate resistance distribution based on the stochastic behavior of MTJ resistance variation from only tox varied. The amount of resistance variation, which is considered with regard to the circuit performance, can be obtained from Δtox designed by designer. In addition, the impact for operating circumstance such as bias and temperature can be considered by using fit equations.

  17. Relations between Children's Levels of Responsiveness and Resistance, Maternal Interaction Behaviors, and Children's Social Behaviors with Peers in School

    ERIC Educational Resources Information Center

    Salinas, Daniela; Neitzel, Carin

    2017-01-01

    Children's peer relationships have their origins in family relationships. The present study focuses on the relative importance of children's levels of responsiveness and/or resistance during mother-child interactions and tests a model of the direct and indirect relations between mother interaction behaviors and children's social behaviors with…

  18. Relations between Children's Levels of Responsiveness and Resistance, Maternal Interaction Behaviors, and Children's Social Behaviors with Peers in School

    ERIC Educational Resources Information Center

    Salinas, Daniela; Neitzel, Carin

    2017-01-01

    Children's peer relationships have their origins in family relationships. The present study focuses on the relative importance of children's levels of responsiveness and/or resistance during mother-child interactions and tests a model of the direct and indirect relations between mother interaction behaviors and children's social behaviors with…

  19. Electrical resistivity behaviors of liquid Pb-Sn binary alloy in the presence of ultrasonic field.

    PubMed

    Liu, Xuan; Zhang, Jianfeng; Li, Haoyu; Le, Qichi; Zhang, Zhiqiang; Hu, Wenyi; Bao, Lei

    2015-01-01

    Electrical resistivity behaviors of liquid Pb-Sn alloys have been investigated in the presence of ultrasonic field. The process demonstrated significantly that electrical resistivity could reveal the precise influence caused by ultrasound. Details revealed by applying the resistivity measuring approach to the liquid Pb-Sn alloy show that the short ordered structures in the liquid could be modified by ultrasonic irradiation, and the resistivity approach could have application value in the ultrasonic irradiation process on the specific liquid metals and alloys.

  20. Association between risk behaviors and antiretroviral resistance in HIV-infected patients receiving opioid agonist treatment.

    PubMed

    Tetrault, Jeanette M; Kozal, Michael J; Chiarella, Jennifer; Sullivan, Lynn E; Dinh, An T; Fiellin, David A

    2013-01-01

    Antiretroviral (ARV) resistance is of concern. Opioid agonist treatment (ie, methadone or buprenorphine) is effective and decreases HIV transmission risk behaviors and HIV seroconversion. Despite prevention efforts, injection drug use (IDU) and risky sexual behaviors remain prevalent in patients receiving opioid agonist treatment. The purpose of this study is to determine in HIV-infected patients receiving opioid agonist treatment, the prevalence of HIV transmission risk behaviors, the prevalence of ARV resistance, and the prevalence of ARV resistance among those with risk behaviors. The design was a cross-sectional study of patients recruited from opioid treatment programs and outpatient practices. We measured demographic, drug treatment, and HIV clinical information (including ARV adherence), self-reported HIV risk behaviors and drug use, urine toxicologies, and genotype testing for ARV resistance (with both standard assays and ultradeep sequencing). Data analysis included descriptive statistics. Fifty-nine subjects were enrolled, 64% were male, 24% were white, and mean age was 46 years. Fifty-three percent were receiving methadone, 47% were receiving buprenorphine, and 80% were receiving opioid agonist treatment for 12 weeks or more. Fourteen percent reported unprotected sex, 7% reported sharing needles or works, and 60% had positive urine toxicology for illicit drug use. Fifteen percent had evidence of HIV resistance by standard genotyping; 7% with single class resistance, 3% with double class resistance, and 5% with triple class resistance. Ultradeep sequencing found additional class resistance in 5 subjects. Twenty-two percent of subjects with evidence of transmission risk behaviors versus 14% of subjects without risk behaviors had evidence of ARV resistance. Improved prevention and treatment efforts may be needed for HIV-infected, opioid dependent individuals receiving opioid agonist treatment to decrease transmission of ARV resistant virus, especially in

  1. Socioeconomic and behavioral factors leading to acquired bacterial resistance to antibiotics in developing countries.

    PubMed Central

    Okeke, I. N.; Lamikanra, A.; Edelman, R.

    1999-01-01

    In developing countries, acquired bacterial resistance to antimicrobial agents is common in isolates from healthy persons and from persons with community-acquired infections. Complex socioeconomic and behavioral factors associated with antibiotic resistance, particularly regarding diarrheal and respiratory pathogens, in developing tropical countries, include misuse of antibiotics by health professionals, unskilled practitioners, and laypersons; poor drug quality; unhygienic conditions accounting for spread of resistant bacteria; and inadequate surveillance. PMID:10081668

  2. Behavioral Avoidance - Will Physiological Insecticide Resistance Level of Insect Strains Affect Their Oviposition and Movement Responses?

    PubMed Central

    Nansen, Christian; Baissac, Olivier; Nansen, Maria; Powis, Kevin; Baker, Greg

    2016-01-01

    Agricultural organisms, such as insect herbivores, provide unique opportunities for studies of adaptive evolutionary processes, including effects of insecticides on movement and oviposition behavior. In this study, Brassica leaves were treated with one of two non-systemic insecticides and exposed to two individual strains (referred to as single or double resistance) of diamondback moth (Plutella xylostella) (DBM) exhibiting physiological resistance. Behavioral responses by these two strains were compared as part of characterizing the relative effect of levels of physiological resistance on the likelihood of insects showing signs of behavioral avoidance. For each DBM strain, we used choice bioassays to quantify two possible types of behavioral avoidance: 1) females ovipositing predominantly on leaf surfaces without insecticides, and 2) larvae avoiding insecticide-treated leaf surfaces. In three-choice bioassays (leaves with no pesticide, 50% coverage with pesticide, or 100% coverage with pesticide), females from the single resistance DBM strain laid significantly more eggs on water treated leaves compared to leaves with 100% insecticide coverage (both gamma-cyhalothrin and spinetoram). Females from the double resistance DBM strain also laid significantly more eggs on water treated leaves compared to leaves with 100% gamma-cyhalothrin, while moths did not adjust their oviposition behavior in response to spinetoram. Larvae from the single resistance DBM strain showed a significant increase in mobility in response to both insecticides and avoided insecticide-treated portions of leaves when given a choice. On the other hand, DBM larvae from the double resistance strain showed a significant decrease in mobility in response to insecticides, and they did not avoid insecticide-treated portions of leaves when given a choice. Our results suggest that pest populations with physiological resistance may show behavioral avoidance, as resistant females avoided oviposition on

  3. Behavioral Avoidance - Will Physiological Insecticide Resistance Level of Insect Strains Affect Their Oviposition and Movement Responses?

    PubMed

    Nansen, Christian; Baissac, Olivier; Nansen, Maria; Powis, Kevin; Baker, Greg

    2016-01-01

    Agricultural organisms, such as insect herbivores, provide unique opportunities for studies of adaptive evolutionary processes, including effects of insecticides on movement and oviposition behavior. In this study, Brassica leaves were treated with one of two non-systemic insecticides and exposed to two individual strains (referred to as single or double resistance) of diamondback moth (Plutella xylostella) (DBM) exhibiting physiological resistance. Behavioral responses by these two strains were compared as part of characterizing the relative effect of levels of physiological resistance on the likelihood of insects showing signs of behavioral avoidance. For each DBM strain, we used choice bioassays to quantify two possible types of behavioral avoidance: 1) females ovipositing predominantly on leaf surfaces without insecticides, and 2) larvae avoiding insecticide-treated leaf surfaces. In three-choice bioassays (leaves with no pesticide, 50% coverage with pesticide, or 100% coverage with pesticide), females from the single resistance DBM strain laid significantly more eggs on water treated leaves compared to leaves with 100% insecticide coverage (both gamma-cyhalothrin and spinetoram). Females from the double resistance DBM strain also laid significantly more eggs on water treated leaves compared to leaves with 100% gamma-cyhalothrin, while moths did not adjust their oviposition behavior in response to spinetoram. Larvae from the single resistance DBM strain showed a significant increase in mobility in response to both insecticides and avoided insecticide-treated portions of leaves when given a choice. On the other hand, DBM larvae from the double resistance strain showed a significant decrease in mobility in response to insecticides, and they did not avoid insecticide-treated portions of leaves when given a choice. Our results suggest that pest populations with physiological resistance may show behavioral avoidance, as resistant females avoided oviposition on

  4. Isolated cell behavior drives the evolution of antibiotic resistance.

    PubMed

    Artemova, Tatiana; Gerardin, Ylaine; Dudley, Carmel; Vega, Nicole M; Gore, Jeff

    2015-07-29

    Bacterial antibiotic resistance is typically quantified by the minimum inhibitory concentration (MIC), which is defined as the minimal concentration of antibiotic that inhibits bacterial growth starting from a standard cell density. However, when antibiotic resistance is mediated by degradation, the collective inactivation of antibiotic by the bacterial population can cause the measured MIC to depend strongly on the initial cell density. In cases where this inoculum effect is strong, the relationship between MIC and bacterial fitness in the antibiotic is not well defined. Here, we demonstrate that the resistance of a single, isolated cell-which we call the single-cell MIC (scMIC)-provides a superior metric for quantifying antibiotic resistance. Unlike the MIC, we find that the scMIC predicts the direction of selection and also specifies the antibiotic concentration at which selection begins to favor new mutants. Understanding the cooperative nature of bacterial growth in antibiotics is therefore essential in predicting the evolution of antibiotic resistance. © 2015 The Authors. Published under the terms of the CC BY 4.0 license.

  5. Isolated cell behavior drives the evolution of antibiotic resistance

    PubMed Central

    Artemova, Tatiana; Gerardin, Ylaine; Dudley, Carmel; Vega, Nicole M; Gore, Jeff

    2015-01-01

    Bacterial antibiotic resistance is typically quantified by the minimum inhibitory concentration (MIC), which is defined as the minimal concentration of antibiotic that inhibits bacterial growth starting from a standard cell density. However, when antibiotic resistance is mediated by degradation, the collective inactivation of antibiotic by the bacterial population can cause the measured MIC to depend strongly on the initial cell density. In cases where this inoculum effect is strong, the relationship between MIC and bacterial fitness in the antibiotic is not well defined. Here, we demonstrate that the resistance of a single, isolated cell—which we call the single-cell MIC (scMIC)—provides a superior metric for quantifying antibiotic resistance. Unlike the MIC, we find that the scMIC predicts the direction of selection and also specifies the antibiotic concentration at which selection begins to favor new mutants. Understanding the cooperative nature of bacterial growth in antibiotics is therefore essential in predicting the evolution of antibiotic resistance. PMID:26227664

  6. Oppositional Behavior in Urban Schooling: Toward a Theory of Resistance for New Times

    ERIC Educational Resources Information Center

    Nolan, Kathleen M.

    2011-01-01

    Early resistance theorists analyzed working class students' oppositional behavior at a time of high availability of viable jobs in manufacturing. They argued that oppositional behavior constituted a rejection of middle class culture motivated by an implicit understanding of the myth of meritocracy. But times have changed. This paper seeks to…

  7. Oppositional Behavior in Urban Schooling: Toward a Theory of Resistance for New Times

    ERIC Educational Resources Information Center

    Nolan, Kathleen M.

    2011-01-01

    Early resistance theorists analyzed working class students' oppositional behavior at a time of high availability of viable jobs in manufacturing. They argued that oppositional behavior constituted a rejection of middle class culture motivated by an implicit understanding of the myth of meritocracy. But times have changed. This paper seeks to…

  8. Analysis of the resistive switching behaviors of vanadium oxide thin film

    NASA Astrophysics Data System (ADS)

    Wei, Xiao-Ying; Hu, Ming; Zhang, Kai-Liang; Wang, Fang; Zhao, Jin-Shi; Miao, Yin-Ping

    2013-03-01

    We demonstrate the polarization of resistive switching for a Cu/VOx/Cu memory cell. The switching behaviors of Cu/VOx/Cu cell are tested by using a semiconductor device analyzer (Agilent B1500A), and the relative micro-analysis of I—V characteristics of VOx/Cu is characterized by using a conductive atomic force microscope (CAFM). The I—V test results indicate that both the forming and the reversible resistive switching between low resistance state (LRS) and high resistance state (HRS) can be observed under either positive or negative sweep. The CAFM images for LRS and HRS directly exhibit evidence for the formation and rupture of filaments based on positive or negative voltage. The Cu/VOx/Cu sandwiched structure exhibits reversible resistive switching behavior and shows potential applications in the next generation of nonvolatile memory.

  9. Evolutionary origins of insulin resistance: a behavioral switch hypothesis

    PubMed Central

    Watve, Milind G; Yajnik, Chittaranjan S

    2007-01-01

    Background Insulin resistance, which can lead to a number of diseases including type 2 diabetes and coronary heart disease, is believed to have evolved as an adaptation to periodic starvation. The "thrifty gene" and "thrifty phenotype" hypotheses constitute the dominant paradigm for over four decades. With an increasing understanding of the diverse effects of impairment of the insulin signaling pathway, the existing hypotheses are proving inadequate. Presentation of the hypothesis We propose a hypothesis that insulin resistance is a socio-ecological adaptation that mediates two phenotypic transitions, (i) a transition in reproductive strategy from "r" (large number of offspring with little investment in each) to "K" (smaller number of offspring with more investment in each) and (ii) a transition from "stronger to smarter" or "soldier to diplomat" i.e. from relatively more muscle dependent to brain dependent lifestyle. A common switch could have evolved for the two transitions since the appropriate environmental conditions for the two transitions are highly overlapping and interacting. Testing the hypothesis Gestational insulin resistance diverts more energy through the placenta, resulting in increased investment per offspring. On the other hand, insulin resistance is associated with reduced ovulation. The insulin signaling pathway is also related to longevity. Insulin resistance diverts more nutrients to the brain as compared to muscle. Also, hyperinsulinemia has direct positive effects on cognitive functions of the brain. The hypothesis gets support from known patterns in human clinical data and recent research on the molecular interactions in the insulin signaling pathway. Further we state many predictions of the hypothesis that can be tested experimentally or epidemiologically. Implications of the hypothesis The hypothesis can bring about a significant change in the line of treatment as well as public health policies for the control of metabolic syndrome. PMID

  10. Top electrode effects on resistive switching behavior in CuO thin films

    NASA Astrophysics Data System (ADS)

    Li, Ying; Zhao, Gaoyang; Su, Jian; Shen, Erfeng; Ren, Yang

    2011-09-01

    Top electrode (TE) material on the resistive switching behavior of (TE)/CuO/SnO2:F/Si substrate has been studied. We investigated the switching properties of CuO films deposited by sol-gel process. Two kinds of top electrode (TE) material on the resistive switching behaviors have been studied. The nonpolar and bipolar resistive switching phenomenon was observed in CuO thin films with different top electrodes. The filamentary mechanism was used to explain the two kinds of resistive switching behaviors. For the Pt/CuO/ATO device, it showed the nonpolar resistive switching where conducting path is formed and disappear due to the oxygen vacancy. For the Cu/CuO/ATO device, the resistance reduction is due to the existing Cu to form conduction Cu-rich pathways. An opposite bias takes the existing Cu back to the Cu electrode to its high-resistance state. CuO thin films are also observed by XRD, AFM and XPS.

  11. Brief Report: An Experimental Analogue of Consultee "Resistance" Effects on the Consultant's Therapeutic Behavior--A Preliminary Investigation

    ERIC Educational Resources Information Center

    Cautilli, Joseph; Riley-Tillman, T. Chris

    2006-01-01

    This study presents an experimental analogue of resistance in the consultation process. Using an ABAB reversal design, the experimenter measured the ecological effects of teacher resistant behaviors on consultant therapeutic behavior. The study defined therapeutic behaviors as teaching, confronting and problem identification, analysis, and…

  12. Agitation and resistiveness to care are two separate behavioral syndromes of dementia.

    PubMed

    Volicer, Ladislav; Bass, Elizabeth A; Luther, Stephen L

    2007-10-01

    To distinguish two behavioral syndromes of dementia: Agitation and resistiveness to care. Analysis of Minimum Data Set (MDS) data. MDS data from Veterans Administration nursing homes collected from October 13, 2000, through October 14, 2004. Participants were 23,837 residents with a positive diagnosis for Alzheimer's disease or dementia other than Alzheimer's. Presence of agitation in each patient was based on the recorded value for 6 MDS variables: repetitive questions, repetitive verbalizations, expressions of what appear to be unrealistic fears, repetitive health complaints, repetitive anxious complaints or concerns, and repetitive physical movements. Patients who exhibited the MDS variable "resists care; resisted taking medications/injections, ADL assistance or eating" anytime within the last 7 days of the assessment and whose behavior was not easily altered were considered "resistive to care." Severity of dementia was measured by the Cognitive Performance Scale using 3 MDS items: short-term memory, cognitive skills for daily decision making, and making self understood. Agitation alone was present in 17%, resistiveness to care alone in 9%, and both syndromes in 8% of residents. Agitation was present in a significant number of residents who were borderline intact, was most common in subjects with moderate cognitive impairment, and decreased thereafter. In contrast, resistiveness to care was relatively rare in borderline intact and mildly impaired residents and increased gradually, with the highest prevalence in those with very severe cognitive impairment. The prevalence of resistiveness to care increased as the ability to understand deteriorated. Most residents who were rated as having abusive symptoms were also resistive to care. Agitation and resistiveness to care are 2 separate behavioral syndromes that may also occur together. It is important to distinguish between agitation and resistiveness to care because these syndromes require different management

  13. Probing behavior of Empoasca vitis (Homoptera: Cicadellidae) on resistant and susceptible cultivars of tea plants.

    PubMed

    Miao, Jin; Han, Bao-Yu; Zhang, Qing-He

    2014-01-01

    Feeding activities of the tea green leafhopper, Empoasca vitis (Gothe) (Homoptera: Cicadellidae), on resistant and susceptible cultivars of tea plants (Camellia sinensis L.) were recorded and analyzed using the direct current electrical penetration graph (EPG) system. Six distinct EPG waveforms characterizing the feeding behavior of the tea green leafhopper, categorized as waveforms A, C, E, S, F, and R, were obtained during the investigation. Duration of passive ingestion, possibly of phloem (E), was the longest among all the probing waveforms on susceptible cultivars, whereas durations of the salivation (S) waveform and stylet work waveform (F) became longer on resistant cultivars. The durations of waveforms S and F on the resistant cultivar Jiandecha were slightly longer than those on the less resistant cultivar Yunguidaye, and both were significantly longer than those on the susceptible cultivars Hangzhoudaye and Zhushan-1. Waveform E was shorter on the resistant cultivar Jiandecha than on the less resistant cultivars Yunguidaye and was significantly shorter than on the susceptible cultivars (Hangzhoudaye and Zhushan-1). It is suggested that E, S, and F are the important waveforms related to leafhopper feeding behavior and tea plant resistance. Based on the results, the resistance levels of tea cultivars against the tea leafhopper can be evaluated quickly by direct current EPG. © The Author 2014. Published by Oxford University Press on behalf of the Entomological Society of America.

  14. Controlling the Resistive Switching Behavior in Starch-Based Flexible Biomemristors.

    PubMed

    Raeis-Hosseini, Niloufar; Lee, Jang-Sik

    2016-03-23

    Implementation of biocompatible materials in resistive switching memory (ReRAM) devices provides opportunities to use them in biomedical applications. We demonstrate a robust, nonvolatile, flexible, and transparent ReRAM based on potato starch. We also introduce a biomolecular memory device that has a starch-chitosan composite layer. The ReRAM behavior can be controlled by mixing starch with chitosan in the resistive switching layer. Whereas starch-based biomemory devices which show abrupt changes in current level; the memory device with mixed biopolymers undergoes gradual changes. Both devices exhibit uniform and robust programmable memory properties for nonvolatile memory applications. The explicated source of the bipolar resistive switching behavior is assigned to formation and rupture of carbon-rich filaments. The gradual set/reset behavior in the memory device based on a starch-chitosan mixture makes it suitable for use in neuromorphic devices.

  15. Resistance to exercise-induced weight loss: compensatory behavioral adaptations.

    PubMed

    Melanson, Edward L; Keadle, Sarah Kozey; Donnelly, Joseph E; Braun, Barry; King, Neil A

    2013-08-01

    In many interventions that are based on an exercise program intended to induce weight loss, the mean weight loss observed is modest and sometimes far less than what the individual expected. The individual responses are also widely variable, with some individuals losing a substantial amount of weight, others maintaining weight, and a few actually gaining weight. The media have focused on the subpopulation that loses little weight, contributing to a public perception that exercise has limited utility to cause weight loss. The purpose of the symposium was to present recent, novel data that help explain how compensatory behaviors contribute to a wide discrepancy in exercise-induced weight loss. The presentations provide evidence that some individuals adopt compensatory behaviors, that is, increased energy intake and/or reduced activity, that offset the exercise energy expenditure and limit weight loss. The challenge for both scientists and clinicians is to develop effective tools to identify which individuals are susceptible to such behaviors and to develop strategies to minimize their effect.

  16. Resistance to exercise-induced weight loss: compensatory behavioral adaptations

    PubMed Central

    Melanson, Edward L.; Keadle, Sarah Kozey; Donnelly, Joseph E.; Braun, Barry; King, Neil A.

    2013-01-01

    In many interventions that are based on an exercise program intended to induce weight loss, the mean weight loss observed is modest and sometimes far less than the individual expected. The individual responses are also widely variable, with some individuals losing a substantial amount of weight, others maintaining weight, and a few actually gaining weight. The media have focused on the sub-population that loses little weight, contributing to a public perception that exercise has limited utility to cause weight loss. The purpose of the symposium was to present recent, novel data that help explain how compensatory behaviors contribute to a wide discrepancy in exercise-induced weight loss. The presentations provide evidence that some individuals adopt compensatory behaviors, i.e. increased energy intake and/or reduced activity, that offset the exercise energy expenditure and limit weight loss. The challenge for both scientists and clinicians is to develop effective tools to identify which individuals are susceptible to such behaviors, and to develop strategies to minimize their impact. PMID:23470300

  17. Solanum Tuber-bearing Species Resistance Behavior Against Nacobbus aberrans

    PubMed Central

    Chaves, Eliseo J.; Clausen, Andrea. M.; Franco, Javier

    2009-01-01

    Naccobus aberrans is a major pest of the potato crop in the Andean regions of Argentina, Bolivia, and Perú. It is endemic in northwest Argentina and is also found in lowlands. The resistance of eleven Andean potato landraces and three accessions of the wild tuber-bearing species Solanum acaule, S. infundibuliforme, and S. megistacrolobum were evaluated against a population of N. aberrans from Coctaca, Jujuy province, while Solanum tuberosum ssp. tuberosum ‘Spunta’, ‘Kennebec’, and ‘Frital INTA’ were evaluated against a population from the southeast of Buenos Aires province. The presence, the number of galls, and the number of individuals were recorded. In addition, a reproduction factor was calculated and races were determined. Results showed that the N. aberrans population from Coctaca corresponded to race 2 and the population from the lowlands belonged to the sugar beet group. Landrace Azul, one genotype of S. megistacrolobum, and two genotypes of S. acaule showed resistance towards the race from Coctaca while no infection was recorded in potato cultivars with the Naccobus race from the lowland area. PMID:22661771

  18. Novel Resistive Switching Behavior in Phase Separated Manganites

    NASA Astrophysics Data System (ADS)

    Guo, Hangwen; Ward, T. Zac; Sun, Dali; Snijders, Paul C.; Gai, Zheng; Shen, Jian

    2011-03-01

    Electronic phase separation plays a key role in many novel phenomena in complex materials. Manganites are a prime example of this class of materials and have recently come under increase scrutiny for possible application in resistive random-access memory (RRAM) technology. Here, we will discuss our recent work on spatially confined La5/8-xPrxCa3/8MnO3. We have discovered that it is possible to drive single electronic domain formation/annihilation through electric field pulsing. By measuring the I-V curve, we find such resistive switching is different from normal RRAM mechanisms in manganites and is closely related to the nature of electronic phase separation. These findings open these systems to a new understanding of the nature of electronic phase separation and begin the development of manganites for future applications in RRAM devices. Research sponsored by the Division of Materials Sciences and Engineering, Office of Basic Energy Sciences, U.S. Department of Energy.

  19. Review of insecticide resistance and behavioral avoidance of vectors of human diseases in Thailand

    PubMed Central

    2013-01-01

    Physiological resistance and behavioral responses of mosquito vectors to insecticides are critical aspects of the chemical-based disease control equation. The complex interaction between lethal, sub-lethal and excitation/repellent ('excito-repellent’) properties of chemicals is typically overlooked in vector management and control programs. The development of “physiological” resistance, metabolic and/or target site modifications, to insecticides has been well documented in many insect groups and disease vectors around the world. In Thailand, resistance in many mosquito populations has developed to all three classes of insecticidal active ingredients currently used for vector control with a majority being synthetic-derived pyrethroids. Evidence of low-grade insecticide resistance requires immediate countermeasures to mitigate further intensification and spread of the genetic mechanisms responsible for resistance. This can take the form of rotation of a different class of chemical, addition of a synergist, mixtures of chemicals or concurrent mosaic application of different classes of chemicals. From the gathered evidence, the distribution and degree of physiological resistance has been restricted in specific areas of Thailand in spite of long-term use of chemicals to control insect pests and disease vectors throughout the country. Most surprisingly, there have been no reported cases of pyrethroid resistance in anopheline populations in the country from 2000 to 2011. The precise reasons for this are unclear but we assume that behavioral avoidance to insecticides may play a significant role in reducing the selection pressure and thus occurrence and spread of insecticide resistance. The review herein provides information regarding the status of physiological resistance and behavioral avoidance of the primary mosquito vectors of human diseases to insecticides in Thailand from 2000 to 2011. PMID:24294938

  20. Effect of length and negative differential resistance behavior in conjugated molecular wire tetrathiafulvalene devices

    NASA Astrophysics Data System (ADS)

    Zhang, Xiaojiao; Chen, Keqiu; Long, Mengqiu; He, Jun; Gao, Yongli

    2015-07-01

    The electronic transport properties of molecular devices constructed by conjugated molecular wire tetrathiafulvalene (TTF) have been studied by applying nonequilibrium Green’s functions in combination with the density-functional theory. Two molecular junctions with different wire lengths have been considered. The results show that the current-voltage curves of TTF devices can be modulated by the length of the molecular wire and negative differential resistance behaviors are observed in these systems. The mechanisms have been proposed for the length effect and negative differential resistance behavior.

  1. Differential Reinforcement of Alternative Behavior Increases Resistance to Extinction: Clinical Demonstration, Animal Modeling, and Clinical Test of One Solution

    ERIC Educational Resources Information Center

    Mace, F. Charles; McComas, Jennifer J.; Mauro, Benjamin C.; Progar, Patrick R.; Taylor, Bridget; Ervin, Ruth; Zangrillo, Amanda N.

    2010-01-01

    Basic research with pigeons on behavioral momentum suggests that differential reinforcement of alternative behavior (DRA) can increase the resistance of target behavior to change. This finding suggests that clinical applications of DRA may inadvertently increase the persistence of target behavior even as it decreases its frequency. We conducted…

  2. Effects of sol aging on resistive switching behaviors of HfOx resistive memories

    NASA Astrophysics Data System (ADS)

    Hsu, Chih-Chieh; Sun, Jhen-Kai; Tsao, Che-Chang; Chen, Yu-Ting

    2017-03-01

    This work investigates effects of long-term sol-aging time on sol-gel HfOx resistive random access memories (RRAMs). A nontoxic solvent of ethanol is used to replace toxic 2-methoxyethanol, which is usually used in sol-gel processes. The top electrodes are fabricated by pressing indium balls onto the HfOx surface rather than by using conventional sputtering or evaporation processes. The maximum process temperature is limited to be 100 ℃. Therefore, influences of plasma and high temperature on HfOx film can be avoided. Under this circumstance, effects of sol aging time on the HfOx films can be more clearly studied. The current conduction mechanisms in low and high electric regions of the HfOx RRAM are found to be dominated by Ohmic conduction and trap-filled space charge limited conduction (TF-SCLC), respectively. When the sol aging time increases, the resistive switching characteristic of the HfOx layer becomes unstable and the transition voltage from Ohmic conduction to TF-SCLC is also increased. This suggests that an exceedingly long aging time will give a HfOx film with more defect states. The XPS results are consistent with FTIR analysis and they can further explain the unstable HfOx resistive switching characteristic induced by sol aging.

  3. Modulation of nonlinear resistive switching behavior of a TaOx-based resistive device through interface engineering

    NASA Astrophysics Data System (ADS)

    Wang, Zongwei; Kang, Jian; Yu, Zhizhen; Fang, Yichen; Ling, Yaotian; Cai, Yimao; Huang, Ru; Wang, Yangyuan

    2017-02-01

    A resistive switching device with inherent nonlinear characteristics through a delicately engineered interfacial layer is an ideal component to be integrated into passive crossbar arrays for the suppression of sneaking current, especially in ultra-dense 3D integration. In this paper, we demonstrated a TaOx-based bipolar resistive switching device with a nearly symmetrical bi-directional nonlinear feature through interface engineering. This was accomplished by introducing an ultra-thin interfacial layer (SiO2-x) with unique features, including a large band gap and a certain level of negative heat of oxide formation between the top electrode (TiN) and resistive layer (TaOx). The devices exhibit excellent nonlinear property under both positive and negative bias. Modulation of the inherent nonlinearity as well as the resistive switching mechanism are comprehensively studied by scrutinizing the results of the experimental control groups and the extensive characterizations including detailed compositional analysis, which suggests that the underlying mechanism of the nonlinear behavior is associatively governed by the serially connected metallic conductive filament and Flower-Nordheim tunneling barrier formed by the SiO2-x interface layer. The proposed device in this work has great potential to be implemented in future massive storage memory applications of high-density selector-free crossbar structure.

  4. Nonviolent Resistance: A Treatment for Parents of Children with Acute Behavior Problems

    ERIC Educational Resources Information Center

    Weinblatt, Uri; Omer, Haim

    2008-01-01

    Nonviolent resistance (NVR) is a new training model aimed at helping parents deal effectively with their helplessness, isolation, and escalatory interactions with their children. The purpose of this study is to evaluate training in NVR with the parents of children with acute behavior problems. Seventy-three parents (41 families) were randomly…

  5. Predicting Aerobic versus Resistance Exercise Using the Theory of Planned Behavior.

    ERIC Educational Resources Information Center

    Bryan, Angela D.; Rocheleau, Courtney A.

    2002-01-01

    Tested the theory of planned behavior (TPB) in aerobic versus resistance training, investigating relationships between TPB variables, extroversion, and perceived health among college students who completed initial and follow-up measurements and provided reasons for exercise. TPB variables, extroversion, and perceived health collectively accounted…

  6. Nonviolent Resistance: A Treatment for Parents of Children with Acute Behavior Problems

    ERIC Educational Resources Information Center

    Weinblatt, Uri; Omer, Haim

    2008-01-01

    Nonviolent resistance (NVR) is a new training model aimed at helping parents deal effectively with their helplessness, isolation, and escalatory interactions with their children. The purpose of this study is to evaluate training in NVR with the parents of children with acute behavior problems. Seventy-three parents (41 families) were randomly…

  7. Resistance to Change: Overcoming Institutional and Individual Limitations for Improving Student Behavior through PLCs

    ERIC Educational Resources Information Center

    Maag, John W.

    2009-01-01

    Many public schools currently have organizational structures that form barriers for dealing more effectively with students' challenging behaviors even though positive school-wide approaches exist and provide empirical support for their use. Nevertheless, resistance to change occurs at both institutional and individual levels. Improving student…

  8. Phase transformation induced resistive switching behavior in Al/Cu2Se/Pt

    NASA Astrophysics Data System (ADS)

    Rehman, Shania; Kim, Kihwan; Hur, Ji-Hyun; Kim, Deok-kee

    2017-04-01

    The phase transformation induced resistive switching behavior of an Al/Cu2Se/Pt device was studied. While the device did not demonstrate any resistive switching behavior at room temperature, it exhibited resistive switching behavior at 125 °C, near the transition temperature of copper(I) selenide (Cu2Se) (137 °C), where Cu2Se is known to transform from the monoclinic to superionic phase. The increase in ionic conductivity and structural variations (from ordered to disordered structure) associated with phase transformation were observed to be responsible for the origin of the switching behavior and increase in the on/off resistance ratio near the transition temperature. Thermodynamic calculations showed that a reduction in Gibb’s free energy of nucleation and an increase in the migration speed of the Cu ion associated with the ionic conductivity and order to disorder the transition of the Cu2Se at the transition temperature were the important factors responsible for the reduction in the SET voltages at 155 °C.

  9. Individual Differences in Resistance-to-Temptation Behavior in Adolescents: An Eysenck Analysis.

    ERIC Educational Resources Information Center

    LaVoie, Joseph C.

    Eysenck's theory that variations in resistance-to-temptation (i.e., RTT) behavior are contingent on 2 basic personality dimensions -- introversion-extroversion and neuroticism -- which produce differences in conditionability was evaluated in a punishment paradigm with adolescent boys. Measures of manifest anxiety, self-control, and…

  10. Predicting Aerobic versus Resistance Exercise Using the Theory of Planned Behavior.

    ERIC Educational Resources Information Center

    Bryan, Angela D.; Rocheleau, Courtney A.

    2002-01-01

    Tested the theory of planned behavior (TPB) in aerobic versus resistance training, investigating relationships between TPB variables, extroversion, and perceived health among college students who completed initial and follow-up measurements and provided reasons for exercise. TPB variables, extroversion, and perceived health collectively accounted…

  11. Effects of Electrodes on the Switching Behavior of Strontium Titanate Nickelate Resistive Random Access Memory

    PubMed Central

    Lee, Ke-Jing; Wang, Li-Wen; Chiang, Te-Kung; Wang, Yeong-Her

    2015-01-01

    Strontium titanate nickelate (STN) thin films on indium tin oxide (ITO)/glass substrate were synthesized using the sol-gel method for resistive random access memory (RRAM) applications. Aluminum (Al), titanium (Ti), tungsten (W), gold (Au) and platinum (Pt) were used as top electrodes in the STN-based RRAM to probe the switching behavior. The bipolar resistive switching behavior of the set and reset voltages is in opposite bias in the Al/STN/ITO and Pt/STN/ITO RRAMs, which can be partly ascribed to the different work functions of top electrodes in the ITO. Analyses of the fitting results and temperature-dependent performances showed that the Al/STN/ITO switching was mainly attributed to the absorption/release of oxygen-based functional groups, whereas the Pt/STN/ITO switching can be associated with the diffusion of metal electrode ions. The Al/STN/ITO RRAM demonstrated a high resistance ratio of >106 between the high-resistance state (HRS) and the low-resistance state (LRS), as well as a retention ability of >105 s. Furthermore, the Pt/STN/ITO RRAM displayed a HRS/LRS resistance ratio of >103 and a retention ability of >105 s. PMID:28793630

  12. Understanding high-risk behavior among non-dominant minorities: a social resistance framework.

    PubMed

    Factor, Roni; Kawachi, Ichiro; Williams, David R

    2011-11-01

    Across different societies, non-dominant minority groups, compared to the dominant group, often exhibit higher rates of involvement in high-risk behaviors, such as smoking, drug and alcohol use, sexual risk behaviors, overeating, and unsafe driving habits. In turn, these behaviors have a well-documented impact on chronic disease, morbidity, and mortality. Previous studies have emphasized macro-structural or micro-agentic explanations for this phenomenon. Such explanations suffer from mirror-image shortcomings, such as, by emphasizing structural barriers, macro-level explanations leave out individual agency ("the over-socialized conception of the individual"), while micro-level theories give short shrift to structural constraints that prevent individuals from engaging in health-promoting behaviors ("the under-socialized conception of the individual"). Moreover, most current theories regard individuals as passive players who are influenced by the social environment or by psychological problems, or who make "bad" choices. The current paper develops an integrated theoretical framework that incorporates structural inequalities while leaving intact the role of individual agency. According to the social resistance framework, power relations in society encourage members of non-dominant minority groups to actively engage in everyday resistance practices that include various unhealthy behaviors. The paper develops propositions from which testable hypotheses can be generated, and discusses the implications and contributions of the social resistance framework. Copyright © 2011 Elsevier Ltd. All rights reserved.

  13. Interaction of Temperamental Resistance to Control and Restrictive Parenting in the Development of Externalizing Behavior

    PubMed Central

    Bates, John E.; Pettit, Gregory S.; Dodge, Kenneth A.; Ridge, Beth

    2009-01-01

    Child temperament and parental control were studied as interacting predictors of behavior outcomes in 2 longitudinal samples. In Sample 1, data were ratings of resistant temperament and observed restrictive control in infancy–toddlerhood and ratings of externalizing behavior at ages 7 to 10 years; in Sample 2, data were retrospective ratings of temperament in infancy–toddlerhood, observed restrictive control at age 5 years, and ratings of externalizing behavior as ages 7 to 11 years. Resistance more strongly related to externalizing in low-restriction groups than in high-restriction groups. This was true in both samples and for both teacher- and mother-rated outcomes. Several Temperament × Environment interaction effects have been reported previously, but this is one of very few replicated effects. PMID:9779744

  14. Reentrant Resistive Behavior and Dimensional Crossover in Disordered Superconducting TiN Films.

    PubMed

    Postolova, Svetlana V; Mironov, Alexey Yu; Baklanov, Mikhail R; Vinokur, Valerii M; Baturina, Tatyana I

    2017-05-11

    A reentrant temperature dependence of the normal state resistance often referred to as the N-shaped temperature dependence, is omnipresent in disordered superconductors - ranging from high-temperature cuprates to ultrathin superconducting films - that experience superconductor-to-insulator transition. Yet, despite the ubiquity of this phenomenon its origin still remains a subject of debate. Here we investigate strongly disordered superconducting TiN films and demonstrate universality of the reentrant behavior. We offer a quantitative description of the N-shaped resistance curve. We show that upon cooling down the resistance first decreases linearly with temperature and then passes through the minimum that marks the 3D-2D crossover in the system. In the 2D temperature range the resistance first grows with decreasing temperature due to quantum contributions and eventually drops to zero as the system falls into a superconducting state. Our findings demonstrate the prime importance of disorder in dimensional crossover effects.

  15. Behavioral momentum of cocaine self-administration: effects of frequency of reinforcement on resistance to extinction.

    PubMed

    Quick, Stacey L; Shahan, Timothy A

    2009-07-01

    Persistent drug seeking is a defining property of substance abuse and is generally thought to depend, in part, on exposure to drug-associated contexts. Behavioral momentum theory provides a set of methods and a theoretical framework for understanding how stimulus contexts contribute to the persistence of operant behavior. Earlier research has extended behavioral momentum theory to alcohol self-administration, but not to intravenous drug self-administration. This experiment extended behavioral momentum theory to cocaine self-administration by examining the effects of frequency of cocaine reinforcement in a context on resistance to extinction. Rats self-administered 0.32 mg/kg infusions of cocaine in a multiple schedule of reinforcement arranging two distinct contexts. Responding in a Rich context was reinforced by cocaine infusions at a higher frequency (i.e. variable interval 120 s) and in a Lean context at a lower frequency (variable interval 360 s). After establishment of responding in the two contexts, resistance to extinction was examined. Preextinction response rates for cocaine were similar in the Rich and Lean contexts. Nonetheless, relative resistance to extinction was greater in the Rich context than in the Lean context. The difference in resistance to extinction in the two contexts was well described by a quantitative model of behavioral momentum. These results suggest that the frequency of drug reinforcement in a context contributes to the persistence of drug seeking in that context, and that behavioral momentum theory might be useful for understanding how drug-associated contexts contribute to the persistence of drug seeking.

  16. Reducing care-resistant behaviors during oral hygiene in persons with dementia

    PubMed Central

    2011-01-01

    Background Nursing home residents with dementia are often dependent on others for mouth care, yet will react with care-resistant behavior when receiving assistance. The oral health of these elders deteriorates in the absence of daily oral hygiene, predisposing them to harmful systemic problems such as pneumonia, hyperglycemia, cardiac disease, and cerebral vascular accidents. The purpose of this study is to determine whether care-resistant behaviors can be reduced, and oral health improved, through the application of an intervention based on the neurobiological principles of threat perception and fear response. The intervention, called Managing Oral Hygiene Using Threat Reduction, combines best mouth care practices with a constellation of behavioral techniques that reduce threat perception and thereby prevent or de-escalate care-resistant behaviors. Methods/Design Using a randomized repeated measures design, 80 elders with dementia from 5 different nursing homes will be randomized at the individual level to the experimental group, which will receive the intervention, or to the control group, which will receive standard mouth care from research team members who receive training in the proper methods for providing mouth care but no training in resistance recognition or prevention/mediation. Oral health assessments and care-resistant behavior measurements will be obtained during a 7-day observation period and a 21-day intervention period. Individual growth models using multilevel analysis will be used to estimate the efficacy of the intervention for reducing care-resistant behaviors in persons with dementia, and to estimate the overall efficacy of the intervention using oral health outcomes. Activity-based costing methods will be used to determine the cost of the proposed intervention. Discussion At the conclusion of this study, the research team anticipates having a proven intervention that prevents and reduces care-resistant within the context of mouth care. Long

  17. Reducing care-resistant behaviors during oral hygiene in persons with dementia.

    PubMed

    Jablonski, Rita A; Kolanowski, Ann; Therrien, Barbara; Mahoney, Ellen K; Kassab, Cathy; Leslie, Douglas L

    2011-11-19

    Nursing home residents with dementia are often dependent on others for mouth care, yet will react with care-resistant behavior when receiving assistance. The oral health of these elders deteriorates in the absence of daily oral hygiene, predisposing them to harmful systemic problems such as pneumonia, hyperglycemia, cardiac disease, and cerebral vascular accidents. The purpose of this study is to determine whether care-resistant behaviors can be reduced, and oral health improved, through the application of an intervention based on the neurobiological principles of threat perception and fear response. The intervention, called Managing Oral Hygiene Using Threat Reduction, combines best mouth care practices with a constellation of behavioral techniques that reduce threat perception and thereby prevent or de-escalate care-resistant behaviors. Using a randomized repeated measures design, 80 elders with dementia from 5 different nursing homes will be randomized at the individual level to the experimental group, which will receive the intervention, or to the control group, which will receive standard mouth care from research team members who receive training in the proper methods for providing mouth care but no training in resistance recognition or prevention/mediation. Oral health assessments and care-resistant behavior measurements will be obtained during a 7-day observation period and a 21-day intervention period. Individual growth models using multilevel analysis will be used to estimate the efficacy of the intervention for reducing care-resistant behaviors in persons with dementia, and to estimate the overall efficacy of the intervention using oral health outcomes. Activity-based costing methods will be used to determine the cost of the proposed intervention. At the conclusion of this study, the research team anticipates having a proven intervention that prevents and reduces care-resistant within the context of mouth care. Long-term objectives include testing the

  18. Independent behavior of commensal flora for carriage of fluoroquinolone-resistant bacteria in patients at admission.

    PubMed

    de Lastours, Victoire; Chau, Françoise; Tubach, Florence; Pasquet, Blandine; Ruppé, Etienne; Fantin, Bruno

    2010-12-01

    The important role of commensal flora as a natural reservoir of bacterial resistance is now well established. However, whether the behavior of each commensal flora is similar to that of other floras in terms of rates of carriage and risk factors for bacterial resistance is unknown. During a 6-month period, we prospectively investigated colonization with fluoroquinolone-resistant bacteria in the three main commensal floras from hospitalized patients at admission, targeting Escherichia coli in the fecal flora, coagulase-negative Staphylococcus (CNS) in the nasal flora, and α-hemolytic streptococci in the pharyngeal flora. Resistant strains were detected on quinolone-containing selective agar. Clinical and epidemiological data were collected. A total of 555 patients were included. Carriage rates of resistance were 8.0% in E. coli, 30.3% in CNS for ciprofloxacin, and 27.2% in streptococci for levofloxacin; 56% of the patients carried resistance in at least one flora but only 0.9% simultaneously in all floras, which is no more than random. Risk factors associated with the carriage of fluoroquinolone-resistant strains differed between fecal E. coli (i.e., colonization by multidrug-resistant bacteria) and nasal CNS (i.e., age, coming from a health care facility, and previous antibiotic treatment with a fluoroquinolone) while no risk factors were identified for pharyngeal streptococci. Despite high rates of colonization with fluoroquinolone-resistant bacteria, each commensal flora behaved independently since simultaneous carriage of resistance in the three distinct floras was uncommon, and risk factors differed. Consequences of environmental selective pressures vary in each commensal flora according to its local specificities (clinical trial NCT00520715 [http://clinicaltrials.gov/ct2/show/NCT00520715]).

  19. The use of cognitive behavioral therapy in the treatment of resistant depression in adolescents

    PubMed Central

    Hamill-Skoch, Sarah; Hicks, Paul; Prieto-Hicks, Ximena

    2012-01-01

    Major depressive disorder often begins in adolescence, is chronic and recurrent, and heightens an individual’s risk for major depressive disorder in adulthood. Treatment-resistant depression is a problem for a significant minority of adolescents. Few studies have examined treatments for treatment-resistant depression among adolescents, and even fewer have examined the use of cognitive-behavioral therapy as a monotherapy or in combination with pharmacological treatments. Mental health professionals have a strong interest in understanding what treatments are appropriate for adolescents who are treatment resistant. Preliminary evidence from current published trials indicates that the use of cognitive-behavioral therapy in combination with antidepressant medication yields the best outcome for treatment-resistant depression in adolescents. Secondary analyses also suggest that the utility of cognitive behavioral therapy can be increased by ensuring adolescents receive a therapeutic dose of treatment sessions (more than nine sessions) and the inclusion of two treatment components: social skills and problem solving training. Guidelines for clinicians as well as areas for future research are discussed. PMID:24600290

  20. Abnormal resistivity behavior of Cu-Ni and Cu-Co alloys in undercooled liquid state

    NASA Astrophysics Data System (ADS)

    Guo, Fengxiang; Lu, Ting; Qin, Jingyu; Zheng, Hongliang; Tian, Xuelei

    2012-11-01

    The resistivity behavior of undercooled liquid Cu-Ni and Cu-Co alloys had been studied in the contactless method, to probe the structure transition in undercooled melts during the cooling process. Over the entire concentration range, linear behavior of resistivity with temperature was obtained in liquid and undercooled liquid Cu-Ni system. It implied that the formation of icosahedral order might not influence the electron scattering in undercooled liquid Cu-Ni alloys. Similar results were obtained in Cu-Co system in the vicinity of liquidus temperature. A turning point was obvious in temperature coefficient of resistivity for undercooled liquid Cu-Co alloys around the bimodal line, which was interpreted to be responsible for metastable liquid-liquid phase separation. During liquid phase separation process, resistivity decreased and the temperature coefficient of resistivity was larger than that of homogeneous melts. In combination with transmission electron microscopy and scanning electron microscope studies on the as-solidified microstructure, this was interpreted as the formation of egg-type structure and concentration change in Cu-rich and Co-rich phases. The mechanism controlling the separation and droplets motion was also discussed in undercooled liquid Cu-Co system.

  1. Social Resistance Framework for Understanding High-Risk Behavior Among Nondominant Minorities: Preliminary Evidence

    PubMed Central

    Williams, David R.; Kawachi, Ichiro

    2013-01-01

    Objectives. The recently developed social resistance framework addresses a widespread pattern in which members of some nondominant minorities tend to engage in various risky and unhealthy behaviors more than the majority group. This pilot study tested the core hypotheses derived from this innovative framework. Methods. We conducted in 2011 a nationally representative Web-based survey of 200 members of a nondominant minority group (African Americans) and 200 members of a majority group (Whites). Results. The preliminary findings supported the main premises of the framework and suggested that nondominant minorities who felt discriminated and alienated from society tended also to have higher levels of social resistance. Those with higher levels of social resistance also engaged more in risky and unhealthy behaviors—smoking, drinking, and nonuse of seat belts—than did those with lower levels of social resistance. These associations were not found in the majority group. Conclusions. These preliminary results supported the framework and suggested that social resistance might play a meaningful role in risky and unhealthy behaviors of nondominant minorities, and should be taken into account when trying to reduce health disparities. PMID:23597381

  2. Unique Behavioral Characteristics and microRNA Signatures in a Drug Resistant Epilepsy Model

    PubMed Central

    Jung, Keun-Hwa; Yang, Hyunwoo; Khalid, Arshi; Kim, Jeong-Min; Park, Kyung-Il; Shin, Jung-Won; Ban, Jae-Jun; Yi, Gwan-Su; Lee, Sang Kun; Jeon, Daejong; Chu, Kon

    2014-01-01

    Background Pharmacoresistance is a major issue in the treatment of epilepsy. However, the mechanism underlying pharmacoresistance to antiepileptic drugs (AEDs) is still unclear, and few animal models have been established for studying drug resistant epilepsy (DRE). In our study, spontaneous recurrent seizures (SRSs) were investigated by video-EEG monitoring during the entire procedure. Methods/Principal Findings In the mouse pilocarpine-induced epilepsy model, we administered levetiracetam (LEV) and valproate (VPA) in sequence. AED-responsive and AED-resistant mice were naturally selected after 7-day treatment of LEV and VPA. Behavioral tests (open field, object exploration, elevated plus maze, and light-dark transition test) and a microRNA microarray test were performed. Among the 37 epileptic mice with SRS, 23 showed significantly fewer SRSs during administration of LEV (n = 16, LEV sensitive (LS) group) or VPA (n = 7, LEV resistant/VPA sensitive (LRVS) group), while 7 epileptic mice did not show any amelioration with either of the AEDs (n = 7, multidrug resistant (MDR) group). On the behavioral assessment, MDR mice displayed distinctive behaviors in the object exploration and elevated plus maze tests, which were not observed in the LS group. Expression of miRNA was altered in LS and MDR groups, and we identified 4 miRNAs (miR-206, miR-374, miR-468, and miR-142-5p), which were differently modulated in the MDR group versus both control and LS groups. Conclusion This is the first study to identify a pharmacoresistant subgroup, resistant to 2 AEDs, in the pilocarpine-induced epilepsy model. We hypothesize that modulation of the identified miRNAs may play a key role in developing pharmacoresistance and behavioral alterations in the MDR group. PMID:24454901

  3. Pulse widths dependence of programming and erasing behaviors for diamond like carbon based resistive switching memories

    NASA Astrophysics Data System (ADS)

    Xu, Jianlong; Xie, Dan; Zhang, Chenhui; Zhang, Xiaowen; Peng, Pinggang; Fu, Di; Qian, He; Ren, Tian-ling; Liu, Litian

    2014-10-01

    We report the influences of pulse widths on the programming and erasing characteristics of diamond-like carbon films based resistive random access memory. The device can be only programmed with pulses wider than 50 ns for SET operations when the pulse voltage is 1.2 V and erased with pulses narrower than 25 ns for RESET operations when the pulse voltage is 0.4 V. The formation, rupture, and re-growth of the conductive sp2-like graphitic filaments are proposed to be responsible for the resistive switching behaviors, based on which the pulse widths dependences on its programming and erasing properties can be further explained.

  4. Effect of chromium doping on the resistivity behavior of gadolinium manganite

    NASA Astrophysics Data System (ADS)

    Modi, Anchit; Thakur, Rajesh K.; Thakur, Rasna; Okram, G. S.; Gaur, N. K.

    2013-02-01

    Systematic investigation of structure and resistivity behaviour of GdMnO3 with 20% Cr doping has been undertaken that papered by conventional solid state reaction method. Upon Cr doping on the Mn site the lattice parameters and unit cell volume were reduced due to slight difference between the ionic radii of Cr3+ and Mn3+ compare with Pure GdMnO3 (according to JCPDS: 25-0337). The Cr-doped manganites exhibit a large variation in resistivity values. Cr3+ doping makes the material to exhibit a semiconductor behavior, for which the electronic transport can be explained by small polaron hopping (SPH) model.

  5. Behavior patterns of cold-resistant golden spiny mouse Acomys russatus.

    PubMed

    Haim, A

    1991-09-01

    Nesting behavior and food storage were studied in a cold-resistant (CR) population of the golden spiny mouse, Acomys russatus, in Southern Sinai at an altitude of 1600 m. CR-mice, in contrast to cold-sensitive (CS) ones, built nests in which they stored food. Such mice were found to be winter-solitary. These results show that food supply is an essential parameter for the survival of CR-mice during winter. Therefore, it is suggested that food supply rather than energy conservation was the main driving force in the selection of a solitary behavior pattern of CR-mice.

  6. Resistive-switching behavior in polycrystalline CaCu(3)Ti(4)O(12) nanorods.

    PubMed

    Tararam, R; Joanni, E; Savu, R; Bueno, P R; Longo, E; Varela, J A

    2011-02-01

    Highly aligned CaCu(3)Ti(4)O(12) nanorod arrays were grown on Si/SiO(2)/Ti/Pt substrates by radio-frequency sputtering at a low deposition temperature of 300 °C and room temperature. Structural and morphological studies have shown that the nanostructures have a polycrystalline nature and are oriented perpendicular to the substrate. The high density of grain boundaries in the nanorods is responsible for the nonlinear current behavior observed in these arrays. The current-voltage (I-V) characteristics observed in nanorods were attributed to the resistive memory phenomenon. The electrical resistance of microcapacitors composed of CaCu(3)Ti(4)O(12) nanorods could be reversibly switched between two stable resistance states by varying the applied electric field. In order to explain this switching mechanism, a model based on the increase/decrease of electrical conduction controlled by grain boundary polarization has been proposed.

  7. Critical behavior of the resistivity of GaMnAs near the Curie temperature

    NASA Astrophysics Data System (ADS)

    Yuldashev, Sh. U.; Yunusov, Z. A.; Kwon, Y. H.; Lee, S. H.; Ahuja, R.; Kang, T. W.

    2017-09-01

    The effect of the magnetization fluctuations on the resistivity of GaMnAs near the Curie temperature TC was experimentally studied. It is shown that the determination of TC from the maximum of the temperature derivative of the resistivity is valid for the samples with a high concentration of free carries. Whereas, for the samples with low concentration of free carriers the TC coincides with the resistivity maximum. The magnetic specific heat for T>TC demonstrates the crossover from the one dimensional to the three dimensional critical behavior when the temperature become closer to the Curie temperature. This is explained by the formation of the ferromagnetic phase in the paramagnetic side of the phase transition which is started from Mn-Mn dimers oriented along one direction.

  8. Sub-10 nm low current resistive switching behavior in hafnium oxide stack

    SciTech Connect

    Hou, Y. E-mail: lfliu@pku.edu.cn; Celano, U.; Xu, Z.; Vandervorst, W.; Goux, L.; Fantini, A.; Degraeve, R.; Youssef, A.; Jurczak, M.; Liu, L. E-mail: lfliu@pku.edu.cn; Cheng, Y.; Kang, J.

    2016-03-21

    In this letter, a tip-induced cell relying on the conductive atomic force microscope is proposed. It is verified as a referable replica of an integrated resistive random access memory (RRAM) device. On the basis of this cell, the functionality of sub-10 nm resistive switching is confirmed in hafnium oxide stack. Moreover, the low current switching behavior in the sub-10 nm dimension is found to be more pronounced than that of a 50 × 50 nm{sup 2} device. It shows better ON/OFF ratio and low leakage current. The enhanced memory performance is ascribed to a change in the shape of the conductive filament as the device dimensions are reduced to sub-10 nm. Therefore, device downscaling provides a promising approach for the resistance optimization that benefits the RRAM array design.

  9. Therapist awareness of client resistance in cognitive-behavioral therapy for generalized anxiety disorder.

    PubMed

    Hara, Kimberley M; Westra, Henny A; Aviram, Adi; Button, Melissa L; Constantino, Michael J; Antony, Martin M

    2015-01-01

    Clients' resistance relates negatively to their retention and outcomes in psychotherapy; thus, it has been increasingly identified as a key process marker in both research and practice. This study compared therapists' postsession ratings of resistance with those of trained observers in the context of 40 therapist-client dyads receiving 15 sessions of cognitive-behavioral therapy for generalized anxiety disorder. Therapist and observer ratings were then examined as correlates of proximal (therapeutic alliance quality and homework compliance) and distal (posttreatment worry severity) outcomes. Although there was reasonable concordance between rater perspectives, observer ratings were highly and consistently related to both proximal and distal outcomes, while therapist ratings were not. These findings underscore the need to enhance therapists' proficiency in identifying important and often covert in-session clinical phenomena such as the cues reflecting resistance and noncollaboration.

  10. Fretting Wear Behavior of Tin Plated Contacts:. Influence on Contact Resistance

    NASA Astrophysics Data System (ADS)

    Park, Young Woo; Sankara Narayanan, T. S. N.; Lee, Kang Yong

    The fretting wear behavior of tin plated copper alloy contacts and its influence on the contact resistance are addressed in this paper. Based on the change in the area of contact zone as well as the wear depth as a function of fretting cycles, a model was proposed to explain the observed low and stable contact resistance. The extent of wear of tin coating and the formation of wear debris as a function of fretting cycles were assessed by scanning electron microscopy (SEM). Energy dispersive X-ray line scanning (EDX), X-ray mapping, and EDX spot analysis were employed to characterize the nature of changes that occur at the contact zone. The study reveals that the fretted area increases linearly up to 8000 cycles due to the continuous removal of the tin coating and attains saturation when the fretting path length reaches a maximum. The observed low and stable contact resistance observed up to 8000 cycles is due to the common area of contact which provides an electrically conducting area. Surface analysis by SEM, EDX, and X-ray elemental mapping elucidate the nature of changes that occurred at the contact zone. Based on the change in contact resistance as a function of fretting cycles, the fretting wear and fretting corrosion dominant regimes are proposed. The interdependence of extent of wear and oxidation increases the complexity of the fretting corrosion behavior of tin plated contacts.

  11. Resistant Starch Alters the Microbiota-Gut Brain Axis: Implications for Dietary Modulation of Behavior.

    PubMed

    Lyte, Mark; Chapel, Ashley; Lyte, Joshua M; Ai, Yongfeng; Proctor, Alexandra; Jane, Jay-Lin; Phillips, Gregory J

    2016-01-01

    The increasing recognition that the gut microbiota plays a central role in behavior and cognition suggests that the manipulation of microbial taxa through diet may provide a means by which behavior may be altered in a reproducible and consistent manner in order to achieve a beneficial outcome for the host. Resistant starch continues to receive attention as a dietary intervention that can benefit the host through mechanisms that include altering the intestinal microbiota. Given the interest in dietary approaches to improve health, the aim of this study was to investigate whether the use of dietary resistant starch in mice to alter the gut microbiota also results in a change in behavior. Forty-eight 6 week-old male Swiss-Webster mice were randomly assigned to 3 treatment groups (n = 16 per group) and fed either a normal corn starch diet (NCS) or diets rich in resistant starches HA7 diet (HA7) or octenyl-succinate HA7 diet (OS-HA7) for 6 week and monitored for weight, behavior and fecal microbiota composition. Animals fed an HA7 diet displayed comparable weight gain over the feeding period to that recorded for NCS-fed animals while OS-HA7 displayed a lower weight gain as compared to either NCS or HA7 animals (ANOVA p = 0.0001; NCS:HA7 p = 0.244; HA7:OS-HA7 p<0.0001; NCS:OS-HA7 p<0.0001). Analysis of fecal microbiota using 16s rRNA gene taxonomic profiling revealed that each diet corresponded with a unique gut microbiota. The distribution of taxonomic classes was dynamic over the 6 week feeding period for each of the diets. At the end of the feeding periods, the distribution of taxa included statistically significant increases in members of the phylum Proteobacteria in OS-HA7 fed mice, while the Verrucomicrobia increased in HA7 fed mice over that of mice fed OS-HA7. At the class level, members of the class Bacilli decreased in the OS-HA7 fed group, and Actinobacteria, which includes the genus Bifidobacteria, was enriched in the HA7 fed group compared to the control

  12. Resistant Starch Alters the Microbiota-Gut Brain Axis: Implications for Dietary Modulation of Behavior

    PubMed Central

    Lyte, Mark; Chapel, Ashley; Lyte, Joshua M.; Ai, Yongfeng; Proctor, Alexandra; Jane, Jay-Lin; Phillips, Gregory J.

    2016-01-01

    The increasing recognition that the gut microbiota plays a central role in behavior and cognition suggests that the manipulation of microbial taxa through diet may provide a means by which behavior may be altered in a reproducible and consistent manner in order to achieve a beneficial outcome for the host. Resistant starch continues to receive attention as a dietary intervention that can benefit the host through mechanisms that include altering the intestinal microbiota. Given the interest in dietary approaches to improve health, the aim of this study was to investigate whether the use of dietary resistant starch in mice to alter the gut microbiota also results in a change in behavior. Forty-eight 6 week-old male Swiss-Webster mice were randomly assigned to 3 treatment groups (n = 16 per group) and fed either a normal corn starch diet (NCS) or diets rich in resistant starches HA7 diet (HA7) or octenyl-succinate HA7 diet (OS-HA7) for 6 week and monitored for weight, behavior and fecal microbiota composition. Animals fed an HA7 diet displayed comparable weight gain over the feeding period to that recorded for NCS-fed animals while OS-HA7 displayed a lower weight gain as compared to either NCS or HA7 animals (ANOVA p = 0.0001; NCS:HA7 p = 0.244; HA7:OS-HA7 p<0.0001; NCS:OS-HA7 p<0.0001). Analysis of fecal microbiota using 16s rRNA gene taxonomic profiling revealed that each diet corresponded with a unique gut microbiota. The distribution of taxonomic classes was dynamic over the 6 week feeding period for each of the diets. At the end of the feeding periods, the distribution of taxa included statistically significant increases in members of the phylum Proteobacteria in OS-HA7 fed mice, while the Verrucomicrobia increased in HA7 fed mice over that of mice fed OS-HA7. At the class level, members of the class Bacilli decreased in the OS-HA7 fed group, and Actinobacteria, which includes the genus Bifidobacteria, was enriched in the HA7 fed group compared to the control

  13. Demonstration of Synaptic Behaviors and Resistive Switching Characterizations by Proton Exchange Reactions in Silicon Oxide

    NASA Astrophysics Data System (ADS)

    Chang, Yao-Feng; Fowler, Burt; Chen, Ying-Chen; Zhou, Fei; Pan, Chih-Hung; Chang, Ting-Chang; Lee, Jack C.

    2016-02-01

    We realize a device with biological synaptic behaviors by integrating silicon oxide (SiOx) resistive switching memory with Si diodes. Minimal synaptic power consumption due to sneak-path current is achieved and the capability for spike-induced synaptic behaviors is demonstrated, representing critical milestones for the use of SiO2–based materials in future neuromorphic computing applications. Biological synaptic behaviors such as long-term potentiation (LTP), long-term depression (LTD) and spike-timing dependent plasticity (STDP) are demonstrated systematically using a comprehensive analysis of spike-induced waveforms, and represent interesting potential applications for SiOx-based resistive switching materials. The resistive switching SET transition is modeled as hydrogen (proton) release from (SiH)2 to generate the hydrogen bridge defect, and the RESET transition is modeled as an electrochemical reaction (proton capture) that re-forms (SiH)2. The experimental results suggest a simple, robust approach to realize programmable neuromorphic chips compatible with large-scale CMOS manufacturing technology.

  14. Demonstration of Synaptic Behaviors and Resistive Switching Characterizations by Proton Exchange Reactions in Silicon Oxide

    PubMed Central

    Chang, Yao-Feng; Fowler, Burt; Chen, Ying-Chen; Zhou, Fei; Pan, Chih-Hung; Chang, Ting-Chang; Lee, Jack C.

    2016-01-01

    We realize a device with biological synaptic behaviors by integrating silicon oxide (SiOx) resistive switching memory with Si diodes. Minimal synaptic power consumption due to sneak-path current is achieved and the capability for spike-induced synaptic behaviors is demonstrated, representing critical milestones for the use of SiO2–based materials in future neuromorphic computing applications. Biological synaptic behaviors such as long-term potentiation (LTP), long-term depression (LTD) and spike-timing dependent plasticity (STDP) are demonstrated systematically using a comprehensive analysis of spike-induced waveforms, and represent interesting potential applications for SiOx-based resistive switching materials. The resistive switching SET transition is modeled as hydrogen (proton) release from (SiH)2 to generate the hydrogen bridge defect, and the RESET transition is modeled as an electrochemical reaction (proton capture) that re-forms (SiH)2. The experimental results suggest a simple, robust approach to realize programmable neuromorphic chips compatible with large-scale CMOS manufacturing technology. PMID:26880381

  15. Insulin resistance in brain alters dopamine turnover and causes behavioral disorders

    PubMed Central

    Kleinridders, Andre; Cai, Weikang; Cappellucci, Laura; Ghazarian, Armen; Collins, William R.; Vienberg, Sara G.; Pothos, Emmanuel N.; Kahn, C. Ronald

    2015-01-01

    Diabetes and insulin resistance are associated with altered brain imaging, depression, and increased rates of age-related cognitive impairment. Here we demonstrate that mice with a brain-specific knockout of the insulin receptor (NIRKO mice) exhibit brain mitochondrial dysfunction with reduced mitochondrial oxidative activity, increased levels of reactive oxygen species, and increased levels of lipid and protein oxidation in the striatum and nucleus accumbens. NIRKO mice also exhibit increased levels of monoamine oxidase A and B (MAO A and B) leading to increased dopamine turnover in these areas. Studies in cultured neurons and glia cells indicate that these changes in MAO A and B are a direct consequence of loss of insulin signaling. As a result, NIRKO mice develop age-related anxiety and depressive-like behaviors that can be reversed by treatment with MAO inhibitors, as well as the tricyclic antidepressant imipramine, which inhibits MAO activity and reduces oxidative stress. Thus, insulin resistance in brain induces mitochondrial and dopaminergic dysfunction leading to anxiety and depressive-like behaviors, demonstrating a potential molecular link between central insulin resistance and behavioral disorders. PMID:25733901

  16. Nonviolent resistance: a treatment for parents of children with acute behavior problems.

    PubMed

    Weinblatt, Uri; Omer, Haim

    2008-01-01

    Nonviolent resistance (NVR) is a new training model aimed at helping parents deal effectively with their helplessness, isolation, and escalatory interactions with their children. The purpose of this study is to evaluate training in NVR with the parents of children with acute behavior problems. Seventy-three parents (41 families) were randomly assigned to a treatment group and wait-list control group. Measures were taken at pretreatment, posttreatment, and a 1-month follow-up. In comparison with the wait-list group, parents who received training in NVR showed a decrease in parental helplessness and escalatory behaviors, and an increase in perceived social support. The children's negative behaviors as assessed by the parents also decreased significantly.

  17. Multidrug resistance 1 gene polymorphisms may determine Crohn's disease behavior in patients from Rio de Janeiro

    PubMed Central

    Carvalho, Ana Teresa P; Fróes, Renata S B; Esberard, Barbara C; Santos, Juliana C V C; Rapozo, Davy C. M.; Grinman, Ana B; Simão, Tatiana A; Neto, Pedro Nicolau; Luiz, Ronir R; Carneiro, Antonio José V; de Souza, Heitor S P; Ribeiro-Pinto, Luis Felipe

    2014-01-01

    OBJECTIVES: Conflicting data from studies on the potential role of multidrug resistance 1 gene polymorphisms in inflammatory bowel disease may result from the analysis of genetically and geographically distinct populations. Here, we investigated whether multidrug resistance 1 gene polymorphisms are associated with inflammatory bowel diseases in patients from Rio de Janeiro. METHODS: We analyzed 123 Crohn's disease patients and 83 ulcerative colitis patients to determine the presence of the multidrug resistance 1 gene polymorphisms C1236T, G2677T and C3435T. In particular, the genotype frequencies of Crohn's disease and ulcerative colitis patients were analyzed. Genotype-phenotype associations with major clinical characteristics were established, and estimated risks were calculated for the mutations. RESULTS: No significant difference was observed in the genotype frequencies of the multidrug resistance 1 G2677T/A and C3435T polymorphisms between Crohn's disease and ulcerative colitis patients. In contrast, the C1236T polymorphism was significantly more common in Crohn's disease than in ulcerative colitis (p = 0.047). A significant association was also found between the multidrug resistance 1 C3435T polymorphism and the stricturing form of Crohn's disease (OR: 4.13; p = 0.009), whereas no association was found with penetrating behavior (OR: 0.33; p = 0.094). In Crohn's disease, a positive association was also found between the C3435T polymorphism and corticosteroid resistance/refractoriness (OR: 4.14; p = 0.010). However, no significant association was found between multidrug resistance 1 gene polymorphisms and UC subphenotypic categories. CONCLUSION: The multidrug resistance 1 gene polymorphism C3435T is associated with the stricturing phenotype and an inappropriate response to therapy in Crohn's disease. This association with Crohn's disease may support additional pathogenic roles for the multidrug resistance 1 gene in regulating gut

  18. Resistive switching behavior of SiOx layers with Si nanoparticles

    NASA Astrophysics Data System (ADS)

    Nesheva, D.; Pantchev, B.; Nedev, N.; Valdez, B.; Manolov, E.; Dzhurkov, V.; Nedev, R.

