WorldWideScience

Sample records for behavioral resistance

  1. Resistance to extinction and behavioral momentum

    OpenAIRE

    Nevin, John A.

    2012-01-01

    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 ...

  2. Resistance to extinction and behavioral momentum.

    Science.gov (United States)

    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

    Science.gov (United States)

    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. Utilizing Motivational Interviewing to Address Resistant Behaviors in Clinical Supervision

    Science.gov (United States)

    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.

  5. Shear-resistant behavior of light composite shear wall

    Institute of Scientific and Technical Information of China (English)

    李升才; 董毓利

    2015-01-01

    Shear test results for a composite wall panel in a light composite structure system are compared with test results for shear walls in Japan. The analysis results show that this kind of composite wall panel works very well, and can be regarded as a solid panel. The composite wall panel with a hidden frame is essential for bringing its effect on shear resistance into full play. Comprehensive analysis of the shear-resistant behavior of the composite wall panel suggests that the shear of the composite shear wall panel can be controlled by the cracking strength of the web shearing diagonal crack.

  6. Shear-Resistant Behavior Analysis of Light Composite Shear Walls

    Institute of Scientific and Technical Information of China (English)

    李升才; 江见鲸; 于庆荣

    2002-01-01

    Shear test results for a composite wall panel in a light composite structure system are compared with test results for shear walls in Japan in this paper. The analysis results show that this kind of composite wall panel works very well, and can be regarded as a solid panel. The composite wall panel with a hidden frame is essential for bringing its effect on shear resistance into full play. Comprehensive analysis of the shear-resistant behavior of the composite wall panel suggests that the shear of the composite shear wall panel can be controlled by the cracking strength of the web shearing diagonal crack.

  7. Client Resistance as Predicted by Therapist Behavior: A Study of Sequential Dependence.

    Science.gov (United States)

    Bischoff, Mary M.; Tracey, Terence J. G.

    1995-01-01

    Examines the relation of client resistant behavior to therapist directive behavior in a sample of ten archival therapy sessions. Results indicated an overall trend, with therapist directive behavior slightly increasing the probability of subsequent client resistance. No similar effect of client behavior on subsequent therapist behavior was found.…

  8. Resistance in Cognitive Behavioral Therapy and Motivational Interviewing Techniques

    Directory of Open Access Journals (Sweden)

    Nurcihan Alpaydin

    2016-06-01

    Full Text Available As is valid for each psychotherapy method, the factors such as whether the therapy is appropriate and sufficient, whether the client is ready to therapy, duration and frequency of the therapy shall determine the success of the treatment also for clients whom are treated with cognitive-behavioral therapy. However, while considering these factors, the concept of resistance should not be ignored. The aim of this article is to understand the underlying causes of the resistance for cognitive-behavioral therapy and to make suggestions on how to manage it. In this context, motivational interviewing techniques will also be explained in detail. [Psikiyatride Guncel Yaklasimlar - Current Approaches in Psychiatry 2016; 8(2: 94-101

  9. Bipolar resistive switching behaviors of ITO nanowire networks

    Directory of Open Access Journals (Sweden)

    Qiang Li

    2016-02-01

    Full Text Available We have fabricated indium tin oxide (ITO nanowire (NW networks on aluminum electrodes using electron beam evaporation. The Ag/ITO-NW networks/Al capacitor exhibits bipolar resistive switching behavior. The resistive switching characteristics of ITO-NW networks are related to the morphology of NWs. The x-ray photoelectron spectroscopy was used to obtain the chemical nature from the NWs surface, investigating the oxygen vacancy state. A stable switching voltages and a clear memory window were observed in needle-shaped NWs. The ITO-NW networks can be used as a new two-dimensional metal oxide material for the fabrication of high-density memory devices.

  10. INVESTIGATION OF THERMAL BEHAVIOR OF MULTILAYERED FIRE RESISTANT STRUCTURE

    OpenAIRE

    R. GUOBYS; V. Vekteris; V. MOKSHIN

    2016-01-01

    This paper presents experimental and numerical investigations of thermal behavior under real fire conditions of new generation multilayered fire resistant structure (fire door, dimensions H × W × D: 2090 × 980 × 52 mm) combining high strength and fire safety. This fire door consists of two steel sheets (thickness 1.5 and 0.7 mm) with stone wool ( = 33 kg/m3, k = 0.037 W/mK, E = 5000 N/m2,  = 0.2) insulating layer in between. One surface of the structure was heated in fire furnace for spe...

  11. Flux flow pinning and resistive behavior in superconducting networks

    Energy Technology Data Exchange (ETDEWEB)

    Teitel, S.

    1990-10-01

    We have studied the behavior of superconducting networks in terms of XY and Coulomb gas models. The dynamics of frustrated Josephson junction arrays has been simulated, with a view toward understanding the effects of vortex correlations on flux flow resistance. Randomness has been introduced, and its effects on the superconducting transition, and vortex mobility, have been studied. A three dimensional network has been simulated to study the effects of vortex line entanglement in high temperature superconductors. Preliminary calculations are in progress. The two dimensional classical Coulomb gas where charges map onto vortices in the superconducting network, has been simulated. The melting transitions of ordered charge (vortex) lattices have been studied, and we find clear evidence that these transitions do not have the critical behavior expected from standard symmetry analysis.

  12. INVESTIGATION OF THERMAL BEHAVIOR OF MULTILAYERED FIRE RESISTANT STRUCTURE

    Directory of Open Access Journals (Sweden)

    R. GUOBYS

    2016-09-01

    Full Text Available This paper presents experimental and numerical investigations of thermal behavior under real fire conditions of new generation multilayered fire resistant structure (fire door, dimensions H × W × D: 2090 × 980 × 52 mm combining high strength and fire safety. This fire door consists of two steel sheets (thickness 1.5 and 0.7 mm with stone wool ( = 33 kg/m3, k = 0.037 W/mK, E = 5000 N/m2,  = 0.2 insulating layer in between. One surface of the structure was heated in fire furnace for specified period of time of 60 min. Temperature and deformation of opposite surface were measured from outside at selected measuring points during fire resistance test. Results are presented as temperature-time and thermal deformation-time graphs. Experimental results were compared with numerical temperature field simulation results obtained from SolidWorks®Simulation software. Numerical results were found to be in good agreement with experimental data. The percent differences between door temperatures from simulation and fire resistance test don’t exceed 8%. This shows that thermal behaviour of such multilayered structures can be investigated numerically, thus avoiding costly and time-consuming fire resistance tests. It is established that investigated structure should be installed in a way that places thicker steel sheet closer to the potential heat source than thinner one. It is also obtained that stone wool layer of higher density should be used to improve fire resistance of the structure.

  13. Induced electromagnetic stirring behavior in a resistance spot weld nugget

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    A multi-physics hybrid numerical model,which couples electric,magnetic,thermal and flow fields,was used to investigate electromagnetic stirring behavior in a resistance spot weld nugget.The differences of two kinds of different excitation inputs,i.e.,a sinusoidal current and its root-mean-square(RMS) value,were studied to examine if they could produce equivalent electromagnetic stirring effects in the weld nugget.Research showed that the two types of current inputs could produce almost identical fluid flow and heat transfer patterns and consistent evolution of flow and thermal fields in the nugget.At the end of the welding cycles,the maximum flow velocity and temperature between the two inputs differed by 11.6% and 0.3%,respectively.Therefore,the RMS current can be assumed to produce an approximately equivalent electromagnetic stirring effect with the sinusoidal current,and can be used in the future research to greatly improve the solution efficiency of the electromagnetic stirring behavior in the resistance spot weld nugget.

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

    Directory of Open Access Journals (Sweden)

    Wang J

    2016-08-01

    Full Text Available Jihui Wang, Qinling Wei, Xiaoli Wu, Zhiyong Zhong, Guanying Li Department of Psychiatry, The Third Affiliated Hospital of Sun-Yat Sen University, Guangzhou, Guangdong, People’s Republic of China 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. Keywords: brief behavioral treatment, treatment-resistant, insomnia

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

    Science.gov (United States)

    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.

  16. Oviposition Behaviors in Relation to Rotation Resistance in the Western Corn Rootworm

    NARCIS (Netherlands)

    Knolhoff, L.M.; Glas, J.J.; Spencer, J.L.; Berenbaum, M.R.

    2010-01-01

    Across a large area of the midwestern United States Corn Belt, the western corn rootworm beetle (Diabrotica virgifera virgifera LeConte, Coleoptera: Chrysomelidae) exhibits behavioral resistance to annual crop rotation. Resistant females exhibit increased locomotor activity and frequently lay eggs i

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

    Science.gov (United States)

    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

  18. Flux Flow, Pinning, and Resistive Behavior in Superconducting Networks

    Energy Technology Data Exchange (ETDEWEB)

    Stephen Teitel

    2005-05-03

    Numerical simulators are used to study the behavior of interacting quantized vortices and vortex lines in superconducting networks, films, and three dimensional bulk samples. An emphasis is on the explanation of the phenomenological behavior of the ''high-Tc'' copper-oxide superconductors and related model systems.

  19. Magnetohydrodynamic behaviors in a resistance spot weld nugget under different welding currents

    Institute of Scientific and Technical Information of China (English)

    S.; Jack; HU

    2008-01-01

    Magnetohydrodynamic behaviors in a resistance spot weld nugget under different welding currents are investigated based on a multiphysics coupled numerical model, which incorporates phase change and variable electrical contact resis-tances at faying surface and electrode-workpiece contact surface. The patterns of the flow field and thermal field at the end of the welding phase under different welding currents are obtained. The evolutions of fluid flow and heat transfer during the whole welding process are also revealed systematically. The analysis results are also compared with a traditional electrothermal coupled model to obtain the quantitative effects of the magnetohydrodynamic behaviors on the resistance spot weld nugget formation.

  20. Thermal Behavior of Nano-TiO2 in Fire-Resistant Coating

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The dispersion state of nano-TiO2 particles was studied by using transmission electron microscopy (TEM)and Fourier transform infrared spectroscopy (FT-IR). Nanoparticles can be fully dispersed by specific hyperdispersant. The improvement of nano-TiO2 in thermal behavior and flame retardation of acrylic polymer and fire-resistant coating was investigated by differential thermal analysis (DTA), thermogravimetry (TG)and fire-resistant time test. It is demonstrated that nano-TiO2 is helpful for enhancing the thermal stability,anti-oxidation and fire-resistant properties of acrylic polymer and fire-resistant coating.

  1. Anomalous behavior of electrical resistivity in NdFe{sub 11}Ti

    Energy Technology Data Exchange (ETDEWEB)

    Tajabor, N.; Alinejad, M.R. [Department of Physics, Faculty of Science, Ferdowsi University of Mashhad (Iran); Amirabadizadeh, A. [Department of Physics, Faculty of Science, Ferdowsi University of Mashhad (Iran); Department of Physics, Faculty of Science, University of Birjand, Birjand (Iran); Pourarian, F. [Carnegie Mellon Research Institute, Carnegie Mellon University, Pittsburgh, Pennsylvania, 15219 (United States)

    2004-05-01

    The electrical resistivity, {rho}, and temperature derivative of resistivity (d/dT) of polycrystalline NdFe{sub 11}Ti are investigated. The resistivity exhibits an anomalous behavior at about 160 K and 220 K. These anomalies attributed to spin reorientation phenomena originate from two magnetic phase transition. A modified theoretical model for electrical resistivity, {rho} and d{rho}/dT, behavior in the spin reorientation temperature (T{sub SR}) region is presented. The results suggest that the average magnetic moment at T{sub SR1} {proportional_to}160 K is aligned along a cone angle and at T{sub SR2} {proportional_to}220 K along c-axis. The temperature dependence of ac-susceptibility, {chi}{sub ac}(T), is presented. The results show the existence of the spin reorientation related to a magnetic phase transition. (copyright 2004 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

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

    Science.gov (United States)

    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.

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

    Directory of Open Access Journals (Sweden)

    Prieto-Hicks X

    2012-09-01

    Full Text Available Sarah Hamill-Skoch,1 Paul Hicks,2 Ximena Prieto-Hicks11Department of Psychiatry, 2Department of Family and Community Medicine, University of Arizona, Tuscon, AZ, USAAbstract: 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.Keywords: cognitive behavior therapy, treatment-resistant depression, adolescent depression

  4. Magnetohydrodynamic behaviors in a resistance spot weld nugget Under different welding currents

    Institute of Scientific and Technical Information of China (English)

    LI YongBing; LIN ZhongQin; S. Jack HU; CHEN GuanLong

    2008-01-01

    Magnetohydrodynamic behaviors in a resistance spot weld nugget under different welding currents are investigated based on a multiphysics coupled numerical model, which incorporates phase change and variable electrical contact resis- tances at faying surface and electrode-workpiece contact surface. The patterns of the flow field and thermal field at the end of the welding phase under different welding currents are obtained. The evolutions of fluid flow and heat transfer during the whole welding process are also revealed systematically. The analysis results are also compared with a traditional electrothermal coupled model to obtain the quantitative effects of the magnetohydrodynamic behaviors on the resistance spot weld nugget formation.

  5. Using different ELECTRE methods in strategic planning in the presence of human behavioral resistance

    Directory of Open Access Journals (Sweden)

    A. S. Milani

    2006-01-01

    Full Text Available In the multicriteria strategic planning of an organization, management should often be aware of employees' resistance to change before making new decisions; otherwise, a chosen strategy, though technologically acceptable, may not be efficient in the long term. This paper, using a sample case study within an organization, shows how different versions of ELECTRE methods can be used in choosing efficient strategies that account for both human behavioral resistance and technical elements. The effect of resistance from each subsystem of the organization is studied to ensure the reliability of the chosen strategy. The comparison of results from a select number of compensatory and noncompensatory models (ELECTRE I, III, IV, IS; TOPSIS; SAW; MaxMin suggests that when employee resistance is a decision factor in the multicriteria strategic planning problem, the models can yield low-resistance strategies; however, ELECTRE seems to show more reasonable sensitivity.

  6. Corrosion behavior of corrosion resistant alloys in stimulation acids

    Energy Technology Data Exchange (ETDEWEB)

    Cheldi, Tiziana [ENI E and P Division, 20097 San Donato Milanese Milano (Italy); Piccolo, Eugenio Lo; Scoppio, Lucrezia [Centro Sviluppo Materiali, via Castel Romano 100, 00128 Rome (Italy)

    2004-07-01

    In the oil and gas industry, selection of CRAs for downhole tubulars is generally based on resistance to corrosive species in the production environment containing CO{sub 2}, H{sub 2}S, chloride and in some case elemental sulphur. However, there are non-production environments to which these materials must also be resistant for either short term or prolonged duration; these environments include stimulation acids, brine and completion fluids. This paper reports the main results of a laboratory study performed to evaluate the corrosion and stress corrosion behaviour to the acidizing treatments of the most used CRAs for production tubing and casing. Laboratory tests were performed to simulate both 'active' and 'spent' acids operative phases, selecting various environmental conditions. The selected steel pipes were a low alloyed steel, martensitic, super-martensitic, duplex 22 Cr, superduplex 25 Cr and super-austenitic stainless steels (25 Cr 35 Ni). Results obtained in the 'active' acid environments over the temperature range of 100-140 deg. C, showed that the blend acids with HCl at high concentration and HCl + HF represented too much severe conditions, where preventing high general corrosion and heavy localised corrosion by inhibition package becomes very difficult, especially for duplex steel pipe, where, in some case, the specimens were completely dissolved into the solution. On the contrary, all steels pipes were successfully protected by inhibitor when organic acid solution (HCOOH + CH{sub 3}COOH) were used. Furthermore, different effectiveness on corrosion protection was showed by the tested inhibitors packages: e.g. in the 90% HCl at 12% + 10 CH{sub 3}COOH acid blend. In 'spent' acid environments, all steel pipes showed to be less susceptible to the localised and general corrosion attack. Moreover, no Sulphide Stress Corrosion Cracking (SSC) was observed. Only one super-austenitic stainless steel U-bend specimen showed

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

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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…

  12. Resistance to Temptation and Moral Judgment: Behavioral Correlates of Kohlberg's Measure of Moral Judgment.

    Science.gov (United States)

    Nelsen, Edward A.; And Others

    This study was designed to assess and compare the roles of intelligence and moral judgment in relation to patterns of behavior in temptation situations. Six Resistance to Temptation (RTT) tasks were administered to 106 sixth grade students. One year later, four Kohlberg Moral Judgment (MJ) tasks were administered to 100 of the same subjects. IQ…

  13. In-Plane Crystallinity Effect on the Unipolar Resistance Switching Behavior of NiO Thin Film.

    Science.gov (United States)

    Kim, Il Tae; Hur, Jaehyun; Chae, Seung Chul

    2016-02-01

    We report on the resistance switching behavior of high quality NiO thin films grown on Pt(111)/SiOx/Si and Pt(111)/Al2O3 crystals. Polarity independent resistance switching, i.e., unipolar resistance switching exhibited a substrate crystallinity dependence during the resistance switching. The unipolar resistance switching was observed commonly in NiO film grown on both substrates. High resistance state of NiO thin film without in-plane crystallinity showed higher resistance than that of NiO films with in-plane crystallinity. The NiO thin film without in-plane crystallinity also required high set voltages for the resistance switching from high resistance state to low resistance state and showed nonlinear I-V characteristics at high voltage region before the resistance switching.

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

    Science.gov (United States)

    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.

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

    Directory of Open Access Journals (Sweden)

    Jablonski Rita A

    2011-11-01

    Full Text Available Abstract 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

  16. Unique behavioral characteristics and microRNA signatures in a drug resistant epilepsy model.

    Directory of Open Access Journals (Sweden)

    Jangsup Moon

    Full Text Available 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.

  17. Electrical Resistance Behavior of Vinylester Composites Filled with Glass-carbon Hybrid Fibers

    Institute of Scientific and Technical Information of China (English)

    WANG Jun; ZHANG Lianmeng; XU Renxin; DUAN Huajun; YANG Xiaoli; WANG Xiang

    2009-01-01

    Vinylester (bismethacryloxy derivative of a bisphenol-A type EP resin, VE) composites with glass-carbon hybrid fibers (CF-GF) weight fraction of 50%, were prepared by the compress molding method. The distribution of carbon fiber in the hybrids was observed by stereomicroscope. The electrical resistance behavior of the composites filled with different carbon fiber (CF) weight contents (0.5% to 20%) was studied. The experimental results show that the electrical resistance behaviors of CF-GF/VE composites are different with those of CF/VE composites because carbon fibers' conducting networks are broken by the glass fibers in the CF-GF/VE composites. The carbon fibers distribute uniformly in the networks of glass fibers (GF) like single silk and form the semi-continuous conducting networks. Composite filled with GF-CF hybrid has a higher percolation threshold than that filled with pure CF. At that time, the resistivity of CF-GF/VE composites varies little with the temperature increasing. The temperature coefficient of resistivity in GF-CF/VE composite is less than 317 ppm and the variation of the resistivity after ten thermal cycles from 20 ℃to 240 ℃ is less than 1.96%.

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

    Science.gov (United States)

    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.

  19. Oxide stoichiometry-controlled TaOx-based resistive switching behaviors

    Science.gov (United States)

    Baek, Gwang Ho; Lee, Ah Rahm; Kim, Tae Yoon; Im, Hyun Sik; Hong, Jin Pyo

    2016-10-01

    We examine the influence of variable oxygen concentration in TaOx active layers on the forming process and bipolar resistive switching (BRS) features of TaOx-based resistive switching cells. TaOx active layers prepared using various rf sputtering powers were systematically analyzed to identify the relation between initial compositions and BRS behavior. Proper control of oxygen vacancy concentration was clearly identified as a basic factor in ensuring typical BRS features without affecting the structural properties. We describe the possible origins of both conduction and switching based on the variation of oxygen concentrations initially provided by the growth conditions.

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

    Science.gov (United States)

    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.

  1. Studying the mechanical behavior of a plastic, shock-resisting, antitank landmine.

    Science.gov (United States)

    Kirkpatrick Alberts, W C; Waxier, Roger; Sabatier, James M

    2006-12-01

    Modal behavior in landmines has recently become a topic of interest for acoustic landmine detection. It is well known that landmines exhibit mechanical resonance behavior that enhances the soil velocity over a buried landmine. Recent experimental work by Zagrai et al. [A. Zagrai, D. Donskoy, and A. Ekimov, J. Acoust. Soc. Am. 118 (6), 3619-3628 (2005)] demonstrates the existence of structural modes in several landmines. The work reported herein parallels the work of Zagrai et al. in studying the structural modes of the pressure plate of a plastic, cylindrically symmetric, antitank landmine. The pressure plate is considered to act as an elastically supported thin elastic plate. An observed perturbation of the first symmetric mode of the pressure plate is caused by the landmine's shock-resisting mechanism. This is validated by a lumped element model for the first symmetric mode coupled to the shock-resisting mechanism.

  2. Surface effects of electrode-dependent switching behavior of resistive random-access memory

    KAUST Repository

    Ke, Jr Jian

    2016-09-26

    The surface effects of ZnO-based resistive random-access memory (ReRAM) were investigated using various electrodes. Pt electrodes were found to have better performance in terms of the device\\'s switching functionality. A thermodynamic model of the oxygen chemisorption process was proposed to explain this electrode-dependent switching behavior. The temperature-dependent switching voltage demonstrates that the ReRAM devices fabricated with Pt electrodes have a lower activation energy for the chemisorption process, resulting in a better resistive switching performance. These findings provide an in-depth understanding of electrode-dependent switching behaviors and can serve as design guidelines for future ReRAM devices.

  3. Effects of Contact Resistance on Heat Transfer Behaviors of Fibrous Insulation

    Institute of Scientific and Technical Information of China (English)

    Zhao Shuyuan; Zhang Boming; Du Shanyi

    2009-01-01

    In this article, a numerical model combining conduction and radiation is developed based on two flux approximation to predict the heat transfer behavior of fibrous insulation used in thermal protection systems. Monte Carlo method is utilized to determine the modified radiative properties with experimentally measured transient external temperature as high as 1 000 K. It is found that the estimated radiative properties become time-independent after about t = 3 000 s. By comparing the predicted to the measured results in transient state, the contact resistance exerts significant influences upon the temperature distribution in the specimen. Results show that the averaged absolute deviation is 3.25% when contact resistance is neglected in heat transfer model, while 1.82% with no contact resistance.

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

    Science.gov (United States)

    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 pBehavioral analysis revealed that animals demonstrated profound anxiety-like behavior as observed by performance on the elevated-plus maze with time spent by the mice in the open arm (ANOVA p = 0.000; NCS:HA7 p = 0.004; NCS:OS-HA7 p = 1.000; HA7:OS-HA7 p = 0.0001) as well as entries in the open arm (ANOVA p = 0.039; NCS:HA7 p = 0.041; HA7:OS-HA7 p = 0.221; NCS:OS-HA7 p = 1.000). Open-field behavior, a measure of general locomotion and exploration, revealed statistically significant differences between groups in locomotion as a measure of transitions across quadrant boundaries. Additionally, the open-field assay revealed decreased exploration as well as decreased rearing in HA7 and OS-HA7 fed mice demonstrating a

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

    Directory of Open Access Journals (Sweden)

    Mark Lyte

    Full Text Available 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

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

    Science.gov (United States)

    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.

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

    Directory of Open Access Journals (Sweden)

    Ana Teresa P. Carvalho

    2014-01-01

    Full Text Available 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

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

    Science.gov (United States)

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

    2016-06-01

    The multi-step resistive switching (RS) behavior of a unipolar Pt/Li0.06Zn0.94O/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+ ion diffusion (2-, 3-, and 4-step RESET behaviors) under high electric fields.

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

    Science.gov (United States)

    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.

  10. Antiepileptic, behavioral, and antidepressant effects of adjuvant lamotrigine therapy in drug-resistant epilepsy

    Directory of Open Access Journals (Sweden)

    Martinović Žarko J.

    2004-01-01

    Full Text Available Aim. To evaluate the behavioral effects of lamotrigine as add-on therapy in treatment-resistant epilepsy. Methods. An open, prospective, long-term study of lamotrigine as adjuvant therapy was performed in 56 patients with drug-resistant epilepsy (female/male ratio 35/21, age range 16-51 years. All the patients kept seizure diaries, and electroencephalograms were recorded at baseline and during 24 months of the treatment. Quality of life questionnaire, Hamilton depression scale (HMD, Beck depression scale (BDI, and Hamilton anxiety scale (HMA were used before and during lamotrigine therapy. Comparative assessments were made in an age- and sex-matched control group treated with other antiepileptic drugs. Results. Overall, seizure control was improved in 55.3% of the patients, remained unchanged in 39.3%, and deteriorated in 5.4%. Improvement in some quality of life measures occurred in 50% of the patients. The HMD subscales and BDI scale showed significant improvement in lamotrigine treated patients compared to the control group (ANOVA, p < 0.01. Negative behavioral effects occurred in 10.7% of the patients. Conclusion. Lamotrigine demonstrated significant antiepileptic long-term efficacy, and its positive effects on the mood and quality of life, which surpassed the negative behavioral effects, and contributed highly to the favorable treatment outcome.

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

    Institute of Scientific and Technical Information of China (English)

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

    2016-01-01

    The recrystallization behavior of deformed Ti40 alloy during a heat-treatment process was studied using electron backscatter dif-fraction 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 proc-ess 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 av-erage grain size. The special recrystallization behavior of Ti40 alloy is mainly a consequence of the alloy’s highβ-stabilized elemental con-tent and high solution strength of theβ-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 microstruc-tures and mechanical properties.

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

    Science.gov (United States)

    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.

  13. Study on the Thermal Fatigue Behavior of Hot Deformed Wear Resistance Cast Iron and Effect of Carbide

    Institute of Scientific and Technical Information of China (English)

    Dong Litao; Liu Rongchang; Li Xingyuan; Chen Xiuhong

    2007-01-01

    The thermal fatigue behavior of wear resistance cast iron with different quantity of deformation has been investigated. The results show that eutectic carbide is the main location and passage for initiation and extension of thermal fatigue cracks, approving that the more serious, the carbide breaks. The higher thermal fatigue resistance of wear resistance cast iron will be and thermal fatigue fracture belongs mainly to brittleness.

  14. Combining the Converse Humidity/Resistance Response Behaviors of RGO Films for Flexible Logic Devices

    KAUST Repository

    Tai, Yanlong

    2017-03-23

    Carbon nanomaterials have excellent humidity sensing performance. Here, we demonstrate that reduced-graphene-oxide- (rGO) based conductive films with different thermal reduction times have gradient and invertible humidity/electrical resistance responses: rGO films (< 11 h, negative response, regarded as a signal of “0”), rGO films (around 11-13 h, balance point) and rGO films (> 13 h, negative response, regarded as a signal of “1”). We propose a new mechanism that describes a “scale”-like model for rGO films to explain these behaviors based on contributions from Ohm-contact resistance and capacitive reactance at interplate junctions, and intrinsic resistances of the nanoplates, respectively. This mechanism is accordingly validated via a series of experiments and electrical impedance spectroscopies, which complement more classical models based on proton conductivity. To explore the practical applications of the converse humidity/resistance responses, three simple flexible logic devices were developed, i) a rGO pattern for humidity-insensitive conductive film, which has the potential to greatly improve the stability of carbon-based electrical device to humidity; ii) a Janus pattern of rGO films for gesture recognition, which is very useful to human/machine interactions; iii) a sandwich pattern of rGO films for 3-dimensional (3D) noncontact sensing, which will be complementary to existing 3D touch technique.

  15. High fat diet produces brain insulin resistance, synaptodendritic abnormalities and altered behavior in mice.

    Science.gov (United States)

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

    2014-07-01

    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 17days or a moderate high fat diet (HFD, 45% kcal by fat) for 8weeks 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-pS(616)), 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.

  16. Critical behavior of electrical resistivity in amorphous Fe–Zr alloys

    Indian Academy of Sciences (India)

    A Perumal

    2001-04-01

    Electrical resistivity (ρ) of the amorphous (a-)Fe100-Zr ( = 8.5, 9.5 and 10) alloys has been measured in the temperature range 77 to 300 K, which embraces the second-order magnetic phase transition at the Curie temperature point . Analysis of the resistivity data particularly in the critical region reveals that these systems have a much wider range of critical region compared to other crystalline ferromagnetic materials. The value of and specific heat critical exponent, has the same values as those determined from our earlier magnetic measurements. The value of for all the present investigated alloys are in close agreement with the values predicted for three-dimensional (3D) Heisenberg ferromagnet systems, which gives contradiction to the earlier results on similar alloys. It is observed from the analysis that the presence of quenched disorder does not have any influence on critical behavior.

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

    OpenAIRE

    2013-01-01

    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...

  18. Precipitation behavior in a nitride-strengthened martensitic heat resistant steel during hot deformation

    Directory of Open Access Journals (Sweden)

    Wenfeng Zhang

    2015-09-01

    Full Text Available The stress relaxation curves for three different hot deformation processes in the temperature range of 750–1000 °C were studied to develop an understanding of the precipitation behavior in a nitride-strengthened martensitic heat resistant steel (Zhang et al., Mater. Sci. Eng. A, 2015 [1]. This data article provides supporting data and detailed information on how to accurately analysis the stress relaxation data. The statistical analysis of the stress peak curves, including the number of peaks, the intensity of the peaks and the integral value of the pumps, was carried out. Meanwhile, the XRD energy spectrum data was also calculated in terms of lattice distortion.

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

    Directory of Open Access Journals (Sweden)

    Adam Robert Nicholls

    2016-01-01

    Full Text Available 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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

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

    2015-03-01

    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 (~103) 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.

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

    Institute of Scientific and Technical Information of China (English)

    芦增星; 高兴森; 严志波; 刘俊明; 宋骁; 赵丽娜; 李忠文; 林远彬; 曾敏; 张璋; 陆旭兵; 吴素娟

    2015-01-01

    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 behaviors are governed by both space-charge-limited conduction (SCLC) and Ohmic behavior. The polarization reversal is able to trigger the conduc-tion 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.

  3. Thermal behavior of resistant starches RS 2, RS 3, and RS 4.

    Science.gov (United States)

    Ratnayake, W S; Jackson, D S

    2008-06-01

    The thermal behaviors of 3 resistant starch types-RS 2, RS 3, and RS 4-were investigated. Samples were heated in excess water to specific temperatures, from 35 to 85 degrees C at 5 degrees C intervals, and freeze-dried. The treated samples were analyzed using SEM, DSC, XRD, and HPSEC to determine the structural changes at granular and molecular levels. Light microscopy was used to determine real-time thermal behavior of the starches. Although the resistant starches did not show significant morphological changes, as revealed by microscopy, they underwent internal structural changes at low temperatures before complete phase transitions occurred. The structural changes were less in RS 2 compared to the other 2 starches studied. The nongranular material of RS 3's crystallinity decreased gradually from 35 to 85 degrees C and showed microscopically visible changes at >80 degrees C. Cross-linking might have prevented RS 4 from becoming completely amorphous within the temperature range (35 to 85 degrees C) tested. The study indicated that the extent of structural changes depended on the treatment temperature and RS type.

  4. Resistivity-Temperature Behavior of CB-Filled HDPE Foaming Composites

    Institute of Scientific and Technical Information of China (English)

    LI Ji-xin; ZHANG Guo; LI Zhuo-shi; WANG Xin-lei; LIU Xiu-qi

    2008-01-01

    High-density polyethylene/carbon black foaming conductive composites were prepared from acetylene black(ACET)and super conductive carbon black(HG-IP)as conductive filler,low-density polyethylene(LDPE)as the second component,ethylene-vinyl acetate(EVA)and ethylene propylene rubber(EPR) as the third component, azobisformamide(AC)as foamer,and dicumyl peroxide(DCP)as cross-linker.The structure and resistivity-temperature behavior of high-density polyethylene(HDPE)/CB foaming conductive composites were investigated.Influences of carbon black,LDPE,EVA,EPR,AC,and DCP on the foaming performance and resistivity-temperature behavior of HDPE/CB foaming conductive composites were also studied.The results reveal that HDPE/CB foaming conductive composite exhibits beaer switching characteristic;ACET-filled HDPE foaming conductive composite displays better positive temperature coefficient(PTC)effect;whereas super conductive carbon black(HG-1P)-filled HDPE foaming conducive composite shows better negative temperature coefficient(NTC)effect.

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

    Directory of Open Access Journals (Sweden)

    Hetrick SE

    2011-08-01

    Full Text Available Sarah E Hetrick1, Georgina R Cox1, Sally N Merry21Orygen Youth Health Research Centre, Centre for Youth Mental Health, Melbourne, Parkville, Victoria, Australia; 2Werry Centre for Child and Adolescent Mental Health, Department of Psychological Medicine, The University of Auckland, Auckland, New ZealandBackground: 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 firstline 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

  6. Behavioral and socioeconomic risk factors associated with probable resistance to ceftriaxone and resistance to penicillin and tetracycline in Neisseria gonorrhoeae in Shanghai.

    Science.gov (United States)

    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 (Pceftriaxone. 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≤0.02). This study is one of the first to use multilevel analysis to consider the association between risk factors for gonorrhea infections and mechanisms of resistance to individual antibiotics. Such information is urgently needed to combat the growing threat of untreatable gonorrhea.

  7. Thermal shock resistance behavior of a functionally graded ceramic: Effects of finite cooling rate

    Directory of Open Access Journals (Sweden)

    Zhihe Jin

    2014-01-01

    Full Text Available This work presents a semi-analytical model to explore the effects of cooling rate on the thermal shock resistance behavior of a functionally graded ceramic (FGC plate with a periodic array of edge cracks. The FGC is assumed to be a thermally heterogeneous material with constant elastic modulus and Poisson's ratio. The cooling rate applied at the FGC surface is modeled using a linear ramp function. An integral equation method and a closed form asymptotic temperature solution are employed to compute the thermal stress intensity factor (TSIF. The thermal shock residual strength and critical thermal shock of the FGC plate are obtained using the SIF criterion. Thermal shock simulations for an Al2O3/Si3N4 FGC indicate that a finite cooling rate leads to a significantly higher critical thermal shock than that under the sudden cooling condition. The residual strength, however, is relatively insensitive to the cooling rate.

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

    Energy Technology Data Exchange (ETDEWEB)

    Behrani, Vikas [Iowa State Univ., Ames, IA (United States)

    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.

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

    Science.gov (United States)

    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.

  10. Behavioral and socioeconomic risk factors associated with probable resistance to ceftriaxone and resistance to penicillin and tetracycline in Neisseria gonorrhoeae in Shanghai.

    Directory of Open Access Journals (Sweden)

    Molly A Trecker

    Full Text Available 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

  11. Unipolar resistive switching behavior in Dy{sub 2}O{sub 3} films for nonvolatile memory applications

    Energy Technology Data Exchange (ETDEWEB)

    Her, Jim-Long [Division of Natural Science, Center for General Education, Chang Gung University, Taoyuan 333, Taiwan (China); Pan, Tung-Ming, E-mail: tmpan@mail.cgu.edu.tw [Department of Electronics Engineering, Chang Gung University, Taoyuan 333, Taiwan (China); Lu, Chih-Hung [Department of Electronics Engineering, Chang Gung University, Taoyuan 333, Taiwan (China)

    2012-06-30

    In this article, we report the forming-free resistive switching behavior of a Ru/Dy{sub 2}O{sub 3}/TaN memory device incorporating a Dy{sub 2}O{sub 3} thin film fabricated entirely through processing at room temperature. We used X-ray diffraction, secondary ion mass spectrometry, and X-ray photoelectron spectroscopy to investigate the structural and chemical features of the Dy{sub 2}O{sub 3} film. The dominant conduction mechanisms in the low- and high-resistance states were ohmic behavior and Poole-Frenkel emission, respectively. The Ru/Dy{sub 2}O{sub 3}/TaN memory device exhibited a high resistance ratio and provided nondestructive readout and reliable data retention. This memory device has a great potential for application in nonvolatile resistive switching memory. - Highlights: Black-Right-Pointing-Pointer The forming-free resistive switching behavior in the Ru/Dy{sub 2}O{sub 3}/TaN device was investigated. Black-Right-Pointing-Pointer The conduction mechanisms of the device are ohmic behavior and Poole-Frenkel emission. Black-Right-Pointing-Pointer This memory device exhibits good electrical characteristics.

  12. Behavior of the electrical resistivity of MnSi at the ferromagnetic phase transition

    Science.gov (United States)

    Petrova, Alla E.; Bauer, E. D.; Krasnorussky, Vladimir; Stishov, Sergei M.

    2006-09-01

    The itinerant helical ferromagnet MnSi reveals a number of remarkable features, which include tricritical phenomena at the phase transition line, Fermi-liquid breakdown, and so-called partial spin order in the paramagnetic state at high pressures. These features, probably interconnected, so far have no satisfactory explanations though several ideas have been suggested. Some current ideas focus on specifics of the spin fluctuations in the paramagnetic phase of MnSi close to the phase transition line. We report here the results of electrical resistivity measurements of a single crystal of MnSi across its ferromagnetic phase transition line at ambient and high pressures. Contrary to previous work in the field we made use of compressed helium as a pressure medium. Sharp peaks of the temperature coefficient of resistivity characterize the transition line. Analysis of these data shows that at pressures to ˜0.35GPa these peaks have fine structure, revealing a shoulder at ˜0.5K above the peak. That confirms the “abnormal” spin behavior in the narrow region above the Curie point and indicates the existence of a nontrivial fluctuation mode in the paramagnetic phase of MnSi . It is symptomatic that this structure disappears at pressures higher than ˜0.35GPa , which was identified earlier as a tricritical point.

  13. Device perspective for black phosphorus field-effect transistors: contact resistance, ambipolar behavior, and scaling.

    Science.gov (United States)

    Du, Yuchen; Liu, Han; Deng, Yexin; Ye, Peide D

    2014-10-28

    Although monolayer black phosphorus (BP), or phosphorene, has been successfully exfoliated and its optical properties have been explored, most of the electrical performance of the devices is demonstrated on few-layer phosphorene and ultrathin BP films. In this paper, we study the channel length scaling of ultrathin BP field-effect transistors (FETs) and discuss a scheme for using various contact metals to change the transistor characteristics. Through studying transistor behaviors with various channel lengths, the contact resistance can be extracted with the transfer length method (TLM). With different contact metals, we find out that the metal/BP interface has different Schottky barrier heights, leading to a significant difference in contact resistance, which is quite different from previous studies of transition metal dichalcogenides (TMDs), such as MoS2, where the Fermi level is strongly pinned near the conduction band edge at the metal/MoS2 interface. The nature of BP transistors is Schottky barrier FETs, where the on and off states are controlled by tuning the Schottky barriers at the two contacts. We also observe the ambipolar characteristics of BP transistors with enhanced n-type drain current and demonstrate that the p-type carriers can be easily shifted to n-type or vice versa by controlling the gate bias and drain bias, showing the potential to realize BP CMOS logic circuits.

  14. A light-modified ferroelectric resistive switching behavior in Ag/BaMoO4/FTO device at ambient temperature

    Science.gov (United States)

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

    2014-12-01

    BaMoO4 powder was prepared by a facile hydrothermal synthesis. And the BaMoO4/FTO device was fabricated by a spin-coated method, in which the thickness of BaMoO4 layer is about 20 μm. The bipolar resistive switching effect has been observed in Ag/BaMoO4/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.

  15. Peeling behavior and spalling resistance of CFRP sheets bonded to bent concrete surfaces

    Science.gov (United States)

    Yuan, Hong; Li, Faping

    2010-05-01

    In this paper, the peeling behavior and the spalling resistance effect of carbon fiber reinforced polymer (CFRP) sheets externally bonded to bent concrete surfaces are firstly investigated experimentally. Twenty one curved specimens and seven plane specimens are studied in the paper, in which curved specimens with bonded CFRP sheets can simulate the concrete spalling in tunnel, culvert, arch bridge etc., whereas plane specimens with bonded CFRP sheets can simulate the concrete spalling in beam bridge, slab bridge and pedestrian bridge. Three kinds of curved specimens with different radii of curvature are chosen by referring to practical tunnel structures, and plane specimens are used for comparison with curved ones. A peeling load is applied on the FRP sheet by loading a circular steel tube placed into the central notch of beam to debond CFRP sheets from the bent concrete surface, meanwhile full-range load-deflection curves are recorded by a MTS 831.10 Elastomer Test System. Based on the experimental results, a theoretical analysis is also conducted for the specimens. Both theoretical and experimental results show that only two material parameters, the interfacial fracture energy of CFRP-concrete interface and the tensile stiffness of CFRP sheets, are needed for describing the interfacial spalling behavior. It is found that the radius of curvature has remarkable influence on peeling load-deflection curves. The test methods and test results given in the paper are helpful and available for reference to the designer of tunnel strengthening.

  16. Fatigue crack growth behaviors of a new burn-resistant highly-stabilized beta titanium alloy

    Institute of Scientific and Technical Information of China (English)

    WU Huan; ZHAO Yongqing; ZENG Weidong; QIAN Li

    2009-01-01

    This article presents the fatigue crack growth (FCG) behaviors of a new burn-resistant highly-stabilized beta Ti40 alloy. The FCG rotes were analyzed. The fracture surfaces and the side surfaces of the test samples were explored. The results show that frequency affects the cracking behaviors of Ti40 alloy. Temperature also plays an important role in Ti40 alloy cracking. At room temperature (25℃), when the frequency increases, the cracking rate changes a little in the range of low stress intensity factor (ΔK), while it changes significantly when ΔK is high. At 500℃, the cracking rate of Ti40 alloy changes significantly during all the course of clacking. The frequency also affects the microstructure patterns of Ti40 alloy. A number of secondary cracks appear in the area more than 200 μm from the main crack at a high ΔK when the fre-quency is 1 Hz, but only a few secondary cracks exist when the frequency is 10 Hz. Facet image is the main image of the fracture surfaces when the frequency is 1 Hz. While, ductile striation occupies most of the area of fracture surfaces when the frequency is 10 Hz.