    2017-01-01

    First results on resistive switching in SiOx film containing crystalline silicon nanoparticles are reported. SiOx layers (x = 1.15) with thickness of 50 nm were deposited on n-Si crystalline substrates and annealed for 60 min at 1000oC to grow crystalline nanoparticles. Part of the samples were annealed in an inert atmosphere, while the rest were subjected to a two-step (O2+N2/N2) annealing process. Current-voltage (I-V) characteristics were by applying positive or negative voltage to the top contact. For both types of samples the I-V characteristics were asymmetric with lower currents measured at negative voltage, especially in the case of two-step annealed samples. In most of the N2 annealed structures switching behavior high-low/low-high resistance state was observed in both polarities at voltages with amplitudes in the range (2 - 4) V. Uncontrolled switching low/high resistance was also seen, more frequently at positive voltages. In contrast, the two-step annealed samples showed stable behavior. The transition high-low resistance state was achieved by negative voltages in the (-2, -5) V range leading to an increase of the current by more than three orders of magnitude. The structures were reset to the high resistive state, by positive voltage in the range (3 - 4) V. Uncontrolled switching was not observed in the two-step annealed samples for both polarities and they showed higher reliability regarding the number of switching cycles.

  19. Multi-step resistive switching behavior of Li-doped ZnO resistance random access memory device controlled by compliance current

    SciTech Connect

    Lin, Chun-Cheng; Tang, Jian-Fu; Su, Hsiu-Hsien; Hong, Cheng-Shong; Huang, Chih-Yu; Chu, Sheng-Yuan

    2016-06-28

    The multi-step resistive switching (RS) behavior of a unipolar Pt/Li{sub 0.06}Zn{sub 0.94}O/Pt resistive random access memory (RRAM) device is investigated. It is found that the RRAM device exhibits normal, 2-, 3-, and 4-step RESET behaviors under different compliance currents. The transport mechanism within the device is investigated by means of current-voltage curves, in-situ transmission electron microscopy, and electrochemical impedance spectroscopy. It is shown that the ion transport mechanism is dominated by Ohmic behavior under low electric fields and the Poole-Frenkel emission effect (normal RS behavior) or Li{sup +} ion diffusion (2-, 3-, and 4-step RESET behaviors) under high electric fields.

  20. Nonvolatile conductive filaments resistive switching behaviors in Ag/GaO x /Nb:SrTiO3/Ag structure

    NASA Astrophysics Data System (ADS)

    Li, P. G.; Zhi, Y. S.; Wang, P. C.; Sun, Z. B.; Li, L. H.; An, Y. H.; Guo, D. Y.; Tang, W. H.; Xiao, J. H.

    2016-07-01

    Ag/GaO x /NSTO/Ag structures were fabricated, and the electrical properties measurement results show that the device behaviors a unipolar resistance switching characteristic with bi-stable resistance ratio of three orders. In the positive voltage region, the dominant conducting mechanism of high resistance state obeys Poole-Frenkel emission rules, while in the negative region, that obeys space-charge-limited current mechanism. Both the I- V curves of ON and OFF states and temperature-dependent variation resistances indicate that the unipolar resistance switching behavior can be explained by the formation/rupture of conductive filaments, which composed of oxygen vacancies. The stable switching results demonstrated that the structure can be applied in resistance random access memory devices.

  1. Pyrethroid resistance alters the blood-feeding behavior in Puerto Rican Aedes aegypti mosquitoes exposed to treated fabric.

    PubMed

    Agramonte, Natasha M; Bloomquist, Jeffrey R; Bernier, Ulrich R

    2017-09-01

    Emerging insecticide resistance is a major issue for vector control. It decreases the effectiveness of insecticides, thereby requiring greater quantities for comparable control with a net increase in risk of disease resurgence, product cost, and damage risk to the ecosystem. Pyrethroid resistance has been documented in Puerto Rican populations of Aedes aegypti (L.) mosquitoes. In this study, topical toxicity of five insecticides (permethrin, etofenprox, deltamethrin, DDT, transfluthrin) was determined for susceptible (Orlando-ORL) and resistant (Puerto Rico-PR) strains of Ae. aegypti. Resistance ratios were calculated using LD50 values, and high resistance ratios for permethrin (112) and etofenprox (228) were observed for the Puerto Rico strain. Behavioral differences in blood-feeding activity for pyrethroid-resistant and pyrethroid-susceptible strains of Ae. aegypti when exposed to pyrethroid-treated cloth were also explored. Strains were exposed for 15 min to a range of concentrations of pyrethroid-treated uniform fabric in a cage that contained 60 female Ae. aegypti mosquitoes. Interestingly, the resistance ratios for blood-feeding were similar for permethrin (61) and etofenprox (70), but were lower than their respective resistance ratios for topical toxicity, suggesting that knockdown resistance was the primary mechanism of resistance in the blood feeding assays. Results showed a rightward shift in the dose-response curves for blood-feeding that indicated higher concentrations of pyrethroids were necessary to deter blood-feeding behavior in the pyrethroid-resistant Puerto Rican strain of Ae. aegypti.

  2. Recrystallization behavior of Ti40 burn-resistant titanium alloy during hot working process

    NASA Astrophysics Data System (ADS)

    Lai, Yun-jin; Xin, She-wei; Zhang, Ping-xiang; Zhao, Yong-qing; Ma, Fan-jiao; Liu, Xiang-hong; Feng, Yong

    2016-05-01

    The recrystallization behavior of deformed Ti40 alloy during a heat-treatment process was studied using electron backscatter diffraction and optical microscopy. The results show that the microstructural evolution of Ti40 alloy is controlled by the growth behavior of grain-boundary small grains during the heating process. These small grains at the grain boundaries mostly originate during the forging process because of the alloy's inhomogeneous deformation. During forging, the deformation first occurs in the grain-boundary region. New small recrystallized grains are separated from the parent grains when the orientation between deformation zones and parent grains exceeds a certain threshold. During the heating process, the growth of these small recrystallized grains results in a uniform grain size and a decrease in the average grain size. The special recrystallization behavior of Ti40 alloy is mainly a consequence of the alloy's high β-stabilized elemental content and high solution strength of the β-grains, which partially explains the poor hot working ability of Ti-V-Cr-type burn-resistant titanium alloys. Notably, this study on Ti40 burn-resistant titanium alloy yields important information related to the optimization of the microstructures and mechanical properties.

  3. Reentrant resistive behavior and dimensional crossover in disordered superconducting TiN films

    DOE PAGES

    Postolova, Svetlana V.; Mironov, Alexey Yu.; Baklanov, Mikhail R.; ...

    2017-05-11

    A reentrant temperature dependence of the normal state resistance often referred to as the N-shaped temperature dependence, is omnipresent in disordered superconductors – ranging from high-temperature cuprates to ultrathin superconducting films – that experience superconductor-to-insulator transition. Yet, despite the ubiquity of this phenomenon its origin still remains a subject of debate. Here we investigate strongly disordered superconducting TiN films and demonstrate universality of the reentrant behavior. We offer a quantitative description of the N-shaped resistance curve. We show that upon cooling down the resistance first decreases linearly with temperature and then passes through the minimum that marks the 3D-2D crossovermore » in the system. In the 2D temperature range the resistance first grows with decreasing temperature due to quantum contributions and eventually drops to zero as the system falls into a superconducting state. As a result, our findings demonstrate the prime importance of disorder in dimensional crossover effects.« less

  4. High Fat Diet Produces Brain Insulin Resistance, Synaptodendritic Abnormalities and Altered Behavior in Mice

    PubMed Central

    Arnold, Steven E.; Lucki, Irwin; Brookshire, Bethany R.; Carlson, Gregory C.; Browne, Carolyn A.; Kazi, Hala; Bang, Sookhee; Choi, Bo-Ran; Chen, Yong; McMullen, Mary F.; Kim, Sangwon F.

    2014-01-01

    Insulin resistance and other features of the metabolic syndrome are increasingly recognized for their effects on cognitive health. To ascertain mechanisms by which this occurs, we fed mice a very high fat diet (60% kcal by fat) for 17 days or a moderate high fat diet (HFD, 45% kcal by fat) for 8 weeks and examined changes in brain insulin signaling responses, hippocampal synaptodendritic protein expression, and spatial working memory. Compared to normal control diet mice, cerebral cortex tissues of HFD mice were insulin-resistant as evidenced by failed activation of Akt, S6 and GSK3β with ex-vivo insulin stimulation. Importantly, we found that expression of brain IPMK, which is necessary for mTOR/Akt signaling, remained decreased in HFD mice upon activation of AMPK. HFD mouse hippocampus exhibited increased expression of serine-phosphorylated insulin receptor substrate 1 (IRS1-pS616), a marker of insulin resistance, as well as decreased expression of PSD-95, a scaffolding protein enriched in post-synaptic densities, and synaptopodin, an actin-associated protein enriched in spine apparatuses. Spatial working memory was impaired as assessed by decreased spontaneous alternation in a T-maze. These findings indicate that HFD is associated with telencephalic insulin resistance and deleterious effects on synaptic integrity and cognitive behaviors. PMID:24686304

  5. Long-term electrical resistivity monitoring of recharge-induced contaminant plume behavior

    NASA Astrophysics Data System (ADS)

    Gasperikova, Erika; Hubbard, Susan S.; Watson, David B.; Baker, Gregory S.; Peterson, John E.; Kowalsky, Michael B.; Smith, Meagan; Brooks, Scott

    2012-11-01

    Geophysical measurements, and electrical resistivity tomography (ERT) data in particular, are sensitive to properties that are related (directly or indirectly) to hydrological processes. The challenge is in extracting information from geophysical data at a relevant scale that can be used to gain insight about subsurface behavior and to parameterize or validate flow and transport models. Here, we consider the use of ERT data for examining the impact of recharge on subsurface contamination at the S-3 ponds of the Oak Ridge Integrated Field Research Challenge (IFRC) site in Tennessee. A large dataset of time-lapse cross-well and surface ERT data, collected at the site over a period of 12 months, is used to study time variations in resistivity due to changes in total dissolved solids (primarily nitrate). The electrical resistivity distributions recovered from cross-well and surface ERT data agrees well, and both of these datasets can be used to interpret spatiotemporal variations in subsurface nitrate concentrations due to rainfall, although the sensitivity of the electrical resistivity response to dilution varies with nitrate concentration. Using the time-lapse surface ERT data interpreted in terms of nitrate concentrations, we find that the subsurface nitrate concentration at this site varies as a function of spatial position, episodic heavy rainstorms (versus seasonal and annual fluctuations), and antecedent rainfall history. These results suggest that the surface ERT monitoring approach is potentially useful for examining subsurface plume responses to recharge over field-relevant scales.

  6. Long-term electrical resistivity monitoring of recharge-induced contaminant plume behavior.

    PubMed

    Gasperikova, Erika; Hubbard, Susan S; Watson, David B; Baker, Gregory S; Peterson, John E; Kowalsky, Michael B; Smith, Meagan; Brooks, Scott

    2012-11-01

    Geophysical measurements, and electrical resistivity tomography (ERT) data in particular, are sensitive to properties that are related (directly or indirectly) to hydrological processes. The challenge is in extracting information from geophysical data at a relevant scale that can be used to gain insight about subsurface behavior and to parameterize or validate flow and transport models. Here, we consider the use of ERT data for examining the impact of recharge on subsurface contamination at the S-3 ponds of the Oak Ridge Integrated Field Research Challenge (IFRC) site in Tennessee. A large dataset of time-lapse cross-well and surface ERT data, collected at the site over a period of 12 months, is used to study time variations in resistivity due to changes in total dissolved solids (primarily nitrate). The electrical resistivity distributions recovered from cross-well and surface ERT data agrees well, and both of these datasets can be used to interpret spatiotemporal variations in subsurface nitrate concentrations due to rainfall, although the sensitivity of the electrical resistivity response to dilution varies with nitrate concentration. Using the time-lapse surface ERT data interpreted in terms of nitrate concentrations, we find that the subsurface nitrate concentration at this site varies as a function of spatial position, episodic heavy rainstorms (versus seasonal and annual fluctuations), and antecedent rainfall history. These results suggest that the surface ERT monitoring approach is potentially useful for examining subsurface plume responses to recharge over field-relevant scales. Published by Elsevier B.V.

  7. Resistive switching behavior in single crystal SrTiO3 annealed by laser

    NASA Astrophysics Data System (ADS)

    Pan, Xinqiang; Shuai, Yao; Wu, Chuangui; Luo, Wenbo; Sun, Xiangyu; Yuan, Ye; Zhou, Shengqiang; Ou, Xin; Zhang, Wanli

    2016-12-01

    Single crystal SrTiO3 (STO) wafers were annealed by XeCl laser (λ = 308 nm) with different fluences of 0.4 J/cm2, 0.6 J/cm2 and 0.8 J/cm2, respectively. Ti/Pt electrodes were sputtered on the surface of STO wafer to form co-planar capacitor-like structures of Pt/Ti/STO/Ti/Pt. Current-Voltage measurements show that the leakage current is enhanced by increasing laser fluence. Resistive switching behavior is only observed in the sample annealed by laser with relatively high fluence after an electro-forming process. The X-ray photoelectron spectroscopy measurements indicate that the amount of oxygen vacancies increases with the increase of laser fluence. This work indicates resistive switching appears when enough oxygen vacancies are generated by the laser, which form conductive filaments under an external electric field.

  8. [Antibiotic intake and resistance development - Knowledge, experience and behavior among the German general population].

    PubMed

    Schneider, Sandra; Salm, Florian; Schröder, Christin; Ludwig, Norman; Hanke, Regina; Gastmeier, Petra

    2016-09-01

    The network project RAI (Rational Use of Antibiotics via Information and Communication) is aimed at developing tailored information and communication tools on the subject of antibiotic (AB) resistance for various stakeholder groups. During the preparation phase, a survey was performed addressing the German general population. To gain insights into the knowledge, attitudes, and behavior of nonprescribers concerning AB and multidrug-resistant organisms (MDRO). Using computer-assisted, telephone-based interviews a random sample of 1,004 persons aged 14 years and older was surveyed. Descriptive reporting of data and multivariate analysis were performed, including sociodemographic variables. Only 24 % of participants knew that bacteria (but not viruses or humans) could develop AB resistance. However, this knowledge did not influence the outcome of other questions. Regardless of knowledge, 71 % thought that the subject was important, but 58 % did not believe in the influence of their own behavior on MDRO development. When visiting a physician, patients were given an antibiotic three times as often as information on AB resistance. 17 % did not take the AB as prescribed and 20 % of all participants stated that they personally knew at least one person with MDRO problems. This personal involvement had a significant effect on the rating of self-influence, on the importance of the subject, on the interaction between patient and physician (more information, less AB), and on AB intake compliance (less frequent). We found considerable knowledge gaps, but this had no impact on the assessment of the subject. A starting point for an intervention could be patient-physician communication. This seems more effective and safer than a public campaign.

  9. Does Drought Increase the Risk of Insects Developing Behavioral Resistance to Systemic Insecticides?

    PubMed Central

    Fowles, Trevor; Bick, Emily; Nansen, Christian

    2016-01-01

    Increases in severity and frequency of drought periods, average global temperatures, and more erratic fluctuations in rainfall patterns due to climate change are predicted to have a dramatic impact on agricultural production systems. Insect pest populations in agricultural and horticultural systems are also expected to be impacted, both in terms of their spatial and temporal distributions and in their status as pest species. In this opinion-based article, we discuss how indirect effects of drought may adversely affect the performance of systemic insecticides and also lead to increased risk of insect pests developing behavioral insecticide resistance. We hypothesize that more pronounced drought will decrease uptake and increase the magnitude of nonuniform translocation of systemic insecticides within treated crop plants, and that may have two concurrent consequences: 1) reduced pesticide performance, and 2) increased likelihood of insect pests evolving behavioral insecticide resistance. Under this scenario, pests that can sense and avoid acquisition of lethal dosages of systemic insecticides within crop plants will have a selective advantage. This may lead to selection for insect behavioral avoidance, so that insects predominantly feed and oviposit on portions of crop plants with low concentration of systemic insecticide. Limited research has been published on the effect of environmental variables, including drought, on pesticide performance, but we present and discuss studies that support the hypothesis described above. In addition, we wish to highlight the importance of studying the many ways environmental factors can affect, directly and indirectly, both the performance of insecticides and the risk of target insect pests developing resistance. PMID:27551149

  10. Behavioral effects on rats of high strength magnetic fields generated by a resistive electromagnet.

    PubMed

    Houpt, Thomas A; Pittman, David W; Riccardi, Christina; Cassell, Jennifer A; Lockwood, Denesa R; Barranco, Jan M; Kwon, Bumsup; Smith, James C

    2005-10-15

    It has been reported previously that exposure to static high magnetic fields of 7 T or above in superconducting magnets has behavioral effects on rats. In particular, magnetic field exposure acutely but transiently suppressed rearing and induced walking in tight circles; the direction of circular locomotion was dependent on the rats' orientation within the magnet. Furthermore, when magnet exposure was paired with consumption of a palatable, novel solution, rats acquired a persistent taste aversion. In order to confirm these results under more controlled conditions, we exposed rats to static magnetic fields of 4 to 19.4 T in a 189 mm bore, 20 T resistive magnet. By using a resistive magnet, field strengths could be arbitrary varied from -19.4 to 19.4 T within the same bore. Rearing was suppressed after exposure to 4 T and above; circling was observed after 7 T and above. Conditioned taste aversion was acquired after 14 T and above. The effects of the magnetic fields were dependent on orientation. Exposure to +14 T induced counter-clockwise circling, while exposure to -14 T induced clockwise circling. Exposure with the rostral-caudal axis of the rat perpendicular to the magnetic field produced an attenuated behavioral response compared to exposure with the rostral-caudal axis parallel to the field. These results in a single resistive magnet confirm and extend our earlier findings using multiple superconducting magnets. They demonstrate that the behavioral effects of exposure within large magnets are dependent on the magnetic field, and not on non-magnetic properties of the machinery. Finally, the effects of exposure to 4 T are clinically relevant, as 4 T magnetic fields are commonly used in functional MRI assays.

  11. Does Drought Increase the Risk of Insects Developing Behavioral Resistance to Systemic Insecticides?

    PubMed

    Khodaverdi, Haleh; Fowles, Trevor; Bick, Emily; Nansen, Christian

    2016-10-01

    Increases in severity and frequency of drought periods, average global temperatures, and more erratic fluctuations in rainfall patterns due to climate change are predicted to have a dramatic impact on agricultural production systems. Insect pest populations in agricultural and horticultural systems are also expected to be impacted, both in terms of their spatial and temporal distributions and in their status as pest species. In this opinion-based article, we discuss how indirect effects of drought may adversely affect the performance of systemic insecticides and also lead to increased risk of insect pests developing behavioral insecticide resistance. We hypothesize that more pronounced drought will decrease uptake and increase the magnitude of nonuniform translocation of systemic insecticides within treated crop plants, and that may have two concurrent consequences: 1) reduced pesticide performance, and 2) increased likelihood of insect pests evolving behavioral insecticide resistance. Under this scenario, pests that can sense and avoid acquisition of lethal dosages of systemic insecticides within crop plants will have a selective advantage. This may lead to selection for insect behavioral avoidance, so that insects predominantly feed and oviposit on portions of crop plants with low concentration of systemic insecticide. Limited research has been published on the effect of environmental variables, including drought, on pesticide performance, but we present and discuss studies that support the hypothesis described above. In addition, we wish to highlight the importance of studying the many ways environmental factors can affect, directly and indirectly, both the performance of insecticides and the risk of target insect pests developing resistance. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America.

  12. Nonlinear current-voltage behavior of the isolated resistive switching filamentary channels in CuC nanolayer

    SciTech Connect

    Kim, Doo-In; Yoon, Jaesik; Kim, Young Moon; Kwon, Se Hun; Kim, Kwang Ho; Park, Ju-Bong; Hwang, Hyunsang

    2011-04-11

    Copper-doped amorphous carbon film was prepared by radio frequency reactive magnetron sputtering and their resistive switching behaviors were studied under a conductive atomic force microscope (cAFM). The repetitive scanning over the same area using cAFM with various bias voltages revealed that most of the isolated conductive paths were involved in resistive switching with asymmetric nonlinear I-V characteristics. The observed I-V behavior of nanoscale filamentary channels indicates that electron transfer mechanism of resistive switching filamentary channel in Pt/CuC/Pt is a tunneling between Cu filamentary channel and electrode through the solid electrolyte rather than conduction through fully connected Cu filamentary channel.

  13. Negative differential resistance behavior in phosphorus-doped armchair graphene nanoribbon junctions

    SciTech Connect

    Zhou, Yuhong; Zhang, Daoli Zhang, Jianbing; Miao, Xiangshui; Ye, Cong

    2014-02-21

    In this present work, we investigate the electronic transport properties of phosphorus-doped armchair graphene nanoribbon (AGNR) junctions by employing nonequilibrium Green's functions in combination with the density-function theory. Two phosphorus (P) atoms are considered to substitute the central carbon atom with the different width of AGNRs. The results indicate that the electronic transport behaviors are strongly dependent on the width of the P-doped graphene nanoribbons. The current-voltage characteristics of the doped AGNR junctions reveal an interesting negative differential resistance (NDR) and exhibit three distinct family (3 n, 3 n + 1, 3 n + 2) behaviors. These results display that P doping is a very good way to achieve NDR of the graphene nanoribbon devices.

  14. Negative differential resistance behavior in phosphorus-doped armchair graphene nanoribbon junctions

    NASA Astrophysics Data System (ADS)

    Zhou, Yuhong; Zhang, Daoli; Zhang, Jianbing; Ye, Cong; Miao, Xiangshui

    2014-02-01

    In this present work, we investigate the electronic transport properties of phosphorus-doped armchair graphene nanoribbon (AGNR) junctions by employing nonequilibrium Green's functions in combination with the density-function theory. Two phosphorus (P) atoms are considered to substitute the central carbon atom with the different width of AGNRs. The results indicate that the electronic transport behaviors are strongly dependent on the width of the P-doped graphene nanoribbons. The current-voltage characteristics of the doped AGNR junctions reveal an interesting negative differential resistance (NDR) and exhibit three distinct family (3 n, 3 n + 1, 3 n + 2) behaviors. These results display that P doping is a very good way to achieve NDR of the graphene nanoribbon devices.

  15. Effects of low-molecular weight resist components on dissolution behavior of chemically amplified resists for extreme ultraviolet lithography studied by quartz crystal microbalance

    NASA Astrophysics Data System (ADS)

    Mitsuyasu, Masaki; Yamamoto, Hiroki; Kozawa, Takahiro

    2015-03-01

    It is challenging to implement extreme ultraviolet (EUV) lithography for mass production because the demands for the EUV resist materials are very strict. Under such circumstances, it is important in EUV resist design to clarify the dissolution behavior of the resist film into alkaline developer. In particular, the dissolution in exposed area of resist films is one of the most critical processes. However, the details in dissolution process of EUV resist have not been investigated thus far. In this study, the dissolution of poly(4-hydroxystyrene) (PHS) polymer and PHS partially-protected with t-butoxycarbonyl group (t-BOC-PHS) with and without additives such as acid generator and amines was studied by using the quartz crystal microbalance (QCM) method. The dissolution behavior of thin films was investigated by varying the exposure dose and the acid generator concentration from the standpoint of a systematic understanding of the effects of each resist component on dissolution kinetics. The dissolution speed became slower with increase of TPS-tf concentration in PHS and t-BOC-PHS. It is important for the EUV resist design to take into account the concentration of undecomposed PAG.

  16. Dietary resistant starch improves selected brain and behavioral functions in adult and aged rodents.

    PubMed

    Zhou, June; Keenan, Michael J; Fernandez-Kim, Sun Ok; Pistell, Paul J; Ingram, Donald K; Li, Bing; Raggio, Anne M; Shen, Li; Zhang, Hanjie; McCutcheon, Kathleen L; Tulley, Richard T; Blackman, Marc R; Keller, Jeffrey N; Martin, Roy J

    2013-11-01

    Resistant starch (RS) is a dietary fiber that exerts multiple beneficial effects. The current study explored the effects of dietary RS on selected brain and behavioral functions in adult and aged rodents. Because glucokinase (GK) expression in hypothalamic arcuate nucleus and area postrema of the brainstem is important for brain glucose sensing, GK mRNA was measured by brain nuclei microdissection and PCR. Adult RS-fed rats had a higher GK mRNA than controls in both brain nuclei, an indicator of improved brain glucose sensing. Next, we tested whether dietary RS improve selected behaviors in aged mice. RS-fed aged mice exhibited (i) an increased eating responses to fasting, a behavioral indicator of improvement in aged brain glucose sensing; (ii) a longer latency to fall from an accelerating rotarod, a behavioral indicator of improved motor coordination; and (iii) a higher serum active glucagon-like peptide-1 (GLP-1). Then, GLP-1 receptor null (GLP-1RKO) mice were used to test the role of GLP-1 in brain glucose sensing, and they exhibited impaired eating responses to fasting. We conclude that in rodents (i) dietary RS improves two important indicators of brain function: glucose sensing and motor coordination, and (ii) GLP-1 is important in the optimal feeding response to a fast.

  17. The Model of Motivational Dynamics in Sport: Resistance to Peer Influence, Behavioral Engagement and Disaffection, Dispositional Coping, and Resilience.

    PubMed

    Nicholls, Adam R; Morley, David; Perry, John L

    2015-01-01

    The Model of Motivational Dynamics (MMD; Skinner and Pitzer, 2012) infers that peers influence behavioral engagement levels, which in turn is linked to coping and resilience. Scholars, however, are yet to test the MMD among an athletic population. The purpose of this paper was to assess an a priori model that included key constructs from the MMD, such as resistance to peer influence, behavioral engagement and disaffection, coping, and resilience among athletes. Three hundred and fifty-one athletes (male n = 173, female n = 178; M age = 16.15 years) completed a questionnaire that measured each construct. Our results provide support for the model. In particular, there were positive paths between resistance to peer influence and behavioral engagement, behavioral engagement and task-oriented coping, and task-oriented coping with resilience. There was also a positive path between resilience and resistance to peer influence, but a negative path from resistance to peer influence to behavioral disaffection. Due to the reported benefits of enhancing resistance to peer influence and behavioral engagement, researchers could devise sport specific interventions to maximize athletes' scores in these constructs.

  18. The Model of Motivational Dynamics in Sport: Resistance to Peer Influence, Behavioral Engagement and Disaffection, Dispositional Coping, and Resilience

    PubMed Central

    Nicholls, Adam R.; Morley, David; Perry, John L.

    2016-01-01

    The Model of Motivational Dynamics (MMD; Skinner and Pitzer, 2012) infers that peers influence behavioral engagement levels, which in turn is linked to coping and resilience. Scholars, however, are yet to test the MMD among an athletic population. The purpose of this paper was to assess an a priori model that included key constructs from the MMD, such as resistance to peer influence, behavioral engagement and disaffection, coping, and resilience among athletes. Three hundred and fifty-one athletes (male n = 173, female n = 178; Mage = 16.15 years) completed a questionnaire that measured each construct. Our results provide support for the model. In particular, there were positive paths between resistance to peer influence and behavioral engagement, behavioral engagement and task-oriented coping, and task-oriented coping with resilience. There was also a positive path between resilience and resistance to peer influence, but a negative path from resistance to peer influence to behavioral disaffection. Due to the reported benefits of enhancing resistance to peer influence and behavioral engagement, researchers could devise sport specific interventions to maximize athletes’ scores in these constructs. PMID:26779107

  19. Bipolar resistive switching behavior of an amorphous Ge₂Sb₂Te₅ thin films with a Te layer.

    PubMed

    Yoo, Sijung; Eom, Taeyong; Gwon, Taehong; Hwang, Cheol Seong

    2015-04-14

    The mechanism of bipolar resistive switching (BRS) of amorphous Ge2Sb2Te5 (GST) thin films sandwiched between inert electrodes (Ti and Pt) was examined. Typical bipolar resistive switching behavior with a high resistance ratio (∼10(3)) and reliable switching characteristics was achieved. High-resolution transmission electron microscopy revealed the presence of a conductive Te-filament bridging between the top and bottom electrodes through an amorphous GST matrix. The conduction mechanism analysis showed that the low-resistance state was semiconducting and dominated by band transport, whereas Poole-Frenkel conduction governed the carrier transport in the high-resistance state. Thus, the BRS behavior can be attributed to the formation and rupture of the semiconducting conductive Te bridge through the migration of the Te ions in the amorphous GST matrix under a high electric field. The Te ions are provided by the thin (∼5 nm) Te-rich layer formed at the bottom electrode interface.

  20. Reentrant behavior in the superconducting phase-dependent resistance of a disordered two-dimensional electron gas

    SciTech Connect

    den Hartog, S.G.; van Wees, B.J.; Klapwijk, T.M.; Nazarov, Y.V.; Borghs, G.

    1997-12-01

    We have investigated the bias-voltage dependence of the phase-dependent differential resistance of a disordered T-shaped two-dimensional electron gas coupled to two superconducting terminals. The resistance oscillations first increase upon lowering the energy. For bias voltages below the Thouless energy, the resistance oscillations are suppressed and disappear almost completely at zero bias voltage. We find a qualitative agreement with the calculated reentrant behavior of the resistance and discuss quantitative deviations. {copyright} {ital 1997} {ital The American Physical Society}

  1. Mechanical flexible and electric fatigue resistant behavior of relaxor ferroelectric terpolymer

    NASA Astrophysics Data System (ADS)

    Fang, Fei; Yang, Wei; Yang, Wen

    2009-08-01

    Uniaxial tension and polarization evolution under cyclic electric field are investigated for poly(vinylidene fluoride-trifluorethylene-chlorofluoroethylene) terpolymer films prepared by different annealing conditions. The stress-strain behavior of the terpolymer film exhibits that of polymeric elastomers, with its fracture strain reaching 680%. Structure analysis demonstrates that the polymer chains undergo reorientation, and conformational change from nonpolar to polar phase takes place during uniaxial tension. Under cyclic electric field, the terpolymer film exhibits a narrow polarization loop typical of a ferroelectric relaxor. Conformational change from nonpolar to polar phase also occurs upon the electric field, and it reverses to the nonpolar phase when the field is removed. As the cycle number accumulates, the terpolymer film demonstrates excellent resistance to electric fatigue. Compared to the film annealed at 115 °C, the terpolymer film annealed at 100 °C has a larger volume fraction of crystallite/amorphous interfaces and shows better mechanical flexibility as well as electric fatigue resistance. The mechanical flexible and electric fatigue resistant terpolymer films hold promises for many applications, ranging from embedded sensors and actuators to flexible memory devices.

  2. Treatment-resistant depression in adolescents: is the addition of cognitive behavioral therapy of benefit?

    PubMed Central

    Hetrick, Sarah E; Cox, Georgina R; Merry, Sally N

    2011-01-01

    Background Many young people with major depression fail first-line treatments. Treatment-resistant depression has various definitions in the literature but typically assumes nonresponse to medication. In young people, cognitive behavioral therapy (CBT) is the recommended first-line intervention, thus the definition of treatment resistance should be expanded. Therefore, our aim was to synthesize the existing evidence of any interventions for treatment-resistant depression, broadly defined, in children and adolescents and to investigate the effectiveness of CBT in this context. Methods We used Cochrane Collaboration methodology, with electronic searches of Medline, PsycINFO, Embase, and the Cochrane Depression Anxiety and Neurosis Group trials registers. Only randomized controlled trials were included, and were assessed for risk of bias. Meta- analysis was undertaken where possible and appropriate. Results Of 953 articles retrieved, four trials were eligible for inclusion. For one study, only the trial registration document was available, because the study was never completed. All other studies were well conducted with a low risk of bias, although one study had a high dropout rate. Two studies assessed the effect of adding CBT to medication. While an assertive trial of antidepressants does appear to lead to benefit, when compared with placebo, there was no significant advantage, in either study, or in a meta-analysis of data from these trials, that clearly demonstrated an additional benefit of CBT. The third trial showed little advantage of a tricyclic antidepressant over placebo in the context of an inpatient admission. Conclusion Few randomized controlled trials have investigated interventions for treatment-resistant depression in young people, and results from these show modest benefit from antidepressants with no additional benefit over medication from CBT. Overall, there is a lack of evidence about effective interventions to treat young people who have failed to

  3. Resistive switching behavior in Lu2O3 thin film for advanced flexible memory applications

    PubMed Central

    2014-01-01

    In this article, the resistive switching (RS) behaviors in Lu2O3 thin film for advanced flexible nonvolatile memory applications are investigated. Amorphous Lu2O3 thin films with a thickness of 20 nm were deposited at room temperature by radio-frequency magnetron sputtering on flexible polyethylene terephthalate substrate. The structural and morphological changes of the Lu2O3 thin film were characterized by x-ray diffraction, atomic force microscopy, and x-ray photoelectron spectroscopy analyses. The Ru/Lu2O3/ITO flexible memory device shows promising RS behavior with low-voltage operation and small distribution of switching parameters. The dominant switching current conduction mechanism in the Lu2O3 thin film was determined as bulk-controlled space-charge-limited-current with activation energy of traps of 0.33 eV. The oxygen vacancies assisted filament conduction model was described for RS behavior in Lu2O3 thin film. The memory reliability characteristics of switching endurance, data retention, good flexibility, and mechanical endurance show promising applications in future advanced memory. PMID:24387704

  4. Differential reinforcement of alternative behavior increases resistance to extinction: clinical demonstration, animal modeling, and clinical test of one solution.

    PubMed

    Mace, F Charles; McComas, Jennifer J; Mauro, Benjamin C; Progar, Patrick R; Taylor, Bridget; Ervin, Ruth; Zangrillo, Amanda N

    2010-05-01

    Basic research with pigeons on behavioral momentum suggests that differential reinforcement of alternative behavior (DRA) can increase the resistance of target behavior to change. This finding suggests that clinical applications of DRA may inadvertently increase the persistence of target behavior even as it decreases its frequency. We conducted three coordinated experiments to test whether DRA has persistence-strengthening effects on clinically significant target behavior and then tested the effectiveness of a possible solution to this problem in both a nonhuman and clinical study. Experiment 1 compared resistance to extinction following baseline rates of reinforcement versus higher DRA rates of reinforcement in a clinical study. Resistance to extinction was substantially greater following DRA. Experiment 2 tested a rat model of a possible solution to this problem. Training an alternative response in a context without reinforcement of the target response circumvented the persistence-strengthening effects of DRA. Experiment 3 translated the rat model into a novel clinical application of DRA. Training an alternative response with DRA in a separate context resulted in lower resistance to extinction than employing DRA in the context correlated with reinforcement of target behavior. The value of coordinated bidirectional translational research is discussed.

  5. Differential Reinforcement of Alternative Behavior Increases Resistance to Extinction: Clinical Demonstration, Animal Modeling, and Clinical Test of One Solution

    PubMed Central

    Mace, F. Charles; McComas, Jennifer J; Mauro, Benjamin C; Progar, Patrick R; Taylor, Bridget; Ervin, Ruth; Zangrillo, Amanda N

    2010-01-01

    Basic research with pigeons on behavioral momentum suggests that differential reinforcement of alternative behavior (DRA) can increase the resistance of target behavior to change. This finding suggests that clinical applications of DRA may inadvertently increase the persistence of target behavior even as it decreases its frequency. We conducted three coordinated experiments to test whether DRA has persistence-strengthening effects on clinically significant target behavior and then tested the effectiveness of a possible solution to this problem in both a nonhuman and clinical study. Experiment 1 compared resistance to extinction following baseline rates of reinforcement versus higher DRA rates of reinforcement in a clinical study. Resistance to extinction was substantially greater following DRA. Experiment 2 tested a rat model of a possible solution to this problem. Training an alternative response in a context without reinforcement of the target response circumvented the persistence-strengthening effects of DRA. Experiment 3 translated the rat model into a novel clinical application of DRA. Training an alternative response with DRA in a separate context resulted in lower resistance to extinction than employing DRA in the context correlated with reinforcement of target behavior. The value of coordinated bidirectional translational research is discussed. PMID:21119850

  6. Resistance Memory Switching behavior in MnOx, FeOx, CoOx, and NiOx thin films.

    NASA Astrophysics Data System (ADS)

    Jung, Ranju; Seo, Sunae; Kim, Doungchirl; Lee, Chang-Won; Yoo, Inkyung; Kim, Sanghoon; Park, Baeho

    2007-03-01

    We have fabricated the ReRAM(Resistance change Random Access Memory) with some ferromagnetic transition metal(Co, Fe, Mn) oxides materials. Antiferromagnetic NiOx film is well known to show non-volatile resistance switching property. Here, we have studied the relationship between magnetic property and resistance switching properties. We have deposited the MnOx, FeOx, CoOx, and NiOx thin films on Pt/Ti/SiO2/Si (111) by using Pulsed Laser Deposition (PLD), and then analyzed the structural properties of these oxides thin films by using X-Ray diffraction (XRD) and Scanning Electron Microscope (SEM), surface properties using Atomic Force Microscope (AFM), and electrical properties using probe station. Every thin film shows poly-crystalline behaviors and reproducible resistance switching behaviors. We have performed the temperature-dependent electrical property measurement across the Neel temperature.

  7. Resisting pressure from peers to engage in sexual behavior: What communication strategies do early adolescent Latino Girls use?

    PubMed

    Norris, Anne E; Pettigrew, Jonathan; Miller-Day, Michelle; Hecht, Michael L; Hutchison, Janet; Campoe, Kristi

    2015-05-01

    A content analysis of early adolescent (M=12.02 years) Latino girls' (n=44) responses to open-ended questions imbedded in an electronic survey was conducted to explore strategies girls may use to resist peer pressure with respect to sexual behavior. Analysis yielded 341 codable response units, 74% of which were consistent with the REAL typology (i.e., refuse, explain, avoid, and leave) previously identified in adolescent substance use research. However, strategies reflecting a lack of resistance (11%) and inconsistency with communication competence (e.g., aggression, involving authorities) were also noted (15%). Frequency of particular strategies varied according to offer type, suggesting a variety of strategies may be needed to resist the peer pressure that puts early adolescent girls at risk for engaging in sexual behavior. Findings argue for universality of the REAL typology, building communication competence skills for conflict resolution in dating situations, and including peer resistance strategies in adolescent pregnancy prevention programs.

  8. Quetiapine add-on therapy improves the depressive behaviors and hippocampal neurogenesis in fluoxetine treatment resistant depressive rats.

    PubMed

    Wang, Ying; Chang, Ting; Chen, Yun-Chun; Zhang, Rui-Guo; Wang, Hua-Ning; Wu, Wen-Jun; Peng, Zheng-Wu; Tan, Qing-Rong

    2013-09-15

    Quetiapine, an atypical antipsychotic, may have efficacy as augmentation therapy in treatment resistant depression (TRD), but evidence is limited and the underlying mechanism remains poorly understood. Therefore, this study was aimed to investigate whether and how quetiapine can be served as an augmentation agent in fluoxetine treatment resistant depressive rats induced by chronic unpredictable mild stress (CUMS). In this study, the effects of CUMS regimen and antidepressant treatment were assessed by behavioral tests and hippocampal neurogenesis. Approximately 20-30% of depressive rats respond poorly to fluoxetine treatment. In their hippocampus, a significant decrease of neurogenesis was also observed. However, quetiapine add-on therapy significantly improved the depressive behaviors and increased the number of the newborn neurons in the hippocampus of fluoxetine treatment resistant depressive rats. Thus, our results suggest that quetiapine may be used as an augmentation agent in the treatment resistant depression partly mediated by increasing the number of newborn neurons in the hippocampus.

  9. Resisting pressure from peers to engage in sexual behavior: What communication strategies do early adolescent Latino Girls use?

    PubMed Central

    Norris, Anne E.; Pettigrew, Jonathan; Miller-Day, Michelle; Hecht, Michael L.; Hutchison, Janet; Campoe, Kristi

    2015-01-01

    A content analysis of early adolescent (M=12.02 years) Latino girls’ (n=44) responses to open-ended questions imbedded in an electronic survey was conducted to explore strategies girls may use to resist peer pressure with respect to sexual behavior. Analysis yielded 341 codable response units, 74% of which were consistent with the REAL typology (i.e., refuse, explain, avoid, and leave) previously identified in adolescent substance use research. However, strategies reflecting a lack of resistance (11%) and inconsistency with communication competence (e.g., aggression, involving authorities) were also noted (15%). Frequency of particular strategies varied according to offer type, suggesting a variety of strategies may be needed to resist the peer pressure that puts early adolescent girls at risk for engaging in sexual behavior. Findings argue for universality of the REAL typology, building communication competence skills for conflict resolution in dating situations, and including peer resistance strategies in adolescent pregnancy prevention programs. PMID:26146434

  10. [Correlation of resistance to peer pressure and risky decision-making with adolescent health risk behaviors].

    PubMed

    An, Jing; Sun, Ying; Wang, Xi; Zu, Ping; Mai, Jin-cheng; Liang, Jian-ping; Xu, Zhi-yong; Man, Xue-jun; Mao, Yan; Tao, Fang-biao

    2013-03-01

    To explore possible interrelationships among resistance to peer pressure, risky decision-making and health risk behaviors among young adolescents. Based on the cluster sampling method, the participants who were recruited from 5 junior middle schools in Guangzhou and 3 junior middle schools in Shenyang city on October, 2010, were administered to complete the questionnaire concerned with their experiences with drinking and smoking during the past 30 days preceding the survey, and the hours using computer daily both in weekdays and in weekend. The level of resistance to peer influence and risky decision-making were assessed by Resistance to peer influence scale (RPIS) and Youth decision-making questionnaire (YDMQ). Logistic regression was used to explore possible interrelationships among resistance to peer influence, risky decision-making and health risk behaviors among young adolescents. A total of 1985 questionnaires were valid, including 1001(50.4%) boys and 984 (49.6%) girls. About 27.1% (537/1985) junior middle school students reported having health risk behaviors, boys' (30.7%, 307/1001) was higher than girls' (23.4%, 230/984) with significant gender difference (P < 0.05). The prevalence of smoking, drinking during the past 30 days before the survey and using computer over 3 hours daily in weekdays and in weekend were 5.1% (102/1985), 14.3% (284/1985), 3.5% (70/1985) and 13.7% (272/1985), respectively. The rate of drinking, using computer over 3 hours daily in weekdays and in weekend were higher in males (16.4% (164/1001), 4.5% (45/1001), 16.2% (162/1001)) than those in females (12.2% (120/984), 2.5% (25/984), 11.2% (110/984)) (P < 0.05). The scores of RPIS and YDMQ of the two cities adolescents were 2.82 ± 0.39 and 1.68 ± 0.62. The students reported smoking, drinking during the past 30 days before the survey and using computer over 3 hours daily in weekend gained lower RPIS scores (2.43 ± 0.40, 2.61 ± 0.41, 2.77 ± 0.40) than their counterparts who didn

  11. Behavioral and Socioeconomic Risk Factors Associated with Probable Resistance to Ceftriaxone and Resistance to Penicillin and Tetracycline in Neisseria gonorrhoeae in Shanghai

    PubMed Central

    Trecker, Molly A.; Waldner, Cheryl; Jolly, Ann; Liao, Mingmin; Gu, Weiming; Dillon, Jo-Anne R.

    2014-01-01

    Globally, incidence of Neisseria gonorrhoeae infection is once again the highest of the bacterial sexually transmitted infections. The bacterium can produce serious complications in those infected, and emerging resistance to third generation cephalosporins could usher in an era of potentially untreatable gonorrhea. This research aimed to identify risk factors for antibiotic resistant gonorrhea infection among clients at a Shanghai sexually transmitted infection clinic over two time periods, 2004–2005 and 2008–2011. Demographic and risk factor behavior data, and biological samples for antimicrobial resistance analysis, were collected. Statistical models were built to identify risk factors associated with probable resistance to ceftriaxone and resistance to penicillin and tetracycline. High levels of ciprofloxacin resistance (98%) in our sample precluded examining its risk factors; all isolates were susceptible to spectinomycin. Overall (P<0.001), chromosomal (P<0.001), and plasmid-mediated (P = 0.01) penicillin resistance decreased from the first to second period of the study. For tetracycline, chromosomal resistance decreased (P = 0.01) and plasmid-mediated resistance increased (P<0.001) between the first and second periods of study. In multi-level multivariable regression models, male gender (P = 0.03) and older age (P = 0.01) were associated with increased minimum inhibitory concentrations to ceftriaxone. Male gender (P = 0.03) and alcohol use (P = 0.02) were associated with increased odds of overall tetracycline resistance. Male gender was associated with increased odds of chromosomally-mediated tetracycline resistance (P = 0.04), and alcohol use was associated with increased odds of plasmid-mediated tetracycline resistance (P = 0.02). Additionally, individuals in middle-salary categories were found to have lower odds of plasmid-mediated resistance to tetracycline compared with those in the lowest salary category (P≤0

  12. Structural, electronic, mechanical, and transport properties of phosphorene nanoribbons: Negative differential resistance behavior

    NASA Astrophysics Data System (ADS)

    Maity, Ajanta; Singh, Akansha; Sen, Prasenjit; Kibey, Aniruddha; Kshirsagar, Anjali; Kanhere, Dilip G.

    2016-08-01

    Structural, electronic, mechanical, and transport properties of two different types of phosphorene nanoribbons are calculated within the density functional theory and nonequilibrium Green's function formalisms. Armchair nanoribbons turn out to be semiconductors at all widths considered. Zigzag nanoribbons are metallic in their layer-terminated structure, but undergo Peierls-like transition at the edges. Armchair nanoribbons have smaller Young's modulus compared to a monolayer, while zigzag nanoribbons have larger Young's modulus. Edge reconstruction further increases the Young's modulus of zigzag nanoribbons. A two-terminal device made of zigzag nanoribbons show negative differential resistance behavior that is robust with respect to edge reconstruction. We have also calculated the I -V characteristics for two nonzero gate voltages. The results show that the zigzag nanoribbons display strong p -type character.

  13. Oxidation Behavior and Chlorination Treatment to Improve Oxidation Resistance of Nb-Mo-Si-B Alloys

    SciTech Connect

    Behrani, Vikas

    2004-01-01

    This thesis is written in an alternate format. The thesis is composed of a general introduction, two original manuscripts, and a general conclusion. References cited within each chapter are given at the end of each chapter. The general introduction starts with the driving force behind this research, and gives an overview of previous work on boron doped molybdenum silicides, Nb/Nb5Si3 composites, boron modified niobium silicides and molybdenum niobium silicides. Chapter 2 focuses on the oxidation behavior of Nb-Mo-Si-B alloys. Chapter 3 contains studies on a novel chlorination technique to improve the oxidation resistance of Nb-Mo-Si-B alloys. Chapter 4 summarizes the important results in this study.

  14. Rectifying Performance and Negative Differential Resistance Behavior of Doping Atoms Effect in Polyphenyls

    NASA Astrophysics Data System (ADS)

    Liu, Wenjiang; Cai, Shaohong; Deng, Xiaoqing

    2015-02-01

    The properties of two polyphenyls doped with nitrogen and boron atoms, which are connected by an alkane chain, are investigated by the non-equilibrium Green's function method combined with the density functional theory. It has been found that the doped sites have significant effects on the current-voltage characteristics. For models with the N(B) near the alkane chain, the rectification ratio is smaller, but the rectifying performance of models with the N(B) far away from the alkane chain is tremendously enhanced and rectification ratios can reach 280, alongside negative differential resistance behavior. The mechanisms for these phenomena are explained by transmission spectra, the molecular projected self-consistent Hamiltonian eigenstates, electrostatic potential distribution, and projected density of states.

  15. Water-based adhesives with tailored hydrophobic association: dilution resistance and improved setting behavior.

    PubMed

    Dundua, Alexander; Landfester, Katharina; Taden, Andreas

    2014-11-01

    Hydrophobic association and stimuli-responsiveness is a powerful tool towards water-based adhesives with strongly improved properties, which is demonstrated based on the example of hydrophobically modified alkali-soluble latexes (HASE) with modulated association. Their rheological properties are highly tunable due to the hydrophobic domains that act as physical crosslinking sites of adjustable interaction strength. Ethanol, propanol, and butanol are used as water-soluble model additives with different hydrophobicity in order to specifically target the association sites and impact the viscoelastic properties and stimuli-responsiveness. The rheological and mechanical property response upon dilution with water can be tailored, and dilution-resistant or even dilution-thickening systems are obtained. The investigations are of high importance for water-based adhesives, as our findings provide insight into general structure-property relationships to improve their setting behavior, especially upon contact with wet substrates.

  16. Resistive switching behavior and multiple transmittance states in solution-processed tungsten oxide.

    PubMed

    Wu, Wei-Ting; Wu, Jih-Jen; Chen, Jen-Sue

    2011-07-01

    In this work, a tungsten oxide (WO(x)) film is prepared using a thiourea-assisted solution process. We demonstrate a device composed of fluorine doped tin oxide (FTO)-glass/WO(x)/electrolyte/indium-tin oxide (ITO)-glass stacking electrochromic (EC) structure and Al electrodes that are locally patterned and interposed between the WO(x) film and electrolyte, which form an Al(top electrode)/WO(x)/FTO(bottom electrode) resistance random access memory (RRAM) unit. According to transmission electron microscopy and X-ray photoelectron spectroscopy analyses, the WO(x) film contains nanosize pores and metallic-tungsten nanoclusters which are scattered within the tungsten oxide layer and concentrated along the interface between the Al electrode and WO(x) film. With application of voltage to the ITO electrode, multiple transmittance states are achieved for the EC unit due to the different quantity of intercalated Li ions in the WO(x) film. As for the Al/WO(x)/FTO RRAM unit, a bipolar nonvolatile resistive switching behavior is attained by applying voltage on the Al top electrode, showing electrical bistability with an ON/OFF current ratio up to 1 × 10(4).

  17. Effect of oxygen concentration on resistive switching behavior in silicon oxynitride film

    NASA Astrophysics Data System (ADS)

    Chen, Da; Huang, Shihua; He, Lü

    2017-04-01

    SiO{}xN{}y films with different oxygen concentrations were fabricated by reactive magnetron sputtering, and the resistive switching characteristics and conduction mechanism of Cu/SiO{}xN{}y/ITO devices were investigated. The Cu/SiO{}xN{}y/ITO device with SiO{}xN{}y deposited in 0.8-sccm O{}2 flow shows a reliable resistive switching behavior, including good endurance and retention properties. As the conductivity of SiO{}xN{}y increases with the increase of the oxygen content dynamical electron trapping and detrapping is suggested to be the conduction mechanism. The temperature dependent I-V measurement indicates that the carrier transport can be ascribed to the hopping conduction rather than the metallic conductive filament. Project supported by the Natural Science Foundation of Zhejiang Province (No. LY17F040001), the Open Project Program of Surface Physics Laboratory (National Key Laboratory) of Fudan University (No. KF2015_02), the Open Project Program of National Laboratory for Infrared Physics, Chinese Academy of Sciences (No. M201503), the Zhejiang Provincial Science and Technology Key Innovation Team (No. 2011R50012), and the Zhejiang Provincial Key Laboratory (No. 2013E10022).

  18. Biomechanical Behavior of Extensively Restored Premolars: Cusp Deformation, Marginal Integrity, and Fracture Resistance.

    PubMed

    Barreto, Bruno de Castro Ferreira; Van Meerbeek, Bart; Van Ende, Annelies; Sousa, Silas Junior Boaventura de; Silva, Gisele Rodrigues da; Soares, Paulo Vinícius; Soares, Carlos José

    2015-06-01

    To study the biomechanical behavior of extensively restored premolars by determining the effect of the composite type, presence of cusp weakening, and compressive loading on the cusp deformation (CD), marginal integrity (MI), and fracture resistance (FR) of directly restored premolars. Forty premolars received Class II mesio-occlusal-distal (MOD) cavities and were divided into 4 groups (n = 10) in accordance with the two study variables: composite type (conventional: Filtek Z250 XT [Z250], 3M ESPE; low shrinkage: Venus Diamond [VD], Heraeus-Kulzer) and the presence of cusp weakening (with/without). Cusp deformation upon restoration was assessed using strain gauges during the restorative procedure and thereafter when the restorations were subjected to an occlusal load of 100 N. The samples were subjected to thermal and mechanical cycling. Epoxy resin replicas of the proximal tooth/restoration interfaces were made to analyze the marginal integrity (MI) using scanning electron microscopy. To determine the fracture resistance (FR), the teeth were loaded at a crosshead speed of 0.5 mm/min until fracture. The conventional composite Z250 had higher CD, lower MI, and lower FR than the low-shrinkage composite VD. Cusp weakening had no influence on CD, but MI and FR decreased. The low-shrinkage composite VD performed better in restoring extensively destroyed premolars than did Z250.

  19. Surface working of 304L stainless steel: Impact on microstructure, electrochemical behavior and SCC resistance

    SciTech Connect

    Acharyya, S.G.; Khandelwal, A.; Kain, V.; Kumar, A.; Samajdar, I.

    2012-10-15

    The effect of surface working operations on the microstructure, electrochemical behavior and stress corrosion cracking resistance of 304L stainless steel (SS) was investigated in this study. The material was subjected to (a) solution annealing (b) machining and (c) grinding operations. Microstructural characterization was done using stereo microscopy and electron back scattered diffraction (EBSD) technique. The electrochemical nature of the surfaces in machined, ground and solution annealed condition were studied using potentiodynamic polarization and scanning electrochemical microscopy (SECM) in borate buffer solution. The stress corrosion cracking resistance of 304L SS in different conditions was studied by exposing the samples to boiling MgCl{sub 2} environment. Results revealed that the heavy plastic deformation and residual stresses present near the surface due to machining and grinding operations make 304L SS electrochemically more active and susceptible to stress corrosion cracking. Ground sample showed highest magnitude of current density in the passive potential range followed by machined and solution annealed 304L SS. Micro-electrochemical studies established that surface working promotes localized corrosion along the surface asperities which could lead to crack initiation. - Highlights: Black-Right-Pointing-Pointer Machining/grinding produce extensive grain fragmentation near the surface of 304L SS. Black-Right-Pointing-Pointer Machining/grinding result in martensitic transformation near the surface of 304L SS. Black-Right-Pointing-Pointer Machining/grinding drastically reduce the SCC resistance of 304L SS in chloride. Black-Right-Pointing-Pointer Machining/grinding make the surface of 304L SS electrochemically much more active. Black-Right-Pointing-Pointer SECM study reveal that preferential dissolution takes place along surface asperities.

  20. Carbide Precipitation Behavior and Wear Resistance of a Novel Roller Steel

    NASA Astrophysics Data System (ADS)

    Guo, Jing; Li, Qiang; Qu, Hongwei; Liu, Ligang; Yang, Qingxiang

    2013-06-01

    High speed steel, which contains more alloy elements, cannot be used to manufacture the forged work roll. Therefore, a novel roller steel was designed on the basis of W6Mo5Cr4V2 (M2) steel. In this study, the carbide precipitation behavior and wear resistance of the novel roller steel were investigated. The Fe-C isopleths were calculated by Thermo-Calc to determine the carbide types, which were precipitated at different temperatures. The phase transformation temperatures were measured by differential scanning calorimeter and then the characteristic temperatures were designed. The phase structures quenched from the characteristic temperatures were measured by x-ray diffraction and transmission electron microscopy. The typical microstructures were observed by field emission scanning electron microscopy with Energy Disperse Spectroscopy. The hardness and wear resistance of the novel roller steel were measured. The results show that the precipitation temperatures of austenite, MC, M6C, M23C6, and ferrite are 1360, 1340, 1230, 926, and 843 °C respectively. When the specimen is quenched from 1300 °C, only MC precipitates from the matrix. At 1220 °C, MC and M2C precipitate. At 1150 °C, all of MC, M2C and M6C precipitate. Relationship between mass fraction of different phases and temperature were also simulated by Thermo-Calc. The hardness of the novel roller steel is a little lower than that of M2 steel, however, the wear resistance of the novel roller steel is a little higher than that of M2 steel with the increase of wear time.

  1. Photo-electron double regulated resistive switching memory behaviors of Ag/CuWO4/FTO device

    NASA Astrophysics Data System (ADS)

    Sun, B.; Jia, X. J.; Wu, J. H.; Chen, P.

    2015-12-01

    In this work, the CuWO4 film based resistive switching memory capacitors were fabricated with hydrothermal and spin-coating approaches. The device exhibits excellent photo-electron double controlled resistive switching memory characteristics with OFF/ON resistance ratio of ~103. It is believed that the interface of CuWO4 and FTO is responsible for such a switching behavior and it can be described by the Schottky-like barriers model. This study is useful for exploring the multifunctional materials and their applications in photo-electron double controlled nonvolatile memory devices.

  2. Resistance switching and retention behaviors in polycrystalline La-doped SrTiO3 ceramics chip devices

    NASA Astrophysics Data System (ADS)

    Hirose, Sakyo; Nakayama, Akinori; Niimi, Hideaki; Kageyama, Keisuke; Takagi, Hiroshi

    2008-09-01

    Resistance switching and retention behaviors in polycrystalline La-doped SrTiO3 ceramics have been investigated. La-doped SrTiO3 ceramics exhibits resistance switching as large as that of thin-film devices and exhibits a long-term memory effect of over 5 h. By means of a complex impedance analysis, it was clarified that these resistance changes can be reasonably attributed to the change in the electrical potential barrier at the interfaces and the resistance of the grain boundary changes remarkably by the application of voltage pulses. From the resistance retention properties at various temperatures, it was found that the high-resistance state is very stable even at 125 °C, whereas the resistance in the low-resistance state increases with time and its relaxation speed becomes remarkably faster with increasing temperatures. These results imply that the migration of the point defects could change the distribution of the space charge near the interface, resulting in a change in the interface resistances.

  3. Correlation between structural properties and resistivity critical behavior in SrRuO3 thin films.

    PubMed

    Galdi, A; Orgiani, P; Maritato, L; Méchin, L

    2012-10-31

    SrRuO(3) is a strong itinerant ferromagnet showing many features of 'bad metals' together with Fermi liquid behavior at very low temperature. The intriguing magnetic and transport properties of SrRuO(3) are tightly related to structure, as commonly observed in transition metal oxides. Here we report on the correlation of structural parameters (lattice constant and surface roughness) with the critical behavior of resistivity at the Curie point in SrRuO(3) thin films deposited on (001) SrTiO(3) by PLD. By varying the deposition conditions we were able to obtain a wide variety of structural properties in our samples, thus allowing us to perform a systematic study. Our analysis demonstrates the direct correlation between the critical temperature T(P) and the lattice out-of-plane parameter. Furthermore, the value of the critical exponent λ is proved to be a good physical parameter to quantify the microscopic order of SrRuO(3) samples.

  4. Electrochemical behavior of tube-fin assembly for an aluminum automotive condenser with improved corrosion resistance

    NASA Astrophysics Data System (ADS)

    Pech-Canul, M. A.; Guía-Tello, J. C.; Pech-Canul, M. I.; Aguilar, J. C.; Gorocica-Díaz, J. A.; Arana-Guillén, R.; Puch-Bleis, J.

    An aluminum automotive condenser was designed to exhibit high corrosion resistance in the seawater acetic acid test (SWAAT) combining zinc coated microchannel tubes and fins made with AA4343/AA3003(Zn)/AA4343 brazing sheet. Electrochemical measurements in SWAAT solution were carried out under laboratory conditions using tube-fin assembly and individual fin and tube samples withdrawn from the condenser core. The aim was to gain information on the protective role of the zinc sacrificial layer and about changes in corrosion behavior as a function of immersion time. External corrosion of the tube-fin system was simulated by immersion of mini-core samples under open circuit conditions. The corrosion rate increased rapidly during the first 6 h and slowly afterwards. The short time behavior was related to the dissolution of the oxide film and fast dissolution of the outermost part of the zinc diffusion layer. With the aid of cross-sectional depth corrosion potential profiles, it was shown that as the sacrificial layer gets dissolved, the surface concentration of zinc decreases and the potential shifts to less negative values. The results of galvanic coupling of tube and fins in a mini-cell showed that the tube became the anode while the fins exhibited cathodic behavior. An evolution in the galvanic interaction was observed, due to the progressive dissolution of the sacrificial zinc layer. The difference of uncoupled potentials between tube and fins decreased from 71 mV to 32 mV after 84 h of galvanic coupling. At the end of such period there was still a part of the zinc sacrificial layer remaining which would serve for protection of the tube material for even longer periods and there were indications of slight corrosion in the fins.

  5. Directions in Specialized Cognitive Behavior Therapy for Resistant Obsessive-Compulsive Disorder: Theory and Practice of Two Approaches

    ERIC Educational Resources Information Center

    Sookman, Debbie; Steketee, Gail

    2007-01-01

    This paper discusses specialized approaches developed for patients with obsessive-compulsive disorder (OCD) who are resistant to cognitive behavior therapy (CBT). Following a review of theoretical and outcome research, two approaches developed to resolve persistent OCD are described and illustrated. Cognitive therapy (CT) designed to address…

  6. Directions in Specialized Cognitive Behavior Therapy for Resistant Obsessive-Compulsive Disorder: Theory and Practice of Two Approaches

    ERIC Educational Resources Information Center

    Sookman, Debbie; Steketee, Gail

    2007-01-01

    This paper discusses specialized approaches developed for patients with obsessive-compulsive disorder (OCD) who are resistant to cognitive behavior therapy (CBT). Following a review of theoretical and outcome research, two approaches developed to resolve persistent OCD are described and illustrated. Cognitive therapy (CT) designed to address…

  7. Resisting Pressure from Peers to Engage in Sexual Behavior: What Communication Strategies Do Early Adolescent Latino Girls Use?

    ERIC Educational Resources Information Center

    Norris, Anne E.; Pettigrew, Jonathan; Miller-Day, Michelle; Hecht, Michael L.; Hutchison, Janet; Campoe, Kristi

    2015-01-01

    A content analysis of early adolescent X-bar = 12.02 years) Latino girls' (n = 44) responses to open-ended questions embedded in an electronic survey was conducted to explore strategies girls may use to resist peer pressure with respect to sexual behavior. Analysis yielded 341 codable response units, 74% of which were consistent with the REAL…

  8. Resisting Pressure from Peers to Engage in Sexual Behavior: What Communication Strategies Do Early Adolescent Latino Girls Use?

    ERIC Educational Resources Information Center

    Norris, Anne E.; Pettigrew, Jonathan; Miller-Day, Michelle; Hecht, Michael L.; Hutchison, Janet; Campoe, Kristi

    2015-01-01

    A content analysis of early adolescent X-bar = 12.02 years) Latino girls' (n = 44) responses to open-ended questions embedded in an electronic survey was conducted to explore strategies girls may use to resist peer pressure with respect to sexual behavior. Analysis yielded 341 codable response units, 74% of which were consistent with the REAL…

  9. Study of self-compliance behaviors and internal filament characteristics in intrinsic SiOx-based resistive switching memory

    NASA Astrophysics Data System (ADS)

    Chang, Yao-Feng; Fowler, Burt; Zhou, Fei; Chen, Ying-Chen; Lee, Jack C.

    2016-01-01

    Self-compliance characteristics and reliability optimization are investigated in intrinsic unipolar silicon oxide (SiOx)-based resistive switching (RS) memory using TiW/SiOx/TiW device structures. The program window (difference between SET voltage and RESET voltage) is dependent on external series resistance, demonstrating that the SET process is due to a voltage-triggered mechanism. The program window has been optimized for program/erase disturbance immunity and reliability for circuit-level applications. The SET and RESET transitions have also been characterized using a dynamic conductivity method, which distinguishes the self-compliance behavior due to an internal series resistance effect (filament) in SiOx-based RS memory. By using a conceptual "filament/resistive gap (GAP)" model of the conductive filament and a proton exchange model with appropriate assumptions, the internal filament resistance and GAP resistance can be estimated for high- and low-resistance states (HRS and LRS), and are found to be independent of external series resistance. Our experimental results not only provide insights into potential reliability issues but also help to clarify the switching mechanisms and device operating characteristics of SiOx-based RS memory.

  10. Drug resistant HIV: Behaviors and characteristics among Los Angeles men who have sex with men with new HIV diagnosis.

    PubMed

    Gorbach, Pamina M; Javanbakht, Marjan; Bornfleth, Lorelei; Bolan, Robert K; Lewis Blum, Martha

    2017-01-01

    Epidemiology of drug resistant HIV has focused on trends and less attention has been given to identification of factors, especially behaviors including substance use, in acquisition of drug-resistant HIV. From 2009 to 2012 The Metromates Study enrolled and followed for one year men who have sex with men (MSM) seeking testing for HIV in a community clinic in Los Angeles assessing those testing positive for acute and recent HIV infection. Behavioral data were collected via Computer-Assisted Self-Interview from 125 classified as newly HIV infected and 91 as chronically infected (newly HIV-diagnosed); specimens were available and viable for resistance testing for 154 of the 216 HIV positives with new diagnoses. In this community clinic we found prevalence of resistance among MSM with new HIV-diagnosis was 19.5% (n = 30/154) with no difference by recency of HIV infection. Sexual partnership characteristics were associated with resistance; those who reported transgendered sex partners had a higher prevalence of resistance as compared to those who did not report transgendered sex partners (40% vs. 17%; p value = 0.04), while those who reported having a main partner had a lower prevalence of drug resistance (12% vs. 24%; p value = 0.07). In multivariable analyses adjusting for HIV recency and antiviral use, reporting a main partner decreased odds [adjusted odds ratio (AOR) 0.34; 95% confidence interval (CI) 0.13-0.87], reporting a transgendered partnered increased odds (AOR = 3.37; 95% CI 0.95-12.43); and being African American increased odds of drug resistance (AOR = 5.63, 95%CI 1.41-22.38). This suggests African American MSM and TG individuals in Los Angeles represent pockets of exceptional risk that will require special approaches to prevention and care to enhance their own health and reduce their likelihood to support transmission of drug resistance in the US.

  11. Drug resistant HIV: Behaviors and characteristics among Los Angeles men who have sex with men with new HIV diagnosis

    PubMed Central

    Gorbach, Pamina M.; Javanbakht, Marjan; Bornfleth, Lorelei; Bolan, Robert K.; Lewis Blum, Martha

    2017-01-01

    Epidemiology of drug resistant HIV has focused on trends and less attention has been given to identification of factors, especially behaviors including substance use, in acquisition of drug-resistant HIV. From 2009 to 2012 The Metromates Study enrolled and followed for one year men who have sex with men (MSM) seeking testing for HIV in a community clinic in Los Angeles assessing those testing positive for acute and recent HIV infection. Behavioral data were collected via Computer-Assisted Self-Interview from 125 classified as newly HIV infected and 91 as chronically infected (newly HIV-diagnosed); specimens were available and viable for resistance testing for 154 of the 216 HIV positives with new diagnoses. In this community clinic we found prevalence of resistance among MSM with new HIV-diagnosis was 19.5% (n = 30/154) with no difference by recency of HIV infection. Sexual partnership characteristics were associated with resistance; those who reported transgendered sex partners had a higher prevalence of resistance as compared to those who did not report transgendered sex partners (40% vs. 17%; p value = 0.04), while those who reported having a main partner had a lower prevalence of drug resistance (12% vs. 24%; p value = 0.07). In multivariable analyses adjusting for HIV recency and antiviral use, reporting a main partner decreased odds [adjusted odds ratio (AOR) 0.34; 95% confidence interval (CI) 0.13–0.87], reporting a transgendered partnered increased odds (AOR = 3.37; 95% CI 0.95–12.43); and being African American increased odds of drug resistance (AOR = 5.63, 95%CI 1.41–22.38). This suggests African American MSM and TG individuals in Los Angeles represent pockets of exceptional risk that will require special approaches to prevention and care to enhance their own health and reduce their likelihood to support transmission of drug resistance in the US. PMID:28333950

  12. Unipolar resistive switching characteristics and scaling behaviors in La2Mo2O9 thin films for nonvolatile memory applications

    NASA Astrophysics Data System (ADS)

    Hu, L.; Lin, G. T.; Luo, X.; Wei, R. H.; Zhu, X. B.; Song, W. H.; Dai, J. M.; Sun, Y. P.

    2016-12-01

    La2Mo2O9 (LMO) thin films have been deposited on Pt/Ti/SiO2/Si substrates by pulsed laser deposition and the resistive switching (RS) characteristics of the Au/LMO/Pt devices has been investigated. The Au/LMO/Pt devices show excellent unipolar RS characteristics with high resistance ratio between high resistance state and low resistance state (LRS), good endurance, and retention performances. The results of temperature dependence of resistance and x-ray photoelectron spectroscopy suggest that the observed RS characteristics can be explained by the formation and rupture of conducting filaments composed of oxygen vacancies. Furthermore, the plot of the reset current (IR) as a function of the third harmonic coefficient (B0) caused by Joule heating during the reset process shows scaling behavior with a power law of I R ∝ B0 - δ . The IR and reset power (PR) can also be scaled to the resistance in LRS (R0), i.e., I R ( P R ) ∝ R0 - α ( β ) . The observed scaling behaviors indicate the importance of the Joule heating for the RS characteristics of Au/LMO/Pt devices. These results demonstrate the potential application of LMO thin film in a nonvolatile memory device.

  13. Nanocrystalline Si pathway induced unipolar resistive switching behavior from annealed Si-rich SiNx/SiNy multilayers

    NASA Astrophysics Data System (ADS)

    Jiang, Xiaofan; Ma, Zhongyuan; Yang, Huafeng; Yu, Jie; Wang, Wen; Zhang, Wenping; Li, Wei; Xu, Jun; Xu, Ling; Chen, Kunji; Huang, Xinfan; Feng, Duan

    2014-09-01

    Adding a resistive switching functionality to a silicon microelectronic chip is a new challenge in materials research. Here, we demonstrate that unipolar and electrode-independent resistive switching effects can be realized in the annealed Si-rich SiNx/SiNy multilayers with high on/off ratio of 109. High resolution transmission electron microscopy reveals that for the high resistance state broken pathways composed of discrete nanocrystalline silicon (nc-Si) exist in the Si nitride multilayers. While for the low resistance state the discrete nc-Si regions is connected, forming continuous nc-Si pathways. Based on the analysis of the temperature dependent I-V characteristics and HRTEM photos, we found that the break-and-bridge evolution of nc-Si pathway is the origin of resistive switching memory behavior. Our findings provide insights into the mechanism of the resistive switching behavior in nc-Si films, opening a way for it to be utilized as a material in Si-based memories.

  14. Deltamethrin-mediated survival, behavior, and oenocyte morphology of insecticide-susceptible and resistant yellow fever mosquitos (Aedes aegypti).

    PubMed

    Marriel, Nadja Biondine; Tomé, Hudson Vaner Ventura; Guedes, Raul Carvalho Narciso; Martins, Gustavo Ferreira

    2016-06-01

    Insecticide use is the prevailing control tactic for the mosquito Aedes aegypti, a vector of several human viruses, which leads to ever-increasing problems of insecticide resistance in populations of this insect pest species. The underlying mechanisms of insecticide resistance may be linked to the metabolism of insecticides by various cells, including oenocytes. Oenocytes are ectodermal cells responsible for lipid metabolism and detoxification. The goal of this study was to evaluate the sublethal effects of deltamethrin on survival, behavior, and oenocyte structure in the immature mosquitoes of insecticide-susceptible and resistant strains of A. aegypti. Fourth instar larvae (L4) of both strains were exposed to different concentrations of deltamethrin (i.e., 0.001, 0.003, 0.005, and 0.007 ppm). After exposure, L4 were subjected to behavioral bioassays. Insecticide effects on cell integrity after deltamethrin exposure (at 0.003 or 0.005 ppm) were assessed by processing pupal oenocytes for transmission electron microscopy or TUNEL reaction. The insecticide resistant L4 survived all the tested concentrations, whereas the 0.007-ppm deltamethrin concentration had lethal effects on susceptible L4. Susceptible L4 were lethargic and exhibited less swimming activity than unexposed larvae, whereas the resistant L4 were hyperexcited following exposure to 0.005 ppm deltamethrin. No sublethal effects and no significant cell death were observed in the oenocytes of either susceptible or resistant insects exposed to deltamethrin. The present study illustrated the different responses of susceptible and resistant strains of A. aegypti following exposure to sublethal concentration of deltamethrin, and demonstrated how the behavior of the immature stage of the two strains varied, as well as oenocyte structure following insecticide exposure.

  15. Acoustic emission analysis of crack resistance and fracture behavior of 20GL steel having the gradient microstructure and strength

    NASA Astrophysics Data System (ADS)

    Nikulin, S.; Nikitin, A.; Belov, V.; Rozhnov, A.; Turilina, V.; Anikeenko, V.; Khatkevich, V.

    2017-07-01

    The crack resistances as well as fracture behavior of 20GL steel quenched with a fast-moving water stream and having gradient microstructure and strength are analyzed. Crack resistance tests with quenched and normalized flat rectangular specimens having different cut lengths loaded by three-point bending with acoustic emission measurements have been performed. The critical J-integral has been used as the crack resistance parameter of the material. Quenching with a fast moving water stream leads to gradient (along a specimen wall thickness) strengthening of steel due to highly refined gradient microstructure formation of the troostomartensite type. Quenching with a fast-moving water stream increases crack resistance Jc , of 20GL steel by a factor of ∼ 1.5. The fracture accrues gradually with the load in the normalized specimens while the initiated crack is hindered in the variable ductility layer and further arrested in the more ductile core in the quenched specimens.

  16. Using short vignettes to disentangle perceived capability from motivation: a test using walking and resistance training behaviors.

    PubMed

    Rhodes, Ryan E; Williams, David M; Mistry, Chetan D

    2016-07-01

    Self-efficacy is arguably the strongest correlate of physical activity, yet some researchers suggest this is because the construct confounds ability with motivation. We examine a more circumscribed construct, called perceived capability (PC), meant to measure ability but not motivation and propose that the construct will not be related to unskilled physical activities but may be linked to skilled behaviors. The purpose of this paper was to examine whether a PC construct can be stripped of motivation using a vignette approach in both walking and resistance training behaviors. Participants were a random sample of 248 university students, who were then randomly assigned to either answer resistance training or walking behavior questions. Both groups completed a PC measure and reasons for their answer before and after reading a vignette that clarified the phrasing of capability to a literal use of the term. PC was significantly (p < .01) higher post- compared to pre-vignette and the differences were greater (p < .01) for walking than for resistance training. PC had significantly (p < .01) smaller correlations with intention and self-reported behavior post-disambiguation, which resulted in a null relationship with walking but a small correlation with resistance training behavior. When PC was combined with intention to predict behavior, however, there was no significant (p > .05) difference in the amount of variance explained pre- to post-vignette. Thought listing showed that participants did not report capability barriers to walking and over half of the sample construed capability as motivation/other priorities pre-vignette. The findings support use of a vignette approach for researchers who wish to disentangle the assessment of PC from motivation while creating no overall loss in explained variance of physical activity.

  17. Men’s Condom Use Resistance: Alcohol Effects on Theory of Planned Behavior Constructs

    PubMed Central

    Davis, Kelly Cue; Jacques-Tiura, Angela J.; Stappenbeck, Cynthia A.; Danube, Cinnamon L.; Morrison, Diane M.; Norris, Jeanette; George, William H.

    2015-01-01

    Objective This study is a novel investigation of 1) the utility of the Theory of Planned Behavior (TPB) to predict men’s condom use resistance (CUR; i.e., attempts to avoid condom use with a partner who wants to use one) and 2) the effects of alcohol on endorsement of TPB-CUR constructs. Methods Using an alcohol administration protocol, a between- and within-subjects experiment was conducted with a community sample of 312 young male non-problem drinkers who have sex with women. After assessing endorsement of TPB-CUR constructs (e.g., attitudes, norms, self-efficacy, control, and intentions) in a sober state, beverage condition was experimentally manipulated between subjects and endorsement of TPB-CUR constructs was reassessed. Results Analyses included repeated measures MANOVAs with beverage condition (no alcohol vs. alcohol) as the between-subjects factor and time (pre-beverage vs. post-beverage) as the within-subjects factor. Between-subjects, intoxicated participants reported significantly stronger CUR intentions, more favorable CUR attitudes and normative perceptions, and greater CUR self-efficacy than sober participants. There were significant within-subject changes for CUR intentions, attitudes, normative perceptions, and self-efficacy. Neither between- nor within-subjects effects were found for CUR control. An exploratory multi-group path analysis indicated that the relationships among the TPB-CUR constructs were similar for alcohol and no alcohol groups. Conclusions Findings indicated that alcohol intoxication increased men’s CUR intentions and self-efficacy and led to more positive CUR attitudes and norms, yet had no effect on CUR control. Future research should examine whether there are similar effects of intoxication on TPB constructs related to other sexual risk behaviors. PMID:26348499

  18. The Role of Hidden Curricula on the Resistance Behavior of Undergraduate Students in Psychological Counseling and Guidance at a Turkish University

    ERIC Educational Resources Information Center

    Yuksel, Sedat

    2006-01-01

    Student resistance can be a very important problem for the instructors in universities. Student resistance includes the conscious and preplanned behaviors towards the information presented to them in the classroom and the institutional practices. Typically, student resistance takes the form of passive or active non-compliance with roles and…

  19. THE BEHAVIOR OF TRANSVERSE WAVES IN NONUNIFORM SOLAR FLUX TUBES. I. COMPARISON OF IDEAL AND RESISTIVE RESULTS

    SciTech Connect

    Soler, Roberto; Terradas, Jaume; Oliver, Ramón; Goossens, Marcel

    2013-11-10

    Magnetohydrodynamic (MHD) waves are ubiquitously observed in the solar atmosphere. Kink waves are a type of transverse MHD waves in magnetic flux tubes that are damped due to resonant absorption. The theoretical study of kink MHD waves in solar flux tubes is usually based on the simplification that the transverse variation of density is confined to a nonuniform layer much thinner than the radius of the tube, i.e., the so-called thin boundary approximation. Here, we develop a general analytic method to compute the dispersion relation and the eigenfunctions of ideal MHD waves in pressureless flux tubes with transversely nonuniform layers of arbitrary thickness. Results for kink waves are produced and compared with fully numerical resistive MHD eigenvalue computations in the limit of small resistivity. We find that the frequency and resonant damping rate are the same in both ideal and resistive cases. The actual results for thick nonuniform layers deviate from the behavior predicted in the thin boundary approximation and strongly depend on the shape of the nonuniform layer. The eigenfunctions in ideal MHD are very different from those in resistive MHD. The ideal eigenfunctions display a global character regardless of the thickness of the nonuniform layer, while the resistive eigenfunctions are localized around the resonance and are indistinguishable from those of ordinary resistive Alfvén modes. Consequently, the spatial distribution of wave energy in the ideal and resistive cases is dramatically different. This poses a fundamental theoretical problem with clear observational consequences.

  20. Resistance switching behavior of ZnO resistive random access memory with a reduced graphene oxide capping layer

    NASA Astrophysics Data System (ADS)

    Lin, Cheng-Li; Chang, Wei-Yi; Huang, Yen-Lun; Juan, Pi-Chun; Wang, Tse-Wen; Hung, Ke-Yu; Hsieh, Cheng-Yu; Kang, Tsung-Kuei; Shi, Jen-Bin

    2015-04-01

    In this work, we investigate the characteristics of ZnO resistive random access memory (RRAM) with a reduced graphene oxide (rGO) capping layer and the polarity effect of the SET/RESET bias on the RRAM. The rGO film insertion enhances the stability of the current-voltage (I-V) switching curve and the superior resistance ratio (˜105) of high-resistance state (HRS) to low-resistance state (LRS). Using the appropriate polarity of the SET/RESET bias applied to the rGO-capped ZnO RRAM enables the oxygen ions to move mainly at the interface of the rGO and ZnO films, resulting in the best performance. Presumably, the rGO film acts as an oxygen reservoir and enhances the easy in and out motion of the oxygen ions from the rGO film. The rGO film also prevents the interaction of oxygen ions and the Al electrode, resulting in excellent performance. In a pulse endurance test, the rGO-capped ZnO RRAM reveals superior endurance of up to 108 cycles over that of the ZnO RRAM without rGO insertion (106 cycles).

  1. Effect of Cu content on wear resistance and mechanical behavior of Ti-Cu binary alloys

    NASA Astrophysics Data System (ADS)

    Yu, Feifei; Wang, Hefeng; Yuan, Guozheng; Shu, Xuefeng

    2017-04-01

    Arc melting with nonconsumable tungsten electrode and water-cooled copper crucible was used to fabricate Ti-Cu binary alloys with different Cu contents in an argon atmosphere. The compositions and phase structures of the fabricated alloys were investigated by glow discharge optical emission spectroscopy (GDOES) and X-ray diffraction (XRD). Nanoindentation tests through continuous stiffness measurement were then performed at room temperature to analyze the mechanical behaviors of the alloys. Results indicated that the composition of each Ti-Cu binary alloy was Ti(100- x) Cu x ( x = 43, 60, 69, and 74 at.%). The XRD analysis results showed that the alloys were composed of different phases, indicating that different Cu contents led to the variations in alloy hardness. The wear tests results revealed that elemental Cu positively affects the wear resistance properties of the Ti-Cu alloys. Nanoindentation testing results showed that the moduli of the Ti-Cu alloys were minimally changed at increasing Cu content, whereas their hardness evidently increased according to the wear test results.

  2. The behavior of series resistance of a p-n junction: the diode and the solar cell cases

    NASA Astrophysics Data System (ADS)

    Bueno, Poliana H.; Costa, Diogo F.; Eick, Alexander; Carvalho, André; Monteiro, Davies W. L.

    2016-03-01

    This paper presents a comparison of the impact of the internal parasitic series resistance of a p-n junction, as seen from the microelectronics and photovoltaic communities. The elusive thermal behavior of the aforementioned resistance gave this work its origin. Each community uses a different approach to interpret the operational current-voltage behavior of a p-n junction, which might lead to confusion, since scientists and engineers of these two realms seldom interact. An improvement in the understanding of the different approaches will help one to better model the performance of devices based on p-n junctions and therefore it will favor the performance predictions of photovoltaic cells. For diodes, series resistance is usually determined from a specific forward-bias region of the I-V curve on a semi-logarithmic scale. However, in Photovoltaics this region is not commonly reported and therefore other methods to determine Rs are employed. We mathematically modeled an experimentally obtained I-V curve with various pairs of the ideality factor and Rs and found that more than one pair accurately synthesizes the measured curve. We can conclude that the reported series resistance not only depends on physical parameters, e.g. temperature or irradiance, but also on fitting parameters, i.e. the ideality factor. Generally the behavior of a p-n junction depends on its operating conditions and electrical modeling.

  3. Severely Heat Injured Survivors of E. coli O157:H7 ATCC 43888 Display Variable and Heterogeneous Stress Resistance Behavior

    PubMed Central

    Gayán, Elisa; Govers, Sander K.; Michiels, Chris W.; Aertsen, Abram

    2016-01-01

    Although minimal food processing strategies aim to eliminate foodborne pathogens and spoilage microorganisms through a combination of mild preservation techniques, little is actually known on the resistance behavior of the small fraction of microorganisms surviving an inimical treatment. In this study, the conduct of severely heat stressed survivors of E. coli O157:H7 ATCC 43888, as an indicator for the low infectious dose foodborne enterohemorrhagic strains, was examined throughout their resuscitation and outgrowth. Despite the fact that these survivors were initially sublethally injured, they were only marginally more sensitive to a subsequent heat treatment and actually much more resistant to a subsequent high hydrostatic pressure (HHP) shock in comparison with unstressed control cells. Throughout further resuscitation, however, their initial HHP resistance rapidly faded out, while their heat resistance increased and surpassed the initial heat resistance of unstressed control cells. Results also indicated that the population eventually emerging from the severely heat stressed survivors heterogeneously consisted of both growing and non-growing cells. Together, these observations provide deeper insights into the particular behavior and heterogeneity of stressed foodborne pathogens in the context of food preservation. PMID:27917163

  4. Temperature dependences of ferroelectricity and resistive switching behavior of epitaxial BiFeO3 thin films

    NASA Astrophysics Data System (ADS)

    Lu, Zeng-Xing; Song, Xiao; Zhao, Li-Na; Li, Zhong-Wen; Lin, Yuan-Bin; Zeng, Min; Zhang, Zhang; Lu, Xu-Bing; Wu, Su-Juan; Gao, Xing-Sen; Yan, Zhi-Bo; Liu, Jun-Ming

    2015-10-01

    We investigate the resistive switching and ferroelectric polarization properties of high-quality epitaxial BiFeO3 thin films in various temperature ranges. The room temperature current-voltage (I-V) curve exhibits a well-established polarization-modulated memristor behavior. At low temperatures (< 253 K), the I-V curve shows an open circuit voltage (OCV), which possibly originates from the dielectric relaxation effects, accompanied with a current hump due to the polarization reversal displacement current. While at relative higher temperatures (> 253 K), the I-V behaviors are governed by both space-charge-limited conduction (SCLC) and Ohmic behavior. The polarization reversal is able to trigger the conduction switching from Ohmic to SCLC behavior, leading to the observed ferroelectric resistive switching. At a temperature of > 298 K, there occurs a new resistive switching hysteresis at high bias voltages, which may be related to defect-mediated effects. Project supported by the National Natural Science Foundation of China (Grant Nos. 51272078 and 51332007), the State Key Program for Basic Research of China (Grant No 2015CB921202), the Guangdong Provincial Universities and Colleges Pearl River Scholar Funded Scheme, China (2014), the International Science & Technology Cooperation Platform Program of Guangzhou, China (Grant No. 2014J4500016), and the Program for Changjiang Scholars and Innovative Research Team in University of China (Grant No. IRT1243).

  5. Dissolution behavior of chemically amplified resist for advanced mask- and NIL mold-making as studied by dissolution rate monitor

    NASA Astrophysics Data System (ADS)

    Takeshi, Kazumasa; Oono, Kazuto; Negishi, Yoshiyuki; Inokuchi, Daisuke; Tanaka, Keishi; Tamura, Akira

    2006-05-01

    The dissolution behaviors of chemically amplified resists for electron beam lithography (EB CARs) have been investigated using the technique of quartz crystal microbalance (QCM) method. We report the first direct measurement of the dissolution rate of EB CARs and the comparison with CAR of using KrF exposure in wafer fabrication. The EB CAR for nano-imprint lithography mold making was also evaluated by this technique, and then resolved 50 nm line and space patterns using conventional 50 KV variable shape beam writing system. The understanding of dissolution kinetics of EB CARs is capable of designing high performance resists in near future.

  6. Testing the Effectiveness of Intervention Programs on Children's Compliance-Resisting Behaviors.

    ERIC Educational Resources Information Center

    McQuillen, Jeffrey S.; And Others

    A study examined the effectiveness of a resistance-based prevention program to increase subjects' ability to comprehend and apply resistance skills. Subjects were 30 participants in kindergarten through third grade. Fifteen subjects received resistance-based prevention training from the We Help Ourselves (WHO) program. The remaining 15 subjects…

  7. Controllable Negative Differential Resistance Behavior of an Azobenzene Molecular Device Induced by Different Molecule-Electrode Distances

    NASA Astrophysics Data System (ADS)

    Fan, Zhi-Qiang; Zhang, Zhen-Hua; Qiu, Ming; Deng, Xiao-Qing; Tang, Gui-Ping

    2012-07-01

    We report the ab initio calculations of transport behaviors of an azobenzene molecular device which is similar to the experimental configurations. The calculated results show that the transport behaviors of the device are sensitive to the molecule-electrode distance and the currents will drop rapidly when the molecule-electrode distance changes from 1.7 Å to 2.0 Å. More interestingly, the negative differential resistance behavior can be found in our device. Nevertheless, it is not the inherent property of an azobenzene molecular device but an effect of the molecule-electrode distance. Detailed analyses of the molecular projected self-consistent Hamiltonian states and the transmission spectra of the system reveal the physical mechanism of these behaviors.

  8. Predictors of self-protective behaviors in non-sexual violent encounters: the role of victim sex in understanding resistance.

    PubMed

    Powers, Ráchael A

    2014-11-01

    Self-protective behaviors are actions that victims take in a violent encounter to thwart the attack or avoid/minimize injury. This study examines the predictors of self-protective behaviors in non-sexual assault incidents with a particular focus on how the sex of the victim may moderate these conclusions. Non-sexual assault incidents in the National Crime Victimization Survey were analyzed (n=16,309) and four categories of self-protective behaviors were regressed on a variety of predictors using multivariate probit models. A variety of pre-assault factors (e.g., demographic characteristics), situational characteristics (e.g., location of assault), and the relationship between the victim and offender are associated with the use of resistance. Situational characteristics emerged as the most consistent and strongest predictors of self-protective behaviors. There was little evidence to suggest that separate models for male and female victims were warranted. Copyright © 2014 Elsevier Inc. All rights reserved.

  9. Stress-induced enhancement of fear conditioning and sensitization facilitates extinction-resistant and habituation-resistant fear behaviors in a novel animal model of posttraumatic stress disorder.

    PubMed

    Corley, Michael J; Caruso, Michael J; Takahashi, Lorey K

    2012-01-18

    Posttraumatic stress disorder (PTSD) is characterized by stress-induced symptoms including exaggerated fear memories, hypervigilance and hyperarousal. However, we are unaware of an animal model that investigates these hallmarks of PTSD especially in relation to fear extinction and habituation. Therefore, to develop a valid animal model of PTSD, we exposed rats to different intensities of footshock stress to determine their effects on either auditory predator odor fear extinction or habituation of fear sensitization. In Experiment 1, rats were exposed to acute footshock stress (no shock control, 0.4 mA, or 0.8 mA) immediately prior to auditory fear conditioning training involving the pairing of auditory clicks with a cloth containing cat odor. When presented to the conditioned auditory clicks in the next 5 days of extinction testing conducted in a runway apparatus with a hide box, rats in the two shock groups engaged in higher levels of freezing and head out vigilance-like behavior from the hide box than the no shock control group. This increase in fear behavior during extinction testing was likely due to auditory activation of the conditioned fear state because Experiment 2 demonstrated that conditioned fear behavior was not broadly increased in the absence of the conditioned auditory stimulus. Experiment 3 was then conducted to determine whether acute exposure to stress induces a habituation resistant sensitized fear state. We found that rats exposed to 0.8 mA footshock stress and subsequently tested for 5 days in the runway hide box apparatus with presentations of nonassociative auditory clicks exhibited high initial levels of freezing, followed by head out behavior and culminating in the occurrence of locomotor hyperactivity. In addition, Experiment 4 indicated that without delivery of nonassociative auditory clicks, 0.8 mA footshock stressed rats did not exhibit robust increases in sensitized freezing and locomotor hyperactivity, albeit head out vigilance

  10. Codes of Commitment to Crime and Resistance: Determining Social and Cultural Factors over the Behaviors of Italian Mafia Women.

    PubMed

    Cayli, Baris

    2016-01-02

    This article categorizes thirty-three women in four main Italian Mafia groups and explores social and cultural behaviors of these women. This study introduces the feminist theory of belief and action. The theoretical inquiry investigates the sometimes conflicting behaviors of women when they are subject to systematic oppression. I argue that there is a cultural polarization among the categorized sub-groups. Conservative radicals give their support to the Mafia while defectors and rebels resist the Mafia. After testing the theory, I assert that emancipation of women depends on the strength of their beliefs to perform actions against the Mafiosi culture.

  11. Codes of Commitment to Crime and Resistance: Determining Social and Cultural Factors over the Behaviors of Italian Mafia Women

    PubMed Central

    Cayli, Baris

    2016-01-01

    ABSTRACT This article categorizes thirty-three women in four main Italian Mafia groups and explores social and cultural behaviors of these women. This study introduces the feminist theory of belief and action. The theoretical inquiry investigates the sometimes conflicting behaviors of women when they are subject to systematic oppression. I argue that there is a cultural polarization among the categorized sub-groups. Conservative radicals give their support to the Mafia while defectors and rebels resist the Mafia. After testing the theory, I assert that emancipation of women depends on the strength of their beliefs to perform actions against the Mafiosi culture. PMID:26806988

  12. The Effects of Elaboration on the Strength of Doping-Related Attitudes: Resistance to Change and Behavioral Intentions.

    PubMed

    Horcajo, Javier; Luttrell, Andrew

    2016-06-01

    This experiment analyzed whether attitudes toward the legalization of several doping behaviors would resist change and predict behavioral intentions when they were initially formed through thoughtful (i.e., high elaboration) versus nonthoughtful (i.e., low elaboration) processes. Participants were randomly assigned first to a persuasive message either against or in favor of the legalization, which they read with relatively high or low degrees of deliberative thinking. Attitudes and intentions regarding legalization were assessed following that message. Next, each participant received a second message that was opposed to the first one, serving as an attack against the attitude that participants had just formed. Finally, attitudes were again assessed. As hypothesized, participants showed greater attitude-consistent intentions when they formed their initial attitudes through thoughtful (vs. nonthoughtful) consideration of the first message. Moreover, the second message resulted in greater resistance to attitude change when participants formed their initial attitudes through thoughtful (vs. nonthoughtful) processes.

  13. Making the best of a bad situation: host partial resistance and bypass of behavioral manipulation by parasites?

    PubMed

    Daoust, Simon P; King, Kayla C; Brodeur, Jacques; Roitberg, Bernard D; Roche, Benjamin; Thomas, Frédéric

    2015-09-01

    With few exceptions, parasitic manipulation dramatically reduces host fitness. That said, evidence of host resistance to behavior-manipulating parasites is scarce. Here, we suggest that the evolution of partial resistance, as well as bypass, to manipulation (PRM and BPM, respectively) represents new, seldom-explored options for parasitized hosts. Natural selection could favor hosts that partially resist certain manipulative dimensions to postpone their death and perform additional reproductive episodes (PRM). Alternatively, manipulated hosts may express novel traits that do not alter the manipulation per se but that alleviate its detrimental fitness consequences (BPM). If effective, PRM and BPM have many implications for the ecology and evolution of hosts and their parasites, especially the evolution of multidimensional manipulations.

  14. A forming-free bipolar resistive switching behavior based on ITO/V2O5/ITO structure

    NASA Astrophysics Data System (ADS)

    Wan, Zhenni; Darling, Robert B.; Majumdar, Arka; Anantram, M. P.

    2017-07-01

    Forming-free bipolar resistive switching behavior in an ITO/V2O5/ITO structure is observed. While the bottom ITO layer functions as a common ground electrode, the top ITO layer is an active element and used as an oxygen reservoir, with an additional metal electrode patterned on its top for making contact. In contrast to typical metal/transition metal oxide/metal based resistive memories, our device exhibits a low resistance state in its virgin state and is switched to a high resistance state when a forward bias of ˜+2.5 V is applied. The device can be reset to its original state at a reverse bias of ˜-1.5 V. A noticeable decrease in switching voltage with a reduced top contact area is observed, indicating a strong electric field enhanced switching mechanism. Different from the widely seen conductive filament mechanism in bipolar switching, we explain the switching behavior by the migration of oxygen ions at the top ITO/V2O5 interface. When oxygen ions are extracted to the ITO side, an interfacial layer with reduced oxidation states is formed and acts as a Schottky barrier that suppresses the current through the whole device. The results suggest future applications in low power, high speed integrated non-volatile memories.

  15. Resistive switching behavior of RF magnetron sputtered ZnO thin films

    SciTech Connect

    Rajalakshmi, R.; Angappane, S.

    2015-06-24

    The resistive switching characteristics of RF magnetron sputtered zinc oxide thin films have been studied. The x-ray diffraction studies confirm the formation of crystalline ZnO on Pt/TiO{sub 2}/SiO{sub x}/Si substrate. We have fabricated Cu/ZnO/Pt device using a shadow masking technique for resistive switching study. Our Cu/ZnO/Pt device exhibits a unipolar resistive switching behaviour. The switching observed in our device could be related to oxygen vacancies or Cu ions that generate the conducting filaments responsible for resistive switching. We found HRS to LRS resistance ratio of as high as ∼200 for our Cu/ZnO/Pt device. The higher resistance ratio and stability of Cu/ZnO/Pt device would make our RF magnetron sputtered zinc oxide thin films suitable for non volatile memory applications.

  16. Effect of Al content on impact resistance behavior of Al-Ti-B4C composite fabricated under air atmosphere.

    PubMed

    Zhao, Qian; Liang, Yunhong; Zhang, Zhihui; Li, Xiujuan; Ren, Luquan

    2016-12-01

    Reaction behavior, mechanical property and impact resistance of TiC-TiB2/Al composite reacted from Al-Ti-B4C system with various Al content via combination method of combustion synthesis and hot pressed sintering under air was investigated. Al content was the key point to the variation of mechanical property and impact resistance. Increasing Al content could increase the density, strength and toughness of the composite. Due to exorbitant ceramic content, 10wt.% and 20wt.% Al-Ti-B4C composites exhibited poor molding ability and machinability. Flexural strength, fracture toughness, compressive strength and impact toughness of 30-50wt.% Al-Ti-B4C composite were higher than those of Al matrix. The intergranular fracture dispersed and defused impact load and restricted crack extension, enhancing the impact resistance of the composite. The composite with 50wt.% Al content owned highest mechanical properties and impact resistance. The results were useful for the application of TiC-TiB2/Al composite in impact resistance field of ceramic reinforced Al matrix composite.

  17. Comparing the Predictive Capacity of Observed In-Session Resistance to Self-Reported Motivation in Cognitive Behavioral Therapy

    PubMed Central

    Westra, Henny A.

    2010-01-01

    Self-report measures of motivation for changing anxiety have been weakly and inconsistently related to outcome in cognitive behavioral therapy (CBT). While clients may not be able to accurately report their motivation, ambivalence about change may nonetheless be expressed in actual therapy sessions as opposition to the direction set by the therapist (i.e., resistance). In the context of CBT for generalized anxiety disorder, the present study compared the ability of observed in-session resistance in CBT session 1 and two self-report measures of motivation for changing anxiety (the Change Questionnaire & the Client Motivational for Therapy Scale) to (1) predict client and therapist rated homework compliance (2) predict post-CBT and one-year post-treatment worry reduction, and (3) differentiate those who received motivational interviewing prior to CBT from those who received no pretreatment. Observed in-session resistance performed very well on each index, compared to the performance of self-reported motivation which was inconsistent and weaker relative to observed resistance. These findings strongly support both clinician sensitivity to moments of client resistance in actual therapy sessions as early as session 1, and the inclusion of observational process measures in CBT research. PMID:21159325

  18. Silence of Long Noncoding RNA NEAT1 Inhibits Malignant Biological Behaviors and Chemotherapy Resistance in Gastric Cancer.

    PubMed

    Zhang, Jiale; Zhao, Bochao; Chen, Xiuxiu; Wang, Zhenning; Xu, Huimian; Huang, Baojun

    2017-04-11

    Gastric cancer (GC) is the most common solid tumor in digestive system. Nuclear-enriched abundant transcript 1 (NEAT1) gene is a lncRNA, and reveal potential oncogene role in several malignant tumors. The aim of this study is to investigate the expression and clinical significance of Nuclear Paraspeckle Assembly Transcript 1 (NEAT1) gene and its influence to malignant biologic behaviors and chemotherapy resistance to adriamycin in GC. This study found NEAT1 was up-regulated in GC tissues and cells, especially in in GC adriamycin-resistant cells. NEAT1 silence in SGC7901 cells could inhibit proliferation and invasion ability, and promote cell apoptosis significantly. NEAT1 silence in adriamycin-resistant SGC7901/ADR cells also depressed the half maximal inhibitory concentration (IC50) for adriamycin, chemotherapy resistance to adriamycin was inhibited significantly. NEAT1 knockdown promoted apoptosis in SGC7901/ADR cells induced by adriamycin. In summary, lncRNA NEAT1 is high-expressed in GC and functions as an oncogene to modulate apoptosis, invasion, proliferation and chemotherapy resistance of GC cells, which might be a novel potential therapeutic target for GC.

  19. Current Behavioral Models of Client and Consultee Resistance: A Critical Review

    ERIC Educational Resources Information Center

    Cautilli, Joe; Riley-Tillman, T. Chris; Axelrod, Saul; Hineline, Phil

    2005-01-01

    Resistance is the phenomena that occurs in the therapeutic relationship when the patient refuses to complete tasks assigned by the therapist which would benefit the patient in improving their psychological situation. Resistance is also used to describe situations in the consulting relationship where the consultee does not do what the consultant…

  20. Effects of three novel resistant black raspberry selections on Amphorophora agathonica feeding behavior and performance

    USDA-ARS?s Scientific Manuscript database

    Host plant resistance is a practical and cost-effective approach for growers to manage insect pests. Recently, three new sources of resistance in black raspberry (selections ORUS 3778-1, ORUS 3817-1, and ORUS 4109-1) against the large raspberry aphid, Amphorophora agathonica, were identified. We stu...

  1. Differential probing behavior of Blissus insularis (Hemiptera: Blissidae) on resistant and susceptible St. Augustinegrasses

    USDA-ARS?s Scientific Manuscript database

    Southern chinch bug, Blissus insularis Barber, is a severe pest of St. Augustinegrass throughout the southern United States. Host plant resistance is an environmentally friendly method to manage chinch bug infestations and is increasingly important as the southern chinch bug develops resistance to c...

  2. Development of Silica Glass Coatings on 316L SS and Evaluation of its Corrosion Resistance Behavior in Ringer's Solution

    NASA Astrophysics Data System (ADS)

    Vijayalakshmi, U.; Rajeswari, S.

    2012-12-01

    Sol-gel derived silica glasses have many promising features, including low-temperature preparation as well as chemical and physical stability. Two silica glasses with Si100 and Si80 composition were prepared to understand the factors contributing to the rate of bioactivity. The effects of pH, solution aging temperature, and molar ratio of H2O/tetraethyl orthosilicate (TEOS) were studied, and the obtained powder sample was characterized by Fourier transform infrared spectroscopy, X-ray diffraction studies, and scanning electron microscopy. The synthesized silica glasses were deposited on 316L SS by the spin coating method at the optimized speed of 2000 revolutions per minute. The corrosion resistance behavior of the coatings was determined by (1) open-circuit potential vs time of exposure, (2) electrochemical impedance spectroscopy, and (3) cyclic polarization in Ringer's solution. A higher breakdown potential ( E b) and repassivation potential ( E p) value with lower current density was obtained from cyclic polarization. Similar results were observed from impedance analysis with higher charge transfer resistance ( R ct) and lower double layer capacitance ( C dl) indicating the corrosion resistance behavior of the coatings compared with the uncoated 316L stainless steel. From the results, it was observed that both Si100 and Si80 glass coatings had a positive effect on the corrosion resistance behavior. An adhesive strength of 46 MPa and 45 MPa was obtained for the Si100 and Si80 coatings, respectively. An accelerated leach out study was carried out by impressing the potential at their breakdown potential to determine the effect of glass coating for long-term contact between the implant and a normal biological medium.

  3. Modeling and Validation of the Ecological Behavior of Wild-Type Listeria monocytogenes and Stress-Resistant Variants

    PubMed Central

    Metselaar, Karin I.; Abee, Tjakko; den Besten, Heidy M. W.

    2016-01-01

    ABSTRACT Listeria monocytogenes exhibits a heterogeneous response upon stress exposure which can be partially attributed to the presence of stable stress-resistant variants. This study aimed to evaluate the impact of the presence of stress-resistant variants of Listeria monocytogenes and their corresponding trade-offs on population composition under different environmental conditions. A set of stress robustness and growth parameters of the wild type (WT) and an rpsU deletion variant was obtained and used to model their growth behavior under combined mild stress conditions and to model their kinetics under single- and mixed-strain conditions in a simulated food chain. Growth predictions for the WT and the rpsU deletion variant matched the experimental data generally well, although some deviations from the predictions were observed. The data highlighted the influence of the environmental conditions on the ratio between the WT and variant. Prediction of performance in the simulated food chain proved to be challenging. The trend of faster growth and lower stress robustness for the WT than for the rpsU variant in the different steps of the chain was confirmed, but especially for the inactivation steps and the time needed to resume growth after an inactivation step, the experimental data deviated from the model predictions. This report provides insights into the conditions which can select for stress-resistant variants in industrial settings and discusses their potential persistence in food processing environments. IMPORTANCE Listeria monocytogenes exhibits a heterogeneous stress response which can partially be attributed to the presence of genetic variants. These stress-resistant variants survive better under severe conditions but have, on the other hand, a reduced growth rate. To date, the ecological behavior and potential impact of the presence of stress-resistant variants is not fully understood. In this study, we quantitatively assessed growth and inactivation

  4. Unipolar resistive switching behavior of amorphous YCrO{sub 3} films for nonvolatile memory applications

    SciTech Connect

    Sharma, Yogesh E-mail: rkatiyar@uprrp.edu; Misra, Pankaj; Katiyar, Ram S. E-mail: rkatiyar@uprrp.edu

    2014-08-28

    Amorphous YCrO{sub 3} (YCO) films were prepared on Pt/TiO{sub 2}/SiO{sub 2}/Si substrate by pulsed laser deposition in order to investigate resistive switching (RS) phenomenon. The Pt/YCO/Pt device showed stable unipolar RS with resistance ratio of ∼10{sup 5} between low and high resistance states, excellent endurance and retention characteristics, as well as, non-overlapping switching voltages with narrow dispersions. Based on the x-ray photoelectron spectroscopy and temperature dependent switching characteristics, observed RS was mainly ascribed to the oxygen vacancies. Moreover, current-voltage characteristics of the device in low and high resistance states were described by Ohmic and trap controlled space–charge limited conduction mechanisms, respectively.

  5. Improving outcomes for patients with medication-resistant anxiety: effects of collaborative care with cognitive behavioral therapy.

    PubMed

    Campbell-Sills, Laura; Roy-Byrne, Peter P; Craske, Michelle G; Bystritsky, Alexander; Sullivan, Greer; Stein, Murray B

    2016-12-01

    Many patients with anxiety disorders remain symptomatic after receiving evidence-based treatment, yet research on treatment-resistant anxiety is limited. We evaluated effects of cognitive behavioral therapy (CBT) on outcomes of patients with medication-resistant anxiety disorders using data from the Coordinated Anxiety Learning and Management (CALM) trial. Primary care patients who met study entry criteria (including DSM-IV diagnosis of generalized anxiety disorder, panic disorder, posttraumatic stress disorder, or social anxiety disorder) despite ongoing pharmacotherapy of appropriate type, dose, and duration were classified as medication resistant (n = 227). Logistic regression was used to estimate effects of CALM's CBT program (CALM-CBT; chosen by 104 of 117 medication-resistant patients randomized to CALM) versus usual care (UC; n = 110) on response [≥ 50% reduction of 12-item Brief Symptom Inventory (BSI-12) anxiety and somatic symptom score] and remission (BSI-12 < 6) at 6, 12, and 18 months. Within-group analyses examined outcomes by treatment choice (CBT vs. CBT plus medication management) and CBT dose. Approximately 58% of medication-resistant CALM-CBT patients responded and 46% remitted during the study. Relative to UC, CALM-CBT was associated with greater response at 6 months (AOR = 3.78, 95% CI 2.02-7.07) and 12 months (AOR = 2.49, 95% CI 1.36-4.58) and remission at 6, 12, and 18 months (AORs = 2.44 to 3.18). Patients in CBT plus medication management fared no better than those in CBT only. Some evidence suggested higher CBT dose produced better outcomes. CBT can improve outcomes for patients whose anxiety symptoms are resistant to standard pharmacotherapy. © 2016 Wiley Periodicals, Inc.

  6. Learn to Say Yes! When You Want to Say No! to Create Cooperation Instead of Resistance: Positive Behavior Strategies in Teaching

    ERIC Educational Resources Information Center

    Kersey, Katharine C.; Masterson, Marie L.

    2011-01-01

    It is human nature to be resistant when someone tells a person no. Children are no exception. Nevertheless, when teachers are frustrated with children's behavior, they may resort to saying no. Often the child responds, "Why?" or resists. What teachers really seek are strategies to help children in preschool and the early primary grades learn how…

  7. Learn to Say Yes! When You Want to Say No! to Create Cooperation Instead of Resistance: Positive Behavior Strategies in Teaching

    ERIC Educational Resources Information Center

    Kersey, Katharine C.; Masterson, Marie L.

    2011-01-01

    It is human nature to be resistant when someone tells a person no. Children are no exception. Nevertheless, when teachers are frustrated with children's behavior, they may resort to saying no. Often the child responds, "Why?" or resists. What teachers really seek are strategies to help children in preschool and the early primary grades learn how…

  8. Managing Resistance.

    ERIC Educational Resources Information Center

    Maag, John W.

    2000-01-01

    This article presents some considerations and ideas for managing students' resistance. They are organized around four topics: the impact of context on behavior, the importance of being comprehensive and nonrestrictive in behavior, the adaptive function of resistant behavior, and the benefit of joining children in their frame of reference.…

  9. Managing Resistance.

    ERIC Educational Resources Information Center

    Maag, John W.

    2000-01-01

    This article presents some considerations and ideas for managing students' resistance. They are organized around four topics: the impact of context on behavior, the importance of being comprehensive and nonrestrictive in behavior, the adaptive function of resistant behavior, and the benefit of joining children in their frame of reference.…

  10. Investigations of the hydrophobic and scratch resistance behavior of polystyrene films deposited on bell metal using RF-PACVD process

    NASA Astrophysics Data System (ADS)

    Choudhury, A. J.; Barve, S. A.; Chutia, Joyanti; Pal, A. R.; Chowdhury, D.; Kishore, R.; Jagannath; Mithal, N.; Pandey, M.; Patil, D. S.

    2011-02-01

    Polystyrene films are deposited on bell metal substrates using radiofrequency plasma assisted chemical vapor deposition (RF-PACVD) process. The deposition of polystyrene film is carried out at working pressure of 1.6 × 10-1 mbar and in the RF power range of 20-110 W. The hydrophobic and mechanical behaviors of the polystyrene films are studied as a function of RF power. The chemical compositions and surface chemistry of the polystyrene films are investigated using Raman spectroscopy and X-ray photoelectron spectroscopy (XPS). It is revealed that enhanced cross-linked chemical structure and higher loss of oxygen by peroxy polystyryl radical with increasing RF power results in the formation of polystyrene films with more hydrophobic and scratch resistance behavior. However, extensive destruction of cross-linked chemical structure due to high energetic ion bombardment tends to decrease the hydrophobic and scratch resistance behavior of the polystyrene film deposited at RF power of 110 W. Atomic force microscopy (AFM) images show quite uniform and crack free surfaces of the polystyrene films having rms roughness in the range of 0.35-0.87 nm. Attempts are made to correlate the characterization results with the parameters that are used for thin film depositions.

  11. Reduction-cleavable polymeric vesicles with efficient glutathione-mediated drug release behavior for reversing drug resistance.

    PubMed

    Ren, Tianbin; Wu, Wei; Jia, Menghong; Dong, Haiqing; Li, Yongyong; Ou, Zhouluo

    2013-11-13

    In the treatment of cancer, multidrug resistance (MDR) has been the major obstacle to the success of chemotherapy. The underlying mechanism relies on the overexpression of drug-efflux transporters that prevent the intracellular transport of the drug. In this study, reduction-cleavable vesicles were designed and developed with efficient glutathione-mediated drug-release behavior for reversing drug resistance. Polymeric vesicles were self-assembled from triblock copolymers with disulfide-bond-linked poly(ethylene glycol) (PEG) and poly(ε-benzyloxycarbonyl-L-lysine) (PzLL). Observations from transmission electron microscopy (TEM) and confocal laser scanning microscopy (CLSM) outline an obvious hollow structure surrounded by a thin outer layer, indicating the successful formation of the vesicles. Using fluorescently detectable doxorubicin hydrochloride (DOX·HCl) as the model drug, a significant acceleration of drug release regulated by glutathione (GSH) was found (>3-fold difference). Upon incubation of the DOX·HCl-loaded polymeric vesicles with the HeLa cervical cancer cell line exposed to glutathione, an enhanced nuclear accumulation of DOX·HCl was observed, elicited by the preferred disassembly of the vesicle structure under reducing conditions. Importantly, by using the gemcitabine hydrochloride (GC·HCl)-resistant breast cancer cell line MDA-MB-231, it was found that cell viability was significantly reduced after treatment with GC·HCl-loaded polymeric vesicles, indicating that these vesicles can help to reverse the drug resistance.

  12. Feeding behavior of Russian wheat aphid (Hemiptera: Aphididae) biotype 2 in response to wheat genotypes exhibiting antibiosis and tolerance resistance.

    PubMed

    Lazzari, Sonia; Starkey, Sharon; Reese, John; Ray-Chandler, Andrea; McCubrey, Raymond; Smith, C Michael

    2009-06-01

    In this study, wheat, Triticum aestivum L. (em Thell), genotypes containing the Dnx, Dn7, Dn6, and Dn4 genes for resistance to the Russian wheat aphid, Diuraphis noxia (Kurdjumov) (Hemiptera: Aphididae), along with Dn0, a susceptible control, were assessed to determine the categories of D. noxia biotype 2 (RWA2) resistance in each genotype and RWA2 feeding behaviors on Dnx and Dn0 plants by using the electronic penetration graph technique. At 14 d postinfestation, Dn0 plants exhibited intense chlorosis and leaf rolling, and all test genotypes expressed some degree of chlorosis and leaf rolling, except Dn7, which was not damaged. Both Dn7 and Dnx expressed antibiosis effects, significantly reducing the numbers of aphids on plants and the intrinsic rate of aphid increase. Dn6 plants seemed to contain tolerance, exhibiting tolerance index measurements for leaf and root dry weight and plant height that were significantly lower than those of the susceptible Dn0 plants. Principal component analyses indicated that antibiosis and leaf rolling data explained 80% of the variance among genotypes. Electronic penetration graph analysis demonstrated contrasting results between RWA1 and RWA2 phloem sieve element phase feeding events, but results indicated that Dnx resistance factors are present in the sieve element cells or phloem sap. Plants containing Dnx exhibit antibiosis resistance to D. noxia RWA2 similar to that in plants containing the Secale cereale L. (rye)-based Dn7 gene without the negative baking quality traits associated with Dn7.

  13. Adolescent self-regulation as resilience: resistance to antisocial behavior within the deviant peer context.

    PubMed

    Gardner, Theodore W; Dishion, Thomas J; Connell, Arin M

    2008-02-01

    This study tests the hypothesis that self-regulation serves as a resiliency factor in buffering youth from negative influences of peer deviance in middle to late adolescence. The interactive effects between peer deviance and self-regulation were investigated on change in antisocial behavior from age 17 to 19 years in an ethnically diverse sample of adolescents. A multi-agent construct was created using adolescent, parent, and teacher reports of self-regulation and peer deviance. Results indicated that self-regulation shows convergent validity and covaries as expected with developmental patterns of adolescent antisocial behavior. Self-regulation moderated the association of peer deviance with later self-reported adolescent antisocial behavior after controlling for prior levels of antisocial behavior. The implications of these findings for models for the development of antisocial behaviors and for intervention science are discussed.

  14. Impact of caregivers' behaviors on resistiveness to care and collaboration in persons with dementia in the context of hygienic care: an interactional perspective.

    PubMed

    Belzil, Guylaine; Vézina, Jean

    2015-11-01

    The role played by various physical and verbal behaviors of professional caregivers in the onset of resistiveness to care (RTC) and collaborative behaviors of nursing home residents with dementia was assessed in a daily hygienic care routine context. Two hundred and forty hygienic care routines, observed in eight nursing home residents, were analyzed with a video-assisted systematic observation methodology and a sequential statistical analysis strategy. Caregiver and care recipient behaviors are interdependent in the hygienic care routine context. Physical instrumental behavior, neutral, negative and positive statements, positive and negative instructions, and verbal distraction emitted by caregivers are significantly and moderately associated with the onset of RTC in persons with dementia (PWD), but the strength of relationships observed depends on the care recipient's behavior prior to the caregiver's action. Positive instructions are moderately associated with the onset of collaboration in residents with preserved language abilities. However, for residents with severe language impairment, these same instructions were linked to RTC behaviors. Although antecedents to RTC can be identified, the risk that caregiver behaviors trigger resistive responses is higher when care recipients are already exhibiting RTC, and is low when no particular behavior or collaboration is shown. Antecedents to collaboration are also identified and discussed. Although different caregiver behaviors may be more or less likely to elicit resistiveness or collaboration, it is the pre-existing state of the care recipient that will determine its reaction to the caregiver's behavior. Clinical implications emerging from these influential findings are elaborated.

  15. Impact of Treatments for Depression on Comorbid Anxiety, Attentional, and Behavioral Symptoms in Adolescents with Selective Serotonin Reuptake Inhibitor-Resistant Depression

    ERIC Educational Resources Information Center

    Hilton, Robert C.; Rengasamy, Manivel; Mansoor, Brandon; He, Jiayan; Mayes, Taryn; Emslie, Graham J.; Porta, Giovanna; Clarke, Greg N.; Wagner, Karen Dineen; Birmaher, Boris; Keller, Martin B.; Ryan, Neal; Shamseddeen, Wael; Asarnow, Joan Rosenbaum; Brent, David A.

    2013-01-01

    Objective: To assess the relative efficacy of antidepressant medication, alone and in combination with cognitive behavioral therapy (CBT), on comorbid symptoms of anxiety, attention, and disruptive behavior disorders in participants in the Treatment of Resistant Depression in Adolescents (TORDIA) trial. Method: Adolescents with selective serotonin…

  16. Impact of Treatments for Depression on Comorbid Anxiety, Attentional, and Behavioral Symptoms in Adolescents with Selective Serotonin Reuptake Inhibitor-Resistant Depression

    ERIC Educational Resources Information Center

    Hilton, Robert C.; Rengasamy, Manivel; Mansoor, Brandon; He, Jiayan; Mayes, Taryn; Emslie, Graham J.; Porta, Giovanna; Clarke, Greg N.; Wagner, Karen Dineen; Birmaher, Boris; Keller, Martin B.; Ryan, Neal; Shamseddeen, Wael; Asarnow, Joan Rosenbaum; Brent, David A.

    2013-01-01

    Objective: To assess the relative efficacy of antidepressant medication, alone and in combination with cognitive behavioral therapy (CBT), on comorbid symptoms of anxiety, attention, and disruptive behavior disorders in participants in the Treatment of Resistant Depression in Adolescents (TORDIA) trial. Method: Adolescents with selective serotonin…

  17. Negative differential resistance and switch behavior of T-BxNy (x, y = 5, 6, 11) molecular junctions

    NASA Astrophysics Data System (ADS)

    Wang, Shi-Liang; Yang, Chuan-Lu; Wang, Mei-Shan; Ma, Xiao-Guang; Xin, Jian-Guo

    2017-05-01

    The electronic transport properties of T-BxNy (x, y = 5, 6, 11) molecular junction are investigated based on first-principle density functional theory and non-equilibrium Green's function method. Strong negative differential resistance (NDR) behavior is observed for T-B5N6 molecule under negative and positive bias voltages, with an obvious switch effect for T-B6N5. However, only small NDR is shown for the complex of the two molecules. The projected device density of states, the spatial distribution of molecular orbitals, and the effect of transmission spectra under various bias voltages on the electronic transport properties are analyzed. The obvious effect of bias voltage on the changes in the electronic distribution of frontier molecular orbitals is responsible for the NDR or switch behavior. Therefore, different functional molecular devices can be obtained with different structures of T-BxNy.

  18. Hot Corrosion Resistance and Mechanical Behavior of Atmospheric Plasma Sprayed Conventional and Nanostructured Zirconia Coatings

    NASA Astrophysics Data System (ADS)

    Saremi, Mohsen; Keyvani, Ahmad; Heydarzadeh Sohi, Mahmoud

    Conventional and nanostructured zirconia coatings were deposited on In-738 Ni super alloy by atmospheric plasma spray technique. The hot corrosion resistance of the coatings was measured at 1050°C using an atmospheric electrical furnace and a fused mixture of vanadium pent oxide and sodium sulfate respectively. According to the experimental results nanostructured coatings showed a better hot corrosion resistance than conventional ones. The improved hot corrosion resistance could be explained by the change of structure to a dense and more packed structure in the nanocoating. The evaluation of mechanical properties by nano indentation method showed the hardness (H) and elastic modulus (E) of the YSZ coating increased substantially after hot corrosion.

  19. Corrosion resistance and antithrombogenic behavior of La and Nd ion implanted stainless steels

    SciTech Connect

    Jing, F. J.; Jin, F. Y.; Liu, Y. W.; Wan, G. J.; Liu, X. M.; Zhao, X. B.; Fu, R. K. Y.; Leng, Y. X.; Huang, N.; Chu, Paul K.

    2006-09-15

    Lanthanide ions such as lanthanum (La) and neodymium (Nd) were implanted into 316 stainless steel samples using metal vapor vacuum arc to improve the surface corrosion resistance and antithrombogenic properties. X-ray photoelectron spectroscopy shows that lanthanum and neodymium exist in the +3 oxidation state in the surface layer. The corrosion properties of the implanted and untreated control samples were investigated utilizing electrochemical tests and our results show that La and Nd implantations enhance the surface corrosion resistance. In vitro activated partial thromboplastin time (APTT) tests were used to evaluate the antithrombogenic properties. The APTT time of the implanted samples was observed to be prolonged compared to that of the unimplanted stainless steel control. La and Nd ion implantations can be used to improve the surface corrosion resistance and biomedical properties of 316 stainless steels.

  20. Intrinsic and interfacial effect of electrode metals on the resistive switching behaviors of zinc oxide films.

    PubMed

    Xue, W H; Xiao, W; Shang, J; Chen, X X; Zhu, X J; Pan, L; Tan, H W; Zhang, W B; Ji, Z H; Liu, G; Xu, X-H; Ding, J; Li, R-W

    2014-10-24

    Exploring the role of electrode metals on the resistive switching properties of metal electrode/oxide/metal electrode sandwiched structures provides not only essential information to understand the underlying switching mechanism of the devices, but also useful guidelines for the optimization of the switching performance. A systematic study has been performed to investigate the influence of electrodes on the resistive switching characteristics of zinc oxide (ZnO) films in this contribution, in terms of both the intrinsic and interfacial effects. It has been found that the low-resistance state resistances (Ω(LRS)) of all the investigated devices are below 50 Ω, which can be attributed to the formation of highly conductive channels throughout the ZnO films. On the other hand, the high-resistance state resistances (Ω(HRS)) depend on the electronegativity and ionic size of the employed electrode metals. Devices with electrode metals of high electronegativity and large ionic size possess high Ω(HRS) values, while those with electrode metals of low electronegativity and small ionic size carry low Ω(HRS) values. A similar trend of the set voltages has also been observed, while the reset voltages are all distributed in a narrow range close to ±0.5 V. Moreover, the forming voltages of the switching devices strongly depend on the roughness of the metal/ZnO and/or ZnO/metal interface. The present work provides essential information for better understanding the switching mechanism of zinc oxide based devices, and benefits the rational selection of proper electrode metals for the device performance optimization.

  1. Alcohol-Mediated Resistance-Switching Behavior in Metal-Organic Framework-Based Electronic Devices.

    PubMed

    Liu, Yaqing; Wang, Hong; Shi, Wenxiong; Zhang, Weina; Yu, Jiancan; Chandran, Bevita K; Cui, Chenlong; Zhu, Bowen; Liu, Zhiyuan; Li, Bin; Xu, Cai; Xu, Zhiling; Li, Shuzhou; Huang, Wei; Huo, Fengwei; Chen, Xiaodong

    2016-07-25

    Metal-organic frameworks (MOFs) have drawn increasing attentions as promising candidates for functional devices. Herein, we present MOF films in constructing memory devices with alcohol mediated resistance switching property, where the resistance state is controlled by applying alcohol vapors to achieve multilevel information storage. The ordered packing mode and the hydrogen bonding system of the guest molecules adsorbed in MOF crystals are shown to be the reason for the alcohol mediated electrical switching. This chemically mediated memory device can be a candidate in achieving environment-responsive devices and exhibits potential applications in wearable information storage systems. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Fault current limiter-predominantly resistive behavior of a BSCCO shielded-core reactor

    SciTech Connect

    Ennis, M. G.; Tobin, T. J.; Cha, Y. S.; Hull, J. R.

    2000-06-30

    Tests were conducted to determine the electrical and magnetic characteristics of a superconductor shielded core reactor (SSCR). The results show that a closed-core SSCR is predominantly a resistive device and an open-core SSCR is a hybrid resistive/inductive device. The open-core SSCR appears to dissipate less than the closed-core SSCR. However, the impedance of the open-core SSCR is less than that of the closed-core SSCR. Magnetic and thermal diffusion are believed to be the mechanism that facilitates the penetration of the superconductor tube under fault conditions.

  3. Bread wheat milling behavior: effects of genetic and environmental factors, and modeling using grain mechanical resistance traits.

    PubMed

    Oury, François-Xavier; Lasme, P; Michelet, C; Dubat, A; Gardet, O; Heumez, E; Rolland, B; Rousset, M; Abecassis, J; Bar L'Helgouac'h, C; Lullien-Pellerin, V

    2017-05-01

    Genetic (Pinb-D1 alleles) and environment (through vitreousness) have important effects on bread wheat milling behavior. SKCS optimal values corresponding to soft vitreous or hard mealy grains were defined to obtain the highest total flour yield. Near-isogenic lines of bread wheat that differ in hardness, due to distinct puroindoline-b alleles (the wild type, Pinb-D1a, or the mutated forms, Pinb-D1b or Pinb-D1d), were grown in different environments and under two nitrogen fertilization levels, to study genetic and environmental effects on milling behavior. Milling tests used a prototype mill, equipped with two break steps, one sizing step, and two reduction steps, and this enabled 21 individual or aggregated milling fractions to be collected. Four current grain characters, thousand grain weight, test weight, grain diameter, and protein content, were measured, and three characters known to influence grain mechanical resistance, NIRS hardness, SKCS hardness index, and grain vitreousness (a character affecting the grain mechanical behavior but generally not studied). As expected, the wild type or mutated forms of Pinb-D1 alleles led to contrasted milling behavior: soft genotypes produced high quantities of break flour and low quantities of reduction flour, whereas reverse quantities were observed for hard genotypes. This different milling behavior had only a moderate influence on total flour production. NIRS hardness and vitreousness were, respectively, the most important and the second most important grain characters to explain milling behavior. However, contrary to NIRS hardness, vitreousness was only involved in endosperm reduction and not in the separation between the starchy endosperm and the outer layers. The highest flour yields were obtained for SKCS values comprised between 30 and 50, which corresponded either to soft vitreous or hard mealy grains. Prediction equations were defined and showed a good accuracy estimating break and reduction flours portions, but

  4. Exaggerated acquisition and resistance to extinction of avoidance behavior in treated heroin-dependent men.

    PubMed

    Sheynin, Jony; Moustafa, Ahmed A; Beck, Kevin D; Servatius, Richard J; Casbolt, Peter A; Haber, Paul; Elsayed, Mahmoud; Hogarth, Lee; Myers, Catherine E

    2016-03-01

    Addiction is often conceptualized as a behavioral strategy for avoiding negative experiences. In rodents, opioid intake has been associated with abnormal acquisition and extinction of avoidance behavior. Here, we tested the hypothesis that these findings would generalize to human opioid-dependent subjects. Adults meeting DSM-IV criteria for heroin dependence and treated with opioid medication (n = 27) and healthy controls (n = 26) were recruited between March 2013 and October 2013 and given a computer-based task to assess avoidance behavior. For this task, subjects controlled a spaceship and could either gain points by shooting an enemy spaceship or hide in safe areas to avoid on-screen aversive events. Hiding duration during different periods of the task was used to measure avoidance behavior. While groups did not differ on escape responding (hiding) during the aversive event, heroin-dependent men (but not women) made more avoidance responses during a warning signal that predicted the aversive event (analysis of variance, sex × group interaction, P = .007). Heroin-dependent men were also slower to extinguish the avoidance response when the aversive event no longer followed the warning signal (P = .011). This behavioral pattern resulted in reduced opportunity to obtain reward without reducing risk of punishment. Results suggest that, in male patients, differences in avoidance behavior cannot be easily explained by impaired task performance or by exaggerated motor activity. This study provides evidence for abnormal acquisition and extinction of avoidance behavior in opioid-dependent patients. Interestingly, data suggest that abnormal avoidance is demonstrated only by male patients. Findings shed light on cognitive and behavioral manifestations of opioid addiction and may facilitate development of therapeutic approaches to help affected individuals. © Copyright 2016 Physicians Postgraduate Press, Inc.

  5. Quasi-static puncture resistance behaviors of high-strength polyester fabric for soft body armor

    NASA Astrophysics Data System (ADS)

    Wang, Qiu-Shi; Sun, Run-Jun; Tian, Xiao; Yao, Mu; Feng, Yan

    A series of economical and flexible fabrics were prepared using high-strength polyester yarns with different fabric structures, weft density and number of layers. The effect of these factors on quasi-static puncture resistance was comparatively studied. The failure mode of the fabrics was analyzed with SEM photographs. Findings indicate that the structure and the weft density affected the quasi-static puncture resistance property of the fabrics, the plain fabrics had better puncture resistance property than twill and satin fabrics. The max puncture force and puncture energy of the plain fabrics with 160 yarn/10 cm reached the max values which were 107.43 N and 0.44 J, respectively. The number of layers had a linear relationship to quasi-static puncture resistance. The contact pressure and friction of the probe against the fibers were the main hindrance during the quasi-static puncture process and the breakage of the fibers during the penetration was caused by the bend and tensile deformation.

  6. Individual Differences in Resistance-To-Temptation Behavior in Adolescents: An Eysenck Analysis

    ERIC Educational Resources Information Center

    La Voie, Joseph C.

    1973-01-01

    Contrary to Eysenck's predictions, neither introversion-extraversion nor level of anxiety, as measured on two separate scales, correlated significantly with the Resistance-to-Temptation measures, which suggests that conditionability in punishment is associated minimally with level of RTT. (Author)

  7. Learned Behavior: The Key to Understanding and Preventing Employee Resistance to Change

    ERIC Educational Resources Information Center

    Mealiea, Laird W.

    1978-01-01

    Develops a conceptual model that describes how and why employees learn to resist planned change within an organizational setting. Planned change, when introduced by management, has the potential of blocking affected employees from satisfying their dominant need structures. Change strategies are developed for management to reduce employee…

  8. Travel Destinations and Sexual Behavior as Indicators of Antibiotic Resistant Shigella Strains--Victoria, Australia.

    PubMed

    Lane, Courtney R; Sutton, Brett; Valcanis, Mary; Kirk, Martyn; Walker, Cathryn; Lalor, Karin; Stephens, Nicola

    2016-03-15

    Knowledge of relationships between antibiotic susceptibility of Shigella isolates and travel destination or other risk factors can assist clinicians in determining appropriate antibiotic therapy prior to susceptibility testing. We describe relationships between resistance patterns and risk factors for acquisition in Shigella isolates using routinely collected data for notified cases of shigellosis between 2008 and 2012 in Victoria, Australia. We included all shigellosis patients notified during the study period, where Shigella isolates were tested for antimicrobial sensitivity using Clinical and Laboratory Standards Institute breakpoints. Cases were interviewed to collect data on risk factors, including recent travel. Data were analyzed using Stata 13.1 to examine associations between risk factors and resistant strains. Of the 500 cases of shigellosis, 249 were associated with overseas travel and 210 were locally acquired. Forty-six of 51 isolates of Indian origin displayed decreased susceptibility or resistance to ciprofloxacin. All isolates of Indonesian origin were susceptible to ciprofloxacin. Twenty-six travel-related isolates were resistant to all tested oral antimicrobials. Male-to-male sexual contact was the primary risk factor for 80% (120/150) of locally acquired infections among adult males, characterized by distinct periodic Shigella sonnei outbreaks. Clinicians should consider travel destination as a marker for resistance to common antimicrobials in returning travelers, where severe disease requires empirical treatment prior to receipt of individual sensitivity testing results. Repeated outbreaks of locally acquired shigellosis among men who have sex with men highlight the importance of prevention and control measures in this high-risk group. © The Author 2015. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail journals.permissions@oup.com.

  9. Corrosion resistance and behavior of construction materials exposed to dilute sulfuric acid at elevated temperatures under static conditions

    SciTech Connect

    Nguyen, D.T.

    1994-10-01

    Laboratory investigation has been undertaken to determine the electrochemical behavior and corrosion resistance of various construction materials in a simulated hydrolysis environment (5 wt % sulfuric acid) at temperatures ranging from 90 to 220C. Tests were performed in an autoclave-type electrochemical cell. The corrosion behavior of the test materials was determined using computer-controlled DC potentiodynamic polarization. Corrosion rates of the test materials were determined using AC impedance techniques. Among the stainless steels tested, only alloy N08026 (Carpenter 20Mo-6) performed satisfactory up to a temperature of 100C. The alloy passivated spontaneously in the environment and corroded at a rate of less than 2 mpy. None of the stainless steels tested could be used at 120{degrees}C or above. A number of nickel-based alloys tested had good corrosion resistance up to 100C, but their corrosion rate exceeded 2 mpy at higher temperatures. Zirconium alloys were satisfactory up to 180C. Only tantalum and a tantalum-niobium alloy were satisfactory up to 220C.

  10. Abnormal Osmotic Avoidance Behavior in C. elegans Is Associated with Increased Hypertonic Stress Resistance and Improved Proteostasis

    PubMed Central

    Lee, Elaine C.; Kim, Heejung; Ditano, Jennifer; Manion, Dacie; King, Benjamin L.; Strange, Kevin

    2016-01-01

    Protein function is controlled by the cellular proteostasis network. Proteostasis is energetically costly and those costs must be balanced with the energy needs of other physiological functions. Hypertonic stress causes widespread protein damage in C. elegans. Suppression and management of protein damage is essential for optimal survival under hypertonic conditions. ASH chemosensory neurons allow C. elegans to detect and avoid strongly hypertonic environments. We demonstrate that mutations in osm-9 and osm-12 that disrupt ASH mediated hypertonic avoidance behavior or genetic ablation of ASH neurons are associated with enhanced survival during hypertonic stress. Improved survival is not due to altered systemic volume homeostasis or organic osmolyte accumulation. Instead, we find that osm-9(ok1677) mutant and osm-9(RNAi) worms exhibit reductions in hypertonicity induced protein damage in non-neuronal cells suggesting that enhanced proteostasis capacity may account for improved hypertonic stress resistance in worms with defects in osmotic avoidance behavior. RNA-seq analysis revealed that genes that play roles in managing protein damage are upregulated in osm-9(ok1677) worms. Our findings are consistent with a growing body of work demonstrating that intercellular communication between neuronal and non-neuronal cells plays a critical role in integrating cellular stress resistance with other organismal physiological demands and associated energy costs. PMID:27111894

  11. Adolescent alcohol exposure reduces behavioral flexibility, promotes disinhibition, and increases resistance to extinction of ethanol self-administration in adulthood.