  17. Nanophase formation and its behavior of corrosion resistance in C+Ti dual implanted steel

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    [1]Zhang Huixing,Zhang Xiaoji,Zhou Fengsheng et al.,High current metal-ion source for ion implantation,Rev.Sci.Instrum.,1990,61(1): 574.[2]Zhang Tonghe,Ji Chengzhou,Shen Jinghua et al.,Surface modification of steel by high-dose pulse-ion implantation of titanium,tungsten,molybdenum and carbon,Nucl.Instrum.Methods,1991,B59/60: 828.[3]Zhang Tonghe,Ji Chengzhou,Shen Jinghua et al.,The influence of Ti,N and Ti+N implantation on phase change,microstructure,growth of metallic compounds and correlated effects in hardness and wear resistance in H13 steel,Nucl.Instrum.Methods,1993,B72: 409-420.[4]Zhang Tonghe,Huang Huapeng,Ji Chengzhou et al.,The formation of metallic silicides of Ti,Y,Fe,Mo and W using metal vapor vacuum arc implantation,Surf.Coat.Technol.,1994,66: 355-360.[5]Zhang Tonghe,Ji Chengzhou,Shen Jinghua et al.,Formation of intermetallic compounds with a high flux pulse molybdenum ion beam in steel and aluminum,Surf.Coat.Technol.,1992,51:455-460.[6]Zhang Tonghe,Wang Xiaoyan,Liang Hong et al.,Behavior of MEVVA metal ion implantation for surface modification of materials,Surf.Coat.Technol.,1996,83: 280-283.[7]Zhang Tonghe,Wang Xiaoyan,Liang Hong et al.,Behavior of MEVVA metal ion implantation for surface modification of materials,Surf.Coat.Technol.,1996,83: 280-283.[8]Takakashi,K.,Waki,M.I.,Chemical and electrochemical properties of ion implanted metals,Surf.Coat.Technol.,1994,65:57-63.[9]Wolf,G K.,An historical perspective of ion bombardment research for corrosion studies,Surf.Coat.Technol.,1996,83: 1-9.[10]Zhang Tonghe,Wu Yuguang,Deng Zhiwei et al.,The corrosion behavior of nanometer embedded phase in Ti implanted H13 steel,Science in China,Ser.E,1999,42(6): 623-630.[11]Zhang Tonghe,Wu Yuguang,Yi Zhongzhen et al.,Nanophase formation and its behavior of corrosion resistance in C+Mo dual implanted steel,Science in China,Ser.E,2001,4(4): 383-388.[12]Zhang Tonghe,Wu Yuguang,Deng Zhiwei et al.Properties of corrosion

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

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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.

  20. Forming-free unipolar resistive switching behavior with conical conducting filaments in LaVO4 thin films

    Science.gov (United States)

    Hu, Ling; Tang, Xianwu; Luo, Xuan; Zhang, Kejun; Jin, Linhua; Lin, Gaoting; Chen, Li; Zhu, Xuebin; Song, Wenhai; Dai, Jianmin; Sun, Yuping

    2016-04-01

    LaVO4 thin films have been deposited on Pt / Ti /SiO2 /Si substrates by pulsed laser deposition in order to explore the resistive switching (RS) behavior of the Au/LaVO4/Pt devices. It is found that the as-prepared Au/LaVO4/Pt devices stay in the low resistance state (LRS) and no electroforming process (forming-free) is needed to trigger fresh devices for the subsequent RS. Furthermore, the devices show excellent switching parameters such as a reproducible switching effect, a high resistance ratio of  ˜104 between the LRS and high resistance state (HRS), good endurance and retention characteristics, and non-overlapping switching voltages. The dominant conduction mechanisms are Ohmic conduction in the LRS and the lower voltage region of the HRS, and Poole-Frenkel emission in the higher voltage region of the HRS. The combination of temperature dependence of resistance, x-ray photoelectron spectroscopy, and model analysis suggests that the forming-free unipolar RS behavior can be explained by the formation and rupture of conical conducting filaments formed out of oxygen vacancies. These results may be important for practical application in nonvolatile resistive switching memory.

  1. Psychosocial functioning in patients with treatment-resistant depression after group cognitive behavioral therapy

    Directory of Open Access Journals (Sweden)

    Kunisato Yoshihiko

    2010-03-01

    Full Text Available Abstract Background Although patients with Treatment Resistant Depression (TRD often have impaired social functioning, few studies have investigated the effectiveness of psychosocial treatment for these patients. We examined whether adding group cognitive behavioral therapy (group-CBT to medication would improve both the depressive symptoms and the social functioning of patient with mild TRD, and whether any improvements would be maintained over one year. Methods Forty-three patients with TRD were treated with 12 weekly sessions of group-CBT. Patients were assessed with the Global Assessment of Functioning scale (GAF, the 36-item Short-Form Health Survey (SF-36, the Hamilton Rating Scale for Depression (HRSD, the Dysfunctional Attitudes Scale (DAS, and the Automatic Thought Questionnaire-Revised (ATQ-R at baseline, at the termination of treatment, and at the 12-month follow-up. Results Thirty-eight patients completed treatment; five dropped out. For the patients who completed treatment, post-treatment scores on the GAF and SF-36 were significantly higher than baseline scores. Scores on the HRSD, DAS, and ATQ-R were significantly lower after the treatment. Thus patients improved on all measurements of psychosocial functioning and mood symptoms. Twenty patients participated in the 12-month follow-up. Their improvements for psychosocial functioning, depressive symptoms, and dysfunctional cognitions were sustained at 12 months following the completion of group-CBT. Conclusions These findings suggest a positive effect that the addition of cognitive behavioural group therapy to medication on depressive symptoms and social functioning of mildly depressed patients, showing treatment resistance.

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

    Science.gov (United States)

    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.

  3. Behavioral and Reproductive Response of White Pine Weevil (Pissodes strobi to Resistant and Susceptible Sitka Spruce (Picea sitchensis

    Directory of Open Access Journals (Sweden)

    Jeanne A. Robert

    2010-08-01

    Full Text Available White pine weevil (Pissodes strobi, Peck. is a native forest insect pest in the Pacific Northwest of North America that attacks species of spruce (Picea spp. and pine (Pinus spp.. Young Sitka spruce [Picea sitchensis (Bong. Carr.] trees are particularly susceptible to weevil attack. Pockets of naturally occurring Sitka spruce resistance have been identified in high weevil hazard areas in coastal British Columbia. In this study, we characterize behavioral, physiological and reproductive responses of weevils to an extremely resistant Sitka spruce genotype (H898 in comparison to a highly susceptible genotype (Q903. The experiments relied on a large number of three-year-old clonally propagated trees and were therefore restricted to two contrasting Sitka spruce genotypes. When exposed to resistant trees, both male and female weevils were deterred during host selection and mating, females showed delayed or reduced ovary development, and successful reproduction of weevils was prevented on resistant trees.

  4. Dry wear behaviors of wear resistant composite coatings produced by laser cladding

    Institute of Scientific and Technical Information of China (English)

    Jiang Xu; Wenjin Liu; Minlin Zhong

    2004-01-01

    Using different proportional mixtures of Ni-coated MoS2, TiC and pure Ni powders, new typical wear resistant and selflubricant coatings were formed on low carbon steel by laser cladding process. The microstructures and phase composition of the composite coatings were studied by SEM and XRD. The typical microstructure of the composite coating is composed of multisulfide phases including binary element sulfide and ternary element sulfide, γ-Ni, TiC and Mo2C. Wear tests were carried out using an FALEX-6 type pin-on-disc machine. The friction coefficient and mass loss of three kinds of MoS2/TiC/Ni laser clad coatings are lower than those of quenched 45 steel, and the worn surfaces of the laser cladding coatings are very smooth. Because of high hardness combined with low friction, the laser cladding composite coating with a mixture of 70% Ni-coated MoS2, 20%TiC and 10%pure Ni powder presents better wear behaviors than the composite coating with other powder blends. The composition analysis of the worn surface of GCr15 bearing steel shows that the transferred film from the laser cladding coating to the opposite surface of GCr15beating steel contains an amount of sulfide, which can change the micro-friction mechanism and lead to a reduced friction coefficient.

  5. 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.

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    Rajalakshmi, R.; Angappane, S.

    2015-06-01

    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/TiO2/SiOx/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.

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

    Energy Technology Data Exchange (ETDEWEB)

    Rajalakshmi, R.; Angappane, S., E-mail: angappane@cnsms.res.in [Centre for Nano and Soft Matter Sciences, Jalahalli, Bangalore-560013 (India)

    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.

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

    Science.gov (United States)

    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...

  10. Spin-glass behavior in zero magnetic field using tunnel resistance

    Energy Technology Data Exchange (ETDEWEB)

    Takeuchi, Y. [Department of Applied Physics and Physico-Infomatics, Faculty of Science and Technology, Keio University, Yokohama 223-8522 (Japan)]. E-mail: takeuchi@az.appi.keio.ac.jp; Komatsu, K. [Department of Applied Physics and Physico-Infomatics, Faculty of Science and Technology, Keio University, Yokohama 223-8522 (Japan); Maki, H. [Department of Applied Physics and Physico-Infomatics, Faculty of Science and Technology, Keio University, Yokohama 223-8522 (Japan); Taniyama, T. [Materials and Structures Laboratory, Tokyo Institute of Technology, 4529 Nagatsuta, Midori, Yokohama 226-8503 (Japan); Sato, T. [Department of Applied Physics and Physico-Infomatics, Faculty of Science and Technology, Keio University, Yokohama 223-8522 (Japan)

    2007-03-15

    The measurement of spin glass in zero magnetic field is essential to investigate the intrinsic nature of spin glass. We pay attention to tunnel resistance between spin-glass layers. The temperature dependence of tunnel resistance between spin-glass layers with the structure of AgMn/Al{sub 2}O{sub 3}/AgMn was measured, and was compared with that of Al/Al{sub 2}O{sub 3}/AgMn. For the junction of AgMn/Al{sub 2}O{sub 3}/AgMn, tunnel resistance shows a peak around the spin-glass transition temperature, but no peak was observed for the junction of Al/Al{sub 2}O{sub 3}/AgMn. The results indicate that the magnetic correlation between spin-glass layers is reflected to tunnel resistance. The singularity of the tunnel resistance between spin-glass layers is discussed by the droplet theory.

  11. Bacterial group behavior and drug resistance%细菌的群体性行为与耐药

    Institute of Scientific and Technical Information of China (English)

    王辉; 杨崇广; 牛辰

    2011-01-01

    With the increasing usage of antibiotics, bacterial drug resistance has become a serious problem.Bacterial drug resistance is a complex process, involving the host, bacteria and environment, which are independent and interactive factors.For a long time, scientists considered that bacteria behave as individual. Till recently, people found that bacteria communicate with each other. We begin to realize the importance of bacterial group behavior in survival. An increasing number of studies have tended to take bacteria as a group to study the behavior of drug resistance. Now, two important aspects of bacterial group behavior, the biofilm and bacterial programmed cell death draw a lot of attention. In this paper, the research associated with drug resistance mechanisms of biofilms and bacterial programmed cell death is reviewed.%随着抗生素的广泛使用,细菌耐药已经成为一个严重的问题.细菌耐药是一个复杂的过程,涉及宿主、细菌与环境等几个既相互独立又相互作用的因素.很久以来,人们认为细菌以个体为单位进行各种活动,直到发现细菌相互之间也存在联系,才意识到细菌群体对其个体生存的重要性.目前将细菌作为一个群体来研究其耐药行为与机制的研究越来越多,特别是细菌生物膜与细菌程序性死亡两方面受到极大重视.本文综述了细菌生物膜、细菌程序性死亡与耐药相关机制的研究进展.

  12. Nonvolatile conductive filaments resistive switching behaviors in Ag/GaO{sub x} /Nb:SrTiO{sub 3}/Ag structure

    Energy Technology Data Exchange (ETDEWEB)

    Li, P.G. [Beijing University of Posts and Telecommunications, State Key Laboratory of Information Photonics and Optical Communication, Beijing (China); Zhejiang Sci-Tech University, Center for Optoelectronics Materials and Devices, Hangzhou (China); Zhi, Y.S.; An, Y.H.; Guo, D.Y.; Tang, W.H.; Xiao, J.H. [Beijing University of Posts and Telecommunications, State Key Laboratory of Information Photonics and Optical Communication, Beijing (China); Wang, P.C. [Zhejiang Sci-Tech University, Center for Optoelectronics Materials and Devices, Hangzhou (China); Sun, Z.B. [Chinese Academy of Sciences, Key Laboratory of Electronics and Information Technology for Space Systems, National Space Science Center, Beijing (China); Li, L.H. [State University of New York at Potsdam, Department of Physics, Potsdam, NY (United States)

    2016-07-15

    Ag/GaO{sub 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. (orig.)

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

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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  .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.

  15. Bottom-electrode effect on switching behavior and interface reaction in nanoionic-based resistive changing memory

    Science.gov (United States)

    Nagata, Takahiro; Yamashita, Yoshiyuki; Yoshikawa, Hideki; Imura, Masataka; Oh, Seungjun; Kobashi, Kazuyoshi; Chikyow, Toyohiro

    2016-08-01

    The bottom-electrode effect on a Cu/HfO2 stack structure, which is an oxide-based resistive random access memory (ReRAM) structure, and the resistance switching behavior of the structures were investigated by hard X-ray photoelectron spectroscopy and by comparing the Pt and TiN bottom electrodes. In the Pt bottom electrode, a forward bias voltage induced the reduction of the unintentionally oxidized Cu top electrode and the Cu ion migration in the HfO2 layer, resulting in the switching from the high resistivity to the low resistivity at approximately ±1 V. In contrast, the TiN bottom electrode induced the formation of oxygen vacancies in the HfO2 layer and the thick Cu2O layer at the Cu/HfO2 interface, namely, it induced oxygen migration rather than Cu migration. The switching voltage of the Cu/HfO2/TiN structure was twice that of the Cu/HfO2/Pt structure. The switching mechanism in a nanoionic-type ReRAM structure can be controlled by changing the bottom electrode.

  16. Improvement of Cracking-resistance and Flexural Behavior of Cement-based Materials by Addition of Rubber,Particles

    Institute of Scientific and Technical Information of China (English)

    KANG Jingfu; JIANG Yongqi

    2008-01-01

    By ring test and bend test,the improvement of waste tire rubber particles on the crack-resistance and flexural behaviors of cement-based materials were investigated.Test results show that the cracking time of the ring specimens can be retarded by the incorporation of rubber particles in the cement paste and mortar.The improvement in the crack-resistance depended on the rubber fraction.When the rubber fraction was 20%in volume,the cracking time was retarded about 15 h for the paste and 24 d for the mortar respectively.Flexural properties were evaluated based on the bend test results for both mortar and concrete containing different amount of rubber particles.Test results show that rubberized mortar and concrete specimens exhibit ductile failure and significant deformation before fracture.The ultimate deformations of both mortar and concrete specimen increase more than 2-4 times than control specimens.

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

    Science.gov (United States)

    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…

  18. Vortex Depinning in YBa2Cu3O7 : Resistive Transition Identification of the Crossover from Flux-Creep to Flux-Flow Behavior

    NARCIS (Netherlands)

    Hebard, A.F.; Palstra, T.T.M.

    1989-01-01

    Analysis of resistive transitions of YBa2Cu3O7, crystals reveals a scaling behavior which identifies the vortex-depinning critical field Hcp, hence the crossover in behavior from flux creep to flux flow. The inferred Hcp for YBa2Cu3O7 crystals closely approximates the magnitude and temperature depen

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

    Science.gov (United States)

    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.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

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

    Science.gov (United States)

    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)

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

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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

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

    OpenAIRE

    2011-01-01

    Sarah E Hetrick1, Georgina R Cox1, Sally N Merry21Orygen Youth Health Research Centre, Centre for Youth Mental Health, Melbourne, Parkville, Victoria, Australia; 2Werry Centre for Child and Adolescent Mental Health, Department of Psychological Medicine, The University of Auckland, Auckland, New ZealandBackground: Many young people with major depression fail first-line treatments. Treatment resistant depression has various definitions in the literature but typically assumes nonrespons...

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

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  10. Anomalous steam oxidation behavior of a creep resistant martensitic 9 wt. % Cr steel

    Energy Technology Data Exchange (ETDEWEB)

    Agüero, Alina, E-mail: agueroba@inta.es [Instituto Nacional de Técnica Aeroespacial, Ctra. de Ajalvir Km 4, 28850 Torrejón de Ardoz (Spain); González, Vanessa [Instituto Nacional de Técnica Aeroespacial, Ctra. de Ajalvir Km 4, 28850 Torrejón de Ardoz (Spain); Mayr, Peter [Chair of Welding Engineering, Chemnitz University of Technology, Reichenhainer Str. 70, 09126 Chemnitz (Germany); Spiradek-Hahn, Krystina [Alloy Development Group, Montanuniversität Leoben, 8700 Leoben (Austria)

    2013-08-15

    The efficiency of thermal power plants is currently limited by the long-term creep strength and the steam oxidation resistance of the commercially available ferritic/martensitic steel grades. Higher operating pressures and temperatures are essential to increase efficiency but impose important requirements on the materials, from both the mechanical and chemical stability perspective. It has been shown that in general, a Cr wt. % higher than 9 is required for acceptable oxidation rates at 650 °C, but on the other hand such high Cr content is detrimental to the creep strength. Surprisingly, preliminary studies of an experimental 9 wt. % Cr martensitic steel, exhibited very low oxidation rates under flowing steam at 650 °C for exposure times exceeding 20,000 h. A metallographic investigation at different time intervals has been carried out. Moreover, scanning transmission electron microscopy (STEM) analysis of a ground sample exposed to steam for 10,000 h at 650 °C revealed the formation of a complex tri-layered protective oxide comprising a top and bottom Fe and Cr rich spinel layer with a magnetite intermediate layer on top of a very fine grained zone. - Highlights: • High steam oxidation resistant 9 wt. % Cr martensitic steel at 650 °C. • Multilayer thin protective Cr–Fe oxide. • Nano-grain sub-oxide metal zone.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  14. Behaviorism

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  17. Anomalous behaviors in resistivity and magnetization of reduction-treated multi phase ceramics of Pr124/Pr123 and inhomogeneous Pr247

    Energy Technology Data Exchange (ETDEWEB)

    Hagiwara, M., E-mail: hag@kit.ac.j [Faculty of Engineering and Design, Kyoto Institute of Technology, Kyoto (Japan); Shima, T. [Advanced Technology Center, Kyoto Institute of Technology, Kyoto (Japan); Tanaka, S. [Faculty of Engineering and Design, Kyoto Institute of Technology, Kyoto (Japan); Koyama, K. [Faculty of Integrated Arts and Sciences, University of Tokushima, Tokushima (Japan)

    2010-12-15

    A superconductive sign found in electric resistivity behavior of mixed ceramic Pr124/Pr123 is searched and discussed, to advance preceding discussion about the superconductive region induced by intergrain charge transfer effect in ceramic Pr247 containing the related impurity phases. Observed reduction effects for largely impure ceramic of Pr247 with Pr124 and Pr123 and for simply dual-phase sample of Pr124/Pr123 inform us that the oxygen-reduction brings not only superconductive electron doping but also normal resistivity enhancement. Milder heat treatment condition is expected to assist possible attainment of zero-resistivity for Pr124/Pr123.

  18. Anomalous behavior of linear resistivity arising in intergrain ordering process of weak-sintered ceramic system YBa{sub 2}Cu{sub 4}O{sub 8}

    Energy Technology Data Exchange (ETDEWEB)

    Hagiwara, M., E-mail: hag@kit.ac.jp [Kyoto Institute of Technology, Sakyo-ku, Kyoto 606-8585 (Japan); Fujii, A.; Hayashi, T.; Shima, T. [Kyoto Institute of Technology, Sakyo-ku, Kyoto 606-8585 (Japan); Deguchi, H. [Kyushu Institute of Technology, Tobata-Ku, Kitakyusyu 804-8550 (Japan)

    2011-11-15

    Ceramic system of YBa{sub 2}Cu{sub 4}O{sub 8} (Y124) shows intergrain ordering affected by frustration. Novel vanishing process of electric resistivity is caused by the frustration effect. Almost vanished resistivity around the critical temp. is restored below the region. Faint peak of resistivity appears certainly below the ordering point decided magnetically. Faint electric resistivity behavior is searched experimentally near and below intergrain ordering temperature of weakly sintered ceramic YBa{sub 2}Cu{sub 4}O{sub 8} (Y124). For this purpose, a new method to detect linear and nonlinear resistivity sensitively by combination of pulse delta method and numerical Fourier-transformation has been designed. Making use of the experimental system for several weak sintered Y124 samples, it is revealed that linear resistivity just above the intergrain ordering point first drops toward zero steeply with decreasing temperature, and then turns abruptly upward to forms faint maximum at lower temperature. Such a novel behavior of 'revival of resistivity' is confirmed to be reproducible, and considered to be an essential frustration effect for d-wave type grain system with irregular or inhomogeneous ceramic structure.

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

    Science.gov (United States)

    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.

  20. Static recrystallization behavior of a martensitic heat-resistant stainless steel 403Nb

    Institute of Scientific and Technical Information of China (English)

    Zhouyu ZENG; Liqing CHEN; Fuxian ZHU; Xianghua LIU

    2011-01-01

    A static recrystallization behavior between the rolling passes of a martensitic heatresistant stainless steel 403Nb has been studied by OM,TEM and double-hit thermomechanical simulator to explore the effects of deformation temperature,strain rate,strain and the prior austenite grain size.The results show that increases of deformation temperature and strain rate and strain can promote the static recrystallization of 403Nb steel.Static recrystallization also proceeds faster when the prior austenite grain size is smaller.Microstructural observation indicates that the volume fraction of static recrystallization increases with prolonged interval of the rolling passes.Straininduced precipitation can lead to an appearance of a platform in the kinetic curve of static recrystallization.Different from the conventional micro-alloying steel,the strain-induced precipitates in 403Nb steel during hot rolling are carbides containing Nb and Cr.

  1. Brain structural abnormalities in behavior therapy-resistant obsessive-compulsive disorder revealed by voxel-based morphometry

    Directory of Open Access Journals (Sweden)

    Hashimoto N

    2014-10-01

    Full Text Available Nobuhiko Hashimoto,1 Shutaro Nakaaki,2 Akiko Kawaguchi,1 Junko Sato,1 Harumasa Kasai,3 Takashi Nakamae,4 Jin Narumoto,4 Jun Miyata,5 Toshi A Furukawa,6,7 Masaru Mimura2 1Department of Psychiatry and Cognitive-Behavioral Medicine, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan; 2Department of Neuropsychiatry, Keio University School of Medicine, Tokyo, Japan; 3Department of Central Radiology, Nagoya City University Hospital, Nagoya, Japan; 4Department of Psychiatry, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan; 5Department of Psychiatry, Graduate School of Medicine, Kyoto University, Kyoto, Japan; 6Department of Health Promotion and Human Behavior, 7Department of Clinical Epidemiology, Kyoto University Graduate School of Medicine/School of Public Health, Kyoto, Japan Background: Although several functional imaging studies have demonstrated that behavior therapy (BT modifies the neural circuits involved in the pathogenesis of obsessive-compulsive disorder (OCD, the structural abnormalities underlying BT-resistant OCD remain unknown. Methods: In this study, we examined the existence of regional structural abnormalities in both the gray matter and the white matter of patients with OCD at baseline using voxel-based morphometry in responders (n=24 and nonresponders (n=15 to subsequent BT. Three-dimensional T1-weighted magnetic resonance imaging was performed before the completion of 12 weeks of BT. Results: Relative to the responders, the nonresponders exhibited significantly smaller gray matter volumes in the right ventromedial prefrontal cortex, the right orbitofrontal cortex, the right precentral gyrus, and the left anterior cingulate cortex. In addition, relative to the responders, the nonresponders exhibited significantly smaller white matter volumes in the left cingulate bundle and the left superior frontal white matter. Conclusion: These results suggest that the brain

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

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

    2016-03-01

    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 (p0.05). 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.

  4. Electrical Resistance and Acoustic Emission Measurements for Monitoring the Structural Behavior of CFRP Laminate

    KAUST Repository

    Zhou, Wei

    2015-07-12

    Electrical resistance and acoustic emission (AE) measurement are jointly used to monitor the degradation in CFRP laminates subjected to tensile tests. The objective of this thesis is to perform a synergertic analysis between a passive and an active methods to better access how these perform when used for Structural Health Moni- toring (SHM). Laminates with three different stacking sequences: [0]4, [02/902]s and [+45/ − 45]2s are subjected to monotonic and cyclic tensile tests. In each laminate, we carefully investigate which mechanisms of degradation can or cannot be detect- ed by each technique. It is shown that most often, that acoustic emission signals start before any electrical detection is possible. This is is explained based on the redundance of the electrical network that makes it less sensitive to localized damages. Based on in depth study of AE signals clustering, a new classification is proposed to recognize the different damage mechanims based on only two parameters: the RA (rise time/amplitude) and the duration of the signal.

  5. Oxidation behavior of nuclear graphite and the improvement of corrosion resistance and thermal shock resistance of graphite materials by compositionally graded SiC coating

    Energy Technology Data Exchange (ETDEWEB)

    Fujii, Kimio [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1999-08-01

    relation between corrosion behavior and the total surface area in the case of air oxidation in the chemical reaction control and in-pore diffusion control regimes. (3) Taking advantage of the information obtained in (1) and (2) above, the corrosion resistance, a disadvantage of graphite materials, was improved by introducing a compositionally gradient SiC/C material using the reaction between silicon monoxide and carbon. (author)

  6. Low-Cost Avoidance Behaviors Are Resistant To Fear Extinction In Humans

    Directory of Open Access Journals (Sweden)

    Bram eVervliet

    2015-12-01

    Full Text Available Elevated levels of fear and avoidance are core symptoms across the anxiety disorders. It has long been known that fear serves to motivate avoidance. Consequently, fear extinction has been the primary focus in pre-clinical anxiety research for decades, under the implicit assumption that removing the motivator of avoidance (fear would automatically mitigate the avoidance behaviors as well. Although this assumption has intuitive appeal, it has received little scientific scrutiny. The scarce evidence from animal studies is mixed, while the assumption remains untested in humans. The current study applied an avoidance conditioning protocol in humans to investigate the effects of fear extinction on the persistence of low-cost avoidance. Online danger-safety ratings and skin conductance responses documented the dynamics of conditioned fear across avoidance and extinction phases. Anxiety- and avoidance-related questionnaires explored individual differences in rates of avoidance. Participants first learned to click a button during a predictive danger signal, in order to cancel an upcoming aversive electrical shock (avoidance conditioning. Next, fear extinction was induced by presenting the signal in the absence of shocks while button-clicks were prevented (by removing the button in Experiment 1, or by instructing not to click the button in Experiment 2. Most importantly, post-extinction availaibility of the button caused a significant return of avoidant button-clicks. In addition, trait-anxiety levels correlated positively with rates of avoidance during a predictive safety signal, and with the rate of pre- to post-extinction decrease during this signal. Fear measures gradually decreased during avoidance conditioning, as participants learned that button-clicks effectively canceled the shock. Preventing button-clicks elicited a sharp increase in fear, which subsequently extinguished. Fear remained low during avoidance testing, but danger-safety ratings

  7. Low-Cost Avoidance Behaviors are Resistant to Fear Extinction in Humans.

    Science.gov (United States)

    Vervliet, Bram; Indekeu, Ellen

    2015-01-01

    Elevated levels of fear and avoidance are core symptoms across the anxiety disorders. It has long been known that fear serves to motivate avoidance. Consequently, fear extinction has been the primary focus in pre-clinical anxiety research for decades, under the implicit assumption that removing the motivator of avoidance (fear) would automatically mitigate the avoidance behaviors as well. Although this assumption has intuitive appeal, it has received little scientific scrutiny. The scarce evidence from animal studies is mixed, while the assumption remains untested in humans. The current study applied an avoidance conditioning protocol in humans to investigate the effects of fear extinction on the persistence of low-cost avoidance. Online danger-safety ratings and skin conductance responses documented the dynamics of conditioned fear across avoidance and extinction phases. Anxiety- and avoidance-related questionnaires explored individual differences in rates of avoidance. Participants first learned to click a button during a predictive danger signal, in order to cancel an upcoming aversive electrical shock (avoidance conditioning). Next, fear extinction was induced by presenting the signal in the absence of shocks while button-clicks were prevented (by removing the button in Experiment 1, or by instructing not to click the button in Experiment 2). Most importantly, post-extinction availability of the button caused a significant return of avoidant button-clicks. In addition, trait-anxiety levels correlated positively with rates of avoidance during a predictive safety signal, and with the rate of pre- to post-extinction decrease during this signal. Fear measures gradually decreased during avoidance conditioning, as participants learned that button-clicks effectively canceled the shock. Preventing button-clicks elicited a sharp increase in fear, which subsequently extinguished. Fear remained low during avoidance testing, but danger-safety ratings increased again when

  8. Caesalpinia echinata Lam. - BRAZILWOOD: THERMAL BEHAVIOR, STRUCTURAL CHARACTERISTICS, AND RESISTANCE TO BIODETERIORATION IN STATIC SYSTEMS

    Directory of Open Access Journals (Sweden)

    Ana Paula Pinto Pinheiro

    Full Text Available ABSTRACT Wood is the best-known biological material used as a raw material since the dawn of mankind until present days. As a natural and renewable composite, its lifetime is limited by the degradation of its basic elements. This degradation can be caused by chemical reactions or by biological agents capable of accelerating the process of deterioration. In this work, the wear, thermal, and micro-structural characteristics, as also the bio-degradation behavior in static systems, of the wood species Brazilwood (Caesalpinia echinata were studied under laboratory conditions in order to use these woods in design. The results show that Brazilwood has a good visual performance after abrasion test, since it has not shown any representative roughness increase. In addition, Brazilwood has high level of crystallinity of, approximately, 68% and was almost insensitive to fungi attack, forming only 5.3 x 103 CFU/mL. Besides, its texture did not change due to exposure to water or sweat.

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

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Yao-Feng, E-mail: yfchang@utexas.edu; Zhou, Fei; Chen, Ying-Chen; Lee, Jack C. [Microelectronics Research Center, Department of Electrical and Computer Engineering, The University of Texas at Austin, Austin, Texas 78758 (United States); Fowler, Burt [PrivaTran, LLC, 1250 Capital of Texas Highway South, Bldg 3, Ste 400, Austin, Texas 78746 (United States)

    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.

  10. 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

    Directory of Open Access Journals (Sweden)

    Karunamuni Nandini

    2008-12-01

    Full Text Available Abstract Background 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. Objective 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. Methods 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. Results 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. Conclusion These results may guide the development of appropriate PA interventions for aerobic PA and resistance training based on the TPB.

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

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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.

  13. Influence of Oxidation Behavior of Feedstock on Microstructure and Ablation Resistance of Plasma-Sprayed Zirconium Carbide Coating

    Science.gov (United States)

    Hu, Cui; Ge, Xuelian; Niu, Yaran; Li, Hong; Huang, Liping; Zheng, Xuebin; Sun, Jinliang

    2015-10-01

    Plasma spray is one of the suitable technologies to deposit carbide coatings with high melting point, such as ZrC. However, in the spray processes performed under atmosphere, oxidation of the carbide powder is inevitable. To investigate the influence of the oxidation behavior of feedstock on microstructure and ablation resistance of the deposited coating, ZrC coatings were prepared by atmospheric and vacuum plasma spray (APS and VPS) technologies, respectively. SiC-coated graphite was applied as the substrate. The obtained results showed that the oxidation of ZrC powder in APS process resulted in the formation of ZrO and Zr2O phases. Pores and cracks were more likely to be formed in the as-sprayed APS-ZrC coating. The VPS-ZrC coating without oxides possessed denser microstructure, higher thermal diffusivity, and lower coefficients of thermal expansion as compared with the APS-ZrC coating. A dense ZrO2 layer would be formed on the surface of the VPS-ZrC-coated sample during the ablation process and the substrate can be protected sufficiently after being ablated in high temperature plasma jet. However, the ZrO2 layer, formed by oxidation of the APS-ZrC coating having loose structure, was easy to be washed away by the shearing action of the plasma jet.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  16. Microstructure and Resisting Thermal Shock Behaviors of TiC-Al2O3/Fe Functionally Graded MaterialsPrepared by SHS/PHIP

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The microstructure and composition of TiC-Al2O3/Fe functionally graded materials (FGM) prepared by self-propagating high temperature synthesis and pseudo-hot isostatic pressing (SHS/PHIP) were studied, and the resisting thermal shock behaviors were analyzed. The results show that TiC-Al2O3/Fe FGM has graded composition distribution. No cross-section crack through the layers was found in the tests of thermal shock and fatigue.

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

    Science.gov (United States)

    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.

  18. Investigation of edge- and bulk-related resistive switching behaviors and backward-scan effects in SiOx-based resistive switching memory

    Science.gov (United States)

    Chang, Yao-Feng; Ji, Li; Wang, Yanzhen; Chen, Pai-Yu; Zhou, Fei; Xue, Fei; Fowler, Burt; Yu, Edward T.; Lee, Jack C.

    2013-11-01

    Switching characteristics of edge and bulk device structures and an unusual backward-scan effect are investigated in SiOx-based resistive memory. Adding external resistance is found to dramatically affect reset voltage, providing insight into the unique unipolar operation. Non-edge, bulk SiOx-based devices allow flexibility in the fabrication process and hydrogen incorporation improves electroforming and device yield. A backward-scan phenomenon is examined by investigating the DC and AC pulse responses, which defines requirements for ON and OFF programming duration. Circuit-level simulation using a Verilog-A model aids device characterization and programming strategy development for future nonvolatile memory applications.

  19. Study of the fire resistant behavior of unfilled and carbon nanofibers reinforced polybenzimidazole coating for structural applications

    NARCIS (Netherlands)

    Iqbal, H.M.S.; Stec, A.A.; Patel, P.; Bhowmik, S.; Benedictus, R.

    2013-01-01

    With increasing interest in epoxy-based carbon fiber composites for structural applications, it is important to improve the fire resistant properties of these materials. The fire resistant performance of these materials can be improved either by using high performance epoxy resin for manufacturing c

  20. Distinct behavioral phenotypes in novel "fast" kindling-susceptible and "slow" kindling-resistant rat strains selected by stimulation of the hippocampal perforant path.

    Science.gov (United States)

    Langberg, Tomer; Dashek, Ryan; Mulvey, Bernard; Miller, Kimberly A; Osting, Susan; Stafstrom, Carl E; Sutula, Thomas P

    2016-01-01

    Kindling is a phenomenon of activity-dependent neural circuit plasticity induced by repeated seizures that results in progressive permanent increases in susceptibility to epilepsy. As the permanent structural and functional modifications induced by kindling include a diverse range of molecular, cellular, and functional alterations in neural circuits, it is of interest to determine if genetic background associated with seizure-induced plasticity might also influence plasticity in neural circuitry underlying other behaviors. Outbred Sprague-Dawley (SD) rats were selected and bred for ~15 generations for "fast' or "slow" rates of kindling development in response to stimulation of the perforant path input to the hippocampus. After 7-8 generations of selection and breeding, consistent phenotypes of "fast" and "slow" kindling rates were observed. By the 15th generation "fast" kindling rats referred to as Perforant Path Kindling Susceptible (PPKS) rats demonstrated a kindling rate of 10.7 ± 1.1 afterdischarges (ADs) to the milestone of the first secondary generalized (Class V) seizure, which differed significantly from "slow" kindling Perforant Path Kindling Resistant (PPKR) rats requiring 25.5 ± 2.0 ADs, and outbred SD rats requiring 16.8 ± 2.5 ADs (pkindling) strain with increased susceptibility to seizure-induced plasticity demonstrated statistically significant increases in motor exploratory activity in the open field test and reduced spatial learning the Morris water maze, but demonstrated normal fear conditioned learning comparable to outbred SD rats and the "slow" kindling-resistant PPKR strain. These results confirm that selection and breeding on the basis of responses to repeated pathway activation by stimulation can produce enduring modification of genetic background influencing behavior. These observations also suggest that genetic background underlying susceptibility or resistance to seizure-induced plasticity in hippocampal circuitry also differentially

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

    Science.gov (United States)

    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

  2. 矩形铁氧体衬底抗蚀剂的旋涂特性%Spin-coating behavior of resist for rectangular ferrite substrate

    Institute of Scientific and Technical Information of China (English)

    倪经; 魏恭; 陈彦; 周俊; 谭士杰

    2013-01-01

      采用半导体工艺的旋转涂胶法,在矩形铁氧体衬底上旋涂抗蚀剂,研究了其涂覆特性,给出了抗蚀剂的厚度与旋涂转速和旋涂时间的关系曲线及均匀性。随着旋涂转速的提高,抗蚀剂的厚度逐渐减薄;当旋涂转速大于2500r/min 时,抗蚀剂厚度差小于5%。同时,随着旋涂时间的延长,抗蚀剂厚度也会减小,并最终趋向一个恒定值;当旋涂时间长于20s 时,抗蚀剂厚度差小于5%。最后,分析了旋涂中心对抗蚀剂旋涂性能的影响。%  Abstrate: Resist was coated on the rectangular ferrite substrate by spin-coating route of semiconductor technology, and the relation were investigated between thickness and uniformity of resist and the spin-coating speed and time. The thickness of resist gradually decreases with increasing spin-coating speed. For spin-coating speed of faster than 2500 r/min, the thickness difference of resist is within 5%. Meanwhile, the thickness of resist decreases with prolonging spin-coating time and finally tends to reach a constant value. The thickness difference of resist is within 5%as the spin-coating time is over 20s. At last, the effect of spin-coating center was analyzed on the spin-coating behavior.

  3. 矩形铁氧体衬底抗蚀剂的旋涂特性%Spin-coating behavior of resist for rectangular ferrite substrate

    Institute of Scientific and Technical Information of China (English)

    倪经; 魏恭; 陈彦; 周俊; 谭士杰

    2012-01-01

    Resist was coated on the rectangular ferrite substrate by spin-coating route of semiconductor technology, and the relation were investigated between thickness and uniformity of resist and the spin-coating speed and time. The thickness of resist gradually decreases with increasing spin-coating speed. For spin-coating speed of faster than 2500 r/min, the thickness difference of resist is within 5%. Meanwhile, the thickness of resist decreases with prolonging spin-coating time and finally tends to reach a constant value. The thickness difference of resist is within 5% as the spin-coating time is over 20s. At last, the effect of spin-coating center was analyzed on the spin-coating behavior.%采用半导体工艺的旋转涂胶法,在矩形铁氧体衬底上旋涂抗蚀剂,研究了其涂覆特性,给出了抗蚀剂的厚度与旋涂转速和旋涂时间的关系曲线及均匀性.随着旋涂转速的提高,抗蚀剂的厚度逐渐减薄;当旋涂转速大于2500r/min时,抗蚀剂厚度差小于5%.同时,随着旋涂时间的延长,抗蚀剂厚度也会减小,并最终趋向一个恒定值;当旋涂时间长于20s时.抗蚀剂厚度差小于5%.最后,分析了旋涂中心对抗蚀剂旋涂性能的影响.

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

    Science.gov (United States)

    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.

  5. Controlling the Melt Resistance to Flow as a Possibility of Improving the Miscibility and the Time Behavior of Some Blends Based on Starch

    Directory of Open Access Journals (Sweden)

    Doina Dimonie

    2015-01-01

    Full Text Available The paper proves that the miscibility of some blends based on starch can be improved by finding for each of them the melt resistance to flow at which the nonstationary flow and the melt degradation are avoided and the developed shear rate homogenizes optimally the material composition. The obtained results show that, for process sensitive materials like starches, the border between good and less miscibility is so narrow that the window of melt processing conditions and the best formulation must be found for each of them. The improving of miscibility by controlling the melt resistance to flow proves to be a good method to prevent retrogradation and plasticizer leaching and so to handle the new compounds behavior during usage.

  6. Development of Triticum aestivum-Leymus racemosus ditelosomic substitution line 7Lr#1S(7A) with resistance to wheat scab and its meiotic behavior analysis

    Institute of Scientific and Technical Information of China (English)

    WANG LinSheng; CHEN PeiDu

    2008-01-01

    Leymus racemosus is highly resistant to wheat scab (Fusarum head bright). The transfer of scab re-sistant gene from L. racemosus to Triticum aestivum is of great significance for broadening the base of wheat resistance. In the present study, the pollen of T. aestivum-L, racemosus monosomic addition linewith scab resistance was treated by irradiation with 1200 R 60Co-γ-rays prior to pollinating to emasculated wheat cv. Mianyang 85-45. Nine plants with a telocentric chromosome 7Lr#1S were observed in M1,and one ditelosomic substitution line 7Lr#1S was selected from selfcrossing progenies and confirmed by chromosome C-banding and GISH. Furthermore, a co-dominant EST-SSR marker CINAU 31 was em-ployed to identify this substitution line. A pair of chromosome 7A of common wheat were found to be replaced by a pair of telocentric chromosome 7Lr#1S, and further investigation showed that chromo-some configuration of the substitution line at MI of PMCs after GISH was 17.50(Ⅱ) w + 2.19 (Ⅱ)w +0.42 (Ⅱ)7Lr#1S + 1.08 Ⅰ7Lr#1S + 0.69 Ⅰw. Two telocentric chromosomes paired as a bivalent in 59.7% of PMCs.Abnormal chromosome behaviors of telocentric chromosomes were observed in part of PMCs at ana-phase Ⅰ and telophase Ⅰ, including the moving of two telocentric chromosomes to the same pole, lag-ging and earlier separation of their sister chromatid. All these abnormal behaviors can be grouped into three distinct types of tetrads according to different numbers of 7Lr#1S in their daughter cells and various micronucieus in some tetrads. However, due to the high transmission frequency of the female and male gametes with a 7Lr#1S, 84% of the selfcrossing progeny plants had ditelosomic substitution. The substitution line showed high resistance to wheat scab in a successive two-year test both in the greenhouse and field; hence, the line will be particularly valuable for alien gene mapping, small frag-ment translocation induction and telosomic cytological behavior analysis.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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...