    PubMed

    Gass, Justin T; Glen, William Bailey; McGonigal, Justin T; Trantham-Davidson, Heather; Lopez, Marcelo F; Randall, Patrick K; Yaxley, Richard; Floresco, Stan B; Chandler, L Judson

    2014-10-01

    The prefrontal cortex (PFC) is a brain region that is critically involved in cognitive function and inhibitory control of behavior, and adolescence represents an important period of continued PFC development that parallels the maturation of these functions. Evidence suggests that this period of continued development of the PFC may render it especially vulnerable to environmental insults that impact PFC function in adulthood. Experimentation with alcohol typically begins during adolescence when binge-like consumption of large quantities is common. In the present study, we investigated the effects of repeated cycles of adolescent intermittent ethanol (AIE) exposure (postnatal days 28-42) by vapor inhalation on different aspects of executive functioning in the adult rat. In an operant set-shifting task, AIE-exposed rats exhibited deficits in their ability to shift their response strategy when the rules of the task changed, indicating reduced behavioral flexibility. There were no differences in progressive ratio response for the reinforcer suggesting that AIE did not alter reinforcer motivation. Examination of performance on the elevated plus maze under conditions designed to minimize stress revealed that AIE exposure enhanced the number of entries into the open arms, which may reflect either reduced anxiety and/or disinhibition of exploratory-like behavior. In rats that trained to self-administer ethanol in an operant paradigm, AIE increased resistance to extinction of ethanol-seeking behavior. This resistance to extinction was reversed by positive allosteric modulation of mGluR5 during extinction training, an effect that is thought to reflect promotion of extinction learning mechanisms within the medial PFC. Consistent with this, CDPPB was also observed to reverse the deficits in behavioral flexibility. Finally, diffusion tensor imaging with multivariate analysis of 32 brain areas revealed that while there were no differences in the total brain volume, the volume of

  12. Exaggerated acquisition and resistance to extinction of avoidance behavior in treated heroin-dependent males

    PubMed Central

    Sheynin, Jony; Moustafa, Ahmed A.; Beck, Kevin D.; Servatius, Richard J.; Casbolt, Peter A.; Haber, Paul; Elsayed, Mahmoud; Hogarth, Lee; Myers, Catherine E.

    2015-01-01

    Objective Addiction is often conceptualized as a behavioral strategy for avoiding negative experiences. In rodents, opioid intake has been associated with abnormal acquisition and extinction of avoidance behavior. Here, we tested the hypothesis that these findings would generalize to human opioid-dependent subjects. Method Adults meeting DSM-IV criteria for heroin-dependence and treated with opioid medication (n=27), and healthy controls (n=26), were recruited between March–October 2013 and given a computer-based task to assess avoidance behavior. On this task, subjects controlled a spaceship and could either gain points by shooting an enemy spaceship, or hide in safe areas to avoid on-screen aversive events. Results While groups did not differ on escape responding (hiding) during the aversive event, heroin-dependent males (but not females) made more avoidance responses during a warning signal that predicted the aversive event (ANOVA, sex × group interaction, p=0.007). This group was also slower to extinguish the avoidance response when the aversive event no longer followed the warning signal (p=0.011). This behavioral pattern resulted in reduced opportunity to obtain reward without reducing risk of punishment. Results suggest that differences in avoidance behavior cannot be easily explained by impaired task performance or by exaggerated motor activity in male patients. Conclusion This study provides evidence for abnormal acquisition and extinction of avoidance behavior in opioid-dependent patients. Interestingly, data suggest abnormal avoidance is demonstrated only by male patients. Findings shed light on cognitive and behavioral manifestations of opioid addiction, and may facilitate development of therapeutic approaches to help affected individuals. PMID:27046310

  13. The role of oxygen vacancies in resistive switching behavior of organic-TiO2 hybrid composite

    NASA Astrophysics Data System (ADS)

    Zhang, Jiahua; Chen, Da; Huang, Shihua

    2017-10-01

    Effects of polyethylene glycol (PEG) on resistive switching behaviors and mechanisms in organic-TiO2 hybrid composites were investigated. The reversed current-voltage curves in the negative bias during the initial voltage sweeps were first observed in the composites annealed at 150, 200 and 250 °C, which is ascribed to the accumulation of oxygen vacancies and the inhibition effect of polarities of PEG chains. In addition, the volatility of composites with relatively high content of PEG is caused by the inhibition effect of PEG on creating oxygen vacancies. The formation and rupture of oxygen-vacancy filaments was considered as the resistive switching mechanism. Finally, the charging and discharging process in PEG-TiO2 composite annealed at 150 °C results in the instability of the electron-occupied oxygen vacancies and the inhibition of PEG chains. This study demonstrates a new way to investigate the interaction between polymers and TiO2 for understanding the resistive switching mechanism of TiO2-based memories.

  14. Wall slipping behavior of foam with nanoparticle-armored bubbles and its flow resistance factor in cracks.

    PubMed

    Lv, Qichao; Li, Zhaomin; Li, Binfei; Husein, Maen; Shi, Dashan; Zhang, Chao; Zhou, Tongke

    2017-07-11

    In this work, wall slipping behavior of foam with nanoparticle-armored bubbles was first studied in a capillary tube and the novel multiphase foam was characterized by a slipping law. A crack model with a cuboid geometry was then used to compare with the foam slipping results from the capillary tube and also to evaluate the flow resistance factor of the foam. The results showed that the slipping friction force F FR in the capillary tube significantly increased by addition of modified SiO2 nanoparticles, and an appropriate power law exponents by fitting F FR vs. Capillary number, Ca, was 1/2. The modified nanoparticles at the surface were bridged together and formed a dense particle "armor" surrounding the bubble, and the interconnected structures of the "armor" with strong steric integrity made the surface solid-like, which was in agreement with the slip regime associated with rigid surface. Moreover, as confirmed by 3D microscopy, the roughness of the bubble surface increased with nanoparticle concentration, which in turn increased the slipping friction force. Compared with pure SDBS foam, SDBS/SiO2 foam shows excellent stability and high flow resistance in visual crack. The resistance factor of SiO2/SDBS foam increased as the wall surface roughness increased in core cracks.

  15. Annealing behavior of Cu and dilute Cu-alloy films: Precipitation, grain growth, and resistivity

    NASA Astrophysics Data System (ADS)

    Barmak, K.; Gungor, A.; Cabral, C.; Harper, J. M. E.

    2003-08-01

    The impact of 11 alloying elements, namely, Mg, Ti, In, Sn, Al, Ag, Co, Nb, and B, at two nominal concentrations of 1 and 3 at. %, and Ir and W, at only a nominal concentration of 3 at. %, on the resistivity and grain structure of copper was investigated. The films were electron beam evaporated onto thermally oxidized Si wafers and had thicknesses in the range of 420-560 nm. Pure evaporated Cu films were used as controls. Isothermal anneals were carried out at 400 °C for 5 h; constant-heating rate treatments, with no hold at the temperature, were done at 3 °C to 650 and 950 °C. In all cases, annealing resulted in the lowering of resistivity compared with the as-deposited state. Furthermore, annealing to a higher temperature resulted in lower, postannealing, room-temperature resistivity, unless the film agglomerated or showed evidence of solute redissolution. Annealing also resulted in significant growth of grains, except for the Nb- and W-containing films. In addition, the grain sizes for the nominally 3 at. %, 400 °C-annealed films were smaller than those for the nominally 1.0 at. % films. The interesting exceptions in this case were the Co-containing films, which had a larger grain size than the pure Cu film, and which, in addition, exhibited a larger grain size for the film with the higher concentration of Co. After the 400 °C anneal, Cu(0.4B) and Cu(1.0Ag) had the lowest resistivities at 2.0 and 2.1 μΩ cm, respectively, and Cu(2.8Co) showed the largest average grain size at 1080 nm. The resistivity and grain size for the pure Cu film after the same anneal were 2.0 μΩ cm and 790 nm, respectively. Precipitation of a second phase was observed in 8 of 20 alloy films annealed at 400 °C. No alloy film simultaneously showed the combination of a low resistivity and a larger grain size than pure Cu.

  16. Selective Formation of a SnO2 Cap Layer, Its Growth Behavior, and Oxidation Resistance

    NASA Astrophysics Data System (ADS)

    Fujii, Yoshihito; Koike, Junichi; Sutou, Yuji; Li, Zifeng; Neishi, Koji

    2010-05-01

    In this paper, we propose a new method of cap-layer formation. The cap layer of SnO2 is formed by the displacement plating of Sn, followed by the oxidation of the plated Sn. An excellent plating selectivity was found between Cu and SiO2, but not with SiOCH. The SnO2 layer of 90 nm thickness showed a good oxidation resistance of the underlying Cu after heat treatment at 480 °C in air (PO2=105 Pa). In contrast, the SnO2 layers of 6 and 9 nm thickness showed oxidation resistance at 400 °C in Ar+10 ppm O2 (PO2=1 Pa), but not in Ar+1000 ppm O2 (PO2=100 Pa).

  17. Competing mechanisms in the wear resistance behavior of biomineralized rod-like microstructures

    NASA Astrophysics Data System (ADS)

    Escobar de Obaldia, Enrique; Herrera, Steven; Grunenfelder, Lessa Kay; Kisailus, David; Zavattieri, Pablo

    2016-11-01

    The remarkable mechanical properties observed in biological composite materials relative to those of their individual constituents distinguish them from common engineering materials. Some naturally occurring high-performance ceramics, like the external veneer of the Chiton (Cryptochiton stelleri) tooth, have been shown to have superior hardness and impressive abrasion resistance properties. The mechanical performance of the chiton tooth has been attributed to a hierarchical arrangement of nanostructured magnetite rods surrounded with organic material. While nanoindentation tests provide useful information about the overall performance of this biological composite, understanding the key microstructural features and energy dissipation mechanisms at small scales remains a challenging task. We present a combined experimental/numerical approach to elucidate the role of material deformation in the rods, debonding at the rod interfaces and the influence of energy dissipation mechanisms on the ability of the microstructure to distribute damage under extreme loading conditions. We employ a 3D finite element-based micromechanical model to simulate the nanoindentation tests performed in geological magnetite and cross-sections of the chiton tooth. This proposed model is capable of capturing the inelastic deformation of the rods and the failure of their interfaces, while damage, fracture and fragmentation of the mineralized rods is assessed using a probabilistic function. Our results show that these natural materials achieve their abrasion resistant properties by controlling the interface strength between rods, alleviating the tensile stress on the rods near the indentation tip and therefore decreasing the probability of catastrophic failure without significantly sacrificing resistance to penetration. The understanding of these competing energy dissipating mechanisms provides a path to the prediction of new combination of materials. In turns, these results suggest certain

  18. Age-related changes in pumping mechanical behavior of rat ventricle in terms of systolic elastance and resistance.

    PubMed

    Chang, K C; Peng, Y I; Dai, S H; Tseng, Y Z

    2000-09-01

    Both the maximal systolic elastance (Emax) and the theoretical maximal flow (Qmax) can quantify the systolic mechanical behavior of the ventricular pump. Physically, Emax can reflect the intrinsic contractility of the myocardium as an intact heart. The quantity in (Qmax is inversely related to the internal resistance of the left ventricle. How great the effects of age are on these Emax and Qmax has never been examined, however. This study was to determine the ventricular pumping mechanics in terms of the systolic elastance and resistance in male Fischer rats at 6, 12, 18, and 24 months of age. We measured left ventricular (LV) pressure and ascending aortic flow waves using a high-fidelity pressure sensor and an electromagnetic flow probe, respectively. Those two parameters that characterize the systolic pumping mechanics of the left ventricle are obtained by making use of an elastance-resistance model. The basic hemodynamic condition in those animals with different ages is characterized by (i) no significant change in cardiac output and (ii) a decrease in basal heart rate, LV end-systolic pressure, as well as effective arterial volume elastance. Changes that take place in the left ventricle with age include a decline in Emax and an increase in Qmax especially at 24 months. These results demonstrate that the impaired intrinsic contractility of an aging heart may be compensated to some extent by the diminished ventricular internal resistance. Such compensation in aging rats may maintain normal blood flow essential for the metabolic needs of tissues and/or organs before heart dysfunction and failure occur.

  19. Pedagogical Formation Students' Resistance Behaviors towards Teaching-Learning Processes and Their Moral Maturity

    ERIC Educational Resources Information Center

    Argon, Türkan; Sezen-Gültekin, Gözde

    2016-01-01

    Moral maturity, defined as the competence in moral emotions, thoughts, judgments, attitudes and behaviors, is one of the most important qualities that the would-be teachers at Faculties of Education must possess. Teachers with moral maturity will train students with the qualities of reliability, responsibility, fairness, objectivity, consistency…

  20. Adolescent Self-Regulation as Resilience: Resistance to Antisocial Behavior within the Deviant Peer Context

    ERIC Educational Resources Information Center

    Gardner, Theodore W.; Dishion, Thomas J.; Connell, Arin M.

    2008-01-01

    This study tests the hypothesis that self-regulation serves as a resiliency factor in buffering youth from negative influences of peer deviance in middle to late adolescence. The interactive effects between peer deviance and self-regulation were investigated on change in antisocial behavior from age 17 to 19 years in an ethnically diverse sample…

  1. Adolescent Self-Regulation as Resilience: Resistance to Antisocial Behavior within the Deviant Peer Context

    ERIC Educational Resources Information Center

    Gardner, Theodore W.; Dishion, Thomas J.; Connell, Arin M.

    2008-01-01

    This study tests the hypothesis that self-regulation serves as a resiliency factor in buffering youth from negative influences of peer deviance in middle to late adolescence. The interactive effects between peer deviance and self-regulation were investigated on change in antisocial behavior from age 17 to 19 years in an ethnically diverse sample…

  2. Improving the seismic torsional behavior of plan-asymmetric, single-storey, concrete moment resisting buildings with fluid viscous dampers

    NASA Astrophysics Data System (ADS)

    Rofooei, Fayaz Rahimzadeh; Mohammadzadeh, Sahar

    2016-03-01

    The optimal distribution of fluid viscous dampers (FVD) in controlling the seismic response of eccentric, single-storey, moment resisting concrete structures is investigated using the previously defined center of damping constant (CDC). For this purpose, a number of structural models with different one-way stiffness and strength eccentricities are considered. Extensive nonlinear time history analyses are carried out for various arrangements of FVDs. It is shown that the arrangement of FVDs for controlling the torsional behavior due to asymmetry in the concrete structures is very dependent on the intensity of the peak ground acceleration (PGA) and the extent of the structural stiffness and strength eccentricities. The results indicate that, in the linear range of structural behavior the stiffness eccentricity es which is the main parameter in determining the location of optimal CDC, is found to be less or smaller than the optimal damping constant eccentricity e*d, i.e., |e*d| > |es|. But, in the nonlinear range of structural behavior where the strength eccentricity er is the dominant factor in determining the location of optimal CDC, |e*d| > |er|. It is also concluded that for the majority of the plan-asymmetric, concrete structures considered in this study with er ≠ 0, the optimal CDC approaches the center of mass as er decreases.

  3. Entering Adolescence: Resistance to Peer Influence, Risky Behavior, and Neural Changes in Emotion Reactivity

    PubMed Central

    Pfeifer, Jennifer H.; Masten, Carrie L.; Moore, William E.; Oswald, Tasha M.; Mazziotta, John C.; Iacoboni, Marco; Dapretto, Mirella

    2013-01-01

    SUMMARY Adolescence is often described as a period of heightened reactivity to emotions paired with reduced regulatory capacities, a combination suggested to contribute to risk-taking and susceptibility to peer influence during puberty. However, no longitudinal research has definitively linked these behavioral changes to underlying neural development. Here, 38 neurotypical participants underwent two fMRI sessions across the transition from late childhood (10 years) to early adolescence (13 years). Responses to affective facial displays exhibited a combination of general and emotion-specific changes in ventral striatum (VS), ventromedial PFC, amygdala, and temporal pole. Furthermore, VS activity increases correlated with decreases in susceptibility to peer influence and risky behavior. VS and amygdala responses were also significantly more negatively coupled in early adolescence than in late childhood while processing sad and happy versus neutral faces. Together, these results suggest that VS responses to viewing emotions may play a regulatory role that is critical to adolescent interpersonal functioning. PMID:21382560

  4. Risk-taking plants: anisohydric behavior as a stress-resistance trait.

    PubMed

    Sade, Nir; Gebremedhin, Alem; Moshelion, Menachem

    2012-07-01

    Water scarcity is a critical limitation for agricultural systems. Two different water management strategies have evolved in plants: an isohydric strategy and an anisohydric strategy. Isohydric plants maintain a constant midday leaf water potential (Ψleaf) when water is abundant, as well as under drought conditions, by reducing stomatal conductance as necessary to limit transpiration. Anisohydric plants have more variable Ψleaf and keep their stomata open and photosynthetic rates high for longer periods, even in the presence of decreasing leaf water potential. This risk-taking behavior of anisohydric plants might be beneficial when water is abundant, as well as under moderately stressful conditions. However, under conditions of intense drought, this behavior might endanger the plant. We will discuss the advantages and disadvantages of these two water-usage strategies and their effects on the plant's ability to tolerate abiotic and biotic stress. The involvement of plant tonoplast AQPs in this process will also be discussed.

  5. Boron(III)-Containing Donor-Acceptor Compound with Goldlike Reflective Behavior for Organic Resistive Memory Devices.

    PubMed

    Poon, Chun-Ting; Wu, Di; Yam, Vivian Wing-Wah

    2016-03-07

    A small-molecule-based boron(III)-containing donor-acceptor compound has been designed and synthesized. Interesting goldlike reflective behavior was observed in the neat thin-film sample from simple spin-coating preparation, which can serve as a potential organic thin-film optical reflector. The small thickness in nanometer range and the relatively smooth surface morphology, together with simple preparation and easy solution processability, are attractive features for opening up new avenues for the fabrication of reflective coatings. Moreover, this donor-acceptor compound has been employed in the fabrication of organic resistive memory device, which exhibited good performance with low turn-on voltage, small operating bias, large ON/OFF ratio, and long retention time. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Modified Cognitive Behavior Therapy for Severe, Treatment-Resistant Obsessive-Compulsive Disorder in an Adolescent With Autism Spectrum Disorder.

    PubMed

    Krebs, Georgina; Murray, Kim; Jassi, Amita

    2016-11-01

    There is a high rate of comorbidity between obsessive-compulsive disorder (OCD) and autism spectrum disorders (ASD). Standard cognitive-behavior therapy (CBT) protocols have been shown to be less effective in treating OCD in young people with ASD than in typically developing youth. This case study describes the treatment of an adolescent boy with severe, treatment-resistant OCD and ASD using a modified CBT approach. Modifications to a standard evidence-based CBT for OCD protocol included extended psychoeducation about anxiety; regular home-based sessions; and increased involvement of systems, including family and school. Multi-informant outcome data indicated significant improvements in OCD symptoms over the course of treatment with gains being maintained over a 12-month follow-up period. These findings demonstrate the potential efficacy of modified CBT for pediatric OCD in the context of ASD. © 2016 Wiley Periodicals, Inc.

  7. Challenges for malaria vector control in sub-Saharan Africa: Resistance and behavioral adaptations in Anopheles populations.

    PubMed

    Sougoufara, Seynabou; Doucouré, Souleymane; Backé Sembéne, Pape M; Harry, Myriam; Sokhna, Cheikh

    2017-01-01

    Over the past decade, global malaria-related mortality has declined dramatically because of combined international actions that have defined and prioritized national and regional efforts to reduce the incidence of malaria, with the ultimate goal of eradication. Vector control strategies using insecticide-treated nets (ITNs) and indoor residual spraying (IRS) in African countries have contributed significantly to the declining incidence of malaria. However, the effectiveness of malaria control is threatened by increasing insecticide resistance and behavioral changes in Anopheles vectors. Thus, there is an urgent need to ensure that future programmes are designed to address these threats and protect the progress made so far in controlling malaria. This review summarizes the current malaria vector control tools and discusses about the critical threats to vector control programme and vector management.

  8. In-situ observation of self-regulated switching behavior in WO{sub 3-x} based resistive switching devices

    SciTech Connect

    Hong, D. S.; Wang, W. X.; Chen, Y. S. Sun, J. R.; Shen, B. G.

    2014-09-15

    The transmittance of tungsten oxides can be adjusted by oxygen vacancy (V{sub o}) concentration due to its electrochromic property. Here, we report an in-situ observation of resistive switching phenomenon in the oxygen-deficient WO{sub 3-x} planar devices. Besides directly identifying the formation/rupture of dark-colored conductive filaments in oxide layer, the stripe-like WO{sub 3-x} device demonstrated self-regulated switching behavior during the endurance testing, resulting in highly consistent switching parameters after a stabilizing process. For very high V{sub o}s mobility was demonstrated in the WO{sub 3-x} film by the pulse experiment, we suggested that the electric-field-induced homogeneous migration of V{sub o}s was the physical origin for such unique switching characteristics.

  9. Mutant Plasmodium falciparum chloroquine resistance transporter in Hodeidah, Yemen: association with parasitologic indices and treatment-seeking behaviors.

    PubMed

    Abdul-Ghani, Rashad; Farag, Hoda F; Allam, Amal F; Shawky, Sherine M; Al-Mekhlafi, Abdulsalam M

    2013-12-01

    Malaria still represents a major health problem in Yemen, particularly in Hodeidah, despite continuing efforts to eliminate it. With the absence of clinically proven vaccines, chemotherapy with antimalarials is still greatly needed. Chloroquine (CQ) has been popular as the drug of choice for malaria control. However, Plasmodium falciparum resistance to CQ has been one of the main obstacles in malaria control and elimination. Although CQ is no longer the recommended antimalarial chemotherapy, it has remained the number one over-the-counter antimalarial drug in many endemic areas, including Yemen, and is still used for self-medication. In addition, promising reports on CQ efficacy reversal in many African countries brought it again into the scene. This has led to a growing interest in the possibility of its re-introduction, particularly with the concerns raised about the parasite resistance to artemisinin-based combination therapies. Therefore, the present study aimed at analyzing the CQ-associated pfcrt 76T mutation in P. falciparum isolates from patients with uncomplicated falciparum malaria in Hodeidah, west of Yemen. The association of treatment-seeking behaviors and antimalarial drug use with the pfcrt 76T mutant allele was also studied. It was revealed that there is still a sustained high frequency of this molecular marker among parasite isolates associated with younger age, decreased parasite density and the presence of gametocytes in blood. Delay in seeking treatment and frequent use of antimalarials were the behaviors significantly associated with the presence of the pfcrt 76T mutant allele among patients reporting a history of malaria treatment. Copyright © 2013 Elsevier B.V. All rights reserved.

  10. Analysis of corrosion resistance behavior of inhibitors in concrete using electrochemical techniques

    NASA Astrophysics Data System (ADS)

    Song, Ha-Won; Saraswathy, Velu

    2006-08-01

    Reinforced concrete is one of the most durable and cost effective construction materials. However, in high chloride environments, it can suffer from corrosion due to chloride induced breakdown of the normal passive layer protecting the reinforcing steel bars inside concrete. One means of protecting embedded steel reinforcement from chloride induced corrosion is the addition of corrosion inhibiting admixtures. In the present investigation, various inhibitors such as sodium nitrite, zinc oxide, mono ethanol amine, diethanolamine, and triethanol amine have been used in concrete in different percentages. Their effectiveness was then studied using various electrochemical techniques such as rapid chloride ion penetration test, open circuit potential measurement, electrochemical impedance measurement, potentiodynamic polarization measurement, and gravimetric weight loss measurement. The results thus obtained indicate that the addition of inhibitors enhances the corrosion resistance properties.

  11. Dependence of Precipitation Behavior and Creep Strength on Cr Content in High Cr Ferritic Heat Resistant Steels

    NASA Astrophysics Data System (ADS)

    Murata, Yoshinori; Yamashita, Koji; Morinaga, Masahiko; Hara, Toru; Miki, Kazuhiro; Azuma, Tsukasa; Ishiguro, Toru; Hashizume, Ryokichi

    It is known that high temperature tensile strength increases with increasing Cr content in Cr containing heat resistant steels. Recently, however, it was found that long-term creep strength decreased with increasing Cr content in the heat resistant steels containing 8.5-12%Cr. In this study, precipitation behavior of M23C6 carbide and the Z phase after creep tests was investigated using two kinds of high Cr ferritic steels (9Cr and 10.5Cr). As a result, 10.5Cr steel exhibited larger average particle size of M23C6 than 9Cr steel irrespective of creep stress levels, but the amount of M23C6 carbide was almost the same in both steels. On the other hand, the amount of the Z phase became large in 10.5Cr steel compared with 9Cr steel. These experimental results indicate that high level of Cr content accelerates precipitation and coalescence rate of both M23C6 carbide and the Z phase, resulting in degradation of long term creep strength in 10.5 Cr steel compared to 9Cr steel.

  12. Behavior of an improved Zr fuel cladding with oxidation resistant coating under loss-of-coolant accident conditions

    NASA Astrophysics Data System (ADS)

    Park, Dong Jun; Kim, Hyun Gil; Jung, Yang Il; Park, Jung Hwan; Yang, Jae Ho; Koo, Yang Hyun

    2016-12-01

    This study investigates protective coatings for improving the high temperature oxidation resistance of Zr fuel claddings for light water nuclear reactors. FeCrAl alloy and Cr layers were deposited onto Zr plates and tubes using cold spraying. For the FeCrAl/Zr system, a Mo layer was introduced between the FeCrAl coating and the Zr matrix to prevent inter-diffusion at high temperatures. Both the FeCrAl and Cr coatings improved the oxidation resistance compared to that of the uncoated Zr alloy when exposed to a steam environment at 1200 °C. The ballooning behavior and mechanical properties of the coated cladding samples were studied under simulated loss-of-coolant accident conditions. The coated samples showed higher burst temperatures, lower circumferential strain, and smaller rupture openings compared to the uncoated Zr. Although 4-point bend tests of the coated samples showed a small increase in the maximum load, ring compression tests of a sectioned sample showed increased ductility.

  13. Enhanced superconductivity, Kondo behavior, and negative-curvature resistivity of oxygen-irradiated thin films of aluminium

    NASA Astrophysics Data System (ADS)

    Sinnecker, E. H. C. P.; Sant'Anna, M. M.; ElMassalami, M.

    2017-02-01

    We followed the evolution of the normal and superconducting properties of Al thin films after each session of various successive oxygen irradiations at ambient temperature. Such irradiated films, similar to the granular ones, exhibit enhanced superconductivity, Kondo behavior, and negative-curvature resistivity. Two distinct roles of oxygen are identified: as a damage-causing projectile and as an implanted oxidizing agent. The former gives rise to the processes involved in the conventional recovery stages. The latter, considered within the context of the Cabrera-Mott model, gives rise to a multistep process which involves charges transfer and creation of stabilized vacancies and charged defects. Based on the outcome of this multistep process, we consider (i) the negative-curvature resistivity as a manifestation of a thermally assisted liberation of trapped electric charges, (ii) the Kondo contribution as a spin-flip scattering from paramagnetic, color-center-type defects, and (iii) the enhancement of Tc as being due to a lattice softening facilitated by the stabilized defects and vacancies. The similarity in the phase diagrams of granular and irradiated films as well as the aging effects are discussed along the same line of reasoning.

  14. [Courtship behavior, communicative sound production and resistance to stress in Drosophila mutants with defective agnostic gene, coding for LIMK1].

    PubMed

    Popov, A V; Kaminskaia, A N; Savvateeva-Popova, E V

    2009-01-01

    To elucidate the role of one of the main elements of signal cascade of actin remodeling--LIM-kinase 1 (LIMK1)--in the control of animal behavior we studied the characteristics of courtship behavior, parameters of acoustic communicative signals and their resistance to heat shock (HS, 37 degrees C, 30 min) in Drosophila melanogaster males from the strain with mutation in locus agnostic (agn(ts3)) containing gene CG1848 for LIMK1. The data obtained was compared with the results of our previous similar investigation on wild type CS males (Popov et al., 2006). Flies were divided into 4 groups. The males of control groups were not subjected to heat shock. The rest of males were subjected to heat shock either at the beginning of larval development when predominantly mushroom body neuroblasts are dividing (groups HS1), or at the prepupal stage when the brain central complex is developing (groups HS2), or at the imago stage one hour before the test (groups HS3). All males were tested at the age of 5 days. Virgin and fertilized CS females were used as courtship objects. Comparison of control groups of the two strains--CS and agnostic--have shown that the mutation agn(ts3) has no influence on the main parameters of courtship behavior of intact (not subjected to HS) males (courtship latency, the rapidity of achieving copulation, courtship efficiency) but leads to lowering of their sexual activity, increase of duration of sound trains in the songs and to slight increase of rate and stability of working of singing pacemakers. Agnostic males in comparison to wild type males are more resistant to HS given 1 hour before the test. After HS their courtship intensity does not decrease and the main parameters of their courtship behavior and communicative sound signals in comparison tu wild type males either do not change, or appear to be even better stabilized. The frequency of distorted sound pulses (an indicator of frequency of impairments in the activity pattern of neuro

  15. Elevated temperature annealing behaviors of bulk resistivity and space charge density (Neff) of neutron irradiated silicon detectors and materials

    NASA Astrophysics Data System (ADS)

    Z., Li

    1996-02-01

    The bulk resistivity of neutron irradiated detector grade silicon material has been measured under the condition of no or low electrical filed (electrical neutral bulk or ENB condition) after elevated temperature (T = 110°C) anneals (ETA). The ENB resistivity (ρ) for as-irradiated silicon material increases with neutron fluence at low fluences (Φn > 1013 n/cm2). The saturation of the ENB resistivity near the intrinsic value can be explained by the near perfect compensation of all neutron induced deep donors and acceptors in the ENB. After ETA, it has been observed that ρ increases with annealing time for silicon materials irradiated below the saturation and decreases with annealing time for those irradiated after saturation. For those irradiated near the saturation point, ρ increases with annealing time initially and decreases thereafter. This ETA behavior of ρ may be explained by the increase of net acceptor-like deep levels in silicon during the anneal, qualitatively consistent with the observed reverse annealing effect of the space charge density (Neff) in silicon detectors which is an increase of negative space charge density (acceptors) after long term room temperature (RTA) anneal and/or ETA. However, the amount of the increase of net hole concentration (p) of about 5 × 1011 cm-3, corresponding to 20 hours of ETA at 110°C for a fluence of 1.5 × 1014 n/cm2, is still much less than the corresponding increase of Neff of about 1.5 × 1013 cm-3. This suggests that while the ETA restores some of the free carrier concentration (namely holes), there is still a large degree of compensation. The space charge density is still dominated by the deep levels and Neff ≠ p.

  16. Radiation degradation behavior of chlorine-containing vinyl copolymers. Search for improved electron-beam resists

    SciTech Connect

    Helbert, J.N.; Poindexter, E.H.; Pittman, C.U. Jr.; Chen, C.Y.

    1980-06-01

    Vinyl copolymers with high radiation degradation sensitivity have been synthesized by copolymerizing vinylidene chloride (VDC), CH/sub 2/ = CCl/sub 2/, with methyl methacrylate (MMA), methacrylonitrile, methyl ..cap alpha..-chloroacrylate, and dimethyl itaconate using emulsion techniques. In addition, copolymers of methyl ..cap alpha..-chloroacrylate with methyl methacrylate and poly(..cap alpha..-chloroacrylonitrile) were studied. Introduction of vinylidene chloride into methyl methacrylate polymers caused a sharp increase in G/sub s/ even at relatively low VDC incorporation. Upon 29% VDC incorporation, the G/sub s/ value increased from 1.3 (homopolymer of MMA) to 3.4. G/sub s/ was found to be a linear function of copolymer content for several systems, but G/sub x/ was not. At higher VDC levels, the increase in G/sub s/ was countered by increases in G/sub x/. At lower VDC levels, G/sub x/ was suppressed below the values predicted by a linear G/sub x/ dependence on composition for such systems as VDC/MMA, MCA/MMA, and ..cap alpha..-chloroacrylonitrile/MMA. The VDC/MMA copolymer (29% VDC) gave a sensitivity of 4.0 x 10/sup -5/ C/cm/sup 2/ to electron beam exposure using the 0% unexposed resist thickness loss criterion and is 2 to 3 times more sensitive than PMMA. Poly(..cap alpha..-chloroacrylonitrile) is a negative resist with a sensitivity of 5 x 10/sup -5/ C/cm/sup 2/ using one-micron line images for testing.

  17. Light and magnetic field double modulation on the resistive switching behavior in BaTiO3/FeMn/BaTiO3 trilayer films

    NASA Astrophysics Data System (ADS)

    Li, Hongwei; Wu, Shuxiang; Hu, Ping; Li, Dan; Wang, Gaili; Li, Shuwei

    2017-07-01

    An obvious resistive switching (RS) was observed in BaTiO3/FeMn/BaTiO3 (BFB) trilayer films under different conditions. The RS effect was enhanced in light irradiation and restrained in magnetic field. The ratio of high resistance to low resistance of samples annealed at 500 °C is larger than 1500, and the samples showed a good stability. SET and RESET voltages decrease with increasing illumination intensity, but the ON/OFF ratio showed an inverse tendency. Conduction mechanisms in low resistance and high resistance were determined to be Ohmic and space charge limited conduction (SCLC) mechanism, respectively. A redistribution of oxygen vacancies and bound magnetic polaron (BMP) were used for explanation of the mechanism of RS behavior in this system under light irradiation and magnetic field, respectively.

  18. A Physiological and Behavioral Mechanism for Leaf Herbivore-Induced Systemic Root Resistance.

    PubMed

    Erb, Matthias; Robert, Christelle A M; Marti, Guillaume; Lu, Jing; Doyen, Gwladys R; Villard, Neil; Barrière, Yves; French, B Wade; Wolfender, Jean-Luc; Turlings, Ted C J; Gershenzon, Jonathan

    2015-12-01

    Indirect plant-mediated interactions between herbivores are important drivers of community composition in terrestrial ecosystems. Among the most striking examples are the strong indirect interactions between spatially separated leaf- and root-feeding insects sharing a host plant. Although leaf feeders generally reduce the performance of root herbivores, little is known about the underlying systemic changes in root physiology and the associated behavioral responses of the root feeders. We investigated the consequences of maize (Zea mays) leaf infestation by Spodoptera littoralis caterpillars for the root-feeding larvae of the beetle Diabrotica virgifera virgifera, a major pest of maize. D. virgifera strongly avoided leaf-infested plants by recognizing systemic changes in soluble root components. The avoidance response occurred within 12 h and was induced by real and mimicked herbivory, but not wounding alone. Roots of leaf-infested plants showed altered patterns in soluble free and soluble conjugated phenolic acids. Biochemical inhibition and genetic manipulation of phenolic acid biosynthesis led to a complete disappearance of the avoidance response of D. virgifera. Furthermore, bioactivity-guided fractionation revealed a direct link between the avoidance response of D. virgifera and changes in soluble conjugated phenolic acids in the roots of leaf-attacked plants. Our study provides a physiological mechanism for a behavioral pattern that explains the negative effect of leaf attack on a root-feeding insect. Furthermore, it opens up the possibility to control D. virgifera in the field by genetically mimicking leaf herbivore-induced changes in root phenylpropanoid patterns.

  19. Cold resistance depends on acclimation and behavioral caste in a temperate ant

    NASA Astrophysics Data System (ADS)

    Modlmeier, Andreas P.; Pamminger, Tobias; Foitzik, Susanne; Scharf, Inon

    2012-10-01

    Adjusting to low temperatures is important for animals living in cold environments. We studied the chill-coma recovery time in temperate ant workers ( Temnothorax nylanderi) from colonies collected in autumn and spring in Germany. We experimentally acclimated these ant colonies to cold temperatures followed by warm temperatures. As expected, cold-acclimated workers recovered faster from freezing temperatures, but subsequent heat acclimation did not change the short recovery times observed after cold acclimation. Hence, either heat acclimation improves cold tolerance, possibly as a general response to stress, or at least it does not negate enhanced cold tolerance following cold acclimation. Colonies collected in spring showed similar cold tolerance levels to cold-acclimated colonies in the laboratory. Next, we compared the chill-coma recovery time of different worker castes and found that exterior workers recovered faster than interior workers. This difference may be related to their more frequent exposure to cold, higher activity level, or distinct physiology. Interior workers were also heavier and showed a higher gaster-to-head ratio and thorax ratio compared to exterior workers. An obvious difference between exterior and interior workers is activity level, but we found no link between activity and cold tolerance. This suggests that physiology rather than behavioral differences could cause the increased cold tolerance of exterior workers. Our study reveals the importance of acclimation for cold tolerance under natural and standardized conditions and demonstrates differences in cold tolerance and body dimensions in monomorphic behavioral castes of an ant.

  20. Entering adolescence: resistance to peer influence, risky behavior, and neural changes in emotion reactivity.

    PubMed

    Pfeifer, Jennifer H; Masten, Carrie L; Moore, William E; Oswald, Tasha M; Mazziotta, John C; Iacoboni, Marco; Dapretto, Mirella

    2011-03-10

    Adolescence is often described as a period of heightened reactivity to emotions paired with reduced regulatory capacities, a combination suggested to contribute to risk-taking and susceptibility to peer influence during puberty. However, no longitudinal research has definitively linked these behavioral changes to underlying neural development. Here, 38 neurotypical participants underwent two fMRI sessions across the transition from late childhood (10 years) to early adolescence (13 years). Responses to affective facial displays exhibited a combination of general and emotion-specific changes in ventral striatum (VS), ventromedial PFC, amygdala, and temporal pole. Furthermore, VS activity increases correlated with decreases in susceptibility to peer influence and risky behavior. VS and amygdala responses were also significantly more negatively coupled in early adolescence than in late childhood while processing sad and happy versus neutral faces. Together, these results suggest that VS responses to viewing emotions may play a regulatory role that is critical to adolescent interpersonal functioning. Copyright © 2011 Elsevier Inc. All rights reserved.

  1. A Physiological and Behavioral Mechanism for Leaf Herbivore-Induced Systemic Root Resistance1[OPEN

    PubMed Central

    Erb, Matthias; Robert, Christelle A.M.; Marti, Guillaume; Lu, Jing; Doyen, Gwladys R.; Villard, Neil; Barrière, Yves; Wolfender, Jean-Luc; Turlings, Ted C.J.

    2015-01-01

    Indirect plant-mediated interactions between herbivores are important drivers of community composition in terrestrial ecosystems. Among the most striking examples are the strong indirect interactions between spatially separated leaf- and root-feeding insects sharing a host plant. Although leaf feeders generally reduce the performance of root herbivores, little is known about the underlying systemic changes in root physiology and the associated behavioral responses of the root feeders. We investigated the consequences of maize (Zea mays) leaf infestation by Spodoptera littoralis caterpillars for the root-feeding larvae of the beetle Diabrotica virgifera virgifera, a major pest of maize. D. virgifera strongly avoided leaf-infested plants by recognizing systemic changes in soluble root components. The avoidance response occurred within 12 h and was induced by real and mimicked herbivory, but not wounding alone. Roots of leaf-infested plants showed altered patterns in soluble free and soluble conjugated phenolic acids. Biochemical inhibition and genetic manipulation of phenolic acid biosynthesis led to a complete disappearance of the avoidance response of D. virgifera. Furthermore, bioactivity-guided fractionation revealed a direct link between the avoidance response of D. virgifera and changes in soluble conjugated phenolic acids in the roots of leaf-attacked plants. Our study provides a physiological mechanism for a behavioral pattern that explains the negative effect of leaf attack on a root-feeding insect. Furthermore, it opens up the possibility to control D. virgifera in the field by genetically mimicking leaf herbivore-induced changes in root phenylpropanoid patterns. PMID:26430225

  2. Analysis of the Mechanical Behavior, Creep Resistance and Uniaxial Fatigue Strength of Martensitic Steel X46Cr13.

    PubMed

    Brnic, Josip; Krscanski, Sanjin; Lanc, Domagoj; Brcic, Marino; Turkalj, Goran; Canadija, Marko; Niu, Jitai

    2017-04-06

    The article deals with the analysis of the mechanical behavior at different temperatures, uniaxial creep and uniaxial fatigue of martensitic steel X46Cr13 (1.4034, AISI 420). For the purpose of considering the aforementioned mechanical behavior, as well as determining the appropriate resistance to creep and fatigue strength levels, numerous uniaxial tests were carried out. Tests related to mechanical properties performed at different temperatures are presented in the form of engineering stress-strain diagrams. Short-time creep tests performed at different temperatures and different stress levels are presented in the form of creep curves. Fatigue tests carried out at stress ratios R = 0.25 and R = - 1 are shown in the form of S-N (fatigue) diagrams. The finite fatigue regime for each of the mentioned stress ratios is modeled by an inclined log line, while the infinite fatigue regime is modeled by a horizontal line, which represents the fatigue limit of the material and previously was calculated by the modified staircase method. Finally, the fracture toughness has been calculated based on the Charpy V-notch impact energy.

  3. Analysis of the Mechanical Behavior, Creep Resistance and Uniaxial Fatigue Strength of Martensitic Steel X46Cr13

    PubMed Central

    Brnic, Josip; Krscanski, Sanjin; Lanc, Domagoj; Brcic, Marino; Turkalj, Goran; Canadija, Marko; Niu, Jitai

    2017-01-01

    The article deals with the analysis of the mechanical behavior at different temperatures, uniaxial creep and uniaxial fatigue of martensitic steel X46Cr13 (1.4034, AISI 420). For the purpose of considering the aforementioned mechanical behavior, as well as determining the appropriate resistance to creep and fatigue strength levels, numerous uniaxial tests were carried out. Tests related to mechanical properties performed at different temperatures are presented in the form of engineering stress-strain diagrams. Short-time creep tests performed at different temperatures and different stress levels are presented in the form of creep curves. Fatigue tests carried out at stress ratios R=0.25 and R=−1 are shown in the form of S–N (fatigue) diagrams. The finite fatigue regime for each of the mentioned stress ratios is modeled by an inclined log line, while the infinite fatigue regime is modeled by a horizontal line, which represents the fatigue limit of the material and previously was calculated by the modified staircase method. Finally, the fracture toughness has been calculated based on the Charpy V-notch impact energy. PMID:28772749

  4. Eating-related Behaviors and Appetite During Energy Imbalance in Obese-Prone and Obese-Resistant Individuals

    PubMed Central

    Thomas, Elizabeth A.; Bechtell, Jaime L.; Vestal, Brian E.; Johnson, Susan L.; Bessesen, Daniel H.; Tregellas, Jason R.; Cornier, Marc-Andre

    2013-01-01

    While the majority of Americans are now overweight, some individuals maintain their weight with minimal effort. This study investigated behavioral differences between 58 individuals recruited as either obese-resistant (OR) or obese-prone (OP) based on self-identification, BMI, and personal/family weight history. Subjects were studied during Eucaloric (EU), Overfed (OF), and Underfed (UF) phases which included a run-in diet, 1 day intervention diet, and a study day. At baseline, subjects completed the Three Factor Eating Questionnaire (TFEQ) and Power of Food Scale (PFS). On the study day, ratings of appetite, food appeal and desire, and food cravings were performed in response to a breakfast shake. OF resulted in reduced hunger and food desire while UF resulted in increased hunger and food appeal and desire. While hunger did not differ between groups, OP had higher scores for TFEQ measures (hunger, restraint and disinhibition), higher “hedonic hunger” as measured by the PFS, and greater food cravings and ratings of food appeal and desire. These results suggest that subjective hunger and desire for food change significantly after only one day of over- or underfeeding. Additionally, we found several behavioral differences between groups that are likely to promote weight gain over time in the OP. PMID:23402714

  5. Behaviorism

    ERIC Educational Resources Information Center

    Moore, J.

    2011-01-01

    Early forms of psychology assumed that mental life was the appropriate subject matter for psychology, and introspection was an appropriate method to engage that subject matter. In 1913, John B. Watson proposed an alternative: classical S-R behaviorism. According to Watson, behavior was a subject matter in its own right, to be studied by the…

  6. Behaviorism

    ERIC Educational Resources Information Center

    Moore, J.

    2011-01-01

    Early forms of psychology assumed that mental life was the appropriate subject matter for psychology, and introspection was an appropriate method to engage that subject matter. In 1913, John B. Watson proposed an alternative: classical S-R behaviorism. According to Watson, behavior was a subject matter in its own right, to be studied by the…

  7. Electrical Resistance Imaging for Evaluation of Soil-Water Behavior in Desert Ecosystems

    NASA Astrophysics Data System (ADS)

    Nimmo, J. R.; Perkins, K. S.; Schmidt, K. M.; Miller, D. M.; Stock, J. D.; Singha, K.

    2009-05-01

    As part of an effort to evaluate habitat types in the Mojave National Preserve, we conducted infiltration/redistribution experiments to investigate unsaturated hydraulic properties and soil-water dynamics. Two investigated locations contrasted sharply in degree of pedogenic development: (1) recently deposited sediments in an active wash and (2) a highly developed soil of late Pleistocene age. Water flow through these materials may be strongly influenced by such features as biotic crusts, vesicular horizons, textural variations, calcic horizons, preferential flow paths, and other forms of vertical and lateral spatial variability. In each location we ponded water in a 1-m-diameter infiltration ring for 2.3 h, generating 1.93 m of infiltration in the active wash and 0.52 m in the Pleistocene soil. Combining input flux data with quantitative knowledge of water content and soil water pressure over space and time provides a basis for estimating soil hydraulic properties. TDR probes and tensiometers, placed outside but within a few m of the infiltration pond at depths to 1.5 m, provided subsurface hydraulic data. In addition to probe measurements, we conducted electrical resistance imaging (ERI) measurements during the infiltration period and for six days of redistribution. Electrodes were in two crossed lines at the surface, 24 in each, at 0.5 m spacing. On each line data were collected over an eight- minute period using a hybrid geometry, with 0 to 6 electrodes skipped between those used for the measurement. Relative change in the inverted resistivities relates to relative change in soil water content. Spatially exhaustive and minimally invasive characterization is valuable because of the extreme difficulty of quantifying soil-moisture distribution over a broad heterogeneous area using a set of individual probes. Soil moisture data directly under the ponded area are especially important, and ERI was our only means for such measurements because probe installation would

  8. Multimodal behavioral treatment of nonrepetitive, treatment-resistant nightmares: a case report.

    PubMed

    Tanner, Barry A

    2004-12-01

    A 23-yr.-old young woman presenting with a 17-yr. history of nightmares was treated with a variety of behavioral and self-regulatory techniques. The nightmares were unusual in that they did not have an obviously common theme as in most published reports, and, therefore, did not readily lend themselves to several frequently used techniques. Although previous treatment episodes had not affected the incidence of the nightmares, a combination of relaxation procedures, a mnemonic to increase lucid dreaming, and dream rehearsal upon waking from a nightmare resulted in a sharp decrease in the frequency of nightmares in four sessions. Further improvement was reported over the next nine months as additional techniques were introduced and other problems treated, and was maintained during a 9-mo. follow-up.

  9. Highly Loaded Behavior of Kinesins Increases the Robustness of Transport Under High Resisting Loads

    PubMed Central

    Nam, Woochul; Epureanu, Bogdan I.

    2015-01-01

    Kinesins are nano-sized biological motors which walk by repeating a mechanochemical cycle. A single kinesin molecule is able to transport its cargo about 1 μm in the absence of external loads. However, kinesins perform much longer range transport in cells by working collectively. This long range of transport by a team of kinesins is surprising because the motion of the cargo in cells can be hindered by other particles. To reveal how the kinesins are able to accomplish their tasks of transport in harsh intracellular circumstances, stochastic studies on the kinesin motion are performed by considering the binding and unbinding of kinesins to microtubules and their dependence on the force acting on kinesin molecules. The unbinding probabilities corresponding to each mechanochemical state of kinesin are modeled. The statistical characterization of the instants and locations of binding are captured by computing the probability of unbound kinesin being at given locations. It is predicted that a group of kinesins has a more efficient transport than a single kinesin from the perspective of velocity and run length. Particularly, when large loads are applied, the leading kinesin remains bound to the microtubule for long time which increases the chances of the other kinesins to bind to the microtubule. To predict effects of this behavior of the leading kinesin under large loads on the collective transport, the motion of the cargo is studied when the cargo confronts obstacles. The result suggests that the behavior of kinesins under large loads prevents the early termination of the transport which can be caused by the interference with the static or moving obstacles. PMID:25734978

  10. Behavior of antibiotic resistance genes under extremely high-level antibiotic selection pressures in pharmaceutical wastewater treatment plants.

    PubMed

    Guo, Xinyan; Yan, Zheng; Zhang, Yi; Xu, Weili; Kong, Deyang; Shan, Zhengjun; Wang, Na

    2017-08-26

    comprehensive study on the behavior of antibiotic resistance genes under extremely high-level antibiotic selection pressures in pharmaceutical wastewater treatment plants (PWWTPs) in Southeastern China. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Behavior of antibiotics and antibiotic resistance genes in eco-agricultural system: A case study.

    PubMed

    Cheng, Weixiao; Li, Jianan; Wu, Ying; Xu, Like; Su, Chao; Qian, Yanyun; Zhu, Yong-Guan; Chen, Hong

    2016-03-05

    This study aims to determine abundance and persistence of antibiotics and antibiotic resistance genes (ARGs) in eco-agricultural system (EAS), which starts from swine feces to anaerobic digestion products, then application of anaerobic digestion solid residue (ADSR) and anaerobic digestion liquid residue (ADLR) to the soil to grow ryegrass, one of swine feed. Oxytetracycline had the highest concentration in manure reaching up to 138.7 mg/kg. Most of antibiotics could be effectively eliminated by anaerobic digestion and removal rates ranged from 11% to 86%. ARGs abundance fluctuated within EAS. TetQ had the highest relative abundance and the relative abundance of tetG had the least variation within the system, which indicates that tetG is persistent in the agricultural environment and requires more attention. Compared to the relative abundance in manure, tetC and tetM increased in biogas residue while three ribosomal protection proteins genes (tetO, tetQ, tetW) decreased (p<0.05), with other genes showing no significant change after anaerobic fermentation (p>0.05). Most ARGs in downstream components (soils and fishpond) of EAS showed significantly higher relative abundance than the control agricultural system (p<0.05), except for tetG and sulI.

  12. Synchronization behavior in linear arrays of negative differential resistance circuit elements

    NASA Astrophysics Data System (ADS)

    Xu, Huidong; Teitsworth, Stephen

    2008-03-01

    We study the electronic transport properties in a linear array of nonlinear circuit elements that exhibit negative differential resistance, and find that state-cluster synchronization emerges when there is heterogeneity in the element properties. This type of synchronization is associated with a non-uniform spatial distribution of total applied voltage across the array elements, as well as the formation of multiple stable branches in computed current-voltage curves for the entire array. Unlike most synchronizing systems studied previously [1], this system possesses coupling between elements that displays both positive and negative feedback depending on the state of each element. An empirical order parameter is defined which quantifies the degree of synchronization. We also find that the degree of synchronization is strongly dependent on the ramping rate of the total applied voltage to the array, with complete synchronization observed in the limit of small ramping rate. This model provides a basis for describing related nonlinear phenomena in more complex electronic structures such as semiconductor superlattices [2]. [1] A. Pikovsky, M. Rosenbaum, and Jürgen Kurths, Synchronization: a universal concept in nonlinear sciences (Cambridge University Press, Cambridge, 2001). [2] M. Rogozia, S. W. Teitsworth, H. T Grahn, and K. H. Ploog, Phys. Rev. B65, 205303 (2002).

  13. Interfacial behavior of resistive switching in ITO-PVK-Al WORM memory devices

    NASA Astrophysics Data System (ADS)

    Whitcher, T. J.; Woon, K. L.; Wong, W. S.; Chanlek, N.; Nakajima, H.; Saisopa, T.; Songsiriritthigul, P.

    2016-02-01

    Understanding the mechanism of resistive switching in a memory device is fundamental in order to improve device performance. The mechanism of current switching in a basic organic write-once read-many (WORM) memory device is investigated by determining the energy level alignments of indium tin oxide (ITO), poly(9-vinylcarbazole) (PVK) and aluminum (Al) using x-ray and ultraviolet photoelectron spectroscopy, current-voltage characterization and Auger depth profiling. The current switching mechanism was determined to be controlled by the interface between the ITO and the PVK. The electric field applied across the device causes the ITO from the uneven surface of the anode to form metallic filaments through the PVK, causing a shorting effect within the device leading to increased conduction. This was found to be independent of the PVK thickness, although the switch-on voltage was non-linearly dependent on the thickness. The formation of these filaments also caused the destruction of the interfacial dipole at the PVK-Al interface.

  14. Cranberry Resistance to Dodder Parasitism: Induced Chemical Defenses and Behavior of a Parasitic Plant.

    PubMed

    Tjiurutue, Muvari Connie; Sandler, Hilary A; Kersch-Becker, Monica F; Theis, Nina; Adler, Lynn A

    2016-02-01

    Parasitic plants are common in many ecosystems, where they can structure community interactions and cause major economic damage. For example, parasitic dodder (Cuscuta spp.) can cause up to 80-100 % yield loss in heavily infested cranberry (Vaccinium macrocarpon) patches. Despite their ecological and economic importance, remarkably little is known about how parasitic plants affect, or are affected by, host chemistry. To examine chemically-mediated interactions between dodder and its cranberry host, we conducted a greenhouse experiment asking whether: (1) dodder performance varies with cranberry cultivar; (2) cultivars differ in levels of phytohormones, volatiles, or phenolics, and whether such variation correlates with dodder parasitism; (3) dodder parasitism induced changes in phytohormones, volatiles, or phenolics, and whether the level of inducible response varied among cultivars. We used five cranberry cultivars to assess host attractiveness to dodder and dodder performance. Dodder performance did not differ across cultivars, but there were marginally significant differences in host attractiveness to dodder, with fewer dodder attaching to Early Black than to any other cultivar. Dodder parasitism induced higher levels of salicylic acid (SA) across cultivars. Cultivars differed in overall levels of flavonols and volatile profiles, but not phenolic acids or proanthocyanidins, and dodder attachment induced changes in several flavonols and volatiles. While cultivars differed slightly in resistance to dodder attachment, we did not find evidence of chemical defenses that mediate these interactions. However, induction of several defenses indicates that parasitism alters traits that could influence subsequent interactions with other species, thus shaping community dynamics.

  15. Differences in Stylet Penetration Behaviors of Glassy-winged Sharpshooters on Xylella-Resistant Vitis candicans vs. Susceptible Vitis vinifera cv. ‘Chardonnay’

    USDA-ARS?s Scientific Manuscript database

    Electrical penetration graph (EPG) monitoring was used to compare stylet penetration behaviors of glassy-winged sharpshooter (GWSS), a vector of Xylella fastidiosa (Xf), on Xf-resistant Vitis candicans grape vs. susceptible V. vinifera cv. ‘Chardonnay.’ Frequency of occurrence of X waves (represent...

  16. Predictions of fire behavior and resistance to control: for use with photo series for the sierra mixed conifer type and the sierra true fir type.

    Treesearch

    Franklin R. Ward; David V. Sandberg

    1981-01-01

    This publication presents tables on the behavior of fire and the resistance: of fuels to control. The information is to be used with the photos in the publication, "Photo Series for Quantifying Forest Residues in the Sierra Mixed Conifer Type, Sierra True Fir Type" (Maxwell, Wayne G.; Ward, Franklin R. 1979. Gen. Tech. Rep. PNW-GTR-095. Portland, OR: U.S....

  17. Predictions of fire behavior and resistance to control: for use with photo series for the ponderosa pine type, ponderosa pine and associated species type, and lodgepole pine type.

    Treesearch

    Franklin R. Ward; David V. Sandberg

    1981-01-01

    This publication presents tables on the behavior of fire and the resistance of fuels to control. The information is to be used with the publication, "Photo Series for Quantifying Forest Residues in the Ponderosa Pine Type, Ponderosa Pine and Associated Species Type, Lodgepole Pine Type" (Maxwell, Wayne G.; Ward, Franklin R. 1976. Gen. Tech. Rep. PNW-GTR-052....

  18. Preparing Digital Stories through the Inquiry-Based Learning Approach: Its Effect on Prospective Teachers' Resistive Behaviors toward Research and Technology-Based Instruction

    ERIC Educational Resources Information Center

    Yavuz Konokman, Gamze; Yanpar Yelken, Tugba

    2016-01-01

    The purpose of the study was to determine the effect of preparing digital stories through an inquiry based learning approach on prospective teachers' resistive behaviors toward technology based instruction and conducting research. The research model was convergent parallel design. The sample consisted of 50 prospective teachers who had completed…

  19. A light-modified ferroelectric resistive switching behavior in Ag/BaMoO{sub 4}/FTO device at ambient temperature

    SciTech Connect

    Zhao, W.X.; Sun, B.; Liu, Y.H.; Wei, L.J.; Li, H.W.; Chen, P.

    2014-12-15

    BaMoO{sub 4} powder was prepared by a facile hydrothermal synthesis. And the BaMoO{sub 4}/FTO device was fabricated by a spin-coated method, in which the thickness of BaMoO{sub 4} layer is about 20 µm. The bipolar resistive switching effect has been observed in Ag/BaMoO{sub 4}/FTO device. Moreover, the resistive switching effect of the device is greatly improved by white light irradiation. The resistive switching behavior is explained by the polarization reversal that changes the charge distribution and modulates the Schottky barriers. - Graphical abstract: We fabricate a resistive switching device based on Ag/BaMoO{sub 4}/FTO, the device shows superior white-light controlled bipolar resistive switching memristive characteristics. - Highlights: • The BaMoO{sub 4} nanosquares powder was prepared by a hydrothermal synthesis. • The resistive switching of the Ag/BaMoO{sub 4}/FTO device was observed for the first time. • It is shown that the resistive switching is greatly improved under the white light irradiation. • The mechanism of resistive switching is attributed to the ferroelectric polarization reversal.

  20. Study of self-compliance behaviors and internal filament characteristics in intrinsic SiO{sub x}-based resistive switching memory

    SciTech Connect

    Chang, Yao-Feng Zhou, Fei; Chen, Ying-Chen; Lee, Jack C.; Fowler, Burt

    2016-01-18

    Self-compliance characteristics and reliability optimization are investigated in intrinsic unipolar silicon oxide (SiO{sub x})-based resistive switching (RS) memory using TiW/SiO{sub x}/TiW device structures. The program window (difference between SET voltage and RESET voltage) is dependent on external series resistance, demonstrating that the SET process is due to a voltage-triggered mechanism. The program window has been optimized for program/erase disturbance immunity and reliability for circuit-level applications. The SET and RESET transitions have also been characterized using a dynamic conductivity method, which distinguishes the self-compliance behavior due to an internal series resistance effect (filament) in SiO{sub x}-based RS memory. By using a conceptual “filament/resistive gap (GAP)” model of the conductive filament and a proton exchange model with appropriate assumptions, the internal filament resistance and GAP resistance can be estimated for high- and low-resistance states (HRS and LRS), and are found to be independent of external series resistance. Our experimental results not only provide insights into potential reliability issues but also help to clarify the switching mechanisms and device operating characteristics of SiO{sub x}-based RS memory.

  1. Nanocrystalline Si pathway induced unipolar resistive switching behavior from annealed Si-rich SiN{sub x}/SiN{sub y} multilayers

    SciTech Connect

    Jiang, Xiaofan; Ma, Zhongyuan Yang, Huafeng; Yu, Jie; Wang, Wen; Zhang, Wenping; Li, Wei; Xu, Jun; Xu, Ling; Chen, Kunji; Huang, Xinfan; Feng, Duan

    2014-09-28

    Adding a resistive switching functionality to a silicon microelectronic chip is a new challenge in materials research. Here, we demonstrate that unipolar and electrode-independent resistive switching effects can be realized in the annealed Si-rich SiN{sub x}/SiN{sub y} multilayers with high on/off ratio of 10{sup 9}. High resolution transmission electron microscopy reveals that for the high resistance state broken pathways composed of discrete nanocrystalline silicon (nc-Si) exist in the Si nitride multilayers. While for the low resistance state the discrete nc-Si regions is connected, forming continuous nc-Si pathways. Based on the analysis of the temperature dependent I-V characteristics and HRTEM photos, we found that the break-and-bridge evolution of nc-Si pathway is the origin of resistive switching memory behavior. Our findings provide insights into the mechanism of the resistive switching behavior in nc-Si films, opening a way for it to be utilized as a material in Si-based memories.

  2. Aerobic physical activity and resistance training: an application of the theory of planned behavior among adults with type 2 diabetes in a random, national sample of Canadians.

    PubMed

    Plotnikoff, Ronald C; Courneya, Kerry S; Trinh, Linda; Karunamuni, Nandini; Sigal, Ronald J

    2008-12-02

    Aerobic physical activity (PA) and resistance training are paramount in the treatment and management of type 2 diabetes (T2D), but few studies have examined the determinants of both types of exercise in the same sample. The primary purpose was to investigate the utility of the Theory of Planned Behavior (TPB) in explaining aerobic PA and resistance training in a population sample of T2D adults. A total of 244 individuals were recruited through a random national sample which was created by generating a random list of household phone numbers. The list was proportionate to the actual number of household telephone numbers for each Canadian province (with the exception of Quebec). These individuals completed self-report TPB constructs of attitude, subjective norm, perceived behavioral control and intention, and a 3-month follow-up that assessed aerobic PA and resistance training. TPB explained 10% and 8% of the variance respectively for aerobic PA and resistance training; and accounted for 39% and 45% of the variance respectively for aerobic PA and resistance training intentions. These results may guide the development of appropriate PA interventions for aerobic PA and resistance training based on the TPB.

  3. Correlation of proteome-wide changes with social immunity behaviors provides insight into resistance to the parasitic mite, Varroa destructor, in the honey bee (Apis mellifera)

    PubMed Central

    2012-01-01

    Background Disease is a major factor driving the evolution of many organisms. In honey bees, selection for social behavioral responses is the primary adaptive process facilitating disease resistance. One such process, hygienic behavior, enables bees to resist multiple diseases, including the damaging parasitic mite Varroa destructor. The genetic elements and biochemical factors that drive the expression of these adaptations are currently unknown. Proteomics provides a tool to identify proteins that control behavioral processes, and these proteins can be used as biomarkers to aid identification of disease tolerant colonies. Results We sampled a large cohort of commercial queen lineages, recording overall mite infestation, hygiene, and the specific hygienic response to V. destructor. We performed proteome-wide correlation analyses in larval integument and adult antennae, identifying several proteins highly predictive of behavior and reduced hive infestation. In the larva, response to wounding was identified as a key adaptive process leading to reduced infestation, and chitin biosynthesis and immune responses appear to represent important disease resistant adaptations. The speed of hygienic behavior may be underpinned by changes in the antenna proteome, and chemosensory and neurological processes could also provide specificity for detection of V. destructor in antennae. Conclusions Our results provide, for the first time, some insight into how complex behavioural adaptations manifest in the proteome of honey bees. The most important biochemical correlations provide clues as to the underlying molecular mechanisms of social and innate immunity of honey bees. Such changes are indicative of potential divergence in processes controlling the hive-worker maturation. PMID:23021491

  4. The oxidation behavior of SiC sintered with Al-B-C and improved oxidation resistance via heat treatments

    SciTech Connect

    Sixta, Mark

    1997-12-01

    The oxidation behavior of high strength and high toughness SiC, sintered with Al, B, and C (ABC-SiC), was examined. Kinetic data were acquired and the parabolic rate constant for oxidation was determined and compared with literature data on various SiC materials. The role of secondary phases on the oxide morphology was explored. ABC-SiC was compared to commercially available SiC, Hexoloy, and SiC sintered with 10% yttrium aluminum garnet (YAG). Two-step sintering (pre-coarsening) was employed with holds for 48 hours at 600-1,600°C, prior to the typical hot-pressing conditions of 1,900°C for 1 hour, to change the chemistry and reduce the number of bubbles in the silica scale. The effects on the oxide thickness and integrity was examined as a function of the precoarsening heat treatment temperature. Additionally, the hot-pressed ABC-SiC was subjected to heat treatments (anneals) at 1,800°C for 1 hour in nitrogen, Ar, and vacuum environments, and the effects on subsequent oxidation were evaluated. The Ar and vacuum heat treatments dramatically improved the oxidation resistance of ABC-SiC. Finally, reoxidation experiments were performed to try to alter the surface chemistry of the SiC to improve the oxidation resistance. The four-point bend strengths and two-parameter Weibull plots of the most successful heat treatments were compared with the standard ABC-SiC to ensure that significant degradation did not result from altering the processing of the material.

  5. Acquired BRAF inhibitor resistance: a multicenter meta-analysis of the spectrum and frequencies, clinical behavior, and phenotypic associations of resistance mechanisms

    PubMed Central

    Johnson, Douglas B.; Menzies, Alexander M.; Zimmer, Lisa; Eroglu, Zeynep; Ye, Fei; Zhao, Shilin; Rizos, Helen; Sucker, Antje; Scolyer, Richard A.; Gutzmer, Ralf; Gogas, Helen; Kefford, Richard F.; Thompson, John F.; Becker, Jürgen C.; Berking, Carola; Egberts, Friederike; Loquai, Carmen; Goldinger, Simone M.; Pupo, Gulietta M.; Hugo, Willy; Kong, Xiangju; Garraway, Levi A.; Sosman, Jeffrey A.; Ribas, Antoni; Lo, Roger S.; Long, Georgina V.; Schadendorf, Dirk

    2015-01-01

    Background Acquired resistance to BRAF inhibitors (BRAFi) is a near-universal phenomenon caused by numerous genetic and non-genetic alterations. In this study, we evaluated the spectrum, onset, pattern of progression, and subsequent clinical outcomes associated with specific mechanisms of resistance. Methods We compiled clinical and genetic data from 100 patients with 132 tissue samples obtained at progression on BRAFi therapy from 3 large, previously published studies of BRAFi resistance. These samples were subjected to whole exome sequencing and/or PCR-based genetic testing. Results Among 132 samples, putative resistance mechanisms were identified in 58%, including NRAS or KRAS mutations (20%), BRAF splice variants (16%), BRAFV600E/K amplifications (13%), MEK1/2 mutations (7%), and non-MAPK pathway alterations (11%). Marked heterogeneity was observed within tumors and patients; 18 of 19 patients (95%) with >1 progression biopsy had distinct/unknown drivers of resistance between samples. NRAS mutations were associated with vemurafenib use (p=0.045) and intracranial metastases (p=0.036), and MEK1/2 mutations correlated with hepatic progression (p=0.011). Progression-free survival and overall survival were similar across resistance mechanisms. The median survival after disease progression was 6.9 months, and responses to subsequent BRAF and MEK inhibition were uncommon (2 of 15; 13%). Post-progression outcomes did not correlate with specific acquired BRAFi resistance mechanisms. Conclusions This is the first study to systematically characterize the clinical implications of particular acquired BRAFi resistance mechanisms in patients with BRAF-mutant melanoma largest study to compile the landscape of resistance. Despite marked heterogeneity of resistance mechanisms within patients, NRAS mutations correlated with vemurafenib use and intracranial disease involvement. PMID:26608120

  6. Highly flexible and electroforming free resistive switching behavior of tungsten disulfide flakes fabricated through advanced printing technology

    NASA Astrophysics Data System (ADS)

    Muqeet Rehman, Muhammad; Uddin Siddiqui, Ghayas; Doh, Yang Hoi; Choi, Kyung Hyun

    2017-09-01

    Tungsten disulfide (WS2) is a transition metal dichalcogenide that differs from other 2D materials such as graphene owing to its distinctive semiconducting nature and tunable band gap. In this study, we have reported the structural, electrical, physical, and mechanical properties of exfoliated WS2 flakes and used them as the functional layer of a rewritable bipolar memory device. We demonstrate this concept by sandwiching few-layered WS2 flakes between two silver (Ag) electrodes on a flexible and transparent PET substrate. The entire device fabrication was carried out through all-printing technology such as reverse offset printing for patterning bottom electrodes, electrohydrodynamic (EHD) atomization for depositing functional thin film and EHD patterning for depositing the top electrode respectively. The memory device was further encapsulated with an atomically thin layer of aluminum oxide (Al2O3), deposited through a spatial atmospheric atomic layer deposition system to protect it against a humid environment. Remarkable resistive switching results were obtained, such as nonvolatile bipolar behavior, a high switching ratio (∼103), a long retention time (∼105 s), high endurance (1500 voltage sweeps), a low operating voltage (∼2 V), low current compliance (50 μA), mechanical robustness (1500 cycles) and unique repeatability at ambient conditions. Ag/WS2/Ag-based memory devices offer a new possibility for integration in flexible electronic devices.