  9. Rectifying characteristics and bipolar resistance switching behaviors in sol-gel processed TiOx thin film

    Science.gov (United States)

    Kim, Jang-Han; Nam, Ki-Hyun; Cho, Won-Ju; Chung, Hong-Bay

    2015-04-01

    We demonstrate a sol-gel processed Ti/TiOx/Pt device for rectifying characteristics as well as resistive switching. In the rectification mode, Ti/TiOx/Pt device exhibited a forward current density (>102 A/cm2) and on/off ratio (>104) owing to asymmetric Schottky barrier at the Ti/TiOx (0.11 eV) and TiOx/Pt (0.57 eV). After the forming process by applying the positive bias, the rectification mode of sol-gel TiOx device changed to the resistive switching mode. In the case of resistive switching mode, when applying the negative bias, the high resistance state (HRS) is dominated by Schottky emission in low voltage and by Poole-Frenkel emission in high voltage. Contrary to applying the negative bias, the HRS exhibited the Schottky emission in the whole positive bias. Different type of switching mechanisms might be attributed to the oxygen vacancy distribution across the TiOx active layer.

  10. Effect of deep cryogenic treatment and tempering on microstructure and mechanical behaviors of a wear-resistant austempered alloyed bainitic ductile iron

    Directory of Open Access Journals (Sweden)

    Chen Liqing

    2015-01-01

    Full Text Available In this paper, the effect of deep cryogenic treatment in combination with conven- tional heat treatment process was investigated on microstructure and mechanical behaviors of alloyed bainitic ductile iron. Three processing schedules were employed to treat this alloyed ductile iron including direct tempering treatment, tempering.+deep cryogenic treatment and deep cryogenic treatment.+tempering treatments. The microstructure and mechanical behavior, especially the wear resistance, have been evaluated after treated by these three schedules. The results show that martensite microstructure can be obviously refined and the precipitation of dispersed carbides is promoted by deep cryogenic treatment at .−196 ∘C for 3 h after tempered at 450 ∘C for 2 h. In this case, the alloyed bainitic ductile iron possesses rather high hardness and wear-resistance than those processed by other two schedules. The main wear mechanism of the austempered alloyed ductile iron with deep cryogenic treatment and tempering is micro-cutting wear in association with plastic deformation wear.

  11. 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.

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  14. 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.

    Science.gov (United States)

    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.

  15. The HDAC inhibitor SAHA improves depressive-like behavior of CRTC1-deficient mice: possible relevance for treatment-resistant depression

    KAUST Repository

    Meylan, Elsa M.

    2016-03-09

    Major depression is a highly complex disabling psychiatric disorder affecting millions of people worldwide. Despite the availability of several classes of antidepressants, a substantial percentage of patients are unresponsive to these medications. A better understanding of the neurobiology of depression and the mechanisms underlying antidepressant response is thus critically needed. We previously reported that mice lacking CREB-regulated transcription coactivator 1 (CRTC1) exhibit a depressive-like phenotype and a blunted antidepressant response to the selective serotonin reuptake inhibitor fluoxetine. In this study, we similarly show that Crtc1‒/‒ mice are resistant to the antidepressant effect of chronic desipramine in a behavioral despair paradigm. Supporting the blunted response to this tricyclic antidepressant, we found that desipramine does not significantly increase the expression of Bdnf and Nr4a1-3 in the hippocampus and prefrontal cortex of Crtc1‒/‒ mice. Epigenetic regulation of neuroplasticity gene expression has been associated with depression and antidepressant response, and histone deacetylase (HDAC) inhibitors have been shown to have antidepressant-like properties. Here, we show that unlike conventional antidepressants, chronic systemic administration of the HDAC inhibitor SAHA partially rescues the depressive-like behavior of Crtc1‒/‒ mice. This behavioral effect is accompanied by an increased expression of Bdnf, but not Nr4a1-3, in the prefrontal cortex of these mice, suggesting that this epigenetic intervention restores the expression of a subset of genes by acting downstream of CRTC1. These findings suggest that CRTC1 alterations may be associated with treatment-resistant depression, and support the interesting possibility that targeting HDACs may be a useful therapeutic strategy in antidepressant development.

  16. Environmental enrichment induces behavioral recovery and enhanced hippocampal cell proliferation in an antidepressant-resistant animal model for PTSD.

    Directory of Open Access Journals (Sweden)

    Hendrikus Hendriksen

    Full Text Available BACKGROUND: Post traumatic stress disorder (PTSD can be considered the result of a failure to recover after a traumatic experience. Here we studied possible protective and therapeutic aspects of environmental enrichment (with and without a running wheel in Sprague Dawley rats exposed to an inescapable foot shock procedure (IFS. METHODOLOGY/PRINCIPAL FINDINGS: IFS induced long-lasting contextual and non-contextual anxiety, modeling some aspects of PTSD. Even 10 weeks after IFS the rats showed reduced locomotion in an open field. The antidepressants imipramine and escitalopram did not improve anxiogenic behavior following IFS. Also the histone deacetylase (HDAC inhibitor sodium butyrate did not alleviate the IFS induced immobility. While environmental enrichment (EE starting two weeks before IFS did not protect the animals from the behavioral effects of the shocks, exposure to EE either immediately after the shock or one week later induced complete recovery three weeks after IFS. In the next set of experiments a running wheel was added to the EE to enable voluntary exercise (EE/VE. This also led to reduced anxiety. Importantly, this behavioral recovery was not due to a loss of memory for the traumatic experience. The behavioral recovery correlated with an increase in cell proliferation in hippocampus, a decrease in the tissue levels of noradrenalin and increased turnover of 5-HT in prefrontal cortex and hippocampus. CONCLUSIONS/SIGNIFICANCE: This animal study shows the importance of (physical exercise in the treatment of psychiatric diseases, including post-traumatic stress disorder and points out the possible role of EE in studying the mechanism of recovery from anxiety disorders.

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

    Science.gov (United States)

    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.

  18. Fermi liquid behavior of the in-plane resistivity in the pseudogap state of YBa2Cu4O8

    Science.gov (United States)

    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.

  19. RKIP inhibition in cervical cancer is associated with higher tumor aggressive behavior and resistance to cisplatin therapy.

    Directory of Open Access Journals (Sweden)

    Olga Martinho

    Full Text Available Cervical cancer is one of the most common cancers in women worldwide, being high-risk group the HPV infected, the leading etiological factor. The raf kinase inhibitory protein (RKIP has been associated with tumor progression and metastasis in several human neoplasms, however its role on cervical cancer is unclear. In the present study, 259 uterine cervix tissues, including cervicitis, cervical intraepithelial lesions and carcinomas, were analyzed for RKIP expression by immunohistochemistry. We found that RKIP expression was significantly decreased during malignant progression, being highly expressed in non-neoplastic tissues (54% of the samples; 73/135, and expressed at low levels in the cervix invasive carcinomas (∼15% (19/124. Following in vitro downregulation of RKIP, we observed a viability and proliferative advantage of RKIP-inhibited cells over time, which was associated with an altered cell cycle distribution and higher colony number in a colony formation assay. An in vitro wound healing assay showed that RKIP abrogation is associated with increased migratory capability. RKIP downregulation was also associated with an increased vascularization of the tumors in vivo using a CAM assay. Furthermore, RKIP inhibition induced cervical cancer cells apoptotic resistance to cisplatin treatment. In conclusion, we described that RKIP protein is significantly depleted during the malignant progression of cervical tumors. Despite the lack of association with patient clinical outcome, we demonstrate, in vitro and in vivo, that loss of RKIP expression can be one of the factors that are behind the aggressiveness, malignant progression and chemotherapy resistance of cervical cancer.

  20. Effects of N/C Ratio on Solidification Behaviors of Novel Nb-Bearing Austenitic Heat-Resistant Cast Steels for Exhaust Components of Gasoline Engines

    Science.gov (United States)

    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.

  1. Effects of N/C Ratio on Solidification Behaviors of Novel Nb-Bearing Austenitic Heat-Resistant Cast Steels for Exhaust Components of Gasoline Engines

    Science.gov (United States)

    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.

  2. Evaluation of damage accumulation behavior and strength anisotropy of NITE SiC/SiC composites by acoustic emission, digital image correlation and electrical resistivity monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Nozawa, Takashi, E-mail: nozawa.takashi67@jaea.go.jp [Japan Atomic Energy Agency, Rokkasho, Aomori (Japan); Ozawa, Kazumi [Japan Atomic Energy Agency, Rokkasho, Aomori (Japan); Asakura, Yuuki; Kohyama, Akira [Muroran Institute of Technology, Muroran, Hokkaido (Japan); Tanigawa, Hiroyasu [Japan Atomic Energy Agency, Rokkasho, Aomori (Japan)

    2014-12-15

    Understanding the cracking process of the composites is essential to establish the design basis for practical applications. This study aims to investigate the damage accumulation process and its anisotropy for nano-infiltration transient eutectic sintered (NITE) SiC/SiC composites by various characterization techniques such as the acoustic emission (AE), digital image correlation (DIC) and electrical resistivity (ER) measurements. Cracking behavior below the proportional limit stress (PLS) was specifically addressed. Similar to the other generic SiC/SiC composites, the 1st AE event was identified below the PLS for NITE SiC/SiC composites with a dependency of fabric orientation. The DIC results support that the primary failure mode depending on fiber orientation affected more than the other minor modes did. Detailed AE waveform analysis by wavelet shows a potential to classify the failure behavior depending on architecture. Cracking below the PLS is a potential concern in component deign but the preliminary ER measurements imply that the impact of cracking below the PLS on composite function was limited.

  3. Crack initiation behavior of notched specimens on heat resistant steel under service type loading at high temperature

    Directory of Open Access Journals (Sweden)

    Lu Cui

    2016-10-01

    Full Text Available Cracks at notches deserve special consideration in the design of steam turbine components. This work is addressed to investigate the crack initiation behavior a 10%Cr rotor steel with the help of notched specimens under service-type loading. A significant drifting down of the peak-values of axial deformation under constant amplitude load was observed. Crack initiation was evaluated with the help of the relationship between irreversible deformation energy and cycle number. Further, metallographic examinations were employed to characterize the superposition of creep and fatigue damage mechanisms. Both Neuber-hypothesis and von Mises equivalent strain at notch root were applied for lifetime prediction. Finally, the effectiveness of both methods is validated by comparing with experimental results

  4. Unusual behavior in the reactivity of 5-substituted-1H-tetrazoles in a resistively heated microreactor.

    Science.gov (United States)

    Gutmann, Bernhard; Glasnov, Toma N; Razzaq, Tahseen; Goessler, Walter; Roberge, Dominique M; Kappe, C Oliver

    2011-01-01

    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.

  5. Unusual behavior in the reactivity of 5-substituted-1H-tetrazoles in a resistively heated microreactor

    Directory of Open Access Journals (Sweden)

    Dominique M. Roberge

    2011-04-01

    Full Text Available 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.

  6. Precipitation behavior and martensite lath coarsening during tempering of T/P92 ferritic heat-resistant steel

    Institute of Scientific and Technical Information of China (English)

    Lin-qing Xu; Dan-tian Zhang; Yong-chang Liu; Bao-qun Ning; Zhi-xia Qiao; Ze-sheng Yan; Hui-jun Li

    2014-01-01

    Tempering is an important process for T/P92 ferritic heat-resistant steel from the viewpoint of microstructure control, as it facili-tates 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 mi-croscopy. The chemical composition of the precipitates was analyzed using energy dispersive X-ray spectroscopy. Results indicate the for-mation 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.

  7. Wear-resistant and electromagnetic absorbing behaviors of oleic acid post-modified ferrite-filled epoxy resin composite coating

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Wenjie; Zang, Chongguang, E-mail: zangchongguang@bit.edu.cn; Jiao, Qingjie

    2015-03-15

    The post-modified Mn–Zn ferrite was prepared by grafting oleic acid on the surface of Mn–Zn ferrite to inhibit magnetic nanoparticle aggregation. Fourier Transform Infrared (FT-IR) spectroscopy was used to characterize the particle surfaces. The friction and electromagnetic absorbing properties of a thin coating fabricated by dispersing ferrite into epoxy resin (EP) were investigated. The roughness of the coating and water contact angle were measured using the VEECO and water contact angle meter. Friction tests were conducted using a stainless-steel bearing ball and a Rockwell diamond tip, respectively. The complex permittivity and complex permeability of the composite coating were studied in the low frequency (10 MHz–1.5 GHz). Surface modified ferrites are found to improve magnetic particles dispersion in EP resulting in significant compatibility between inorganic and organic materials. Results also indicate that modified ferrite/EP coatings have a lower roughness average value and higher water contact angle than original ferrite/EP coatings. The enhanced tribological properties of the modified ferrite/EP coatings can be seen from the increased coefficient value. The composite coatings with modified ferrite are observed to exhibit better reflection loss compared with the coatings with original ferrite. - Highlights: • The post-modified Mn-Zn ferrite was prepared by grafting oleic acid on its surface to inhibit aggregation. • The increasing in hydrophobicity and dispersion of modified coating improved compatibility between illers and polymer. • The modified fillers can decrease the friction COF of the composite coatings resulting in the enhanced resistance to wear. • The modified ferrite coatings are observed to exhibit better reflection loss compared with coatings with original ferrite.

  8. Seeking behavior, place conditioning, and resistance to conditioned suppression of feeding in rats intermittently exposed to palatable food.

    Science.gov (United States)

    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.

  9. Growth Kinetics of Laves Phase and Its Effect on Creep Rupture Behavior in 9Cr Heat Resistant Steel

    Institute of Scientific and Technical Information of China (English)

    Zhi-xin XIA; Chuan-yang WANG; Chen LEI; Yun-ting LAI; Yan-fen ZHAO; Lu ZHANG

    2016-01-01

    The effects of Laves phase formation and growth on creep rupture behaviors of P92 steel at 883 K were studied.The microstructural evolution was characterized using scanning electron microscopy and transmission elec-tron microscopy.Kinetic modeling was carried out using the software DICTRA.The results indicated Fe2 (W,Mo) Laves phase has formed during creep with 200 MPa applied stress at 883 K for 243 h.The experimental results showed a good agreement with thermodynamic calculations.The plastic deformation of laths is the main reason of creep rupture under the applied stress beyond 160 MPa,whereas,creep voids initiated by coarser Laves phase play an effective role in creep rupture under the applied stress lower than 160 MPa.Laves phase particles with the mean size of 243 nm lead to the change of creep rupture feature.Microstructures at the vicinity of fracture surface,the gage portion and the threaded ends of creep rupture specimens were also observed,indicating that creep tensile stress enhances the coarsening of Laves phase.

  10. 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

    NARCIS (Netherlands)

    Guidotti, Stefano; Meyer, Neele; Przybyt, Ewa; Scheurink, Anton J.W.; Harmsen, Martin C.; Garland Jr., Theodore; van Dijk, Gertjan

    2016-01-01

    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 inve

  11. Effects of two-step homogenization on precipitation behavior of Al{sub 3}Zr dispersoids and recrystallization resistance in 7150 aluminum alloy

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Zhanying [Department of Applied Science, University of Québec at Chicoutimi, Saguenay, QC G7H 2B1 (Canada); Key Laboratory for Anisotropy and Texture of Materials, Northeastern University, Shenyang 110819, China, (China); Zhao, Gang [Key Laboratory for Anisotropy and Texture of Materials, Northeastern University, Shenyang 110819, China, (China); Chen, X.-Grant, E-mail: xgrant_chen@uqac.ca [Department of Applied Science, University of Québec at Chicoutimi, Saguenay, QC G7H 2B1 (Canada)

    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.

  12. 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.

    Science.gov (United States)

    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.

  13. Alterations in ethanol-induced behaviors and consumption in knock-in mice expressing ethanol-resistant NMDA receptors.

    Directory of Open Access Journals (Sweden)

    Carolina R den Hartog

    Full Text Available 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; i.p. 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.

  14. Resistance, capacitance, and electrode kinetic effects in Fourier-transformed large-amplitude sinusoidal voltammetry: emergence of powerful and intuitively obvious tools for recognition of patterns of behavior.

    Science.gov (United States)

    Sher, Anna A; Bond, Alan M; Gavaghan, David J; Harriman, Kathryn; Feldberg, Stephen W; Duffy, Noel W; Guo, Si-Xuan; Zhang, Jie

    2004-11-01

    Large-amplitude sinusoidal ac voltammetric techniques, when analyzed in the frequency domain using the Fourier transform-inverse Fourier transform sequence, produce the expected dc and fundamental harmonic ac responses in addition to very substantial second, third, and higher ac harmonics that arise from the presence of significant nonlinearity. A full numerical simulation of the process, Red right arrow over left arrow Ox + e(-), incorporates terms for the uncompensated resistance (R(u)), capacitance of the double layer (C(dl)), and slow electron transfer kinetics (in particular, the reversible potential (E degrees ), rate constant (k(0)), and charge transfer coefficient (alpha) from the Butler-Volmer model). Identification of intuitively obvious patterns of behavior (with characteristically different sensitivity regimes) in dc, fundamental, and higher harmonic terms enables simple protocols to be developed to estimate R(u), C(dl), E degrees , k(0), and alpha. Thus, if large-amplitude sinusoidal cyclic voltammograms are obtained for two concentrations of the reduced species, data obtained from analysis of the recovered signals provide initial estimates of parameters as follows: (a) the dc cyclic component provides an estimate of E degrees (because the R(u) and k(0) effects are minimized); (b) the fundamental harmonic provides an estimate of C(dl) (because it has a high capacitance-to-faradaic current ratio); and (c) the second harmonic provides an estimate of R(u), k(0), and alpha (because the C(dl) effect is minimized). Methods of refining the initial estimates are then implemented. As a check on the fidelity of the parameters (estimated on the basis of an essentially heuristic approach that solely utilizes the dc, fundamental, and second harmonic voltammograms), comparison of the predicted simulated and experimental third (or higher) harmonic voltammograms can be made to verify that agreement between theory and experiment has been achieved at a predetermined

  15. Resistance to the development of stress-induced behavioral despair in the forced swim test associated with elevated hippocampal Bcl-xl expression.

    Science.gov (United States)

    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.

  16. Temperature dependent behavior of thermal conductivity of sub-5 nm Ir film: Defect-electron scattering quantified by residual thermal resistivity

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, Zhe; Xu, Zaoli; Xu, Shen [Department of Mechanical Engineering, Iowa State University, 2010 Black Engineering Building, Ames, Iowa 50011 (United States); Wang, Xinwei, E-mail: xwang3@iastate.edu [Department of Mechanical Engineering, Iowa State University, 2010 Black Engineering Building, Ames, Iowa 50011 (United States); School of Urban Development and Environmental Engineering, Shanghai Second Polytechnic University, Shanghai 201209 (China)

    2015-01-14

    By studying the temperature-dependent behavior (300 K down to 43 K) of electron thermal conductivity (κ) in a 3.2 nm-thin Ir film, we quantify the extremely confined defect-electron scatterings and isolate the intrinsic phonon-electron scattering that is shared by the bulk Ir. At low temperatures below 50 K, κ of the film has almost two orders of magnitude reduction from that of bulk Ir. The film has ∂κ/∂T > 0, while the bulk Ir has ∂κ/∂T < 0. We introduce a unified thermal resistivity (Θ = T/κ) to interpret these completely different κ ∼ T relations. It is found that the film and the bulk Ir share a very similar Θ ∼ T trend, while they have a different residual part (Θ{sub 0}) at 0 K limit: Θ{sub 0} ∼ 0 for the bulk Ir, and Θ{sub 0} = 5.5 m·K{sup 2}/W for the film. The Ir film and the bulk Ir have very close ∂Θ/∂T (75–290 K): 6.33 × 10{sup −3} m K/W for the film and 7.62 × 10{sup −3} m K/W for the bulk Ir. This strongly confirms the similar phonon-electron scattering in them. Therefore, the residual thermal resistivity provides an unprecedented way to quantitatively evaluating defect-electron scattering (Θ{sub 0}) in heat conduction. Moreover, the interfacial thermal conductance across the grain boundaries is found larger than that of Al/Cu interface, and its value is proportional to temperature, largely due to the electron's specific heat. A unified interfacial thermal conductance is also defined and firmly proves this relation. Additionally, the electron reflection coefficient is found to be large (88%) and almost temperature independent.

  17. Reduced risk for metabolic syndrome and insulin resistance associated with ovo-lacto-vegetarian behavior in female Buddhists: a case-control study.

    Directory of Open Access Journals (Sweden)

    Jui-Kun Chiang

    Full Text Available 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.

  18. Double Peak Behavior of Resistivity-Temperature Curves in (Nd / Pr0.67Sr0.33MnO3 Manganites

    Directory of Open Access Journals (Sweden)

    Bharat Singh

    2014-06-01

    Full Text Available We have reported the synthesis of polycrystalline samples of R0.67Sr0.33MnO3 (R  Pr, Nd from the precursors of PrMnO3, NdMnO3 and SrMnO3 by using solid state reaction method. These samples were sintered at 1200 °C and 1400 °C. Some of samples were also undergone oxygen annealing at 950 °C for 6 h. All the synthesized samples were characterized by X-Ray diffraction (XRD technique, scanning electron microscopy (SEM and low temperature resistivity versus temperature (R-T measurement. The XRD patterns show the monophasic nature of the sintered and annealed samples. The sintered samples of Nd0.67Sr0.33MnO3 has metal- insulator transition at 250 K, while the sample annealed in oxygen shows two peaks, one sharp peak at 250 K and other broad peak at 200 K. The sintered samples of Pr0.67Sr0.33MnO3 has only one peak at 290 K, while the sample annealed in oxygen shows two peaks, one sharp peak at 290 K and another broad peak at 225 K. The two peak behavior in the annealed samples has been explained by inhomogeneous diffusion of oxygen in the core of the grain and at the grain boundaries region.

  19. Thermopower and electrical resistivity behavior near the martensitic transition in Gd{sub 5}(Si{sub x}Ge{sub 1-x}){sub 4} magnetocaloric compounds

    Energy Technology Data Exchange (ETDEWEB)

    Pinto, R.P. [IFIMUP, Rua do Campo Alegre, 678, 4169-007 Porto (Portugal); Sousa, J.B. [IFIMUP, Rua do Campo Alegre, 678, 4169-007 Porto (Portugal)]. E-mail: jbsousa@fc.up.pt; Correia, F.C. [IFIMUP, Rua do Campo Alegre, 678, 4169-007 Porto (Portugal); Araujo, J.P. [IFIMUP, Rua do Campo Alegre, 678, 4169-007 Porto (Portugal); Braga, M.E. [IFIMUP, Rua do Campo Alegre, 678, 4169-007 Porto (Portugal); Pereira, A.M. [IFIMUP, Rua do Campo Alegre, 678, 4169-007 Porto (Portugal); Morellon, L. [DFMC and ICMA, Univ. De Zaragoza.-CSIC, 50009 Zaragoza (Spain); Algarabel, P.A. [DFMC and ICMA, Univ. De Zaragoza.-CSIC, 50009 Zaragoza (Spain); Magen, C. [DFMC and ICMA, Univ. De Zaragoza.-CSIC, 50009 Zaragoza (Spain); Ibarra, M.R. [DFMC and ICMA, Univ. De Zaragoza.-CSIC, 50009 Zaragoza (Spain)

    2005-04-15

    Recently, the Gd{sub 5}(Si{sub x}Ge{sub 1-x}){sub 4} system exhibits fascinating physical properties, namely giant magnetocaloric, magnetoresistance and magnetostriction effects near a first-order (martensitic like; T=T{sub S}) magneto-structural transition. We report the thermopower behavior S(T) between 10 and 300K for compounds with x=0, 0.10 and 0.45, belonging to three distinct regions of the magnetic/structural phase diagram. Large thermopower changes are observed near T{sub S} for x=0.10 (T{sub S}=78K; AFM-Orthorhombic II/FM-Ortho.I) and for x=0.45 (T{sub S}=242K; PM-Monoc/FM-Ortho.I) with a Gaussian distribution in dS/dT, characteristic of a first-order phase transition. Near the purely magnetic transitions (PM/AFM) for x=0(T{sub N}=122K) and x=0.10(T{sub N}=127K) we observe dS/dT peaks governed by spin fluctuation effects. A comparative analysis between dS/dT and the resistivity derivative d{rho}/dT near T{sub S} is made. At low temperatures S(T) behaves similarly in the ferromagnetic x=0.10 and 0.45 compounds (S{approx}AT+BT{sup 2}), the anomalous B term being related to the mean internal field (spin wave excitations). For x=0 (AFM phase at low T) one has S=AT (no B term; zero mean internal field)

  20. Crystal micromorphologies and forming voltage effect on resistance switching behaviors in Ti/Pr(Sr{sub 0.1}Ca{sub 0.9}){sub 2}Mn{sub 2}O{sub 7}/Pt devices

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Yuchen; Song, Liwei; Hua, Lifang; Cai, Wenhui; Chen, Wei [College of Physics Science & Information Engineering, Hebei Normal University, Shijiazhuang 050024 (China); Key Laboratory of Advanced Films of Hebei Province, Shijiazhuang 050024 (China); Zhao, Xu, E-mail: xzhao@hebtu.edu.cn [College of Physics Science & Information Engineering, Hebei Normal University, Shijiazhuang 050024 (China); Key Laboratory of Advanced Films of Hebei Province, Shijiazhuang 050024 (China)

    2015-10-15

    Two Pr(Sr{sub 0.1}Ca{sub 0.9}){sub 2}Mn{sub 2}O{sub 7} (PSCMO)-based devices (Ti/PSCMO-1/Pt and Ti/PSCMO-2/Pt) have been prepared by pulsed laser deposition, and the micromorphology of the films can be controlled through the different deposition condition. PSCMO-1 film with a smaller grain size grows with a near-random arrangement, whereas columnar grains with a larger grain size appear in the Ti/PSCMO-2/Pt device. The I–V curves in Ti/PSCMO-2/Pt device show the higher resistance ratio and larger hysteresis than that in the Ti/PSCMO-1/Pt device without forming process. The electron transport property in the PSCMO-2 film shows the higher resistance and metal behavior in room temperature. By fitting the I–V curves, we found that the conduction process in Ti/PSCMO-1/Pt device is dominated by Schottky barrier mechanism, but the conduction behavior in Ti/PSCMO-2/Pt device are dominated by trap-charged space-charge-limited current (SCLC) mechanism. Interesting, after a forming process, the Ti/PSCMO-1/Pt device also displays the higher resistance ratio and larger hysteresis, which can be explained by SCLC mechanism. Our results suggest that the crystal micromorphology and grain size may play a critical role in oxygen vacancy movement, and result in the transformation of resistance switching along with a higher resistance ratio and larger hysteresis in the Ti/PSCMO-2/Pt device. - Highlights: • Two different Pr(Sr{sub 0.1}Ca{sub 0.9}){sub 2}Mn{sub 2}O{sub 7}-based devices have been prepared. • The device with larger grain and columnar arrangement shows higher resistance ratio. • Crystal morphologies and grain size play critical role in oxygen vacancy movement.

  1. Influences of MCrAlY coatings on oxidation resistance of single crystal superalloy DD98M and their inter-diffusion behaviors

    Energy Technology Data Exchange (ETDEWEB)

    Shi, Long [School of Materials and Metallurgy, Northeastern University, Shenyang 110819 (China); Laboratory for Corrosion and Protection, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016 (China); Xin, Li, E-mail: xli@imr.ac.cn [Laboratory for Corrosion and Protection, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016 (China); Wang, Xinyue; Wang, Xiaolan; Wei, Hua; Zhu, Shenglong; Wang, Fuhui [Laboratory for Corrosion and Protection, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016 (China)

    2015-11-15

    Oxidation and interdiffusion behaviors of Ni-based single crystal superalloy DD98M with nominal compositions Ni–5.0Co–6.0Cr–6.3Al–6.0W–2.0Mo–6.0Ta–1.0Ti (in wt.%) and two types of MCrAlY coatings at 1000 °C and 1050 °C were investigated. Complex oxides formed on the surface of DD98M alloy when oxidized at 1000 °C and 1050 °C, which stratified, cracked and spalled. The faceted-like AlN and the particle-like and strip-like TiN formed in the alloy. The application of the NiCrAlY and NiCoCrAlYHfSi coatings greatly improved the oxidation resistance of DD98M alloy. After 500 h oxidation, α-Al{sub 2}O{sub 3} was still the dominate phase in the oxide scales formed on the coated specimens. The adhesion of the oxide scale on the NiCoCrAlYHfSi coating was much better than that on the NiCrAlY coating. Interdiffusion occurred between the coatings and the substrate, which led to the formation of the IDZ and SRZ. The IDZ of the NiCrAlY coated specimen was composed of γ phase and Al- and Ta-rich γ′ phase. The γ′ phase in the IDZ accommodated most of the inward diffusing aluminum, so the SRZ formation was suppressed when oxidized at 1050 °C. However the formation of SRZ with μ-TCP still occurred when oxidized at 1000 °C probably due to the low solubility and slow diffusion rate of the alloying elements at lower temperature. The IDZ of the NiCoCrAlYHfSi coated specimen was a single γ phase. A large amount of μ-TCP precipitated in the SRZ of the NiCoCrAlYHfSi coated specimen when oxidized at 1000 °C and 1050 °C. It can be concluded coating composition has a significant effect on the development of the IDZ and SRZ. Thermal exposure temperature also has influences on the formation of the SRZ. The mechanism of SRZ formation and TCP precipitation are discussed. - Graphical abstract: The TEM micrograph of the IDZ and SRZ of the NiCoCrAlYHfSi-coated specimen oxidized at 1050 °C for 100 h and the respective diffraction patterns of the needle-like and the

  2. Resistance-resistant antibiotics.

    Science.gov (United States)

    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.

  3. EFFECT ON BIOLOGICAL BEHAVIOR OF CHEMOTHERAPY-RESISTANT TUMOR CELLS BY HUMAN WILD-TYPE P53, GM-CSF AND B7-1 GENES VIA RECOMBINANT ADENOVIRUS

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Objective: To explore the effect on biological behavior of chemotherapy-resistant tumor cells by human wild-type p53, GM-CSF and B7-1 genes mediated via recombinant adenovirus. Methods: p53-abnormal KB-v200 (VCR resistant) and KB-s (VCR sensitive) cell lines were used as model tumor cells, which are resistant and sensitive to chemotherapeutic drugs respectively. After infected with recombinant adenovirus carrying human wild-type p53, GM-CSF and B7-1 genes, changes in biological behavior (including drug sensitivity) of these two kinds of gene-transduced cancer cells were observed. Results: Both of the cell lines were susceptible to adenovirus, all of three exogenous genes (p53, GM-CSF and B7-1) could be effectively expressed in these cell lines, their growth was suppressed, and apoptosis was induced. The drug-pumping-out function of Pgp glycoprotein on the cytomembrane of drug-resistant KB-v200 cells was markedly affected 48h after transfection of the recombinant adenovirus, revealed by increase of the amount of rhodamine 123 accumulation in the cells. The MTT assay also indicated the reversal of their sensitivity to VCR drugs. In vivo experiment in nude mice it was demonstrated reduction of tumorigenicity of the KB-v200 cells or KB-s cells infected with the recombinant adenovirus, and increase of their sensitivity to VCR. Conclusion: The clinical application of this recombinant adenovirus carrying agents might be more effective in treatment of tumors with multidrug resistance (MDR).

  4. Enhanced resistive switching and multilevel behavior in bilayered HfAlO/HfAlO{sub x} structures for non-volatile memory applications

    Energy Technology Data Exchange (ETDEWEB)

    Faita, F. L., E-mail: fabriciofaita@gmail.com [Centre of Physics, University of Minho, Campus de Gualtar, 4710-057 Braga (Portugal); Departamento de Física, Universidade Federal de Santa Catarina, Campus Trindade, 88040-900 Florianópolis, SC (Brazil); Silva, J. P. B., E-mail: josesilva@fisica.uminho.pt [Centre of Physics, University of Minho, Campus de Gualtar, 4710-057 Braga (Portugal); IFIMUP and IN-Institute of Nanoscience and Nanotechnology, Departamento de Física e Astronomia, Faculdade de Ciências da Universidade do Porto, 4169-007 Porto (Portugal); Pereira, M.; Gomes, M. J. M. [Centre of Physics, University of Minho, Campus de Gualtar, 4710-057 Braga (Portugal)

    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. Role of tantalum nitride as active top electrode in electroforming-free bipolar resistive switching behavior of cerium oxide-based memory cells

    Energy Technology Data Exchange (ETDEWEB)

    Ismail, Muhammad, E-mail: ismailmalikbzu10@gmail.com [Department of Physics, Bahauddin Zakariya University, Multan 60800 (Pakistan); Ahmed, Ejaz; Rana, Anwar Manzoor; Talib, Ijaz; Khan, Tahira [Department of Physics, Bahauddin Zakariya University, Multan 60800 (Pakistan); Iqbal, Khalid [Department of Radiation Oncology, Shaukat Khanum Memorial Cancer Hospital and Research Centre, Lahore (Pakistan); Nadeem, Muhammad Younus [Department of Physics, Bahauddin Zakariya University, Multan 60800 (Pakistan)

    2015-05-29

    Electroforming-free cerium oxide-based bipolar resistive switching memory devices have been deposited using radio frequency magnetron sputtering technique. These devices demonstrate two types of forming-free cells: some in the low-resistance state and the others in high-resistance state. The transmission electron microscopy and X-ray diffraction analyses illustrate the formation of tantalum oxynitride layer between tantalum nitride (TaN) and cerium oxide (CeO{sub x}), which looks to be responsible for the two types of cells as well as their memory performance. Ohmic and Poole-Frenkel conduction mechanisms are found to be responsible for charge transport in the low- and high-resistance states. The current-voltage characteristics and temperature dependence of resistance suggest that resistive switching mechanism in our TaN/CeO{sub x}/Pt devices may be explained by the model of connection and disconnection of filamentary paths made of oxygen vacancies. The reliability characteristics of TaN/CeO{sub x}/Pt devices indicate better endurance and stable retention performance at relatively lower programming voltages and larger memory window (OFF/ON resistance ratio ~ 10{sup 3}) at room temperature and at 100 °C. - Highlights: • Electroforming-free TaN/CeO{sub x}/Pt memory cells have been fabricated by sputtering. • Device exhibits good endurance, long data retention and high-resistance window (~ 10{sup 3}). • Voltages for SET and RESET transitions of our device exhibit narrow distribution. • The device is forming-free due to pre-existence of abundant oxygen vacancies. • TaN top electrode play major role in uniformity of resistive switching characteristics.

  6. Effects of X-rays Radiation on AISI 304 Stainless Steel Weldings with AISI 316L Filler Material: A Study of Resistance and Pitting Corrosion Behavior

    Directory of Open Access Journals (Sweden)

    Francisco Javier Cárcel-Carrasco

    2016-04-01

    Full Text Available This article investigates the effect of low-level ionizing radiation, namely X-rays, on the micro structural characteristics, resistance, and corrosion resistance of TIG-welded joints of AISI 304 austenitic stainless steel made using AISI 316L filler rods. The welds were made in two different environments: natural atmospheric conditions and a closed chamber filled with inert argon gas. The influence of different doses of radiation on the resistance and corrosion characteristics of the welds is analyzed. Welded material from inert Ar gas chamber TIG showed better characteristics and lesser irradiation damage effects.

  7. Numerical Simulation of Mechanical Behaviors of the TiNi Shape Memory Alloy Welded Joints in the Precise Pulse Resistance Butt-Welding

    Institute of Scientific and Technical Information of China (English)

    Lijun HAN; Junjie ZHU; Lihong HAN

    2003-01-01

    The hysteresis unit system was introduced to mechanical structure behavior of the TiNi SMA joint based on the structure characteristics of the martensite variants in the joints, and some functions reflecting its inner structure characteristics and micro-behavior such as density function, phase transformation function were set up from micropoints. Finally, the structure behavior relationship and corresponding mathematic model reflecting the relationship among hysteresis strain, stress and phase transformation strain were provided, which could predict the stress-strain behavior of the TiNi SMA joint to large extent.

  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

    Science.gov (United States)

    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. Structure and optical properties of polycrystalline NiO films and its resistive switching behavior in Au/NiO/Pt structures

    Energy Technology Data Exchange (ETDEWEB)

    Lai, J.C. [Tianjin Key Laboratory of Film Electronic & Communicate Devices, School of Electronics Information Engineering, Tianjin University of Technology, Tianjin 300384 (China); Wang, X.C., E-mail: wangxccn@126.com [Tianjin Key Laboratory of Film Electronic & Communicate Devices, School of Electronics Information Engineering, Tianjin University of Technology, Tianjin 300384 (China); Mi, W.B. [Tianjin Key Laboratory of Low Dimensional Materials Physics and Preparation Technology, Faculty of Science, Tianjin University, Tianjin 300072 (China); Ding, Y.H.; Yang, B.H. [Tianjin Key Laboratory of Film Electronic & Communicate Devices, School of Electronics Information Engineering, Tianjin University of Technology, Tianjin 300384 (China)

    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.

  10. Resistive switching and magnetic behavior of Bi0.8Ba0.2FeO3 / SrRuO3 / SrTiO3 films: role of thickness-dependent strain

    Science.gov (United States)

    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.

  11. Shear-resistant behavior of concrete frame columns subjected to velocity pulse-like excitations%速度脉冲激励作用下混凝土框架柱抗剪性能研究

    Institute of Scientific and Technical Information of China (English)

    周靖; 方小丹

    2011-01-01

    The shear-resistant behavior of concrete frame columns subjected to velocity pulse-like excitations was studied. The first floor columns of reinforced concrete frame structures were used to investigate the effects of vertical and horizontal velocity pulse-like excitations on shear-resistant behavior of concrete columns. Three equivalent sine velocity pulses were taken as earthquake import to execute nonlinear dynamic time history analysis. Combined effects of vertical-to-· horizontal peak acceleration ratio, import time difference of peak values between vertical and horizontal excitations, shear-span ratio, and fundamental period on shear-resistant demand and shear-resistant capacity were analyzed with the assessment of the effect of velocity pulse action. The results demonstrated that shear-resistant demand of concrete columns increases with increase in intensity of velocity pulse, and shear-resistant capacity decreases with increase in vertical-to-horizontal peak values ratio; import time difference between vertical and horizontal excitations has an important influence on the most unfavorable shear-resistant behavior of concrete frame columns; the higher the values of shear-span ratio, the more significant the influence of velocity pulse excitations; the nonlinear regression analysis for the above results is conducted, and an empirical approach considering different effect of these factors is proposed.%研究等效速度脉冲地震作用下混凝土框架柱最不利抗剪性能.以混凝土框架结构底层柱为分析对象,采用等效正弦速度脉冲激励作为地震动输入,通过非线性动力时程分析,研究竖直和水平向联合速度脉冲地震作用对框架柱抗剪性能的影响,分析速度脉冲地震作用与竖向和水平向加速度峰值比、峰值输入时差、剪跨比以及基本振动周期等对抗剪需求和抗剪承载力的交互影响规律.结果表明:脉冲速度强度增大,框架柱抗剪需求增大;竖向与

  12. Drug Resistance

    Science.gov (United States)

    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, ...

  13. Antibiotic Resistance

    Science.gov (United States)

    ... lives. But there is a growing problem of antibiotic resistance. It happens when bacteria change and become able ... resistant to several common antibiotics. To help prevent antibiotic resistance Don't use antibiotics for viruses like colds ...

  14. COMPARE THE BEHAVIOR FACTOR OF THE ULTIMATE RESISTANCE OF MOMENT FRAME, PLAIN AND PERFORATED STEEL PLATE SHEAR WALLS AND BUCKLING RESTRAINED BRACE AS YIELDING METAL DAMPER

    OpenAIRE

    Hamid Reza Ashrafi; Peyman Beiranvand; Kasra Shahbazian; Shaahin Bidmeshki; Somaye Yaghooti

    2016-01-01

    Steel moment frame systems, steel plate shear walls and also buckling restrained brace (BRB) are considered as the most widely used seismic resistant systems of the world. Firstly, in this research, in order to validate the finite element models, the tested sample of steel plate shear walls of 4 floors at the University of Alberta, Canada, and the tested sample of buckling restrained brace at the University of Berkeley California, with the software ABAQUS 6.10-1 were used. Then, the obtained ...

  15. Stop Thinking and Start Doing: Switching from Cognitive Therapy to Behavioral Activation in a Case of Chronic Treatment-Resistant Depression

    Science.gov (United States)

    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…

  16. 氮化硼纳米管增强氮化硅复合材料的裂纹扩展阻力行为%Crack propagation resistance behavior of Si3N4 composites reinforced by BN nanotubes

    Institute of Scientific and Technical Information of China (English)

    于航海; 王守仁; 杨丽颖

    2012-01-01

    ceramics crack propagation capability and that Si3 N4 ceramics added BNNT has clear appreciation of the resistance curve behavior. The finite element simulation results on the crack tip stress indicate that BNNT makes maximum stress of the crack tip to deflect nanotubes and reduce stress of the Si3 N4 ceramics crack tip, which can improve the crack propagation resistance behavior of Sis N4 ceramics.

  17. Metabolic Resistance in Bed Bugs

    Directory of Open Access Journals (Sweden)

    Omprakash Mittapalli

    2011-03-01

    Full Text Available 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.

  18. Viscous, Resistive Magnetorotational Modes

    DEFF Research Database (Denmark)

    Pessah, Martin Elias; Chan, Chi-kwan

    2008-01-01

    We carry out a comprehensive analysis of the behavior of the magnetorotational instability (MRI) in viscous, resistive plasmas. We find exact, non-linear solutions of the non-ideal magnetohydrodynamic (MHD) equations describing the local dynamics of an incompressible, differentially rotating...

  19. Analysis of the Long-Term Corrosion Behavior of X80 Pipeline Steel in Acidic Red Soil Using Electrical Resistance Test Technique

    Directory of Open Access Journals (Sweden)

    Shuaixing Wang

    2015-01-01

    Full Text Available The long-term corrosion rate of X80 steel in an acidic red soil was monitored in situ by using a precise electrical resistance (ER test system. The corrosion characteristics of X80 steel were examined via SEM, EDS, and XRD. The results indicated that the corrosion rate determined from ER test was very similar to that obtained from the mass loss test. The ER test technique made it possible to predict the long-term corrosion rate of steel in soil in situ. The corrosion rate of X80 steel in acidic red soil was about 0.0902 mm/a at 38 weeks, but the corrosion rate was dropped to 0.0226 mm/a after 5 years. The final corrosion product layer was composed mainly of FeOOH, γ-Fe2O3, and FeCO3.

  20. COMPARE THE BEHAVIOR FACTOR OF THE ULTIMATE RESISTANCE OF MOMENT FRAME, PLAIN AND PERFORATED STEEL PLATE SHEAR WALLS AND BUCKLING RESTRAINED BRACE AS YIELDING METAL DAMPER

    Directory of Open Access Journals (Sweden)

    Hamid Reza Ashrafi

    2016-03-01

    Full Text Available Steel moment frame systems, steel plate shear walls and also buckling restrained brace (BRB are considered as the most widely used seismic resistant systems of the world. Firstly, in this research, in order to validate the finite element models, the tested sample of steel plate shear walls of 4 floors at the University of Alberta, Canada, and the tested sample of buckling restrained brace at the University of Berkeley California, with the software ABAQUS 6.10-1 were used. Then, the obtained results of the test and analysis have been compared. The confirmed models have been used for the analysis of two-dimensional frame of plain and perforated steel plate shear walls with a regular pattern of positing holes in the screen, buckling restrained brace and moment frame of 4 floors.

  1. 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

    Science.gov (United States)

    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

  2. Resistance to Disruption in a Classroom Setting

    Science.gov (United States)

    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…

  3. Correlation of Electrical Resistance to CMC Stress-Strain and Fracture Behavior Under High Heat-Flux Thermal and Stress Gradients

    Science.gov (United States)

    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.

  4. Antimicrobial Resistance

    Science.gov (United States)

    ... emergence and spread of antibacterial resistance, including optimal use of antibiotics in both humans and animals. A global action plan on antimicrobial resistance was adopted by Member States at the ...

  5. Enhanced salt resistance in apple plants overexpressing a Malus vacuolar Na+/H+ antiporter gene is associated with differences in stomatal behavior and photosynthesis.

    Science.gov (United States)

    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.

  6. 昆虫抗药性机理:行为和生理改变及解毒代谢增强%Behavioral change, physiological modification, and metabolic detoxification: mechanisms of insecticide resistance

    Institute of Scientific and Technical Information of China (English)

    刘喃喃; 朱芳; 徐强; Julia W.PRIDGEON; 高希武

    2006-01-01

    Insecticide resistance is "the development of an ability in a strain of some organisms to tolerate doses of a toxicant which would prove lethal to a majority of individuals in a normal population of the same species".Mechanisms of resistance, such as behavioral change, physiological modification or metabolic detoxification, decrease the effective dose available at the target site. Behavioral resistance is defined as any behavior that reduces an insect's exposure to toxic compounds or that allows an insect to survive in an environment that is harmful and/or fatal to the majority of insects. Physiological modification mechanisms permit insects to survive lethal doses of a toxicant through decreased penetration of insecticides, increased sequestration/storage of insecticides, and accelerated excretion of insecticides. Metabolic detoxification is conferred by cytochrome P450 monooxygenases (cytochrome P450s),hydrolases, and glutathione transferases (GSTs). Cytochrome P450s constitute the largest gene superfamily and are critical for the detoxification and/or activation of xenobiotics and the metabolism of endogenous compounds. Increased P450-mediated detoxification has been found in many insect species, resulting in enhanced insecticide resistance.Glutathione transferases (GSTs) are soluble dimeric proteins involved in the metabolism, detoxification, and excretion of a large number of endogenous and exogenous compounds. Elevated GST activities have been implicated in resistance in many insect species. Hydrolases or esterases, a group of heterogeneous enzymes, have been identified as the active agents promoting hydrolase-mediated resistance that protect insects by either binding and sequestering insecticides through overproduction of proteins, or enhancing the metabolism of insecticides through increased enzyme activities.%杀虫剂抗性是指"生物的一个品系发展了对该生物正常种群中大多数个体具有致死作用剂量的杀虫药剂的能力".行

  7. 纯钛材离子渗氮后在Hank's人工模拟体液中的电化学性能%Electrochemical Behavior and Corrosion Resistance of Ion Nitriding Layer on Titanium Substrate in Artificially Simulated Body Solution

    Institute of Scientific and Technical Information of China (English)

    吴新春; 陈吉; 韩啸

    2013-01-01

    As-cast Ti substrate was ion nitridized so as to increase the surface hardness and corrosion resistance as well as compatibility to human body. The elemental composition, phase structure, and morphology of as - obtained ion nitriding layer were analyzed with an energy dispersive spectrometer, an X-ray diffractometer, and a scanning electron microscope, while its hardness was measured with a hardness meter. Moreover, the electrochemical behavior and corrosion resistance of as - cast Ti substrate and the ion nitriding layer in Hank' s solution of 37 ℃ were comparatively investigated based on measurements of potentiodynamic polarization curves and alternating current impedance spectra. It was found that a gradient ion nitriding layer with a thickness of 17 μm was formed on Ti substrate surface after ion nitriding at 650 ℃. As -obtained ion nitriding layer consisted of α - Ti ( N) , Ti2 N and TiN. Moreover, the ion nitriding layer had a hardness of about (650 ±20) HV, which was 2. 3 times as much as that of the Ti substrate, while the Ti substrate after ion nitriding possessed greatly improved corrosion resistance.%为了提高纯钛材的表面硬度及耐蚀性,使之更适应人体环境,对铸态纯钛材表面进行离子渗氮.利用能谱仪、X射线衍射仪、扫描电镜及显微硬度计研究了渗氮钛材的成分、相结构、形貌及硬度,利用动电位极化曲线及交流阻抗谱对比研究了纯钛材及离子渗氮钛材在37℃的Hank's人工模拟体液中的电化学行为.结果表明:经过650℃渗氮处理后,铸态纯钛材表面形成了17 μm的梯度渗氮层,其相组成为α-Ti(N),Ti2N,TiN;表面显微硬度约为(650±20) HV,为铸态纯钛材的2.3倍;离子渗氮钛材的耐蚀性明显提高.

  8. Camptothecin resistance

    DEFF Research Database (Denmark)

    Brangi, M; Litman, Thomas; Ciotti, M;

    1999-01-01

    The mitoxantrone resistance (MXR) gene encodes a recently characterized ATP-binding cassette half-transporter that confers multidrug resistance. We studied resistance to the camptothecins in two sublines expressing high levels of MXR: S1-M1-80 cells derived from parental S1 colon cancer cells...... and MCF-7 AdVp3,000 isolated from parental MCF-7 breast cancer cells. Both cell lines were 400- to 1,000-fold more resistant to topotecan, 9-amino-20(S)-camptothecin, and the active metabolite of irinotecan, 7-ethyl-10-hydroxycamptothecin (SN-38), than their parental cell lines. The cell lines...... demonstrated much less resistance to camptothecin and to several camptothecin analogues. Reduced accumulation and energy-dependent efflux of topotecan was demonstrated by confocal microscopy. A significant reduction in cleavable complexes in the resistant cells could be observed after SN-38 treatment...

  9. Viscous, Resistive Magnetorotational Modes

    CERN Document Server

    Pessah, Martin E

    2008-01-01

    We carry out a comprehensive analysis of the behavior of the magnetorotational instability (MRI) in viscous, resistive plasmas. We find exact, non-linear solutions of the non-ideal magnetohydrodynamic (MHD) equations describing the local dynamics of an incompressible, differentially rotating background threaded by a vertical magnetic field when disturbances with wavenumbers perpendicular to the shear are considered. We provide a geometrical description of these viscous, resistive MRI modes and show how their physical structure is modified as a function of the Reynolds and magnetic Reynolds numbers. We demonstrate that when finite dissipative effects are considered, velocity and magnetic field disturbances are no longer orthogonal (as it is the case in the ideal MHD limit) unless the magnetic Prandtl number is unity. We generalize previous results found in the ideal limit and show that a series of key properties of the mean Reynolds and Maxwell stresses also hold for the viscous, resistive MRI. In particular, ...

  10. [Psychological resistances of women to the principal female methods of contraception. Clinical classification].

    Science.gov (United States)

    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.

  11. 不同条件下桩侧阻力端阻力性状及侧阻力分布概化与应用%Behaviors of shaft resistance and tip resistance of piles under different conditions and conceptualization and application of distribution of shaft resistance

    Institute of Scientific and Technical Information of China (English)

    刘金砺; 秋仁东; 邱明兵; 高文生

    2014-01-01

    根据24组51根桩竖向静载试验的侧阻力端阻力测试结果分析表明,桩侧土层性质与分布、桩长径比、后注浆效应是影响侧阻性状与分布的主要因素。软土中的桩其侧阻发挥正常,分布模式不受长径比影响;碎石土、砂土侧阻在桩顶以下约5d深度范围呈现应变软化,随深度增加逐渐演变为应变硬化导致桩身下部侧阻发挥滞后或发挥值显著降低,侧阻分布模式异化;土愈硬、长径比愈大,侧阻分布模式异化愈明显;后注浆对侧阻的增强与分布模式的影响,碎石土、砂土远甚于其它类土。工作荷载下的侧阻分布模式可概化为正梯形、倒梯形、橄榄形、灯笼形、蒜头形、峰谷形六种模式。端阻比随侧阻增强,随长径比增大而降低,随荷载水平提高呈非线性增长,给出了工作荷载下端阻比经验参考值。将每种侧阻概化模式分解为桩长l、kl的矩形、三角形分布侧阻单元,据此可查表确定供沉降计算的Mindlin解附加应力系数。计算结果表明,除正梯形和蒜头形分布外,其附加应力积分值按Geddes正梯形分布假定计算附加应力比实测侧阻概化分布大15%~74%,侧阻分布重心愈高差异愈大。%According to the analysis of the results of the vertical static load tests on shaft resistance and tip resistance of 51 piles in 24 groups, the soil properties and vertical distribution, ratio of length to diameter of piles and post-grouting effect are the main factors affecting the characteristics and distribution of the shaft resistance. In soft soils, the shaft resistance of piles plays a normal function, and its distribution pattern is not affected by the ratio of length to diameter. In gravel and sand, the shaft resistance below ground about 5d depth exhibits strain softening and gradually evolves into strain hardening, which leads to the result that it lags or decreases significantly with the

  12. Antibiotic Resistance

    DEFF Research Database (Denmark)

    Munck, Christian

    morbidity and mortality as well as an increase in the cost of treatment. Understanding how bacteria respond to antibiotic exposure gives the foundations for a rational approach to counteract antimicrobial resistance. In the work presented in this thesis, I explore the two fundamental sources...... of antimicrobial resistance: (1) adaptive mutations and (2) horizontal acquisition of resistance genes from antibiotic gene reservoirs. By studying the geno- and phenotypic changes of E. coli in response to single and drug-pair exposures, I uncover the evolutionary trajectories leading to adaptive resistance. I...... to rationally design drug combinations that limit the evolution of antibiotic resistance due to counteracting evolutionary trajectories. My results highlight that an in-depth knowledge about the genetic responses to the individual antimicrobial compounds enables the prediction of responses to drug combinations...

  13. Resistance to disruption in a classroom setting.

    Science.gov (United States)

    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.

  14. Aditivos e sua influência no comportamento de secagem e resistência à tração de concretos refratários Additives and their influence in the refractory castables drying and traction strength behavior

    Directory of Open Access Journals (Sweden)

    I. R. Oliveira

    2007-12-01

    Full Text Available A evolução tecnológica de concretos refratários tem tornado mais difícil a etapa de secagem devido a redução da sua permeabilidade e conseqüente aumento da dificuldade para que o vapor de água migre do interior do corpo para a superfície. A hidratação do cimento de aluminato de cálcio também causa decréscimo da permeabilidade dos concretos. Tal processo é significativamente afetado pela presença de aditivos utilizados para a dispersão do concreto. Neste contexto, este trabalho teve como objetivo relacionar o tipo de aditivo utilizado no processamento de concretos refratários com seu comportamento de secagem e resistência à tração. Foi verificado que os aditivos não atuam somente na dispersão das partículas da matriz e ligante, mas o efeito da sua atuação pode influenciar no tipo de hidrato formado. O aditivo CS se mostrou um eficiente dispersante promovendo a redução no consumo de água. Isso acarretou na formação preferencial dos hidratos C3AH6 disponibilizando mais alumina para a formação de AH3. Essa fase apresenta alta capacidade de preencher vazios interparticulas contribuindo para aumentar a resistência à tração do material. Por outro lado, o aditivo AC desfavoreceu a formação desses tipos de hidratos uma vez que atua como retardador da hidratação do cimento por meio do consumo de íons cálcio. Também a presença de um maior teor de água nos concretos preparados com este aditivo pode explicar o aumento da porosidade e decréscimo da resistência à tração do concreto.The growing technology applied in the refractory castables production has become more difficult the drying process due the reduction of their permeability and the consequent increasing difficult of vapor migration from the inner region of the body to the surface. The hydration of calcium aluminate cement is also responsible for the castables permeability reduction. This process is significatively affected by the presence of

  15. 预制夹芯保温墙体板缝抗火性能试验研究%Experimental research on fire-resistance behavior of precast sandwich insulation wall panel joints

    Institute of Scientific and Technical Information of China (English)

    李志杰; 秦桁; 刘国权; 薛伟辰

    2012-01-01

    According to the test methods of the national standard Plastics—Determination of burning characteristics—Horizontal and vertical test(GB/T 2408—2008),experimental research on fire-resistance behavior for three kinds of wall panel joints about the precast sandwich insulation wall panels(including no filler material wall panel joint,filling PE foam wall panel joint and filling rock wool wall panel joint) were done using the Bunsen burner.The results indicate that when no filler material wall panel joint was fired 30 minutes(the maximum flame temperature is 957℃),the highest temperature of FRP connector is 132℃ in internal wall panel and 97℃ in the external wall panel,respectively.It exceeds the glass transition temperature 93℃ of the FRP material.The XPS material burnt strongly and melting at this moment.It proves that fire-resistance behavior of no filler material wall panel joint is poorer,and can not satisfy the requirement of fire safety.After fired 60 minutes,the highest flame temperature is about 970℃.The FRP connectors are remain intact for filling PE foam wall panel joint and filling rock wool wall panel joint.The highest temperature of filling PE foam wall panel joint is 78℃ in the internal wall panel and 42℃ in the external wall panel,respectively.The highest temperature of filling rock wool wall panel joint is 47℃ in the internal wall panel and 36℃ in the external wall panel,respectively.The XPS material for the two kinds of wall panel joints does not produce flame or drop things at this moment.It shows that wall panel joints filled with PE foam or filled with rock wool have good fire-resistance behavior,and are applicable in the practical projects.%按照国家标准《塑料燃烧性能的测定水平法和垂直法》(GB/T 2408—2008)的有关试验方法,采用本生灯对预制夹芯保温墙体的3种板缝构造(无填充材料、填充PE棒泡沫条以及填充岩棉条)的抗火性能进行了试验研究。研究

  16. Lantibiotic resistance.

    Science.gov (United States)

    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.

  17. Messages on "Resistance to change" in German change management approaches

    OpenAIRE

    Fassauer, Gabriele

    2015-01-01

    "Resistance to change" is one of the most important topics of change management in organizations. The paper investigates the analytical framing of „resistance“ and the „resistant employee“ in established German literature on change management. The analysis reveals three main messages referring the characteristics of resistance and the resistant change recipient. These are 1) that resistance is a „natural“, nearly inevitable phenomenon in organizational change processes, 2) that every behavior...

  18. Quantum criticality and DBI magneto-resistance

    Science.gov (United States)

    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).

  19. Androgen resistance.

    Science.gov (United States)

    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.

  20. Anticoagulant Resistance

    DEFF Research Database (Denmark)

    Heiberg, Ann-Charlotte

    Although sewer rat control is carried out in more than 80 % of all Danish municipalities, with usage of large amounts of anticoagulant rodenticides, knowledge on anticoagulant resistance among rats living in the sewers is limited. As rat problems in urban areas are believed to be related to sewer...... problems (70-90 % in UK and DK) unawareness of resistance amongst these populations of Brown rats may constitute a future control problem and knowledge on this issue has become crucial. Rats were captured in sewers from seven different locations in the suburban area of Copenhagen. Locations was chosen...... to represent different sewer rat management strategies i) no anticoagulants for approx. 20 years ii) no anticoagulants for the last 5 years and iii) continuous control for many years. Animals were tested for resistance to bromadiolone by Blood-Clotting Response test, as bromadiolone is the most frequently used...

  1. Improving Maladaptive Behaviors Using Sensory Integration Techniques.

    Science.gov (United States)

    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,…

  2. 钢筋混凝土抗震框架连续倒塌行为分析%Analysis of Progressive Collapse Behavior of Earthquake-resistant Reinforced Concrete Frame

    Institute of Scientific and Technical Information of China (English)

    黄华; 刘伯权; 张彬彬; 吴涛

    2014-01-01

    以某抗震设防框架为研究对象,采用S A P2000有限元软件,依次拆除底层纵向边柱、横向边柱、角柱和内柱,研究抗震框架的倒塌破坏行为。以做功平衡原理建立了柱失效处梁配筋调整计算公式,并进行了配筋调整设计。结果表明:7度和8度抗震设防的框架结构仍会发生连续性倒塌,但是抗倒塌能力随着设防等级的提高而提高,抗震设计不能够完全替代抗倒塌设计;柱失效导致结构发生连续坍塌破坏的危险性由小到大依次为内柱、横向边柱、纵向边柱、角柱;梁铰机制在结构抗倒塌中的作用尤其重要,倒塌破坏时以梁的弯曲破坏为主,剪切破坏较少出现;线弹性静力分析计算的供需比最大值一般出现在失效柱上一层的相邻梁上,而非线性静力分析的最大破坏出现在与失效柱相连的梁上,但是二者对结构可能的失效位置判断基本一致。%Using the finite element software SAP2000 , progressive collapse behavior of the earthquake‐resistant reinforced concrete (RC ) frame was investigated when its longitudinal peripheral‐column , transverse peripheral‐column , corner‐column , and interior‐column were removed in turn .Based on energy balance principle ,the formula of the adjustment of the steel bars of the beams connected with the failure column was proposed ,and the adjustment design was done .The results show that RC frame structures in zones with seismic intensity Ⅶ or Ⅷcould develop progressive collapse ,but their collapse resistance will improve with the increasing of their seismic performance levels ,and seismic design can not eventually replace anti‐collapse design .The dangers of the structure progressive collapse caused by column failure from small to big is interior‐column removing ,transverse peripheral‐column removing ,longitudinal peripheral‐column removing ,corner‐column removing .The beam

  3. Drug resistance

    NARCIS (Netherlands)

    Gorter, J.A.; Potschka, H.; Noebels, J.L.; Avoli, M.; Rogawski, M.A.; Olsen, R.W.; Delgado-Escueta, A.V.

    2012-01-01

    Drug resistance remains to be one of the major challenges in epilepsy therapy. Identification of factors that contribute to therapeutic failure is crucial for future development of novel therapeutic strategies for difficult-to-treat epilepsies. Several clinical studies have shown that high seizure f

  4. Anthelmintic resistance.

    Science.gov (United States)

    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

  5. The Ritual Dimensions of Resistance: Clowning and Symbolic Inversion.

    Science.gov (United States)

    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…

  6. [Treatment-resistant schizophrenia].

    Science.gov (United States)

    Yahyaten, O Ben

    2014-01-01

    Schizophrenia is a psychiatric disorder that causes severe cognitive, behavioral and social dysfunction, responsible for a shortening of the life expectancy of patients, with an increased risk of suicide, cardiovascular disease and cancer. The management of patient with schizophrenia is global and atypical antipsychotics, antagonizing dopamine pathway, are the first line pharmacological treatment. Clozapine, the first atypical antipsychotic discovered, is currently still the most effective molecule against schizophrenia, while causing less extrapyramidal side effects. Its particular pharmacological behavior towards serotonergic, muscarinic and NMDA receptors, seems essential to its action. However, clozapine is responsible for immunological and metabolic lethal adverse events, preventing its wider use. Clozapine is therefore reserved for resistant schizophrenia cases. Monitoring patients with different scales such as the Brief Psychiatric Rating Scale and the Positive And Negative Syndrome Scale showed that there were forms of ultra-resistant schizophrenia. The treatment in this case, must be customized to the patient's symptomatology, but the combination of clozapine with other pharmacological or non-pharmacological treatments, shows yet only small improvements.

  7. Antibiotic Resistance

    DEFF Research Database (Denmark)

    Hansen, Malene Plejdrup; Hoffmann, Tammy C; McCullough, Amanda R

    2015-01-01

    Numerous opportunities are available in primary care for alleviating the crisis of increasing antibiotic resistance. Preventing patients from developing an acute respiratory infection (ARI) will obviate any need for antibiotic use downstream. Hygiene measures such as physical barriers and hand...... wrong. Shared decision making might be a solution, as it enables clinician and patient to participate jointly in making a health decision, having discussed the options together with the evidence for their harms as well as benefits. Furthermore, GPs' diagnostic uncertainty - often leading...... will greatly improve the use of antibiotics for ARIs. However, used in concert, combinations are likely to enable clinicians and health care systems to implement the strategies that will reduce antimicrobial resistance in the future....

  8. Resistant starches.

    Science.gov (United States)

    Jenkins, D J; Kendall, C W

    2000-03-01

    Initially, it was hoped that resistant starches (ie, starches that enter the colon) would have clear advantages in the reduction of colon cancer risk and possibly the treatment of ulcerative colitis. Recent studies have confirmed the ability of resistant starch to increase fecal bulk, to increase the molar ratio of butyrate in relation to other short-chain fatty acids, and to dilute fecal bile acids. However, reduction in fecal ammonia, phenols, and N-nitroso compounds have not been achieved. At this point the picture from the standpoint of colon cancer risk reduction is not clear. Nevertheless, there is a fraction of what has been termed resistant starch (RS1), which enters the colon and acts as slowly digested, or lente, carbohydrate. Foods in this class are low glycemic index and have been shown to reduce the risk of chronic disease. They have been associated with systemic physiologic effects such as reduced postprandial insulin levels and higher high-density lipoprotein cholesterol levels. Consumption of low glycemic index foods has been shown to be related to a reduced risk of type 2 diabetes. Type 2 diabetes has in turn been related to a higher risk of colon cancer, especially colon cancer deaths. If carbohydrate has a protective role in colon cancer prevention, it may lie in the systemic effects of low glycemic index foods. The colonic advantages of different carbohydrates, therefore, remain to be documented. However, there is reason for optimism about the possible health advantages of so-called resistant starches that are slowly digested in the small intestine.

  9. Resistance switching of electrodeposited cuprous oxide

    Science.gov (United States)

    Yazdanparast, Sanaz

    In this work, the resistance switching behavior of electrodeposited cuprous oxide (Cu2O) thin films in Au/Cu2O/top electrode (Pt, Au-Pd, Al) cells was studied. After an initial FORMING process, the fabricated cells show reversible switching between a low resistance state (16.6 O) and a high resistance state (0.4 x 106 O). Changing the resistance states in cuprous oxide films depends on the magnitude of the applied voltage which corresponds to unipolar resistance switching behavior of this material. The endurance and retention tests indicate a potential application of the fabricated cells for nonvolatile resistance switching random access memory (RRAM). The results suggest formation and rupture of one or several nanoscale copper filaments as the resistance switching mechanism in the cuprous oxide films. At high electric voltage in the as-deposited state of Au/Cu 2O/Au-Pd cell structure, the conduction behavior follows Poole-Frenkel emission. Various parameters, such as the compliance current, the cuprous oxide microstructure, the cuprous oxide thickness, top electrode area, and top electrode material, affect the resistance switching characteristics. The required FORMING voltage is higher for Au/Cu2O/Al cell compared with the Au/Cu2O/Pt which is related to the Schottky behavior of Al contact with Cu2O. Cu2O nanowires in Au-Pt/ Cu 2O/Au-Pt cell also show resistance switching behavior, indicating scalable potential of this cell for usage as RRAM. After an initial FORMING process under an electric field of 3 x 106 V/m, the Cu2O nanowire is switched to the LRS. During the FORMING process physical damages are observed in the cell, which may be caused by Joule heating and gas evolution.

  10. CREEP BEHAVIOR OF TWO KINDS OF HR3C HEAT RESISTANT STEELS BASED ON STRESS RELAXATION TESTS%应力松弛方法研究2种HR3C耐热钢的高温蠕变行为

    Institute of Scientific and Technical Information of China (English)

    曹铁山; 方旭东; 程从前; 赵杰

    2014-01-01

    Rupture life is a main property for a material using at high-temperature condition.Usually,the rupture life is gained from creep rupture test.As creep and stress relaxation are two main behaviors for a material served in high-temperature environment,it is important to work out the interrelationship through which one of the two behaviors can be deduced from the other one.Recently,a number of researchs have taken stress relaxation test to replace creep rupture test on studying the creep behavior,and furthermore predicting the rupture life and the stress relaxation test is proved to be superior to the traditional creep rupture test for its short time,small at damage,abundant of information and so on.In this work,the stress relaxation test was used to analyze the creep behavior of two HR3C heat resistant steels with different grain sizes.Additionally,considering the change of microstructure during serve period,the aged HR3C steel was used to compare with as-received HR3C steel for studying the aging effects on the creep behavior.Furthermore,the creep behavior was correlated to their microstructure characteristics.The result was shown that the creep behaviors of two HR3C heat resistant steels varied significantly in spite of their similarity in chemical composition.The coarse grained HR3C steel had lower creep rate,larger stress exponent,greater activation energy and higher creep resistance than that of fine grained HR3C steel for both as-received one and aged one.The long-term aging process damaged the microstructures of two HR3C steels,increased aged HR3C steel's creep rate,lowered stress exponent and activation energy and reduced creep resistance.And the damaging effects on the coarse grained HR3C steel were larger than that on fine grained HR3C steel,which meant the coarse grained HR3C steel had much more stable creep resistance than that of fine grained HR3C steel.%采用应力松弛方法研究了2种不同晶粒大小HR3C耐热钢的初始态试样和时效态

  11. Verbal behavior

    OpenAIRE

    Michael, Jack

    1984-01-01

    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.

  12. Insulin Resistance

    DEFF Research Database (Denmark)

    Jensen, Benjamin Anderschou Holbech

    Insulin resistance (IR) is escalating with alarming pace and is no longer restricted to westernized countries. As a forerunner for some of the most serious threats to human health including metabolic syndrome, cardiovascular diseases, and type 2-diabetes, the need for new treatment modalities...... interventions. We further show that improving the inflammatory toning, using fish oil as fat source, protects mice against diet induced obesity and -inflammation while preserving insulin sensitivity, even in the absence of free fatty acid receptor 4. Conversely, HFD-induced intestinal dysbiosis is associated...

  13. Periodic behaviors

    CERN Document Server

    Napp, Diego; Shankar, Shiva

    2010-01-01

    This paper studies behaviors that are defined on a torus, or equivalently, behaviors defined in spaces of periodic functions, and establishes their basic properties analogous to classical results of Malgrange, Palamodov, Oberst et al. for behaviors on R^n. These properties - in particular the Nullstellensatz describing the Willems closure - are closely related to integral and rational points on affine algebraic varieties.

  14. PERIODIC BEHAVIORS

    NARCIS (Netherlands)

    Napp, Diego; Put, Marius van der; Shankar, Shiva

    2010-01-01

    This paper studies behaviors that are defined on a torus, or equivalently, behaviors defined in spaces of periodic functions, and establishes their basic properties analogous to classical results of Malgrange, Palamodov, Oberst et al. for behaviors on R(n). These properties-in particular the Nullste

  15. Behaviorally Speaking.

    Science.gov (United States)

    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)

  16. Comportamento da flexibilidade após 10 semanas de treinamento com pesos Comportamiento de la flexibilidad después de 10 semanas de entrenamiento con pesos Flexibility behavior after 10 weeks of resistance training

    Directory of Open Access Journals (Sweden)

    Edilson Serpeloni Cyrino

    2004-08-01

    flexibilidad. ANOVA y ANCOVA para medidas repetidas, seguidas por el test post hoc de Tukey, cuando P The objective of this study was to analyze the flexibility behavior of different articulations after 10 weeks of resistance training (RT. That is why, 16 inactive men (23.0 ± 2.1 years; 68.0 ± 7.0 kg; 178.8 ± 8.7 cm apparently healthy were randomly divided into training group (TG, n = 8 and control group (CG, n = 8. The group TG was submitted to 10 consecutive weeks of RT (three weekly sessions in alternated days, whereas for group CG, no systematized program of physical activities was developed in this period. The 11 exercised that composed the RT program were performed in three series of 8-12 RM. The shoulder flexion and extension, trunk flexion, lateral flexion and extension, hip extension and flexion, elbow extension and flexion and knee flexion were used for the analysis of the flexibility behavior. The ANOVA and ANCOVA for repeated measures, followed by the Tukey post hoc test for P < 0.05 were used for data treatment. Significant increase on flexibility between pre and post experiment were found in TG in shoulder flexion movements (right hemisphere, P < 0.05, hip extension (left hemisphere, P < 0.05, trunk extension (P < 0.05, trunk flexion (P < 0.05 and trunk lateral flexion (right hemisphere, P < 0.05; left hemisphere, P < 0.01. Although, the effect of the interaction group vs time was only identified in elbow flexion movements (right and left hemisphere, P < 0.05, hip extension (left hemisphere, P < 0.05 and trunk lateral flexion (left hemisphere, P < 0.01. Thus, the results of the present study suggest that the 10 first weeks of RT practice may contribute effectively for the maintenance or improvement of the flexibility levels observed in the pre-training period, in different articulations.

  17. Multilevel Resistance Programming in Conductive Bridge Resistive Memory

    Science.gov (United States)

    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.

  18. Extinction, relapse, and behavioral momentum.

    Science.gov (United States)

    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.

  19. Toward an integrative perspective on resistance to change.

    Science.gov (United States)

    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.

  20. 不同组成 Al2O3-Cr2O3砖的抗熔融还原炼铁渣行为研究%Study on melt reduction slag resistance behavior of Al2O3-Cr2O3 bricks with different compositions

    Institute of Scientific and Technical Information of China (English)

    李鹏涛; 孙红刚; 李坚强; 闫双志; 杜一昊

    2016-01-01

    In order to research the slag resistance of Al2 O3-Cr2 O3 bricks for HIsmelt process slag,commer-cial Al2 O3-Cr2 O3 bricks with 10%,30%,60%,and 90%(by mass,the same hereinafter)Cr2 O3 were select-ed,respectively (specimens numbered sequentially as Cr10,Cr30,Cr60,Cr90).The slag resistance and thermal shock resistance of specimens were evaluated by simulating the slag resistance behavior of refrac-tories in SRV melting reduction furnace basing on the rotary slag test in GB /T 8931—2007 (keep the tem-perature fluctuation of 200 -1 600 ℃ for the slag resistance test).The results show that Cr10,Cr30,Cr60, Cr90 bricks perform excellent slag resistance and thermal shock resistance;Cr10,Cr30 and Cr90 bricks perform poor slag penetration resistance,Cr60 brick has the best slag penetration resistance.Al2 O3-Cr2 O3 bricks react with MgO and FeO in slag forming a dense composite spinel layer,improving the slag corro-sion resistance of bricks.The Cr2 O3 content in matrix is a key factor to the slag corrosion resistance of specimens.The composition,structure and the reaction degree of the solid solution in the slag penetration layer are the main factors influencing the thermal shock resistance of Al2 O3-Cr2 O3 bricks.%为了研究 Al2 O3-Cr2 O3砖对熔融还原炼铁(HIsmelt 工艺)渣的抗渣性,选取市售 Cr2 O3含量(w)分别约为10%、30%、60%和90%的 Al2 O3-Cr2 O3砖(试样编号依次为 Cr10、Cr30、Cr60和 Cr90),模拟 SRV 熔融还原炉中耐火材料的抗渣行为,在 GB /T 8931—2007的回转渣蚀法试验基础上,人为制造200~1600℃的温度波动进行抗渣性试验,以综合评价材料的抗渣性和抗热震性。结果表明:Cr10、Cr30、Cr60和 Cr90砖的抗渣侵蚀性能和抗热震性能均优异,而 Cr10、Cr30和 Cr90砖的抗渣渗透性差,Cr60砖的抗渣渗透性好;Al2 O3-Cr2 O3砖与渣中MgO、FeO 反应形成了致密的复合尖晶石层,提高了材料

  1. Making Behavioral Activation More Behavioral

    Science.gov (United States)

    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. Resistance welding

    DEFF Research Database (Denmark)

    Bay, Niels; Zhang, Wenqi; Rasmussen, Mogens H.

    2003-01-01

    Resistance welding comprises not only the well known spot welding process but also more complex projection welding operations, where excessive plastic deformation of the weld point may occur. This enables the production of complex geometries and material combinations, which are often not possible...... to weld by traditional spot welding operations. Such joining processes are, however, not simple to develop due to the large number of parameters involved. Development has traditionally been carried out by large experimental investigations, but the development of a numerical programme system has changed...... this enabling prediction of the welding performance in details. The paper describes the programme in short and gives examples on industrial applications. Finally investigations of causes for failure in a complex industrial joint of two dissimilar metals are carried out combining numerical modelling...

  3. Psychological behaviorism and behaviorizing psychology.

    Science.gov (United States)

    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.

  4. Teleological behaviorism.

    Science.gov (United States)

    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.

  5. Effects of short-time heat treatment and subsequent chemical surface treatment on the mechanical properties, low-cycle fatigue behavior and corrosion resistance of a Ni-Ti (50.9 at.% Ni) biomedical alloy wire used for the manufacture of stents

    Energy Technology Data Exchange (ETDEWEB)

    Vojtech, D., E-mail: Dalibor.Vojtech@vscht.cz [Department of Metals and Corrosion Engineering, Institute of Chemical Technology, Prague, Technicka 5, 166 28 Prague 6 (Czech Republic); Voderova, M.; Kubasek, J.; Novak, P.; Seda, P.; Michalcova, A.; Fojt, J. [Department of Metals and Corrosion Engineering, Institute of Chemical Technology, Prague, Technicka 5, 166 28 Prague 6 (Czech Republic); Hanus, J. [Department of Medical Biophysics, Charles University - Faculty of Medicine in Hradec Kralove, Simkova 870, 500 38 Hradec Kralove (Czech Republic); Mestek, O. [Department of Analytical Chemistry, Institute of Chemical Technology, Prague, Technicka 5, 166 28 Prague 6 (Czech Republic)

    2011-01-25

    Research highlights: {yields} Effect of short-time heat treatments on functional properties of a NiTi alloy. {yields} Negative effect of heat treatments on corrosion resistance. {yields} Positive effect of heat treatments on fatigue life. {yields} Positive influence of chemical treatment on both fatigue and corrosion resistance. - Abstract: Cold-drawn and straight-annealed NiTi wires (50.9% Ni) with a tensile strength of 1650 MPa were subjected to heat treatments at 450, 510 and 600 deg. C for 10 min in air to simulate the shape-setting process in the manufacture of stents. Afterwards, the wires were chemically etched in acidic baths containing HF, HNO{sub 3} and H{sub 2}O, followed by boiling in water. Variations in the internal structure, surface state and chemistry and transformation behavior of the wires due to these treatments were examined in detail by scanning and transmission electron microscopy, energy dispersion spectrometry, glow discharge spectrometry, X-ray photoelectron spectroscopy and differential scanning calorimetry. Mechanical properties were determined by tensile tests, and low-cycle fatigue behavior was measured by bend-type cyclic loading tests. Corrosion behavior was assessed by immersion tests and potentiodynamic measurements. A high tensile strength of the wire was shown to be attributable to a very fine-grained structure and work hardening. Heat treatment at 450-510 deg. C/10 min did not significantly affect the tensile strength of the wire. At 600 deg. C/10 min, the strength decreased by about 600 MPa due to recrystallization. The transformation temperatures first slightly increased after heat treatment at 450 deg. C and then reduced after treatments at higher temperatures due to changes in the composition of the B2 phase. The fatigue life was observed to prolong with both heat treatment and chemical etching. In contrast, the corrosion resistance worsened with heat treatment, but it improved significantly upon chemical etching. The

  6. Behavioral Momentum Theory: Equations and Applications

    Science.gov (United States)

    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…

  7. Mechanisms of drug resistance: quinolone resistance.

    Science.gov (United States)

    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.

  8. Aggressive behavior

    NARCIS (Netherlands)

    Didden, H.C.M.; Lindsay, W.R.; Lang, R.; Sigafoos, J.; Deb, S.; Wiersma, J.; Peters-Scheffer, N.C.; Marschik, P.B.; O’Reilly, M.F.; Lancioni, G.E.

    2016-01-01

    Aggressive behavior is common in individuals with intellectual and developmental disabilities (IDDs), and it is most often targeted for intervention. Psychological, contextual, and biological risk factors may contribute to the risk of aggressive behavior. Risk factors are gender (males), level of ID

  9. Behavioral economics.

    Science.gov (United States)

    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.

  10. Animation of Antimicrobial Resistance

    Medline Plus

    Full Text Available ... Veterinary Home Animal & Veterinary Safety & Health Antimicrobial Resistance Animation of Antimicrobial Resistance Share Tweet Linkedin Pin it ... Veterinary Medicine is cited as the corporate author. Animation Animation of Antimicrobial Resistance (WMV - 19.2MB) 9: ...

  11. Animation of Antimicrobial Resistance

    Science.gov (United States)

    ... Veterinary Safety & Health Antimicrobial Resistance Animation of Antimicrobial Resistance Share Tweet Linkedin Pin it More sharing options ... produced a nine-minute animation explaining how antimicrobial resistance both emerges and proliferates among bacteria. Over time, ...

  12. Behaviorally inadequate

    DEFF Research Database (Denmark)

    Kasperbauer, Tyler Joshua

    2014-01-01

    According to situationism in psychology, behavior is primarily influenced by external situational factors rather than internal traits or motivations such as virtues. Environmental ethicists wish to promote pro-environmental behaviors capable of providing adequate protection for the environment......, but situationist critiques suggest that character traits, and environmental virtues, are not as behaviorally robust as is typically supposed. Their views present a dilemma. Because ethicists cannot rely on virtues to produce pro-environmental behaviors, the only real way of salvaging environmental virtue theory...... positive results. However, because endorsing behaviorally ineffective virtues, for whatever reason, entails that environmental ethicists are abandoning the goal of helping and protecting the environment, environmental ethicists should consider looking elsewhere than virtues and focus instead on the role...

  13. Electronic Monitoring of Feeding and Oviposition Behavior of Rice Planthoppers and Its Application in Plant Resistance Study%电子记录稻飞虱取食和产卵行为及其在植物抗虫性研究中的应用

    Institute of Scientific and Technical Information of China (English)

    服部诚

    2003-01-01

    采用AC型电子记录系统(EMS)对褐飞虱在非寄主植物稗草和具有抗性基因bph4的水稻品种Babawee上的取食行为进行了比较研究.结果表明,褐飞虱口针到达稗草韧皮部以前停止取食,这揭示了在稗草非韧皮部组织中存在拒食剂.而在抗虫品种上,口针到达韧皮部以后取食行为终止.因此,可以清楚地识别两类具有不同抑制取食抗性因子的抗性植物.分析白背飞虱产卵行为的电子记录表明,在大多数情况下,就旺盛生长的水稻植株的下半部分而言,白背飞虱产卵器插入植物组织中但不产卵.这表明旺盛生长的植株能诱导白背飞虱的产卵行为,但由于某些拒避性因素使整个产卵过程不能完成.因此,这一系统可以有效地识别具有产卵抗性的植物上行为序列中受到破坏的步骤.%Feeding behaviors of Nilaparvata lugens on a non-host plant, the barnyard grass Echinochloa crus-galli var. Oryzicola, and resistant rice Babawee (bph4) were compared by using AC-eletronic monitoring system (EMS). Waveform data obtained by EMS showed that N. Lugens usually stopped feeding activities before stylets reach the phloem in barnyard grass which revealed to contain an antifeedant in the non-phloem, whereas feeding was interrupted after stylets reached the phloem in resistant rice. Thus, EMS analysis clearly distinguished two types of resistant plants with different resistant factors against planthopper feeding. EMS analysis of Sogatella furcifera oviposition behavior on the lower part of the leaf sheath of fully-grown rice demonstrated that in most cases the ovipositor was inserted into the plant but pulled out without depositing any eggs. It suggested that oviposition behavior itself was normally induced on the fully-grown rice, but the entire process was not completed due to some deterring factors. Thus, this system is also effective in identifying a disrupted step in the behavioral sequence on a plant resistant

  14. Resistance to antibiotics

    OpenAIRE

    1999-01-01

    The antibiotics represent the most important therapeutic arsenal in the fight against pathogen microorganisms. Even in the beginning of their use, there was registered bacterial resistance, phenomenon thatbecame an alarming subject in the last decades. There are some types of resistance to antibiotics that are influenced by many factors. The resistance term can be used as microbiological resistance and clinical resistance. The resistance to antibiotics can be a natural phenomenon or a gained ...

  15. A gestalt-experiential perspective on resistance.

    Science.gov (United States)

    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.

  16. Animation of Antimicrobial Resistance

    Medline Plus

    Full Text Available ... More in Antimicrobial Resistance National Antimicrobial Resistance Monitoring ... Note: If you need help accessing information in different file formats, see Instructions for Downloading ...