  7. Effects of Prolonged GRP78 Haploinsufficiency on Organ Homeostasis, Behavior, Cancer and Chemotoxic Resistance in Aged Mice

    PubMed Central

    Lee, Amy S.; Brandhorst, Sebastian; Rangel, Daisy F.; Navarrete, Gerardo; Cohen, Pinchas; Longo, Valter D.; Chen, Jeannie; Groshen, Susan; Morgan, Todd E.; Dubeau, Louis

    2017-01-01

    GRP78, a multifunctional protein with potent cytoprotective properties, is an emerging therapeutic target to combat cancer development, progression and drug resistance. The biological consequences of prolonged reduction in expression of this essential chaperone which so far has been studied primarily in young mice, was investigated in older mice, as older individuals are likely to be important recipients of anti-GRP78 therapy. We followed cohorts of Grp78+/+ and Grp78+/− male and female mice up to 2 years of age in three different genetic backgrounds and characterized them with respect to body weight, organ integrity, behavioral and memory performance, cancer, inflammation and chemotoxic response. Our results reveal that body weight, organ development and integrity were not impaired in aged Grp78+/− mice. No significant effect on cancer incidence and inflammation was observed in aging mice. Interestingly, our studies detected some subtle differential trends between the WT and Grp78+/− mice in some test parameters dependent on gender and genetic background. Our studies provide the first evidence that GRP78 haploinsufficiency for up to 2 years of age has no major deleterious effect in rodents of different genetic background, supporting the merit of anti-GRP78 drugs in treatment of cancer and other diseases affecting the elderly. PMID:28145503

  8. Tensile deformation behavior of spray-deposited FVS0812 heat-resistant aluminum alloy sheet at elevated temperatures

    SciTech Connect

    Yan Qiqi; Fu Dingfa . E-mail: Fudingfa69@163.com; Deng Xuefeng; Zhang Hui; Chen Zhenhua

    2007-06-15

    The tensile deformation behavior of spray deposited FVS0812 heat-resistant aluminum alloy sheet was studied by uniaxial tension tests at temperatures ranging from 250 deg. C to 450 deg. C and strain rates from 0.001 to 0.1 s{sup -1}. The associated fracture surfaces were examined by scanning electron microscopy (SEM). The results show that the degree of work-hardening increases with decreasing temperature, and exhibits a small decrease with increasing strain rate; the strain rate sensitivity exponent increases with increasing temperature. The flow stress increases with increasing strain rate but decreases with increasing temperature. The total elongations to fracture increase not only with increasing temperature, but also with increasing strain rate, which is in marked contrast with the normal inverse dependence of elongation on the strain rate exhibited by conventional aluminum alloy sheets. The SEM fracture analysis indicates that the dependence of elongation on the strain rate may be due to the presence of a transition from plastic instability at lower strain rates to stable deformation at higher strain rates for fine-grained materials produced by spray deposition.

  9. Deformation Behavior of Laser Welds in High Temperature Oxidation Resistant Fe-Cr-Al Alloys for Fuel Cladding Applications

    SciTech Connect

    Field, Kevin G; Gussev, Maxim N; Yamamoto, Yukinori; Snead, Lance Lewis

    2014-11-01

    Ferritic-structured Fe-Cr-Al alloys are being developed and show promise as oxidation resistant accident tolerant light water reactor fuel cladding. This study focuses on investigating the weldability of three model alloys in a range of Fe-(13-17.5)Cr-(3-4.4)Al in weight percent with a minor addition of yttrium using laser-welding techniques. A detailed study on the mechanical performance of bead-on-plate welds has been carried out to determine the performance of welds as a function of alloy composition. Laser welding resulted in a defect free weld devoid of cracking or inclusions for all alloys studied. Results indicated a reduction in the yield strength within the fusion zone compared to the base metal. Yield strength reduction was found to be primarily constrained to the fusion zone due to grain coarsening with a less severe reduction in the heat affected zone. No significant correlation was found between the deformation behavior/mechanical performance of welds and the level of Cr or Al in the alloy ranges studied.

  10. Structural Phase Transition Effect on Resistive Switching Behavior of MoS2 -Polyvinylpyrrolidone Nanocomposites Films for Flexible Memory Devices.

    PubMed

    Zhang, Peng; Gao, Cunxu; Xu, Benhua; Qi, Lin; Jiang, Changjun; Gao, Meizhen; Xue, Desheng

    2016-04-01

    The 2H phase and 1T phase coexisting in the same molybdenum disulfide (MoS2 ) nanosheets can influence the electronic properties of the materials. The 1T phase of MoS2 is introduced into the 2H-MoS2 nanosheets by two-step hydrothermal synthetic methods. Two types of nonvolatile memory effects, namely write-once read-many times memory and rewritable memory effect, are observed in the flexible memory devices with the configuration of Al/1T@2H-MoS2 -polyvinylpyrrolidone (PVP)/indium tin oxide (ITO)/polyethylene terephthalate (PET) and Al/2H-MoS2 -PVP/ITO/PET, respectively. It is observed that structural phase transition in MoS2 nanosheets plays an important role on the resistive switching behaviors of the MoS2 -based device. It is hoped that our results can offer a general route for the preparation of various promising nanocomposites based on 2D nanosheets of layered transition metal dichalcogenides for fabricating the high performance and flexible nonvolatile memory devices through regulating the phase structure in the 2D nanosheets.

  11. Effects of Prolonged GRP78 Haploinsufficiency on Organ Homeostasis, Behavior, Cancer and Chemotoxic Resistance in Aged Mice.

    PubMed

    Lee, Amy S; Brandhorst, Sebastian; Rangel, Daisy F; Navarrete, Gerardo; Cohen, Pinchas; Longo, Valter D; Chen, Jeannie; Groshen, Susan; Morgan, Todd E; Dubeau, Louis

    2017-02-01

    GRP78, a multifunctional protein with potent cytoprotective properties, is an emerging therapeutic target to combat cancer development, progression and drug resistance. The biological consequences of prolonged reduction in expression of this essential chaperone which so far has been studied primarily in young mice, was investigated in older mice, as older individuals are likely to be important recipients of anti-GRP78 therapy. We followed cohorts of Grp78(+/+) and Grp78(+/-) male and female mice up to 2 years of age in three different genetic backgrounds and characterized them with respect to body weight, organ integrity, behavioral and memory performance, cancer, inflammation and chemotoxic response. Our results reveal that body weight, organ development and integrity were not impaired in aged Grp78(+/-) mice. No significant effect on cancer incidence and inflammation was observed in aging mice. Interestingly, our studies detected some subtle differential trends between the WT and Grp78(+/-) mice in some test parameters dependent on gender and genetic background. Our studies provide the first evidence that GRP78 haploinsufficiency for up to 2 years of age has no major deleterious effect in rodents of different genetic background, supporting the merit of anti-GRP78 drugs in treatment of cancer and other diseases affecting the elderly.

  12. Deformation behavior of laser welds in high temperature oxidation resistant Fe-Cr-Al alloys for fuel cladding applications

    NASA Astrophysics Data System (ADS)

    Field, Kevin G.; Gussev, Maxim N.; Yamamoto, Yukinori; Snead, Lance L.

    2014-11-01

    Ferritic-structured Fe-Cr-Al alloys are being developed and show promise as oxidation resistant accident tolerant light water reactor fuel cladding. This study focuses on investigating the weldability and post-weld mechanical behavior of three model alloys in a range of Fe-(13-17.5)Cr-(3-4.4)Al (wt.%) with a minor addition of yttrium using modern laser-welding techniques. A detailed study on the mechanical performance of bead-on-plate welds using sub-sized, flat dog-bone tensile specimens and digital image correlation (DIC) has been carried out to determine the performance of welds as a function of alloy composition. Results indicated a reduction in the yield strength within the fusion zone compared to the base metal. Yield strength reduction was found to be primarily constrained to the fusion zone due to grain coarsening with a less severe reduction in the heat affected zone. For all proposed alloys, laser welding resulted in a defect free weld devoid of cracking or inclusions.

  13. Supervisee Resistance. ERIC Digest.

    ERIC Educational Resources Information Center

    Bradley, Loretta J.; Gould, L. J.

    This digest focuses on issues of supervisee resistance, defined as defensive behaviors of the supervisee that serve to reduce supervision-induced anxiety. It describes resistant behavior and identifies ways to counteract it, while noting that supervisee resistance is common. The purposes and goals of supervisee resistance, as manifested in verbal…

  14. Prevalence and behavior of multidrug-resistant shiga toxin-producing Escherichia coli, enteropathogenic E. coli and enterotoxigenic E. coli on coriander.

    PubMed

    Gómez-Aldapa, Carlos A; Segovia-Cruz, Jesús A; Cerna-Cortes, Jorge F; Rangel-Vargas, Esmeralda; Salas-Rangel, Laura P; Gutiérrez-Alcántara, Eduardo J; Castro-Rosas, Javier

    2016-10-01

    The prevalence and behavior of multidrug-resistant diarrheagenic Escherichia coli pathotypes on coriander was determined. One hundred coriander samples were collected from markets. Generic E. coli were determined using the most probable number procedure. Diarrheagenic E. coli pathotypes (DEPs) were identified using two multiplex polymerase chain reaction procedures. Susceptibility to sixteen antibiotics was tested for the isolated DEPs strains by standard test. The behavior of multidrug-resistant DEPs isolated from coriander was determined on coriander leaves and chopped coriander at 25°± 2 °C and 3°± 2 °C. Generic E. coli and DEPs were identified, respectively, in 43 and 7% of samples. Nine DEPs strains were isolated from positive coriander samples. The identified DEPs included Shiga toxin-producing E. coli (STEC, 4%) enterotoxigenic E. coli (ETEC, 2%) and enteropathogenic E. coli (EPEC, 1%). All isolated DEPs strains exhibited multi-resistance to antibiotics. On inoculated coriander leaves stored at 25°± 2 °C or 3°± 2 °C, no growth was observed for multidrug-resistant DEPs strains. However, multidrug-resistant DEPs strains grew in chopped coriander: after 24 h at 25° ± 2 °C, DEPs strains had grown to approximately 3 log CFU/g. However, at 3°± 2 °C the bacterial growth was inhibited. To the best of our knowledge, this is the first report of the presence and behavior of multidrug-resistant STEC, ETEC and EPEC on coriander and chopped coriander. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. Using positive images to manage resistance-to-care and combative behaviors in nursing home residents with dementia: A pilot study.

    PubMed

    Chou, Wei-Ying; Waszynski, Christine; Kessler, Jeanne; Chiang, Yu-Ching; Clarkson, P John

    2016-01-01

    This pilot study attempted to reduce resistance-to-care (RTC) and combative behaviors in nursing home residents with dementia by eliciting their positive affect. Four female residents with dementia were recruited from a nursing facility. Each resident was involved in one intervention trial and one control trial. The response of the residents was assessed by the Agitated Behavior Scale and the Observational Measurement of Engagement Tool. The distress level of the certified nursing assistants (CNAs) delivering the care was reported through the Distress Thermometer. Results showed that the residents displayed fewer behavioral symptoms in the intervention trial than in the control trial. The CNAs reported less distress in the intervention trial than in the control trial. These preliminary findings suggest that it might be feasible to use positive images to reduce residents' behavioral symptoms and decrease the distress of CNAs. Copyright © 2016 Elsevier Inc. All rights reserved.

  16. Resistance Is Not Futile: An Experimental Analogue of the Effects of Consultee "Resistance" on the Consultant's Therapeutic Behavior in the Consultation Process--A Replication and Extension

    ERIC Educational Resources Information Center

    Cautilli, Joseph; Tillman, T. Chris; Axelrod, Saul; Dziewolska, Halina; Hineline, Philip

    2006-01-01

    In the school system, school psychologist serves a role as consultant to teachers in regard to children's behavioral problems (Bergan & Kratochwill, 1990). The defining feature of children's success is plan implementation (Bergan & Kratochwill, 1990). For school psychologists, ensuring consistent and accurate implementation of behavior strategies…

  17. Plant resistance to aphid feeding: behavioral, physiological, genetic and molecular cues regulate aphid host selection and feeding.

    PubMed

    Smith, C Michael; Chuang, Wen-Po

    2014-04-01

    Aphids damage major world food and fiber crops through direct feeding and transmission of plant viruses. Fortunately, the development of many aphid-resistant crop plants has provided both ecological and economic benefits to food production. Plant characters governing aphid host selection often dictate eventual plant resistance or susceptibility to aphid herbivory, and these phenotypic characters have been successfully used to map aphid resistance genes. Aphid resistance is often inherited as a dominant trait, but is also polygenic and inherited as recessive or incompletely dominant traits. Most aphid-resistant cultivars exhibit constitutively expressed defenses, but some cultivars exhibit dramatic aphid-induced responses, resulting in the overexpression of large ensembles of putative aphid resistance genes. Two aphid resistance genes have been cloned. Mi-1.2, an NBS-LRR gene from wild tomato, confers resistance to potato aphid and three Meloidogyne root-knot nematode species, and Vat, an NBS-LRR gene from melon, controls resistance to the cotton/melon aphid and to some viruses. Virulence to aphid resistance genes of plants occurs in 17 aphid species--more than half of all arthropod biotypes demonstrating virulence. The continual appearance of aphid virulence underscores the need to identify new sources of resistance of diverse sequence and function in order to delay or prevent biotype development.

  18. Composition of thin Ta2O5 films deposited by different methods and the effect of humidity on their resistive switching behavior

    NASA Astrophysics Data System (ADS)

    Mannequin, Cedric; Tsuruoka, Tohru; Hasegawa, Tsuyoshi; Aono, Masakazu

    2016-06-01

    The resistive switching behavior of Cu/Ta2O5/Pt atomic switches, in which the Ta2O5 film was deposited by electron-beam (EB) evaporation and radio-frequency sputtering (SP), was investigated under different relative humidity (RH) levels. Fourier-transformed infrared spectroscopy and X-ray photoelectron spectroscopy measurements revealed that both films possess the oxygen-rich composition and higher water absorption capability of EB films. The Cu/Ta2O5-SP/Pt cell showed a stable, nonvolatile switching behavior in the observed RH range, whereas the Cu/Ta2O5-EB/Pt cell exhibited a similar behavior up to 50% RH, but altered from nonvolatile to volatile switching at higher RH levels. The observed volatile switching behavior of the Cu/Ta2O5-EB/Pt cell can be explained by increased ion migration, assisted by absorbed water and/or proton conduction in hydrated environments. The results indicate that the water uptake ability of the matrix film plays a crucial role in determining the resistive switching behavior of oxide-based atomic switches.

  19. Rufinamide Improves Functional and Behavioral Deficits via Blockade of Tetrodotoxin-Resistant Sodium Channels in Diabetic Neuropathy.

    PubMed

    Kharatmal, Shivsharan B; Singh, Jitendra N; Sharma, Shyam S

    2015-01-01

    Rufinamide is a structurally novel, antiepileptic drug approved for the treatment of Lennox-Gastaut syndrome. Its mechanism of action involves inhibition of voltage-gated Na+ channels (VGSCs) with possible membrane-stabilizing effects. VGSCs play a significant role in the pathogenesis of neuropathic pain. Therefore, we investigated the effects of rufinamide on tetrodotoxin-resistant sodium current (TTX-R I(Na)) in acutely dissociated rat dorsal root ganglion (DRG) neurons isolated from streptozotocin-induced diabetic rats by using whole-cell voltage-clamp configuration. In addition, the functional and behavioural nociceptive parameters were evaluated to assess its potential in diabetic neuropathy. Diabetic rats demonstrated the mechanical allodynia and thermal hyperalgesia with reduced nerve perfusion and conduction velocity as compared to control. Rufinamide treatments (3 and 10 mg/kg) significantly improved these functional and nociceptive deficits. Diabetic rat DRG neurons exhibited increased TTX-R I(Na) density as compared to control. The voltage-dependent activation and steady-state inactivation curves for TTX-R I(Na) in DRG neurons from diabetic rats were shifted negatively as compared to control. Rufinamide treatments significantly blocked the TTX-R Na+ channel activity as evident from significant reduction in I(Na) density and hyperpolarizing shift in activation and inactivation curves as compared to diabetic control. This suggests that rufinamide acts on TTX-R Na+ channels, reduces channel activity and attenuates nerve functional and behavioral parameters in diabetic rats. Altogether, these results indicate therapeutic potential of rufinamide in the treatment of diabetic neuropathy.

  20. Effects of partial interlaminar bonding on impact resistance and loaded-hole behavior of graphite/epoxy quasi-isotropic laminates

    NASA Technical Reports Server (NTRS)

    Illg, W.

    1986-01-01

    A partial-bonding interlaminar toughening concept was evaluated for resistance to impact and for behavior of a loaded hole. Perforated Mylar sheets were interleaved between all 24 plies of a graphite/epoxy quasi-isotropic lay-up. Specimens were impacted by aluminum spheres while under tensile or compressive loads. Impact-failure thresholds and residual strengths were obtained. Loaded-hole specimens were tested in three configurations that were critical in bearing, shear, or tension. Partial bonding reduced the tensile and compressive strengths of undamaged specimens by about one-third. For impact, partial bonding did not change the threshold for impact failure under tensile preload. However, under compressive preload, partial bonding caused serious degradation of impact resistance. Partial bonding reduced the maximum load-carrying capacity of all three types of loaded-hole specimens. Overall, partial bonding degraded both impact resistance and bearing strength of holes.

  1. Predictions of fire behavior and resistance to control: for use with photo series for the Douglas fir-hemlock type and the coastal Douglas-fir-hardwood type.

    Treesearch

    David V. SANDBERG; Franklin R. Ward

    1981-01-01

    This publication presents tables on the behavior of fire and the resistance of fuels to control. The information is to be used with the photos in the publication, "Photo Series for Quantifying Forest Residues in the Coastal Douglas-fir—Hemlock Type, Coastal Douglas-fir—Hardwood Type" (Maxwell, Wayne G.; Ward, Franklin R. 1976. Gen. Tech. Rep. PNW-GTR-051....

  2. Prevalence and behavior of multidrug-resistant Salmonella strains on raw whole and cut nopalitos (Opuntia ficus-indica L.) and on nopalitos salads.

    PubMed

    Gómez-Aldapa, Carlos A; Gutiérrez-Alcántara, Eduardo J; Torres-Vitela, M Refugio; Rangel-Vargas, Esmeralda; Villarruel-López, Angelica; Castro-Rosas, Javier

    2017-09-01

    The presence of multidrug-resistant Salmonella in vegetables is a significant public health concern. Nopalito is a cactaceous that is commonly consumed either raw or cooked in Mexico and other countries. The presence of antibiotic-resistant Salmonella strains on raw whole nopalitos (RWN, without prickles), raw nopalitos cut into squares (RNCS) and in cooked nopalitos salads (CNS) samples was determined. In addition, the behavior of multidrug-resistant Salmonella isolates on RWN, RNCS and CNS at 25° ± 2 °C and 3° ± 2 °C was investigated. One hundred samples of RWN, 100 of RNCS and 100 more of CNS were collected from public markets. Salmonella strains were isolated and identified in 30, 30 and 10% of the samples, respectively. Seventy multidrug-resistant Salmonella strains were isolated from all the nopalitos samples. Multidrug-resistant Salmonella isolates survived at least 15 days on RWN at 25° ± 2 °C or 3° ± 2 °C. Multidrug-resistant Salmonella isolates grew in the RNCS and CNS samples at 25° ± 2 °C. However, at 3° ± 2 °C the bacterial growth was inhibited. This is the first report about multidrug-resistant Salmonella isolation from raw nopalitos and nopalitos salads. Nopalitos from markets are very likely to be an important factor contributing to the endemicity of multidrug-resistant Salmonella-related gastroenteritis in Mexico. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  3. Effect of Ultrasonic Vibration on the Behavior of Antifriction and Wear Resistance of Al2O3/Al2O3 Ceramic Friction Pairs Under Oil Lubrication

    NASA Astrophysics Data System (ADS)

    Dong, X. Y.; Qiao, Y. L.; Zang, Y.; Cui, Q. S.

    The behavior of antifriction and wear resistance of Al2O3/Al2O3 ceramic friction pairs lubricated by four different lubrication oils under ultrasonic vibration was studied. The surface morphologies of wear scare was analyzed by metallographic microscope. The effect mechanism of ultrasonic vibration on frictional pairs under different lubrication oils was discussed. The studied results showed that, ultrasonic vibration would improve the behavior of antifriction and wear resistance of the Al2O3/Al2O3 ceramic friction pairs under various lubrication oils.The improving would be dramaticer when the viscosity of lubrication oil was low. Ultrasonic vibration decreased the friction coefficient and wear volume 12.9% and 38.7% respectively, when the lubrication oil was 6#,the viscosity of which is 39.77 mm2/s. When the lubrication oil was 150BS, the viscosity of which is 549.69 mm2/s, ultrasonic vibration made friction coefficient and wear volume decreased 4.6% and 11.6% respectively.The effect of ultrasonic vibration on the behavior of antifriction and wear resistance of Al2O3/Al2O3 ceramic friction pairs was determined by the formation and the destruction of oil film on the friction surface and the upward floatage created by ultrasonic vibration.

  4. Sensitivity of landscape resistance estimates based on point selection functions to scale and behavioral state: Pumas as a case study

    Treesearch

    Katherine A. Zeller; Kevin McGarigal; Paul Beier; Samuel A. Cushman; T. Winston Vickers; Walter M. Boyce

    2014-01-01

    Estimating landscape resistance to animal movement is the foundation for connectivity modeling, and resource selection functions based on point data are commonly used to empirically estimate resistance. In this study, we used GPS data points acquired at 5-min intervals from radiocollared pumas in southern California to model context-dependent point selection...

  5. Why Do Children Resist or Obey Their Foster Parents? The Inner Logic of Children's Behavior during Discipline

    ERIC Educational Resources Information Center

    Singer, Elly; Doornenbal, Jeannette; Okma, Krista

    2004-01-01

    This article discusses a study of children's perspectives on disciplinary conflicts with their foster parents. Most children accept parental authority, but they also defend their personal autonomy and loyalties to peers. In this study, only birthchildren told real-life stories about fierce resistance to get their own way. Fierce resistance among…

  6. Why Do Children Resist or Obey Their Foster Parents? The Inner Logic of Children's Behavior during Discipline

    ERIC Educational Resources Information Center

    Singer, Elly; Doornenbal, Jeannette; Okma, Krista

    2004-01-01

    This article discusses a study of children's perspectives on disciplinary conflicts with their foster parents. Most children accept parental authority, but they also defend their personal autonomy and loyalties to peers. In this study, only birthchildren told real-life stories about fierce resistance to get their own way. Fierce resistance among…

  7. Pyrethroid Resistance Alters the Blood-Feeding Behavior in Puerto Rican Aedes aegypti Mosquitoes Exposed to Treated Fabric

    USDA-ARS?s Scientific Manuscript database

    Emerging insecticide resistance is a major issue for vector control; it decreases effectiveness of insecticides, thereby requiring greater quantities for comparable control with a net increase in risk of disease resurgence, product cost, and damage risk to the ecosystem. Pyrethroid resistance has b...

  8. Effect of microstructure on the corrosion and deformation behavior of a newly developed 6Mn-5Cr-1.5Cu corrosion-resistant white iron

    NASA Astrophysics Data System (ADS)

    Rao, P. N. V. R. S. S. V. Prasada; Patwardhan, A. K.; Jain, N. C.

    1993-02-01

    An experimental study has been made of the effect of heat treatment on the transformation behavior of a 4.8 pct Cr white iron, alloyed with 6 pct Mn and 1.5 pct Cu, by employing optical metallography, X-ray diffractometry, and differential thermal analysis (DTA) techniques, with a view to assess the suitability of the different microstructures in resisting aqueous corrosion. The matrix microstructure in the as-cast condition, comprising pearlite + bainite/martensite, transformed to austenite on heat-treating at all the temperatures between 900 °C and 1050 °C. Increasing the soaking period at each of the heat-treating temperatures led to an increase in the volume fraction and stability of austenite. M3C was the dominant carbide present in the as-cast condition. On heat-treating, different carbides formed: M23C6 carbide was present on heat-treating at 900 °C and 950 °C; on heat-treating at 1000 °C, M7C3 formed and persisted even on heattreating at 1050 °C. The possible formation of M5C2 carbide in the as-cast and heat-treated conditions (900 °C and 950 °C) is also indicated. Dispersed carbides (DC), present in austenite up to 950 °C, mostly comprised M3C and M5C2. On stress relieving of the heat-treated samples, M7C3-type DC also formed. The hardness changes were found to be consistent with the micro-structural changes occurring on heat-treating. The as-cast state was characterized by a reasonable resistance to corrosion in 5 pct NaCl solution. On heat-treating, the corrosion resistance improved over that in the as-cast state. After 4 hours soaking, increasing the temperature from 900 °C to 1050 °C led to an improvement in corrosion resistance. However, after 10 hours soaking, corrosion resistance decreased on increasing the temperature from 900 °C to 950 °C and improved thereafter on increasing the heat-treating temperature. Deformation behavior responded to the microstructure on similar lines as the corrosion behavior. Although in an early stage of

  9. Correlation between Electrical Resistivity, Particle Dissolution, Precipitation of Dispersoids, and Recrystallization Behavior of AA7020 Aluminum Alloy

    NASA Astrophysics Data System (ADS)

    Eivani, A. R.; Ahmed, H.; Zhou, J.; Duszczyk, J.

    2009-10-01

    This research concerns the effect of homogenization treatment on the electrical resistivity of AA7020 aluminum alloy variants with different Zr and Cr contents. Small changes in the Zr and Cr contents of the as-cast alloy increase the electrical resistivity significantly. After employing various homogenization treatments, the electrical resistivity decreases, which is due to the depletion of Zr, Cr, and Mn in the matrix, by forming small dispersoids. The optimum treatment proposed in order to obtain the smallest recrystallized grains is to hold the material at 550 °C for 24 hours, which results in the lowest electrical resistivity. The viability of the proposed treatment was tested through hot compression tests and static annealing. Indeed, the samples homogenized at 550 °C for 24 hours showed the smallest recrystallized grains compared to those homogenized at other temperatures.

  10. Influence of restorative technique on the biomechanical behavior of endodontically treated maxillary premolars. Part I: fracture resistance and fracture mode.

    PubMed

    Soares, Paulo Vinicius; Santos-Filho, Paulo Cesar Freitas; Martins, Luis Roberto Marcondes; Soares, Carlos Jose

    2008-01-01

    Unresolved controversy exists concerning the preferred cavity design and restorative technique used to restore endodontically treated maxillary premolars to improve their resistance to fracture under occlusal load. The purpose of this study was to evaluate the fracture resistance, stress distribution, and cusp deformation of endodontically treated human maxillary premolars restored with different materials. The study is divided into 2 parts. In Part I, fracture resistance and fracture mode were determined. Seventy noncarious human maxillary premolars were selected and divided into 7 groups (n=10). The control group, ST, consisted of sound unprepared teeth. Teeth in the other 6 groups were endodontically treated and each received 1 of 2 cavity preparation designs: MODd, direct mesio-occlusal-distal preparation; MODi, indirect mesio-occlusal-distal preparation. Teeth were restored with 4 types of material: AM, MODd restored with amalgam; CR, MODd restored with composite resin; LPR, MODi restored with laboratory-processed composite resin; and LGC, MODi restored with leucite-reinforced glass ceramic. The fracture resistance (N) was assessed under compressive load in a universal testing machine. The data were analyzed by 1-way ANOVA and the Tukey HSD test (alpha =.05). Fracture modes were recorded based on the degree of tooth structure involvement and restoration damage. Statistical analysis showed that the ST group presented the highest fracture resistance values. The restored groups showed significantly higher fracture resistance values compared to the nonrestored groups. The groups restored with adhesive techniques (LPR, CR, and LGC) presented significantly higher fracture resistance values than the group restored with the nonadhesive technique (AM) (P<.001). The catastrophic fractures were prevalent in MODd, MODi, AM, and LPR groups, and less severe fractures were found in ST and LGC groups. For the CR group, there was no prevalent fracture mode. Teeth with the

  11. Utilization of a cross-section CAFM to investigate resistive switching behaviors in a Pt/YMnO3/Pt device

    NASA Astrophysics Data System (ADS)

    Wei, Ling; Yin, Y. F.; Zhang, W. F.

    2016-11-01

    Recently, the filament mechanism has been proposed to explain the resistive switching (RS) behaviors of metal/oxide/metal (MOM) devices, which are highly regarded as promising candidates for future non-volatile memory applications. The major technical difficulties in filament investigation lie in its tiny size and ambiguous position, which is always embedded in the interface of a MOM device. As a feature of this work, the conductive path formed in the YMnO3 (YMO)/Pt interface during the RS process was directly observed through cross-section conduct atomic force microscopy (CAFM). By the voltage source 2-wire and the current source 4-wire measurements, the RS properties of the YMO/Pt interface and YMO film were further distinguished and studied in a special Pt/YMO/Pt step sample. Moreover, fitting results based on current-voltage curves exhibit the high resistance state (HRS) and low resistance state (LRS), in accordance with the Schottky emission and Ohm’s law, respectively. The resistances of the HRS increase with the temperature decrease, while those of the LRS demonstrate a reverse trend in the same process, indicating semiconductor and metal characteristics, respectively. Combining the results of energy dispersive spectroscopy, the RS mechanism was attributed to the conductive path in association with the Mn vacancies created in the annealing process.

  12. Metallic and semiconducting resistivity behavior of La{sub 1−x}K{sub x}MnO{sub 3} manganites

    SciTech Connect

    Choudhary, Dinesh Khan, E. Varshney, Dinesh

    2014-04-24

    The electrical conduction in both metallic and semiconducting phase of La{sub 1−x}K{sub x}MnO{sub 3} (x = 0.05, 0.1, 0.15) is investigated. The phonon frequencies are estimated from the ab initio theory with calibrated Hamiltonian for the atomic interaction between a pair such as Mn–O and La/K–O including van der Walls interaction. The classical electron–phonon model of resistivity, i.e., the Bloch–Gruneisen (BG) model consistently retraces the reported metallic resistivity behavior. The paramagnetic semiconducting nature is discussed with thermal activation, small polaron conduction and Mott’s variable range hopping model. The comparison of experimental data appears favorable with the present analysis.

  13. Microstructure Characterization and Corrosion Resistance Behavior of New Cobalt-Free Maraging Steel Produced Through ESR Techniques

    NASA Astrophysics Data System (ADS)

    Seikh, Asiful H.; Halfa, Hossam; Baig, Muneer; Khan, Sohail M. A.

    2017-03-01

    In this study, two different grades (M23 and M29) of cobalt-free low nickel maraging steel have been produced through electroslag remelting (ESR) process. The corrosion resistance of these ESR steels was investigated in 1 M H2SO4 solution using linear potentiodynamic polarization (LPP) and electrochemical impedance spectroscopy (EIS) techniques. The experiments were performed for different immersion time and solution temperature. To evaluate the corrosion resistance of the ESR steels, some significant characterization parameters from LPP and EIS curves were analyzed and compared with that of conventional C250 maraging steel. Irrespective of measurement techniques used, the results show that the corrosion resistance of the ESR steels was higher than the C250 steel. The microstructure of ESR steels was composed of uniform and well-distributed martensite accompanied with little amount of retained austenite in comparison with C250 steel.

  14. Brain kinin B1 receptor is upregulated by the oxidative stress and its activation leads to stereotypic nociceptive behavior in insulin-resistant rats.

    PubMed

    Dias, Jenny Pena; Gariépy, Helaine De Brito; Ongali, Brice; Couture, Réjean

    2015-07-01

    Kinin B1 receptor (B1R) is virtually absent under physiological condition, yet it is highly expressed in models of diabetes mellitus. This study aims at determining: (1) whether B1R is induced in the brain of insulin-resistant rat through the oxidative stress; (2) the consequence of B1R activation on stereotypic nocifensive behavior; (3) the role of downstream putative mediators in B1R-induced behavioral activity. Sprague-Dawley rats were fed with 10% D-glucose in their drinking water or tap water (controls) for 4 or 12 weeks, combined either with a standard chow diet or a diet enriched with α-lipoic acid (1 g/kg feed) for 4 weeks. The distribution and density of brain B1R binding sites were assessed by autoradiography. Behavioral activity evoked by i.c.v. injection of the B1R agonist Sar-[D-Phe(8)]-des-Arg(9)-BK (10 μg) was measured before and after i.c.v. treatments with selective antagonists (10 μg) for kinin B1 (R-715, SSR240612), tachykinin NK1 (RP-67580) and glutamate NMDA (DL-AP5) receptors or with the inhibitor of NOS (L-NNA). Results showed significant increases of B1R binding sites in various brain areas of glucose-fed rats that could be prevented by the diet containing α-lipoic acid. The B1R agonist elicited head scratching, grooming, sniffing, rearing, digging, licking, face washing, wet dog shake, teeth chattering and biting in glucose-fed rats, which were absent after treatment with α-lipoic acid or antagonists/inhibitors. Data suggest that kinin B1R is upregulated by the oxidative stress in the brain of insulin-resistant rats and its activation causes stereotypic nocifensive behavior through the release of substance P, glutamate and NO. Copyright © 2015 Elsevier Inc. All rights reserved.

  15. Effects of siRNA-mediated silencing of myeloid cell leukelia-1 on the biological behaviors and drug resistance of gastric cancer cells

    PubMed Central

    Li, Bo-Pei; Liu, Jin-Lu; Chen, Jun-Qiang; Wang, Zhen; Mao, Yuan-Tian; Chen, Ye-Yang

    2015-01-01

    Objective: This study was to investigate the effects of siRNA mediated silencing of myeloid cell leukelia-1 (Mcl-1) on the biological behaviors and drug resistance of human drug-resistant gastric cancer (GC) cell lines, and to explore the potential mechanisms. Methods: siRNA targeting Mcl-1 mRNA were designed and independently transfected into SGC-7901/VCR and SGC-7901/DDP. Cell proliferation and drug sensitivity were examined by MTT assay. Cell apoptosis and cell cycle were detected by flow cytometry. Cell Invasion and migration abilities were detected by transwell chamber assays. The expressions of drug-resistance-related genes and apoptosis-related proteins were detected by quantitative real-time PCR and Western blot assay, respectively. Results: siRNA effectively inhibited the Mcl-1 expression, lowered the proliferation rate (P<0.05), raised the apoptosis rate (P<0.05), and arrested cells in S-phase (P<0.05). After inhibiting Mcl-1, the cell migration and invasion decreased (P<0.05), the resistance to VCR, DDP and 5-Fu was reversed to different extents (P<0.05), TS mRNA expression increased significantly (P<0.05), MDR1 remained unchanged (P>0.05), but DPD and TOP2A decreased significantly (P<0.05). Following Mcl-1 silencing, Bcl-2 was over-expressed in VCR-siRNA group, but the expressions of Fas and survivin reduced markedly (P<0.05); Bcl-2 and Fas expressions decreased significantly in DDP-siRNA group (P<0.05), but survivin expression remained unchanged. Conclusion: Mcl-1 is implicated in the proliferation, invasion, apoptosis and drug resistance of GC cells, and may be a promising target for the therapy of GC. PMID:26807186

  16. Electric field tuning resistance switching behavior of SrRuO3/Pb(Mg1/3Nb2/3)O3-PbTiO3 heterostructures at various temperatures

    NASA Astrophysics Data System (ADS)

    Zhou, Cai; Wu, Lei; Zhang, Chao; Yao, Jinli; Jiang, Changjun

    2016-10-01

    The resistance switching behavior induced by in-plane read current in SrRuO3/Pb(Mg1/3Nb2/3)O3-PbTiO3 heterostructures is investigated at different temperatures. With decreasing in-plane read current from 10 mA to 0.01 mA, the symmetrical butterfly-like shape of resistance is gradually converted to an antisymmetrical shape at different temperatures, which is resulted from the enhancement of polarization current effect. Specifically, non-volatile resistance behaviors induced by asymmetric bipolar sweeping of electric field and pulsed electric field are achieved at different temperatures. Our results suggests resistance switching behavior dependence of in-plane read current, which is crucial for further application of complex oxide magnetoelectric and spintronic devices.

  17. Mating behavior and reproductive output in insecticide-resistant and -susceptible strains of the maize weevil (Sitophilus zeamais)

    USDA-ARS?s Scientific Manuscript database

    Insecticide resistance is the most broadly recognized and well studied ecological problem resulting from intensive insecticide use, which also provides useful evolutionary models of newly adapted phenotypes to changing environments. Two common assumptions in such population-oriented models are the e...

  18. The pre-onset, transitional, and foot regions in resistance versus temperature behavior in high-T2 cuprates: Inferences regarding maximum T2

    NASA Astrophysics Data System (ADS)

    Vezzoli, G. C.; Burke, T.; Chen, M. F.; Craver, F.; Stanley, W.

    1992-09-01

    We have studied the pre-onset deviation-from-linearity region, the transitional regime, and the foot region in the resistance versus temperature behavior of high-T sub c oxide superconductors, employing time varying magnetic fields and carefully controlled precise temperatures. We have shown that the best value of T sub c can be extrapolated from the magnetic field induced divergence of the resistance versus inverse absolute temperature data as derived from the transitional and/or foot regions. These data are in accord with results from previous Hall effect studies. The pre-onset region however, shows a differing behavior (in R versus 1000/T as a function of B) which we believe links it to an incipient Cooper pairing that suffers a kinetic barrier opposing formation of a full supercurrent. This kinetic dependence is believed to be associated with the lifetime of the mediator particle. This particle is interpreted to be the virtual exciton formed from internal-field induced charge-transfer excitations which transiently neutralize the multivalence cations and establish bound holes on the oxygens.

  19. Observation of ovarian cancer stem cell behavior and investigation of potential mechanisms of drug resistance in three-dimensional cell culture.

    PubMed

    Chen, Junsong; Wang, Jing; Zhang, Yunxia; Chen, Dengyu; Yang, Cuiping; Kai, Cai; Wang, Xiaoying; Shi, Fangfang; Dou, Jun

    2014-08-01

    Cancer cells behave differently in a three-dimensional (3D) cell culture compared with in the conventional two-dimensional (2D) one. Accumulated evidences indicate that the characteristics of cancer stem cells (CSCs) are different from common cancer cells due to their ability to produce tumors and resist chemoradiation. The objective of this work was to observe CSC behavior and investigate the potential mechanisms of CSC drug resistance in 3D versus 2D in vitro environment. We first demonstrated that the CD44(+)CD117(+)cells isolated from the human epithelial ovarian cancer HO8910 cell line have the properties of CSCs that revealed faster growth, larger tumorsphere and stronger survival potential in the hypoxic environment in 3D cell culture as well as more powerful tumorigenicity in a xenograft mice than the HO8910 cells. The CD44(+)CD117(+)CSCs also exhibited high chemoresistance to anticancer drugs when the cells were incubated with 5-fluorouracil, cisplatin and carboplatin, respectively in 3D versus 2D environment. This might be associated with the high expression of ABCG2, ABCB1 and the high expression of MMP-2 and MMP-9 in CD44(+)CD117(+)CSCs. Overall, these results suggest the advantages of using 3D culture model to accurately display CSC behavior in vitro. 3D model may improve the efficacy of screening anticancer drugs for treatment of ovarian CSCs.

  20. Effect of pulsed light treatments on the growth and resistance behavior of Listeria monocytogenes 10403S, Listeria innocua, and Escherichia coli ATCC 25922 in a liquid substrate.

    PubMed

    Uesugi, Aaron R; Hsu, Lillian; Moraru, Carmen I

    2013-03-01

    Pulsed light (PL) treatment can effectively inactivate a large proportion of contaminating bacteria on surfaces and in clear solutions. An important issue that needs to be investigated is whether repeated exposure to PL treatment causes any changes to the growth and resistance behavior of the bacteria surviving the treatment. To test this, three challenge microorganisms were used: Listeria monocytogenes, Listeria innocua, and Escherichia coli. Cells of the challenge bacteria were treated with either low or high PL doses. Survivors of the PL treatment were enumerated, isolated, regrown, and exposed again to PL treatment. PL inactivation curves were generated for the survivors of each exposure cycle (as well as controls) to examine possible differences induced by repeated treatments. Growth curves of L. monocytogenes, L. innocua, and E. coli isolates recovered from exposure to either 1.1 or 10.1 J/cm(2) were not significantly different from the growth curves of untreated cells. Reduction levels of up to 4 and up to 6 log CFU were obtained after exposure to 1.1 and 10.1 J/cm(2), respectively, both for the controls and the repeatedly treated and recovered isolates. These results show that PL did not significantly change the growth kinetics or resistance to PL of the target microorganisms after up to 10 exposures. These findings have significance for the practical application of PL treatment, as they indicate that this technology does not select for microorganisms with increased resistance.

  1. Effect of NO2 and NH3 on the resistive switching behavior of W/Cu x O/Cu devices

    NASA Astrophysics Data System (ADS)

    Nyenke, Chinwe; Dong, Lixin

    2017-10-01

    Cu x O-based devices were fabricated and investigated for the effect of nitrogen dioxide (NO2) and ammonia (NH3) on resistive switching behavior. Bottom copper (Cu) electrodes, copper-rich copper oxide (Cu x O) switching layers, and top tungsten (W) electrodes were sputtered onto two separate substrates to achieve two sets of memristors. Groups of holes ranging in diameter from 300 nm to 2 µm were wet etched into the top memristor layer to expose the Cu x O surface. At room temperatures, one substrate was subjected to 20 ppm of NO2 gas then a second substrate was subjected to 100 ppm of NH3 to measure the effect on memristance. For the first substrate, low and high resistance states demonstrated decreased values while the overall hysteresis gap collapsed after 10 min of exposure to NO2. The second substrate also showed decreases in resistance states but with a widening of the hysteresis gap after exposure to NH3 for 20 min. Recovery of both devices were visible at 25 and 30 min, respectively.

  2. Corrosion Resistance Behavior of Single-Layer Cathodic Arc PVD Nitride-Base Coatings in 1M HCl and 3.5 pct NaCl Solutions

    NASA Astrophysics Data System (ADS)

    Adesina, Akeem Yusuf; Gasem, Zuhair M.; Madhan Kumar, Arumugam

    2017-04-01

    The electrochemical behavior of single-layer TiN, CrN, CrAlN, and TiAlN coatings on 304 stainless steel substrate, deposited using state-of-the-art and industrial size cathodic arc PVD machine, were evaluated in 1M HCl and 3.5 pct NaCl solutions. The corrosion behavior of the blank and coated substrates was analyzed by electrochemical impedance spectroscopy (EIS), linear polarization resistance, and potentiodynamic polarization. Bond-coat layers of pure-Ti, pure-Cr, alloyed-CrAl, and alloyed-TiAl for TiN, CrN, CrAlN, and TiAlN coatings were, respectively, first deposited for improved coating adhesion before the actual coating. The average coating thickness was about 1.80 µm. Results showed that the corrosion potentials ( E corr) of the coated substrates were shifted to more noble values which indicated improvement of the coated substrate resistance to corrosion susceptibility. The corrosion current densities were lower for all coated substrates as compared to the blank substrate. Similarly, EIS parameters showed that these coatings possessed improved resistance to defects and pores in similar solution compared to the same nitride coatings developed by magnetron sputtering. The charge transfer resistance ( R ct) can be ranked in the following order: TiAlN > CrN > TiN > CrAlN in both media except in NaCl solution where R ct of TiN is lowest. While the pore resistance ( R po) followed the order: CrAlN > CrN > TiAlN > TiN in HCl solution and TiAlN > CrN > CrAlN > TiN in NaCl solution. It is found that TiAlN coating has the highest protective efficiencies of 79 and 99 pct in 1M HCl and 3.5 pct NaCl, respectively. SEM analysis of the corroded substrates in both media was also presented.

  3. Corrosion Resistance Behavior of Single-Layer Cathodic Arc PVD Nitride-Base Coatings in 1M HCl and 3.5 pct NaCl Solutions

    NASA Astrophysics Data System (ADS)

    Adesina, Akeem Yusuf; Gasem, Zuhair M.; Madhan Kumar, Arumugam

    2017-01-01

    The electrochemical behavior of single-layer TiN, CrN, CrAlN, and TiAlN coatings on 304 stainless steel substrate, deposited using state-of-the-art and industrial size cathodic arc PVD machine, were evaluated in 1M HCl and 3.5 pct NaCl solutions. The corrosion behavior of the blank and coated substrates was analyzed by electrochemical impedance spectroscopy (EIS), linear polarization resistance, and potentiodynamic polarization. Bond-coat layers of pure-Ti, pure-Cr, alloyed-CrAl, and alloyed-TiAl for TiN, CrN, CrAlN, and TiAlN coatings were, respectively, first deposited for improved coating adhesion before the actual coating. The average coating thickness was about 1.80 µm. Results showed that the corrosion potentials (E corr) of the coated substrates were shifted to more noble values which indicated improvement of the coated substrate resistance to corrosion susceptibility. The corrosion current densities were lower for all coated substrates as compared to the blank substrate. Similarly, EIS parameters showed that these coatings possessed improved resistance to defects and pores in similar solution compared to the same nitride coatings developed by magnetron sputtering. The charge transfer resistance (R ct) can be ranked in the following order: TiAlN > CrN > TiN > CrAlN in both media except in NaCl solution where R ct of TiN is lowest. While the pore resistance (R po) followed the order: CrAlN > CrN > TiAlN > TiN in HCl solution and TiAlN > CrN > CrAlN > TiN in NaCl solution. It is found that TiAlN coating has the highest protective efficiencies of 79 and 99 pct in 1M HCl and 3.5 pct NaCl, respectively. SEM analysis of the corroded substrates in both media was also presented.

  4. Feeding and dispersal behavior of the cotton leafworm, Alabama argillacea (Hübner) (Lepidoptera: Noctuidae), on Bt and non-Bt cotton: implications for evolution and resistance management.

    PubMed

    Ramalho, Francisco S; Pachú, Jéssica K S; Lira, Aline C S; Malaquias, José B; Zanuncio, José C; Fernandes, Francisco S

    2014-01-01

    The host acceptance of neonate Alabama argillacea (Hübner) (Lepidoptera: Noctuidae) larvae to Bt cotton plants exerts a strong influence on the potential risk that this pest will develop resistance to Bt cotton. This will also determine the efficiency of management strategies to prevent its resistance such as the "refuge-in-the-bag" strategy. In this study, we assessed the acceptance of neonate A. argillacea larvae to Bt and non-Bt cotton plants at different temperatures during the first 24 h after hatching. Two cotton cultivars were used in the study, one a Bt DP 404 BG (Bollgard) cultivar, and the other, an untransformed isoline, DP 4049 cultivar. There was a greater acceptance by live neonate A. argillacea larvae for the non-Bt cotton plants compared with the Bt cotton plants, especially in the time interval between 18 and 24 h. The percentages of neonate A. argillacea larvae found on Bt or non-Bt plants were lower when exposed to temperatures of 31 and 34 °C. The low acceptance of A. argillacea larvae for Bt cotton plants at high temperatures stimulated the dispersion of A. argillacea larvae. Our results support the hypothesis that the dispersion and/or feeding behavior of neonate A. argillacea larvae is different between Bt and non-Bt cotton. The presence of the Cry1Ac toxin in Bt cotton plants, and its probable detection by the A. argillacea larvae tasting or eating it, increases the probability of dispersion from the plant where the larvae began. These findings may help to understand how the A. argillacea larvae detect the Cry1Ac toxin in Bt cotton and how the toxin affects the dispersion behavior of the larvae over time. Therefore, our results are extremely important for the management of resistance in populations of A. argillacea on Bt cotton.

  5. Feeding and Dispersal Behavior of the Cotton Leafworm, Alabama argillacea (Hübner) (Lepidoptera: Noctuidae), on Bt and Non-Bt Cotton: Implications for Evolution and Resistance Management

    PubMed Central

    Ramalho, Francisco S.; Pachú, Jéssica K. S.; Lira, Aline C. S.; Malaquias, José B.; Zanuncio, José C.; Fernandes, Francisco S.

    2014-01-01

    The host acceptance of neonate Alabama argillacea (Hübner) (Lepidoptera: Noctuidae) larvae to Bt cotton plants exerts a strong influence on the potential risk that this pest will develop resistance to Bt cotton. This will also determine the efficiency of management strategies to prevent its resistance such as the “refuge-in-the-bag” strategy. In this study, we assessed the acceptance of neonate A. argillacea larvae to Bt and non-Bt cotton plants at different temperatures during the first 24 h after hatching. Two cotton cultivars were used in the study, one a Bt DP 404 BG (Bollgard) cultivar, and the other, an untransformed isoline, DP 4049 cultivar. There was a greater acceptance by live neonate A. argillacea larvae for the non-Bt cotton plants compared with the Bt cotton plants, especially in the time interval between 18 and 24 h. The percentages of neonate A. argillacea larvae found on Bt or non-Bt plants were lower when exposed to temperatures of 31 and 34°C. The low acceptance of A. argillacea larvae for Bt cotton plants at high temperatures stimulated the dispersion of A. argillacea larvae. Our results support the hypothesis that the dispersion and/or feeding behavior of neonate A. argillacea larvae is different between Bt and non-Bt cotton. The presence of the Cry1Ac toxin in Bt cotton plants, and its probable detection by the A. argillacea larvae tasting or eating it, increases the probability of dispersion from the plant where the larvae began. These findings may help to understand how the A. argillacea larvae detect the Cry1Ac toxin in Bt cotton and how the toxin affects the dispersion behavior of the larvae over time. Therefore, our results are extremely important for the management of resistance in populations of A. argillacea on Bt cotton. PMID:25369211

  6. Deletion of GIRK2 Subunit of GIRK Channels Alters the 5-HT1A Receptor-Mediated Signaling and Results in a Depression-Resistant Behavior

    PubMed Central

    Llamosas, Nerea; Bruzos-Cidón, Cristina; Rodríguez, José Julio; Ugedo, Luisa

    2015-01-01

    Background: Targeting dorsal raphe 5-HT1A receptors, which are coupled to G-protein inwardly rectifying potassium (GIRK) channels, has revealed their contribution not only to behavioral and functional aspects of depression but also to the clinical response to its treatment. Although GIRK channels containing GIRK2 subunits play an important role controlling excitability of several brain areas, their impact on the dorsal raphe activity is still unknown. Thus, the goal of the present study was to investigate the involvement of GIRK2 subunit-containing GIRK channels in depression-related behaviors and physiology of serotonergic neurotransmission. Methods: Behavioral, functional, including in vivo extracellular recordings of dorsal raphe neurons, and neurogenesis studies were carried out in wild-type and GIRK2 mutant mice. Results: Deletion of the GIRK2 subunit promoted a depression-resistant phenotype and determined the behavioral response to the antidepressant citalopram without altering hippocampal neurogenesis. In dorsal raphe neurons of GIRK2 knockout mice, and also using GIRK channel blocker tertiapin-Q, the basal firing rate was higher than that obtained in wild-type animals, although no differences were observed in other firing parameters. 5-HT1A receptors were desensitized in GIRK2 knockout mice, as demonstrated by a lower sensitivity of dorsal raphe neurons to the inhibitory effect of the 5-HT1A receptor agonist, 8-OH-DPAT, and the antidepressant citalopram. Conclusions: Our results indicate that GIRK channels formed by GIRK2 subunits determine depression-related behaviors as well as basal and 5-HT1A receptor-mediated dorsal raphe neuronal activity, becoming alternative therapeutic targets for psychiatric diseases underlying dysfunctional serotonin transmission. PMID:25956878

  7. Impact of Treatments for Depression on Comorbid Anxiety, Attentional, and Behavioral Symptoms in Adolescents With Selective Serotonin Reuptake Inhibitor–Resistant Depression

    PubMed Central

    Hilton, Robert C.; Rengasamy, Manivel; Mansoor, Brandon; He, Jiayan; Mayes, Taryn; Emslie, Graham J.; Porta, Giovanna; Clarke, Greg N.; Wagner, Karen Dineen; Birmaher, Boris; Keller, Martin B.; Ryan, Neal; Shamseddeen, Wael; Asarnow, Joan Rosenbaum; Brent, David A.

    2013-01-01

    Objective To assess the relative efficacy of antidepressant medication, alone and in combination with cognitive behavioral therapy (CBT), on comorbid symptoms of anxiety, attention, and disruptive behavior disorders in participants in the Treatment of Resistant Depression in Adolescents (TORDIA) trial. Method Adolescents with selective serotonin reuptake inhibitor (SSRI)–resistant depression (N = 334) were randomly assigned to a medication switch alone (to another SSRI or to venlafaxine) or to a medication switch plus CBT. Anxiety, attention-deficit/hyperactivity disorder (ADHD), and disruptive behavior disorder (DBD) symptoms were assessed by psychiatric interview and self-report at regular intervals between baseline and 24 weeks. The differential effects of medication and of CBT, and the impact of remission on the course of comorbid symptoms and diagnoses, were assessed using generalized linear mixed models. Results Remission was associated with a greater reduction in scalar measures of anxiety, ADHD, and DBDs, and a greater decrease in the rate of diagnosed anxiety disorders. The correlations between the changes in symptoms of depression on the CDRS-R and anxiety, ADHD, and oppositional symptoms were modest, ranging from r = 0.12 to r = 0.28. There were no significant differential treatment effects on diagnoses, or corresponding symptoms. Conclusion The achievement of remission had a beneficial effect on anxiety, ADHD, and DBD symptoms, regardless of the type of treatment received. There were no differential effects of medication or CBT on outcome, except for a nonsignificant trend that those adolescents treated with SSRIs showed a greater decrease in rates of comorbid DBDs relative to those treated with venlafaxine. PMID:23622849

  8. Resistant starch film-coated microparticles for an oral colon-specific polypeptide delivery system and its release behaviors.

    PubMed

    Situ, Wenbei; Chen, Ling; Wang, Xueyu; Li, Xiaoxi

    2014-04-23

    For the delivery of bioactive components to the colon, an oral colon-specific controlled release system coated with a resistant starch-based film through aqueous dispersion coating process was developed. Starch was modified by a high-temperature-pressure reaction, enzymatic debranching, and retrogradation, resulting in a dramatic increase in the resistibility against enzymatic digestion (meaning the formation of resistant starch, specifically RS3). This increase could be associated with an increase in the relative crystallinity, a greater amount of starch molecular aggregation structure, and the formation of a compact mass fractal structure, resulting from the treatment. The microparticles coated with this RS3 film showed an excellent controlled release property. In streptozotocin (STZ)-induced type II diabetic rats, the RS3 film-coated insulin-loaded microparticles exhibited the ability to steadily decrease the plasma glucose level initially and then maintain the plasma glucose level within the normal range for total 14-22 h with different insulin dosages after oral administration; no glycopenia or glycemic fluctuation was observed. Therefore, the potential of this new RS3 film-coated microparticle system has been demonstrated for the accurate delivery of bioactive polypeptides or protein to the colon.

  9. The R-curve behavior and thermal shock resistance for Al2O3 + ZrO2 laminated nanoceramics.

    PubMed

    Chen, Bei; Hu, Xiaohua; Cheng, Chuan

    2014-05-01

    The properties of thermal shock resistances of Al2O3 + ZrO2 monolayer and laminated ceramics are determined by the indentation method. The relationships between the R-curve, the thermal shock resistance properties and the mechanism of strengthening and toughening are also studied in this paper. The Al2O3 + ZrO2 laminated ceramics have an R-curve feature and a decrease in the sensitivity of the strength to the size of surface cracks. Indentation thermal shock test shows that the critical temperature difference of the Al2O3 + ZrO2 laminated ceramics is 400 degrees C, 150 degrees C higher than that of the monolayer ceramics. Under the condition of the surface compressive stress, the surface fracture appearance is more uneven and the fracture mechanism is different along the interface. The R-curve and thermal shock resistance properties are improved by strengthening the transformation effect resulting from the surface compressive stress.

  10. Resistance to protein and oil fouling of sulfobetaine-grafted Poly(vinylidene Fluoride) hollow fiber membrane and the electrolyte-responsive behavior in NaCl solution

    NASA Astrophysics Data System (ADS)

    Li, Qian; Bi, Qiu-Yan; Liu, Tian-Yin; Wang, Xiao-Lin

    2012-07-01

    An excellent protein-fouling-resistance performance of the sulfobetaine-grafted PVDF hollow fiber membrane was obtained and the potential of sulfobetaine-grafted PVDF membrane to resist the oil fouling was confirmed in the filtration solution which contained inorganic electrolyte, sodium chloride (NaCl). The electrolyte-responsive behavior of the sulfobetaine-modified PVDF membrane was demonstrated by the filtration of NaCl aqueous solution. The grafting amount of the modified PVDF hollow fiber membrane showed a stable value as 680 μg/cm2. An almost complete coverage of the membrane surface by the grafted sulfobetaine polymer contributed to the high hydrophilicity and membrane strength. The membrane surface became denser and the permeate flux reduced with the increase of NaCl concentration. The cyclic filtration experiment showed that during the filtration of the protein solution with 0.05 mol/L of NaCl, the sulfobetaine-grafted PVDF membrane exhibited an excellent protein-fouling-resistance performance with a high relative flux recovery of 98.2% and a low irreversible fouling extent which was lower 10 times than that of the nascent PVDF hollow fiber membrane. In addition, the sulfobetaine-grafted PVDF hollow fiber membrane showed an oil-fouling-resistance property during the filtration experiment of the oil-in-water emulsion with 0.05 mol/L of NaCl, resulting in an relative flux recovery of about twice that of the nascent PVDF membrane. The results extended the application of poly(sulfobetaine)-g-PVDF hollow fiber membrane in the fields of bio-separation, artificial oil and wastewater treatment.

  11. Questionnaires for outcome expectancy, self-regulation, and behavioral expectation for resistance training among young-old adults: development and preliminary validity.

    PubMed

    Williams, David M; Savla, Jyoti; Davy, Brenda M; Kelleher, Sarah A; Marinik, Elaina L; Winett, Richard A

    2015-04-01

    The purpose of the present research was to develop questionnaires to assess outcome expectancy for resistance training (RT), behavioral expectation in the context of perceived barriers to RT, and self-regulation strategies for RT among young-old adults (50-69 years). Measurement development included (a) item generation through elicitation interviews (N = 14) and open-ended questionnaires (N = 56), (b) expert feedback on a preliminary draft of the questionnaires (N = 4), and (c) a quantitative longitudinal study for item-reduction and psychometric analyses (N = 94). Elicitation procedures, expert feedback, and item reduction yielded four questionnaires with a total of 33 items. Positive outcome expectancy (α = .809), negative outcome expectancy (α = .729), behavioral expectation (α = .925), and self-regulation (α = .761) had-with one exception-moderate bivariate associations with two different indicators of self-reported RT behavior at one-month follow-up (r = .298 to .506). The present research provides preliminary support for newly developed questionnaires to facilitate understanding of the psychosocial determinants of RT among young-old adults.

  12. Phase Transformation Behavior and Resistance to Bending and Cyclic Fatigue of ProTaper Gold and ProTaper Universal Instruments.

    PubMed

    Hieawy, Ahmed; Haapasalo, Markus; Zhou, Huimin; Wang, Zhe-Jun; Shen, Ya

    2015-07-01

    The purpose of this study was to compare the flexibility and cyclic fatigue resistance of ProTaper Universal (PTU; Dentsply Tulsa Dental Specialities, Tulsa, OK) and ProTaper Gold (PTG; Dentsply Tulsa Dental Specialities, Tulsa, OK) instruments in relation to their phase transformation behavior. Sizes S1, S2, F1, F2, and F3 of PTU and PTG instruments were subjected to rotational bending at a curvature of 40° and a radius of 6 mm. The number of cycles to fracture (NCF) was recorded. The fracture surface of all fragments was examined with a scanning electron microscope. Flexibility was determined by 45° bending tests according to the ISO 3630-1 specification. Unused and fractured instruments were examined by differential scanning calorimetry. PTG had a cyclic fatigue resistance superior to PTU in all sizes (P < .001). The NCF of the nickel-titanium files of sizes S1 and S2 was significantly higher than those of sizes F1 to F3 (P < .001). No significant difference in the NCF of PTU instruments was detected between F1 and F2. The fractured files of both PTU and PTG showed the typical fracture pattern of fatigue failure. The bending load values were significantly lower for PTG than for PTU (P < .05). The differential scanning calorimetry analyses showed that each segment of the PTG instruments had a higher austenite finish temperature (50.1°C ± 1.7°C) than the PTU instruments (21.2°C ± 1.9°C) (P < .001). PTG instruments had a 2-stage transformation behavior. There was no significant difference in the austenite finish between unused files and instruments subjected to the fatigue process. PTG files were significantly more flexible and resistant to fatigue than PTU files. PTG exhibited different phase transformation behavior than PTU, which may be attributed to the special heat treatment history of PTG instruments. PTG may be more suited for preparing canals with a more abrupt curvature. Copyright © 2015 American Association of Endodontists. Published by Elsevier

  13. Impact of composition and crystallization behavior of atomic layer deposited strontium titanate films on the resistive switching of Pt/STO/TiN devices

    SciTech Connect

    Aslam, N.; Rodenbücher, C.; Szot, K.; Waser, R.; Hoffmann-Eifert, S.; Longo, V.; Roozeboom, F.; Kessels, W. M. M.

    2014-08-14

    The resistive switching (RS) properties of strontium titanate (Sr{sub 1+x}Ti{sub 1+y}O{sub 3+(x+2y)}, STO) based metal-oxide-metal structures prepared from industrial compatible processes have been investigated focusing on the effects of composition, microstructure, and device size. Metastable perovskite STO films were prepared on Pt-coated Si substrates utilizing plasma-assisted atomic layer deposition (ALD) from cyclopentadienyl-based metal precursors and oxygen plasma at 350 °C, and a subsequent annealing at 600 °C in nitrogen. Films of 15 nm and 12 nm thickness with three different compositions [Sr]/([Sr] + [Ti]) of 0.57 (Sr-rich STO), 0.50 (stoichiometric STO), and 0.46 (Ti-rich STO) were integrated into Pt/STO/TiN crossbar structures with sizes ranging from 100 μm{sup 2} to 0.01 μm{sup 2}. Nano-structural characterizations revealed a clear effect of the composition of the as-deposited STO films on their crystallization behavior and thus on the final microstructures. Local current maps obtained by local-conductivity atomic force microscopy were in good agreement with local changes of the films' microstructures. Correspondingly, also the initial leakage currents of the Pt/STO/TiN devices were affected by the STO compositions and by the films' microstructures. An electroforming process set the Pt/STO/TiN devices into the ON-state, while the forming voltage decreased with increasing initial leakage current. After a RESET process under opposite voltage has been performed, the Pt/STO/TiN devices showed a stable bipolar RS behavior with non-linear current-voltage characteristics for the high (HRS) and the low (LRS) resistance states. The obtained switching polarity and nearly area independent LRS values agree with a filamentary character of the RS behavior according to the valence change mechanism. The devices of 0.01 μm{sup 2} size with a 12 nm polycrystalline stoichiometric STO film were switched at a current compliance of 50 μA with

  14. Efficient spin-filter and negative differential resistance behaviors in FeN{sub 4} embedded graphene nanoribbon device

    SciTech Connect

    Liu, N. Liu, J. B.; Yao, K. L.; Ni, Y.; Wang, S. L.

    2016-03-14

    In this paper, we propose a new device of spintronics by embedding two FeN{sub 4} molecules into armchair graphene nanoribbon and sandwiching them between N-doped graphene nanoribbon electrodes. Our first-principle quantum transport calculations show that the device is a perfect spin filter with high spin-polarizations both in parallel configuration (PC) and antiparallel configuration (APC). Moreover, negative differential resistance phenomena are obtained for the spin-down current in PC, and the spin-up and spin-down currents in APC. These transport properties are explained by the bias-dependent evolution of molecular orbitals and the transmission spectra.

  15. Efficient spin-filter and negative differential resistance behaviors in FeN4 embedded graphene nanoribbon device

    NASA Astrophysics Data System (ADS)

    Liu, N.; Liu, J. B.; Yao, K. L.; Ni, Y.; Wang, S. L.

    2016-03-01

    In this paper, we propose a new device of spintronics by embedding two FeN4 molecules into armchair graphene nanoribbon and sandwiching them between N-doped graphene nanoribbon electrodes. Our first-principle quantum transport calculations show that the device is a perfect spin filter with high spin-polarizations both in parallel configuration (PC) and antiparallel configuration (APC). Moreover, negative differential resistance phenomena are obtained for the spin-down current in PC, and the spin-up and spin-down currents in APC. These transport properties are explained by the bias-dependent evolution of molecular orbitals and the transmission spectra.

  16. Multi-level resistive switching behaviors and retention characteristics in ZnO/Nb:SrTiO3 heterojunction

    NASA Astrophysics Data System (ADS)

    Ren, Yong; Li, Jiachen; Zhang, Weifeng; Jia, Caihong

    2017-10-01

    Epitaxial ZnO thin films were grown on SrTiO3:Nb (NSTO) substrates by rf magnetron sputtering method. The multi-level resistance states were observed by applying different amplitudes and/or polarities of voltage pulses, which is supposed to be related to the drift of oxygen vacancies. Furthermore, the decay of retention is also corresponding to the migration of oxygen vacancies. The retention and cycle stability implies that the ZnO/Nb:SrTiO3 heterojunctions are promising for high density memory application.

  17. Development of Behavioral Control and Associated vmPFC-DLPFC Connectivity Explains Children's Increased Resistance to Temptation in Intertemporal Choice.

    PubMed

    Steinbeis, Nikolaus; Haushofer, Johannes; Fehr, Ernst; Singer, Tania

    2016-01-01

    Human civilization is based on the successful pursuit of long-term goals, requiring the ability to forego immediate pleasure for the sake of larger future rewards. This ability improves with age, but the precise cognitive and neural mechanisms underlying its development remain elusive. The developmental changes could result either from younger children valuing immediate rewards more strongly or because older children become better at controlling their impulses. By implementing 2 tasks, a choice-independent valuation task and an intertemporal choice task, both behaviorally and using fMRI in twenty 6- to 13-year old children, we show developmental improvements in behavioral control to uniquely account for age-related changes in temporal discounting. We show further that overcoming temptation during childhood occurs as a function of an age-related increase in functional coupling between value signals in the ventromedial prefrontal cortex and brain regions dedicated to behavioral control, such as left dorsolateral prefrontal cortex during choice. These findings can help to devise measures that reduce the substantial costs of impatience to society. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  18. Feeding behavior of neonate Ostrinia nubilalis (Lepidoptera: Crambidae) on Cry1Ab Bt corn: implications for resistance management.

    PubMed

    Razze, J M; Mason, C E; Pizzolato, T D

    2011-06-01

    The European corn borer, Ostrinia nubilalis (Hübner) (Lepidoptera: Crambidae), is an economically important insect pest of corn, Zea mays L., in the United States and Canada. The development of genetically modified corn expressing genes derived from Bacillus thuringiensis (Bt) that encodes insecticidal crystalline (Cry) proteins has proven to be effective in controlling this insect. To assess the feeding behavior of neonate O. nubilalis on Bt corn, we examined differences in feeding behavior, based on presence of plant material in the gut, between Cry1Ab Bt corn and non-Bt near isoline corn for four intervals over a 48-h period. Feeding experiments revealed that there was significantly less feeding on Bt corn compared with non-Bt near isoline corn. The behavior of neonates on the plant corresponded with the differences in feeding on the two corn lines. The findings also showed that > 50% of the larvae initially left the plant before there was evidence in the gut of feeding regardless of whether the source was Bt or non-Bt corn. A higher quantity of plant material was found in the gut of larvae recovered from leaves of non-Bt compared with Bt corn. At the end of 48 h among the larvae that had left the plant, a greater proportion from Bt corn had plant material in the gut than did those from non-Bt corn.