  17. Animation of Antimicrobial Resistance

    Medline Plus

    Full Text Available ... Resistance National Antimicrobial Resistance Monitoring System 2014 NARMS ... Note: If you need help accessing information in different file formats, see Instructions for Downloading ...

  18. Cost Behavior

    DEFF Research Database (Denmark)

    Hoffmann, Kira

    The objective of this dissertation is to investigate determinants and consequences of asymmetric cost behavior. Asymmetric cost behavior arises if the change in costs is different for increases in activity compared to equivalent decreases in activity. In this case, costs are termed “sticky......” if the change is less when activity falls than when activity rises, whereas costs are termed “anti-sticky” if the change is more when activity falls than when activity rises. Understanding such cost behavior is especially relevant for decision-makers and financial analysts that rely on accurate cost information...

  19. Antibiotic resistance in Chlamydiae.

    Science.gov (United States)

    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.

  20. Behavioral epigenetics

    OpenAIRE

    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.

    2011-01-01

    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, devel...

  1. Tuning resistance states by thickness control in an electroforming-free nanometallic complementary resistance random access memory

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Xiang; Lu, Yang; Lee, Jongho; Chen, I-Wei, E-mail: iweichen@seas.upenn.edu [Department of Materials Science and Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6272 (United States)

    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.

  2. Facts about Antibiotic Resistance

    Science.gov (United States)

    ... Cost References Español: Datos breves Facts about Antibiotic Resistance Antibiotic resistance is one of the world’s most pressing public ... antibiotic use is a key strategy to control antibiotic resistance. Antibiotic resistance in children and older adults are ...

  3. Resisting Moment Behavior of Large Diameter and Shallow Buried Bucket Foundation for Offshore Wind Turbine%海上风电大直径宽浅式筒型基础抗弯特性分析

    Institute of Scientific and Technical Information of China (English)

    刘润; 陈广思; 刘禹臣; 徐余

    2013-01-01

      风机属于高耸结构物,承受巨大的弯矩是海上风电基础区别于其他常见结构基础的重要特征。大直径宽浅式筒型基础是适应海上风电特征荷载作用的新型基础型式。筒型基础的直径、入土深度、顶盖及侧壁厚度是控制其抗弯能力的重要技术参数。结合某海上风电工程实例,采用数值分析方法,系统研究了不同尺寸特征参数对筒型基础传递及抵抗弯矩荷载的影响,揭示了弯矩荷载作用下宽浅式筒型基础的失效模式及基础转动点位置;研究了地基承载力设计中等效均质算法的合理性。研究表明:基础抗弯承载能力随筒型基础的直径及入土深度的增加而显著增长;在弯矩荷载作用下,筒周围土体出现贯通的弧形破坏面而在基础下方土体中存在曲边三角形的稳定区;对于实际工程中的上软下硬成层土地基,经等效均质化后,将导致计算得到的基础抗弯极限承载力明显偏高。%The wind turbine belongs to high-rise structure. The foundation of wind turbine must bear huge moment, which is different from other common structure foundations. The large diameter and shallow buried bucket foundation is a new foundation type which meets the requirement of the characteristic load of offshore wind turbine. The impor-tant technological parameters of bucket foundation for resisting moment are diameter, embedded depth, upper wall and lateral thickness. An offshore wind power project is taken as an example, and the impacts of the characteristic pa-rameters of different size on bucket foundation transferring and resisting moment load are systematically studied by numerical simulation. The failure mechanisms and rotating point position of bucket foundation are revealed under moment load. The rationality of equivalent homogeneous algorithm is studied in designing the bearing capacity of the foundation. Research shows that the bearing capacity of

  4. Temporal Context, Preference, and Resistance to Change

    Science.gov (United States)

    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…

  5. Scratch behaviors in polymers

    Science.gov (United States)

    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

  6. New resistivity for high-mobility quantum Hall conductors

    Science.gov (United States)

    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.

  7. Cost Behavior

    DEFF Research Database (Denmark)

    Hoffmann, Kira

    The objective of this dissertation is to investigate determinants and consequences of asymmetric cost behavior. Asymmetric cost behavior arises if the change in costs is different for increases in activity compared to equivalent decreases in activity. In this case, costs are termed “sticky......” if the change is less when activity falls than when activity rises, whereas costs are termed “anti-sticky” if the change is more when activity falls than when activity rises. Understanding such cost behavior is especially relevant for decision-makers and financial analysts that rely on accurate cost information...... to facilitate resource planning and earnings forecasting. As such, this dissertation relates to the topic of firm profitability and the interpretation of cost variability. The dissertation consists of three parts that are written in the form of separate academic papers. The following section briefly summarizes...

  8. Animal studies of addictive behavior.

    Science.gov (United States)

    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.

  9. 氯盐环境中新型合金耐蚀钢筋Cr10Mo1的钝化行为%Passive Behavior of New Alloy Corrosion Resistant Steel Cr10Mo1 in Chloride-containing Environment

    Institute of Scientific and Technical Information of China (English)

    艾志勇; 孙伟; 蒋金洋; 麻晗; 张建春; 宋丹

    2016-01-01

    应用线性极化、电化学阻抗谱与电容电位法等方法对比研究了合金耐蚀钢筋Cr10Mo1和普通碳素钢筋在预含不同浓度(0 mol·L-1、0.1 mol·L-1、0.3 mol·L-1、0.6 mol·L-1)氯盐的较低碱度(pH=12.5)模拟混凝土孔溶液中的钝化行为,利用XPS方法分析钢筋钝化膜组成结构,分析了氯盐作用下两种钢筋钝化行为变化存在差异的原因,揭示了合金耐蚀钢筋强易钝化机制。结果表明:在各氯盐浓度下,合金耐蚀钢筋均能良好致钝且钝化效果并无较大差距,而普通碳素钢筋随氯盐浓度增大钝化效果显著减弱,当氯盐超过一定浓度则几乎不钝化,甚至发生明显点蚀。Cr氧化物作为合金耐蚀钢筋钝化膜不同于普通碳素钢筋的关键成分,高浓度氯盐作用下仍可保持稳定并维持钝化膜层完整密实,从而使耐蚀钢筋呈现强易致钝特性。%Passive behaviour of alloy corrosion-resistant steel Cr10Mo1,with plain carbon steel introduced for comparison,in low alkaline (pH= 12.5)simulated concrete pore solutions with different chloride contents (0 mol·L-1 , 0.1 mol·L-1 ,0.3 mol·L-1 ,0.6 mol·L-1 ),was evaluated by various electrochemical techniques (linear polariza-tion resistance,electrochemical impedance spectroscopy and capacitance measurements).XPS was used to determine the chemical composition of passive films formed on the steels.The reasons for differences of the passivation evolution between the two steels under the action of chloride was analyzed,and the mechanisms of strong passivation behavior of the alloy corrosion-resistant steel was revealed.The results show that the alloy corrosion-resistant steel has good and almost similar passivity in solutions with different chloride concentration,while plain carbon steel has a signi-ficant de-crease in passivity with the increasing chloride concentration.Passivation can hardly occure and pits appear when chlo

  10. Discounting Behavior

    DEFF Research Database (Denmark)

    Andersen, Steffen; Harrison, Glenn W.; Lau, Morten

    2014-01-01

    We re-evaluate the theory, experimental design and econometrics behind claims that individuals exhibit non-constant discounting behavior. Theory points to the importance of controlling for the non-linearity of the utility function of individuals, since the discount rate is defined over time......-dated utility flows and not flows of money. It also points to a menagerie of functional forms to characterize different types of non-constant discounting behavior. The implied experimental design calls for individuals to undertake several tasks to allow us to identify these models, and to several treatments...

  11. Animal Studies of Addictive Behavior

    OpenAIRE

    Vanderschuren, Louk J.M.J.; 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...

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

    Science.gov (United States)

    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.

  13. Behavior Modification

    Science.gov (United States)

    Boardman, Randolph M.

    2010-01-01

    In a perfect world, students would never talk back to school staff and never argue or fight with each other. They would complete all their assigned tasks, and disciplinary actions never would be needed. Unfortunately, people don't live in a perfect world. Student behavior is a daily concern. Teachers continue to refer students to the office as a…

  14. Behavior subtraction

    Science.gov (United States)

    Jodoin, Pierre-Marc; Saligrama, Venkatesh; Konrad, Janusz

    2008-01-01

    Network video cameras, invented in the last decade or so, permit today pervasive, wide-area visual surveillance. However, due to the vast amounts of visual data that such cameras produce human-operator monitoring is not possible and automatic algorithms are needed. One monitoring task of particular interest is the detection of suspicious behavior, i.e., identification of individuals or objects whose behavior differs from behavior usually observed. Many methods based on object path analysis have been developed to date (motion detection followed by tracking and inferencing) but they are sensitive to motion detection and tracking errors and are also computationally complex. We propose a new surveillance method capable of abnormal behavior detection without explicit estimation of object paths. Our method is based on a simple model of video dynamics. We propose one practical implementation of this general model via temporal aggregation of motion detection labels. Our method requires little processing power and memory, is robust to motion segmentation errors, and general enough to monitor humans, cars or any other moving objects in uncluttered as well as highly-cluttered scenes. Furthermore, on account of its simplicity, our method can provide performance guarantees. It is also robust in harsh environments (jittery cameras, rain/snow/fog).

  15. Resistive MHD jet simulations with large resistivity

    CERN Document Server

    Cemeljic, Miljenko; Vlahakis, Nektarios; Tsinganos, Kanaris

    2009-01-01

    Axisymmetric resistive MHD simulations for radially self-similar initial conditions are performed, using the NIRVANA code. The magnetic diffusivity could occur in outflows above an accretion disk, being transferred from the underlying disk into the disk corona by MHD turbulence (anomalous turbulent diffusivity), or as a result of ambipolar diffusion in partially ionized flows. We introduce, in addition to the classical magnetic Reynolds number Rm, which measures the importance of resistive effects in the induction equation, a new number Rb, which measures the importance of the resistive effects in the energy equation. We find two distinct regimes of solutions in our simulations. One is the low-resistivity regime, in which results do not differ much from ideal-MHD solutions. In the high-resistivity regime, results seem to show some periodicity in time-evolution, and depart significantly from the ideal-MHD case. Whether this departure is caused by numerical or physical reasons is of considerable interest for nu...

  16. Corrosion resistance of high-performance materials titanium, tantalum, zirconium

    CERN Document Server

    2012-01-01

    Corrosion resistance is the property of a material to resist corrosion attack in a particular aggressive environment. Although titanium, tantalum and zirconium are not noble metals, they are the best choice whenever high corrosion resistance is required. The exceptionally good corrosion resistance of these high–performance metals and their alloys results from the formation of a very stable, dense, highly adherent, and self–healing protective oxide film on the metal surface. This naturally occurring oxide layer prevents chemical attack of the underlying metal surface. This behavior also means, however, that high corrosion resistance can be expected only under neutral or oxidizing conditions. Under reducing conditions, a lower resistance must be reckoned with. Only very few inorganic and organic substances are able to attack titanium, tantalum or zirconium at ambient temperature. As the extraordinary corrosion resistance is coupled with an excellent formability and weldability these materials are very valua...

  17. Testing and Modeling of Contact Problems in Resistance Welding

    DEFF Research Database (Denmark)

    Song, Quanfeng

    As a part of the efforts towards a professional and reliable numerical tool for resistance welding engineers, this Ph.D. project is dedicated to refining the numerical models related to the interface behavior. An FE algorithm for the contact problems in resistance welding has been developed...... together two or three cylindrical parts as well as disc-ring pairs of dissimilar metals. The tests have demonstrated the effectiveness of the model. A theoretical and experimental study is performed on the contact resistance aiming at a more reliable model for numerical simulation of resistance welding....... The model currently employed is evaluated. It is found that the model may underestimate the constriction resistance because it is based on the assumption of continual contact area. A new model is proposed on the constriction resistance in resistance welding. A parametric study is performed on the contact...

  18. EFECTO EN LA RESISTENCIA DE LAS ESCORIAS DE FUNDICIÓN DE COBRE COMO AGREGADO FINO EN EL COMPORTAMIENTO RESISTENTE DEL HORMIGÓN EFFECT OF SMELTING COPPER SLAG AS FINE AGGREGATE ON THE RESISTANT BEHAVIOR OF CONCRETE

    Directory of Open Access Journals (Sweden)

    Patricio Cendoya

    2009-04-01

    Full Text Available Las escorias de fundición de cobre son residuos industriales provenientes de la fundición del cobre las cuales procesadas en forma de granallas y sometidas a un proceso de molienda adquieren características similares a las de un árido fino. La presente investigación estudia la influencia que tiene su incorporación en el comportamiento mecánico a flexotracción y compresión en hormigones que emplean como árido fino una combinación de arenas del río Bío-Bío con proporciones de 25%, 40% y 50% en volumen de escorias de fundición de cobre. El árido fino resultante se utiliza en la confección de hormigones dosificados para relaciones de agua cemento de 0,45 y 0,52 asociadas a resistencias especificadas a la flexotracción de 3,6 y 4,3 MPa. Se mide la trabajabilidad en el hormigón fresco, la densidad, la carga de rotura por flexotracción y la carga de rotura por compresión en el hormigón endurecido comparando los resultados con un hormigón de referencia que no contiene escorias. Los resultados señalan que la docilidad de la mezcla se incrementa debido a la textura lisa de las escorias, se produce un aumento de la densidad del hormigón endurecido y las resistencias tanto a flexotracción como compresión se incrementan en función del contenido de escorias de fundición de cobre utilizado en la mezcla.Copper slag is a by product of the copper smelting industry. We took granulated copper slag and milled it until it acquired characteristics similar to those of a fine aggregate, which was then incorporated into concrete, in combination with Bio-Bio river sand in proportions of 25%, 40% and 50% by volume of copper slag. We then examined the impact of the different combinations on the mechanical behaviour to flexotraction and compression in the resulting concrete. Our specification was to produce concrete for water-cement ratios of 0,45 and 0,52 associated to breakage resistances to flexotraction of 3.6 and 4.3 MPa, respectively. We

  19. Cell shunt resistance and photovoltaic module performance

    Energy Technology Data Exchange (ETDEWEB)

    McMahon, T.J.; Basso, T.S.; Rummel, S.R. [National Renewable Energy Lab., Golden, CO (United States)

    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. Animation of Antimicrobial Resistance

    Medline Plus

    Full Text Available ... how antimicrobial resistance both emerges and proliferates among bacteria. Over time, the use of antimicrobial drugs will result in the development of resistant strains of bacteria, complicating clinician's efforts to select the appropriate antimicrobial ...

  1. Behavioral Momentum and Relapse of Extinguished Operant Responding

    OpenAIRE

    Podlesnik, Christopher A; Shahan, Timothy A

    2009-01-01

    Previous experiments on behavioral momentum have shown that relative resistance to extinction of operant behavior in the presence of a stimulus depends on the rate of reinforcement associated with that stimulus, even if some of those reinforcers occur independently of the behavior. We present three experiments examining whether the rate of reinforcement in the presence of a stimulus similarly modulates the relative relapse of operant behavior produced by reinstatement, resurgence, and renewal...

  2. Reinforcement context and resistance to change.

    Science.gov (United States)

    Grace, Randolph C.; McLean, Anthony P.; Nevin, John A.

    2003-08-29

    Eight pigeons responded in a multiple variable-interval (VI) schedule in which a constant component always delivered 40rft/h, and an alternated component was either rich (200rft/h) or lean (6.67rft/h) in different conditions. Four tests of resistance to change were conducted in each condition: prefeeding, full extinction, constant-component-only extinction, and response-independent food. Resistance to both prefeeding and full extinction in the constant component varied inversely with the reinforcement rate in the alternated component, but resistance to response-independent food did not. The extinction and response-independent food results were consistent with [J. Exp. Psychol.: Anim. Behav. Proc. 25 (1999) 256] behavioral momentum model. Maintaining reinforcement in the alternated component increased resistance to extinction in the constant component, as predicted by the behavioral momentum model but not accounts of multiple-schedule performance based on [J. Exp. Anal. Behav. 13 (1970) 243] equation. Overall, the momentum model gave a good account of the results with the exception of the prefeeding data. Possible ways to reconcile the prefeeding results with behavioral momentum theory are considered.

  3. Behavioral factors.

    Science.gov (United States)

    Zero, D T; Lussi, A

    2006-01-01

    During and after an erosive challenge, behavioral factors play a role in modifying the extent of erosive tooth wear. The manner that dietary acids are introduced into the mouth (gulping, sipping, use of a straw) will affect how long the teeth are in contact with the erosive challenge. The frequency and duration of exposure to an erosive agent is of paramount importance. Night-time exposure (e.g. baby bottle-feeding) to erosive agents may be particularly destructive because of the absence of salivary flow. Health-conscious individuals tend to ingest acidic drinks and juices more frequently and tend to have higher than average oral hygiene. While good oral hygiene is of proven value in the prevention of periodontal disease and dental caries, frequent toothbrushing with abrasive oral hygiene products may enhance erosive tooth wear. Unhealthy lifestyles such as consumption of designer drugs, alcopops and alcohol abuse are other important behavioral factors.

  4. Resisting Mind Control.

    Science.gov (United States)

    Anderson, Susan M.; Zimbardo, Philip G.

    1980-01-01

    Provides conceptual analyses of mind control techniques along with practical advice on how to resist these techniques. The authors stress that effective mind control stems more from everyday social relations than from exotic technological gimmicks. Suggestions are given for resisting persuasion, resisting systems, and challenging the system.…

  5. Effective graph resistance

    NARCIS (Netherlands)

    Ellens, W.; Spieksma, F.M.; Mieghem, P. van; Jamakovic, A.; Kooij, R.E.

    2011-01-01

    This paper studies an interesting graph measure that we call the effective graph resistance. The notion of effective graph resistance is derived from the field of electric circuit analysis where it is defined as the accumulated effective resistance between all pairs of vertices. The objective of the

  6. Overcoming resistance to change.

    Science.gov (United States)

    McKay, L

    1993-01-01

    The pace of change in health care organizations challenges nursing administrators at all levels of management to be effective change agents. As resistance is an inevitable element in the process of planned change, inclusion of interventions to overcome resistance is critical to the change agent role. The author presents five theoretically-based strategies for reducing the levels of resistance to planned change.

  7. CONSUMER BEHAVIOR

    OpenAIRE

    Ilie BUDICA; Silvia PUIU; Bogdan Andrei BUDICA

    2010-01-01

    The study of consumers helps firms and organizations improve their marketing strategies by understanding issues such as: the psychology of how consumers think, feel, reason, and select between different alternatives; the psychology of how the consumer is influenced by his or her environment; the behavior of consumers while shopping or making other marketing decisions; limitations in consumer knowledge or information processing abilities influence decisions and marke...

  8. Exact Evaluation of The Resistance in an Infinite Face- Centered Cubic Network

    CERN Document Server

    Asad, Jihad H

    2012-01-01

    The equivalent resistance between the origin and the lattice site (2n,0,0), in an infinite Face Centered Cubic network consisting from identical resistors each of resistance R, has been expressed in terms of the complete elliptic integral of the first kind, and . The asymptotic behavior is investigated, and some numerical values for the equivalent resistance are presented.

  9. OPEC behavior

    Science.gov (United States)

    Yang, Bo

    This thesis aims to contribute to a further understanding of the real dynamics of OPEC production behavior and its impacts on the world oil market. A literature review in this area shows that the existing studies on OPEC still have some major deficiencies in theoretical interpretation and empirical estimation technique. After a brief background review in chapter 1, chapter 2 tests Griffin's market-sharing cartel model on the post-Griffin time horizon with a simultaneous system of equations, and an innovative hypothesis of OPEC's behavior (Saudi Arabia in particular) is then proposed based on the estimation results. Chapter 3 first provides a conceptual analysis of OPEC behavior under the framework of non-cooperative collusion with imperfect information. An empirical model is then constructed and estimated. The results of the empirical studies in this thesis strongly support the hypothesis that OPEC has operated as a market-sharing cartel since the early 1980s. In addition, the results also provide some support of the theory of non-cooperative collusion under imperfect information. OPEC members collude under normal circumstances and behave competitively at times in response to imperfect market signals of cartel compliance and some internal attributes. Periodic joint competition conduct plays an important role in sustaining the collusion in the long run. Saudi Arabia acts as the leader of the cartel, accommodating intermediate unfavorable market development and punishing others with a tit-for-tat strategy in extreme circumstances.

  10. Corrosion-Resistant High-Entropy Alloys: A Review

    Directory of Open Access Journals (Sweden)

    Yunzhu Shi

    2017-02-01

    Full Text Available Corrosion destroys more than three percent of the world’s gross domestic product. Therefore, the design of highly corrosion-resistant materials is urgently needed. By breaking the classical alloy-design philosophy, high-entropy alloys (HEAs possess unique microstructures, which are solid solutions with random arrangements of multiple elements. The particular locally-disordered chemical environment is expected to lead to unique corrosion-resistant properties. In this review, the studies of the corrosion-resistant HEAs during the last decade are summarized. The corrosion-resistant properties of HEAs in various aqueous environments and the corrosion behavior of HEA coatings are presented. The effects of environments, alloying elements, and processing methods on the corrosion resistance are analyzed in detail. Furthermore, the possible directions of future work regarding the corrosion behavior of HEAs are suggested.

  11. Adhesion Control between Resist and Photomask Blank

    Science.gov (United States)

    Kurihara, Masaaki; Hatakeyama, Sho; Yoshida, Kouji; Abe, Makoto; Totsukawa, Daisuke; Morikawa, Yasutaka; Mohri, Hiroshi; Hoga, Morihisa; Hayashi, Naoya; Ohtani, Hiroyuki; Fujihira, Masamichi

    2009-06-01

    Most problems in photomask fabrication such as pattern collapse, haze, and cleaning damage are related to the behavior of surfaces and interfaces of resists, opaque layers, and quartz substrates. Therefore, it is important to control the corresponding surface and interface energies in photomask fabrication processes. In particular, adhesion analysis in microscopic regions is strongly desirable to optimize material and process designs in photomask fabrication. We applied the direct peeling (DP) method with a scanning probe microscope (SPM) tip and measured the adhesion of resist patterns on Cr and quartz surfaces for photomask process optimization. We also studied the effect of tip shape on the reproducibility of adhesion measurements and the dependence of collapse behavior on the resist profile. We measured lateral forces between the resulting collapsed resist pillar and the Cr or the quartz surface before and after the sliding and related these observed lateral forces to the static and kinetic frictional forces, respectively. We also studied the effect of surface modification of the Cr and quartz surfaces with silanization reagents on adhesion measured with the DP method. Resist adhesion could be controlled by surface modification using silanes. We also discuss the relationship between the adhesion observed with the DP method and the properties of the modified surfaces including water contact angles and local adhesive forces measured from force-distance curves with an SPM.

  12. Evolutionary consequences of behavioral diversity

    CERN Document Server

    Stewart, Alexander J; Plotkin, Joshua B

    2016-01-01

    Iterated games provide a framework to describe social interactions among groups of individuals. Recent work stimulated by the discovery of "zero-determinant" strategies has rapidly expanded our ability to analyze such interactions. This body of work has primarily focused on games in which players face a simple binary choice, to "cooperate" or "defect". Real individuals, however, often 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 finite populations. We show that, in public goods games, some two-choice strategies can nonetheless resist invasion by all possible multi-choice invaders, even while engaging in relatively little punishment. We also show that access to greater behavioral choice results in more "rugged " fitness landscapes, with populations able to stabilize cooperation at multiple levels of investment, such that choice f...

  13. A Comparison of Resistance to Extinction Following Dynamic and Static Schedules of Reinforcement

    OpenAIRE

    Craig, Andrew R.

    2013-01-01

    Resistance to extinction of single-schedule performance is negatively related to the reinforcer rate that an organism experienced in the pre-extinction context. This finding opposes the predications of behavioral momentum theory, which states that resistance to change, in general, is positively related to reinforcer rates. The quantitative model of extinction provided by behavioral momentum theory can describe resistance to extinction following single schedules in a post-hoc fashion, and only...

  14. Resisting Organizational Change

    Directory of Open Access Journals (Sweden)

    Gunnar Andersson

    2015-03-01

    Full Text Available We are continuously reminded of how change induces controversy and resistance, regardless of support. We repeatedly experience resistance in difficulties of implementation, little progress, and poor results, rather than increased productivity as anticipated. In a detailed account of how change plays out, a mosaic of what resistance looks like emerges. The picture is both familiar and absolutely concrete, and challenges the structural assumptions and dichotomies on support and resistance in an organization. The findings invite technologies, people, actions, practices and materiality to the discussions on support and resistance.

  15. Multidrug resistance associated proteins in multidrug resistance

    OpenAIRE

    Sodani, Kamlesh; Patel, Atish; Kathawala, Rishil J.; Chen, Zhe-Sheng

    2012-01-01

    Multidrug resistance proteins (MRPs) are members of the C family of a group of proteins named ATP-binding cassette (ABC) transporters. These ABC transporters together form the largest branch of proteins within the human body. The MRP family comprises of 13 members, of which MRP1 to MRP9 are the major transporters indicated to cause multidrug resistance in tumor cells by extruding anticancer drugs out of the cell. They are mainly lipophilic anionic transporters and are reported to transport fr...

  16. The resistance to change of observing.

    Science.gov (United States)

    Shahan, Timothy A; Magee, Adam; Dobberstein, Andria

    2003-11-01

    Observing responses produce contact with discriminative stimuli and have been considered analogous to attending. Many studies have examined the effects of reinforcement rate on the resistance to change of simple operant behavior, but nothing is known about the resistance to change of observing. Two experiments examined the effects of primary reinforcement rate on the resistance to change of observing behavior of pigeons. In Experiment 1, a multiple schedule of observing-response procedures was arranged. In a rich component, observing responses produced stimuli correlated with a high rate of random-interval (RI) reinforcement or extinction. In a lean component, observing responses produced stimuli correlated with a lower rate of RI reinforcement or extinction. In both components, observing responses produced the multiple-schedule stimuli on a fixed-interval 0.75-s schedule. In Experiment 2, a similar procedure was used, but observing in the rich and lean components produced schedule-correlated stimuli on an RI 15-s schedule. Observing in the rich component occurred at a higher rate and was more resistant to disruptions produced by presession feeding and response-independent food deliveries during intercomponent intervals. Despite more frequent observing during unsignaled periods of extinction than unsignaled periods of RI reinforcement, observing during extinction periods was less resistant to change. In addition, replicating the usual result, responding on the food key was generally more resistant to change in the presence of stimuli associated with higher reinforcement rates. These results suggest that quantitative descriptions of resistance to change derived with simple food-maintained responding may be applicable to observing, and perhaps by extension, to attending.

  17. Negative differential resistance and rectifying behavior in a carbon-based aymmetry molecular device%基于非对称分子的全碳分子器件的负微分电阻及整流行为

    Institute of Scientific and Technical Information of China (English)

    邱深玉; 万海青

    2016-01-01

    使用基于非平衡格林函数和密度泛函理论的第一性原理计算方法,研究苯环连接碳链构成的非对称分子与石墨烯电极组成的分子器件的电子输运性质。通过计算,我们发现该分子器件表现出明显的负微分电阻现象和整流行为,通过分析分子自洽哈密顿量和前线分子轨道,发现整流行为的出现是由于不同方向的外加电场导致前线分子轨道能级的非对称移动造成的,而负微分电阻是因为在某些特定电压下电导通道被压制,使得电流迅速降低而形成的。%Using thefirst-principles method,It investigated the electronic transport properties for an novel a-symmetry molecular device constructed by a phenyl ring embedding in a carbon chain between two gra-phene electrodes.Obviouslynegative differential resistance (NDR ) behavior and rectifying performance werenumerically observed in such proposed molecular device.The analysis of the molecularproj ected self-consistent Hamiltonian and the evolution of the frontier molecular orbitals (MOs)suggestedthatthe rectif-ying performance wereresulting from the asymmetry energy level shift of MOs under the differentdirection of the external electric field.But the NDR behavior came from the conduction orbital beingsuppressed at certain bias.

  18. Logical Behaviorism

    OpenAIRE

    Malcolm, Norman; Altuner, Ilyas

    2015-01-01

    The paper deals exclusively with the doctrine called ‘Logical Behaviorism’. Although this position does not vogue it enjoyed in the 1930s and 1940s, it will always possess a compelling attraction for anyone who is perplexed by the psychological concepts, who has become aware of worthlessness of an appeal to introspection as an account of how we learn those concepts, and he has no inclination to identify mind with brain. There, of course, are other forms of behaviorism, and of reductionism, wh...

  19. CONSUMER BEHAVIOR

    Directory of Open Access Journals (Sweden)

    Ilie BUDICA

    2010-03-01

    Full Text Available The study of consumers helps firms and organizations improve their marketing strategies by understanding issues such as: the psychology of how consumers think, feel, reason, and select between different alternatives; the psychology of how the consumer is influenced by his or her environment; the behavior of consumers while shopping or making other marketing decisions; limitations in consumer knowledge or information processing abilities influence decisions and marketing outcome; how consumer motivation and decision strategies differ between products that differ in their level of importance or interest that they entail for the consumer; and how marketers can adapt and improve their marketing campaigns and marketing strategies to more effectively reach the consumer.

  20. Trastuzumab Resistance: Role for Notch Signaling

    Directory of Open Access Journals (Sweden)

    Kinnari Mehta

    2009-01-01

    Full Text Available Epidermal growth factor receptor-2 (ErbB-2/HER2 is a potent breast oncogene that has been shown to be amplified in 20% of breast cancers. Overexpression of ErbB-2 predicts for aggressive tumor behavior, resistance to some cytotoxic and antihormonal therapies, and poor overall survival. Trastuzumab, the humanized, monoclonal antibody directed against ErbB-2 has shown tremendous efficacy and improved overall survival for women when combined with a taxane-based chemotherapy. However, resistance to trastuzumab remains a major concern, most notably in women with metastatic breast cancer. Numerous mechanisms that include overexpression of alternate receptor tyrosine kinases and/or loss of critical tumor suppressors have been proposed in the last several years to elucidate trastuzumab resistance. Here we review the many possible mechanisms of action that could contribute to resistance, and novel therapies to prevent or reverse the resistant phenotype. Moreover, we provide a critical role for Notch signaling cross-talk with overlapping or new signaling networks in trastuzumab-resistant breast.

  1. Combustion Synthesis TiC-A12O3/Fe FGM and its Resisting Thermal Shock Behaviors%燃烧合成TiC-A12O3/Fe梯度材料及其抗热震行为

    Institute of Scientific and Technical Information of China (English)

    张卫方; 陶春虎; 习年生; 韩杰才; 杜善义

    2001-01-01

    The microstructure and composition distribution of TiC-A12O3/Fe functionally graded materials(FGM) prepared by SHS/PHIP were studied, and the resisting thermal shock behavior was analyzed. The results show that TiC-A12Os/Fe FGM has the desired composition distribution.The thermal shock fracture of TiC-A12O3/Fe FGM originated from the surface on the side of ceramic and propagated perpendicular to the graded layer. And the crack of thermal fatigue originated and propagated in graded layer. However, no cross-section crevice through the graded layer was found in the two conditions.%采用自蔓延高温合成结合准热等静压(SHS/PHIP)制备出了具有对称结构的TiC-A12O3/Fe梯度材料,并对其抗热冲击及抗热疲劳行为进行了测试和分析。结果表明,SHS/PHIP制备的TiC-A12O3/Fe梯度材料具有预期的梯度式组成,在热冲击和热疲劳实验过程中均无梯度层间横向贯穿裂缝,克服了传统陶瓷/金属直接接合界面的热应力剥落。

  2. Wear behavior and corrosion resistance of NiCrAl/TiC composite coating on aluminum alloy by laser cladding%铝合金表面激光熔覆NiCrAl/TiC复合涂层的磨损行为和耐蚀性能

    Institute of Scientific and Technical Information of China (English)

    李琦; 刘洪喜; 张晓伟; 姚爽; 张旭

    2014-01-01

    为提高铝合金的摩擦磨损和耐蚀性能,在A390铝合金基体上通过激光熔覆制备NiCrAl/TiC复合涂层。采用XRD和EDS分析了涂层的物相组成,结合SEM观察了涂层的微观组织,运用摩擦磨损试验机和电化学工作站测试了涂层的摩擦磨损和耐腐蚀性能。结果表明:复合涂层主要物相为AlNi、Al 3 Ni 2、TiC ,同时含有少量的Cr 13 Ni 5 Si 2、Cu 9 Al 4和α(Al)。涂层自下至上分别为短棒状树枝晶、胞状晶、柱状树枝晶和等轴晶。相同磨损条件下,A390基体发生了严重的磨粒磨损和剥层磨损,而激光熔覆涂层只产生了轻微的磨粒磨损,熔覆层的相对耐磨性为3.16。在3.5%NaCl溶液中的极化曲线和电化学阻抗谱(EIS)显示:熔覆层自腐蚀电位较A390基体的正移,腐蚀电流密度减小;熔覆层呈单容抗特性,而A390基体在高频区表现为容抗特性,在中低频区则为感抗特性。在Bote图中,低频区熔覆层对应的相位角和中低频段熔覆层的阻抗模值均大于A390基体的,表明熔覆层的耐蚀性远高于A390基体的。熔覆层的腐蚀形貌为局部点蚀,A390基体的腐蚀形貌为晶间腐蚀和剥蚀。%In order to improve the frictional wear behavior and corrosion resistance of aluminum alloy, NiCrAl/TiC composite coating was fabricated on A390 aluminum alloy by laser cladding. The phase constitution, microstructure, frictional wear behavior and corrosion resistance of the composite coating were analyzed using X-ray diffraction (XRD), energy dispersive spectrum (EDS), scanning electron microscope (SEM), friction and wear testing machine and electrochemical workstation. The results show that the coating is mainly composed of AlNi, Al 3 Ni 2 and TiC phases, and a small amount of Cr13Ni5Si2, Cu9Al4 and α(Al) phases. The microstructures of the coating from the bottom to top are dendrite crystal, cellular crystal, columnar dendrite crystal and equiaxed

  3. Resistive switching effect of Ag/MoS2/FTO device

    Science.gov (United States)

    Sun, Bai; Zhao, Wenxi; Liu, Yonghong; Chen, Peng

    2015-09-01

    The electric-pulse-driven resistance change of metal/oxides/metal structure, which is called resistive switching effect, is a fascinating phenomenon for the development of next generation non-volatile memory. In this work, an outstanding bipolar resistive switching behavior of Ag/MoS2/fluorine-doped tin oxide (FTO) device is demonstrated. The device can maintain superior reversible stability over 100 cycles with an OFF/ON-state resistance ratio of about 103 at room temperature.

  4. Treatment-Resistant Schizophrenia

    DEFF Research Database (Denmark)

    Howes, Oliver D; McCutcheon, Rob; Agid, Ofer;

    2016-01-01

    OBJECTIVE: Research and clinical translation in schizophrenia is limited by inconsistent definitions of treatment resistance and response. To address this issue, the authors evaluated current approaches and then developed consensus criteria and guidelines. METHOD: A systematic review of randomized...... antipsychotic clinical trials in treatment-resistant schizophrenia was performed, and definitions of treatment resistance were extracted. Subsequently, consensus operationalized criteria were developed through 1) a multiphase, mixed methods approach, 2) identification of key criteria via an online survey, and 3...... responsive from treatment-resistant patients. CONCLUSIONS: There is considerable variation in current approaches to defining treatment resistance in schizophrenia. The authors present consensus guidelines that operationalize criteria for determining and reporting treatment resistance, adequate treatment...

  5. Challenges to Resistance Welding

    DEFF Research Database (Denmark)

    Song, Quanfeng

    This report originates from the compulsory defense during my Ph.D. study at the Technical University of Denmark. Resistance welding is an old and well-proven technology. Yet the emergence of more and more new materials, new designs, invention off new joining techniques, and more stringent...... requirement in quality have imposed challenges to the resistance welding. More some research and development have to be done to adapt the old technology to the manufacturing industry of the 21st century. In the 1st part of the report, the challenging factors to the resistance welding are reviewed. Numerical...... simulation of resistance welding has been under development for many years. Yet it is no easy to make simulation results reliable and accurate because of the complexity of resistance welding process. In the 2nd part of the report numerical modeling of resistance welding is reviewed, some critical factors...

  6. Behavior subtraction.

    Science.gov (United States)

    Jodoin, Pierre-Marc; Saligrama, Venkatesh; Konrad, Janusz

    2012-09-01

    Background subtraction has been a driving engine for many computer vision and video analytics tasks. Although its many variants exist, they all share the underlying assumption that photometric scene properties are either static or exhibit temporal stationarity. While this works in many applications, the model fails when one is interested in discovering changes in scene dynamics instead of changes in scene's photometric properties; the detection of unusual pedestrian or motor traffic patterns are but two examples. We propose a new model and computational framework that assume the dynamics of a scene, not its photometry, to be stationary, i.e., a dynamic background serves as the reference for the dynamics of an observed scene. Central to our approach is the concept of an event, which we define as short-term scene dynamics captured over a time window at a specific spatial location in the camera field of view. Unlike in our earlier work, we compute events by time-aggregating vector object descriptors that can combine multiple features, such as object size, direction of movement, speed, etc. We characterize events probabilistically, but use low-memory, low-complexity surrogates in a practical implementation. Using these surrogates amounts to behavior subtraction, a new algorithm for effective and efficient temporal anomaly detection and localization. Behavior subtraction is resilient to spurious background motion, such as due to camera jitter, and is content-blind, i.e., it works equally well on humans, cars, animals, and other objects in both uncluttered and highly cluttered scenes. Clearly, treating video as a collection of events rather than colored pixels opens new possibilities for video analytics.

  7. CMOS compatible nanoscale nonvolatile resistance switching memory.

    Science.gov (United States)

    Jo, Sung Hyun; Lu, Wei

    2008-02-01

    We report studies on a nanoscale resistance switching memory structure based on planar silicon that is fully compatible with CMOS technology in terms of both materials and processing techniques employed. These two-terminal resistance switching devices show excellent scaling potential well beyond 10 Gb/cm2 and exhibit high yield (99%), fast programming speed (5 ns), high on/off ratio (10(3)), long endurance (10(6)), retention time (5 months), and multibit capability. These key performance metrics compare favorably with other emerging nonvolatile memory techniques. Furthermore, both diode-like (rectifying) and resistor-like (nonrectifying) behaviors can be obtained in the device switching characteristics in a controlled fashion. These results suggest that the CMOS compatible, nanoscale Si-based resistance switching devices may be well suited for ultrahigh-density memory applications.

  8. Animation of Antimicrobial Resistance

    Medline Plus

    Full Text Available ... more understandable to non-scientists by showing how bacterial antimicrobial resistance can develop and spread. All FDA CVM ... Education Inspections & Compliance Federal, State & Local ...

  9. Regicide and Resistance

    DEFF Research Database (Denmark)

    Flohr, Mikkel

    2016-01-01

    This article examines the role of resistance in Michel Foucault’s political thought. The article recovers this otherwise obscured aspect of Foucault’s thought through a systematic analysis of his theoretical regicide and consequent reconceptualization of power, agency and resistance. It is argued...... that Foucault developed a highly original account of resistance, which was, and should continue to be considered, central to his thought and its critical potential. It is shown how Foucault’s concept of resistance overcomes the limitation of voluntarism and determinism, which continue to mare contemporary...

  10. Animation of Antimicrobial Resistance

    Science.gov (United States)

    ... Animal & Veterinary Cosmetics Tobacco Products Animal & ... antimicrobial resistance both emerges and proliferates among bacteria. Over time, the use of antimicrobial drugs will result in the development ...

  11. Some verbal behavior about verbal behavior

    OpenAIRE

    Salzinger, Kurt

    2003-01-01

    Beginning with behavior analysts' tendency to characterize verbal behavior as “mere” verbal behavior, the author reviews his own attempt to employ it to influence both his staff and policies of our government. He then describes its role in psychopathology, its effect on speakers in healing themselves and on engendering creativity. The paper ends by calling to our attention the role of verbal behavior in the construction of behavior analysis.

  12. Antibiotic resistance: a primer and call to action.

    Science.gov (United States)

    Smith, Rachel A; M'ikanatha, Nkuchia M; Read, Andrew F

    2015-01-01

    During the past century, discoveries of microorganisms as causes of infections and antibiotics as effective therapeutic agents have contributed to significant gains in public health in many parts of the world. Health agencies worldwide are galvanizing attention toward antibiotic resistance, which is a major threat to public health (Centers for Disease Control and Prevention, 2013; World Health Organization, 2014). Some life scientists believe that we are approaching the post-antibiotic age (Davies & Davies, 2010). The growing threat of antimicrobial resistance is fueled by complex factors with biological, behavioral, and societal aspects. This primer provides an overview of antibiotic resistance and its growing burden on public health, the biological and behavioral mechanisms that increase antibiotic resistance, and examples of where health communication scholars can contribute to efforts to make our current antibiotic drugs last as long as possible. In addition, we identify compelling challenges for current communication theories and practices.

  13. Glycosphingolipids and insulin resistance

    NARCIS (Netherlands)

    M. Langeveld; J.F.M.G. Aerts

    2009-01-01

    Obesity is associated with an increased risk for insulin resistance, a state characterized by impaired responsiveness of liver, muscle and adipose tissue to insulin. One class of lipids involved in the development of insulin resistance are the (glyco)sphingolipids. Ceramide, the most simple sphingol

  14. Animation of Antimicrobial Resistance

    Medline Plus

    Full Text Available ... CVM produced material may be copied, reproduced, and distributed as long as FDA's Center for Veterinary Medicine ... More in Antimicrobial Resistance National Antimicrobial Resistance Monitoring ... Note: If you need help accessing information in different file formats, see Instructions for Downloading ...

  15. Engineered plant virus resistance.

    Science.gov (United States)

    Galvez, Leny C; Banerjee, Joydeep; Pinar, Hasan; Mitra, Amitava

    2014-11-01

    Virus diseases are among the key limiting factors that cause significant yield loss and continuously threaten crop production. Resistant cultivars coupled with pesticide application are commonly used to circumvent these threats. One of the limitations of the reliance on resistant cultivars is the inevitable breakdown of resistance due to the multitude of variable virus populations. Similarly, chemical applications to control virus transmitting insect vectors are costly to the farmers, cause adverse health and environmental consequences, and often result in the emergence of resistant vector strains. Thus, exploiting strategies that provide durable and broad-spectrum resistance over diverse environments are of paramount importance. The development of plant gene transfer systems has allowed for the introgression of alien genes into plant genomes for novel disease control strategies, thus providing a mechanism for broadening the genetic resources available to plant breeders. Genetic engineering offers various options for introducing transgenic virus resistance into crop plants to provide a wide range of resistance to viral pathogens. This review examines the current strategies of developing virus resistant transgenic plants.

  16. Resistance to change

    NARCIS (Netherlands)

    Dow, J.; Perotti, E.

    2009-01-01

    Established firms often fail to maintain leadership following disruptive market shifts. We argue that such firms are more prone to internal resistance. A radical adjustment of assets affects the distribution of employee rents, creating winners and losers. Losers resist large changes when strong cust

  17. Resistance to change

    NARCIS (Netherlands)

    Dow, J.; Perotti, E.

    2013-01-01

    Established firms often fail to maintain leadership following disrup tive market shifts. We argue that such firms are more prone to internal resistance. A radical adjustment of assets affects the distribution of employee rents, creating winners and losers. Losers resist large changes when strong cus

  18. Animation of Antimicrobial Resistance

    Medline Plus

    Full Text Available ... Skip to common links HHS U.S. Department of Health and Human Services U.S. Food and Drug Administration ... Tobacco Products Animal & Veterinary Home Animal & Veterinary Safety & Health Antimicrobial Resistance Animation of Antimicrobial Resistance Share Tweet ...

  19. African Women Writing Resistance

    Institute of Scientific and Technical Information of China (English)

    Jennifer Browdy de Hernandez; Pauline Dongala; Omotayo; Jolaosho; Anne Serafin

    2011-01-01

    AFRICAN Women Writing Resistance is the first transnational anthology to focus on women's strategies of resistance to the challenges they face in Africa today.The anthology brings together personal narratives,testimony,interviews,short stories,poetry,performance scripts,folktales and lyrics.

  20. Antimicrobial Resistant Streptococcus pneumoniae

    Directory of Open Access Journals (Sweden)

    B Khanal

    2010-09-01

    Full Text Available Introduction: Pneumococcal infections are important cause of morbidity and mortality. Knowledge of antimicrobial susceptibility patterns plays important role in the selection of appropriate therapy. Present study was undertaken to analyze the susceptibility patterns of pneumococcal isolates against commonly used antimicrobials with special reference to determination of minimum inhibitory concentration (MIC of penicillin in a tertiary care hospital in eastern Nepal. Methods: Twenty-six strains of S. pneumoniae isolated from various clinical specimens submitted to microbiology laboratory were evaluated. All isolates were tested for antimicrobial susceptibility by disk diffusion method. MIC of penicillin was tested by broth dilution method. Results: Of the total isolates 19 (73% were from invasive infections. Seven isolates were resistant to cotrimoxazole. No resistance to penicillin was seen in disk diffusion testing. Less susceptibility to penicillin (MIC 0.1-1.0 mg/L was observed in five (17% isolates. High level resistance to penicillin was not detected. One isolate was multidrug resistant. Conclusions: S. pneumoniaeisolates with intermediate resistance to penicillin prevail in Tertiary Care Hospital in eastern Nepal, causing invasive and noninvasive infections. As intermediate resistance is not detected in routine susceptibility testing, determination of MIC is important. It helps not only in the effective management of life threatening infections but is also essential in continuous monitoring and early detection of resistance. In addition, further study on pneumococcal infections, its antimicrobial resistance profile and correlation with clinical and epidemiological features including serotypes and group prevalence is recommended in future. Keywords: antimicrobial susceptibility pattern, penicillin, Streptococcus pneumoniae.

  1. Drug resistance in malaria

    Directory of Open Access Journals (Sweden)

    S C Parija

    2011-01-01

    Full Text Available Antimalarial chemotherapy is an important component of all malaria control programmes throughout the world. This is especially so in light of the fact that there are no antimalarial vaccines which are available for clinical use at present. Emergence and spread of malaria parasites which are resistant to many of the available antimalarials today is, therefore, a major cause for concern. Till date, resistance to all groups of antimalarials excluding artemisinin has been reported. In recent years, in vitro resistance to even artemisinin has been described. While resistance to antibacterial agents has come to prominence as a clinical problem in recent years, antiparasitic resistance in general and antimalarial resistance in particular has not received much attention, especially in the Indian scenario. The present review deals with commonly used antimalarial drugs and the mechanisms of resistance to them. Various methods of detecting antimalarial resistance and avoiding the same have also been dealt with. Newer parasite targets which can be used in developing newer antimalarial agents and antimalarials obtained from plants have also been mentioned.

  2. Thermal Shock-resistant Cement

    Energy Technology Data Exchange (ETDEWEB)

    Sugama T.; Pyatina, T.; Gill, S.

    2012-02-01

    We studied the effectiveness of sodium silicate-activated Class F fly ash in improving the thermal shock resistance and in extending the onset of hydration of Secar #80 refractory cement. When the dry mix cement, consisting of Secar #80, Class F fly ash, and sodium silicate, came in contact with water, NaOH derived from the dissolution of sodium silicate preferentially reacted with Class F fly ash, rather than the #80, to dissociate silicate anions from Class F fly ash. Then, these dissociated silicate ions delayed significantly the hydration of #80 possessing a rapid setting behavior. We undertook a multiple heating -water cooling quenching-cycle test to evaluate the cement’s resistance to thermal shock. In one cycle, we heated the 200 and #61616;C-autoclaved cement at 500 and #61616;C for 24 hours, and then the heated cement was rapidly immersed in water at 25 and #61616;C. This cycle was repeated five times. The phase composition of the autoclaved #80/Class F fly ash blend cements comprised four crystalline hydration products, boehmite, katoite, hydrogrossular, and hydroxysodalite, responsible for strengthening cement. After a test of 5-cycle heat-water quenching, we observed three crystalline phase-transformations in this autoclaved cement: boehmite and #61614; and #61543;-Al2O3, katoite and #61614; calcite, and hydroxysodalite and #61614; carbonated sodalite. Among those, the hydroxysodalite and #61614; carbonated sodalite transformation not only played a pivotal role in densifying the cementitious structure and in sustaining the original compressive strength developed after autoclaving, but also offered an improved resistance of the #80 cement to thermal shock. In contrast, autoclaved Class G well cement with and without Class F fly ash and quartz flour failed this cycle test, generating multiple cracks in the cement. The major reason for such impairment was the hydration of lime derived from the dehydroxylation of portlandite formed in the autoclaved

  3. HIV resistance to raltegravir.

    Science.gov (United States)

    Clavel, Francois

    2009-11-24

    Similar to all antiretroviral drugs, failure of raltegravir-based treatment regimens to fully supress HIV replication almost invariably results in emergence of HIV resistance to this new drug. HIV resistance to raltegravir is the consequence of mutations located close to the integrase active site, which can be divided into three main evolutionary pathways: the N155H, the Q148R/H/K and the Y143R/C pathways. Each of these primary mutations can be accompanied by a variety of secondary mutations that both increase resistance and compensate for the variable loss of viral replicative capacity that is often associated with primary resistance mutations. One unique property of HIV resistance to raltegravir is that each of these different resistance pathways are mutually exclusive and appear to evolve separately on distinct viral genomes. Resistance is frequently initiated by viruses carrying mutations of the N155H pathway, followed by emergence and further dominance of viral genomes carrying mutations of the Q148R/H/K or of the Y143R/C pathways, which express higher levels of resistance. Even if some natural integrase polymorphisms can be part of this evolution process, these polymorphisms do not affect HIV susceptibility in the absence of primary mutations. Therefore, all HIV-1 subtypes and groups, together with HIV-2, are naturally susceptible to raltegravir. Finally, because interaction of integrase strand transfer inhibitors with the HIV integrase active site is comparable from one compound to another, raltegravir-resistant viruses express significant cross resistance to most other compounds of this new class of antiretroviral drugs.

  4. HIV resistance to raltegravir

    Directory of Open Access Journals (Sweden)

    Clavel François

    2009-11-01

    Full Text Available Abstract Similar to all antiretroviral drugs, failure of raltegravirbased treatment regimens to fully supress HIV replication almost invariably results in emergence of HIV resistance to this new drug. HIV resistance to raltegravir is the consequence of mutations located close to the integrase active site, which can be divided into three main evolutionary pathways: the N155H, the Q148R/H/K and the Y143R/C pathways. Each of these primary mutations can be accompanied by a variety of secondary mutations that both increase resistance and compensate for the variable loss of viral replicative capacity that is often associated with primary resistance mutations. One unique property of HIV resistance to raltegravir is that each of these different resistance pathways are mutually exclusive and appear to evolve separately on distinct viral genomes. Resistance is frequently initiated by viruses carrying mutations of the N155H pathway, followed by emergence and further dominance of viral genomes carrying mutations of the Q148R/H/K or of the Y143R/C pathways, which express higher levels of resistance. Even if some natural integrase polymorphisms can be part of this evolution process, these polymorphisms do not affect HIV susceptibility in the absence of primary mutations. Therefore, all HIV-1 subtypes and groups, together with HIV-2, are naturally susceptible to raltegravir. Finally, because interaction of integrase strand transfer inhibitors with the HIV integrase active site is comparable from one compound to another, raltegravir-resistant viruses express significant cross resistance to most other compounds of this new class of antiretroviral drugs.

  5. Behavior therapy and callous-unemotional traits: effects of a pilot study examining modified behavioral contingencies on child behavior.

    Science.gov (United States)

    Miller, Natalie V; Haas, Sarah M; Waschbusch, Daniel A; Willoughby, Michael T; Helseth, Sarah A; Crum, Kathleen I; Coles, Erika K; Pelham, William E

    2014-09-01

    The conduct problems of children with callous-unemotional (CU) traits (i.e., lack of empathy, lack of guilt/lack of caring behaviors) are particularly resistant to current behavioral interventions, and it is possible that differential sensitivities to punishment and reward may underlie this resistance. Children with conduct problems and CU (CPCU) are less responsive to behavioral punishment techniques (e.g., time-out), whereas reward techniques (e.g., earning points for prizes or activities) are effective for reducing conduct problems. This study examined the efficacy of modified behavioral interventions, which de-emphasized punishment (Condition B) and emphasized reward techniques (Condition C), compared with a standard behavioral intervention (Condition A). Interventions were delivered through a summer treatment program over 7 weeks with an A-B-A-C-A-BC-A design to a group of 11 children (7-11 years; 91% male). All children were diagnosed with either oppositional defiant disorder or conduct disorder, in addition to attention-deficit hyperactivity disorder. Results revealed the best treatment response occurred during the low-punishment condition, with rates of negative behavior (e.g., aggression, teasing, stealing) increasing over the 7 weeks. However, there was substantial individual variability in treatment response, and several children demonstrated improvement during the modified intervention conditions. Future research is necessary to disentangle treatment effects from order effects, and implications of group treatment of CPCU children (i.e., deviancy training) are discussed.

  6. Epidemiology of nosocomial bacteria resistant to antimicrobials

    Directory of Open Access Journals (Sweden)

    Cristina E. Cabrera

    2011-03-01

    Full Text Available Nosocomial infections are a major challenge for public health because of the high rates of morbidity and mortality generated. It was considered that the excessive or inappropriate use of antibiotics triggers the emergence of resistant strains. Among the clinically important bacteria that most commonly cause nososcomial infections, Gram positive multiresistant pathogens stand out such as methicillin-resistant Staphylococcus aureus (MRSA and vancomycin-resistant Enterococcus spp (VRE, and the Gram negative strains of Klebsiella pneumoniae, Escherichia coli, Pseudomonas spp. and Acinetobacter baumannii producing expanded spectrum b-lactamases (ESbL. This review describes the behavior of the main bacterial pathogens resistant to antibiotics that cause infections in Europe, United States, and Latin America, emphasizing studies of molecular epidemiology on a global scale, including the major epidemiological studies in Colombia. The genetic structure of S. aureus and Enterococcus spp strains shows a clonal characteristic favored by the predominance of a small number of clones with the capacity to spread globally, due probably to cross-infection. However, the introduction of MRSA strains from the community encourages genetic diversity, tending to establish a genetic polyclonal endemic structure in places like the United States. In Gram negative bacteria, the high genetic diversity among isolates, mainly in Latin American countries, indicates that the polyclonal spread is influenced by horizontal transfer of plasmids, by excessive exposure to antibiotics, and prolonged hospital stays. In Colombia, there is information on nosocomial resistant pathogens, but molecular epidemiological information is still scarce.

  7. Epidemiology of nosocomial bacteria resistant to antimicrobials

    Directory of Open Access Journals (Sweden)

    Cristina E Cabrera

    2011-04-01

    Full Text Available Nosocomial infections are a major challenge for public health because of the high rates of morbidity and mortality generated. It was considered that the excessive or inappropriate use of antibiotics triggers the emergence of resistant strains. Among the clinically important bacteria that most commonly cause nososcomial infections, Gram positive multiresistant pathogens stand out such as methicillin-resistant Staphylococcus aureus (MRSA and vancomycin-resistant Enterococcus spp (VRE, and the Gram negative strains of Klebsiella pneumoniae, Escherichia coli, Pseudomonas spp. and Acinetobacter baumannii producing expanded spectrum b-lactamases (ESbL. This review describes the behavior of the main bacterial pathogens resistant to antibiotics that cause infections in Europe, United States, and Latin America, emphasizing studies of molecular epidemiology on a global scale, including the major epidemiological studies in Colombia. The genetic structure of S. aureus and Enterococcus spp strains shows a clonal characteristic favored by the predominance of a small number of clones with the capacity to spread globally, due probably to cross-infection. However, the introduction of MRSA strains from the community encourages genetic diversity, tending to establish a genetic polyclonal endemic structure in places like the United States. In Gram negative bacteria, the high genetic diversity among isolates, mainly in Latin American countries, indicates that the polyclonal spread is influenced by horizontal transfer of plasmids, by excessive exposure to antibiotics, and prolonged hospital stays. In Colombia, there is information on nosocomial resistant pathogens, but molecular epidemiological information is still scarce.

  8. Resistance switching memory in perovskite oxides

    Energy Technology Data Exchange (ETDEWEB)

    Yan, Z.B., E-mail: zbyan@nju.edu.cn; Liu, J.-M., E-mail: liujm@nju.edu.cn

    2015-07-15

    The resistance switching behavior has recently attracted great attentions for its application as resistive random access memories (RRAMs) due to a variety of advantages such as simple structure, high-density, high-speed and low-power. As a leading storage media, the transition metal perovskite oxide owns the strong correlation of electrons and the stable crystal structure, which brings out multifunctionality such as ferroelectric, multiferroic, superconductor, and colossal magnetoresistance/electroresistance effect, etc. The existence of rich electronic phases, metal–insulator transition and the nonstoichiometric oxygen in perovskite oxide provides good platforms to insight into the resistive switching mechanisms. In this review, we first introduce the general characteristics of the resistance switching effects, the operation methods and the storage media. Then, the experimental evidences of conductive filaments, the transport and switching mechanisms, and the memory performances and enhancing methods of perovskite oxide based filamentary RRAM cells have been summarized and discussed. Subsequently, the switching mechanisms and the performances of the uniform RRAM cells associating with the carrier trapping/detrapping and the ferroelectric polarization switching have been discussed. Finally, the advices and outlook for further investigating the resistance switching and enhancing the memory performances are given.

  9. Oxygen-induced bi-modal failure phenomenon in SiOx-based resistive switching memory

    Science.gov (United States)

    Chang, Yao-Feng; Ji, Li; Wu, Zhuo-Jie; Zhou, Fei; Wang, Yanzhen; Xue, Fei; Fowler, Burt; Yu, Edward T.; Ho, Paul S.; Lee, Jack C.

    2013-07-01

    The ambient gas effect in SiOx-based resistive switching memory has been studied. After the electroforming process, resistive switching behavior functions in vacuum as well as in nitrogen without dramatic degradation. However, introducing an oxygen-nitrogen ambient suppresses resistive switching behavior at pressures above 1 Torr. Resistive switching is fully reestablished in oxygen-exposed devices after a vacuum recovery step. The failure phenomena can be described by Monte Carlo simulation using bi-modal statistics to enable feature distribution modeling of failure modes. Design criteria and guidelines are identified for packaging of future oxygen-sensor and of nonvolatile memory applications.

  10. Behavioral evidence for local reduction of aphid-induced resistance

    NARCIS (Netherlands)

    Prado, E.; Tjallingii, W.F.

    2007-01-01

    Twenty-five aphids of three different species, Brevicoryne brassicae L, Myzus persicae Schulzer, and Rhopalosiphum padi L(Hemiptera: Aphididae) were each allowed to infest leaves of a young plant of their respective host plant species for 4 days, except that the oldest expanded leaf (the `systemic¿

  11. Tribological and corrosion behaviors of carburized AISI 4340 steel

    Science.gov (United States)

    Thong-on, Atcharawadi; Boonruang, Chatdanai

    2016-01-01

    AISI 4340 steel is widely used in automotive and aircraft industries as gear components. In such applications, surface hardening processes such as carburizing are required in order to improve the life time of the components. There are many studies showing the tribological behavior of the carburized steel, but the corrosion behavior has not yet been clarified. This paper reports on both tribological and corrosion behaviors of the carburized AISI 4340 steel. Factor associated with carburizing, such as the quantities of deposited carbon, dissolved carbon, and formed Cr23C6 and Fe3C, affect the tribological and corrosion behaviors of the steel by improving hardness, friction, lubrication, and wear resistance; but corrosion resistance is reduced. The dissolved carbon affects the formation of the oxide layer of the carburized steel, by obstructing the continuous oxide layer formation and by decreasing the chromium content of the steel, leading to the decrease in the corrosion resistance of the steel.

  12. A Note on Soil Structure Resistance of Natural Marine Deposits

    Institute of Scientific and Technical Information of China (English)

    洪振舜; 刘松玉; 刘志方

    2004-01-01

    It has been well documented that natural normally-consolidated marine soils are generally subjected to the effects of soil structure. The interpretation of the resistance of soil structure is an important issue in the theory study and engineering practice of ocean engineering and geotechnical engineering. It is traditionally considered that the resistance of soil structure gradually disappears with increasing stress level when the applied stress is beyond the consolidation yield stress.In this study, however, it is found that this traditional interpretation of the resistance of soil structure can not explain the strength behavior of natural marine deposits with a normally-consolidated stress history. A new interpretation of the resistance of soil structure is proposed based on the strength behavior. In the preyield state, the undrained strength of natural marine deposits is composed of two components: one developed by the applied stress and the other developed by the resistance of soil structure. When the applied stress is beyond the consolidation yield stress, the strength behavior is independent of the resistance of soil structure.

  13. Method of stimulus combination impacts resistance to extinction.

    Science.gov (United States)

    Podlesnik, Christopher A; Bai, John Y H

    2015-07-01

    Reinforcing an alternative response in the presence of the stimuli governing a target response increases resistance to extinction of target responding, relative to training target responding on its own. Conversely, training alternative and target responses in the presence of different stimuli and combining those stimuli only decreases resistance to extinction of target responding, relative to target responding on its own. The present study assessed how different methods of combining discriminative stimuli influence resistance to extinction of responding in pigeons. As in previous studies, combining stimuli across different keys only decreased resistance to extinction of target responding relative to target responding on its own. In comparison, combining stimuli on the same key initially increased resistance to extinction of target responding, but repeated tests resulted in similar levels of responding as target responding with stimuli combined on separate keys. Moreover, greater overall reinforcement rates produced greater resistance to extinction with both methods of combining stimuli, consistent with behavioral momentum theory. These findings reveal several behavioral processes influence the outcome of combining stimuli--including perceptual processes, discriminative control by contingencies, response competition, and behavioral momentum.

  14. Linezolid Resistance in Staphylococci

    Directory of Open Access Journals (Sweden)

    Stefania Stefani

    2010-06-01

    Full Text Available Linezolid, the first oxazolidinone to be used clinically, is effective in the treatment of infections caused by various Gram-positive pathogens, including multidrug resistant enterococci and methicillin-resistant Staphylococus aureus. It has been used successfully for the treatment of patients with endocarditis and bacteraemia, osteomyelitis, joint infections and tuberculosis and it is often used for treatment of complicated infections when other therapies have failed. Linezolid resistance in Gram-positive cocci has been encountered clinically as well as in vitro, but it is still a rare phenomenon. The resistance to this antibiotic has been, until now, entirely associated with distinct nucleotide substitutions in domain V of the 23S rRNA genes. The number of mutated rRNA genes depends on the dose and duration of linezolid exposure and has been shown to influence the level of linezolid resistance. Mutations in associated ribosomal proteins also affect linezolid activity. A new phenicol and clindamycin resistance phenotype has recently been found to be caused by an RNA methyltransferase designated Cfr. This gene confers resistance to lincosamides, oxazolidinones, streptogramin A, phenicols and pleuromutilins, decrease the susceptibility of S. aureus to tylosin, to josamycin and spiramycin and thus differs from erm rRNA methylase genes. Research into new oxazolidinones with improved characteristics is ongoing. Data reported in patent applications demonstrated that some oxazolidinone derivatives, also with improved characteristics with respect to linezolid, are presently under study: at least three of them are in an advanced phase of development.

  15. Genetics Home Reference: clopidogrel resistance

    Science.gov (United States)

    ... Me Understand Genetics Home Health Conditions clopidogrel resistance clopidogrel resistance Enable Javascript to view the expand/collapse boxes. Download PDF Open All Close All Description Clopidogrel resistance is a condition in which the drug ...

  16. From Behaviorism to Selectionism.

    Science.gov (United States)

    Vargas, Ernest A.

    1993-01-01

    Discusses behaviorism and the gradual shift to a theory of selectionism. Highlights include the development of behaviorism as a part of psychology, including Skinner's theories; varieties of behaviorism, including behavioral analysis; behaviorology in other disciplinary settings; effects of contingencies upon behavior; and the prospects for…

  17. Resistance to Powdery Mildews

    DEFF Research Database (Denmark)

    Siwoszek, Agnieszka Izabela

    how the basic resistance components contribute to resistance against powdery mildews. Furthermore, I propose an alternative strategy of achieving resistance to barley powdery mildew by application of peptide aptamers. Peptide aptamers are small proteins selected to specifically target conserved Yx......C motif of barley powdery mildew effectors. I present a proof-of-concept study in Arabidopsis, where overexpression of peptide aptamers significantly reduced the susceptibility to barley powdery mildew. Moreover, I set the discovery in a bigger context by summarizing genetic engineering technologies...

  18. Multidrug-resistant tuberculosis

    Directory of Open Access Journals (Sweden)

    McNerney Ruth

    2008-01-01

    Full Text Available Abstract Background With almost 9 million new cases each year, tuberculosis remains one of the most feared diseases on the planet. Led by the STOP-TB Partnership and WHO, recent efforts to combat the disease have made considerable progress in a number of countries. However, the emergence of mutated strains of Mycobacterium tuberculosis that are resistant to the major anti-tuberculosis drugs poses a deadly threat to control efforts. Multidrug-resistant tuberculosis (MDR-TB has been reported in all regions of the world. More recently, extensively drug resistant-tuberculosis (XDR-TB that is also resistant to second line drugs has emerged in a number of countries. To ensure that adequate resources are allocated to prevent the emergence and spread of drug resistance it is important to understand the scale of the problem. In this article we propose that current methods of describing the epidemiology of drug resistant tuberculosis are not adequate for this purpose and argue for the inclusion of population based statistics in global surveillance data. Discussion Whereas the prevalence of tuberculosis is presented as the proportion of individuals within a defined population having disease, the prevalence of drug resistant tuberculosis is usually presented as the proportion of tuberculosis cases exhibiting resistance to anti-tuberculosis drugs. Global surveillance activities have identified countries in Eastern Europe, the former Soviet Union and regions of China as having a high proportion of MDR-TB cases and international commentary has focused primarily on the urgent need to improve control in these settings. Other regions, such as sub-Saharan Africa have been observed as having a low proportion of drug resistant cases. However, if one considers the incidence of new tuberculosis cases with drug resistant disease in terms of the population then countries of sub-Saharan Africa have amongst the highest rates of transmitted MDR-TB in the world. We propose

  19. Resistive random access memory utilizing ferritin protein with Pt nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Uenuma, Mutsunori; Kawano, Kentaro; Zheng Bin; Okamoto, Naofumi; Horita, Masahiro; Yoshii, Shigeo; Yamashita, Ichiro; Uraoka, Yukiharu, E-mail: uenuma@ms.naist.jp [Nara Institute of Science and Technology, 8916-5, Takayama, Ikoma, Nara 630-0192 (Japan)

    2011-05-27

    This study reports controlled single conductive paths found in resistive random access memory (ReRAM) formed by embedding Pt nanoparticles (Pt NPs) in NiO film. Homogeneous Pt NPs produced and placed by ferritin protein produce electric field convergence which leads to controlled conductive path formation. The ReRAM with Pt NPs shows stable switching behavior. A Pt NP density decrease results in an increase of OFF state resistance and decrease of forming voltage, whereas ON resistance was independent of the Pt NP density, which indicates that a single metal NP in a memory cell will achieve low power and stable operation.

  20. Colossal resistance switching in Pt/BiFeO{sub 3}/Nb:SrTiO{sub 3} memristor

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Shuxiang; Ren, Lizhu; Yu, Fengmei; Yang, Kungan; Yang, Mei; Wang, Yunjia; Meng, Meng; Zhou, Wenqi; Li, Shuwei [Sun Yat-Sen University, State Key Laboratory of Optoelectronic Materials and Technologies, School of Physics and Engineering, Guangzhou (China)

    2014-09-15

    We report reversible resistance switching behaviors in Pt/BiFeO{sub 3}/Nb:SrTiO{sub 3} memristor. The resistance of the junctions can be tuned up to about five orders of magnitude by applying voltage pulses at room temperature, which exhibits excellent retention and anti-fatigue characteristics. The high performances are promising for employing ferroelectric junctions in nonvolatile memory and logic devices. The nonvolatile resistance switching behaviors could be attributed to the formation and annihilation of trap centers in the BFO films, resulting in Poole-Frenkel emission for low resistance state and the thermionic emission for high resistance state, respectively. (orig.)

  1. Hydraulic resistance of biofilms

    KAUST Repository

    Dreszer, C.

    2013-02-01

    Biofilms may interfere with membrane performance in at least three ways: (i) increase of the transmembrane pressure drop, (ii) increase of feed channel (feed-concentrate) pressure drop, and (iii) increase of transmembrane passage. Given the relevance of biofouling, it is surprising how few data exist about the hydraulic resistance of biofilms that may affect the transmembrane pressure drop and membrane passage. In this study, biofilms were generated in a lab scale cross flow microfiltration system at two fluxes (20 and 100Lm-2h-1) and constant cross flow (0.1ms-1). As a nutrient source, acetate was added (1.0mgL-1 acetate C) besides a control without nutrient supply. A microfiltration (MF) membrane was chosen because the MF membrane resistance is very low compared to the expected biofilm resistance and, thus, biofilm resistance can be determined accurately. Transmembrane pressure drop was monitored. As biofilm parameters, thickness, total cell number, TOC, and extracellular polymeric substances (EPS) were determined, it was demonstrated that no internal membrane fouling occurred and that the fouling layer actually consisted of a grown biofilm and was not a filter cake of accumulated bacterial cells. At 20Lm-2h-1 flux with a nutrient dosage of 1mgL-1 acetate C, the resistance after 4 days reached a value of 6×1012m-1. At 100Lm-2h-1 flux under the same conditions, the resistance was 5×1013m-1. No correlation of biofilm resistance to biofilm thickness was found; Biofilms with similar thickness could have different resistance depending on the applied flux. The cell number in biofilms was between 4×107 and 5×108 cellscm-2. At this number, bacterial cells make up less than a half percent of the overall biofilm volume and therefore did not hamper the water flow through the biofilm significantly. A flux of 100Lm-2h-1 with nutrient supply caused higher cell numbers, more biomass, and higher biofilm resistance than a flux of 20Lm-2h-1. However, the biofilm thickness

  2. Resistance Fluctuations in GaAs Nanowire Grids

    Directory of Open Access Journals (Sweden)

    Ivan Marasović

    2014-01-01

    Full Text Available We present a numerical study on resistance fluctuations in a series of nanowire-based grids. Each grid is made of GaAs nanowires arranged in parallel with metallic contacts crossing all nanowires perpendicularly. Electrical properties of GaAs nanowires known from previous experimental research are used as input parameters in the simulation procedure. Due to the nonhomogeneous doping, the resistivity changes along nanowire. Allowing two possible nanowire orientations (“upwards” or “downwards”, the resulting grid is partially disordered in vertical direction which causes resistance fluctuations. The system is modeled using a two-dimensional random resistor network. Transfer-matrix computation algorithm is used to calculate the total network resistance. It is found that probability density function (PDF of resistance fluctuations for a series of nanowire grids changes from Gaussian behavior towards the Bramwell-Holdsworth-Pinton distribution when both nanowire orientations are equally represented in the grid.

  3. Polystyrene negative resist for high-resolution electron beam lithography

    Directory of Open Access Journals (Sweden)

    Ma Siqi

    2011-01-01

    Full Text Available Abstract We studied the exposure behavior of low molecular weight polystyrene as a negative tone electron beam lithography (EBL resist, with the goal of finding the ultimate achievable resolution. It demonstrated fairly well-defined patterning of a 20-nm period line array and a 15-nm period dot array, which are the densest patterns ever achieved using organic EBL resists. Such dense patterns can be achieved both at 20 and 5 keV beam energies using different developers. In addition to its ultra-high resolution capability, polystyrene is a simple and low-cost resist with easy process control and practically unlimited shelf life. It is also considerably more resistant to dry etching than PMMA. With a low sensitivity, it would find applications where negative resist is desired and throughput is not a major concern.

  4. Multidrug resistance associated proteins in multidrug resistance

    Institute of Scientific and Technical Information of China (English)

    Kamlesh Sodani; Atish Patel; Rishil J. Kathawala; Zhe-Sheng Chen

    2012-01-01

    Multidrug resistance proteins (MRPs) are members of the C family of a group of proteins named ATP-binding cassette (ABC) transporters.These ABC transporters together form the largest branch of proteins within the human body.The MRP family comprises of 13 members,of which MRP1 to MRP9 are the major transporters indicated to cause multidrug resistance in tumor cells by extruding anticancer drugs out of the cell.They are mainly lipophilic anionic transporters and are reported to transport free or conjugates of glutathione (GSH),glucuronate,or sulphate.In addition,MRP1 to MRP3 can transport neutral organic drugs in free form in the presence of free GSH.Collectively,MRPs can transport drugs that differ structurally and mechanistically,including natural anticancer drugs,nucleoside analogs,antimetabolites,and tyrosine kinase inhibitors.Many of these MRPs transport physiologically important anions such as leukotriene C4,bilirubin glucuronide,and cyclic nucleotides.This review focuses mainly on the physiological functions,cellular resistance characteristics,and probable in vivo role of MRP1 to MRP9.

  5. Mechanisms of drug resistance: daptomycin resistance.

    Science.gov (United States)

    Tran, Truc T; Munita, Jose M; Arias, Cesar A

    2015-09-01

    Daptomycin (DAP) is a cyclic lipopeptide with in vitro activity against a variety of Gram-positive pathogens, including multidrug-resistant organisms. Since its introduction into clinical practice in 2003, DAP has become an important key frontline antibiotic for severe or deep-seated infections caused by Gram-positive organisms. Unfortunately, DAP resistance (DAP-R) has been extensively documented in clinically important organisms such as Staphylococcus aureus, Enterococcus spp., and Streptococcus spp. Studies on the mechanisms of DAP-R in Bacillus subtilis and other Gram-positive bacteria indicate that the genetic pathways of DAP-R are diverse and complex. However, a common phenomenon emerging from these mechanistic studies is that DAP-R is associated with important adaptive changes in cell wall and cell membrane homeostasis with critical changes in cell physiology. Findings related to these adaptive changes have provided novel insights into the genetics and molecular mechanisms of bacterial cell envelope stress response and the manner in which Gram-positive bacteria cope with the antimicrobial peptide attack and protect vital structures of the cell envelope, such as the cell membrane. In this review, we will examine the most recent findings related to the molecular mechanisms of resistance to DAP in relevant Gram-positive pathogens and discuss the clinical implications for therapy against these important bacteria.

  6. Positive Behavior Support and Applied Behavior Analysis

    Science.gov (United States)

    Johnston, J. M.; Foxx, R. M.; Jacobson, J. W.; Green, G.; Mulick, J. A.

    2006-01-01

    This article reviews the origins and characteristics of the positive behavior support (PBS) movement and examines those features in the context of the field of applied behavior analysis (ABA). We raise a number of concerns about PBS as an approach to delivery of behavioral services and its impact on how ABA is viewed by those in human services. We…

  7. Antibiotic / Antimicrobial Resistance Glossary

    Science.gov (United States)

    ... Submit Search The CDC Get Smart: Know When Antibiotics Work Note: Javascript is disabled or is not ... What Everyone Should Know What You Can Do Antibiotic Resistance Q&As Fast Facts Antibiotics Quiz Glossary ...

  8. Tetracycline Antibiotics and Resistance.

    Science.gov (United States)

    Grossman, Trudy H

    2016-04-01

    Tetracyclines possess many properties considered ideal for antibiotic drugs, including activity against Gram-positive and -negative pathogens, proven clinical safety, acceptable tolerability, and the availability of intravenous (IV) and oral formulations for most members of the class. As with all antibiotic classes, the antimicrobial activities of tetracyclines are subject to both class-specific and intrinsic antibiotic-resistance mechanisms. Since the discovery of the first tetracyclines more than 60 years ago, ongoing optimization of the core scaffold has produced tetracyclines in clinical use and development that are capable of thwarting many of these resistance mechanisms. New chemistry approaches have enabled the creation of synthetic derivatives with improved in vitro potency and in vivo efficacy, ensuring that the full potential of the class can be explored for use against current and emerging multidrug-resistant (MDR) pathogens, including carbapenem-resistant Enterobacteriaceae, MDR Acinetobacter species, and Pseudomonas aeruginosa.

  9. Glucocorticoid feedback resistance.

    Science.gov (United States)

    De Kloet, E R; Vreugdenhil, E; Oitzl, M S; Joëls, M

    1997-01-01

    Glucocorticoid feedback resistance can be inherited or locally acquired. The implications of these two forms of resistance for disease are strikingly different. The inherited form is characterized by enhanced adrenocortical function and hypercorticism to compensate for a generalized deficit in the glucocorticoid receptor gene, but these individuals lack symptoms of Cushing's syndrome. By contrast, resistance acquired at the level of the hypothalamic corticotropin-releasing hormone (CRH) neurons is linked to hypercorticism, which is not compensatory but overexposes the rest of the body and the brain to glucocorticoids. This cell-specific glucocorticoid resistance can be acquired by genetically predisposed individuals failing to cope with (early) life events and causes enhanced vulnerability to disease-specific actions of glucocorticoids. (c) 1997, Elsevier Science Inc. (Trends Endocrinol Metab 1997; 8:26-33).

  10. Steroid resistant asthma.

    Science.gov (United States)

    Luhadia, S K

    2014-03-01

    Inspite of very safe and effective treatment, Bronchial asthmatics do not respond well in 5-10% of cases which are labelled as Refractory Asthma. Besides compliance, presence of psychogenic and trigger factors and comorbid illness, steroid insensitiveness or resistance may play a significant role in the poorly controlled/responding asthmatics. Type I Steroid resistance is due to lack of binding affinity of steroids to glucocorticoid receptors and may respond to higher doses of steroids while type II steroid resistance is because of reduced number of cells with glucocorticoid receptors, which is very rare and do not respond to even higher doses of systemic steroids and these cases require alternative/novel therapies. Future treatment of steroid resistant and severe refractory asthma is likely to be targeted towards cytokines and Bronchial Thermoplasty.

  11. Antibiotics and Resistance: Glossary

    Science.gov (United States)

    ... chromosomes and plasmids. Transposons often carry genes specifying antimicrobial resistance. Virus An extremely small infective agent, visible only with an electron microscope. Viruses can cause disease in humans, animals and plants. Viruses consist of a protein coat ...

  12. Animation of Antimicrobial Resistance

    Medline Plus

    Full Text Available ... Animal & Veterinary Cosmetics Tobacco Products Animal & ... antimicrobial resistance both emerges and proliferates among bacteria. Over time, the use of antimicrobial drugs will result in the development ...

  13. Development and characterization of advanced electron beam resists

    Science.gov (United States)

    Agrawal, Ankur

    Over the past twenty years, the amount of research and development work for electron beam resists has seriously lagged that performed for optical resists. This has been due mainly to the relatively low volume use of electron beam lithography for production purposes. However, as electron beam lithography is now becoming the primary solution for achieving future critical dimension requirements in mask making and appears to be a promising NGL technology, interest in electron beam resist development has increased in recent years. The primary issue in electron beam resist design centers around finding a single resist system that combines the required sensitivity and etch resistance that is needed to enable high volume production. In this work, the primary goal was to explore the development of a novel two-component non-chemically amplified electron beam resist material for high keV (>10 keV) patterning for mask-making with: (1) high contrast, (2) high sensitivity, (3) high resolution, and, (4) high etch resistance. Poly (2-methyl-1-pentene co 2-ethoxyethyl-methallyl ether sulfone) was used as a polymeric e-beam sensitive material conjunction with a series of commercial novolac resins to formulate electron beam resists. These two-component resists have been termed sulfone-novolac system (SNS) resists. The approach used in this project is to develop a suite of experimental tools and simulation models that can be used to aid in the rational design, formulation, and characterization of new electron beam resists. The main tasks that have been addressed are: (1) development of the electron beam resist characterization tool set, (2) understanding the fundamental material behavior of a non-chemically amplified polysulfone-novolac (SNS) e-beam resist for next generation mask making, (3) lithographic process development and optimization for the SNS resists, (4) evaluation of the lithographic performance of the SNS resists using the optimized processing conditions, and (5) develop

  14. Corrosion behavior of duplex coatings

    Directory of Open Access Journals (Sweden)

    K. Raghu Ram Mohan Reddy

    2016-07-01

    Full Text Available The titanium alloys are used in defense, aerospace, automobile, chemical plants and biomedical applications due to their very high strength and lightweight properties. However, corrosion is a life-limiting factor when Ti alloys are exposed to different chemical environments at high temperatures. In the present paper, duplex NiCrAlY/WC–Co coating is coated onto Ti6Al4V substrate to investigate the corrosion behavior of both coated samples and the substrate. The duplex coating was performed with NiCrAlY as the intermediate coat of 200 μm thickness deposited by HVOF process and WC–Co ceramic top coat with varying thicknesses of 250 μm, 350 μm and 450 μm deposited by DS process. Potentiodynamic polarization tests were employed to investigate the corrosion performance of duplex coated samples and substrate in Ringer’s solution at 37 °C and pH value was set to 5.7. Finally the results reveal that 350 μm thick coated samples showed highest corrosion resistance compared to 250 μm thick samples as well as bare substrate. However, the 450 μm thick coated sample showed poor corrosion resistance compared to the substrate. The scale formed on the samples upon corrosion was characterized by using SEM analysis to understand the degree of corrosion behavior.

  15. Rolling resistance of tires

    Energy Technology Data Exchange (ETDEWEB)

    Junio, M.; Roesgen, A.; Corvasce, F. [Goodyear Technical Center Luxembourg, Colmar-Berg (Luxembourg)

    1999-07-01

    After a review of the contribution of tire rolling resistance to fuel economy, the tire rolling resistance is defined and measurement methods discussed. The significant effects of the 'external' factors such as load, inflation, temperature, speed, etc. that are not controlled by the tire developers, are reviewed. Tire construction changes that reduce deformations and compound changes reducing hysteresis are discussed and information is provided on what has been achieved so far and what might be done in the future. (orig.)

  16. Stab resistant body armour

    OpenAIRE

    Horsfall, Ian

    2000-01-01

    There is now a widely accepted need for stab resistant body armour for the police in the UK. However, very little research has been done on knife resistant systems and the penetration mechanics of sharp projectiles are poorly understood. This thesis explores the general background to knife attack and defence with a particular emphasis on the penetration mechanics of edged weapons. The energy and velocity that can be achieved in stabbing actions has been determined for a numb...

  17. On the theory of behavioral mechanics.

    Science.gov (United States)

    Dzendolet, E

    1999-12-01

    The Theory of Behavioral Mechanics is the behavioral analogue of Newton's laws of motion, with the rate of responding in operant conditioning corresponding to physical velocity. In an earlier work, the basic relation between rate of responding and sessions under two FI schedules and over a range of commonly used session values had been shown to be a power function. Using that basic relation, functions for behavioral acceleration, mass, and momentum are derived here. Data from other laboratories also support the applicability of a power function to VI schedules. A particular numerical value is introduced here to be the standard reference value for the behavioral force under the VI-60-s schedule. This reference allows numerical values to be calculated for the behavioral mass and momentum of individual animals. A comparison of the numerical values of the momenta of two animals can be used to evaluate their relative resistances to change, e.g., to extinction, which is itself viewed as a continuously changing behavioral force being imposed on the animal. This overall numerical approach allows behavioral force-values to be assigned to various experimental conditions such as the evaluation of the behavioral force of a medication dosage.