  19. Coarsening behavior of MX carbonitrides in type 347H heat-resistant austenitic steel during thermal aging

    NASA Astrophysics Data System (ADS)

    Zhou, Ying-hui; Liu, Chen-xi; Liu, Yong-chang; Guo, Qian-ying; Li, Hui-jun

    2016-03-01

    In this work, the growth kinetics of MX (M = metal, X = C/N) nanoprecipitates in type 347H austenitic steel was systematically studied. To investigate the coarsening behavior and the growth mechanism of MX carbonitrides during long-term aging, experiments were performed at 700, 800, 850, and 900°C for different periods (1, 24, 70, and 100 h). The precipitation behavior of carbonitrides in specimens subjected to various aging conditions was explored using carbon replicas and transmission electron microscopy (TEM) observations. The corresponding sizes of MX carbonitrides were measured. The results demonstrates that MX carbonitrides precipitate in type 347H austenitic steel as Nb(C,N). The coarsening rate constant is time-independent; however, an increase in aging temperature results in an increase in coarsening rate of Nb(C,N). The coarsening process was analyzed according to the calculated diffusion activation energy of Nb(C,N). When the aging temperature was 800-900°C, the mean activation energy was 294 kJ·mol-1, and the coarsening behavior was controlled primarily by the diffusion of Nb atoms.

  20. Fermi liquid behavior of the in-plane resistivity in the pseudogap state of YBa2Cu4O8

    NASA Astrophysics Data System (ADS)

    Proust, Cyril; Vignolle, Baptiste; Levallois, Julien; Adachi, S.; Hussey, Nigel E.

    2016-11-01

    Our knowledge of the ground state of underdoped hole-doped cuprates has evolved considerably over the last few years. There is now compelling evidence that, inside the pseudogap phase, charge order breaks translational symmetry leading to a reconstructed Fermi surface made of small pockets. Quantum oscillations [Doiron-Leyraud N, et al. (2007) Nature 447(7144):565-568], optical conductivity [Mirzaei SI, et al. (2013) Proc Natl Acad Sci USA 110(15):5774-5778], and the validity of Wiedemann-Franz law [Grissonnache G, et al. (2016) Phys Rev B 93:064513] point to a Fermi liquid regime at low temperature in the underdoped regime. However, the observation of a quadratic temperature dependence in the electrical resistivity at low temperatures, the hallmark of a Fermi liquid regime, is still missing. Here, we report magnetoresistance measurements in the magnetic-field-induced normal state of underdoped YBa2Cu4O8 that are consistent with a T2 resistivity extending down to 1.5 K. The magnitude of the T2 coefficient, however, is much smaller than expected for a single pocket of the mass and size observed in quantum oscillations, implying that the reconstructed Fermi surface must consist of at least one additional pocket.

  1. Cooking behavior and starch digestibility of NUTRIOSE® (resistant starch) enriched noodles from sweet potato flour and starch.

    PubMed

    Menon, Renjusha; Padmaja, G; Sajeev, M S

    2015-09-01

    The effect of a resistant starch source, NUTRIOSE® FB06 at 10%, 15% and 20% in sweet potato flour (SPF) and 5% and 10% in sweet potato starch (SPS) in reducing the starch digestibility and glycaemic index of noodles was investigated. While NUTRIOSE (10%) significantly reduced the cooking loss in SPF noodles, this was enhanced in SPS noodles and guar gum (GG) supplementation reduced CL of both noodles. In vitro starch digestibility (IVSD) was significantly reduced in test noodles compared to 73.6g glucose/100g starch in control SPF and 65.9 g in SPS noodles. Resistant starch (RS) was 54.96% for NUTRIOSE (15%)+GG (1%) fortified SPF noodles and 53.3% for NUTRIOSE (5%)+GG (0.5%) fortified SPS noodles, as against 33.8% and 40.68%, respectively in SPF and SPS controls. Lowest glycaemic index (54.58) and the highest sensory scores (4.23) were obtained for noodles with 15% NUTRIOSE+1% GG.

  2. Antibacterial activity, corrosion resistance and wear behavior of spark plasma sintered Ta-5Cu alloy for biomedical applications.

    PubMed

    Cui, Jing; Zhao, Liang; Zhu, Weiwei; Wang, Bi; Zhao, Cancan; Fang, Liming; Ren, Fuzeng

    2017-10-01

    Tantalum has been widely used in orthopedic and dental implants. However, the major barrier to the extended use of such medical devices is the possibility of bacterial adhesion to the implant surface which will cause implant-associated infections. To solve this problem, bulk Ta-5Cu alloy has been fabricated by a combination of mechanical alloying and spark plasma sintering. The effect of the addition of Cu on the hardness, antibacterial activity, cytocompatibility, corrosion resistance and wear performance was systematically investigated. The sintered Ta-5Cu alloy shows enhanced antibacterial activity against E. Coli due to the sustained release of Cu ions. However, the addition of Cu would produce slight cytotoxicity and decrease corrosion resistance of Ta. Furthermore, pin-on-disk wear tests show that Ta-5Cu alloy has a much lower coefficient of friction but a higher wear rate and shows a distinct wear mode from that of Ta upon sliding against stainless steel 440C. Wear-induced plastic deformation leads to elongation of Ta and Cu grains along the sliding direction and nanolayered structures were observed upon approaching the sliding surface. The presence of hard oxides also shows a profound effect on the plastic flow of the base material and results in localized vortex patterns. The obtained results are expected to provide deep insights into the development of novel Ta-Cu alloy for biomedical applications. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Oxidation resistance and compressive creep behavior of boron doped Mo{sub 5}Si{sub 3}

    SciTech Connect

    Meyer, M.K.; Akinc, M. |; Kramer, M.J.

    1995-10-01

    Use of Mo{sub 5}Si{sub 3} in high temperature applications is limited by oxidation induced catastrophic failure above 800 C. Oxidation resistance of Mo{sub 5}Si{sub 3} is substantially improved from 800--1,300 C by the addition of boron. The oxidation rate at 1,200 C was decreased by five orders of magnitude with less than 2 weight percent boron addition. The improvement in oxidation resistance of B doped Mo{sub 5}Si{sub 3} is due to formation of a protective scale layer due to viscous flow. The compressive creep rate of B doped Mo{sub 5}Si{sub 3} was measured at various temperature/stress levels and found to be similar to that of the undoped material. The creep rate of B doped Mo{sub 5}Si{sub 3} was measured as 1.8 {times} 10{sup {minus}7} s{sup {minus}1} at 1,242 C and 138 MPa. Creep tests were conducted at 140--180 MPa and 1,220--1,320 C. Average creep activation energy and stress exponent in this range were found to be E{sub a} {approx} 400 kJ/mol and n = 4.3 respectively.

  4. Fermi liquid behavior of the in-plane resistivity in the pseudogap state of YBa2Cu4O8.

    PubMed

    Proust, Cyril; Vignolle, Baptiste; Levallois, Julien; Adachi, S; Hussey, Nigel E

    2016-11-29

    Our knowledge of the ground state of underdoped hole-doped cuprates has evolved considerably over the last few years. There is now compelling evidence that, inside the pseudogap phase, charge order breaks translational symmetry leading to a reconstructed Fermi surface made of small pockets. Quantum oscillations [Doiron-Leyraud N, et al. (2007) Nature 447(7144):565-568], optical conductivity [Mirzaei SI, et al. (2013) Proc Natl Acad Sci USA 110(15):5774-5778], and the validity of Wiedemann-Franz law [Grissonnache G, et al. (2016) Phys Rev B 93:064513] point to a Fermi liquid regime at low temperature in the underdoped regime. However, the observation of a quadratic temperature dependence in the electrical resistivity at low temperatures, the hallmark of a Fermi liquid regime, is still missing. Here, we report magnetoresistance measurements in the magnetic-field-induced normal state of underdoped YBa2Cu4O8 that are consistent with a T(2) resistivity extending down to 1.5 K. The magnitude of the T(2) coefficient, however, is much smaller than expected for a single pocket of the mass and size observed in quantum oscillations, implying that the reconstructed Fermi surface must consist of at least one additional pocket.

  5. Fermi liquid behavior of the in-plane resistivity in the pseudogap state of YBa2Cu4O8

    PubMed Central

    Proust, Cyril; Vignolle, Baptiste; Levallois, Julien; Adachi, S.; Hussey, Nigel E.

    2016-01-01

    Our knowledge of the ground state of underdoped hole-doped cuprates has evolved considerably over the last few years. There is now compelling evidence that, inside the pseudogap phase, charge order breaks translational symmetry leading to a reconstructed Fermi surface made of small pockets. Quantum oscillations [Doiron-Leyraud N, et al. (2007) Nature 447(7144):565–568], optical conductivity [Mirzaei SI, et al. (2013) Proc Natl Acad Sci USA 110(15):5774–5778], and the validity of Wiedemann–Franz law [Grissonnache G, et al. (2016) Phys Rev B 93:064513] point to a Fermi liquid regime at low temperature in the underdoped regime. However, the observation of a quadratic temperature dependence in the electrical resistivity at low temperatures, the hallmark of a Fermi liquid regime, is still missing. Here, we report magnetoresistance measurements in the magnetic-field–induced normal state of underdoped YBa2Cu4O8 that are consistent with a T2 resistivity extending down to 1.5 K. The magnitude of the T2 coefficient, however, is much smaller than expected for a single pocket of the mass and size observed in quantum oscillations, implying that the reconstructed Fermi surface must consist of at least one additional pocket. PMID:27856753

  6. Creep Behavior at 1273 K (1000 °C) in Nb-Bearing Austenitic Heat-Resistant Cast Steels Developed for Exhaust Component Applications

    NASA Astrophysics Data System (ADS)

    Zhang, Yinhui; Li, Mei; Godlewski, Larry A.; Zindel, Jacob W.; Feng, Qiang

    2016-07-01

    A series of Nb-bearing austenitic heat-resistant cast steels with variations of N/C ratios were investigated, and the morphological change of Nb(C,N) from faceted blocks, mixed flake-blocks to "Chinese-script" was observed as N/C ratios decreased. The creep behavior of these alloys was studied at 1273 K (1000 °C), and the longest creep life and lowest creep rate occurred in model alloys with script Nb(C,N). Residual δ-ferrites and (Cr,Fe)23C6 were adverse to creep properties. This work indicates that the control of N/C ratio is required for the as-cast microstructural strengthening.

  7. Autistic behavior, behavior analysis, and the gene

    PubMed Central

    Malott, Richard W.

    2004-01-01

    This article addresses the meaning of autism, the etiology of autistic behavior and values, the nature-nurture debate, contingencies vs. genes, and resistance to a behavioral analysis of autism. PMID:22477285

  8. Non-Fermi Liquid Behavior and Continuously Tunable Resistivity Exponents in the Anderson-Hubbard Model at Finite Temperature

    NASA Astrophysics Data System (ADS)

    Patel, Niravkumar D.; Mukherjee, Anamitra; Kaushal, Nitin; Moreo, Adriana; Dagotto, Elbio

    2017-08-01

    We employ a recently developed computational many-body technique to study for the first time the half-filled Anderson-Hubbard model at finite temperature and arbitrary correlation U and disorder V strengths. Interestingly, the narrow zero temperature metallic range induced by disorder from the Mott insulator expands with increasing temperature in a manner resembling a quantum critical point. Our study of the resistivity temperature scaling Tα for this metal reveals non-Fermi liquid characteristics. Moreover, a continuous dependence of α on U and V from linear to nearly quadratic is observed. We argue that these exotic results arise from a systematic change with U and V of the "effective" disorder, a combination of quenched disorder and intrinsic localized spins.

  9. Assessment of End-of-Life Behavior of the Surface Modification to Improve Cavitation-Erosion Resistance in the Mercury Target at the Spallation Neutron Source

    SciTech Connect

    Pawel, Steven J

    2007-06-01

    The cavitation-erosion resistance of the Kolsterised{reg_sign} layer on annealed or cold-worked substrates of 316LN stainless steel has been examined in mercury using a vibratory horn technique and extended exposure periods intended to expose 'end-of-life' performance characteristics. The Kolsterised{reg_sign} layer tends to remain protective--as evidenced by modest steady-state weight loss and surface roughness increases, only isolated pitting, and limited wetting by mercury--until the protective layer has been thinned by general erosion to about 15-20 {micro}m. Prior to that amount of erosion, the cavitation-erosion resistance of both types of specimens appears defined by the properties of the protective layer. However, after thinning to such a degree, initial breakdown of the protective layer is characterized by increases in both the surface roughness and the number/depth of individual pits across the surface at a rate that is strongly dependent on the substrate condition, with annealed substrates significantly more prone to damage. However, even as the protective properties of the Kolsterised{reg_sign} layer decrease, both weight change and profile development as a function of sonication time suggest a gradual reversion to cavitation-erosion behavior similar to that of untreated substrates.

  10. Effects of N/C Ratio on Solidification Behaviors of Novel Nb-Bearing Austenitic Heat-Resistant Cast Steels for Exhaust Components of Gasoline Engines

    NASA Astrophysics Data System (ADS)

    Zhang, Yinhui; Li, Mei; Godlewski, Larry A.; Zindel, Jacob W.; Feng, Qiang

    2017-03-01

    In order to comply with more stringent environmental and fuel consumption regulations, novel Nb-bearing austenitic heat-resistant cast steels that withstand exhaust temperatures as high as 1,323 K (1,050 °C) is urgently demanded from automotive industries. In the current research, the solidification behavior of these alloys with variations of N/C ratio is investigated. Directional solidification methods were carried out to examine the microstructural development in mushy zones. Computational thermodynamic calculations under partial equilibrium conditions were performed to predict the solidification sequence of different phases. Microstructural characterization of the mushy zones indicates that N/C ratio significantly influenced the stability of γ-austenite and the precipitation temperature of NbC/Nb(C,N), thereby altering the solidification path, as well as the morphology and distribution of NbC/Nb(C,N) and γ-ferrite. The solidification sequence of different phases predicted by thermodynamic software agreed well with the experimental results, except the specific precipitation temperatures. The generated data and fundamental understanding will be helpful for the application of computational thermodynamic methods to predict the as-cast microstructure of Nb-bearing austenitic heat-resistant steels.

  11. Overcoming treatment resistance in chronic depression: a pilot study on outcome and feasibility of the cognitive behavioral analysis system of psychotherapy as an inpatient treatment program.

    PubMed

    Brakemeier, Eva-Lotta; Radtke, Martina; Engel, Vera; Zimmermann, Johannes; Tuschen-Caffier, Brunna; Hautzinger, Martin; Schramm, Elisabeth; Berger, Mathias; Normann, Claus

    2015-01-01

    The Cognitive Behavioral Analysis System of Psychotherapy (CBASP), initially developed as an outpatient treatment for chronic depression (CD), has been adapted as a multidisciplinary 12-week inpatient program for CD. Seventy inpatients with CD and treatment resistance were included in a noncontrolled trial. The Hamilton Depression Rating Scale served as the primary outcome measure. Prospective naturalistic follow-up assessments were conducted 6 and 12 months after discharge. Dropout rate was 7.1%; 90.4% perceived the program as helpful. Pre-post comparisons yielded strong effect sizes; 75.7% of the intention-to-treat sample responded, and 40.0% remitted. Nonremission was associated with experiencing temporary deterioration of symptoms during treatment. After 6 months 75.0% and after 12 months 48.0% of patients sustained response. The CBASP program appears as a feasible acute treatment for treatment-resistant CD inpatients with promising outcome. However, the continuation of treatment after discharge should be optimized especially for patients with subjective deterioration during treatment.

  12. Effects of N/C Ratio on Solidification Behaviors of Novel Nb-Bearing Austenitic Heat-Resistant Cast Steels for Exhaust Components of Gasoline Engines

    NASA Astrophysics Data System (ADS)

    Zhang, Yinhui; Li, Mei; Godlewski, Larry A.; Zindel, Jacob W.; Feng, Qiang

    2017-01-01

    In order to comply with more stringent environmental and fuel consumption regulations, novel Nb-bearing austenitic heat-resistant cast steels that withstand exhaust temperatures as high as 1,323 K (1,050 °C) is urgently demanded from automotive industries. In the current research, the solidification behavior of these alloys with variations of N/C ratio is investigated. Directional solidification methods were carried out to examine the microstructural development in mushy zones. Computational thermodynamic calculations under partial equilibrium conditions were performed to predict the solidification sequence of different phases. Microstructural characterization of the mushy zones indicates that N/C ratio significantly influenced the stability of γ-austenite and the precipitation temperature of NbC/Nb(C,N), thereby altering the solidification path, as well as the morphology and distribution of NbC/Nb(C,N) and γ-ferrite. The solidification sequence of different phases predicted by thermodynamic software agreed well with the experimental results, except the specific precipitation temperatures. The generated data and fundamental understanding will be helpful for the application of computational thermodynamic methods to predict the as-cast microstructure of Nb-bearing austenitic heat-resistant steels.

  13. Silicon carbide as an oxidation-resistant high-temperature material. 1: Oxidation and heat corrosion behavior

    NASA Technical Reports Server (NTRS)

    Schlichting, J.

    1981-01-01

    The oxidation and corrosion behavior of SiC (in the form of a SiC powder) and hot-pressed and reaction-bound material were studied. The excellent stability of SiC in an oxidizing atmosphere is due to the development of protective SiO2 coatings. Any changes in these protective layers (e.g., due to impurities, reaction with corrosive media, high porosity of SiC, etc.) lead in most cases to increased rates of oxidation and thus restrict the field of SiC application.

  14. Comparing the behavior of multidrug-resistant and pansusceptible Salmonella during the production and aging of a Gouda cheese manufactured from raw milk.

    PubMed

    D'Amico, Dennis J; Druart, Marc J; Donnelly, Catherine W

    2014-06-01

    Outbreaks of salmonellosis have been linked to the consumption of cheese, and emerging multidrug-resistant (MDR) strains of Salmonella may be more virulent and more tolerant than less resistant strains to stresses encountered in food production, which may enhance the survival of these resistant strains in cheese. This study was conducted to compare the behavior of MDR and pansusceptible Salmonella strains during the manufacture and aging of Gouda cheese and compare pathogen recovery via several rapid and traditional methods. Cheeses were manufactured from raw milk inoculated with a six-strain cocktail of either MDR or susceptible Salmonella Newport and Salmonella Typhimurium at initial levels of <20 CFU/ml. Samples of milk, whey, curd, and finished cheese were analyzed using eight enrichment and detection protocols. Overall, changes in pathogen levels observed throughout manufacture and aging did not differ significantly between MDR and susceptible Salmonella strains. Salmonella counts increased significantly during manufacture to a mean of 734 CFU/g on day 1 followed by a significant decrease over 60 days of aging to <1 CFU/g. Although levels fell and stayed below the direct plating detection limit of $ 5 CFU/g after 54 days on average, viable cells remained detectable after enrichment for an average of 210 ± 40 days. The International Organization for Standardization methods with and without PCR detection provided the most accurate results, and the remaining methods, notably those with selective primary incubation, produced results that disagreed significantly with the true result. Overall, our findings suggest that MDR Salmonella strains may not pose a greater threat to cheese safety than do non-MDR Salmonella strains.

  15. Successful medication withdrawal after cognitive-behavioral therapy in a treatment-resistant preadolescent male with obsessive-compulsive disorder.

    PubMed

    Goldstein, Robert B; Storch, Eric A; Lehmkuhl, Heather; Geffken, Gary R; Goodman, Wayne K; Murphy, Tanya K

    2009-01-01

    There are no reports of a child taking a selective serotonin reuptake inhibitor and an atypical anti-psychotic being successfully tapered from these medications after completion of cognitive-behavioral therapy (CBT) for obsessive-compulsive disorder. With this in mind, we report the case of an 8.5-year-old male who was taking risperidone 0.5 mg bid, sertraline 100 mg, and atomoxetine 25 mg at presentation. After a successful course of CBT, we describe how medications were systematically withdrawn. Implications of this case on practice parameters (e.g., CBT may be an effective augmenting agent for those non-responsive to initial pharmacological treatments) are highlighted. (c) 2008 Wiley-Liss, Inc.

  16. Behavior of tetracycline and sulfamethazine with corresponding resistance genes from swine wastewater in pilot-scale constructed wetlands.

    PubMed

    Liu, Lin; Liu, Yu-Hong; Wang, Zhen; Liu, Chao-Xiang; Huang, Xu; Zhu, Ge-Fu

    2014-08-15

    Four pilot-scale constructed wetlands (free water surface, SF; horizontal subsurface flow, HSF; vertical subsurface flows with different water level, VSF-L and VSF-H) were operated to assess their ability to remove sulfamethazine (SMZ) and tetracycline (TC) from wastewaters, and to investigate the abundance level of corresponding resistance genes (sulI, sulII, tetM, tetW and tetO) in the CWs. The results indicated that CWs could significantly reduce the concentration of antibiotics in wastewater, and the mass removal rate range of SMZ and TC were respectively 11%-95% and 85%-95% in the four systems on the basis of hydraulic equilibrium; further relatively high removal rate was observed in VSF with low water level. Seasonal condition had a significant effect on SMZ removal in the CWs (especially SMZ in SF), but TC removal in VSFs were not considered to have statistically significant differences in winter and summer. At the end period, the relative abundances of target genes in the CWs showed obvious increases compared to initial levels, ranging from 2.98 × 10(-5) to 1.27 × 10(-1) for sul genes and 4.68 × 10(-6) to 1.54 × 10(-1) for tet genes after treatment, and those abundances showed close relation to both characteristic of wastewater and configuration of CWs.

  17. Weld Growth Mechanisms and Failure Behavior of Three-Sheet Resistance Spot Welds Made of 5052 Aluminum Alloy

    NASA Astrophysics Data System (ADS)

    Li, Yang; Yan, Fuyu; Luo, Zhen; Chao, Y. J.; Ao, Sansan; Cui, Xuetuan

    2015-06-01

    This paper investigates the weld nugget formation in three-sheet aluminum alloy resistance spot welding. The nugget formation process in three equal thickness sheets and three unequal thickness sheets of 5052 aluminum alloy were studied. The results showed that the nugget was initially formed at the workpiece/workpiece interfaces (i.e., both upper interface and lower interface). The two small nuggets then grew along the radial direction and axial direction (welding direction) as the welding time increased. Eventually, the two nuggets fused into one large nugget. During the welding process, the Peltier effect between the Cu-Al caused the shift of the nugget in the welding direction. In addition, the mechanical strength and fracture mode of the weld nuggets at the upper and lower interfaces were also studied using tensile shear specimen configuration. Three failure modes were identified, namely interfacial, mixed, and pullout. The critical welding time and critical nugget diameter corresponding to the transitions of these modes were investigated. Finally, an empirical failure load formula for three-sheet weld similar to two-sheet spot weld was developed.

  18. Precipitation behavior and martensite lath coarsening during tempering of T/P92 ferritic heat-resistant steel

    NASA Astrophysics Data System (ADS)

    Xu, Lin-qing; Zhang, Dan-tian; Liu, Yong-chang; Ning, Bao-qun; Qiao, Zhi-xia; Yan, Ze-sheng; Li, Hui-jun

    2014-05-01

    Tempering is an important process for T/P92 ferritic heat-resistant steel from the viewpoint of microstructure control, as it facilitates the formation of final tempered martensite under serving conditions. In this study, we have gained deeper insights on the mechanism underlying the microstructural evolution during tempering treatment, including the precipitation of carbides and the coarsening of martensite laths, as systematically analyzed by optical microscopy, transmission electron microscopy, and high-resolution transmission electron microscopy. The chemical composition of the precipitates was analyzed using energy dispersive X-ray spectroscopy. Results indicate the formation of M3C (cementite) precipitates under normalized conditions. However, they tend to dissolve within a short time of tempering, owing to their low thermal stability. This phenomenon was substantiated by X-ray diffraction analysis. Besides, we could observe the precipitation of fine carbonitrides (MX) along the dislocations. The mechanism of carbon diffusion controlled growth of M23C6 can be expressed by the Zener's equation. The movement of Y-junctions was determined to be the fundamental mechanism underlying the martensite lath coarsening process. Vickers hardness was estimated to determine their mechanical properties. Based on the comprehensive analysis of both the micro-structural evolution and hardness variation, the process of tempering can be separated into three steps.

  19. Effect of Aging on Precipitation Behavior and Pitting Corrosion Resistance of SAF2906 Super Duplex Stainless Steel

    NASA Astrophysics Data System (ADS)

    Li, Jianchun; Li, Guoping; Liang, Wei; Han, Peide; Wang, Hongxia

    2017-09-01

    The effect of aging temperature and holding time on the precipitation of secondary phases and pitting corrosion resistance of SAF2906 super duplex stainless steel was examined. Chromium nitride and σ phase were observed to preferentially precipitate at the ferrite/austenite interface. An amount of nitrides was also observed within the ferrite grain. The precipitation of chromium nitride occurred before the σ phase. The increase in aging temperature and holding time did not affect the concentration of the nitrides but increased the area fraction of the σ phase at a faster rate. The Cr2N precipitation in SAF2906 is more evident than that of the other duplex stainless steels. The variation tendency of the precipitation concentrations is primarily consistent with the prediction results of Thermo-Calc software. The electrochemical results showed that Cr2N and σ phase significantly reduced the pitting potential. Scanning electron microscope observations revealed that pits appear mainly in regions adjacent to sigma phase and Cr2N.

  20. Unusual behavior in the reactivity of 5-substituted-1H-tetrazoles in a resistively heated microreactor

    PubMed Central

    Gutmann, Bernhard; Glasnov, Toma N; Razzaq, Tahseen; Goessler, Walter; Roberge, Dominique M

    2011-01-01

    Summary The decomposition of 5-benzhydryl-1H-tetrazole in an N-methyl-2-pyrrolidone/acetic acid/water mixture was investigated under a variety of high-temperature reaction conditions. Employing a sealed Pyrex glass vial and batch microwave conditions at 240 °C, the tetrazole is comparatively stable and complete decomposition to diphenylmethane requires more than 8 h. Similar kinetic data were obtained in conductively heated flow devices with either stainless steel or Hastelloy coils in the same temperature region. In contrast, in a flow instrument that utilizes direct electric resistance heating of the reactor coil, tetrazole decomposition was dramatically accelerated with rate constants increased by two orders of magnitude. When 5-benzhydryl-1H-tetrazole was exposed to 220 °C in this type of flow reactor, decomposition to diphenylmethane was complete within 10 min. The mechanism and kinetic parameters of tetrazole decomposition under a variety of reaction conditions were investigated. A number of possible explanations for these highly unusual rate accelerations are presented. In addition, general aspects of reactor degradation, corrosion and contamination effects of importance to continuous flow chemistry are discussed. PMID:21647324

  1. Patient and provider perspectives on methicillin-resistant Staphylococcus aureus: a qualitative assessment of knowledge, beliefs, and behavior.

    PubMed

    Hill, Jennifer N; Evans, Charlesnika T; Cameron, Kenzie A; Rogers, Thea J; Risa, Kathleen; Kellie, Susan; Richardson, Michael S A; Anderson, Vicki; Goldstein, Barry; Guihan, Marylou

    2013-03-01

    Methicillin-resistant Staphylococcus aureus (MRSA) is a frequent cause of healthcare-associated infection. Individuals with spinal cord injuries and disorders (SCI/D) are at high risk of MRSA colonization and infection. The Department of Veterans Affairs (VA) released guidelines to prevent the spread of MRSA in Veterans with SCI/D; however, available patient educational materials did not address the unique issues for this population. To assess perceptions of SCI/D providers and Veterans with SCI/D regarding MRSA and their educational needs about MRSA prevention, with an ultimate goal of developing patient educational materials that address the issues unique to SCI/D. Purposive samples of SCI/D providers (six groups) and Veterans with SCI/D (one group) at two VA facilities participated in 60-90-minute focus group sessions. Qualitative data were analyzed using latent content and constant comparative techniques to identify focal themes. Thirty-three providers (physicians and nurses working in inpatient, outpatient, and homecare settings) and eight Veterans participated. Three overarching themes emerged from the analysis: knowledge about MRSA, hand hygiene, and barriers to educating Veterans with SCI/D. SCI/D providers and Veterans with SCI/D identified gaps in general MRSA knowledge, gaps in knowledge of good hand hygiene practices and of required frequency of hand hygiene, and barriers to educating Veterans with SCI/D during inpatient stays. Future educational materials and strategies should address these gaps.

  2. Patient and provider perspectives on methicillin-resistant Staphylococcus aureus: A qualitative assessment of knowledge, beliefs, and behavior

    PubMed Central

    Hill, Jennifer N.; Evans, Charlesnika T.; Cameron, Kenzie A.; Rogers, Thea J.; Risa, Kathleen; Kellie, Susan; Richardson, Michael S.A.; Anderson, Vicki; Goldstein, Barry; Guihan, Marylou

    2013-01-01

    Background Methicillin-resistant Staphylococcus aureus (MRSA) is a frequent cause of healthcare-associated infection. Individuals with spinal cord injuries and disorders (SCI/D) are at high risk of MRSA colonization and infection. The Department of Veterans Affairs (VA) released guidelines to prevent the spread of MRSA in Veterans with SCI/D; however, available patient educational materials did not address the unique issues for this population. Objective To assess perceptions of SCI/D providers and Veterans with SCI/D regarding MRSA and their educational needs about MRSA prevention, with an ultimate goal of developing patient educational materials that address the issues unique to SCI/D. Methods Purposive samples of SCI/D providers (six groups) and Veterans with SCI/D (one group) at two VA facilities participated in 60–90-minute focus group sessions. Qualitative data were analyzed using latent content and constant comparative techniques to identify focal themes. Participants Thirty-three providers (physicians and nurses working in inpatient, outpatient, and homecare settings) and eight Veterans participated. Results Three overarching themes emerged from the analysis: knowledge about MRSA, hand hygiene, and barriers to educating Veterans with SCI/D. Conclusions SCI/D providers and Veterans with SCI/D identified gaps in general MRSA knowledge, gaps in knowledge of good hand hygiene practices and of required frequency of hand hygiene, and barriers to educating Veterans with SCI/D during inpatient stays. Future educational materials and strategies should address these gaps. PMID:23809521

  3. Seeking behavior, place conditioning and resistance to conditioned suppression of feeding in rats intermittently exposed to palatable food

    PubMed Central

    Velázquez-Sánchez, Clara; Santos, Jeffrey W.; Smith, Karen L.; Ferragud, Antonio; Sabino, Valentina; Cottone, Pietro

    2015-01-01

    Binge eating disorder is characterized by excessive consumption of highly palatable food within short periods of time accompanied by loss of control over eating. Extensive evidence provides support for the consideration of binge eating disorder as an addiction-like disorder. In this study, we wanted to determine whether rats undergoing an operant binge-like eating procedure could develop maladaptive forms of conditioned feeding behaviors. For this purpose, we trained male rats to self-administer either a sugary, highly palatable diet (Palatable rats) or a chow diet (Chow rats) for 1 hour a day. Following escalation and stabilization of palatable food intake, we tested Chow and Palatable rats in i) a conditioned place preference test, ii) a second-order schedule of reinforcement, and iii) a cue-induced suppression of feeding test. In the conditioned place preference task, Palatable rats spent significantly more time in the compartment that was previously paired with the palatable food, compared to Chow controls. Furthermore, in the second order schedule of reinforcement task, Palatable rats exhibited active lever responding 4- to 6-fold higher than Chow control rats. Finally, in the cue-induced suppression of feeding test, while Chow control subjects reduced responding by 32% in the presence of the conditioned punishment, Palatable rats persevered in responding despite the aversive cue. These results further characterize this animal model of binge-like eating and provide additional evidence for the addictive properties of highly palatable food. PMID:25798634

  4. Effectiveness of Cognitive Behavioral Therapy in Public Mental Health: Comparison to Treatment as Usual for Treatment -Resistant Depression

    PubMed Central

    Lopez, Molly A.; Basco, Monica A.

    2014-01-01

    State mental health systems have been leaders in the implementation of evidence-based approaches to care for individuals with severe mental illness. Numerous case studies of the wide-scale implementation of research-supported models such as Integrated Dual Diagnosis Treatment and Assertive Community Treatment are documented. However, relatively few dissemination efforts have focused on cognitive behavioral therapy (CBT) for individuals with major depression despite evidence indicating its efficacy with this population. A multi-site effectiveness trial of CBT was conducted within the Texas public mental health system. Eighty-three adults with major depression received CBT from community clinicians trained through a workshop and regular consultation with a master clinician. Outcomes were compared to a matched sample of individuals receiving pharmacotherapy. Outcome measures used included the Quick Inventory of Depressive Symptomatology and Beck Depression Inventory. Individuals receiving CBT showed greater improvements in depression symptoms than those in the comparison group. Greater pre-treatment symptom severity predicted better treatment response, while the presence of comorbid personality disorders was associated with poorer outcomes. PMID:24692026

  5. Seeking behavior, place conditioning, and resistance to conditioned suppression of feeding in rats intermittently exposed to palatable food.

    PubMed

    Velázquez-Sánchez, Clara; Santos, Jeffrey W; Smith, Karen L; Ferragud, Antonio; Sabino, Valentina; Cottone, Pietro

    2015-04-01

    Binge eating disorder is characterized by excessive consumption of highly palatable food within short periods of time accompanied by loss of control over eating. Extensive evidence provides support for the consideration of binge eating disorder as an addiction-like disorder. In this study, we wanted to determine whether rats undergoing an operant binge-like eating procedure could develop maladaptive forms of conditioned feeding behaviors. For this purpose, we trained male rats to self-administer either a sugary, highly palatable diet ("Palatable" rats) or a chow diet ("Chow" rats) for 1 hour a day. After escalation and stabilization of palatable food intake, we tested Chow and Palatable rats in (a) a conditioned place preference test, (b) a second-order schedule of reinforcement, (c) a cue-induced suppression of feeding test. In the conditioned place preference task, Palatable rats spent significantly more time in the compartment that was previously paired with the palatable food, compared to Chow controls. Furthermore, in the second-order schedule of reinforcement task, Palatable rats exhibited active lever responding 4- to 6-fold higher than Chow control rats. Finally, in the cue-induced suppression of feeding test, although Chow control subjects reduced responding by 32% in the presence of the conditioned punishment, Palatable rats persevered in responding despite the aversive cue. These results further characterize this animal model of binge-like eating and provide additional evidence for the addictive properties of highly palatable food.

  6. Effectiveness of cognitive behavioral therapy in public mental health: comparison to treatment as usual for treatment-resistant depression.

    PubMed

    Lopez, Molly A; Basco, Monica A

    2015-01-01

    State mental health systems have been leaders in the implementation of evidence-based approaches to care for individuals with severe mental illness. Numerous case studies of the wide-scale implementation of research-supported models such as integrated dual diagnosis treatment and assertive community treatment are documented. However, relatively few dissemination efforts have focused on cognitive behavioral therapy (CBT) for individuals with major depression despite evidence indicating its efficacy with this population. A multi-site effectiveness trial of CBT was conducted within the Texas public mental health system. Eighty-three adults with major depression received CBT from community clinicians trained through a workshop and regular consultation with a master clinician. Outcomes were compared to a matched sample of individuals receiving pharmacotherapy. Outcome measures used included the quick inventory of depressive symptomatology and beck depression inventory. Individuals receiving CBT showed greater improvements in depression symptoms than those in the comparison group. Greater pre-treatment symptom severity predicted better treatment response, while the presence of comorbid personality disorders was associated with poorer outcomes.

  7. Volatile Organic Compounds Induced by Herbivory of the Soybean Looper Chrysodeixis includens in Transgenic Glyphosate-Resistant Soybean and the Behavioral Effect on the Parasitoid, Meteorus rubens.

    PubMed

    Strapasson, Priscila; Pinto-Zevallos, Delia M; Da Silva Gomes, Sandra M; Zarbin, Paulo H G

    2016-08-01

    Transgenic soybean plants (RR) engineered to express resistance to glyphosate harbor a variant of the enzyme EPSPS (5-enolpyruvylshikimate-3-phosphate synthase) involved in the shikimic acid pathway, the biosynthetic route of three aromatic amino acids: phenylalanine, tyrosine, and tryptophan. The insertion of the variant enzyme CP4 EPSPS confers resistance to glyphosate. During the process of genetic engineering, unintended secondary effects are likely to occur. In the present study, we quantified volatile organic compounds (VOCs) emitted constitutively or induced in response to herbivory by the soybean looper Chrysodeixis includens in transgenic soybean and its isogenic (untransformed) line. Since herbivore-induced plant volatiles (HIPVs) are known to play a role in the recruitment of natural enemies, we assessed whether changes in VOC profiles alter the foraging behavior of the generalist endoparasitic larval parasitoid, Meteorus rubens in the transgenic line. Additionally, we assessed whether there was a difference in plant quality by measuring the weight gain of the soybean looper. In response to herbivory, several VOCs were induced in both the conventional and the transgenic line; however, larger quantities of a few compounds were emitted by transgenic plants. Meteorus rubens females were able to discriminate between the odors of undamaged and C. includens-damaged plants in both lines, but preferred the odors emitted by herbivore-damaged transgenic plants over those emitted by herbivore-damaged conventional soybean plants. No differences were observed in the weight gain of the soybean looper. Our results suggest that VOC-mediated tritrophic interactions in this model system are not negatively affected. However, as the preference of the wasps shifted towards damaged transgenic plants, the results also suggest that genetic modification affects that tritrophic interactions in multiple ways in this model system.

  8. Antiferromagnetic spin correlations and pseudogaplike behavior in Ca(Fe1-xCox)2As2 studied by 75As nuclear magnetic resonance and anisotropic resistivity

    DOE PAGES

    Cui, J.; Roy, B.; Tanatar, M. A.; ...

    2015-11-06

    We report 75As nuclear magnetic resonance (NMR) measurements of single-crystalline Ca(Fe1–xCox)2As2 (x=0.023, 0.028, 0.033, and 0.059) annealed at 350°C for 7 days. From the observation of a characteristic shape of 75As NMR spectra in the stripe-type antiferromagnetic (AFM) state, as in the case of x=0 (TN=170 K), clear evidence for the commensurate AFM phase transition with the concomitant structural phase transition is observed in x=0.023 (TN=106 K) and x=0.028 (TN=53 K). Through the temperature dependence of the Knight shifts and the nuclear spin lattice relaxation rates (1/T1), although stripe-type AFM spin fluctuations are realized in the paramagnetic state as inmore » the case of other iron pnictide superconductors, we found a gradual decrease of the AFM spin fluctuations below a crossover temperature T* that was nearly independent of Co-substitution concentration, and it is attributed to a pseudogaplike behavior in the spin excitation spectra of these systems. The T* feature finds correlation with features in the temperature-dependent interplane resistivity, ρc(T), but not with the in-plane resistivity ρa(T). The temperature evolution of anisotropic stripe-type AFM spin fluctuations is tracked in the paramagnetic and pseudogap phases by the 1/T1 data measured under magnetic fields parallel and perpendicular to the c axis. As a result, based on our NMR data, we have added a pseudogaplike phase to the magnetic and electronic phase diagram of Ca(Fe1–xCox)2As2.« less

  9. Effects of two-step homogenization on precipitation behavior of Al{sub 3}Zr dispersoids and recrystallization resistance in 7150 aluminum alloy

    SciTech Connect

    Guo, Zhanying; Zhao, Gang; Chen, X.-Grant

    2015-04-15

    The effect of two-step homogenization treatments on the precipitation behavior of Al{sub 3}Zr dispersoids was investigated by transmission electron microscopy (TEM) in 7150 alloys. Two-step treatments with the first step in the temperature range of 300–400 °C followed by the second step at 470 °C were applied during homogenization. Compared with the conventional one-step homogenization, both a finer particle size and a higher number density of Al{sub 3}Zr dispersoids were obtained with two-step homogenization treatments. The most effective dispersoid distribution was attained using the first step held at 300 °C. In addition, the two-step homogenization minimized the precipitate free zones and greatly increased the number density of dispersoids near dendrite grain boundaries. The effect of two-step homogenization on recrystallization resistance of 7150 alloys with different Zr contents was quantitatively analyzed using the electron backscattered diffraction (EBSD) technique. It was found that the improved dispersoid distribution through the two-step treatment can effectively inhibit the recrystallization process during the post-deformation annealing for 7150 alloys containing 0.04–0.09 wt.% Zr, resulting in a remarkable reduction of the volume fraction and grain size of recrystallization grains. - Highlights: • Effect of two-step homogenization on Al{sub 3}Zr dispersoids was investigated by TEM. • Finer and higher number of dispersoids obtained with two-step homogenization • Minimized the precipitate free zones and improved the dispersoid distribution • Recrystallization resistance with varying Zr content was quantified by EBSD. • Effectively inhibit the recrystallization through two-step treatments in 7150 alloy.

  10. Alterations in Ethanol-Induced Behaviors and Consumption in Knock-In Mice Expressing Ethanol-Resistant NMDA Receptors

    PubMed Central

    den Hartog, Carolina R.; Beckley, Jacob T.; Smothers, Thetford C.; Lench, Daniel H.; Holseberg, Zack L.; Fedarovich, Hleb; Gilstrap, Meghin J.; Homanics, Gregg E.; Woodward, John J.

    2013-01-01

    Ethanol's action on the brain likely reflects altered function of key ion channels such as glutamatergic N-methyl-D-aspartate receptors (NMDARs). In this study, we determined how expression of a mutant GluN1 subunit (F639A) that reduces ethanol inhibition of NMDARs affects ethanol-induced behaviors in mice. Mice homozygous for the F639A allele died prematurely while heterozygous knock-in mice grew and bred normally. Ethanol (44 mM; ∼0.2 g/dl) significantly inhibited NMDA-mediated EPSCs in wild-type mice but had little effect on responses in knock-in mice. Knock-in mice had normal expression of GluN1 and GluN2B protein across different brain regions and a small reduction in levels of GluN2A in medial prefrontal cortex. Ethanol (0.75–2.0 g/kg; IP) increased locomotor activity in wild-type mice but had no effect on knock-in mice while MK-801 enhanced activity to the same extent in both groups. Ethanol (2.0 g/kg) reduced rotarod performance equally in both groups but knock-in mice recovered faster following a higher dose (2.5 g/kg). In the elevated zero maze, knock-in mice had a blunted anxiolytic response to ethanol (1.25 g/kg) as compared to wild-type animals. No differences were noted between wild-type and knock-in mice for ethanol-induced loss of righting reflex, sleep time, hypothermia or ethanol metabolism. Knock-in mice consumed less ethanol than wild-type mice during daily limited-access sessions but drank more in an intermittent 24 h access paradigm with no change in taste reactivity or conditioned taste aversion. Overall, these data support the hypothesis that NMDA receptors are important in regulating a specific constellation of effects following exposure to ethanol. PMID:24244696

  11. Reduced risk for metabolic syndrome and insulin resistance associated with ovo-lacto-vegetarian behavior in female Buddhists: a case-control study.

    PubMed

    Chiang, Jui-Kun; Lin, Ying-Lung; Chen, Chi-Ling; Ouyang, Chung-Mei; Wu, Ying-Tai; Chi, Yu-Chiao; Huang, Kuo-Chin; Yang, Wei-Shiung

    2013-01-01

    The association of vegetarian status with the risk of metabolic syndrome (MetS) is not clear. In Asia, Buddhists often have vegetarian behavior for religious rather than for health reasons. We hypothesize that the vegetarian in Buddhism is associated with better metabolic profiles, lower risk for the MetS and insulin resistance (IR). We enrolled 391 female vegetarians (~80% lacto-ovo-vegetarians) and 315 non-vegetarians from health-checkup clinics at a Buddhist hospital in Taiwan. The vegetarian status was associated with lower body mass index, smaller waist circumference, lower total cholesterol, lower low density lipoprotein-cholesterol (LDL-C), and lower HDL-C in multivariate linear regression analyses. Despite having lower HDL-C level, the vegetarians had significantly lower total cholesterol/HDL-C and LDL-C/HDL-C ratios. After adjusting the other covariates, the risks for the MetS were lower for ovo-lacto-vegetarians of 1-11 years and >11 years respectively by 54% (odds ratio [OR] =0.46, 95%C.I.:0.26-0.79) and 57% (OR=0.43, 95%C.I.:0.23-0.76) compared to non-vegetarians by the IDF criteria. Likewise, they were lower respectively by 45% (OR=0.55, 95%C.I.:0.32-0.92) and 42% (OR=0.58, 95%C.I.:0.33-0.997), for the MetS by the modified NCEP criteria. In the subgroup of non-diabetic subjects, the vegetarians also had lower risk for IR by HOMA compared to the non-vegetarians (OR=0.71, 95%C.I.:0.48-1.06). The vegetarian behavior, mainly lacto-ovo-vegetarian, related to Buddhism, although not meant for its health effects, is associated with reduced risk for the MetS and IR and may potentially provide metabolic and cardiovascular protective effects in women.

  12. Resistance to the development of stress-induced behavioral despair in the forced swim test associated with elevated hippocampal Bcl-xl expression.

    PubMed

    Shishkina, Galina T; Kalinina, Tatyana S; Berezova, Inna V; Bulygina, Veta V; Dygalo, Nikolay N

    2010-12-01

    Stress may predispose individuals toward depression through down-regulation of neurogenesis and increase in apoptosis in the brain. However, many subjects show high resistance to stress in relation to psychopathology. In the present study, we assessed the possibility that individual-specific patterns of gene expression associated with cell survival and proliferation may be among the molecular factors underlying stress resilience. Brain-derived neurotrophic factor (BDNF), anti-apoptotic B cell lymphoma like X (Bcl-xl) and pro-apoptotic bcl2-associated X protein (Bax) expression were determined in the hippocampus and frontal cortex of rats naturally differed in despair-like behavior in the forced swim test. In the hippocampus, BDNF messenger RNA (mRNA) level was significantly down-regulated 2h after the forced swim test exposure, and at this time point, Bcl-xl mRNA and protein levels were significantly higher in stressed than in untested animals. The ratios of hippocampal Bcl-xl to Bax mRNA negatively correlated with the total time spent immobile in the test. When animals were divided in two groups according to immobility responses in two consecutive swim sessions and designated as stress resilient if their immobility time did not increase in the second session as it did in stress sensitive rats, it was found that resilient rats had significantly higher Bcl-xl/Bax ratios in the hippocampus than stress sensitive animals. The data suggest that naturally occurring variations in the Bcl-xl/Bax ratio in the hippocampus may contribute to individual differences in vulnerability to stress-induced depression-like behaviors.

  13. Resident resistance.

    PubMed

    Price, J L; Cleary, B

    1999-01-01

    Clearly, faculty must work hard with residents to explore the nature of their resistance to a program's learning and growth opportunities. Initial steps to a deeper, more effective, and longer-lasting change process must be pursued. If resident resistance is mishandled or misunderstood, then learning and professional growth may be sidetracked and the purposes of residency training defeated. Listening to the whole person of the resident and avoiding the trap of getting caught up in merely responding to select resident behaviors that irritate us is critical. Every faculty member in the family practice residency program must recognize resistance as a form of defense that cannot immediately be torn down or taken away. Resident defenses have important purposes to play in stress reduction even if they are not always healthy. Residents, especially interns, use resistance to avoid a deeper and more truthful look at themselves as physicians. A family practice residency program that sees whole persons in their residents and that respects resident defenses will effectively manage the stress and disharmony inherent to the resistant resident.

  14. Spin-Filtering Rectifying and Negative Differential Resistance Behaviors in Co(dmit)2 Molecular Devices with Monatomic (C, Fe, Au) Electrodes

    NASA Astrophysics Data System (ADS)

    Yan, Shenlang; Long, Mengqiu; Zhang, Xiaojiao; He, Jun; Xu, Hui; Gao, Yongli

    2014-09-01

    Using nonequilibrium Green's functions (NEGFs) combined with the density functional theory (DFT), we study the electronic transport properties of a single molecule magnet Co(dmit)2, which is sandwiched between two monatomic chain electrodes, and the different electrode materials carbon, iron and gold, have been considered. The results show that the electrodes play a crucial role in the spin-dependent transport of the Co(dmit)2 molecular device, and some interesting phenomenon, such as perfect spin-filtering effect, rectifying and negative differential resistance (NDR) can be observed. We demonstrated that the magnetic Fe electrode can lead to high spin-flittering effect, and the different hybridization and alignment of energy levels between the molecule and the electrodes may be responsible for the rectification performance, and the distributions (delocalization or localization) of the frontier molecular orbitals under different bias result in the NDR behaviors. These characteristics could be used in the study of spin physics and the realization of nanospintronic devices.

  15. Resistant to the Recession: Low-Income Adults’ Maintenance of Cooking and Away-From-Home Eating Behaviors During Times of Economic Turbulence

    PubMed Central

    Smith, Lindsey P.; Ng, Shu Wen

    2014-01-01

    Objectives. We examined the effects of state-level unemployment rates during the recession of 2008 on patterns of home food preparation and away-from-home (AFH) eating among low-income and minority populations. Methods. We analyzed pooled cross-sectional data on 118 635 adults aged 18 years or older who took part in the American Time Use Study. Multinomial logistic regression models stratified by gender were used to evaluate the associations between state-level unemployment, poverty, race/ethnicity, and time spent cooking, and log binomial regression was used to assess respondents’ AFH consumption patterns. Results. High state-level unemployment was associated with only trivial increases in respondents’ cooking patterns and virtually no change in their AFH eating patterns. Low-income and racial/ethnic minority groups were not disproportionately affected by the recession. Conclusions. Even during a major economic downturn, US adults are resistant to food-related behavior change. More work is needed to understand whether this reluctance to change is attributable to time limits, lack of knowledge or skill related to food preparation, or lack of access to fresh produce and raw ingredients. PMID:24625145

  16. Antimicrobial (Drug) Resistance

    MedlinePlus

    ... NIAID invests in basic research to understand the biology of microbes, their behavior, and how drug resistance ... Nucleotide Polymorphism Phylogenetics & Ontology Proteomics & Protein Analysis Systems Biology Data Portals Software Applications BCBB Mobyle Interface Designer ( ...

  17. Phase behavior of block copolymers in compressed carbon dioxide and as single domain-layer, nanolithographic etch resists for sub-10 nm pattern transfer

    NASA Astrophysics Data System (ADS)

    Chandler, Curran Matthew

    Diblock copolymers have many interesting properties, which first and foremost include their ability to self-assemble into various ordered, regularly spaced domains with nanometer-scale feature sizes. The work in this dissertation can be logically divided into two parts -- the first and the majority of this work describes the phase behavior of certain block copolymer systems, and the second discusses real applications possible with block copolymer templates. Many compressible fluids have solvent-like properties dependent on fluid pressure and can be used as processing aids similar to liquid solvents. Here, compressed CO2 was shown to swell several thin homopolymer films, including polystyrene and polyisoprene, as measured by high pressure ellipsometry at elevated temperatures and pressures. The ellipsometric technique was modified to produce accurate data at these conditions through a custom pressure vessel design. The order-disorder transition (ODT) temperatures of several poly(styrene-bisoprene) diblock copolymers were also investigated by static birefringence when dilated with compressed CO2. Sorption of CO2 in each copolymer resulted in significant depressions of the ODT temperature as a function of fluid pressure, and the data above was used to estimate the quantitative amount of solvent in each of the diblock copolymers. These depressions were not shown to follow dilution approximation, and showed interesting, exaggerated scaling of the ODT at near-bulk polymer concentrations. The phase behavior of block copolymer surfactants was studied when blended with polymer or small molecule additives capable of selective hydrogen bonds. This work used small angle X-ray scattering (SAXS) to identify several low molecular weight systems with strong phase separation and ordered domains as small as 2--3 nanometers upon blending. One blend of a commercially-available surfactant with a small molecule additive was further developed and showed promise as a thin-film pattern

  18. Reduced Risk for Metabolic Syndrome and Insulin Resistance Associated with Ovo-Lacto-Vegetarian Behavior in Female Buddhists: A Case-Control Study

    PubMed Central

    Chiang, Jui-Kun; Lin, Ying-Lung; Chen, Chi-Ling; Ouyang, Chung-Mei; Wu, Ying-Tai; Chi, Yu-Chiao; Huang, Kuo-Chin; Yang, Wei-Shiung

    2013-01-01

    Introduction The association of vegetarian status with the risk of metabolic syndrome (MetS) is not clear. In Asia, Buddhists often have vegetarian behavior for religious rather than for health reasons. We hypothesize that the vegetarian in Buddhism is associated with better metabolic profiles, lower risk for the MetS and insulin resistance (IR). Methods We enrolled 391 female vegetarians (∼80% lacto-ovo-vegetarians) and 315 non-vegetarians from health-checkup clinics at a Buddhist hospital in Taiwan. Results The vegetarian status was associated with lower body mass index, smaller waist circumference, lower total cholesterol, lower low density lipoprotein-cholesterol (LDL-C), and lower HDL-C in multivariate linear regression analyses. Despite having lower HDL-C level, the vegetarians had significantly lower total cholesterol/HDL-C and LDL-C/HDL-C ratios. After adjusting the other covariates, the risks for the MetS were lower for ovo-lacto-vegetarians of 1–11 years and >11 years respectively by 54% (odds ratio [OR] = 0.46, 95%C.I.:0.26–0.79) and 57% (OR = 0.43, 95%C.I.:0.23–0.76) compared to non-vegetarians by the IDF criteria. Likewise, they were lower respectively by 45% (OR = 0.55, 95%C.I.:0.32–0.92) and 42% (OR = 0.58, 95%C.I.:0.33–0.997), for the MetS by the modified NCEP criteria. In the subgroup of non-diabetic subjects, the vegetarians also had lower risk for IR by HOMA compared to the non-vegetarians (OR = 0.71, 95%C.I.:0.48–1.06). Conclusion The vegetarian behavior, mainly lacto-ovo-vegetarian, related to Buddhism, although not meant for its health effects, is associated with reduced risk for the MetS and IR and may potentially provide metabolic and cardiovascular protective effects in women. PMID:23951247

  19. Resistance-resistant antibiotics.

    PubMed

    Oldfield, Eric; Feng, Xinxin

    2014-12-01

    New antibiotics are needed because drug resistance is increasing while the introduction of new antibiotics is decreasing. We discuss here six possible approaches to develop 'resistance-resistant' antibiotics. First, multitarget inhibitors in which a single compound inhibits more than one target may be easier to develop than conventional combination therapies with two new drugs. Second, inhibiting multiple targets in the same metabolic pathway is expected to be an effective strategy owing to synergy. Third, discovering multiple-target inhibitors should be possible by using sequential virtual screening. Fourth, repurposing existing drugs can lead to combinations of multitarget therapeutics. Fifth, targets need not be proteins. Sixth, inhibiting virulence factor formation and boosting innate immunity may also lead to decreased susceptibility to resistance. Although it is not possible to eliminate resistance, the approaches reviewed here offer several possibilities for reducing the effects of mutations and, in some cases, suggest that sensitivity to existing antibiotics may be restored in otherwise drug-resistant organisms.

  20. Diet-induced obesity resistance of adult female mice selectively bred for increased wheel-running behavior is reversed by single perinatal exposure to a high-energy diet.

    PubMed

    Guidotti, Stefano; Meyer, Neele; Przybyt, Ewa; Scheurink, Anton J W; Harmsen, Martin C; Garland, Theodore; van Dijk, Gertjan

    2016-04-01

    Female mice from independently bred lines previously selected over 50 generations for increased voluntary wheel-running behavior (S1, S2) resist high energy (HE) diet-induced obesity (DIO) at adulthood, even without actual access to running wheels, as opposed to randomly bred controls (CON). We investigated whether adult S mice without wheels remain DIO-resistant when exposed - via the mother - to the HE diet during their perinatal stage (from 2 weeks prior to conception until weaning on post-natal day 21). While S1 and S2 females subjected to HE diet either perinatally or from weaning onwards (post-weaning) resisted increased adiposity at adulthood (as opposed to CON females), they lost this resistance when challenged with HE diet during these periods combined over one single cycle of breeding. When allowed one-week access to wheels (at week 6-8 and at 10 months), however, tendency for increased wheel-running behavior of S mice was unaltered. Thus, the trait for increased wheel-running behavior remained intact following combined perinatal and post-weaning HE exposure, but apparently this did not block HE-induced weight gain. At weaning, perinatal HE diet increased adiposity in all lines, but this was only associated with hyperleptinemia in S lines irrespective of gender. Because leptin has multiple developmental effects at adolescence, we argue that a trait for increased physical activity may advance maturation in times of plenty. This would be adaptive in nature where episodes of increased nutrient availability should be exploited maximally. Associated disturbances in glucose homeostasis and related co-morbidities at adulthood are probably pleiotropic side effects. Copyright © 2016 Elsevier Inc. All rights reserved.

  1. Influence of carbon content on the copper-telluride phase formation and on the resistive switching behavior of carbon alloyed Cu-Te conductive bridge random access memory cells

    SciTech Connect

    Devulder, Wouter De Schutter, Bob; Detavernier, Christophe; Opsomer, Karl; Franquet, Alexis; Meersschaut, Johan; Muller, Robert; Van Elshocht, Sven; Jurczak, Malgorzata; Goux, Ludovic; Belmonte, Attilio

    2014-02-07

    In this paper, we investigate the influence of the carbon content on the Cu-Te phase formation and on the resistive switching behavior in carbon alloyed Cu{sub 0.6}Te{sub 0.4} based conductive bridge random access memory (CBRAM) cells. Carbon alloying of copper-tellurium inhibits the crystallization, while attractive switching behavior is preserved when using the material as Cu-supply layer in CBRAM cells. The phase formation is first investigated in a combinatorial way. With increasing carbon content, an enlargement of the temperature window in which the material stays amorphous was observed. Moreover, if crystalline phases are formed, subsequent phase transformations are inhibited. The electrical switching behavior of memory cells with different carbon contents is then investigated by implementing them in 580 μm diameter dot TiN/Cu{sub 0.6}Te{sub 0.4}-C/Al{sub 2}O{sub 3}/Si memory cells. Reliable switching behavior is observed for carbon contents up to 40 at. %, with a resistive window of more than 2 orders of magnitude, whereas for 50 at. % carbon, a higher current in the off state and only a small resistive window are present after repeated cycling. This degradation can be ascribed to the higher thermal and lower drift contribution to the reset operation due to a lower Cu affinity towards the supply layer, leading cycle-after-cycle to an increasing amount of Cu in the switching layer, which contributes to the current. The thermal diffusion of Cu into Al{sub 2}O{sub 3} under annealing also gives an indication of the Cu affinity of the source layer. Time of flight secondary ion mass spectroscopy was used to investigate this migration depth in Al{sub 2}O{sub 3} before and after annealing, showing a higher Cu, Te, and C migration for high carbon contents.

  2. Interventions for Dealing with Resistance.

    ERIC Educational Resources Information Center

    Lambert, Dorinda J.

    Basic intervention strategies for dealing with client resistance include psychoanalytic, learning/behavioral, and hypnotic/paradoxical. Psychoanalytic theory views resistance as a way to avoid the anxiety aroused by increasing awareness of unconscious materials and vulnerable areas in the person's life. Resistance is dealt with after it has…

  3. The effect of a Ta oxygen scavenger layer on HfO2-based resistive switching behavior: thermodynamic stability, electronic structure, and low-bias transport.

    PubMed

    Zhong, Xiaoliang; Rungger, Ivan; Zapol, Peter; Nakamura, Hisao; Asai, Yoshihiro; Heinonen, Olle

    2016-03-14

    Reversible resistive switching between high-resistance and low-resistance states in metal-oxide-metal heterostructures makes them very interesting for applications in random access memories. While recent experimental work has shown that inserting a metallic "oxygen scavenger layer" between the positive electrode and oxide improves device performance, the fundamental understanding of how the scavenger layer modifies the heterostructure properties is lacking. We use density functional theory to calculate thermodynamic properties and conductance of TiN/HfO2/TiN heterostructures with and without a Ta scavenger layer. First, we show that Ta insertion lowers the formation energy of low-resistance states. Second, while the Ta scavenger layer reduces the Schottky barrier height in the high-resistance state by modifying the interface charge at the oxide-electrode interface, the heterostructure maintains a high resistance ratio between high- and low-resistance states. Finally, we show that the low-bias conductance of device on-states becomes much less sensitive to the spatial distribution of oxygen removed from the HfO2 in the presence of the Ta layer. By providing a fundamental understanding of the observed improvements with scavenger layers, we open a path to engineer interfaces with oxygen scavenger layers to control and enhance device performance. In turn, this may enable the realization of a non-volatile low-power memory technology with concomitant reduction in energy consumption by consumer electronics and offering significant benefits to society.

  4. Enhanced resistive switching and multilevel behavior in bilayered HfAlO/HfAlO{sub x} structures for non-volatile memory applications

    SciTech Connect

    Faita, F. L.; Silva, J. P. B.; Pereira, M.; Gomes, M. J. M.

    2015-12-14

    In this work, hafnium aluminum oxide (HfAlO) thin films were deposited by ion beam sputtering deposition technique on Si substrate. The presence of oxygen vacancies in the HfAlO{sub x} layer deposited in oxygen deficient environment is evidenced from the photoluminescence spectra. Furthermore, HfAlO(oxygen rich)/HfAlO{sub x}(oxygen poor) bilayer structures exhibit multilevel resistive switching (RS), and the switching ratio becomes more prominent with increasing the HfAlO layer thickness. The bilayer structure with HfAlO/HfAlO{sub x} thickness of 30/40 nm displays the enhanced multilevel resistive switching characteristics, where the high resistance state/intermediate resistance state (IRS) and IRS/low resistance state resistance ratios are ≈10{sup 2} and ≈5 × 10{sup 5}, respectively. The switching mechanisms in the bilayer structures were investigated by the temperature dependence of the three resistance states. This study revealed that the multilevel RS is attributed to the coupling of ionic conduction and the metallic conduction, being the first associated to the formation and rupture of conductive filaments related to oxygen vacancies and the second with the formation of a metallic filament. Moreover, the bilayer structures exhibit good endurance and stability in time.

  5. Mechanism for bipolar resistive switching memory behaviors of a self-assembled three-dimensional MoS2 microsphere composed active layer

    NASA Astrophysics Data System (ADS)

    Zhou, G. D.; Lu, Z. S.; Yao, Y. Q.; Wang, G.; Yang, X. D.; Zhou, A. K.; Li, P.; Ding, B. F.; Song, Q. L.

    2017-04-01

    A self-assembled three-dimensional (3-D) MoS2 microsphere-based memristor with a favorable ON/OFF resistance ratio of ˜104, endurance, and retention time is demonstrated at room temperature. The formation and rupture of a localized Ag metallic filament, establishment and destruction of a boundary-based hopping path, and charge trapping and detrapping from the space charge region co-contribute to the bipolar resistive switching memory behaviours observed in the device of Ag/MoS2/ITO. This work may give insight into the mechanism of the resistive switching memory behaviours of a device with a 3-D micro-scale.

  6. Antimicrobial Resistance

    MedlinePlus

    ... spread of antimicrobial resistance. Present situation Resistance in bacteria Antibiotic resistance is present in every country. Patients with infections caused by drug-resistant bacteria are at increased risk of worse clinical outcomes ...

  7. Effects of a resistively coated dielectric strip on the TM-polarized resonant backscatter behavior of a slotted conducting rectangular shell

    NASA Astrophysics Data System (ADS)

    Wu, Lin-Kun; Lu, Cheng-Hung

    1993-06-01

    The performance of a resistively coated dielectric strip used to suppress the first TM-type resonant backscatter associated with a 2D slotted conducting rectangular shell is analyzed in this paper using the moment method technique. Results obtained indicate that almost perfect resonance damping performances are attained when a finite-dimensioned resistively coated dielectric strip with dielectric constant epsilon(r) = 4 - j(0.4) and film resistance R(s) = 188.5 ohms is placed: (1) at the slot (which directly faces the normally incident TM-polarized plane wave), (2) on the interior perimeter of the shell adjacent to the slot, or (3) at the center of the back wall of the shell. Poorer damping performances are observed, however, when the resistively coated dielectric strip is placed at other positions and/or with the same or higher film resistance. Finally, it is also shown that in general the knowledge of the waveguide theory can be used advantageously in the placement of the resistively coated dielectric strip for achieving best resonance damping performance.

  8. Two regimes behavior in the resistivity of the La 1.85Sr 0.15Cu 1- xLi xO 4 system: A signature of different electronic states for holes

    NASA Astrophysics Data System (ADS)

    García, S.; Musa, J. E.; Giordanengo, B.; Baggio-Saitovitch, E. M.

    1998-01-01

    The variations of the normal-state resistivity and the superconducting transition temperature Tc of the La 1.85Sr 0.15(Cu 1- xLi x)O 4 system for 0 ≤ x ≤ 0.05 reveal a two regimes behavior, with x ≅ 0.03 being the critical concentration for a transition from a delocalized state, with a reduction of the resistivity values while Tc remains unchanged, to an early stage of a spin compensation process, characterized by Tc suppression without broadening. Disorder at the CuO 2 planes is proposed to be the source of localization and Tc depletion, as supported by fitting of the normal-state curves according to different conduction models.

  9. The effect of a Ta oxygen scavenger layer on HfO2-based resistive switching behavior: Thermodynamic stability, electronic structure, and low-bias transport

    DOE PAGES

    Zhong, Xiaoliang; Rungger, Ivan; Zapol, Peter; ...

    2016-02-15

    Reversible resistive switching between high-resistance and low-resistance states in metal-oxide-metal heterostructures makes them very interesting for applications in random access memories. While recent experimental work has shown that inserting a metallic "oxygen scavenger layer'' between the positive electrode and oxide improves device performance, the fundamental understanding of how the scavenger layer modifies the heterostructure properties is lacking. We use density functional theory to calculate thermodynamic properties and conductance of TiN/HfO2/TiN heterostructures with and without a Ta scavenger layer. First, we show that Ta insertion lowers the formation energy of low-resistance states. Second, while the Ta scavenger layer reduces the Schottkymore » barrier height in the high-resistance state by modifying the interface charge at the oxide-electrode interface, the heterostructure maintains a high resistance ratio between high-and low-resistance states. Lastly, we show that the low-bias conductance of device on-states becomes much less sensitive to the spatial distribution of oxygen removed from the HfO2 in the presence of the Ta layer. By providing a fundamental understanding of the observed improvements with scavenger layers, we open a path to engineer interfaces with oxygen scavenger layers to control and enhance device performance. In turn, this may enable the realization of a non-volatile low-power memory technology with concomitant reduction in energy consumption by consumer electronics and offering significant benefits to society.« less

  10. Structure and optical properties of polycrystalline NiO films and its resistive switching behavior in Au/NiO/Pt structures

    NASA Astrophysics Data System (ADS)

    Lai, J. C.; Wang, X. C.; Mi, W. B.; Ding, Y. H.; Yang, B. H.

    2015-12-01

    Structure and optical of polycrystalline NiO films fabricated by reactive sputtering and its resistive switching properties in Au/NiO/Pt structures are investigated. The size of surface uniform pyramid-like islands and average surface roughness increase with the increase of NiO film thickness (t). The NiO films grow with the preferred (111) orientation at 400 °C, but both (100) and (110)-oriented grains exist in the films fabricated at room temperature. Raman results reveal that the crystallinity of the films fabricated at 400 °C becomes good by comparing with that at room temperature. The optical band gap monotonically decreases from 4.44 eV at t=22 nm to 3.55 eV at t=800 nm. The resistance of the Au/NiO/Pt/Ti/glass structures could be switched between two stable states including low and high resistance states. The bipolar endurance performance of the resistive switching remains nondegradable after 200 cycles. The resistive switching can be ascribed to the carrier trapping and detrapping induced by the electric field, which can change the thickness of the depletion layer at Au/NiO interface.

  11. AIMS and resist simulation

    NASA Astrophysics Data System (ADS)

    Strößner, Ulrich; Seitz, Holger; Birkner, Robert; Richter, Rigo; Scherübl, Thomas

    2008-10-01

    The AIMTM45-193i is the established tool for mask performance qualification and defect printing analysis in the mask shop under scanner conditions. Vector effects are taken into account by the proprietary Zeiss vector effect emulator. In several studies an excellent correlation to wafer prints has been reported. However, a systematic offset to wafer prints in terms of mask error enhancement factor (MEEF) and exposure latitude has been observed which is attributed to well known resist effects. The AIMSTM measures the aerial image in resist whereas in a real lithography process further image blur of the latent image is caused by photo acid diffusion during wafer processing and resist development. To explain the gap between the AIMTM and wafer prints we have investigated aerial images in combination with an easy to use resist model. It does take resist effects into account with sufficient accuracy to explain printing behavior of photo masks but without the need to calibrate lots of parameters of the actually used resist which usually are not known to a mask shop. The resist effects predominantly reduce the image contrast and thus increase the MEEF and the sensitivity to mask defects. This somewhat counterintuitive behavior is labeled "contrast enhancement by contrast reduction". Additionally application of the resist model improves the agreement of e.g. the exposure latitude or MEEF measured by the AIMSTM compared to wafer prints.

  12. Resistance-Resistant Antibiotics

    PubMed Central

    Oldfield, Eric; Feng, Xinxin

    2014-01-01

    New antibiotics are needed because as drug resistance is increasing, the introduction of new antibiotics is decreasing. Here, we discuss six possible approaches to develop ‘resistance-resistant’ antibiotics. First, multi-target inhibitors in which a single compound inhibits more than one target may be easier to develop than conventional combination therapies with two new drugs. Second, inhibiting multiple targets in the same metabolic pathway is expected to be an effective strategy due to synergy. Third, discovering multiple-target inhibitors should be possible by using sequential virtual screening. Fourth, re-purposing existing drugs can lead to combinations of multi-target therapeutics. Fifth, targets need not be proteins. Sixth, inhibiting virulence factor formation and boosting innate immunity may also lead to decreased susceptibility to resistance. Although it is not possible to eliminate resistance, the approaches reviewed here offer several possibilities for reducing the effects of mutations and in some cases suggest that sensitivity to existing antibiotics may be restored, in otherwise drug resistant organisms. PMID:25458541

  13. Resistive switching and magnetic behavior of Bi0.8Ba0.2FeO3 / SrRuO3 / SrTiO3 films: role of thickness-dependent strain

    NASA Astrophysics Data System (ADS)

    Vagadia, Megha; Ravalia, Ashish; Trivedi, Priyanka; Jethva, Sadaf; Katba, Savan; Kuberkar, D. G.

    2016-05-01

    The thickness-dependent resistive switching and magnetic behavior of Bi0.8Ba0.2FeO3/SRO/STO (1 0 0) films have been studied in the context of strain modifications introduced by varying the film thickness. Generation of misfit dislocation results in strain relaxation with an increase in film thickness. All films (50, 100 and 200 nm) show hysteresis in I-V behavior at room temperature with applied voltage V max  =  ±5 V. Fitting of I-V data suggests that trap-controlled SCLC governs the conduction in HRS in the 50 nm film while in the 100 nm and 200 nm films, the charge transport mechanism is ohmic-type throughout the applied field. The ON/OFF switching ratio and current retention performance decrease with an increase in film thickness, suggesting that substrate-induced strain and interface modifications play an important role in governing the resistive switching mechanism in Bi0.8Ba0.2FeO3 films. A film with lower thickness ~50 nm is found to exhibit the highest magnetization which may be attributed to the increase in oxygen vacancies and compressive strain.

  14. Drug Resistance

    MedlinePlus

    HIV Treatment Drug Resistance (Last updated 3/2/2017; last reviewed 3/2/2017) Key Points As HIV multiplies in the ... the risk of drug resistance. What is HIV drug resistance? Once a person becomes infected with HIV, ...

  15. Resistive switching and threshold switching behaviors in La0.1Bi0.9Fe1-xCoxO3 ceramics

    NASA Astrophysics Data System (ADS)

    Wang, S. Y.; Liu, W. F.; Gao, J.; Qiu, Xue; Feng, Yu; Hou, X. G.; Yu, D. S.; Li, D. J.

    2012-08-01

    The effects of cobalt doping on the electrical conductivity of La0.1Bi0.9Fe1-xCoxO3 (LBFCO, x = 0, 0.01, 0.03) ceramics were investigated. It is found that the leakage current increases with cobalt dopant concentration in LBFCO. On the application of bias voltage LBFCO ceramics with cobalt doping exhibits resistive switching effects at room temperature and threshold switching effects at elevated temperatures (50 °C and 80 °C). X-ray photoelectron spectroscopy of LBFCO ceramics show that cobalt dopant is bivalent as an acceptor, which induces an enhancement of oxygen vacancy concentration in LBFCO ceramics. Possible mechanisms for both resistive switching and threshold switching effects are discussed on the basis of the interplay of bound ferroelectric charges and mobile charged defects.

  16. Quantification of residual antibiotics in cow manure being spread over agricultural land and assessment of their behavioral effects on antibiotic resistant bacteria.

    PubMed

    Yeom, Ji-Ran; Yoon, Soon-Uk; Kim, Chang-Gyun

    2017-09-01

    Antibiotic resistant bacteria (ARB) in livestock manure used as fertilizer and spread over agriculture land, may pose a threat to the health of humans. Considering this, the concentrations of tetracycline (TC), oxytetracycline (OTC), and sulfathiazole (STZ) in the surface soil were quantified using LC-MS. These antibiotics have been used in livestock and are found in fertilizer produced from livestock excretions. Species of ABR were identified using 16S rDNA. Soil samples were collected at depths of 0, 7, and 15 cm from farmland in Incheon (South Korea). In the surface soil, three compounds were detected: TC (17.74 μg/kg), OTC (0.78 μg/kg), and STZ (0.23 μg/kg). However, except for STZ, antibiotics were not detected in the deeper samples. Overall, TC can form a chelated complex with cations, which consequently enhances its adsorption to the organic matter and metals in soil. This property can significantly reduce the mobility of TC (to lower than that of STZ). The result of 16S rDNA gene analysis indicated that Pseudomonas spp., Arthrobacter spp., and Rhodococcus spp. showed persistent resistance to the three antibiotics tested. DNA quantification results revealed strong resistance of Pseudomonas spp. to STZ, whereas Arthrobacter spp. and Rhodococcus spp. had resistance to TC and OTC. Antibiotics biodegradation suggested ability of ARB to grow in soil samples in presence of residual antibiotics during 13 days incubation. The concentrations of STZ, TC, and OTC reduced as much as 23.53, 35.60 and 66.88%, respectively. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Mobility dynamics of migrant workers and their socio-behavioral parameters related to malaria in Tier II, Artemisinin Resistance Containment Zone, Myanmar.

    PubMed

    Hlaing, Thaung; Wai, Khin Thet; Oo, Tin; Sint, Nyan; Min, Tun; Myar, Shwe; Lon, Khin Nan; Naing, Myo Myint; Tun, Tet Toe; Maung, Nay Lin Yin; Galappaththy, Gawrie N L; Thimarsan, Krongthong; Wai, Tin Tin; Thaung, Lwin Ni Ni

    2015-09-14

    Areas with dynamic population movements are likely to be associated with higher levels of drug-resistant malaria. Myanmar Artemisinin Resistance Containment (MARC) Project has been launching since 2012. One of its components includes enhancing strategic approaches for mobile/migrant populations. We aimed to ascertain the estimated population of mobile migrant workers and their families in terms of stability in work setting in townships classified as tier II (areas with significant inflows of people from areas with credible evidence of artemisinin resistance) for Artemisinin resistance; to identify knowledge, attitudes and practices related to prevention and control of malaria and to recommend cost-effective strategies in planning for prevention and control of malaria. A prospective cross-sectional study conducted between June to December 2013 that covered 1,899 migrant groups from 16 tier II townships of Bago Region, and Kayin and Kayah States. Trained data collectors used a pre-tested and subsequently modified questionnaire and interviewed 2,381 respondents. Data of migrant groups were analyzed and compared by category depending upon the stability of their work setting. The estimated population of the 1,899 migrant groups categorized into three on the nature of their work setting was 56,030. Bago region was the commonest reported source of origin of migrant groups as well as their transit. Malaria volunteers were mostly within the reach of category 1 migrant groups (43/66, 65.2 %). Less stable migrant groups in category 3 had limited access to malaria information (14.7 %) and malaria care providers (22.1 %), low level of awareness and use of long-lasting insecticide-treated nets (46.6 and 38.8 %). Also, they had poor knowledge on malaria prevention on confirming suspected malaria and on using artemisinin combined therapy (ACT). Within two weeks prior to the survey, only 16.5 % of respondents in all categories combined reported acute undifferentiated fever

  18. Stop Thinking and Start Doing: Switching from Cognitive Therapy to Behavioral Activation in a Case of Chronic Treatment-Resistant Depression

    ERIC Educational Resources Information Center

    Bottonari, Kathryn A.; Roberts, John E.; Thomas, Sherilyn N.; Read, Jennifer P.

    2008-01-01

    Several recent investigations have demonstrated that Cognitive Therapy (CT) and Behavioral Activation (BA) are both efficacious treatments for depression (Butler, Chapman, Forman, & Beck, 2006; Dimidjian et al., 2006; Dobson, 1989; Gloaguen, Cottraux, Cucherat, & Blackburn, 1998; Hollon, Thase, & Markowitz, 2002; Jacobson et al., 1996). This…

  19. Stop Thinking and Start Doing: Switching from Cognitive Therapy to Behavioral Activation in a Case of Chronic Treatment-Resistant Depression

    ERIC Educational Resources Information Center

    Bottonari, Kathryn A.; Roberts, John E.; Thomas, Sherilyn N.; Read, Jennifer P.

    2008-01-01

    Several recent investigations have demonstrated that Cognitive Therapy (CT) and Behavioral Activation (BA) are both efficacious treatments for depression (Butler, Chapman, Forman, & Beck, 2006; Dimidjian et al., 2006; Dobson, 1989; Gloaguen, Cottraux, Cucherat, & Blackburn, 1998; Hollon, Thase, & Markowitz, 2002; Jacobson et al., 1996). This…

  20. Employee Resistance to Computer Technology.

    ERIC Educational Resources Information Center

    Ewert, Alan

    1984-01-01

    The introduction of computers to the work place may cause employee stress. Aggressive, protective, and avoidance behaviors are forms of staff resistance. The development of good training programs will enhance productivity. Suggestions for evaluating computer systems are offered. (DF)

  1. Employee Resistance to Computer Technology.

    ERIC Educational Resources Information Center

    Ewert, Alan

    1984-01-01

    The introduction of computers to the work place may cause employee stress. Aggressive, protective, and avoidance behaviors are forms of staff resistance. The development of good training programs will enhance productivity. Suggestions for evaluating computer systems are offered. (DF)

  2. Metabolic Resistance in Bed Bugs

    PubMed Central

    Mamidala, Praveen; Jones, Susan C.; Mittapalli, Omprakash

    2011-01-01

    Blood-feeding insects have evolved resistance to various insecticides (organochlorines, pyrethroids, carbamates, etc.) through gene mutations and increased metabolism. Bed bugs (Cimex lectularius) are hematophagous ectoparasites that are poised to become one of the major pests in households throughout the United States. Currently, C. lectularius has attained a high global impact status due to its sudden and rampant resurgence. Resistance to pesticides is one factor implicated in this phenomenon. Although much emphasis has been placed on target sensitivity, little to no knowledge is available on the role of key metabolic players (e.g., cytochrome P450s and glutathione S-transferases) towards pesticide resistance in C. lectularius. In this review, we discuss different modes of resistance (target sensitivity, penetration resistance, behavioral resistance, and metabolic resistance) with more emphasis on metabolic resistance. PMID:26467498

  3. Metabolic Resistance in Bed Bugs.

    PubMed

    Mamidala, Praveen; Jones, Susan C; Mittapalli, Omprakash

    2011-03-18

    Blood-feeding insects have evolved resistance to various insecticides (organochlorines, pyrethroids, carbamates, etc.) through gene mutations and increased metabolism. Bed bugs (Cimex lectularius) are hematophagous ectoparasites that are poised to become one of the major pests in households throughout the United States. Currently, C. lectularius has attained a high global impact status due to its sudden and rampant resurgence. Resistance to pesticides is one factor implicated in this phenomenon. Although much emphasis has been placed on target sensitivity, little to no knowledge is available on the role of key metabolic players (e.g., cytochrome P450s and glutathione S-transferases) towards pesticide resistance in C. lectularius. In this review, we discuss different modes of resistance (target sensitivity, penetration resistance, behavioral resistance, and metabolic resistance) with more emphasis on metabolic resistance.

  4. BEHAVIORAL MANAGEMENT OF HYPOCHONDRIASIS

    PubMed Central

    Revar, J.M.

    1993-01-01

    SUMMARY In general medical practice, hypochondriasis is present in 3 to 14 percent of patients. This condition is reported as being resistant to treatment. In this paper, behavioral intervention in an adult male with hypochondriasis is outlined The management involved progressive relaxation, behavioral counseling and bibliotherapy. PMID:21743656

  5. Parental mind-mindedness but not false belief understanding predicts Hong Kong children's lie-telling behavior in a temptation resistance task.

    PubMed

    Wang, Lamei; Zhu, Liqi; Wang, Zhenlin

    2017-10-01

    Children can tell lies before they understand the concept of false belief. This study investigated the relationship between parental mind-mindedness, defined as the propensity of parents to view their children as mental agents with independent thoughts and feelings, and the lie-telling behavior of Hong Kong children aged 3-6years. The results confirmed earlier findings indicating that Hong Kong children's understanding of false belief is delayed; nevertheless, the participants appeared to lie just as well as children from other cultures. The lie-telling behavior of Hong Kong children was predicted by parental mind-mindedness and children's age but was unrelated to children's false belief understanding. It is suggested that children of mind-minded parents are more likely to exercise autonomy in socially ambiguous situations. Future studies should focus on the roles of parenting and children's multifaceted autonomy when addressing children's adaptive lie telling. Copyright © 2017 Elsevier Inc. All rights reserved.

  6. Hearing the Resistance.

    ERIC Educational Resources Information Center

    Malinconico, S. Michael

    1983-01-01

    Proposes the "congruence model" as a theoretical framework for assessing the effects on organizational behavior of changes based on modern electronic technology. The nature and causes of resistance, encroachment on professional judgement, and unwillingness to deviate from standard practice when using online systems are discussed. Sixteen…

  7. Behavior of tetracycline and sulfamethoxazole and their corresponding resistance genes in three-dimensional biofilm-electrode reactors with low current.

    PubMed

    Zhang, Shuai; Song, Hai L; Yang, Xiao L; Long, Xi Z; Liu, Xi; Chen, Tong Q

    2017-03-21

    Antibiotics and antibiotic resistance genes (ARGs) have become major health concerns. In this study, three-dimensional biofilm-electrode reactors (3D-BERs) under low current were designed to assess their performance in removing tetracycline (TC) and sulfamethoxazole (SMX) from synthetic wastewater. In addition, the fates of the corresponding ARGs in microbial communities were investigated. The mass removal ratios of TC and SMX by the 3D-BERs were 82.6-97.3% and 72.2-93.2%, respectively. There were obvious increases in the relative abundances of all target genes after ∼2 months. The tet and sul genes were significantly upregulated by high concentrations of antibiotics in the cathode layer, and higher ARG levels were evident in the cathodes than in the anodes. High-throughput sequencing identified Methylotenera, Candidatus Accumulibacter, Limnohabitans, Dechloromonas, Crenothrix, and Caldilinea as the dominant genera in the samples at the end of the experiment, after ∼8 months, and these bacteria potentially exhibited antibiotic resistance. The relative abundances and compositions of the dominant microbial populations changed throughout the course of antibiotic removal in the 3D-BERs.

  8. Overcoming resistance to organizational change.

    PubMed

    Henry, P K

    1997-10-01

    Resistance to assertive organization change is inevitable because people are asked to reexamine and modify their behavior, which breeds resistance. Resistance serves to maintain equilibrium until the reasons for change are both conscious and compelling. Instead of accepting people's feelings as excuses, persistently push for what you know needs to happen in the face of today's harsh realities. Provide clarity, time, support, and the stability of a persistent message.

  9. Diminishing sign anomaly and scaling behavior of the mixed-state Hall resistivity in Tl2Ba2Ca2Cu3O10 films containing columnar defects

    NASA Technical Reports Server (NTRS)

    Budhani, R. C.; Liou, S. H.; Cai, Z. X.

    1993-01-01

    The issues of sign reversal of the Hall voltage and scaling between longitudinal (rho(xx)) and Hall (rho(xy)) resistivities are studied in Tl2Ba2Ca2Cu3O10 films in which the vortex dynamics is drastically changed by flux pinning at heavy-ion-irradiation-induced linear defects. While the sign anomaly diminishes with increasing defect concentration, the power law rho(xy) is approximately equal to rho(xx) exp beta, beta = 1.85 +/- 0.1, holds even after irradiation. This result shows that the scaling is a universal feature of the mixed state in this system. The sign anomaly, on the other hand, is not consistent with a model that invokes pinning-induced backflow in the vortex core as the mechanism for this effect.

  10. Oxygen loss, semiconductivity, and positive temperature coefficient of resistance behavior in undoped cation-stoichiometric BaTiO3 ceramics

    NASA Astrophysics Data System (ADS)

    Beltrán, H.; Cordoncillo, E.; Escribano, P.; Sinclair, D. C.; West, A. R.

    2005-11-01

    Stoichiometric BaTiO3 ceramics fabricated from sol-gel-derived powders and sintered at temperatures <=1100 °C are highly insulating and electrically homogeneous. At higher sintering temperatures, samples gradually lose oxygen and the conductivity increases as a consequence. The latter phenomena are very sensitive to the furnace atmosphere and are partially reversible during cooling when partial reoxidation can occur. This results in ceramics that are often electrically heterogeneous with insulating surfaces or grain boundaries but semiconducting grain cores. In samples that were heated at 1450 °C in N2 and quenched, a positive temperature coefficient of resistance (PTCR) effect was observed, associated with an additional impedance arising from space-charge effects. These results demonstrate that, depending on sample processing, insulating cation-stoichiometric BaTiO3 can instead be semiconducting and under certain circumstances, exhibit a PTCR effect, without the need for donor dopant additives.

  11. Diminishing sign anomaly and scaling behavior of the mixed-state Hall resistivity in Tl2Ba2Ca2Cu3O10 films containing columnar defects

    NASA Technical Reports Server (NTRS)

    Budhani, R. C.; Liou, S. H.; Cai, Z. X.

    1993-01-01

    The issues of sign reversal of the Hall voltage and scaling between longitudinal (rho(xx)) and Hall (rho(xy)) resistivities are studied in Tl2Ba2Ca2Cu3O10 films in which the vortex dynamics is drastically changed by flux pinning at heavy-ion-irradiation-induced linear defects. While the sign anomaly diminishes with increasing defect concentration, the power law rho(xy) is approximately equal to rho(xx) exp beta, beta = 1.85 +/- 0.1, holds even after irradiation. This result shows that the scaling is a universal feature of the mixed state in this system. The sign anomaly, on the other hand, is not consistent with a model that invokes pinning-induced backflow in the vortex core as the mechanism for this effect.

  12. Behavioral response of pyrite structured Co0.2Fe0.8S2 nano-wires under high-pressure up to 8 GPa - Mössbauer spectroscopic and electrical resistivity studies

    NASA Astrophysics Data System (ADS)

    Chandra, U.; Sharma, P.; Parthasarathy, G.; Sreedhar, B.

    2016-02-01

    Pyrite-structured Co0.2Fe0.8S2 nano wires with aspect ratio 45:1, synthesized using solution colloid method were studied under high pressure up to 8 GPa using 57Fe Mössbauer spectroscopy (using diamond anvil cell) and electrical resistivity (using tungsten carbide cell) techniques. Room temperature S K-edge XANES studies at INFN-LNF synchrotron beam line signified the changes in the electronic structure owing to Co substitution. Magnetic measurements at 5 K demonstrated disordered ferromagnetic behavior similar to Griffith phase. The value of isomer shift identified Fe in divalent, low spin state corresponding to pyrite structure. Higher value of quadrupole splitting observed at ambient condition was due to large lattice strain and electric field gradient generated by large surface to volume ratio of the nano size of the system. With applied pressure, the value followed the expected trend of increase up to 4.3 GPa, then to decrease till 6.4 GPa. Such change in the trend suggested a phase transition. On decompression to ambient pressure, the system seemed to retain high pressure phase and nano structure. The pressure coefficient of electrical resistivity varying from -0.0454 to -0.166 Ω-cm/GPa across the transition pressure of ~4.5 GPa was sluggish suggesting second order phase transition. The pressure-dependent variations by Mössbauer parameters and electrical resistivity showed identical result. This is the first report of pressure effect on nano sized Co0.2Fe0.8S2. Effect of particle size on transition pressure could not be evaluated due to lack of available reports on bulk system.

  13. Epidemiologic Behavior and Estimation of an Optimal Cut-Off Point for Homeostasis Model Assessment-2 Insulin Resistance: A Report from a Venezuelan Population

    PubMed Central

    Bermúdez, Valmore; Martínez, María Sofía; Apruzzese, Vanessa; Chávez-Castillo, Mervin; Gonzalez, Robys; Torres, Yaquelín; Bello, Luis; Añez, Roberto; Chacín, Maricarmen; Toledo, Alexandra; Cabrera, Mayela; Mengual, Edgardo; Ávila, Raquel; López-Miranda, José

    2014-01-01

    Background. Mathematical models such as Homeostasis Model Assessment have gained popularity in the evaluation of insulin resistance (IR). The purpose of this study was to estimate the optimal cut-off point for Homeostasis Model Assessment-2 Insulin Resistance (HOMA2-IR) in an adult population of Maracaibo, Venezuela. Methods. Descriptive, cross-sectional study with randomized, multistaged sampling included 2,026 adult individuals. IR was evaluated through HOMA2-IR calculation in 602 metabolically healthy individuals. For cut-off point estimation, two approaches were applied: HOMA2-IR percentile distribution and construction of ROC curves using sensitivity and specificity for selection. Results. HOMA2-IR arithmetic mean for the general population was 2.21 ± 1.42, with 2.18 ± 1.37 for women and 2.23 ± 1.47 for men (P = 0.466). When calculating HOMA2-IR for the healthy reference population, the resulting p75 was 2.00. Using ROC curves, the selected cut-off point was 1.95, with an area under the curve of 0.801, sensibility of 75.3%, and specificity of 72.8%. Conclusions. We propose an optimal cut-off point of 2.00 for HOMA2-IR, offering high sensitivity and specificity, sufficient for proper assessment of IR in the adult population of our city, Maracaibo. The determination of population-specific cut-off points is needed to evaluate risk for public health problems, such as obesity and metabolic syndrome. PMID:27379332

  14. Microstructure and wear behaviors of laser clad NiCr/Cr3C2-WS2 high temperature self-lubricating wear-resistant composite coating

    NASA Astrophysics Data System (ADS)

    Yang, Mao-Sheng; Liu, Xiu-Bo; Fan, Ji-Wei; He, Xiang-Ming; Shi, Shi-Hong; Fu, Ge-Yan; Wang, Ming-Di; Chen, Shu-Fa

    2012-02-01

    The high temperature self-lubricating wear-resistant NiCr/Cr3C2-30%WS2 coating and wear-resistant NiCr/Cr3C2 coating were fabricated on 0Cr18Ni9 austenitic stainless steel by laser cladding. Phase constitutions and microstructures were investigated, and the tribological properties were evaluated using a ball-on-disc wear tester under dry sliding condition at room-temperature (17 °C), 300 °C and 600 °C, respectively. Results indicated that the laser clad NiCr/Cr3C2 coating consisted of Cr7C3 primary phase and γ-(Fe,Ni)/Cr7C3 eutectic colony, while the coating added with WS2 was mainly composed of Cr7C3 and (Cr,W)C carbides, with the lubricating WS2 and CrS sulfides as the minor phases. The wear tests showed that the friction coefficients of two coatings both decrease with the increasing temperature, while the both wear rates increase. The friction coefficient of laser clad NiCr/Cr3C2-30%WS2 is lower than the coating without WS2 whatever at room-temperature, 300 °C, 600 °C, but its wear rate is only lower at 300 °C. It is considered that the laser clad NiCr/Cr3C2-30%WS2 composite coating has good combination of anti-wear and friction-reducing capabilities at room-temperature up to 300 °C.

  15. QCM-4, a 5-HT₃ receptor antagonist ameliorates plasma HPA axis hyperactivity, leptin resistance and brain oxidative stress in depression and anxiety-like behavior in obese mice.

    PubMed

    Kurhe, Yeshwant; Mahesh, Radhakrishnan; Devadoss, Thangaraj

    2015-01-02

    Several preclinical studies have revealed antidepressant and anxiolytic-like effect of 5-HT3 receptor antagonists. In our earlier study, we have reported the antidepressive-like effect of 3-methoxy-N-p-tolylquinoxalin-2-carboxamide (QCM-4) in obese mice subjected to chronic stress. The present study deals with the biochemical mechanisms associated with depression co-morbid with obesity. Mice were fed with high fat diet (HFD) for 14 weeks, further subjected for treatment with QCM-4 (1 and 2mg/kg p.o.) and standard antidepressant escitalopram (ESC) (10mg/kg p.o.) for 28 days. Behavioral assays for depression such as sucrose preference test (SPT), forced swim test (FST) and for anxiety such as light and dark test (LDT) and hole board test (HBT) were performed in obese mice. Biochemical assessments including plasma leptin and corticosterone concentration followed by brain oxidative stress parameters malonaldehyde (MDA) and reduced glutathione (GSH) were performed. Results confirmed that QCM-4 exhibits antidepressive effect by increasing the sucrose consumption in SPT, reducing immobility time in FST and anxiolytic effect by increasing transitions and time in light chamber in LDT, increasing head dip and crossing score in HBT. Furthermore, QCM-4 attenuated the hypothalamic-pituitary-adrenal (HPA) axis hyperactivity by reducing the plasma corticosterone, reversing altered plasma leptin, restoring the imbalance of brain MDA and GSH concentration. In conclusion, QCM-4 showed antidepressive and anxiolytic effect by reversing the behavioral alterations that were supported by biochemical estimations in obese mice.

  16. Resistance to Disruption in a Classroom Setting

    ERIC Educational Resources Information Center

    Parry-Cruwys, Diana E.; Neal, Carrie M.; Ahearn, William H.; Wheeler, Emily E.; Premchander, Raseeka; Loeb, Melissa B.; Dube, William V.

    2011-01-01

    Substantial experimental evidence indicates that behavior reinforced on a denser schedule is more resistant to disruption than is behavior reinforced on a thinner schedule. The present experiment studied resistance to disruption in a natural educational environment. Responding during familiar activities was reinforced on a multiple…

  17. The Role of Residual Casting Solvent in Determining the Lithographic and Dissolution Behavior of Poly(methyl Methacrylate), a Positive Electron Beam Resist.

    NASA Astrophysics Data System (ADS)

    Criss, Robert Randolph, Jr.

    The effect of the pre-exposure bake and the choice of casting solvent on the sensitivity and contrast of PMMA has been documented to an extent not previously reported in the literature. PMMA films were spin cast onto clean silicon substrates from chlorobenzene and tri-chloroethylene solutions. The temperature of the pre-bake was varied over the range of 59^circ to 170^circC using a convection oven with pre-bake times ranging from 30 to 90 minutes. At the end of the designated bake time, the films were removed from the oven and allowed to cool in a temperature and humidity controlled environment. They were promptly exposed to a 15 KeV electron beam, then developed, with mild agitation, in a 1:1 mixture of MIBK and IPA at 22.5^ circC. Film thickness profiles were determined with an alpha-step profilometer. Films baked at temperatures below T_{rm glass} (the temperature which marks the onset of long-range, coordinated molecular motion), exhibited improved sensitivity and poorer contrast when compared to those baked above T_{rm glass }. Unique to this work is the finding that the lithographic performance depends on the choice of casting solvent, even at pre-bake temperatures significantly above T_{rm glass}. The relative concentrations of the casting solvents remaining in the baked films was determined from UV absorption spectra. The dissolution rates of exposed films were also measured and compared to the fragmented molecular weight model of development. Energy depositions were calculated from the empirical model of Everhart and Hoff. Cross-correlation of these results indicate that the pre-bake temperature more strongly correlates with the observed improvement in sensitivity than the presence of residual casting solvent. Residual casting solvent changes the density of the film, thus changing the energy deposition and dissolution behavior. Calculations based on the aforementioned models indicate that the observed lithographic and dissolution behavior can not be

  18. Comprehensive study of the abrasive wear and slurry erosion behavior of an expanded system of high chromium cast iron and microstructural modification for enhanced wear resistance

    NASA Astrophysics Data System (ADS)

    Chung, Reinaldo Javier

    High chromium cast irons (HCCIs) have been demonstrated to be an effective material for a wide range of applications in aggressive environments, where resistances to abrasion, erosion and erosion-corrosion are required. For instance, machinery and facilities used in mining and extraction in Alberta's oil sands suffer from erosion and erosion-corrosion caused by silica-containing slurries, which create challenges for the reliability and maintenance of slurry pumping systems as well as other processing and handling equipment. Considerable efforts have been made to determine and understand the relationship between microstructural features of the HCCIs and their wear performance, in order to guide the material selection and development for specific service conditions with optimal performance. The focus was previously put on a narrow group of compositions dictated by ASTM A532. However, with recent advances in casting technology, the HCCI compositional range can be significantly expanded, which potentially brings new alloys that can be superior to those which are currently employed. This work consists of three main aspects of study. The first one is the investigation of an expanded system of white irons with their composition ranging from 1 to 6 wt.% C and 5 to 45 wt.% Cr, covering 53 alloys. This work has generated wear and corrosion maps and established correlation between the performance and microstructural features for the alloys. The work was conducted in collaboration with the Materials Development Center of Weir Minerals in Australia, and the results have been collected in a database that is used by the company to guide materials selection for slurry pump components in Alberta oil sands and in other mining operations throughout the world. The second part consists of three case studies on effects of high chromium and high carbon, respectively, on the performance of the HCCIs. The third aspect is the development of an approach to enhance the wear resistance of

  19. Whence Resistance?

    PubMed Central

    Davies, Stephen W.; Metzger, Rosemarie; Swenson, Brian R.; Sawyer, Robert G.

    2015-01-01

    Abstract Background: Antimicrobial resistance results from a complex interaction between pathogenic and non-pathogenic bacteria, antimicrobial pressure, and genes, which together comprise the total body of potential resistance elements. The purpose of this study is to review and evaluate the importance of antimicrobial pressure on the development of resistance in a single surgical intensive care unit. Methods: We reviewed a prospectively collected dataset of all intensive care unit (ICU)-acquired infections in surgical and trauma patients over a 6-y period at a single hospital. Resistant gram-negative pathogens (rGNR) included those resistant to all aminoglycosides, quinolones, penicillins, cephalosporins, or carbapenems; resistant gram-positive infections (rGPC) included methicillin-resistant Staphylococcus aureus (MRSA) or vancomycin-resistant enterococci (VRE). Each resistant infection was evaluated for prior or concomitant antibiotic use, previous treatment for the same (non-resistant) organism, and concurrent infection with the same organism (genus and species, although not necessarily resistant) in another ICU patient. Results: Three hundred and thirty resistant infections were identified: 237 rGNR and 93 rGPC. Infections with rGNR occurred frequently while receiving antibiotic therapy (65%), including the sensitive form of the subsequent resistant pathogen (42.2%). Infections with rGPC were also likely to occur on antimicrobial therapy (50.6%). Treatment of a different patient for an infection with the same resistant pathogen in the ICU at the time of diagnosis, implying potential patient-to-patient transmission occurred more frequently with rGNR infections (38.8%). Conclusion: Antimicrobial pressure exerts a substantial effect on the development of subsequent infection. Our data demonstrate a high estimated rate of de novo emergence of resistance after treatment, which appears to be more common than patient-to-patient transmission. These data support

  20. Bacterial cheating limits antibiotic resistance

    NASA Astrophysics Data System (ADS)

    Xiao Chao, Hui; Yurtsev, Eugene; Datta, Manoshi; Artemova, Tanya; Gore, Jeff

    2012-02-01

    The widespread use of antibiotics has led to the evolution of resistance in bacteria. Bacteria can gain resistance to the antibiotic ampicillin by acquiring a plasmid carrying the gene beta-lactamase, which inactivates the antibiotic. This inactivation may represent a cooperative behavior, as the entire bacterial population benefits from removing the antibiotic. The cooperative nature of this growth suggests that a cheater strain---which does not contribute to breaking down the antibiotic---may be able to take advantage of cells cooperatively inactivating the antibiotic. Here we find experimentally that a ``sensitive'' bacterial strain lacking the plasmid conferring resistance can invade a population of resistant bacteria, even in antibiotic concentrations that should kill the sensitive strain. We observe stable coexistence between the two strains and find that a simple model successfully explains the behavior as a function of antibiotic concentration and cell density. We anticipate that our results will provide insight into the evolutionary origin of phenotypic diversity and cooperative behaviors.

  1. RESISTIVITY METHODS

    USDA-ARS?s Scientific Manuscript database

    Resistivity methods were among the first geophysical techniques developed. The basic concept originated with Conrad Schlumberger, who conducted the initial resistivity field tests in Normandy, France during 1912. The resistivity method, employed in its earliest and most conventional form, uses an ex...

  2. Correlation of Electrical Resistance to CMC Stress-Strain and Fracture Behavior Under High Heat-Flux Thermal and Stress Gradients

    NASA Technical Reports Server (NTRS)

    Appleby, Matthew; Morscher, Gregory; Zhu, Dongming

    2015-01-01

    Because SiCSiC ceramic matrix composites (CMCs) are under consideration for use as turbine engine hot-section components in extreme environments, it becomes necessary to investigate their performance and damage morphologies under complex loading and environmental conditions. Monitoring of electrical resistance (ER) has been shown as an effective tool for detecting damage accumulation of woven melt-infiltrated SiCSiC CMCs. However, ER change under complicated thermo-mechanical loading is not well understood. In this study a systematic approach is taken to determine the capabilities of ER as a relevant non-destructive evaluation technique for high heat-flux testing, including thermal gradients and localized stress concentrations. Room temperature and high temperature, laser-based tensile tests were conducted in which stress-dependent damage locations were determined using modal acoustic emission (AE) monitoring and compared to full-field strain mapping using digital image correlation (DIC). This information is then compared with the results of in-situ ER monitoring, post-test ER inspection and fractography in order to correlate ER response to convoluted loading conditions and damage evolution.

  3. Comparison of the effects of gamma radiation and low temperature hydrogen peroxide gas plasma sterilization on the molecular structure, fatigue resistance, and wear behavior of UHMWPE.

    PubMed

    Goldman, M; Pruitt, L

    1998-06-05

    The effects of gamma radiation and low temperature hydrogen peroxide gas plasma (HPGP) sterilization on structure and cyclic mechanical properties were examined for orthopedic grade ultra-high-molecular-weight polyethylene (UHMWPE) and compared to each other as well as to no sterilization (control). Density was monitored with a density gradient column and was found to be directly influenced by the sterilization method employed: Gamma radiation led to an increase, while plasma did not. Oxidation of the polymer was studied by observing changes in the carbonyl peak with Fourier transform infrared spectrometry and was found to be strongly affected by both gamma radiation and subsequent aging, while plasma sterilization had little effect. Gamma radiation resulted in embrittlement of the polymer and a decreased resistance to fatigue crack propagation. This mechanical degradation was a direct consequence of postradiation oxidation and molecular evolution of the polymer and was not observed in the plasma-sterilized polymer. Both gamma radiation and plasma sterilization led to improved wear performance of the UHMWPE compared to the nonsterile control material.

  4. Towards a behavioral vaccine: exposure to accessible temptation when self-regulation is endorsed enhances future resistance to similar temptations in children.

    PubMed

    de Boer, Cara; de Ridder, Denise; de Vet, Emely; Grubliauskiene, Aiste; Dewitte, Siegfried

    2015-03-01

    Access to temptation is blamed for the rising prevalence of obesity in children. A popular way to counter this is to restrict physical access to temptation. As restrictions cannot be widely applied and may have adverse long-term effects, we examine whether accessible temptations in situations that endorse self-regulation train self-regulation. Specifically, we design a method that enhances children's self-regulatory skills in the long term. In two studies, participants were exposed to temptation in phase one and their self-regulatory skills were measured in phase two. In Study 1, we endorsed self-regulation in the presence of accessible temptation for four consecutive days and measured consumption on the fifth day. In Study 2, we exposed children to temptation similarly and, in addition, manipulated temptation strength to show that being tempted is crucial for the skill to develop. Next, we measured saliva and preferences. The findings suggest that exposure to temptation in a situation that supports self-regulation leads to better resistance to temptations in later contexts of accessible temptation in girls, but not boys. Our findings suggest that interventions aiming at strengthening children's self-regulatory skills through controlled exposure to temptation might be a productive long-term strategy to reduce consumption of unhealthy food. © 2014 The International Association of Applied Psychology.

  5. Enhanced salt resistance in apple plants overexpressing a Malus vacuolar Na+/H+ antiporter gene is associated with differences in stomatal behavior and photosynthesis.

    PubMed

    Li, Chao; Wei, Zhiwei; Liang, Dong; Zhou, Shasha; Li, Yonghong; Liu, Changhai; Ma, Fengwang

    2013-09-01

    High salinity is a major abiotic factor that limits crop production. The dwarfing apple rootstock M.26 is sensitive to such stress. To obtain an apple that is adaptable to saline soils, we transformed this rootstock with a vacuolar Na(+)/H(+) antiporter, MdNHX1. Differences in salt tolerance between transgenic and wild-type (WT) rootstocks were examined under field conditions. We also compared differences when 'Naganofuji No. 2' apple was grafted onto these transgenic or WT rootstocks. Plants on the transgenic rootstocks grew well during 60 d of mild stress (100 mM NaCl) while the WT exhibited chlorosis, inhibited growth and even death. Compared with the untreated control, the stomatal density was greater in both non-grafted and grafted WT plants exposed to 200 mM NaCl. In contrast, that density was significantly decreased in leaves from grafted transgenic plants. At 200 mM NaCl, net photosynthesis, stomatal conductance, intercellular CO2 concentration, and chlorophyll contents were markedly reduced in the WT, whereas the declines in those values were only minor in similarly stressed transgenic plants. Therefore, we conclude that overexpressing plants utilize a better protective mechanism for retaining higher photosynthetic capacity. Furthermore, this contrast in tolerance and adaptability to stress is linked to differences in stomatal behavior and photosynthetic rates. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

  6. Resistance mechanisms

    PubMed Central

    Cag, Yasemin; Caskurlu, Hulya; Fan, Yanyan; Cao, Bin

    2016-01-01

    By definition, the terms sepsis and septic shock refer to a potentially fatal infectious state in which the early administration of an effective antibiotic is the most significant determinant of the outcome. Because of the global spread of resistant bacteria, the efficacy of antibiotics has been severely compromised. S. pneumonia, Escherichia coli (E. coli), Klebsiella, Acinetobacter, and Pseudomonas are the predominant pathogens of sepsis and septic shock. It is common for E. coli, Klebsiella, Acinetobacter and Pseudomonas to be resistant to multiple drugs. Multiple drug resistance is caused by the interplay of multiple resistance mechanisms those emerge via the acquisition of extraneous resistance determinants or spontaneous mutations. Extended-spectrum beta-lactamases (ESBLs), carbapenemases, aminoglycoside-modifying enzymes (AMEs) and quinolone resistance determinants are typically external and disseminate on mobile genetic elements, while porin-efflux mechanisms are activated by spontaneous modifications of inherited structures. Porin and efflux mechanisms are frequent companions of multiple drug resistance in Acinetobacter and P. aeruginosa, but only occasionally detected among E. coli and Klebsiella. Antibiotic resistance became a global health threat. This review examines the major resistance mechanisms of the leading microorganisms of sepsis. PMID:27713884

  7. Insecticide resistance and resistance mechanisms in bed bugs, Cimex spp. (Hemiptera: Cimicidae).

    PubMed

    Dang, Kai; Doggett, Stephen L; Veera Singham, G; Lee, Chow-Yang

    2017-06-29

    The worldwide resurgence of bed bugs [both Cimex lectularius L. and Cimex hemipterus (F.)] over the past two decades is believed in large part to be due to the development of insecticide resistance. The transcriptomic and genomic studies since 2010, as well as morphological, biochemical and behavioral studies, have helped insecticide resistance research on bed bugs. Multiple resistance mechanisms, including penetration resistance through thickening or remodelling of the cuticle, metabolic resistance by increased activities of detoxification enzymes (e.g. cytochrome P450 monooxygenases and esterases), and knockdown resistance by kdr mutations, have been experimentally identified as conferring insecticide resistance in bed bugs. Other candidate resistance mechanisms, including behavioral resistance, some types of physiological resistance (e.g. increasing activities of esterases by point mutations, glutathione S-transferase, target site insensitivity including altered AChEs, GABA receptor insensitivity and altered nAChRs), symbiont-mediated resistance and other potential, yet undiscovered mechanisms may exist. This article reviews recent studies of resistance mechanisms and the genes governing insecticide resistance, potential candidate resistance mechanisms, and methods of monitoring insecticide resistance in bed bugs. This article provides an insight into the knowledge essential for the development of both insecticide resistance management (IRM) and integrated pest management (IPM) strategies for successful bed bug management.

  8. [Psychological resistances of women to the principal female methods of contraception. Clinical classification].

    PubMed

    Wauty-Dancot, M C; Rucquoy, G

    1975-01-01

    According to the literature and to the experience of the authors gathered at the family department at the Louvain Faculty of Medicine, these psychological resistances may schematically be classified as follows: normative and socio-cultural resistances; medical resistances (wish of pregnancy, personality traits, narcissm, sexual and technical resistances); psychopathological resistances (unspecific neurotic behavior, phobias, hypochondriasis, obsessive-compulsive neurosis, character neurosis); secondary resistances.

  9. Whitefly resistance traits derived from the wild tomato Solanum pimpinellifolium affect the preference and feeding behavior of Bemisia tabaci and reduce the spread of Tomato yellow leaf curl virus.

    PubMed

    Rodríguez-López, M J; Garzo, E; Bonani, J P; Fereres, A; Fernández-Muñoz, R; Moriones, E

    2011-10-01

    Breeding of tomato genotypes that limit whitefly (Bemisia tabaci) access and feeding might reduce the spread of Tomato yellow leaf curl virus (TYLCV), a begomovirus (genus Begomovirus, family Geminiviridae) that is the causal agent of tomato yellow leaf curl disease. TYLCV is restricted to the phloem and is transmitted in a persistent manner by B. tabaci. The tomato breeding line ABL 14-8 was developed by introgressing type IV leaf glandular trichomes and secretion of acylsucroses from the wild tomato Solanum pimpinellifolium accession TO-937 into the genetic background of the whitefly- and virus-susceptible tomato cultivar Moneymaker. Results of preference bioassays with ABL 14-8 versus Moneymaker indicated that presence of type IV glandular trichomes and the production of acylsucrose deterred the landing and settling of B. tabaci on ABL 14-8. Moreover, electrical penetration graph studies indicated that B. tabaci adults spent more time in nonprobing activities and showed a reduced ability to start probing. Such behavior resulted in a reduced ability to reach the phloem. The superficial type of resistance observed in ABL 14-8 against B. tabaci probing significantly reduced primary and secondary spread of TYLCV.

  10. Implementing a patient education intervention about Methicillin-resistant Staphylococcus aureus prevention and effect on knowledge and behavior in veterans with spinal cord injuries and disorders: A pilot randomized controlled trial

    PubMed Central

    Evans, Charlesnika T.; Hill, Jennifer N.; Guihan, Marylou; Chin, Amy; Goldstein, Barry; Richardson, Michael S. A.; Anderson, Vicki; Risa, Kathleen; Kellie, Susan; Cameron, Kenzie A.

    2014-01-01

    Objectives To assess the feasibility and effect of a nurse-administered patient educational intervention about Methicillin-resistant Staphylococcus aureus (MRSA) prevention on knowledge and behavior of Veterans with spinal cord injuries and disorders (SCI/D). Design Blinded, block-randomized controlled pilot trial. Setting Two Department of Veterans Affairs (VA) SCI Centers. Participants Veterans were recruited March–September 2010 through referral by a healthcare provider from inpatient, outpatient, and residential care settings. Intervention Thirty participants were randomized to the nurse-administered intervention and 31 to the usual care group. The intervention included a brochure and tools to assist nurses in conducting the education. Outcome measures Pre- and post-intervention measurement of knowledge and behaviors related to MRSA and prevention strategies and feasibility measures related to implementation. Results Participants were primarily male (95.1%), white (63.9%), with tetraplegia (63.9%) and mean age and duration of injury of 64.3 and 20.5 years, respectively. The intervention groups mean knowledge score significantly increased between pre- and post-test (mean change score = 1.70, 95% confidence interval, CI 0.25–3.15) while the usual care groups score did not significantly change (mean change score = 1.45, 95% CI −0.08–2.98). However, the mean knowledge change between intervention and usual care groups was not significantly different (P = 0.81). Overall behavior scores did not significantly differ between treatment groups; however, the intervention group was more likely to report intentions to clean hands (90.0% vs. 64.5%, P = 0.03) and asking providers about MRSA status (46.7% vs. 16.1%, P = 0.01). Nurse educators reported that the quality of the intervention was high and could be implemented in clinical care. Conclusions A targeted educational strategy is feasible to implement in SCI/D clinical practices and may improve some

  11. Implementing a patient education intervention about Methicillin-resistant Staphylococcus aureus prevention and effect on knowledge and behavior in veterans with spinal cord injuries and disorders: a pilot randomized controlled trial.

    PubMed

    Evans, Charlesnika T; Hill, Jennifer N; Guihan, Marylou; Chin, Amy; Goldstein, Barry; Richardson, Michael S A; Anderson, Vicki; Risa, Kathleen; Kellie, Susan; Cameron, Kenzie A

    2014-03-01

    To assess the feasibility and effect of a nurse-administered patient educational intervention about Methicillin-resistant Staphylococcus aureus (MRSA) prevention on knowledge and behavior of Veterans with spinal cord injuries and disorders (SCI/D). Blinded, block-randomized controlled pilot trial. Two Department of Veterans Affairs (VA) SCI Centers. Veterans were recruited March-September 2010 through referral by a healthcare provider from inpatient, outpatient, and residential care settings. Thirty participants were randomized to the nurse-administered intervention and 31 to the usual care group. The intervention included a brochure and tools to assist nurses in conducting the education. Pre- and post-intervention measurement of knowledge and behaviors related to MRSA and prevention strategies and feasibility measures related to implementation. Participants were primarily male (95.1%), white (63.9%), with tetraplegia (63.9%) and mean age and duration of injury of 64.3 and 20.5 years, respectively. The intervention groups mean knowledge score significantly increased between pre- and post-test (mean change score = 1.70, 95% confidence interval, CI 0.25-3.15) while the usual care groups score did not significantly change (mean change score = 1.45, 95% CI -0.08-2.98). However, the mean knowledge change between intervention and usual care groups was not significantly different (P = 0.81). Overall behavior scores did not significantly differ between treatment groups; however, the intervention group was more likely to report intentions to clean hands (90.0% vs. 64.5%, P = 0.03) and asking providers about MRSA status (46.7% vs. 16.1%, P = 0.01). Nurse educators reported that the quality of the intervention was high and could be implemented in clinical care. A targeted educational strategy is feasible to implement in SCI/D clinical practices and may improve some participants' knowledge about MRSA and increase intentions to improve hand hygiene and engagement with providers

  12. Antibiotic Resistance

    MedlinePlus

    ... are even stronger. Bacteria and Viruses Questions about Antibiotic Resistance Bacteria and Viruses Bacteria and viruses are the two ... even help us to digest food. But other bacteria cause bad diseases like TB and lyme disease. Questions about Antibiotic Resistance Does this affect me? If you have a ...

  13. Macrolide resistance.

    PubMed

    Weisblum, B

    1998-03-01

    The macrolides have evolved through four chemical generations since erythromycin became available for clinical use in 1952. The first generation, the 14-membered ring macrolide erythromycin, induced resistance and was replaced by the second generation 16-membered ring macrolides which did not. The inability to induce came at the price of mutation, in the pathogenic target strain, to constitutive expression of resistance. A third generation of macrolides improved the acid-stability, and therefore the pharmacokinetics of erythromycin, extending the clinical use of macrolides to Helicobacter pylori and Mycobacterium tuberculosis. Improved pharmacokinetics resulted in the selection of intrinsically resistant mutant strains with rRNA structural alterations. Expression of resistance in these strains was unexpected, explainable by low rRNA gene copy number which made resistance dominant. A fourth generation of macrolides, the 14-membered ring ketolides are the most recent development. Members of this generation are reported to be effective against inducibly resistant strains, and ketolide resistant strains have not yet been reported. In this review we discuss details of the ways in which bacteria have become resistant to the first three generations of macrolides, both with respect to their biochemistry, and the genetic mechanisms by which their expression is regulated.

  14. Genetic resistances

    USDA-ARS?s Scientific Manuscript database

    Genetic resistance often has been recognized as the most viable mean for limiting soil-borne diseases. In sugar beet, it is only for Beet necrotic yellow vein virus, i.e., rhizomania that a set of fairly different and effective, single-gene resistance is currently available, while for other soil-bor...

  15. CONTROLLING BEHAVIOR CHANGERS' BEHAVIOR.

    ERIC Educational Resources Information Center

    MARKLE, DAVID G.

    AN EMERGING METHODOLOGY OF PROGRAMING AVOIDS SOME OF THE UNFORTUNATE EFFECTS ON PROGRAMER BEHAVIOR PRODUCED BY INTERPRETATIONS OF TWO EARLIER METHODOLOGIES. WHILE SKINNERIAN PROGRAMING OFTEN HAS LED TO TRIVIAL PROGRAMS THROUGH PROBLEMS OF APPLICATION OF THE CRITERIA OF SPECIFIED BEHAVIORAL OBJECTIVES AND LOW ERROR RATES, CROWDERIAN PROGRAMING HAS…

  16. Multistate resistive switching in silver nanoparticle films

    PubMed Central

    Sandouk, Eric J; Gimzewski, James K; Stieg, Adam Z

    2015-01-01

    Resistive switching devices have garnered significant consideration for their potential use in nanoelectronics and non-volatile memory applications. Here we investigate the nonlinear current–voltage behavior and resistive switching properties of composite nanoparticle films comprising a large collective of metal–insulator–metal junctions. Silver nanoparticles prepared via the polyol process and coated with an insulating polymer layer of tetraethylene glycol were deposited onto silicon oxide substrates. Activation required a forming step achieved through application of a bias voltage. Once activated, the nanoparticle films exhibited controllable resistive switching between multiple discrete low resistance states that depended on operational parameters including the applied bias voltage, temperature and sweep frequency. The films’ resistance switching behavior is shown here to be the result of nanofilament formation due to formative electromigration effects. Because of their tunable and distinct resistance states, scalability and ease of fabrication, nanoparticle films have a potential place in memory technology as resistive random access memory cells. PMID:27877824

  17. Resistance to disruption in a classroom setting.

    PubMed

    Parry-Cruwys, Diana E; Neal, Carrie M; Ahearn, William H; Wheeler, Emily E; Premchander, Raseeka; Loeb, Melissa B; Dube, William V

    2011-01-01

    Substantial experimental evidence indicates that behavior reinforced on a denser schedule is more resistant to disruption than is behavior reinforced on a thinner schedule. The present experiment studied resistance to disruption in a natural educational environment. Responding during familiar activities was reinforced on a multiple variable-interval (VI) 7-s VI 30-s schedule for 6 participants with developmental disabilities. Resistance to disruption was measured by presenting a distracting item. Response rates in the disruption components were compared to within-session response rates in prior baseline components. Results were consistent with the predictions of behavioral momentum theory for 5 of 6 participants.

  18. Resisting HRD's Resistance to Diversity

    ERIC Educational Resources Information Center

    Bierema, Laura L.

    2010-01-01

    Purpose: The purpose of this paper is to empirically illustrate how human resource development (HRD) resists and omits issues of diversity in academic programs, textbooks, and research; analyze the research on HRD and diversity over a ten-year period; discuss HRD's resistance to diversity; and offer some recommendations for a more authentic…

  19. Resistivity analysis

    DOEpatents

    Bruce, Michael R.; Bruce, Victoria J.; Ring, Rosalinda M.; Cole, Edward Jr. I.; Hawkins, Charles F.; Tangyungong, Paiboon

    2006-06-13

    According to an example embodiment of the present invention a semiconductor die having a resistive electrical connection is analyzed. Heat is directed to the die as the die is undergoing a state-changing operation to cause a failure due to suspect circuitry. The die is monitored, and a circuit path that electrically changes in response to the heat is detected and used to detect that a particular portion therein of the circuit is resistive. In this manner, the detection and localization of a semiconductor die defect that includes a resistive portion of a circuit path is enhanced.

  20. Interface resistance

    NASA Astrophysics Data System (ADS)

    Sinkkonen, Juha

    1983-11-01

    Interface resistance is studied by using the Landauer formula which relates the resistance to the quantum mechanical transmission coefficient. A simple rederivation of the Landauer formula is given. Using a step-like potential barrier as a model for the metal-semiconductor contact an analytical expression for the effective Richardson constant is derived. As an other application the grain boundary resistance in polycrystalline semiconductors is studied. The short-range potential fluctuation associated with the grain boundary is described by a rectangular potential barrier. The results for the grain boundary limited mobility cover both the strong and weak scattering regimes.

  1. Spontaneously Hypertensive Rats (SHR) Are Resistant to a Reserpine-Induced Progressive Model of Parkinson’s Disease: Differences in Motor Behavior, Tyrosine Hydroxylase and α-Synuclein Expression

    PubMed Central

    Leão, Anderson H. F. F.; Meurer, Ywlliane S. R.; da Silva, Anatildes F.; Medeiros, André M.; Campêlo, Clarissa L. C.; Abílio, Vanessa C.; Engelberth, Rovena C. G. K.; Cavalcante, Jeferson S.; Izídio, Geison S.; Ribeiro, Alessandra M.; Silva, Regina H.

    2017-01-01

    Reserpine is an irreversible inhibitor of vesicular monoamine transporter-2 (VMAT2) used to study Parkinson’s disease (PD) and screening for antiparkinsonian treatments in rodents. Recently, the repeated treatment with a low-dose of reserpine was proposed as a progressive model of PD. Rats under this treatment show progressive catalepsy behavior, oral movements and spontaneous motor activity decrement. In parallel, compared to Wistar rats, spontaneously hypertensive rats (SHR) are resistant to acute reserpine-induced oral dyskinesia. We aimed to assess whether SHR would present differential susceptibility to repeated reserpine-induced deficits in the progressive model of PD. Male Wistar and SHR rats were administered 15 subcutaneously (s.c.) injections of reserpine (0.1 mg/kg) or vehicle, every other day and motor activity was assessed by the catalepsy, oral movements and open field tests. Only reserpine-treated Wistar rats presented increased latency to step down in the catalepsy test and impaired spontaneous activity in the open field. On the other hand, there was an increase in oral movements in both reserpine-treated strains, although with reduced magnitude and latency to instauration in SHR. After a 15-day withdrawn period, both strains recovered from motor impairment, but SHR animals expressed reduced latencies to reach control levels. Finally, we performed immunohistochemistry for tyrosine hydroxylase (TH) and α-synuclein (α-syn) 48 h after the last injection or 15 days after withdrawn. Reserpine-treated animals presented a reduction in TH and an increase in α-syn immunoreactivity in the substantia nigra and dorsal striatum (dSTR), which were both recovered after 15 days of withdraw. Furthermore, SHR rats were resistant to reserpine-induced TH decrement in the substantia nigra, and presented reduced immunoreactivity to α-syn in the dSTR relative to Wistar rats, irrespective of treatment. This effect was accompanied by increase of malondaldhyde (MDA) in

  2. Can early weight loss, eating behaviors and socioeconomic factors predict successful weight loss at 12- and 24-months in adolescents with obesity and insulin resistance participating in a randomised controlled trial?

    PubMed

    Gow, Megan L; Baur, Louise A; Ho, Mandy; Chisholm, Kerryn; Noakes, Manny; Cowell, Chris T; Garnett, Sarah P

    2016-04-01

    Lifestyle interventions in adolescents with obesity can result in weight loss following active intervention but individual responses vary widely. This study aimed to identify predictors of weight loss at 12- and 24-months in adolescents with obesity and clinical features of insulin resistance. Adolescents (n = 111, 66 girls, aged 10-17 years) were participants in a randomised controlled trial, the RESIST study, examining the effects of two diets differing in macronutrient content on insulin sensitivity. Eighty-five completed the 12-month program and 24-month follow-up data were available for 42 adolescents. Change in weight was determined by BMI expressed as a percentage of the 95th percentile (BMI95). The study physician collected socioeconomic data at baseline. Physical activity and screen time, and psychological dimensions of eating behavior were self-reported using the validated CLASS and EPI-C questionnaires, respectively. Stepwise multiple regressions were conducted to identify models that best predicted change in BMI95 at 12- and 24-months. Mean BMI95 was reduced at 12-months compared with baseline (mean difference [MD] ± SE: -6.9 ± 1.0, P < 0.001) but adolescents had significant re-gain from 12- to 24-months (MD ± SE: 3.7 ± 1.5, P = 0.017). Participants who achieved greater 12-month weight loss had: greater 3-month weight loss, a father with a higher education, lower baseline external eating and parental pressure to eat scores and two parents living at home. Participants who achieved greater 24-month weight loss had: greater 12-month weight loss and a lower baseline emotional eating score. Early weight loss is consistently identified as a strong predictor of long-term weight loss. This could be because early weight loss identifies those more motivated and engaged individuals. Patients who have baseline factors predictive of long-term weight loss failure may benefit from additional support during the intervention. Additionally

  3. Electrical resistivity anomaly, valence shift of Pr ion, and magnetic behavior in epitaxial (Pr1-yYy)1-xCaxCoO3 thin films under compressive strain

    NASA Astrophysics Data System (ADS)

    Fujishiro, H.; Noda, Y.; Akuzawa, K.; Naito, T.; Ito, A.; Goto, T.; Marysko, M.; Jirak, Z.; Hejtmanek, J.; Nitta, K.

    2017-03-01

    We have fabricated (Pr1-yYy)1-xCaxCoO3 (PYCCO) epitaxial films with various thicknesses by pulsed laser deposition on the SrLaAlO4 (SLAO) substrate that applied an in-plane compressive stress to the film, and investigated the temperature dependence of the electrical resistivity, ρ(T), of the films. An anomalous ρ(T) upturn with a broad hysteresis could be clearly observed only for the thinnest film (d = 50 nm), and the ρ(T) anomaly decreased by increasing film thickness, d. The temperature dependence of the X-ray absorption near-edge structure (XANES) spectra at Pr L2-edge was measured for the films, and the valence states of praseodymium (Pr) ion were determined using the analysis of the XANES spectra. As a result, the average valence of the Pr ion in the d = 50 nm film slightly increases with decreasing temperature from the common value of 3.0+ around room temperature to 3.15+ at 8 K. The valence shift of Pr is thus similar to what was observed on the PYCCO polycrystalline bulks with an abrupt metal-insulator transition, accompanied by a spin-state (SS) transition of Co ions. Furthermore, the low-temperature SQUID measurements evidenced a paramagnetic behavior down to the lowest temperature, which suggests that the dominant part of Co3+ ions in the film grown on the SLAO substrate tends to be in the low spin state characteristic for the insulating ground state. These results strongly suggest that the anomalous ρ(T) upturn in the thin films on the SrLaAlO4 (SLAO) substrate is closely related to the SS transition of Co ions. On the other hand, PYCCO films grown on the LaAlO3 (LAO) substrate that applied an in-plane tensile stress showed no valence shift of Pr ions and developed a long range ferromagnetic order, which points to a complete suppression of the low-temperature transition. The behaviors of the epitaxial films are discussed in terms of the in-plane stress exerted by different substrates and accumulated elastic energy.

  4. Lantibiotic resistance.

    PubMed

    Draper, Lorraine A; Cotter, Paul D; Hill, Colin; Ross, R Paul

    2015-06-01

    The dramatic rise in the incidence of antibiotic resistance demands that new therapeutic options will have to be developed. One potentially interesting class of antimicrobials are the modified bacteriocins termed lantibiotics, which are bacterially produced, posttranslationally modified, lanthionine/methyllanthionine-containing peptides. It is interesting that low levels of resistance have been reported for lantibiotics compared with commercial antibiotics. Given that there are very few examples of naturally occurring lantibiotic resistance, attempts have been made to deliberately induce resistance phenotypes in order to investigate this phenomenon. Mechanisms that hinder the action of lantibiotics are often innate systems that react to the presence of any cationic peptides/proteins or ones which result from cell well damage, rather than being lantibiotic specific. Such resistance mechanisms often arise due to altered gene regulation following detection of antimicrobials/cell wall damage by sensory proteins at the membrane. This facilitates alterations to the cell wall or changes in the composition of the membrane. Other general forms of resistance include the formation of spores or biofilms, which are a common mechanistic response to many classes of antimicrobials. In rare cases, bacteria have been shown to possess specific antilantibiotic mechanisms. These are often species specific and include the nisin lytic protein nisinase and the phenomenon of immune mimicry.

  5. Lantibiotic Resistance

    PubMed Central

    Draper, Lorraine A.; Ross, R. Paul

    2015-01-01

    SUMMARY The dramatic rise in the incidence of antibiotic resistance demands that new therapeutic options will have to be developed. One potentially interesting class of antimicrobials are the modified bacteriocins termed lantibiotics, which are bacterially produced, posttranslationally modified, lanthionine/methyllanthionine-containing peptides. It is interesting that low levels of resistance have been reported for lantibiotics compared with commercial antibiotics. Given that there are very few examples of naturally occurring lantibiotic resistance, attempts have been made to deliberately induce resistance phenotypes in order to investigate this phenomenon. Mechanisms that hinder the action of lantibiotics are often innate systems that react to the presence of any cationic peptides/proteins or ones which result from cell well damage, rather than being lantibiotic specific. Such resistance mechanisms often arise due to altered gene regulation following detection of antimicrobials/cell wall damage by sensory proteins at the membrane. This facilitates alterations to the cell wall or changes in the composition of the membrane. Other general forms of resistance include the formation of spores or biofilms, which are a common mechanistic response to many classes of antimicrobials. In rare cases, bacteria have been shown to possess specific antilantibiotic mechanisms. These are often species specific and include the nisin lytic protein nisinase and the phenomenon of immune mimicry. PMID:25787977

  6. Quantum criticality and DBI magneto-resistance

    NASA Astrophysics Data System (ADS)

    Kiritsis, Elias; Li, Li

    2017-03-01

    We use the DBI action from string theory and holography to study the magneto-resistance at quantum criticality with hyperscaling violation. We find and analyze a rich class of scaling behaviors for the magneto-resistance. A special case describes the scaling results found in pnictides by Hayers et al in 2014 (arXiv:1412.6484).

  7. Beyond Student Resistance: A Pedagogy of Possibility.

    ERIC Educational Resources Information Center

    Lindquist, Barbara

    1994-01-01

    Critiques the concept of resistance in interpreting students' behaviors and attitudes, examining political, social, and psychological connotations of resistance and contradictory ways that educators employ the concept. The paper explains limitations imposed on education by the concept, noting the work of educators who reassess the implications of…

  8. Androgen resistance.

    PubMed

    Hughes, Ieuan A; Deeb, Asma

    2006-12-01

    Androgen resistance causes the androgen insensitivity syndrome in its variant forms and is a paradigm of clinical syndromes associated with hormone resistance. In its complete form, the syndrome causes XY sex reversal and a female phenotype. Partial resistance to androgens is a common cause of ambiguous genitalia of the newborn, but a similar phenotype may result from several other conditions, including defects in testis determination and androgen biosynthesis. The biological actions of androgens are mediated by a single intracellular androgen receptor encoded by a gene on the long arm of the X chromosome. Mutations in this gene result in varying degrees of androgen receptor dysfunction and phenotypes that often show poor concordance with the genotype. Functional characterization and three-dimensional modelling of novel mutant receptors has been informative in understanding the mechanism of androgen action. Management issues in syndromes of androgen insensitivity include decisions on sex assignment, timing of gonadectomy in relation to tumour risk, and genetic and psychological counselling.

  9. Host plant resistance against tomato spotted wilt virus in peanut (Arachis hypogaea) and its impact on susceptibility to the virus, virus population genetics, and vector feeding behavior and survival.

    PubMed

    Sundaraj, Sivamani; Srinivasan, Rajagopalbabu; Culbreath, Albert K; Riley, David G; Pappu, Hanu R

    2014-02-01

    Tomato spotted wilt virus (TSWV) severely affects peanut production in the southeastern United States. Breeding efforts over the last three decades resulted in the release of numerous peanut genotypes with field resistance to TSWV. The degree of field resistance in these genotypes has steadily increased over time, with recently released genotypes exhibiting a higher degree of field resistance than older genotypes. However, most new genotypes have never been evaluated in the greenhouse or laboratory against TSWV or thrips, and the mechanism of resistance is unknown. In this study, TSWV-resistant and -susceptible genotypes were subjected to TSWV mechanical inoculation. The incidence of TSWV infection was 71.7 to 87.2%. Estimation of TSWV nucleocapsid (N) gene copies did not reveal significant differences between resistant and susceptible genotypes. Parsimony and principal component analyses of N gene nucleotide sequences revealed inconsistent differences between virus isolates collected from resistant and susceptible genotypes and between old (collected in 1998) and new (2010) isolates. Amino acid sequence analyses indicated consistent differences between old and new isolates. In addition, we found evidence for overabundance of nonsynonymous substitutions. However, there was no evidence for positive selection. Purifying selection, population expansion, and differentiation seem to have influenced the TSWV populations temporally rather than positive selection induced by host resistance. Choice and no-choice tests indicated that resistant and susceptible genotypes differentially affected thrips feeding and survival. Thrips feeding and survival were suppressed on some resistant genotypes compared with susceptible genotypes. These findings reveal how TSWV resistance in peanut could influence evolution, epidemiology, and management of TSWV.

  10. Culture and Disability Behavior

    PubMed Central

    Brodsky, Carroll M.

    1983-01-01

    A substantial amount of literature suggests that illness behavior in the United States is a product of a patient's core culture; equally credible findings do not support this contention. Most students and graduates in the health care professions believe that illness and disability behavior are affected by a patient's culture, but they are hard put to find convincing examples of that relationship. In experience with medical students studying the social and cultural bases of illness behavior, with patients who are disabled and with persons who claim disability in the absence of physical disease or disabling psychopathology, I observed no deviant disability behavior that was typical for the members of any cultural group, and no behavior was displayed by the members of one cultural group that was not seen in members of other cultural groups. No cultural stereotypes were upheld. I did find evidence that disability behavior is influenced by personality factors, social situations and the gains derived from the disability status. Evolving concepts of “entitlement,” which are closely related to socioeconomic status, also have a significant influence. The impact of feedback from others in a person's many social and medical subcultures is a more crucial determinant of illness and disability behavior, except in those for whom illness and disability behavior is determined by the limitations imposed by the disease or by a personality structure resistant to cultural expectations and social feedback. PMID:6666106

  11. Improving Maladaptive Behaviors Using Sensory Integration Techniques.

    ERIC Educational Resources Information Center

    Shuman, Theresa

    A study examined the use of sensory integration techniques to reduce the maladaptive behaviors that interfered with the learning of nine high school students with mental impairments attending a special school. Maladaptive behaviors identified included rocking, toe walking, echolalia, resistance to change, compulsive behaviors, aggression,…

  12. Drug Resistance

    USDA-ARS?s Scientific Manuscript database

    Drug resistance refers to both intrinsic and acquired abilities of cells or organisms to become insensitive or refractory to chemotherapeutic intervention. The advent of antibiotics is considered one of the most important medicinal developments in human history, which has led to significantly reduce...