  18. Repetitive maladaptive behavior: beyond repetition compulsion.

    Science.gov (United States)

    Bowins, Brad

    2010-09-01

    Maladaptive behavior that repeats, typically known as repetition compulsion, is one of the primary reasons that people seek psychotherapy. However, even with psychotherapeutic advances it continues to be extremely difficult to treat. Despite wishes and efforts to the contrary repetition compulsion does not actually achieve mastery, as evidenced by the problem rarely resolving without therapeutic intervention, and the difficulty involved in producing treatment gains. A new framework is proposed, whereby such behavior is divided into behavior of non-traumatic origin and traumatic origin with some overlap occurring. Repetitive maladaptive behavior of non-traumatic origin arises from an evolutionary-based process whereby patterns of behavior frequently displayed by caregivers and compatible with a child's temperament are acquired and repeated. It has a familiarity and ego-syntonic aspect that strongly motivates the person to retain the behavior. Repetitive maladaptive behavior of traumatic origin is characterized by defensive dissociation of the cognitive and emotional components of trauma, making it very difficult for the person to integrate the experience. The strong resistance of repetitive maladaptive behavior to change is based on the influence of both types on personality, and also factors specific to each. Psychotherapy, although very challenging at the best of times, can achieve the mastery wished and strived for, with the aid of several suggestions provided.

  19. Resistive switching in Pt/TiO{sub 2}/Pt

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Doo Seok

    2008-08-15

    Recently, the resistive switching behavior in TiO{sub 2} has drawn attention due to its application to resistive random access memory (RRAM) devices. TiO{sub 2} shows characteristic non-volatile resistive switching behavior, i.e. reversible switching between a high resistance state (HRS) and a low resistance state (LRS). Both unipolar resistive switching (URS) and bipolar resistive switching (BRS) are found to be observed in TiO{sub 2} depending on the compliance current for the electroforming. In this thesis the characteristic current-voltage (I-V) hysteresis in three different states of TiO{sub 2}, pristine, URS-activated, and BRS-activated states, was investigated and understood in terms of the migration of oxygen vacancies in TiO{sub 2}. The I-V hysteresis of pristine TiO{sub 2} was found to show volatile behavior. That is, the temporary variation of the resistance took place depending on the applied voltage. However, the I-V hysteresis of URS- and BRS-activated states showed non-volatile resistive switching behavior. Some evidences proving the evolution of oxygen gas during electroforming were obtained from time-of-flight secondary ion mass spectroscopy analysis and the variation of the morphology of switching cells induced by the electroforming. On the assumption that a large number of oxygen vacancies are introduced by the electroforming process, the I-V behavior in electroformed switching cells was simulated with varying the distribution of oxygen vacancies in electroformed TiO{sub x} (x behavior including the

  20. Behavior modification with culturally deprived school children: two case studies.

    Science.gov (United States)

    Wasik, B H; Senn, K; Welch, R H; Cooper, B R

    1969-01-01

    Techniques of behavior modification were employed with two second-grade Negro girls in a demonstration school for culturally deprived children to increase the girls' appropriate classroom behaviors. A classification system that provided for continuous categorization of behavior was used to code the children's behavior in two classroom situations. Data were also taken on the type, duration, and frequency of the teachers' verbal interactions. The study included four conditions: Baseline, Modification I, Postmodification, and Modification II. The treatment variable was positive social reinforcement-attention and approval contingent upon desirable classroom behaviors-which was presented, withheld, or withdrawn (timeout from social reinforcement). Withholding of social reinforcement was contingent upon inappropriate attention-getting behaviors. Timeout from social reinforcement was contingent upon behaviors classified as aggressive and resistive. After 25 days of Modification I, desirable behavior increased markedly for each girl. The teachers were then asked to return to their Baseline level of performance. The resultant behaviors demonstrated that for one girl, behavior was still primarily under the control of the treatment contingencies. For the second child, many desirable behaviors that had increased in frequency during Modification I remained high, but inappropriate behaviors increased. When treatment was reinstated, the amount of time spent in desirable behaviors increased and remained high for both girls. Three checks during the three months following data collection showed that these behaviors continued to remain high.

  1. Aqueous Corrosion Behavior of Iron aluminide Intermetallics

    Science.gov (United States)

    Sharma, Garima; Singh, P. R.; Sharma, R. K.; Gaonkar, K. B.; Ramanujan, R. V.

    2007-12-01

    Iron aluminide intermetallics based on DO3 ordered structure are being developed for use as structural materials and cladding material for conventional engineering alloys. Aqueous corrosion behavior of iron aluminides has been studied extensively by electrochemical techniques. Studies were carried out on pure Fe (99.9%), Fe-28Al (at.%), Fe-28Al-3Cr (at.%), and AISI SS 304 so as to compare and contrast their behavior in same experimental condition. Polarization behavior under different pH conditions was examined to evaluate their performance in acidic, basic, and neutral solutions. Pitting behavior was also studied in solution containing Cl-1 ions. The stability of the passive film formed was studied by current time transients and potential decay profiles. The presence of 3 at.% Cr in iron aluminides was found to improve the aqueous corrosion resistance and makes it comparable to AISI SS 304.

  2. The Psyche as Behavior

    Directory of Open Access Journals (Sweden)

    ARTURO CLAVIJO A.

    2013-12-01

    Full Text Available Behaviorism has argued that behavior is the Psyche and the subject matter of psychology. Although, some scientists had done empirical work with objective methods before 1913, the year in which John B. Watson published his manifesto, he was the first one to attempt a systematization of behavior as the Psyche, that is, as psychology’s subject matter. In this text, I outline Watson’s notion of behavior to compare it with two other forms of behaviorism: Skinner’s radical behaviorism and molar behaviorism. The purpose of the paper is to illustrate how the concept of behavior has been and is changing.

  3. Linezolid resistant Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Pavani Gandham

    2014-08-01

    Full Text Available Linezolid is the only antibiotic available as an oral formulation for resistant staphylococcal infections. It is effective in skin and soft tissue infections, nosocomial pneumonias including VAP, infective endocarditis and MRSA meningitis. It is also effective in the eradication of both nasal and throat colonization of MRSA. Its high bioavailability and post antibiotic effect, ease of switching to oral therapy during its use and the fact that it can be used in patients of all ages, also in patients with liver disease and poor kidney function and its increased effectiveness over glycopeptides makes this drug a precious drug in the treatment of resistant staphylococcal infections. Linezolid resistance in staphylococcus is defined as a linezolid MIC of and #8805;8 mg/L. Reported Linezolid resistance in India and elsewhere is 2-20%. There is clonal dissemination of Linezolid Resistant Staphylococcus aureus (LRSA within or across health care settings which demands continuous surveillance to determine the emergent risk of resistance strains and to establish guidelines for appropriate use. Clinical laboratories should confirm any LRSA preferably by a second method, prior to using linezolid for serious infections. Effective surveillance, more judicious use of this antibiotic, avoiding linezolid usage for empiric therapy in hospital acquired staphylococcus infections, optimization of the pharmacological parameters of the antibiotics in specific clinical situation, decreasing bacterial load by timely surgical debridement or drainage of collections, use of combination therapies would prevent the emergence of resistance to linezolid in staphylococcus aureus. [Int J Res Med Sci 2014; 2(4.000: 1253-1256

  4. Resistant starches and health.

    Science.gov (United States)

    Kendall, Cyril W C; Emam, Azadeh; Augustin, Livia S A; Jenkins, David J A

    2004-01-01

    It was initially hypothesized that resistant starches, i.e., starch that enters the colon, would have protective effects on chronic colonic diseases, including reduction of colon cancer risk and in the treatment of ulcerative colitis. Recent studies have confirmed the ability of resistant starch to increase fecal bulk, increase the molar ratio of butyrate in relation to other short-chain fatty acids, and dilute fecal bile acids. However the ability of resistant starch to reduce luminal concentrations of compounds that are damaging to the colonic mucosa, including fecal ammonia, phenols, and N-nitroso compounds, still requires clear demonstration. As such, the effectiveness of resistant starch in preventing or treating colonic diseases remains to be assessed. Nevertheless, there is a fraction of what has been termed resistant (RS1) starch, which enters the colon and acts as slowly digested or lente carbohydrate in the small intestine. Foods in this class are low glycemic index and have been shown to reduce the risk of chronic disease. They have been associated with systemic physiological effects such as reduced postprandial insulin levels and higher HDL cholesterol levels. Consumption of low glycemic index foods has been shown to be related to reductions in risk of coronary heart disease and Type 2 diabetes. Type 2 diabetes has in turn been related to a higher risk of colon cancer. If carbohydrates have a protective role in colon cancer prevention this may lie partly in the systemic effects of low glycemic index foods. The colonic advantages of different carbohydrates, varying in their glycemic index and resistant starch content, therefore, remain to be determined. However, as recent positive research findings continue to mount, there is reason for optimism over the possible health advantages of those resistant starches, which are slowly digested in the small intestine.

  5. Desiccation resistance in Arcobacter butzleri

    Directory of Open Access Journals (Sweden)

    Otth Laura

    2001-01-01

    Full Text Available The desiccation resistance of A. butzleri was studied. Two, 3 and 4 of the strains did not resist desiccation for more than 2, 12 and 36 h, respectively. Two strains resisted desiccation for > 48 h. A. butzleri seems to be more resistant to desiccation than the classical enteropathogenic Campylobacter species.

  6. MSMA resistance studies.

    Science.gov (United States)

    Camper, N D; Keese, R J; Coker, P S

    2004-05-01

    Monosodium methanearsonate (MSMA)-resistant and -susceptible common cocklebur (Xanthium strumarium L.) and cotton (Gossypium hirsutum L.) were treated with MSMA. Plant parameters analyzed were: glutathione synthetase activity, selected amino acid (arginine, glutamic acid, alanine, citrulline, glutamine, and glutathione) content and arsenic content (MSMA, total arsenic, and arsonate). No reduction of arsenic from the parent pentavalent form present in MSMA to the trivalent form was detected. Arginine, glutamic acid, and glutamine content increased in tissue three days after MSMA treatment. Glutathione content decreased during the first three days after treatment; however, five days after treatment the resistant biotype of cocklebur and cotton had elevated glutathione levels (8-20 times greater, respectively). Glutathione Synthetase activity was higher in cotton than in either of the cocklebur biotypes; MSMA did not affect its activity in cotton or either cocklebur biotype. Resistant biotypes have a slightly higher activity than the susceptible biotype. Tolerance of cotton to MSMA may be related to glutathione synthetase activity and possibly to the presence of phytochelatins. Also, increased glutathione levels in the resistant biotype may implicate phytochelatin involvement in the resistance mechanism.

  7. Spore Resistance Properties.

    Science.gov (United States)

    Setlow, Peter

    2014-10-01

    Spores of various Bacillus and Clostridium species are among the most resistant life forms known. Since the spores of some species are causative agents of much food spoilage, food poisoning, and human disease, and the spores of Bacillus anthracis are a major bioweapon, there is much interest in the mechanisms of spore resistance and how these spores can be killed. This article will discuss the factors involved in spore resistance to agents such as wet and dry heat, desiccation, UV and γ-radiation, enzymes that hydrolyze bacterial cell walls, and a variety of toxic chemicals, including genotoxic agents, oxidizing agents, aldehydes, acid, and alkali. These resistance factors include the outer layers of the spore, such as the thick proteinaceous coat that detoxifies reactive chemicals; the relatively impermeable inner spore membrane that restricts access of toxic chemicals to the spore core containing the spore's DNA and most enzymes; the low water content and high level of dipicolinic acid in the spore core that protect core macromolecules from the effects of heat and desiccation; the saturation of spore DNA with a novel group of proteins that protect the DNA against heat, genotoxic chemicals, and radiation; and the repair of radiation damage to DNA when spores germinate and return to life. Despite their extreme resistance, spores can be killed, including by damage to DNA, crucial spore proteins, the spore's inner membrane, and one or more components of the spore germination apparatus.

  8. Clopidogrel Resistance: Current Issues

    Directory of Open Access Journals (Sweden)

    NS Neki

    2016-05-01

    Full Text Available Antiplatelet agents are mainly used in the prevention and management of atherothrombotic complications. Dual antiplatelet therapy, combining aspirin and clopidogrel, is the standard care for patients having acute coronary syndromes or undergoing percutaneous coronary intervention according to the current ACC/AHA and ESC guidelines. But in spite of administration of dual antiplatelet therapy, some patients develop recurrent cardiovascular ischemic events especially stent thrombosis which is a serious clinical problem. Antiplatelet response to clopidogrel varies widely among patients based on ex vivo platelet function measurements. Clopidogrel is an effective inhibitor of platelet activation and aggregation due to its selective and irreversible blockade of the P2Y12 receptor. Patients who display little attenuation of platelet reactivity with clopidogrel therapy are labeled as low or nonresponders or clopidogrel resistant. The mechanism of clopidogrel resistance remains incompletely defined but there are certain clinical, cellular and genetic factors including polymorphisms responsible for therapeutic failure. Currently there is no standardized or widely accepted definition of clopidogrel resistance. The future may soon be realised in the routine measurement of platelet activity in the same way that blood pressure, cholesterol and blood sugar are followed to help guide the therapy, thus improving the care for millions of people. This review focuses on the methods used to identify patients with clopidogrel resistance, the underlying mechanisms, metabolism, clinical significance and current therapeutic strategies to overcome clopidogrel resistance. J Enam Med Col 2016; 6(1: 38-46

  9. Resistance and Its Consequences: The Street Culture of Punks.

    Science.gov (United States)

    Baron, Stephen W.

    1989-01-01

    Explores the street life of an adolescent subculture through field study of the Canadian West Coast punk rock subculture. Demonstrates through observation of the members, their behavior and attitudes, and the reactions of others to them, that their activities both represent, and are consequences of, resistance to the dominant order. (Author/JS)

  10. Listening to Rap: Cultures of Crime, Cultures of Resistance

    Science.gov (United States)

    Tanner, Julian; Asbridge, Mark; Wortley, Scot

    2009-01-01

    This research compares representations of rap music with the self-reported criminal behavior and resistant attitudes of the music's core audience. Our database is a large sample of Toronto high school students (n = 3,393) from which we identify a group of listeners, whose combination of musical likes and dislikes distinguish them as rap univores.…

  11. Stalking Antibiotic-Resistant Bacteria in Common Vegetables

    Science.gov (United States)

    Brock, David; Boeke, Caroline; Josowitz, Rebecca; Loya, Katherine

    2004-01-01

    The study developed a simple experimental protocol for studying antibiotic resistant bacteria that will allow students to determine the proportion of such bacteria found on common fruit and vegetable crops. This protocol can open up the world of environmental science and show how human behavior can dramatically alter ecosystems.

  12. Pharmacological Management of Treatment-Resistant Pediatric Depression

    Science.gov (United States)

    Kratochvil, Christopher J.; Wagner, Karen Dineen; Emslie, Graham; March, John

    2005-01-01

    A 13-year-old boy presents with treatment-resistant symptoms of major depression. This is his first episode of depression, initially treated with 200 mg sertraline for 12 weeks with no significant benefit. The severe depression has shown a partial response to weekly cognitive-behavioral therapy (CBT) and fluoxetine, which was titrated up to 60 mg…

  13. Resistance to Insecticides in Insects

    OpenAIRE

    2005-01-01

    In recent years, the frequent usage of insecticides in struggle aganist insects, has caused development of resistance to those chemicals in insects. The increase in dosage of insecticide used due to development of resistance in insects, causes important problems in terms of environment and human health. This study includes topics such as insecticides which are used frequently in insect struggle, insecticide resistant types, genetic changes posing resistance, enzymes of resistance and resistan...

  14. Biological improvement of radiation resistance

    Energy Technology Data Exchange (ETDEWEB)

    Chun, K. J.; Lee, Y. K.; Kim, J. S.; Kim, J. K.; Lee, S. J

    2000-08-01

    To investigate the mechanisms of gene action related to the radiation resistance in microorganisms could be essentially helpful for the development of radiation protectants and hormeric effects of low dose radiation. This book described isolation of radiation-resistant microorganisms, induction of radiation-resistant and functionally improved mutants by gamma-ray radiation, cloning and analysis of the radiation resistance related genes and analysis of the expressed proteins of the radiation resistant related genes.

  15. Contextual Influences on Resistance to Disruption in Children with Intellectual Disabilities

    Science.gov (United States)

    Lionello-DeNolf, Karen; Dube, William V.

    2011-01-01

    Training context can influence resistance to disruption under differing reinforcement schedules. With nonhumans, when relatively lean and rich reinforcement schedules are experienced in the context of a multiple schedule, greater resistance is found in the rich than the lean component, as described by behavioral momentum theory. By contrast, when…

  16. A MODEL OF PESTICIDE RESISTANCE AS A COMMON PROPERTY AND EXHAUSTIBLE RESOURCE

    OpenAIRE

    Secchi, Silvia; Bruce A. Babcock

    1999-01-01

    A dynamic farm production model analyzes the interaction between the externalities caused by pest mobility and the development of pesticide resistance, a nonrenewable resource, in the context of agricultural biotechnologies. The model measures the effect of farmers' myopic behavior and the impact of pest mobility on the path of resistance.

  17. Environmental Considerations in the Studies of Corrosion Resistant Alloys for High-Level Radioactive Waste Containment

    Energy Technology Data Exchange (ETDEWEB)

    Ilevbare, G O; Lian, T; Farmer, J C

    2001-11-26

    The corrosion resistance of Alloy 22 (UNS No.: N06022) was studied in simulated ground water of different pH values and ionic contents at various temperatures. Potentiodynamic polarization techniques were used to study the electrochemical behavior and measure the critical potentials in the various systems. Alloy 22 was found to be resistant to localized corrosion in the simulated ground waters tested.

  18. Pyrethroid resistance in mosquitoes

    Institute of Scientific and Technical Information of China (English)

    NANNAN LIU; QIANG XU; FANG ZHU; LEE ZHANG

    2006-01-01

    Repeated blood feedings throughout their life span have made mosquitoes ideal transmitters of a wide variety of disease agents. Vector control is a very important part of the current global strategy for the control of mosquito-associated diseases and insecticide application is the most important component in this effort. Pyrethroids, which account for 25% of the world insecticide market, are currently the most widely used insecticides for the indoor control of mosquitoes and are the only chemical recommended for the treatment of mosquito nets, the main tool for preventing malaria in Africa. However, mosquito-borne diseases are now resurgent, largely because of insecticide resistance that has developed in mosquito vectors and the anti-parasite drug resistance of parasites. This paper reviews our current knowledge of the molecular mechanisms governing metabolic detoxification and the development of target site insensitivity that leads to pyrethroid resistance in mosquitoes.

  19. Heat-resistant materials

    CERN Document Server

    1997-01-01

    This handbook covers the complete spectrum of technology dealing with heat-resistant materials, including high-temperature characteristics, effects of processing and microstructure on high-temperature properties, materials selection guidelines for industrial applications, and life-assessment methods. Also included is information on comparative properties that allows the ranking of alloy performance, effects of processing and microstructure on high-temperature properties, high-temperature oxidation and corrosion-resistant coatings for superalloys, and design guidelines for applications involving creep and/or oxidation. Contents: General introduction (high-temperature materials characteristics, and mechanical and corrosion properties, and industrial applications); Properties of Ferrous Heat-Resistant Alloys (carbon, alloy, and stainless steels; alloy cast irons; and high alloy cast steels); Properties of superalloys (metallurgy and processing, mechanical and corrosion properties, degradation, and protective coa...

  20. Mathematical principles of reinforcement and resistance to change.

    Science.gov (United States)

    Nevin, John A.

    2003-04-28

    Although Killeen's mathematical principles of reinforcement (MPR) apply to the asymptotic rate of a free operant after extended exposure to a single schedule of reinforcement, they can be extended to resistance to change in multiple schedules via alterations in the parameter representing the activating effects of reinforcers. MPR's predictions of resistance to change in relation to reinforcer rate on variable-interval (VI) schedules are empirically correct and agree with behavioral momentum theory (BMT). However, both MPR and BMT encounter problems in accounting for the effects of delayed reinforcement on resistance to change, relative to immediate reinforcement at the same rate. Further problems are raised by differences in resistance to change between variable-ratio (VR) and variable-interval performances maintained by the same reinforcer rate. With both delayed versus immediate reinforcement and variable-ratio versus variable-interval reinforcement, differential resistance to change is negatively correlated with the log ratios of baseline response rates when reinforcer rates are equated. Cases where resistance to change varies despite equated reinforcer rates, and the correlations among behavioral measures, provide challenges and opportunities for both MPR and BMT.

  1. Generalized effective medium resistivity model for low resistivity reservoir

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    With the advancement in oil exploration,producible oil and gas are being found in low resistivity reservoirs,which may otherwise be erroneously thought as water zones from their resistivity.However,the evaluation of low resistivity reservoirs remains difficult from log interpretation.Since low resistivity in hydrocarbon bearing sands can be caused by dispersed clay,laminated shale,conductive matrix grains,microscopic capillary pores and high saline water,a new resistivity model is required for more accurate hydrocarbon saturation prediction for low resistivity formations.Herein,a generalized effective medium resistivity model has been proposed for low resistivity reservoirs,based on experimental measurements on artificial low resistivity shaly sand samples,symmetrical anisotropic effective medium theory for resistivity interpretations,and geneses and conductance mechanisms of low resistivity reservoirs.By analyzing effects of some factors on the proposed model,we show theoretically the model can describe conductance mechanisms of low resistivity reservoirs with five geneses.Also,shale distribution largely affects water saturation predicted by the model.Resistivity index decreases as fraction and conductivity of laminated shale,or fraction of dispersed clay,or conductivity of rock matrix grains increases.Resistivity index decreases as matrix percolation exponent,or percolation rate of capillary bound water increases,and as percolation exponent of capillary bound water,or matrix percolation rate,or free water percolation rate decreases.Rock sample data from low resistivity reservoirs with different geneses and interpretation results for log data show that the proposed model can be applied in low resistivity reservoirs containing high salinity water,dispersed clay,microscopic capillary pores,laminated shale and conductive matrix grains,and thus is considered as a generalized resistivity model for low resistivity reservoir evaluation.

  2. Generalized effective medium resistivity model for low resistivity reservoir

    Institute of Scientific and Technical Information of China (English)

    SONG YanJie; TANG XiaoMin

    2008-01-01

    With the advancement in oil exploration, producible oil and gas are being found in low resistivity reservoirs, which may otherwise be erroneously thought as water zones from their resistivity. However,the evaluation of low resistivity reservoirs remains difficult from log interpretation. Since low resistivity in hydrocarbon bearing sands can be caused by dispersed clay, laminated shale, conductive matrix grains, microscopic capillary pores and high saline water, a new resistivity model is required for more accurate hydrocarbon saturation prediction for low resistivity formations. Herein, a generalized effective medium resistivity model has been proposed for low resistivity reservoirs, based on experimental measurements on artificial low resistivity shaly sand samples, symmetrical anisotropic effective medium theory for resistivity interpretations, and geneses and conductance mechanisms of low resistivity reservoirs. By analyzing effects of some factors on the proposed model, we show theoretically the model can describe conductance mechanisms of low resistivity reservoirs with five geneses. Also,shale distribution largely affects water saturation predicted by the model. Resistivity index decreases as fraction and conductivity of laminated shale, or fraction of dispersed clay, or conductivity of rock matrix grains increases. Resistivity index decreases as matrix percolation exponent, or percolation rate of capillary bound water increases, and as percolation exponent of capillary bound water, or matrix percolation rate, or free water percolation rate decreases. Rock sample data from low resistivity reservoirs with different geneses and interpretation results for log data show that the proposed model can be applied in low resistivity reservoirs containing high salinity water, dispersed clay, microscopic capillary pores, laminated shale and conductive matrix grains, and thus is considered as a generalized resistivity model for low resistivity reservoir evaluation.

  3. Kinetically Controlled Drug Resistance

    DEFF Research Database (Denmark)

    Sun, Xin E.; Hansen, Bjarne Gram; Hedstrom, Lizbeth

    2011-01-01

    The filamentous fungus Penicillium brevicompactum produces the immunosuppressive drug mycophenolic acid (MPA), which is a potent inhibitor of eukaryotic IMP dehydrogenases (IMPDHs). IMPDH catalyzes the conversion of IMP to XMP via a covalent enzyme intermediate, E-XMP*; MPA inhibits by trapping E...... of resistance is not apparent. Here, we show that, unlike MPA-sensitive IMPDHs, formation of E-XMP* is rate-limiting for both PbIMPDH-A and PbIMPDH-B. Therefore, MPA resistance derives from the failure to accumulate the drug-sensitive intermediate....

  4. Fire Resistant Panels for the Tunnel Linings

    Directory of Open Access Journals (Sweden)

    Gravit Marina

    2016-01-01

    Full Text Available Presents the results of studies of innovative materials in the field of experimental and theoretical research fire resistance fireproof panels Pyro-Safe Aestuver T. Owing to the assembly simplicity, materials cheapness, high ecological standard, recycling, reuse potential, are benefit. Research work is running to improve the knowledge about fireproof panels Pyro-Safe Aestuver T for tunnel lining, its basic performance, its long term behavior and in particular also its fire proof for example when used for the lining of road tunnels.

  5. Measurement of Dynamic Resistance in Resistance Spot Welding

    DEFF Research Database (Denmark)

    Wu, Pei; Zhang, Wenqi; Bay, Niels

    Through years, the dynamic resistance across the electrodes has been used for weld quality estimation and contact resistance measurement. However, the previous methods of determining the dynamic resistance were mostly based on measuring the voltage and current on the secondary side...... of the transformer in resistance welding machines, implying defects from induction noise and interference with the leads connected to the electrodes for measuring the voltage. In this study, the dynamic resistance is determined by measuring the voltage on the primary side and the current on the secondary side......, as another application, the proposed method is used to measure the faying surface contact resistance....

  6. Does Culture Affect how People Receive and Resist Persuasive Messages? Research Proposals about Resistance to Persuasion in Cultural Groups

    Directory of Open Access Journals (Sweden)

    Renata Kolodziej-Smith

    2013-10-01

    Full Text Available Abstract Even though persuasion has been a widely researched topic in consumer behavior, the great majority of these studies have involved American consumers and focused on persuasion itself, with very few addressing resistance to persuasive attempts. None has addressed resistance to persuasion in a cross-cultural context. We aim to contribute to closing this gap in the literature with this paper. Specifically, we aim to expand knowledge of the persuasive process by applying the cultural dimensions of self-construal and face negotiation theories to Gopinath and Nyer’s (2009 work conducted on American consumers about the effect of public commitment on resistance to persuasion. Our research focus is on why people from different ethnic/cultural backgrounds will receive or resist persuasive messages differently. We anchor this notion in face negotiation theory (Ting-Toomey, 2005. This perspective addresses different types of facework behaviors that people choose in a multicultural environment, thus shedding light on processes underlying persuasion and resistance to persuasion mechanisms as influenced by culture. Understanding the effects of cultural differences on a person’s reception of, or resistance to, counter-attitudinal persuasion should be valuable to managers who make decisions about cultural adaptations and target audience changes.

  7. Advances in pneumococcal antibiotic resistance.

    Science.gov (United States)

    Song, Jae-Hoon

    2013-10-01

    Antimicrobial resistance and serotypes in Streptococcus pneumoniae have been evolving with the widespread use of antibiotics and the introduction of pneumococcal conjugate vaccines (PCV). Particularly, among various types of antimicrobial resistance, macrolide resistance has most remarkably increased in many parts of the world, which has been reported to be >70% among clinical isolates from Asian countries. Penicillin resistance has dramatically decreased among nonmeningeal isolates due to the changes in resistance breakpoints, although resistance to other β-lactams such as cefuroxime has increased. Multidrug resistance became a serious concern in the treatment of invasive pneumococcal diseases, especially in Asian countries. After PCV7 vaccination, serotype 19A has emerged as an important cause of invasive pneumococcal diseases which was also associated with increasing prevalence of multidrug resistance in pneumococci. Widespread use of PCV13, which covers additional serotypes 3, 6A and 19A, may contribute to reduce the clonal spread of drug-resistant 19A pneumococci.

  8. Resistive switching in TiO{sub 2} thin films

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Lin

    2011-10-26

    The continuing improved performance of the digital electronic devices requires new memory technologies which should be inexpensively fabricated for higher integration capacity, faster operation, and low power consumption. Resistive random access memory has great potential to become the front runner as the non volatile memory technology. The resistance states stored in such cell can remain for long time and can be read out none-destructively by a very small electrical pulse. In this work the typically two terminal memory cells containing a thin TiO{sub 2} layer are studied. Polycrystalline TiO{sub 2} thin films are deposited with atomic layer deposition and magnetron reactive sputtering processes, which are both physically and electrically characterized. The resistive switching cells are constructed in a metal/TiO{sub 2}/metal structure. Electroforming process initiate the cell from the beginning good insulator to a real memory cell to program the resistive states. Multilevel resistive bipolar switching controlled by current compliance is the common characteristic observed in these cells, which is potentially to be used as so called multi-bit memory cells to improve the memory capacity. With different top electrodes of Pt, Cu, Ag the resistive switching behaviors are studied. The switching behaviors are different depending on the top metal such as the minimum current compliance, the endurance of the programmed resistance states and the morphology change during the switching. The temperature dependence of different resistance states are investigated. A reduction of the activation energy and their possible conduction mechanisms is discussed on the base of the basic current conduction models. It is found that the resistance state transfers from semiconductor to metallic property with the reducing resistances. The calculated temperature coefficients of their metallic states on the Cu/TiO{sub 2}/Pt and Ag/TiO{sub 2}/Pt are very close to the reported literature data

  9. Resistive Effects in EXTRAP

    Science.gov (United States)

    Tendler, M.

    1987-02-01

    Theoretical studies of the resistive equilibrium and stability of an EXTRAP Z-pinch are reported. Extending the previous analysis we reassess properties of the resistive equilibrium in EXTRAP with the emphasis on the time dependence of the latter. We also qualitatively consider the role of resistive instabilities in EXTRAP, showing that the typical timescale of the filamentation of the discharge (i.e., the non-linear development of the tearing instability) is comparable, at present, to the discharge duration. On the other hand, we emphasize that this phenomenon may still be consistent with the experimental observation of the Bennet's equilibrium. The processes of the current start-up and ramp-up are also analysed for EXTRAP and it is shown that the peculiarities of these processes may lead to the compression oscillations around an evolving rather stable equilibrium. Finally, some consequences of the average minimum-B concept for EXTRAP are discussed and it is shown that this issue virtually reduces to the appearance of the negative curvature of the magnetic field at the periphery. The maximum attainable value of β at the periphery of the pinch is obtained, as required by the ballooning stability criterion. The influence of the finite resistivity on the ballooning mode is also estimated.

  10. Oseltamivir-Resistant Flu

    Centers for Disease Control (CDC) Podcasts

    2012-04-13

    Dr. Aaron Storms, an Epidemic Intelligence Service (EIS) officer at CDC, discusses his paper about oseltamivir-resistant H1N1flu.  Created: 4/13/2012 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 4/17/2012.

  11. PRESSURE-RESISTANT VESSEL

    NARCIS (Netherlands)

    Beukers, A.; De Jong, T.

    1997-01-01

    Abstract of WO 9717570 (A1) The invention is directed to a wheel-shaped pressure-resistant vessel for gaseous, liquid or liquefied material having a substantially rigid shape, said vessel comprising a substantially continuous shell of a fiber-reinforced resin having a central opening, an inner l

  12. Insulin Resistance and Prediabetes

    Science.gov (United States)

    ... symptoms. Scientists have found that complex interactions in fat tissue draw immune cells to the area and trigger low-level chronic inflammation. This inflammation can contribute to the development of insulin resistance, type 2 diabetes, and CVD. Studies show that losing ...

  13. Fluoroquinolone resistance in Campylobacter

    Science.gov (United States)

    Fluoroquinolone-resistant Campylobacter jejuni and C. coli are common in animals because of the use of fluoroquinolones as therapeutic agents in animal husbandry, particularly in chickens and other poultry. Campylobacter is a commensal in poultry, and therefore, poultry and poultry products are the...

  14. Impact resistant electrolytes

    Energy Technology Data Exchange (ETDEWEB)

    Veith, Gabriel M.; Armstrong, Beth L.; Tenhaeff, Wyatt E.; Dudney, Nancy J.

    2017-03-07

    A passively impact resistant composite electrolyte composition includes an electrolyte solvent, up to 2M of an electrolyte salt, and shear thickening ceramic particles having a polydispersity index of no greater than 0.1, an average particle size of in a range of 50 nm to 1 .mu.m, and an absolute zeta potential of greater than .+-.40 mV.

  15. Antibiotic Resistance and Fungus

    Centers for Disease Control (CDC) Podcasts

    2017-02-28

    Dr. David Denning, President of the Global Action Fund for Fungal Infections and an infectious diseases clinician, discusses antimicrobial resistance and fungus.  Created: 2/28/2017 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 2/28/2017.

  16. Antibiotic-Resistant Bacteria.

    Science.gov (United States)

    Longenecker, Nevin E.; Oppenheimer, Dan

    1982-01-01

    A study conducted by high school advanced bacteriology students appears to confirm the hypothesis that the incremental administration of antibiotics on several species of bacteria (Escherichia coli, Staphylococcus epidermis, Bacillus sublitus, Bacillus megaterium) will allow for the development of antibiotic-resistant strains. (PEB)

  17. Supporting IDP resistance strategies

    Directory of Open Access Journals (Sweden)

    Poe Shan K Phan

    2008-01-01

    Full Text Available Whether in hiding or living under military control, displacedvillagers of Karen State and other areas of rural Burmahave shown themselves to be innovative and courageousin responding to and resisting military abuse. Theyurgently need increased assistance but it is they whoshould determine the direction of any such intervention.

  18. Computational Analysis of Behavior.

    Science.gov (United States)

    Egnor, S E Roian; Branson, Kristin

    2016-07-01

    In this review, we discuss the emerging field of computational behavioral analysis-the use of modern methods from computer science and engineering to quantitatively measure animal behavior. We discuss aspects of experiment design important to both obtaining biologically relevant behavioral data and enabling the use of machine vision and learning techniques for automation. These two goals are often in conflict. Restraining or restricting the environment of the animal can simplify automatic behavior quantification, but it can also degrade the quality or alter important aspects of behavior. To enable biologists to design experiments to obtain better behavioral measurements, and computer scientists to pinpoint fruitful directions for algorithm improvement, we review known effects of artificial manipulation of the animal on behavior. We also review machine vision and learning techniques for tracking, feature extraction, automated behavior classification, and automated behavior discovery, the assumptions they make, and the types of data they work best with.

  19. Behavior Management: Examining the Functions of Behavior

    Science.gov (United States)

    Alstot, Andrew E.; Alstot, Crystal D.

    2015-01-01

    Appropriate student behavior is essential for the success of a physical education lesson. Despite using effective proactive management strategies, teachers may need to also use reactive techniques to reduce problem behaviors by applying suitable consequences. For these consequences to be effective, they must be aligned with the function, or cause,…

  20. Modeling of Agent Behavior Using Behavioral Specifications

    NARCIS (Netherlands)

    Sharpanskykh, A.; Treur, J.

    2006-01-01

    The behavioral dynamics of a cognitive agent can be considered both from an external and an internal perspective. From the external perspective, behavior is described by specifying (temporal) correlations between input and output states of the agent. From the internal perspective the agent’s dynamic

  1. Behaviorism and Cognitivism in Behavior Therapy.

    Science.gov (United States)

    Levis, Donald J.

    The movement within behavior therapy to introduce cognitive terms, constructs, and techniques reflects and involves an extension of the pervasive cognitive movement within the experimental field and the long-standing cognitive approach of many clinicians. Modern day attacks on behaviorism by cognitivists have been almost exclusively geared to the…

  2. Exercise training in the management of patients with resistant hypertension

    Institute of Scientific and Technical Information of China (English)

    Fernando; Ribeiro; Rui; Costa; José; Mesquita-Bastos

    2015-01-01

    Hypertension is a very prevalent risk factor for cardiovascular disease. The prevalence of resistant hypertension, i.e., uncontrolled hypertension with 3 or more antihypertensive agents including 1 diuretic, is between 5% and 30% in the hypertensive population. The causes of resistant hypertension are multifactorial and include behavioral and biological factors, such as nonadherence to pharmacological treatment. All current treatment guidelines highlight the positive role of physical exercise as a non-pharmacological tool in the treatment of hypertension. This paper draws attention to the possible role of physical exercise as an adjunct non-pharmacological tool in the management of resistant hypertension. A few studies have investigated it, employing different methodologies, and taken together they have shown promising results. In summary, the available evidence suggests that aerobic physical exercise could be a valuable addition to the optimal pharmacological treatment of patients with resistant hypertension.

  3. Testing and Modeling of Machine Properties in Resistance Welding

    DEFF Research Database (Denmark)

    Wu, Pei

    electrode force, and the time of stabilizing does not depend on the level of the force. An additional spring mounted in the welding head improves the machine touching behavior due to a soft electrode application, but this results in longer time of oscillation of the electrode force, especially when......The objective of this work has been to test and model the machine properties including the mechanical properties and the electrical properties in resistance welding. The results are used to simulate the welding process more accurately. The state of the art in testing and modeling machine properties...... in resistance welding has been described based on a comprehensive literature study. The present thesis has been subdivided into two parts: Part I: Mechanical properties of resistance welding machines. Part II: Electrical properties of resistance welding machines. In part I, the electrode force in the squeeze...

  4. Resistive switching memory based on bioinspired natural solid polymer electrolytes.

    Science.gov (United States)

    Raeis Hosseini, Niloufar; Lee, Jang-Sik

    2015-01-27

    A solution-processed, chitosan-based resistive-switching memory device is demonstrated with Pt/Ag-doped chitosan/Ag structure. The memory device shows reproducible and reliable bipolar resistive switching characteristics. A memory device based on natural organic material is a promising device toward the next generation of nonvolatile nanoelectronics. The memory device based on chitosan as a natural solid polymer electrolyte can be switched reproducibly between high and low resistance states. In addition, the data retention measurement confirmed the reliability of the chitosan-based nonvolatile memory device. The transparent Ag-embedded chitosan film showed an acceptable and comparable resistive switching behavior on the flexible plastic substrate as well. A cost-effective, environmentally benign memory device using chitosan satisfies the functional requirements of nonvolatile memory operations.

  5. Adipokines mediate inflammation and insulin resistance

    Directory of Open Access Journals (Sweden)

    Jeffrey E. Pessin

    2013-06-01

    Full Text Available For many years, adipose tissue was considered as an inert energy storage organ that accumulates and stores triacylglycerols during energy excess and releases fatty acids in times of systemic energy need. However, over the last two decades adipose tissue depots have been established as highly active endocrine and metabolically important organs that modulate energy expenditure and glucose homeostasis. In rodents, brown adipose tissue plays an essential role in non-shivering thermogenesis and in energy dissipation that can serve to protect against diet-induced obesity. White adipose tissue collectively referred too as either subcutaneous or visceral adipose tissue is responsible for the secretion of an array of signaling molecules, termed adipokines. These adipokines function as classic circulating hormones to communicate with other organs including brain, liver, muscle, the immune system and adipose tissue itself. The dysregulation of adipokines has been implicated in obesity, type 2 diabetes and cardiovascular disease. Recently, inflammatory responses in adipose tissue have been shown as a major mechanism to induce peripheral tissue insulin resistance. Although leptin and adiponectin regulate feeding behavior and energy expenditure, these adipokines are also involved in the regulation of inflammatory responses. Adipose tissue secrete various pro- and anti-inflammatory adipokines to modulate inflammation and insulin resistance. In obese humans and rodent models, the expression of pro-inflammatory adipokines is enhanced to induce insulin resistance. Collectively, these findings have suggested that obesity-induced insulin resistance may result, at least in part, from an imbalance in the expression of pro- and anti-inflammatory adipokines. Thus we will review the recent progress regarding the physiological and molecular functions of adipokines in the obesity-induced inflammation and insulin resistance with perspectives on future directions.

  6. Corrosion behavior of Ti–39Nb alloy for dentistry

    Energy Technology Data Exchange (ETDEWEB)

    Fojt, Jaroslav, E-mail: fojtj@vscht.cz [Institute of Chemical Technology, Technicka 5, 166 28 Prague (Czech Republic); Joska, Ludek [Institute of Chemical Technology, Technicka 5, 166 28 Prague (Czech Republic); Malek, Jaroslav [UJP Praha, Nad Kamínkou 1345, 156 10 Prague-Zbraslav (Czech Republic); Sefl, Vaclav [Institute of Chemical Technology, Technicka 5, 166 28 Prague (Czech Republic)

    2015-11-01

    To increase an orthopedic implant's lifetime, researchers are now concerned on the development of new titanium alloys with suitable mechanical properties (low elastic modulus–high fatigue strength), corrosion resistance and good workability. Corrosion resistance of the newly developed titanium alloys should be comparable with that of pure titanium. The effect of medical preparations containing fluoride ions represents a specific problem related to the use of titanium based materials in dentistry. The aim of this study was to determine the corrosion behavior of β titanium alloy Ti–39Nb in physiological saline solution and in physiological solution containing fluoride ions. Corrosion behavior was studied using standard electrochemical techniques and X-ray photoelectron spectroscopy. It was found that corrosion properties of the studied alloy were comparable with the properties of titanium grade 2. The passive layer was based on the oxides of titanium and niobium in several oxidation states. Alloying with niobium, which was the important part of the alloy passive layer, resulted in no significant changes of corrosion behavior. In the presence of fluoride ions, the corrosion resistance was higher than the resistance of titanium. - Highlights: • Alloy Ti–39Nb shows excellent corrosion resistance in physiological solution. • Corrosion resistance of Ti–39Nb alloy is significantly higher than that of titanium in the presence of fluoride ions. • The electrochemical impedance spectroscopy indicates a porous passive layer. • Passive layer of the alloy is enriched by niobium.