  13. Resistive Networks.

    ERIC Educational Resources Information Center

    Balabanian, Norman

    This programed text on resistive networks was developed under contract with the United States Office of Education as part of a series of materials for use in an electrical engineering sequence. It is to be used in conjunction with other materials and with other short texts in the series, this one being Number 3. (DH)

  14. Cell shunt resistance and photovoltaic module performance

    SciTech Connect

    McMahon, T.J.; Basso, T.S.; Rummel, S.R.

    1996-09-01

    Shunt resistance of cells in photovoltaic modules can affect module power output and could indicate flawed manufacturing processes and reliability problems. The authors describe a two-terminal diagnostic method to directly measure the shunt resistance of individual cells in a series-connected module non-intrusively, without deencapsulation. Peak power efficiency vs. light intensity was measured on a 12-cell, series-connected, single crystalline module having relatively high cell shunt resistances. The module was remeasured with 0.5-, 1-, and 2-ohm resistors attached across each cell to simulate shunt resistances of several emerging technologies. Peak power efficiencies decreased dramatically at lower light levels. Using the PSpice circuit simulator, they verified that cell shunt and series resistances can indeed be responsible for the observed peak power efficiency vs. intensity behavior. They discuss the effect of basic cell diode parameters, i.e., shunt resistance, series resistance, and recombination losses, on PV module performance as a function of light intensity.

  15. Anthelmintic resistance.

    PubMed

    Waller, P J

    1997-11-01

    Since the first reports of resistance to the broad spectrum anthelmintics were made some three decades ago, this phenomenon has changed from being considered merely as a parasitological curiosity to a state of industry crisis in certain livestock sectors. This extreme situation exists with the small ruminant industry of the tropical/sub-tropical region of southern Latin America where resistance to the entire broad spectrum anthelmintic arsenal now occurs. In contrast, the cattle industry does not appear to be threatened--or so it seems. Although field reports of resistance have been made to the range of broad spectrum anthelmintics in nematode parasites of cattle, it appears that the evolution of resistance in cattle parasites is not as dramatic as for sheep worms. However, one cannot remain confident that this state of affairs will remain static. Concern is shared amongst parasitologists that we have not looked closely enough. In regions of the world where internal parasites are considered a problem in cattle and drenching occurs frequently, no widespread surveys have been carried out. It appears that because of the very high costs and risks associated with taking a new active drug down the development track to marketing, that the pharmaceutical industry has, in general, turned away from this activity. By implication, the international small ruminant industry is too small for these companies to make the necessary investment. This begs two questions: What is the fate of the sheep (and goat) industries in those parts of the world where resistance is rampant and immediate ameliorative parasite control options are required? What will be the response if significant resistance is found in cattle parasites? There is a body of opinion which suggests that if resistance becomes an issue in the control of cattle parasites then the pharmaceutical industry will find it commercially attractive to re-enter the anthelmintic discovery and development business. This is based on the

  16. The effect of a Ta oxygen scavenger layer on HfO2-based resistive switching behavior: Thermodynamic stability, electronic structure, and low-bias transport

    SciTech Connect

    Zhong, Xiaoliang; Rungger, Ivan; Zapol, Peter; Nakamura, Hisao; Asai, Yoshihiro; Heinonen, Olle

    2016-02-15

    Reversible resistive switching between high-resistance and low-resistance states in metal-oxide-metal heterostructures makes them very interesting for applications in random access memories. While recent experimental work has shown that inserting a metallic "oxygen scavenger layer'' between the positive electrode and oxide improves device performance, the fundamental understanding of how the scavenger layer modifies the heterostructure properties is lacking. We use density functional theory to calculate thermodynamic properties and conductance of TiN/HfO2/TiN heterostructures with and without a Ta scavenger layer. First, we show that Ta insertion lowers the formation energy of low-resistance states. Second, while the Ta scavenger layer reduces the Schottky barrier height in the high-resistance state by modifying the interface charge at the oxide-electrode interface, the heterostructure maintains a high resistance ratio between high-and low-resistance states. Lastly, we show that the low-bias conductance of device on-states becomes much less sensitive to the spatial distribution of oxygen removed from the HfO2 in the presence of the Ta layer. By providing a fundamental understanding of the observed improvements with scavenger layers, we open a path to engineer interfaces with oxygen scavenger layers to control and enhance device performance. In turn, this may enable the realization of a non-volatile low-power memory technology with concomitant reduction in energy consumption by consumer electronics and offering significant benefits to society.

  17. The Ritual Dimensions of Resistance: Clowning and Symbolic Inversion.

    ERIC Educational Resources Information Center

    McLaren, Peter L.

    1985-01-01

    Draws upon recent fieldwork in a Catholic junior high school to focus on the ritualized behavior of the "class clown," who resists instruction. Calls upon resistance theorists to strive for more conceptual precision in their articulation of the symbolic dimension of transgressive student behavior by utilizing a more multidisciplinary…

  18. The Ritual Dimensions of Resistance: Clowning and Symbolic Inversion.

    ERIC Educational Resources Information Center

    McLaren, Peter L.

    1985-01-01

    Draws upon recent fieldwork in a Catholic junior high school to focus on the ritualized behavior of the "class clown," who resists instruction. Calls upon resistance theorists to strive for more conceptual precision in their articulation of the symbolic dimension of transgressive student behavior by utilizing a more multidisciplinary…

  19. Student Resistance to Schooling: Disconnections with Education in Rural Appalachia

    ERIC Educational Resources Information Center

    Hendrickson, Katie A.

    2012-01-01

    This study investigates student reasons for resisting engagement with school in a rural Appalachian area. The concept of student resistance to school is considered within a White, working-class student population. Through classroom observations, students displaying resistant behaviors were selected to participate in interviews. Coding of interview…

  20. Student Resistance to Schooling: Disconnections with Education in Rural Appalachia

    ERIC Educational Resources Information Center

    Hendrickson, Katie A.

    2012-01-01

    This study investigates student reasons for resisting engagement with school in a rural Appalachian area. The concept of student resistance to school is considered within a White, working-class student population. Through classroom observations, students displaying resistant behaviors were selected to participate in interviews. Coding of interview…

  1. Behavioral dermatology.

    PubMed

    Virga, Vint

    2003-03-01

    The practice of behavioral dermatology encompasses the management of any dermatologic condition for which there is a substantial behavioral or emotional component. Commonly recognized behavioral dermatoses such as acral lick dermatitis, psychogenic alopecia, and hyperesthesia are syndromes rather than discrete diagnoses. Successful patient management is dependent upon integrating physiological, social, and environmental factors which contribute to the clinical manifestation of behavioral dermatoses.

  2. Pre-resistance-welding resistance check

    DOEpatents

    Destefan, Dennis E.; Stompro, David A.

    1991-01-01

    A preweld resistance check for resistance welding machines uses an open circuited measurement to determine the welding machine resistance, a closed circuit measurement to determine the parallel resistance of a workpiece set and the machine, and a calculation to determine the resistance of the workpiece set. Any variation in workpiece set or machine resistance is an indication that the weld may be different from a control weld.

  3. Multilevel Resistance Programming in Conductive Bridge Resistive Memory

    NASA Astrophysics Data System (ADS)

    Mahalanabis, Debayan

    -configurable resistive weights is also discussed. Lastly, Spike timing dependent plasticity (STDP) based gradual resistance change behavior in CBRAM device fabricated in back-end-of-line on a CMOS die containing integrate and fire CMOS neuron circuits is demonstrated for the first time which indicates the feasibility of using CBRAM devices as electronic synapses in spiking neural network hardware implementations for non-Boolean neuromorphic computing.

  4. "Halal-ing" the Child: Reframing Identities of Resistance in an Urban Muslim School

    ERIC Educational Resources Information Center

    Nasir, Na'ilah Suad

    2004-01-01

    In this article, Na'ilah Suad Nasir expands the literature on resistance theory by exploring the institutional response to classic "resistant" or "oppositional" student behavior. Using the case of one boy in an urban Muslim school who displays these resistant behaviors, she shows how the ideational artifacts of family and spirituality are enacted…

  5. "Halal-ing" the Child: Reframing Identities of Resistance in an Urban Muslim School

    ERIC Educational Resources Information Center

    Nasir, Na'ilah Suad

    2004-01-01

    In this article, Na'ilah Suad Nasir expands the literature on resistance theory by exploring the institutional response to classic "resistant" or "oppositional" student behavior. Using the case of one boy in an urban Muslim school who displays these resistant behaviors, she shows how the ideational artifacts of family and spirituality are enacted…

  6. Resistant hypertension.

    PubMed

    Armario, P; Oliveras, A; de la Sierra, A

    2013-11-01

    A 53 year old woman with hypercholesterolemia treated with statins, with no history of cardiovascular disease, was referred to the Hypertension and Vascular Risk Unit for management of hypertension resistant to 4 antihypertensive agents at full doses. The patient had obesity, with a body mass index of 36.3kg/m(2) and office blood pressure 162/102mm Hg. Physical examination showed no data of interest. glucose 120mg/dl, glycated Hb: 6.4%, albuminuria 68mg/g, kidney function and study of the renin angiotensin system and other biochemical parameters were normal. Echocardiography: left ventricular mass, 131g/m(2) (normal, <110g/m(2)). True resistant hypertension was confirmed by ambulatory monitoring of blood pressure during 24h (153/89mm Hg). Spironolactone treatment (25mg/day) was added and was well tolerated, with no change in renal function and kaliemia within normal (4.1mmol/l) following the treatment. After 8 weeks, blood pressure was well controlled: office blood pressure 132/86mm Hg and 24h-ambulatory blood pressure: 128/79mm Hg. Copyright © 2013 Elsevier España, S.L. All rights reserved.

  7. Toward an integrative perspective on resistance to change.

    PubMed

    Arkowitz, Hal

    2002-02-01

    This article presents an integrative perspective on resistance. The phenomena of resistance can be seen at the behavioral, interpersonal, cognitive, and affective levels. A set of integrative working assumptions is proposed in which resistance reflects meaningful information about clients' conflicts among various aspects of their selves relating to change. In this view, resistance is determined by intrapersonal and interpersonal factors and can occur with or without conscious awareness. Integrative approaches to working with these conflicts are described. Copyright 2002 John Wiley & Sons, Inc.

  8. Behavior Therapy

    MedlinePlus

    ... Email Print Share Behavior Therapy for Children with ADHD Page Content Most experts recommend using both medication and behavior therapy to treat ADHD. This is known as a multimodal treatment approach . ...

  9. Behavioral Coaching

    PubMed Central

    Seniuk, Holly A.; Witts, Benjamin N.; Williams, W. Larry.; Ghezzi, Patrick M.

    2013-01-01

    The term behavioral coaching has been used inconsistently in and outside the field of behavior analysis. In the sports literature, the term has been used to describe various intervention strategies, and in the organizational behavior management literature it has been used to describe an approach to training management personnel and staff. This inconsistency is problematic in terms of the replication of behavioral coaching across studies and aligning with Baer, Wolf, and Risley's (1968) technological dimension of applied behavior analysis. The current paper will outline and critique the discrepancies in the use of the term and suggest how Martin and Hrycaiko's (1983) characteristics of behavioral coaching in sports may be used to bring us closer to establishing a consistent definition of the term. In addition, we will suggest how these characteristics can also be applicable to the use of the term behavioral coaching in other domains of behavior analysis. PMID:25729141

  10. Behavioral coaching.

    PubMed

    Seniuk, Holly A; Witts, Benjamin N; Williams, W Larry; Ghezzi, Patrick M

    2013-01-01

    The term behavioral coaching has been used inconsistently in and outside the field of behavior analysis. In the sports literature, the term has been used to describe various intervention strategies, and in the organizational behavior management literature it has been used to describe an approach to training management personnel and staff. This inconsistency is problematic in terms of the replication of behavioral coaching across studies and aligning with Baer, Wolf, and Risley's (1968) technological dimension of applied behavior analysis. The current paper will outline and critique the discrepancies in the use of the term and suggest how Martin and Hrycaiko's (1983) characteristics of behavioral coaching in sports may be used to bring us closer to establishing a consistent definition of the term. In addition, we will suggest how these characteristics can also be applicable to the use of the term behavioral coaching in other domains of behavior analysis.

  11. Behavioral Economics

    PubMed Central

    Reed, Derek D.; Niileksela, Christopher R.; Kaplan, Brent A.

    2013-01-01

    In recent years, behavioral economics has gained much attention in psychology and public policy. Despite increased interest and continued basic experimental studies, the application of behavioral economics to therapeutic settings remains relatively sparse. Using examples from both basic and applied studies, we provide an overview of the principles comprising behavioral economic perspectives and discuss implications for behavior analysts in practice. A call for further translational research is provided. PMID:25729506

  12. Verbal behavior.

    PubMed

    Michael, J

    1984-11-01

    THE RECENT HISTORY AND CURRENT STATUS OF THE AREA OF VERBAL BEHAVIOR ARE CONSIDERED IN TERMS OF THREE MAJOR THEMATIC LINES: the operant conditioning of adult verbal behavior, learning to be an effective speaker and listener, and developments directly related to Skinner's Verbal Behavior. Other topics not directly related to the main themes are also considered: the work of Kurt Salzinger, ape-language research, and human operant research related to rule-governed behavior.

  13. The analysis of behavioral momentum

    PubMed Central

    Nevin, John A.; Mandell, Charlotte; Atak, Jean R.

    1983-01-01

    Learned behavior varies in its resistance to change, depending on the rate of reinforcement. Resistance to change may be characterized as behavioral momentum, which in turn may be analyzed into terms corresponding to mass and velocity in classical physics. Behavioral mass may be inferred from changes in response rate when experimental conditions are altered. Relevant data were obtained by training pigeons to peck a key on two-component multiple variable-interval, variable-interval schedules. Six pigeons were studied on three pairs of variable-interval schedules in all possible orders. When performance stabilized, resistance to change was assessed by arranging response-independent food during periods between components and by extinction. For each operation, the data for all schedule performances converged onto a single function, permitting estimation of the ratio of behavioral masses for each pair of schedules. The response-independent food data suggested that the ratio of behavioral masses is a power function of the ratio of reinforcement rates and that behavioral mass may be measured on a ratio scale. PMID:16812312

  14. Extinction, relapse, and behavioral momentum.

    PubMed

    Podlesnik, Christopher A; Shahan, Timothy A

    2010-05-01

    Previous experiments on behavioral momentum have shown that relative resistance to extinction of operant behavior in the presence of a discriminative stimulus depends upon the baseline rate or magnitude of reinforcement associated with that stimulus (i.e., the Pavlovian stimulus-reinforcer relation). Recently, we have shown that relapse of operant behavior in reinstatement, resurgence, and context renewal preparations also is a function of baseline stimulus-reinforcer relations. In this paper we present new data examining the role of baseline stimulus-reinforcer relations on resistance to extinction and relapse using a variety of baseline training conditions and relapse operations. Furthermore, we evaluate the adequacy of a behavioral momentum based model in accounting for the results. The model suggests that relapse occurs as a result of a decrease in the disruptive impact of extinction precipitated by a change in circumstances associated with extinction, and that the degree of relapse is a function of the pre-extinction baseline Pavlovian stimulus-reinforcer relation. Across experiments, relative resistance to extinction and relapse were greater in the presence of stimuli associated with more favorable conditions of reinforcement and were positively related to one another. In addition, the model did a good job in accounting for these effects. Thus, behavioral momentum theory may provide a useful quantitative approach for characterizing how differential reinforcement conditions contribute to relapse of operant behavior.

  15. Extinction, Relapse, and Behavioral Momentum

    PubMed Central

    Podlesnik, Christopher A.; Shahan, Timothy A.

    2010-01-01

    Previous experiments on behavioral momentum have shown that relative resistance to extinction of operant behavior in the presence of a discriminative stimulus depends upon the baseline rate or magnitude of reinforcement associated with that stimulus (i.e., the Pavlovian stimulus-reinforcer relation). Recently, we have shown that relapse of operant behavior in reinstatement, resurgence, and context renewal preparations also is a function of baseline stimulus-reinforcer relations. In this paper we present new data examining the role of baseline stimulus-reinforcer relations on resistance to extinction and relapse using a variety of baseline training conditions and relapse operations. Furthermore, we evaluate the adequacy of a behavioral-momentum based model in accounting for the results. The model suggests that relapse occurs as a result of a decrease in the disruptive impact of extinction precipitated by a change in circumstances associated with extinction, and that the degree of relapse is a function of the pre-extinction baseline Pavlovian stimulus-reinforcer relation. Across experiments, relative resistance to extinction and relapse were greater in the presence of stimuli associated with more favorable conditions of reinforcement and were positively related to one another. In addition, the model did a good job in accounting for these effects. Thus, behavioral momentum theory may provide a useful quantitative approach for characterizing how differential reinforcement conditions contribute to relapse of operant behavior. PMID:20152889

  16. Pulmonary surfactant: phase behavior and function.

    PubMed

    Piknova, Barbora; Schram, Vincent; Hall, Stephen B

    2002-08-01

    Pulmonary surfactant functions by first flowing rapidly into the alveolar air/water interface, but then resisting collapse from the surface when the adsorbed interfacial film is compressed during exhalation. Widely accepted models emphasize the importance of phase behavior in both processes. Recent studies show, however, that fluidity is a relatively minor determinant of adsorption and that solid films, which resist collapse, can form by kinetic processes unrelated to equilibrium phase behavior.

  17. Behaviorally Speaking.

    ERIC Educational Resources Information Center

    Porter, Elias H.; Dutton, Darell W. J.

    1987-01-01

    Consists of two articles focusing on (1) a modern behavioral model that takes cues from Hippocrates' Four Temperaments and (2) use of a behavioral approach to improve the effectiveness of meetings. Lists positive and negative behaviors within the meeting context. (CH)

  18. Behavioral Medicine.

    ERIC Educational Resources Information Center

    Garfield, Sol L., Ed.

    1982-01-01

    Contains 18 articles discussing the uses of behavioral medicine in such areas as obesity, smoking, hypertension, and headache. Reviews include discussions of behavioral medicine and insomnia, chronic pain, asthma, peripheral vascular disease, and coronary-prone behavior. Newly emerging topics include gastrointestinal disorders, arthritis,…

  19. Behaviorally Speaking.

    ERIC Educational Resources Information Center

    Porter, Elias H.; Dutton, Darell W. J.

    1987-01-01

    Consists of two articles focusing on (1) a modern behavioral model that takes cues from Hippocrates' Four Temperaments and (2) use of a behavioral approach to improve the effectiveness of meetings. Lists positive and negative behaviors within the meeting context. (CH)

  20. Behavioral Medicine.

    ERIC Educational Resources Information Center

    Garfield, Sol L., Ed.

    1982-01-01

    Contains 18 articles discussing the uses of behavioral medicine in such areas as obesity, smoking, hypertension, and headache. Reviews include discussions of behavioral medicine and insomnia, chronic pain, asthma, peripheral vascular disease, and coronary-prone behavior. Newly emerging topics include gastrointestinal disorders, arthritis,…

  1. Making Behavioral Activation More Behavioral

    ERIC Educational Resources Information Center

    Kanter, Jonathan W.; Manos, Rachel C.; Busch, Andrew M.; Rusch, Laura C.

    2008-01-01

    Behavioral Activation, an efficacious treatment for depression, presents a behavioral theory of depression--emphasizing the need for clients to contact positive reinforcement--and a set of therapeutic techniques--emphasizing provision of instructions rather than therapeutic provision of reinforcement. An integration of Behavioral Activation with…

  2. Making Behavioral Activation More Behavioral

    ERIC Educational Resources Information Center

    Kanter, Jonathan W.; Manos, Rachel C.; Busch, Andrew M.; Rusch, Laura C.

    2008-01-01

    Behavioral Activation, an efficacious treatment for depression, presents a behavioral theory of depression--emphasizing the need for clients to contact positive reinforcement--and a set of therapeutic techniques--emphasizing provision of instructions rather than therapeutic provision of reinforcement. An integration of Behavioral Activation with…

  3. Coping with Student Resistance to Critical Thinking: What the Psychotherapy Literature Can Tell Us.

    ERIC Educational Resources Information Center

    Keeley, Stuart M.; And Others

    1995-01-01

    Techniques for college teachers to use in managing student resistance to critical thinking include proactive strategies (creating a cooperative environment, establishing rapport, creating high expectations, and countering resistive behavior) and reactive strategies (avoiding personalization of resistance, inviting students to explore resistance,…

  4. Coping with Student Resistance to Critical Thinking: What the Psychotherapy Literature Can Tell Us.

    ERIC Educational Resources Information Center

    Keeley, Stuart M.; And Others

    1995-01-01

    Techniques for college teachers to use in managing student resistance to critical thinking include proactive strategies (creating a cooperative environment, establishing rapport, creating high expectations, and countering resistive behavior) and reactive strategies (avoiding personalization of resistance, inviting students to explore resistance,…

  5. Psychological behaviorism and behaviorizing psychology

    PubMed Central

    Staats, Arthur W.

    1994-01-01

    Paradigmatic or psychological behaviorism (PB), in a four-decade history of development, has been shaped by its goal, the establishment of a behaviorism that can also serve as the approach in psychology (Watson's original goal). In the process, PB has become a new generation of behaviorism with abundant heuristic avenues for development in theory, philosophy, methodology, and research. Psychology has resources, purview and problem areas, and nascent developments of many kinds, gathered in chaotic diversity, needing unification (and other things) that cognitivism cannot provide. Behaviorism can, within PB's multilevel framework for connecting and advancing both psychology and behaviorism. PMID:22478175

  6. Psychological behaviorism and behaviorizing psychology.

    PubMed

    Staats, A W

    1994-01-01

    Paradigmatic or psychological behaviorism (PB), in a four-decade history of development, has been shaped by its goal, the establishment of a behaviorism that can also serve as the approach in psychology (Watson's original goal). In the process, PB has become a new generation of behaviorism with abundant heuristic avenues for development in theory, philosophy, methodology, and research. Psychology has resources, purview and problem areas, and nascent developments of many kinds, gathered in chaotic diversity, needing unification (and other things) that cognitivism cannot provide. Behaviorism can, within PB's multilevel framework for connecting and advancing both psychology and behaviorism.

  7. Mechanisms of drug resistance: quinolone resistance

    PubMed Central

    Hooper, David C.; Jacoby, George A.

    2015-01-01

    Quinolone antimicrobials are synthetic and widely used in clinical medicine. Resistance emerged with clinical use and became common in some bacterial pathogens. Mechanisms of resistance include two categories of mutation and acquisition of resistance-conferring genes. Resistance mutations in one or both of the two drug target enzymes, DNA gyrase and DNA topoisomerase IV, are commonly in a localized domain of the GyrA and ParE subunits of the respective enzymes and reduce drug binding to the enzyme-DNA complex. Other resistance mutations occur in regulatory genes that control the expression of native efflux pumps localized in the bacterial membrane(s). These pumps have broad substrate profiles that include quinolones as well as other antimicrobials, disinfectants, and dyes. Mutations of both types can accumulate with selection pressure and produce highly resistant strains. Resistance genes acquired on plasmids can confer low-level resistance that promotes the selection of mutational high-level resistance. Plasmid-encoded resistance is due to Qnr proteins that protect the target enzymes from quinolone action, one mutant aminoglycoside-modifying enzyme that also modifies certain quinolones, and mobile efflux pumps. Plasmids with these mechanisms often encode additional antimicrobial resistances and can transfer multidrug resistance that includes quinolones. Thus, the bacterial quinolone resistance armamentarium is large. PMID:26190223

  8. Mechanisms of drug resistance: quinolone resistance.

    PubMed

    Hooper, David C; Jacoby, George A

    2015-09-01

    Quinolone antimicrobials are synthetic and widely used in clinical medicine. Resistance emerged with clinical use and became common in some bacterial pathogens. Mechanisms of resistance include two categories of mutation and acquisition of resistance-conferring genes. Resistance mutations in one or both of the two drug target enzymes, DNA gyrase and DNA topoisomerase IV, are commonly in a localized domain of the GyrA and ParE subunits of the respective enzymes and reduce drug binding to the enzyme-DNA complex. Other resistance mutations occur in regulatory genes that control the expression of native efflux pumps localized in the bacterial membrane(s). These pumps have broad substrate profiles that include quinolones as well as other antimicrobials, disinfectants, and dyes. Mutations of both types can accumulate with selection pressure and produce highly resistant strains. Resistance genes acquired on plasmids can confer low-level resistance that promotes the selection of mutational high-level resistance. Plasmid-encoded resistance is due to Qnr proteins that protect the target enzymes from quinolone action, one mutant aminoglycoside-modifying enzyme that also modifies certain quinolones, and mobile efflux pumps. Plasmids with these mechanisms often encode additional antimicrobial resistances and can transfer multidrug resistance that includes quinolones. Thus, the bacterial quinolone resistance armamentarium is large.

  9. Teleological behaviorism.

    PubMed

    Rachlin, H

    1992-11-01

    A psychological science of efficient causes, using internal mechanisms to explain overt behavior, is distinguished from another psychological science, based on Aristotelian final causes, using external objects and goals to explain overt behavior. Efficient-cause psychology is designed to answer the question of how a particular act is emitted; final-cause psychology is designed to answer the question of why a particular act is emitted. Physiological psychology, modern cognitive psychology, and some parts of behaviorism including Skinnerian behaviorism are efficient-cause psychologies; final-cause psychology, a development of Skinnerian behaviorism, is here called teleological behaviorism. Each of these two conceptions of causality in psychology implies a different view of the mind, hence a different meaning of mental terms.

  10. Behavioral Momentum Theory: Equations and Applications

    ERIC Educational Resources Information Center

    Nevin, John A.; Shahan, Timothy A.

    2011-01-01

    Behavioral momentum theory provides a quantitative account of how reinforcers experienced within a discriminative stimulus context govern the persistence of behavior that occurs in that context. The theory suggests that all reinforcers obtained in the presence of a discriminative stimulus increase resistance to change, regardless of whether those…

  11. EFFECTS OF ELECTRODE RESISTANCE ON THE DIELECTRIC BEHAVIORS OF Au/BaxSr1-xTiO3/La1.1Sr0.9NiO4 CAPACITORS

    NASA Astrophysics Data System (ADS)

    Qiu, Jie; Liu, Guozhen; Wolfman, Jérôme

    2016-05-01

    BaxSr1-xTiO3 (0.1≤x≤0.5) (BST) thin films were prepared on La1.1Sr0.9NiO4 (LSNO)/SrTiO3 (STO) structure by combinatorial pulsed laser deposition (comb-PLD). The capacitances of the Au/BST/LSNO capacitors exhibited strong frequency dependence especially when the applied frequency was higher than 10kHz. On the basis of an equivalent circuit model, we presented a theoretical simulation of the relationships between capacitance and frequency for the capacitors with different electrode serial resistances. Based on the fitting results, the observed strong frequency dependence of the measured capacitance at high frequency in our study could be ascribed to the large serial resistance of 750 Ω for oxide electrode LSNO. Further simulation studies found that large serial resistance (1000 Ω) could result in an apparent deviation from the intrinsic dielectric properties especially at high frequencies (>100kHz) for capacitors with capacitances above 1nF. Our results provide useful information for the design of all-oxide electronic devices.

  12. Behavior modification.

    PubMed

    Pelham, W E; Fabiano, G A

    2000-07-01

    Attention deficit/hyperactivity disorder (ADHD) is a chronic and substantially impairing disorder. This means that treatment must also be chronic and substantial. Behavior Modification, and in many cases, the combination of behavior modification and stimulant medication, is a valid, useful treatment for reducing the pervasive impairment experienced by children with ADHD. Based on the research evidence reviewed, behavior modification should be the first line of treatment for children with ADHD.

  13. Wrestling with Resistance.

    ERIC Educational Resources Information Center

    Hartzell, Gary

    1996-01-01

    Discusses reasons for and methods to defuse classroom teachers' resistance to change in the workplace. Suggestions include planning for resistance, acknowledging peoples' concerns and addressing them specifically, avoiding criticism of current methods, individualizing resistance reduction, and providing ongoing support. (JKP)

  14. Combating Antibiotic Resistance

    MedlinePlus

    ... For Consumers Home For Consumers Consumer Updates Combating Antibiotic Resistance Share Tweet Linkedin Pin it More sharing options ... however, have contributed to a phenomenon known as antibiotic resistance. This resistance develops when potentially harmful bacteria change ...

  15. Behavioral toxicology

    SciTech Connect

    Needleman, H.L.

    1995-09-01

    The new fields of behavioral toxicology and behavioral teratology investigate the outcome of specific toxic exposures in humans and animals on learning, memory, and behavioral characteristics. Three important classes of behavioral neurotoxicants are metals, solvents, and pesticides. The clearest data on the deleterious effects of prenatal exposure to toxicants comes from the study of two metals, lead and mercury, and form epidemiological investigations of the effects of alcohol taken during pregnancy. Less complete data are available for two other groups of agents, solvents, and pesticides. What we do know about their effects on the fetal brain is convincing enough to make us demand caution in their distribution. 15 refs.

  16. A gestalt-experiential perspective on resistance.

    PubMed

    Engle, David; Holiman, Marjorie

    2002-02-01

    The authors present background on the gestalt-experiential understanding of resistance, conceptualized to be either resistance to awareness or resistance to contact. The authors discuss why they do not use the term resistance and describe the phenomena as a client's self-protective attempt to avoid the anxiety necessitated by change. Such resistant behaviors occur outside a client's awareness and often result in an ambivalence or conflict about change. The authors also describe using in-session experiments as a way to engage with the client in exploring such a state of ambivalence or conflict. Finally, they respond to the case studies presented elsewhere in this issue and propose intervention strategies consistent with the gestalt-experiential perspective. Copyright 2002 John Wiley & Sons, Inc.

  17. Behavior Matters

    PubMed Central

    Fisher, Edwin B.; Fitzgibbon, Marian L.; Glasgow, Russell E.; Haire-Joshu, Debra; Hayman, Laura L.; Kaplan, Robert M.; Nanney, Marilyn S.; Ockene, Judith K.

    2011-01-01

    Behavior has a broad and central role in health. Behavioral interventions can be effectively used to prevent disease, improve management of existing disease, increase quality of life, and reduce healthcare costs. A summary is presented of evidence for these conclusions in cardiovascular disease/diabetes, cancer, and HIV/AIDS as well as with key risk factors: tobacco use, poor diet, physical inactivity, and excessive alcohol consumption. For each, documentation is made of (1) moderation of genetic and other fundamental biological influences by behaviors and social–environmental factors, (2) impacts of behaviors on health, (3) success of behavioral interventions in prevention, (4) disease management, (5) and quality of life, and (6) improvements in the health of populations through behavioral health promotion programs. Evidence indicates the cost effectiveness and value of behavioral interventions, especially relative to other common health services, as well as the value they add in terms of quality of life. Pertinent to clinicians and their patients as well as to health policy and population health, the benefits of behavioral interventions extend beyond impacts on a particular disease or risk factor. Rather, they include broad effects and benefits on prevention, disease management, and well-being across the life span. Among priorities for dissemination research, the application of behavioral approaches is challenged by diverse barriers, including socioeconomic barriers linked to health disparities. However, behavioral approaches including those emphasizing community and social influences appear to be useful in addressing such challenges. In sum, behavioral approaches should have a central place in prevention and health care of the 21st century. PMID:21496745

  18. Exercise, Stress Resistance, and Central Serotonergic Systems

    PubMed Central

    Greenwood, Benjamin N.; Fleshner, Monika

    2015-01-01

    Voluntary exercise reduces the incidence of stress-related psychiatric disorders in humans and prevents serotonin-dependent behavioral consequences of stress in rodents. Evidence reviewed herein is consistent with the hypothesis that exercise increases stress resistance by producing neuroplasticity at multiple sites of the central serotonergic system, which all help to limit the behavioral impact of acute increases in serotonin during stressor exposure. PMID:21508844

  19. Behavioral economics.

    PubMed

    Camerer, Colin F

    2014-09-22

    Behavioral economics uses evidence from psychology and other social sciences to create a precise and fruitful alternative to traditional economic theories, which are based on optimization. Behavioral economics may interest some biologists, as it shifts the basis for theories of economic choice away from logical calculation and maximization and toward biologically plausible mechanisms.

  20. Aggressive Behavior

    MedlinePlus

    ... Listen Español Text Size Email Print Share Aggressive Behavior Page Content Article Body My child is sometimes very aggressive. What is the best ... once they are quiet and still reinforces this behavior, so your child learns that time out means “quiet and still.” ...

  1. Making behavioral activation more behavioral.

    PubMed

    Kanter, Jonathan W; Manos, Rachel C; Busch, Andrew M; Rusch, Laura C

    2008-11-01

    Behavioral Activation, an efficacious treatment for depression, presents a behavioral theory of depression--emphasizing the need for clients to contact positive reinforcement--and a set of therapeutic techniques--emphasizing provision of instructions rather than therapeutic provision of reinforcement. An integration of Behavioral Activation with another behavioral treatment, Functional Analytic Psychotherapy, addresses this mismatch. Functional Analytic Psychotherapy provides a process for the therapeutic provision of immediate and natural reinforcement. This article presents this integration and offers theoretical and practical therapist guidelines on its application. Although the integration is largely theoretical, empirical data are presented in its support when available. The article ends with a discussion of future research directions.

  2. Antibiotic resistance in Chlamydiae.

    PubMed

    Sandoz, Kelsi M; Rockey, Daniel D

    2010-09-01

    There are few documented reports of antibiotic resistance in Chlamydia and no examples of natural and stable antibiotic resistance in strains collected from humans. While there are several reports of clinical isolates exhibiting resistance to antibiotics, these strains either lost their resistance phenotype in vitro, or lost viability altogether. Differences in procedures for chlamydial culture in the laboratory, low recovery rates of clinical isolates and the unknown significance of heterotypic resistance observed in culture may interfere with the recognition and interpretation of antibiotic resistance. Although antibiotic resistance has not emerged in chlamydiae pathogenic to humans, several lines of evidence suggest they are capable of expressing significant resistant phenotypes. The adept ability of chlamydiae to evolve to antibiotic resistance in vitro is demonstrated by contemporary examples of mutagenesis, recombination and genetic transformation. The isolation of tetracycline-resistant Chlamydia suis strains from pigs also emphasizes their adaptive ability to acquire antibiotic resistance genes when exposed to significant selective pressure.

  3. Investigation of Social Influence Theory's Conception of Client Resistance.

    ERIC Educational Resources Information Center

    Ruppel, George; Kaul, Theodore J.

    1982-01-01

    Investigated the predictions of social influence theory with respect to client resistance to counselor influence. Data offered support for the social influence theory in that subjects' expectations of others' instrumental behavior were lower for those who viewed illegitimate counselors. (Author)

  4. Uniform Self-rectifying Resistive Switching Behavior via Preformed Conducting Paths in a Vertical-type Ta2O5/HfO2-x Structure with a Sub-μm(2) Cell Area.

    PubMed

    Yoon, Jung Ho; Yoo, Sijung; Song, Seul Ji; Yoon, Kyung Jean; Kwon, Dae Eun; Kwon, Young Jae; Park, Tae Hyung; Kim, Hye Jin; Shao, Xing Long; Kim, Yumin; Hwang, Cheol Seong

    2016-07-20

    To replace or succeed the present NAND flash memory, resistive switching random access memory (ReRAM) should be implemented in the vertical-type crossbar array configuration. The ReRAM cell must have a highly reproducible resistive switching (RS) performance and an electroforming-free, self-rectifying, low-power-consumption, multilevel-switching, and easy fabrication process with a deep sub-μm(2) cell area. In this work, a Pt/Ta2O5/HfO2-x/TiN RS memory cell fabricated in the form of a vertical-type structure was presented as a feasible contender to meet the above requirements. While the fundamental RS characteristics of this material based on the electron trapping/detrapping mechanisms have been reported elsewhere, the influence of the cell scaling size to 0.34 μm(2) on the RS performance by adopting the vertical integration scheme was carefully examined in this work. The smaller cell area provided much better switching uniformity while all the other benefits of this specific material system were preserved. Using the overstressing technique, the nature of RS through the localized conducting path was further examined, which elucidated the fundamental difference between the present material system and the general ionic-motion-related bipolar RS mechanism.

  5. Tuning resistance states by thickness control in an electroforming-free nanometallic complementary resistance random access memory

    SciTech Connect

    Yang, Xiang; Lu, Yang; Lee, Jongho; Chen, I-Wei

    2016-01-04

    Tuning low resistance state is crucial for resistance random access memory (RRAM) that aims to achieve optimal read margin and design flexibility. By back-to-back stacking two nanometallic bipolar RRAMs with different thickness into a complementary structure, we have found that its low resistance can be reliably tuned over several orders of magnitude. Such high tunability originates from the exponential thickness dependence of the high resistance state of nanometallic RRAM, in which electron wave localization in a random network gives rise to the unique scaling behavior. The complementary nanometallic RRAM provides electroforming-free, multi-resistance-state, sub-100 ns switching capability with advantageous characteristics for memory arrays.

  6. Electrode-induced digital-to-analog resistive switching in TaO x -based RRAM devices.

    PubMed

    Li, Xinyi; Wu, Huaqiang; Bin Gao; Wu, Wei; Wu, Dong; Deng, Ning; Cai, Jian; Qian, He

    2016-07-29

    In RRAM devices, electrodes play a significant role during the switching process. In this paper, different top electrodes are used for TaO y /Ta2O5-x /AlO σ triple-oxide-layer devices. Top electrode-induced digital resistive switching to analog resistive switching was observed. For Pt top electrode (TE) devices, abrupt digital resistive switching behavior was observed, while Al TE devices showed gradual analog resistive switching behavior. Devices with various AlO σ thicknesses and sizes were fabricated and characterized to evaluate the reliability of the analog resistive switching. The physical mechanisms responsible for this electrode-induced resistive switching behavior were discussed.

  7. Behavioral epigenetics

    PubMed Central

    Lester, Barry M.; Tronick, Edward; Nestler, Eric; Abel, Ted; Kosofsky, Barry; Kuzawa, Christopher W.; Marsit, Carmen J.; Maze, Ian; Meaney, Michael J.; Monteggia, Lisa M.; Reul, Johannes M. H. M.; Skuse, David H.; Sweatt, J. David; Wood, Marcelo A.

    2013-01-01

    Sponsored by the New York Academy of Sciences, the Warren Alpert Medical School of Brown University and the University of Massachusetts Boston, “Behavioral Epigenetics” was held on October 29–30, 2010 at the University of Massachusetts Boston Campus Center, Boston, Massachusetts. This meeting featured speakers and panel discussions exploring the emerging field of behavioral epigenetics, from basic biochemical and cellular mechanisms to the epigenetic modulation of normative development, developmental disorders, and psychopathology. This report provides an overview of the research presented by leading scientists and lively discussion about the future of investigation at the behavioral epigenetic level. PMID:21615751

  8. Drug targeting of leptin resistance.

    PubMed

    Santoro, Anna; Mattace Raso, Giuseppina; Meli, Rosaria

    2015-11-01

    Leptin regulates glucose, lipid and energy homeostasis as well as feeding behavior, serving as a bridge between peripheral metabolically active tissues and the central nervous system (CNS). Indeed, this adipocyte-derived hormone, whose circulating levels mirror fat mass, not only exerts its anti-obesity effects mainly modulating the activity of specific hypothalamic neurons expressing the long form of the leptin receptor (Ob-Rb), but it also shows pleiotropic functions due to the activation of Ob-Rb in peripheral tissues. Nevertheless, several mechanisms have been suggested to mediate leptin resistance, including obesity-associated hyperleptinemia, impairment of leptin access to CNS and the reduction in Ob-Rb signal transduction effectiveness, among others. During the onset and progression of obesity, the dampening of leptin sensitivity often occurs, preventing the efficacy of leptin replacement therapy from overcoming obesity and/or its comorbidities. This review focuses on obesity-associated leptin resistance and the mechanisms underpinning this condition, to highlight the relevance of leptin sensitivity restoration as a useful therapeutic strategy to treat common obesity and its complications. Interestingly, although promising strategies to counteract leptin resistance have been proposed, these pharmacological approaches have shown limited efficacy or even relevant adverse effects in preclinical and clinical studies. Therefore, the numerous findings from this review clearly indicate a lack of a single and efficacious treatment for leptin resistance, highlighting the necessity to find new therapeutic tools to improve leptin sensitivity, especially in patients with most severe disease profiles.

  9. Heat-resistant anemometers for fire research

    Treesearch

    John R. Murray; Clive M. Countryman

    1968-01-01

    Heat-resistant anemometers have been developed for measuring horizontal and vertical air flow in fire behavior studies. The anemometers will continue to produce data as long as the anemometer body is less than 650°F. They can survive brief immersion in flame without major damage. These air-flow sensors have aluminum bodies and rotor hubs and stainless steel...

  10. Temporal Context, Preference, and Resistance to Change

    ERIC Educational Resources Information Center

    Podlesnik, Christopher A.; Jimenez-Gomez, Corina; Thrailkill, Eric A.; Shahan, Timothy A.

    2011-01-01

    According to behavioral momentum theory, preference and relative resistance to change in concurrent chains schedules are correlated and reflect the relative conditioned value of discriminative stimuli. In the present study, we explore the generality of this relation by manipulating the temporal context within a concurrent-chains procedure through…

  11. Rodent models of treatment-resistant depression

    PubMed Central

    Caldarone, Barbara J.; Zachariou, Venetia; King, Sarah L

    2015-01-01

    Major depression is a prevalent and debilitating disorder and a substantial proportion of patients fail to reach remission following standard antidepressant pharmacological treatment. Limited efficacy with currently available antidepressant drugs highlights the need to develop more effective medications for treatment resistant patients and emphasizes the importance of developing better preclinical models that focus on treatment resistant populations. This review discusses methods to adapt and refine rodent behavioral models that are predictive of antidepressant efficacy to identify populations that show reduced responsiveness or are resistant to traditional antidepressants. Methods include separating antidepressant responders from non-responders, administering treatments that render animals resistant to traditional pharmacological treatments, and identifying genetic models that show antidepressant resistance. This review also examines pharmacological and non-pharmacological treatments regimes that have been effective in refractory patients and how some of these approaches have been used to validate animal models of treatment-resistant depression. The goals in developing rodent models of treatment-resistant depression are to understand the neurobiological mechanisms involved in antidepressant resistance and to develop valid models to test novel therapies that would be effective in patients that do not respond to traditional monoaminergic antidepressants. PMID:25460020

  12. Behavior change

    USDA-ARS?s Scientific Manuscript database

    This brief entry presents the mediating-moderating variable model as a conceptual framework for understanding behavior change in regard to physical activity/exercise and adiposity. The ideas are applied to real world situations....

  13. Resisting Resistance: Targeted Therapies in Lung Cancer

    PubMed Central

    Lin, Jessica J.; Shaw, Alice T.

    2016-01-01

    Drug resistance inevitably limits the efficacy of all targeted therapies including tyrosine kinase inhibitors (TKIs). Understanding the biological underpinnings of TKI resistance is key to the successful development of future therapeutic strategies. Traditionally, mechanisms of TKI resistance have been viewed under a dichotomous lens. Tumor cells are TKI-sensitive or TKI-refractory, exhibit intrinsic or acquired resistance, and accumulate alterations within or outside the target to promote their survival. Such classifications facilitate our comprehension of an otherwise complex biology, but are likely an oversimplification. Recent studies underscore the multifaceted, genetically heterogeneous nature of TKI resistance, which evolves dynamically with changes in therapy. In this Review, we provide a broad framework for understanding the diverse mechanisms of resistance at play in oncogene-driven lung cancers. PMID:27819059

  14. Make Me! Understanding and Engaging Student Resistance in School

    ERIC Educational Resources Information Center

    Toshalis, Eric

    2015-01-01

    In this groundbreaking book, Eric Toshalis explores student resistance through a variety of perspectives, arguing that oppositional behaviors can be not only instructive but productive. All too often treated as a matter of compliance, student resistance can also be understood as a form of engagement, as young people confront and negotiate new…

  15. Changing Resistant Consultees: Functional Assessment Leading to Strategic Intervention

    ERIC Educational Resources Information Center

    Knoff, Howard M.

    2013-01-01

    Some consultees resist implementing, or implementing with integrity, effective academic or behavioral interventions that their consultants believe are needed to resolve specific student problems. In order to address consultee resistance, it is recommended that consultants complete functional assessments to determine the underlying reasons for the…

  16. Changing Resistant Consultees: Functional Assessment Leading to Strategic Intervention

    ERIC Educational Resources Information Center

    Knoff, Howard M.

    2013-01-01

    Some consultees resist implementing, or implementing with integrity, effective academic or behavioral interventions that their consultants believe are needed to resolve specific student problems. In order to address consultee resistance, it is recommended that consultants complete functional assessments to determine the underlying reasons for the…

  17. The Idea of Resistance in Education: A Critique.

    ERIC Educational Resources Information Center

    Reeves, Joyce King

    This paper discusses resistance in education as expressed in white working-class girls' reactions to sex role socialization, children's play, minority children's behavior in inner city schools, and the resistance of female faculty in institutions of higher education. The paper takes off from issues addressed in some papers presented at a research…

  18. New resistivity for high-mobility quantum Hall conductors

    NASA Technical Reports Server (NTRS)

    Mceuen, P. L.; Szafer, A.; Richter, C. A.; Alphenaar, B. W.; Jain, J. K.

    1990-01-01

    Measurements showing dramatic nonlocal behavior in the four-terminal resistances of a high-mobility quantum Hall conductor are presented. These measurements illustrate that the standard definition of the resistivity tensor is inappropriate, but they are in excellent agreement with a new model of the conductor that treats the edge and bulk conducting pathways independently. This model uses a single intensive parameter, analogous to a local resistivity for the bulk channel only, to characterize the system.

  19. Metallic behavior and negative differential resistance properties of (InAs)n (n = 2 - 4) molecule cluster junctions via a combined non-equilibrium Green's function and density functional theory study

    NASA Astrophysics Data System (ADS)

    Wang, Qi; Zhang, Jianbing; Li, Rong; Xu, Yuanlan; Miao, Xiangshui; Zhang, Daoli

    2014-06-01

    In this present work, the geometric structures and electronic transport properties of (InAs)n (n = 2, 3, 4) molecule cluster junctions are comparatively investigated using NEGF combined with DFT. Results indicate that all (InAs)n molecule cluster junctions present metallic behavior at the low applied biases ([-2V, 2V]), while NDR appears at a certain high bias range. Our calculation shows that the current of (InAs)4 molecule cluster-based junction is almost the largest at any bias. The mechanisms of the current-voltage characteristics of all the three molecule cluster junctions are proposed.

  20. Metallic behavior and negative differential resistance properties of (InAs){sub n} (n = 2 − 4) molecule cluster junctions via a combined non–equilibrium Green's function and density functional theory study

    SciTech Connect

    Wang, Qi; Li, Rong; Xu, Yuanlan; Zhang, Jianbing; Miao, Xiangshui; Zhang, Daoli

    2014-06-21

    In this present work, the geometric structures and electronic transport properties of (InAs){sub n} (n = 2, 3, 4) molecule cluster junctions are comparatively investigated using NEGF combined with DFT. Results indicate that all (InAs){sub n} molecule cluster junctions present metallic behavior at the low applied biases ([−2V, 2V]), while NDR appears at a certain high bias range. Our calculation shows that the current of (InAs){sub 4} molecule cluster–based junction is almost the largest at any bias. The mechanisms of the current–voltage characteristics of all the three molecule cluster junctions are proposed.

  1. Anthelmintic resistance: markers for resistance, or susceptibility?

    PubMed Central

    BEECH, R. N.; SKUCE, P.; BARTLEY, D. J.; MARTIN, R. J.; PRICHARD, R. K.; GILLEARD, J. S.

    2010-01-01

    SUMMARY The Consortium for Anthelmintic Resistance and Susceptibility (CARS) brings together researchers worldwide, with a focus of advancing knowledge of resistance and providing information on detection methods and treatment strategies. Advances in this field suggest mechanisms and features of resistance that are shared among different classes of anthelmintic. Benzimidazole resistance is characterized by specific amino acid substitutions in beta-tubulin. If present, these substitutions increase in frequency upon drug treatment and lead to treatment failure. In the laboratory, sequence substitutions in ion-channels can contribute to macrocyclic lactone resistance, but there is little evidence that they are significant in the field. Changes in gene expression are associated with resistance to several different classes of anthelmintic. Increased P-glycoprotein expression may prevent drug access to its site of action. Decreased expression of ion-channel subunits and the loss of specific receptors may remove the drug target. Tools for the identification and genetic analysis of parasitic nematodes and a new online database will help to coordinate research efforts in this area. Resistance may result from a loss of sensitivity as well as the appearance of resistance. A focus on the presence of anthelmintic susceptibility may be as important as the detection of resistance. PMID:20825689

  2. Methicillin-resistant staphylococci.

    PubMed Central

    Chambers, H F

    1988-01-01

    Strains of staphylococci resistant to methicillin were identified immediately after introduction of this drug. Methicillin-resistant strains have unusual properties, the most notable of which is extreme variability in expression of the resistance trait. The conditions associated with this heterogeneous expression of resistance are described. Methicillin resistance is associated with production of a unique penicillin-binding protein (PBP), 2a, which is bound and inactivated only at high concentrations of beta-lactam antibiotics. PBP2a appears to be encoded by the mec determinant, which also is unique to methicillin-resistant strains. The relationships between PBP2a and expression of resistance and implications for the mechanism of resistance are discussed. The heterogeneous expression of methicillin resistance by staphylococci poses problems in the detection of resistant strains. Experience with several susceptibility test methods is reviewed and guidelines for performance of these tests are given. Treatment of infections caused by methicillin-resistant staphylococci is discussed. Vancomycin is the treatment of choice. Alternatives have been few because methicillin-resistant strains often are resistant to multiple antibiotics in addition to beta-lactam antibiotics. New agents which are active against methicillin-resistant staphylococci are becoming available, and their potential role in treatment is discussed. Images PMID:3069195

  3. Scratch behaviors in polymers

    NASA Astrophysics Data System (ADS)

    Xiang, Chen

    2000-10-01

    As part of a large effort toward the fundamental understanding of scratch behaviors in polymeric materials, studies were carried out on a broad range of polymers, with an emphasis on automotive thermoplastic olefins (TPOs). Two types of scratch tests were performed in this research, i.e., Ford constant load and instrumented progressive load scratch tests. A scratch model proposed by Hamilton and Goodman was applied to understand the fundamental mechanics of the scratch process. Several characterization techniques were used to investigate the scratch damage mechanisms in polymers. Both testing results and the scratch model analysis indicate that certain rigidity in polymers is essential to give good scratch resistance. Fundamental understanding of the scratching process in terms of basic material characteristics such as Young's modulus, yield stress, tensile strength, friction coefficient, scratch hardness, penetration recovery and fracture toughness are discussed. Scratch damage investigation, on both surface and subsurface, shows that shear yielding is the main cause of the plastics flow scratch pattern, while tensile tear on the surface and shear induced fracture on the subsurface are the main damage mechanisms in the fracture scratch pattern. This study explains why automotive TPOs are susceptible to scratch under the current scratch test practiced in automotive industry. Shear deformation and fracture behavior in model TPOs are also studied using the Iosipescu shear test. Iosipescu shear deformation in terms of shear stress-strain curves of model TPOs is obtained experimentally. Shear fracture process and damage mechanisms in TPOs are also demonstrated and revealed. Further studies on the scratch damage in TPOs based on the roles of additives and fillers in the scratch behavior are addressed. The effects of phase morphology and toughening mechanisms on scratch behavior in TPOs are also discussed. This research has resulted in an increased understanding of the

  4. Evolutionary consequences of behavioral diversity

    PubMed Central

    Parsons, Todd L.; Plotkin, Joshua B.

    2016-01-01

    Iterated games provide a framework to describe social interactions among groups of individuals. This body of work has focused primarily on individuals who face a simple binary choice, such as “cooperate” or “defect.” Real individuals, however, can exhibit behavioral diversity, varying their input to a social interaction both qualitatively and quantitatively. Here we explore how access to a greater diversity of behavioral choices impacts the evolution of social dynamics in populations. We show that, in public goods games, some simple strategies that choose between only two possible actions can resist invasion by all multichoice invaders, even while engaging in relatively little punishment. More generally, access to a larger repertoire of behavioral choices results in a more ”rugged” fitness landscape, with populations able to stabilize cooperation at multiple levels of investment. As a result, increased behavioral choice facilitates cooperation when returns on investments are low, but it hinders cooperation when returns on investments are high. Finally, we analyze iterated rock–paper–scissors games, the nontransitive payoff structure of which means that unilateral control is difficult to achieve. Despite this, we find that a large proportion of multichoice strategies can invade and resist invasion by single-choice strategies—so that even well-mixed populations will tend to evolve and maintain behavioral diversity. PMID:27791109

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

    PubMed

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

    2006-09-01

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

  6. A mathematical model of leptin resistance.

    PubMed

    Jacquier, Marine; Soula, Hédi A; Crauste, Fabien

    2015-09-01

    Obesity is often associated with leptin resistance, which leads to a physiological system with high leptin concentration but unable to respond to leptin signals and to regulate food intake. We propose a mathematical model of the leptin-leptin receptors system, based on the assumption that leptin is a regulator of its own receptor activity, and investigate its qualitative behavior. Based on current knowledge and previous models developed for body weight dynamics in rodents, the model includes the dynamics of leptin, leptin receptors and the regulation of food intake and body weight. It displays two stable equilibria, one representing a healthy state and the other one an obese and leptin resistant state. We show that a constant leptin injection can lead to leptin resistance and that a temporal variation in some parameter values influencing food intake can induce a change of equilibrium and a pathway to leptin resistance and obesity. Copyright © 2015. Published by Elsevier Inc.

  7. Thermoplastic composite matrices with improved solvent resistance

    NASA Technical Reports Server (NTRS)

    Hergenrother, P. M.; Jensen, B. J.; Havens, S. J.

    1984-01-01

    In order to improve solvent resistance of aromatic thermoplastic polymers, ethynyl-terminated aromatic sulfone polymers (ETS), sulfone/ester polymers (SEPE) containing pendent ethynyl groups, and phenoxy resin containing pendent ethynyl groups are synthesized. Cured polysulfones and phenoxy resins containing ethynyl groups on the ends or pendent on the molecules exhibited systematic behavior in solvent resistance, film flexibility, and toughness as a function of crosslink density. The film and composite properties of a cured solvent-resistant ETS were better than those of a commercially available solvent sensitive polysulfone. The study was part of a NASA program to better understand the trade-offs between solvent resistance, processability and mechanical properties which may be useful in designing composite structures for aerospace vehicles.

  8. Linear response of zero-resistance states

    NASA Astrophysics Data System (ADS)

    Breitkreiz, Maxim

    2017-08-01

    A two-dimensional electron system in the presence of a magnetic field and microwave irradiation can undergo a phase transition towards a zero-resistance state (ZRS). A widely used model predicts the ZRS to be a domain state, which responds to applied dc voltages or dc currents by slightly changing the domain structure. Here we propose an alternative response scenario, according to which the domain pattern remains unchanged. Surprisingly, a fixed domain pattern does not destroy zero-resistance, provided that the resistance is direction independent. Otherwise, if the symmetry of the domain pattern allows a direction dependence of the resistance, the domain state can be dissipative. We give examples for both situations and simulate the response behavior numerically.

  9. Thermoplastic composite matrices with improved solvent resistance

    NASA Technical Reports Server (NTRS)

    Hergenrother, P. M.; Jensen, B. J.; Havens, S. J.

    1984-01-01

    In order to improve solvent resistance of aromatic thermoplastic polymers, ethynyl-terminated aromatic sulfone polymers (ETS), sulfone/ester polymers (SEPE) containing pendent ethynyl groups, and phenoxy resin containing pendent ethynyl groups are synthesized. Cured polysulfones and phenoxy resins containing ethynyl groups on the ends or pendent on the molecules exhibited systematic behavior in solvent resistance, film flexibility, and toughness as a function of crosslink density. The film and composite properties of a cured solvent-resistant ETS were better than those of a commercially available solvent sensitive polysulfone. The study was part of a NASA program to better understand the trade-offs between solvent resistance, processability and mechanical properties which may be useful in designing composite structures for aerospace vehicles.

  10. Animal studies of addictive behavior.

    PubMed

    Vanderschuren, Louk J M J; Ahmed, Serge H

    2013-04-01

    It is increasingly recognized that studying drug taking in laboratory animals does not equate to studying genuine addiction, characterized by loss of control over drug use. This has inspired recent work aimed at capturing genuine addiction-like behavior in animals. In this work, we summarize empirical evidence for the occurrence of several DSM-IV-like symptoms of addiction in animals after extended drug use. These symptoms include escalation of drug use, neurocognitive deficits, resistance to extinction, increased motivation for drugs, preference for drugs over nondrug rewards, and resistance to punishment. The fact that addiction-like behavior can occur and be studied in animals gives us the exciting opportunity to investigate the neural and genetic background of drug addiction, which we hope will ultimately lead to the development of more effective treatments for this devastating disorder.

  11. Animal Studies of Addictive Behavior

    PubMed Central

    Ahmed, Serge H.

    2013-01-01

    It is increasingly recognized that studying drug taking in laboratory animals does not equate to studying genuine addiction, characterized by loss of control over drug use. This has inspired recent work aimed at capturing genuine addiction-like behavior in animals. In this work, we summarize empirical evidence for the occurrence of several DSM-IV-like symptoms of addiction in animals after extended drug use. These symptoms include escalation of drug use, neurocognitive deficits, resistance to extinction, increased motivation for drugs, preference for drugs over nondrug rewards, and resistance to punishment. The fact that addiction-like behavior can occur and be studied in animals gives us the exciting opportunity to investigate the neural and genetic background of drug addiction, which we hope will ultimately lead to the development of more effective treatments for this devastating disorder. PMID:23249442

  12. Child-resistant and tamper-resistant packaging: A systematic review to inform tobacco packaging regulation.

    PubMed

    Jo, Catherine L; Ambs, Anita; Dresler, Carolyn M; Backinger, Cathy L

    2017-02-01

    We aimed to investigate the effects of special packaging (child-resistant, adult-friendly) and tamper-resistant packaging on health and behavioral outcomes in order to identify research gaps and implications for packaging standards for tobacco products. We searched seven databases for keywords related to special and tamper-resistant packaging, consulted experts, and reviewed citations of potentially relevant studies. 733 unique papers were identified. Two coders independently screened each title and abstract for eligibility. They then reviewed the full text of the remaining papers for a second round of eligibility screening. Included studies investigated a causal relationship between type of packaging or packaging regulation and behavioral or health outcomes and had a study population composed of consumers. Studies were excluded on the basis of publication type, if they were not peer-reviewed, and if they had low external validity. Two reviewers independently coded each paper for study and methodological characteristics and limitations. Discrepancies were discussed and resolved. The review included eight studies: four assessing people's ability to access the contents of different packaging types and four evaluating the impact of packaging requirements on health-related outcomes. Child-resistant packaging was generally more difficult to open than non-child-resistant packaging. Child-resistant packaging requirements have been associated with reductions in child mortality. Child-resistant packaging holds the expectation to reduce tobacco product poisonings among children under six. Published by Elsevier Inc.

  13. Behavioral addictions.

    PubMed

    Robbins, T W; Clark, L

    2015-02-01

    Behavioral addictions are slowly becoming recognized as a valid category of psychiatric disorder as shown by the recent allocation of pathological gambling to this category in DSM-5. However, several other types of psychiatric disorder proposed to be examples of behavioral addictions have yet to be accorded this formal acknowledgment and are dispersed across other sections of the DSM-5. This brief review marks this important point in the evolution of this concept and looks to future investigation of behavioral addictions with the theoretical frameworks currently being used successfully to investigate substance addiction and obsessive-compulsive disorder, in a potentially new spectrum of impulsive-compulsive disorders. Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. Resistance switching behavior of atomic layer deposited SrTiO3 film through possible formation of Sr2Ti6O13 or Sr1Ti11O20 phases

    NASA Astrophysics Data System (ADS)

    Lee, Woongkyu; Yoo, Sijung; Yoon, Kyung Jean; Yeu, In Won; Chang, Hye Jung; Choi, Jung-Hae; Hoffmann-Eifert, Susanne; Waser, Rainer; Hwang, Cheol Seong

    2016-02-01

    Identification of microstructural evolution of nanoscale conducting phase, such as conducting filament (CF), in many resistance switching (RS) devices is a crucial factor to unambiguously understand the electrical behaviours of the RS-based electronic devices. Among the diverse RS material systems, oxide-based redox system comprises the major category of these intriguing electronic devices, where the local, along both lateral and vertical directions of thin films, changes in oxygen chemistry has been suggested to be the main RS mechanism. However, there are systems which involve distinctive crystallographic phases as CF; the Magnéli phase in TiO2 is one of the very well-known examples. The current research reports the possible presence of distinctive local conducting phase in atomic layer deposited SrTiO3 RS thin film. The conducting phase was identified through extensive transmission electron microscopy studies, which indicated that oxygen-deficient Sr2Ti6O13 or Sr1Ti11O20 phase was presumably present mainly along the grain boundaries of SrTiO3 after the unipolar set switching in Pt/TiN/SrTiO3/Pt structure. A detailed electrical characterization revealed that the samples showed typical bipolar and complementary RS after the memory cell was unipolar reset.

  15. Resistance switching behavior of atomic layer deposited SrTiO3 film through possible formation of Sr2Ti6O13 or Sr1Ti11O20 phases

    PubMed Central

    Lee, Woongkyu; Yoo, Sijung; Yoon, Kyung Jean; Yeu, In Won; Chang, Hye Jung; Choi, Jung-Hae; Hoffmann-Eifert, Susanne; Waser, Rainer; Hwang, Cheol Seong

    2016-01-01

    Identification of microstructural evolution of nanoscale conducting phase, such as conducting filament (CF), in many resistance switching (RS) devices is a crucial factor to unambiguously understand the electrical behaviours of the RS-based electronic devices. Among the diverse RS material systems, oxide-based redox system comprises the major category of these intriguing electronic devices, where the local, along both lateral and vertical directions of thin films, changes in oxygen chemistry has been suggested to be the main RS mechanism. However, there are systems which involve distinctive crystallographic phases as CF; the Magnéli phase in TiO2 is one of the very well-known examples. The current research reports the possible presence of distinctive local conducting phase in atomic layer deposited SrTiO3 RS thin film. The conducting phase was identified through extensive transmission electron microscopy studies, which indicated that oxygen-deficient Sr2Ti6O13 or Sr1Ti11O20 phase was presumably present mainly along the grain boundaries of SrTiO3 after the unipolar set switching in Pt/TiN/SrTiO3/Pt structure. A detailed electrical characterization revealed that the samples showed typical bipolar and complementary RS after the memory cell was unipolar reset. PMID:26830978

  16. Pneumococcal resistance to antibiotics.

    PubMed Central

    Klugman, K P

    1990-01-01

    The geographic distribution of pneumococci resistant to one or more of the antibiotics penicillin, erythromycin, trimethoprim-sulfamethoxazole, and tetracycline appears to be expanding, and there exist foci of resistance to chloramphenicol and rifampin. Multiply resistant pneumococci are being encountered more commonly and are more often community acquired. Factors associated with infection caused by resistant pneumococci include young age, duration of hospitalization, infection with a pneumococcus of serogroup 6, 19, or 23 or serotype 14, and exposure to antibiotics to which the strain is resistant. At present, the most useful drugs for the management of resistant pneumococcal infections are cefotaxime, ceftriaxone, vancomycin, and rifampin. If the strains are susceptible, chloramphenicol may be useful as an alternative, less expensive agent. Appropriate interventions for the control of resistant pneumococcal outbreaks include investigation of the prevalence of resistant strains, isolation of patients, possible treatment of carriers, and reduction of usage of antibiotics to which the strain is resistant. The molecular mechanisms of penicillin resistance are related to the structure and function of penicillin-binding proteins, and the mechanisms of resistance to other agents involved in multiple resistance are being elucidated. Recognition is increasing of the standard screening procedure for penicillin resistance, using a 1-microgram oxacillin disk. PMID:2187594

  17. Charge relaxation resistance at atomic scale: An ab initio calculation

    NASA Astrophysics Data System (ADS)

    Wang, Bin; Wang, Jian

    2008-06-01

    We report an investigation of ac quantum transport properties of a nanocapacitor from first principles. At low frequencies, the nanocapacitor is characterized by a static electrochemical capacitance Cμ and the charge relaxation resistance Rq . We carry out a first principle calculation within the nonequilibrium Green’s function formalism. In particular, we investigate charge relaxation resistance of a single carbon atom as well as two carbon atoms in a nanocapacitor made of a capped carbon nanotube (CNT) and an alkane chain connected to a bulk Si. The nature of charge relaxation resistance is predicted for this nanocapacitor. Specifically, we find that the charge relaxation resistance shows resonant behavior and it becomes sharper as the distance between plates of nanocapacitor increases. If there is only one transmission channel dominating the charge transport through the nanocapacitor, the charge relaxation resistance Rq is half of resistance quantum h/2e2 . This result shows that the theory of charge relaxation resistance applies at atomic scale.

  18. The role of poverty in antimicrobial resistance.

    PubMed

    Planta, Margaret B

    2007-01-01

    Antimicrobial resistance is a worldwide problem that has deleterious long-term effects as the development of drug resistance outpaces the development of new drugs. Poverty has been cited by the World Health Organization as a major force driving the development of antimicrobial resistance. In developing countries, factors such as inadequate access to effective drugs, unregulated dispensing and manufacture of antimicrobials, and truncated antimicrobial therapy because of cost are contributing to the development of multidrug-resistant organisms. Within the United States, poverty-driven practices such as medication-sharing, use of "leftover" antibiotics, and the purchase and use of foreign-made drugs of questionable quality are likely contributing to antimicrobial resistance. However, there is currently a dearth of studies in the United States analyzing the socioeconomic and behavioral factors behind antimicrobial resistance in United States communities. Further studies of these factors, with an emphasis on poverty-driven practices, need to be undertaken in order to fully understand the problem of antimicrobial resistance in the United States and to develop effective intervention to combat this problem.

  19. Cell shunt resistance and photovoltaic module performance

    SciTech Connect

    McMahon, T.J.; Basso, T.S.; Rummel, S.R.

    1996-05-01

    Shunt resistance of cells in photovoltaic modules can affect module power output and could indicate flawed manufacturing processes and reliability problems. The authors describe a two-terminal diagnostic method to directly measure the shunt resistance of individual cells in a series-connected module non-intrusively, without deencapsulation. Peak power efficiency vs. light intensity was measured on a 12-cell, series-connected, single crystalline module having relatively high cell shunt resistances. The module was remeasured with 0.5-, 1-, and 2-ohm resistors attached across each cell to simulate shunt resistances of several emerging technologies. Peak power efficiencies decreased dramatically at lower light levels. Using the PSpice circuit simulator, the authors verified that cell shunt and series resistances can indeed be responsible for the observed peak power efficiency vs. intensity behavior. The authors discuss the effect of basic cell diode parameters, i.e., shunt resistance, series resistance, and recombination losses, on PV module performance as a function of light intensity.

  20. Effect of Inquiry-Based Learning Approach on Student Resistance in a Science and Technology Course

    ERIC Educational Resources Information Center

    Sever, Demet; Guven, Meral

    2014-01-01

    The aim of this study was to identify the resistance behaviors of 7th grade students exhibited during their Science and Technology course teaching-learning processes, and to remove the identified resistance behaviors through teaching-learning processes that were constructed based on the inquiry-based learning approach. In the quasi-experimentally…