  7. A review of control methods and resistance mechanisms in stored-product insects.

    Science.gov (United States)

    Boyer, S; Zhang, H; Lempérière, G

    2012-04-01

    This review describes the major stored-product insect species and their resistance to insecticides. The economic importance of the control of those pests is highlighted with a loss of more than one billion US dollars per year worldwide. A detailed common description of species resistance throughout the world has been developed, and we observed 28 recurrent studied species involved in resistance cases disseminated on the five continents. The different mechanisms, including behavioral resistance, were studied particularly on Oryzaephilus surinamensis. The role of detoxifying enzymes and studies on the genetic resistance, involving the kdr mutation mechanisms and the transmission of the genes of resistance, are also described. A chapter clarifying definitions on cross and multiple resistance is enclosed.

  8. Recovery of electrical resistance in copper films on polyethylene terephthalate subjected to a tensile strain

    Energy Technology Data Exchange (ETDEWEB)

    Glushko, O. [Department Materials Physics, Montanuniversität Leoben, Jahnstrasse 12, 8700 Leoben (Austria); Marx, V.M.; Kirchlechner, C. [Department Materials Physics, Montanuniversität Leoben, Jahnstrasse 12, 8700 Leoben (Austria); Max-Plank-Institut für Eisenforschung GmbH, Max-Planck-Strasse 1, 40237 Düsseldorf (Germany); Zizak, I. [Helmholtz-Zentrum Berlin for Materials and Energy, Albert-Einstein-Str. 15, D-12489 Berlin (Germany); Cordill, M.J. [Department Materials Physics, Montanuniversität Leoben, Jahnstrasse 12, 8700 Leoben (Austria); Erich Schmid Institute of Materials Science, Austrian Academy of Sciences, Jahnstrasse 12, 8700 Leoben (Austria)

    2014-02-03

    Substantial recovery (decrease) of electrical resistance during and after unloading is demonstrated for copper films on polyethylene terephthalate substrates subjected to a tensile strain with different peak values. Particularly, the films strained to 5% exhibit full resistance recovery after unloading despite clearly visible plastic deformation of the film. The recovery of electrical resistance in connection with the mechanical behavior of film/substrate couple is discussed with the help of in situ scanning electron microscopy and X-ray diffraction analysis. - Highlights: • Tensile tests on 200 nm Cu films on PET substrate are performed. • Electrical resistance is recorded in-situ during loading and unloading. • Significant recovery (decrease) of resistance is observed during and after unloading. • Films strained to 5% demonstrate full resistance recovery. • Viscoelastic relaxation of PET is responsible for recovery of Cu film resistance.

  9. Are Sewage Treatment Plants Promoting Antibiotic Resistance?

    Science.gov (United States)

    1. Introduction 1.1. How bacteria exhibit resistance 1.1.1. Resistance to -lactams 1.1.2. Resistance to sulphonamides and trimethoprim 1.1.3. Resistance to macrolides 1.1.4. Resistance to fluoroquinolones 1.1.5. Resistance to tetracyclines 1.1.6. Resistance to nitroimidaz...

  10. Understanding consumer decisions using behavioral economics.

    Science.gov (United States)

    Zandstra, Elizabeth H; Miyapuram, Krishna P; Tobler, Philippe N

    2013-01-01

    Consumers make many decisions in everyday life involving finances, food, and health. It is known from behavioral economics research that people are often driven by short-term gratification, that is, people tend to choose the immediate, albeit smaller reward. But choosing the delayed reward, that is, delaying the gratification, can actually be beneficial. How can we motivate consumers to resist the "now" and invest in their future, leading to sustainable or healthy habits? We review recent developments from behavioral and neuroimaging studies that are relevant for understanding consumer decisions. Further, we present results from our field research that examined whether we can increase the perceived value of a (delayed) environmental benefit using tailored communication, that is, change the way it is framed. More specifically, we investigated whether we can boost the value of an abstract, long-term "green" claim of a product by expressing it as a concrete, short-term benefit. This is a new application area for behavioral economics.

  11. Interfacial behavior of polymer electrolytes

    Energy Technology Data Exchange (ETDEWEB)

    Kerr, John; Kerr, John B.; Han, Yong Bong; Liu, Gao; Reeder, Craig; Xie, Jiangbing; Sun, Xiaoguang

    2003-06-03

    Evidence is presented concerning the effect of surfaces on the segmental motion of PEO-based polymer electrolytes in lithium batteries. For dry systems with no moisture the effect of surfaces of nano-particle fillers is to inhibit the segmental motion and to reduce the lithium ion transport. These effects also occur at the surfaces in composite electrodes that contain considerable quantities of carbon black nano-particles for electronic connection. The problem of reduced polymer mobility is compounded by the generation of salt concentration gradients within the composite electrode. Highly concentrated polymer electrolytes have reduced transport properties due to the increased ionic cross-linking. Combined with the interfacial interactions this leads to the generation of low mobility electrolyte layers within the electrode and to loss of capacity and power capability. It is shown that even with planar lithium metal electrodes the concentration gradients can significantly impact the interfacial impedance. The interfacial impedance of lithium/PEO-LiTFSI cells varies depending upon the time elapsed since current was turned off after polarization. The behavior is consistent with relaxation of the salt concentration gradients and indicates that a portion of the interfacial impedance usually attributed to the SEI layer is due to concentrated salt solutions next to the electrode surfaces that are very resistive. These resistive layers may undergo actual phase changes in a non-uniform manner and the possible role of the reduced mobility polymer layers in dendrite initiation and growth is also explored. It is concluded that PEO and ethylene oxide-based polymers are less than ideal with respect to this interfacial behavior.

  12. Retroviral superinfection resistance

    Directory of Open Access Journals (Sweden)

    van der Kuyl Antoinette C

    2005-08-01

    Full Text Available Abstract The retroviral phenomenon of superinfection resistance (SIR defines an interference mechanism that is established after primary infection, preventing the infected cell from being superinfected by a similar type of virus. This review describes our present understanding of the underlying mechanisms of SIR established by three characteristic retroviruses: Murine Leukaemia Virus (MuLV, Foamy Virus (FV, and Human Immunodeficiency Virus (HIV. In addition, SIR is discussed with respect to HIV superinfection of humans. MuLV resistant mice exhibit two genetic resistance traits related to SIR. The cellular Fv4 gene expresses an Env related protein that establishes resistance against MuLV infection. Another mouse gene (Fv1 mediates MuLV resistance by expression of a sequence that is distantly related to Gag and that blocks the viral infection after the reverse transcription step. FVs induce two distinct mechanisms of superinfection resistance. First, expression of the Env protein results in SIR, probably by occupancy of the cellular receptors for FV entry. Second, an increase in the concentration of the viral Bet (Between-env-and-LTR-1-and-2 protein reduces proviral FV gene expression by inhibition of the transcriptional activator protein Tas (Transactivator of spumaviruses. In contrast to SIR in FV and MuLV infection, the underlying mechanism of SIR in HIV-infected cells is poorly understood. CD4 receptor down-modulation, a major characteristic of HIV-infected cells, has been proposed to be the main mechanism of SIR against HIV, but data have been contradictory. Several recent studies report the occurrence of HIV superinfection in humans; an event associated with the generation of recombinant HIV strains and possibly with increased disease progression. The role of SIR in protecting patients from HIV superinfection has not been studied so far. The phenomenon of SIR may also be important in the protection of primates that are vaccinated with live

  13. Impact of scarcity on consumer behavior

    Directory of Open Access Journals (Sweden)

    T.U. Kulakovsky

    2016-09-01

    Full Text Available This article analyzes the impact of scarcity on consumer behavior and on perception of scarce goods consumer qualities. The author examines and subjects to the critical analysis the impact of scarcity on consumer behavior within economic theory, the theory of reactance and commodity theory. The differences in explaining the impact of scarcity on consumer behavior in economic and psychological sciences is highlighted. The current researcher experimentally proves the impact of the scarcity as an isolated factor on consumer behavior and the impact of scarcity on consumer perception of product quality. According to the reactance theory, an individual perceives scarcity as the restriction of his freedom that causes resistance in response to a possible restriction of freedom of actions. This reinforces the desire to have such a scarce product. To confirm the psychological impact of scarcity on a domestic consumer the author designs and conducts the experiment that confirms the following hypotheses: scarcity affects consumer behavior and stimulates consumers to purchase scarce commodities; scarcity has impact on the perception of scarce product consumer qualities. Such consumer behavior relatively to scarce goods can be used by marketers to promote products on the market.

  14. Mission Critical: Preventing Antibiotic Resistance

    Science.gov (United States)

    ... Button Past Emails CDC Features Mission Critical: Preventing Antibiotic Resistance Recommend on Facebook Tweet Share Compartir Can you ... spp. So, what can we do to prevent antibiotic resistance in healthcare settings? Patients, healthcare providers, healthcare facility ...

  15. Antibiotic-Resistant Gonorrhea (ARG)

    Science.gov (United States)

    ... Twitter STD on Facebook Sexually Transmitted Diseases (STDs) Antibiotic-Resistant Gonorrhea Basic Information Recommend on Facebook Tweet ... Page Surveillance Trends and Treatment Challenges Laboratory Issues Antibiotic resistance (AR) is the ability of bacteria to ...

  16. Helping Teens Resist Sexual Pressure

    Science.gov (United States)

    ... Listen Español Text Size Email Print Share Helping Teens Resist Sexual Pressure Page Content Article Body Teens ... younger the first time they had intercourse. Helping Teens Resist Sexual Pressure “The pressure on teenagers to ...

  17. Galileo's Trajectory with Mild Resistance

    Science.gov (United States)

    Groetsch, C. W.

    2012-01-01

    An aspect of Galileo's classical trajectory that persists in a simple resistance model is noted. The resistive model provides a case study for the classroom analysis of limiting behaviour of an implicitly defined function. (Contains 1 note.)

  18. Behavior Modification in Coaching.

    Science.gov (United States)

    Lynch, Annette Rutt; Stillman, Stephen M.

    1979-01-01

    An example of behavior modification used in athletic coaching is presented. The case study involves a member of a women's basketball team and details the use of behavior modification for both weight reduction and skill improvement. (JMF)

  19. Humanism vs. Behaviorism

    Science.gov (United States)

    Hunter, Madeline

    1977-01-01

    Author argues that humanism and behaviorism are not necessarily exclusive of one another, and that principles of behaviorism, when thoughtfully applied, can lead to the achievement of humanistic goals. (RW)

  20. Behaviorism and Neuroscience.

    Science.gov (United States)

    Thompson, Richard F.

    1994-01-01

    The influence of behaviorism's methods and theories on theory and research in the neurosciences is examined, partly in light of John B. Watson's 1913 essay. An attempt is made to reconcile classical behaviorism and modern cognitive psychology and neuroscience. (SLD)

  1. Bridging Humanism and Behaviorism.

    Science.gov (United States)

    Chu, Lily

    1980-01-01

    Humanistic behaviorism may provide the necessary bridge between behaviorism and humanism. Perhaps the most humanistic approach to teaching is to learn how certain changes will help students and how these changes can be accomplished. (Author/MLF)

  2. Cognitive behavioral therapy of obsessive-compulsive disorder

    OpenAIRE

    Edna B. Foa

    2010-01-01

    Until the mid-1960s, obsessive-compulsive disorder (OCD) was considered to be treatment-resistant, as both psychodynamic psychotherapy and medication had been unsuccessful in significantly reducing OCD symptoms. The first real breakthrough came in 1966 with the introduction of exposure and ritual prevention. This paper will discuss the cognitive behavioral conceptualizations that influenced the development of cognitive behavioral treatments for OCD. There will be a brief discussion of the use...

  3. Bacterial vaccines and antibiotic resistance

    OpenAIRE

    Henriques-Normark, Birgitta; Normark, Staffan

    2014-01-01

    Spread of antibiotic resistance is mediated by clonal lineages of bacteria that besides being resistant also possess other properties promoting their success. Some vaccines already in use, such as the pneumococcal conjugate vaccines, have had an effect on these successful clones, but at the same time have allowed for the expansion and resistance evolution of previously minor clones not covered by the vaccine. Since resistance frequently is horizontally transferred it will be difficult to gene...

  4. Clopidogrel resistance: The way forward

    OpenAIRE

    Ray, Shuvanan

    2014-01-01

    Clopidogrel, a second generation thienopyridine has been the mainstay of ACS (Acute Coronary Syndrome) treatment for more than a decade. Clopidogrel Resistance has been associated with increased mortality in ACS patients with an increase in number of Stent Thrombosis. This review article tries to find out the causes of Clopidogrel Resistance, the main factors involving it, Laboratory evaluation of Clopidogrel Resistance. The overall incidence of Clopidogrel Resistance across the Globe & India...

  5. Antibacterial resistance: an emerging 'zoonosis'?

    Science.gov (United States)

    Labro, Marie-Thérèse; Bryskier, Jean-Marie

    2014-12-01

    Antibacterial resistance is a worldwide threat, and concerns have arisen about the involvement of animal commensal and pathogenic bacteria in the maintenance and spread of resistance genes. However, beyond the facts related to the occurrence of resistant microorganisms in food, food-producing animals and companion animals and their transmission to humans, it is important to consider the vast environmental 'resistome', the selective pathways underlying the emergence of antibacterial resistance and how we can prepare answers for tomorrow.

  6. Corrosion-resistant metal surfaces

    Science.gov (United States)

    Sugama, Toshifumi

    2009-03-24

    The present invention relates to metal surfaces having thereon an ultrathin (e.g., less than ten nanometer thickness) corrosion-resistant film, thereby rendering the metal surfaces corrosion-resistant. The corrosion-resistant film includes an at least partially crosslinked amido-functionalized silanol component in combination with rare-earth metal oxide nanoparticles. The invention also relates to methods for producing such corrosion-resistant films.

  7. Behaviorism and Society

    OpenAIRE

    Krapfl, Jon E.

    2016-01-01

    A probable list of causes for the limited acceptance of behaviorism in our society is identified. This is followed by a summary review of the proposed solutions identified in other papers in this special issue of The Behavior Analyst, most of which relate to either better marketing of either the behavior analytic process or the results achieved as a consequence. One paper proposes a more broad conception of behavior analysis. This paper endorses the solutions identified in previous papers and...

  8. What determines our behavior

    OpenAIRE

    Marko Radovan

    2001-01-01

    In article Ajzen-Fishbein's attitude-behavior model called 'Theory of reasoned action' and Albert Bandura's Model of reciprocal determinism are presented. Both models are a part of social-cognitive paradigm which characterizes behavior with evaluation of different goals. Ajzen and Fishbein (1973; 1980) proposed that specific behavior are predictable from specific behavioral intentions. These intentions are a function of two components: the attitude toward the act in question a...

  9. Resistance patterns, prevalence, and predictors of fluoroquinolones resistance in multidrug resistant tuberculosis patients

    Directory of Open Access Journals (Sweden)

    Nafees Ahmad

    2016-02-01

    Full Text Available Abstract Background Fluoroquinolones are the backbone of multidrug resistant tuberculosis treatment regimens. Despite the high burden of multidrug resistant tuberculosis in the country, little is known about drug resistance patterns, prevalence, and predictors of fluoroquinolones resistance among multidrug resistant tuberculosis patients from Pakistan. Objective To evaluate drug resistance patterns, prevalence, and predictors of fluoroquinolones resistance in multidrug resistant tuberculosis patients. Methods This was a cross-sectional study conducted at a programmatic management unit of drug resistant tuberculosis, Lady Reading Hospital Peshawar, Pakistan. Two hundred and forty-three newly diagnosed multidrug resistant tuberculosis patients consecutively enrolled for treatment at study site from January 1, 2012 to July 28, 2013 were included in the study. A standardized data collection form was used to collect patients’ socio-demographic, microbiological, and clinical data. SPSS 16 was used for data analysis. Results High degree of drug resistance (median 5 drugs, range 2–8 was observed. High proportion of patients was resistant to all five first-line anti-tuberculosis drugs (62.6%, and more than half were resistant to second line drugs (55.1%. The majority of the patients were ofloxacin resistant (52.7%. Upon multivariate analysis previous tuberculosis treatment at private (OR = 1.953, p = 0.034 and public private mix (OR = 2.824, p = 0.046 sectors were predictors of ofloxacin resistance. Conclusion The high degree of drug resistance observed, particularly to fluoroquinolones, is alarming. We recommend the adoption of more restrictive policies to control non-prescription sale of fluoroquinolones, its rational use by physicians, and training doctors in both private and public–private mix sectors to prevent further increase in fluoroquinolones resistant Mycobacterium tuberculosis strains.

  10. Behavioral Economics and Consumption

    DEFF Research Database (Denmark)

    Reisch, Lucia A.; Sunstein, Cass R.

    2015-01-01

    Behavioral economics explores why people sometimes fail to make rational decisions, and how their behavior departs from the predictions of standard economic models. Insights gained from studies in behavioral economics are used in consumer research and consumer policy to understand and improve...

  11. Consumer Behavior Research Methods

    DEFF Research Database (Denmark)

    Chrysochou, Polymeros

    2017-01-01

    This chapter starts by distinguishing consumer behavior research methods based on the type of data used, being either secondary or primary. Most consumer behavior research studies phenomena that require researchers to enter the field and collect data on their own, and therefore the chapter...... of the methods and how to improve quality in consumer behavior research methods....

  12. Behavioral Strategies: Building Systems.

    Science.gov (United States)

    Sandoz, Charles J.

    Using a construction building analogy, this guide provides a plan for building a system of behavior strategies. These strategies are designed to assist behavior analysts of contracted provider agencies in the construction and maintenance of procedures which will help monitor and reduce the frequency of problematic behaviors in individuals with…

  13. Bad Romance: Sex Differences in the Longitudinal Association Between Romantic Relationships and Deviant Behavior.

    Science.gov (United States)

    Monahan, Kathryn C; Dmitrieva, Julia; Cauffman, Elizabeth

    2014-03-01

    The current study investigates how romantic relationships are related to antisocial behavior longitudinally among delinquent males and females (n=354; ages 14-25). While being in a relationship or not is unrelated to antisocial behavior, romantic partner characteristics (antisocial behavior and antisocial influence) are associated with greater antisocial behavior. As males age, they become increasingly resistant to romantic partner characteristics. In contrast, females become increasingly vulnerable to the effects of romantic partner characteristics on antisocial behavior as they age, particularly when these relationships are relatively shorter. Females in shorter romantic relationships with partners who are antisocial or exert antisocial influence are at risk of persisting in antisocial behavior.

  14. Chemical Countermeasures for Antibiotic Resistance

    Science.gov (United States)

    2014-04-01

    SUPPLEMENTARY NOTES 14.ABSTRACT New approaches are required to control multi-drug resistant (MDR) bacterial infections in military medical facilities ...New approaches are required to control multi-drug resistant (MDR) bacterial infections in military medical facilities , as injured Warfighters...current position: postdoc in the Disney lab TSRI Florida 15 CONCLUSION: New approaches are desperately required to control multi-drug resistant

  15. Biotechnology: herbicide-resistant crops

    Science.gov (United States)

    Transgenic, herbicide-resistant (HR) crops are planted on about 80% of the land covered by transgenic crops. More than 90% of HR crios are glyphosate-resistant (GR) crops, the others being resistant to glufosinate. The wide-scale adoption of HR crops, largely for economic reasons, has been the mos...

  16. Investigating the Antibiotic Resistance Problem.

    Science.gov (United States)

    Lawson, Michael; Lawson, Amy L.

    1998-01-01

    Seeks to give teachers useful information on the extent of the problem of antibiotic-resistant bacteria, mechanisms bacteria use to resist antibiotics, the causes of the emergence of antibiotic-resistant organisms, and practices that can prevent or reverse this trend. Contains 19 references. (DDR)

  17. Driving Resistance from Railroad Trains

    DEFF Research Database (Denmark)

    Lindgreen, Erik Bjørn Grønning; Sorenson, Spencer C

    2005-01-01

    This report methods and parameters for calculating the driving resistance of railroad trains. Calculations and comparisons are presented for aerodynamic, rolling and total resistance for a variety of freight trains under different loading conditions, operating speed and configuration. Simplified...... methods are presented for the estimation of the driving resistance for passenger trains. This report is a supplement to the ARTEMIS rail emissions model....

  18. Studying Resistance: Some Cautionary Notes

    Science.gov (United States)

    Dimitriadis, Greg

    2011-01-01

    The question of "resistance" has oriented the field of critical ethnography for several generations now. Indeed, the reproduction-resistance binary has animated much of the most important, critical work in educational studies over the last 30 years. Yet, this reproduction-resistance binary has perhaps calcified in recent years. Such work often…

  19. Testing Tools for Glyphosate Resistance

    Science.gov (United States)

    There are multiple tools available for testing for glyphosate resistance. Whole plant screens, whether in the field or greenhouse, should be used as an initial method to determine if a biotype is glyphosate resistant. Screening for resistance using seedling assays such as in Petri plates, sand cul...

  20. Studying Resistance: Some Cautionary Notes

    Science.gov (United States)

    Dimitriadis, Greg

    2011-01-01

    The question of "resistance" has oriented the field of critical ethnography for several generations now. Indeed, the reproduction-resistance binary has animated much of the most important, critical work in educational studies over the last 30 years. Yet, this reproduction-resistance binary has perhaps calcified in recent years. Such work…

  1. Insecticide Resistance Management

    Science.gov (United States)

    2013-01-01

    thuringiensis var. membranes israeknsis A2 Bacillus sphaencus Inhibitocs of chitin biosynthesis type 0 15 Benzaylureas Diflubenzuron, triflnmuron...resistance can detoxify or destroy the pesticide toxins at a faster rate, break down the toxins inside the body, and/or prevent the pesticide from entering...hocmone analogues MethOJre!le, hydorpene Juvenile hormone mimics 7 c Pyri proxyfen Pyriproxyfen Microbial disrupters of insect midgut 11 AI Bacillus

  2. Insulin and Insulin Resistance

    OpenAIRE

    Wilcox, Gisela

    2005-01-01

    As obesity and diabetes reach epidemic proportions in the developed world, the role of insulin resistance and its consequences are gaining prominence. Understanding the role of insulin in wide-ranging physiological processes and the influences on its synthesis and secretion, alongside its actions from the molecular to the whole body level, has significant implications for much chronic disease seen in Westernised populations today. This review provides an overview of insulin, its history, stru...

  3. Multidrug-Resistant Tuberculosis

    Centers for Disease Control (CDC) Podcasts

    2008-10-28

    In this podcast, Dr. Oeltmann discusses multidrug-resistant tuberculosis. An outbreak occurred in Thailand, which led to 45 cases in the U.S. This serious illness can take up to 2 years to treat. MDR TB is a real threat and a serious condition.  Created: 10/28/2008 by Emerging Infectious Diseases.   Date Released: 10/28/2008.

  4. Engineering disease resistant cattle.

    Science.gov (United States)

    Donovan, David M; Kerr, David E; Wall, Robert J

    2005-10-01

    Mastitis is a disease of the mammary gland caused by pathogens that find their way into the lumen of the gland through the teat canal. Mammary gland infections cost the US dairy industry approximately $2 billion dollars annually and have a similar impact in Europe. In the absence of effective treatments or breeding strategies to enhance mastitis resistance, we have created transgenic dairy cows that express lysostaphin in their mammary epithelium and secrete the antimicrobial peptide into milk. Staphylococcus aureus, a major mastitis pathogen, is exquisitely sensitive to lysostaphin. The transgenic cattle resist S. aureus mammary gland challenges, and their milk kills the bacteria, in a dose dependent manner. This first step in protecting cattle against mastitis will be followed by introduction of other genes to deal with potential resistance issues and other mastitis causing organisms. Care will be taken to avoid altering milk's nutritional and manufacturing properties. Multi-cistronic constructs may be required to achieve our goals as will other strategies possibly involving RNAi and gene targeting technology. This work demonstrates the possibility of using transgenic technology to address disease problems in agriculturally important species.

  5. Herbicide resistance screening assay.

    Science.gov (United States)

    Peterson, Joan M

    2009-01-01

    Herbicide resistance screening is a method that can be used not only to determine presence of the enzyme, phosphinothricin acetyltransferase, encoded by either the Bar or the Pat gene in transgenic maize, but also to assess the inheritance ratio of those genes in a segregating population. Herbicide screening can also be used to study linkage of a transgene of interest that was cotransformed with the herbicide resistance marker gene. By combining the herbicide screen assay with a PCR-based screen of leaf tissue DNA for the presence of both the Bar or the Pat gene marker and a cotransformed transgene of interest from the same seedling tissue and maintaining that seedling identity, the researcher can identify linkage or the possible breakdown in linkage of the marker gene and the transgene of interest. Further, the occurrence of "DNA silencing" can be evaluated if an individual seedling that was susceptible to the applied herbicide nonetheless gave PCR data that indicated presence of the gene responsible for herbicide resistance. Similarly, "DNA silencing" of the gene of interest may be investigated if the seeds can be screened and scored for that phenotypic trait in a nondestructive manner prior to planting.

  6. Do Fish Resist?

    Directory of Open Access Journals (Sweden)

    Dinesh Joseph Wadiwel

    2016-03-01

    Full Text Available There have been a number of scientific studies on the question of whether fish feel pain. Some have suggested that some fish indeed do feel pain and that this has significant welfare implications (2003. Others have argued that fish do not have the brain development necessary to feel pain. In terms of number of animals killed, the slaughter of sea animals for human consumption significantly exceeds that of any land animals that we use for food, and sea animal slaughter practices frequently lack any basic welfare protections. If fish can be shown to feel pain—or more importantly, if humans can agree that fish feel pain—then this would place a significant question mark over many contemporary fishing practices.  This article substitutes the question 'Do Fish Feel Pain?' with an alternative: 'Do Fish Resist?' It explores the conceptual problems of understanding fish resistance, and the politics of epistemology that surrounds and seeks to develop a conceptual framework for understanding fish resistance to human capture by exploring the development of fishing technologies - the hook, the net and contemporary aquaculture.

  7. Resistant Hypertension and Chronotherapy

    Science.gov (United States)

    Prkacin, Ingrid; Balenovic, Diana; Djermanovic-Dobrota, Vesna; Lukac, Iva; Drazic, Petra; Pranjic, Iva-Klara

    2015-01-01

    Resistant hypertension is defined as blood pressure that remains above 140/90 mmHg in spite of the continuous use of three antihypertensive agents in optimal dose, including diuretic, and lifestyle changes. According to data from United States of America and Europe, the prevalence ranges from 10 up to 30% in patients with hypertension. Numerous biological and lifestyle factors can contribute to the development of resistant hypertension: medications, volume overload, obesity, diabetes mellitus, older age, renal parenchymal and renovascular disease, primary aldosteronism, obstructive sleep apnea, pheochormocytoma, Cushing’s syndrome, thyroid diseases, aortic coarctation. For diagnosing patient’s history is important, assessing compliance, regular blood pressure measurement, physical examination, biochemical evaluation and noninvasive imaging. The evaluation including 24h ambulatory monitoring of blood pressure (ABPM) in the identification of “non-dipper” hypertension. Non-dipper has particular importance and the prevalence of abnormally high sleep blood pressure is very often in chronic kidney patients. Therapeutic restoration of normal physiologic blood pressure reduction during night-time sleep (circadial variation) is the most significant independent predictor of decreased risk and the basis for the chronotherapy. The resistant hypertension treatment is achieved with nonpharmacological and pharmacological approach, treating secondary hypertension causes and invasive procedures. PMID:26005390

  8. Resisting protein adsorption on biodegradable polyester brushes.

    Science.gov (United States)

    Hu, Xinfang; Gorman, Christopher B

    2014-08-01

    The protein adsorption and degradation behaviors of poly(lactic acid), poly(glycolic acid) (PGA) and poly(ε-caprolactone) (PCL) brushes and their co-polymer brushes with oligo(ethylene glycol) (OEG) were studied. Both brush structure and relative amount of OEG and polyester were found to be important to the protein resistance of the brushes. A protein-resisting surface can be fabricated either by using OEG as the top layer of a copolymer brush or by increasing the amount of OEG relative to polyester when using a hydroxyl terminated OEG (OEG-OH) and a methoxy terminated OEG (OEG-OMe) mixture as the substrate layer. The degradation of single polyester brushes and their co-polymer brushes using OEG-OH as a substrate layer or using OEG as a top layer was hindered. This phenomenon was rationalized by the inhibition of the proposed back-biting process as the hydroxy end groups of polyester were blocked by OEG molecules. Among these brushes tested, PGA co-polymer brushes using the methoxy/hydroxyl OEG mixture as the substrate layer proved to be both protein-resistant and degradable due to the relatively large amount of OEG moieties and the good biodegradability of PGA.

  9. A case illustration of resistance from a gestalt-experiential perspective.

    Science.gov (United States)

    Engle, David; Holiman, Marjorie

    2002-02-01

    The case of Victoria illustrates psychotherapy with a woman faced with a difficult and unexpected divorce. The authors present a summary of typical struggles faced by Victoria through three phases of therapy. The therapy focused initially on coping with the divorce, then moved to work on her career dissatisfaction, and finally to her efforts to develop a new relationship. The case presentation illustrates resistance as it manifested itself in both a behavioral manner and as in-session resistance to awareness of internal states. The behavioral mode of resistance is manifested by her inability to follow through on decisions made in therapy sessions and by her interruptions of ongoing therapy. A transcript of a typical in-session exchange illustrates the resistance to awareness. The authors also describe interventions intended to work with the resistance.

  10. Breast Cancer Resistance Protein Expression and 5-Fluorouracil Resistance

    Institute of Scientific and Technical Information of China (English)

    JIAN-HUI YUAN; ZHI-XIONG ZHUANG; JIN-QUAN CHENG; LONG-YUAN JIANG; WEI-DONG JI; LIANG-FENG GUO; JIAN-JUN LIU; XING-YUN XU; JING-SONG HE; XIAN-MING WANG

    2008-01-01

    To filtrate breast cancer resistance protein (BCRP)-mediated resistant agents and to investigate clinical relationship between BCRP expression and drug resistance. Methods MTT assay was performed to filtrate BCRP-mediated resistant agents with BCRP expression cell model and to detect chemosensitivity of breast cancer tissue specimens to these agents. A high performance liquid chromatography (HPLC) assay was established, and was used to measure the relative dose of intracellular retention resistant agents. RT-PCR and immununohistochemistry (IHC) were employed to investigate the BCRP expression in breast cancer tissue specimens. Results MTT assay showed that the expression of BCRP increased with the increasing resistance of 5-fluorouracil (5-Fu) (P=0.8124, P<0.01). Condusion Resistance to 5-Fu can be mediated by BCRP. Clinical chemotherapy for breast cancer patients can be optimized based on BCRP-positive expression.

  11. HDAC3-selective inhibitor enhances extinction of cocaine-seeking behavior in a persistent manner

    OpenAIRE

    Malvaez, Melissa; McQuown, Susan C; Rogge, George A.; Astarabadi, Mariam; Jacques, Vincent; Carreiro, Samantha; Rusche, James R.; Wood, Marcelo A.

    2013-01-01

    Nonspecific histone deacetylase (HDAC) inhibition has been shown to facilitate the extinction of drug-seeking behavior in a manner resistant to reinstatement. A key open question is which specific HDAC is involved in the extinction of drug-seeking behavior. Using the selective HDAC3 inhibitor RGFP966, we investigated the role of HDAC3 in extinction and found that systemic treatment with RGFP966 facilitates extinction in mice in a manner resistant to reinstatement. We also investigated whether...

  12. Study on Relationship Between Halothane Gene and Behavioral Stereotypies in Pregnant Sows

    Institute of Scientific and Technical Information of China (English)

    CUI Wei-guo; LI Jian-hong; BAO Jun

    2003-01-01

    A simple preparation using the ear tissue for PCR amplification was established for diagnosis of genotypes for halothane in 181 sows.3 halothane heterozygous pigs were detected.The behaviors of the sows that have different genotypes were observed.The heterozygous sows expressed seem more behavioral stereotypies than halothane resistant.But there is no difference in two genotypes.The behaviour directed trough in heterozygous sows is higher than halothane resistant.

  13. Forming-free and hard-breakdown depressed resistive switching based on natural conductive path

    Science.gov (United States)

    Duan, W. J.; Wang, J. B.; Zhong, X. L.; Song, H. J.; Li, B.

    2017-03-01

    A forming-free, compliance-current needless and hard-breakdown depressed resistive switching is demonstrated in Cu2O film. Different from the conventional resistive switching behaviors, this reversible switch is free from the forming process, and does not dependent on the direction of the initial electric field. The resistive switching effect may be triggered by the break and recovery of natural conductive path, and a dynamic model is proposed to explain the switching process. Meanwhile, the influence of degradation in local region is also discussed, which is important for switching mechanism understanding. These results are an important step towards the development of resistive switching devices and their applications.

  14. Predicting Sustainable Work Behavior

    DEFF Research Database (Denmark)

    Hald, Kim Sundtoft

    2013-01-01

    Sustainable work behavior is an important issue for operations managers – it has implications for most outcomes of OM. This research explores the antecedents of sustainable work behavior. It revisits and extends the sociotechnical model developed by Brown et al. (2000) on predicting safe behavior....... Employee characteristics and general attitudes towards safety and work condition are included in the extended model. A survey was handed out to 654 employees in Chinese factories. This research contributes by demonstrating how employee- characteristics and general attitudes towards safety and work...... condition influence their sustainable work behavior. A new definition of sustainable work behavior is proposed....

  15. Molecular mechanisms of antibiotic resistance.

    Science.gov (United States)

    Blair, Jessica M A; Webber, Mark A; Baylay, Alison J; Ogbolu, David O; Piddock, Laura J V

    2015-01-01

    Antibiotic-resistant bacteria that are difficult or impossible to treat are becoming increasingly common and are causing a global health crisis. Antibiotic resistance is encoded by several genes, many of which can transfer between bacteria. New resistance mechanisms are constantly being described, and new genes and vectors of transmission are identified on a regular basis. This article reviews recent advances in our understanding of the mechanisms by which bacteria are either intrinsically resistant or acquire resistance to antibiotics, including the prevention of access to drug targets, changes in the structure and protection of antibiotic targets and the direct modification or inactivation of antibiotics.

  16. Nonlinear Resistivity for Magnetohydrodynamical Models

    CERN Document Server

    Lingam, Manasvi; Pfefferlé, David; Comisso, Luca; Bhattacharjee, Amitava

    2016-01-01

    A nonlinear current-dependent resistivity that accurately accounts for the collisional electron-ion momentum transfer rate is derived. It is shown that the Spitzer resistivity overestimates the resistivity in certain observationally relevant regimes. The nonlinear resistivity computed herein is a strictly decreasing function of the current, in contrast to some notable previous proposals. The relative importance of the new expression with respect to the well-established electron inertia and Hall terms is also examined. The subtle implications of this current-dependent resistivity are discussed in the context of plasma systems and phenomena such as magnetic reconnection.

  17. Antimicrobial resistance of thermophilic Campylobacter

    DEFF Research Database (Denmark)

    Aarestrup, Frank Møller; Engberg, J.

    2001-01-01

    Campylobacter has become the leading cause of zoonotic enteric infections in developed and developing countries world-wide. Antimicrobial resistance has emerged among Campylobacter mainly as a consequence of the use of antimicrobial agents in food animal production. Resistance to drugs of choice...... for the treatment of infections, macrolides and fluoroquinolones has emerged as a clinical problem and interventions to reduce this are recommended. Resistance to fluoroquinolones and macrolides is mediated by chromosomal mutations. Resistance to other relevant antimicrobial agents, mediated by acquired resistance...

  18. Understanding dissolution behavior of 193nm photoresists in organic solvent developers

    Science.gov (United States)

    Lee, Seung-Hyun; Park, Jong Keun; Cardolaccia, Thomas; Sun, Jibin; Andes, Cecily; O'Connell, Kathleen; Barclay, George G.

    2012-03-01

    Herein, we investigate the dissolution behavior of 193-nm chemically amplified resist in different organic solvents at a mechanistic level. We previously reported the effect of solvent developers on the negative tone development (NTD) process in both dry and immersion lithography, and demonstrated various resist performance parameters such as photospeed, critical dimension uniformity, and dissolution rate contrast are strongly affected by chemical nature of the organic developer. We further pursued the investigation by examining the dependence of resist dissolution behavior on their solubility properties using Hansen Solubility Parameter (HSP). The effects of monomer structure, and resist composition, and the effects of different developer chemistry on dissolution behaviors were evaluated by using laser interferometry and quartz crystal microbalance. We have found that dissolution behaviors of methacrylate based resists are significantly different in different organic solvent developers such as OSDTM-1000 Developer* and n-butyl acetate (nBA), affecting their resist performance. This study reveals that understanding the resist dissolution behavior helps to design robust NTD materials for higher resolution imaging.

  19. Quantum Resistive Transition in Type II Superconductors under Magnetic Field

    CERN Document Server

    Ikeda, R

    1995-01-01

    It is shown that, within a Ginzburg-Landau (GL) formalism, the superconducting fluctuation is insulating at zero temperature even if the fluctuation dynamics is metallic (dissipative). Based on this fact, the low temperature behavior of the $H_{c2}$-line and the resistivity curves near a zero temperature transition are discussed. In particular, it is pointed out that the neglect of quantum fluctuations in data analysis of the dc resistivity may lead to an under-estimation of the $H_{c2}$ values near zero temperature.

  20. Behaviorism and Society.

    Science.gov (United States)

    Krapfl, Jon E

    2016-05-01

    A probable list of causes for the limited acceptance of behaviorism in our society is identified. This is followed by a summary review of the proposed solutions identified in other papers in this special issue of The Behavior Analyst, most of which relate to either better marketing of either the behavior analytic process or the results achieved as a consequence. One paper proposes a more broad conception of behavior analysis. This paper endorses the solutions identified in previous papers and then goes on to propose an even more broad conception of behavior analysis and makes the point that behavior analysis is unlikely to flourish unless behavior analysts understand a good deal more about the cultural and other contextual features of the environments in which they work.

  1. Behavioral Immunity in Insects

    Directory of Open Access Journals (Sweden)

    Thierry Lefèvre

    2012-08-01

    Full Text Available Parasites can dramatically reduce the fitness of their hosts, and natural selection should favor defense mechanisms that can protect hosts against disease. Much work has focused on understanding genetic and physiological immunity against parasites, but hosts can also use behaviors to avoid infection, reduce parasite growth or alleviate disease symptoms. It is increasingly recognized that such behaviors are common in insects, providing strong protection against parasites and parasitoids. We review the current evidence for behavioral immunity in insects, present a framework for investigating such behavior, and emphasize that behavioral immunity may act through indirect rather than direct fitness benefits. We also discuss the implications for host-parasite co-evolution, local adaptation, and the evolution of non-behavioral physiological immune systems. Finally, we argue that the study of behavioral immunity in insects has much to offer for investigations in vertebrates, in which this topic has traditionally been studied.

  2. Analysis of Autopilot Behavior

    Science.gov (United States)

    Sherry, Lance; Polson, Peter; Feay, Mike; Palmer, Everett; Null, Cynthia H. (Technical Monitor)

    1998-01-01

    Aviation and cognitive science researchers have identified situations in which the pilot's expectations for behavior of autopilot avionics are not matched by the actual behavior of the avionics. These "automation surprises" have been attributed to differences between the pilot's model of the behavior of the avionics and the actual behavior encoded in the avionics software. A formal technique is described for the analysis and measurement of the behavior of the cruise pitch modes of a modern Autopilot. The analysis characterizes the behavior of the Autopilot as situation-action rules. The behavior of the cruise pitch mode logic for a contemporary modern Autopilot was found to include 177 rules, including Level Change (23), Vertical Speed (16), Altitude Capture (50), and Altitude Hold (88). These rules are determined based on the values of 62 inputs. Analysis of the rule-based model also shed light on the factors cited in the literature as contributors to "automation surprises."

  3. The Psychic Life of Resistance

    DEFF Research Database (Denmark)

    Barinaga, Ester

    2013-01-01

    to power. This article is a first step to remedy that oversight. Inspired by Butler’s reading of Foucault’s notion of power at work in subjection and resistance, the article uses Goffman to substantiate such an account. Based on a 20-month ethnographic study of a traditional immigrant suburb north......The last 20 years have seen a flood of studies of resistance, ranging from collective to individual acts of resistance, from the study of material aspects to its more ideational ones. Yet students of resistance have neglected the psychological dimension of everyday individual acts of resistance...... of Stockholm, Sweden, which is being redeveloped into a high-tech region, it offers empirical insight into the psychic life of resistance. Further, a particular resistance strategy is identified: symbolic dislocations through adherence to a boundary other than the one subjecting the self in the first place....

  4. Controlling antibiotic resistance in the ICU

    NARCIS (Netherlands)

    Derde, L.P.G.

    2013-01-01

    Patients admitted to intensive care units (ICUs) are frequently colonized with (antibiotic-resistant) bacteria, which may lead to healthcare associated infections. Antimicrobial-resistant bacteria (AMRB), such as methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant Enterococci (V

  5. Happy Festivus! Parody as playful consumer resistance

    DEFF Research Database (Denmark)

    Mikkonen, Ilona; Bajde, Domen

    2013-01-01

    Drawing upon literary theory, play and consumer resistance literature, we conceptualize consumer parodic resistance – a resistant form of play that critically refunctions dominant consumption discourses and marketplace ideologies. We explore parodic resistance empirically by analyzing Festivus...

  6. Treatment Resistant Hypertension.

    Science.gov (United States)

    Egan, Brent M

    2015-11-05

    Treatment resistant hypertension (TRH) is defined by office blood pressure (BP) uncontrolled on ≥ 3 or controlled on ≥ 4 antihypertensive medications, preferably at optimal doses and including a diuretic. Apparent (a)TRH is used when optimal therapy, adherence, and measurement artifacts are unknown. Among treated hypertensives, ~30% of uncontrolled and 10% of controlled individuals have aTRH, with a higher prevalence in Blacks than other race-ethnicity groups. In ≥ 50% of aTRH patients, BP measurement artifacts ('office' TRH), suboptimal regimens, or suboptimal adherence are present, ie, pseudo-resistance. While patients with 'office' TRH have fewer cardiovascular events than those with 'true' TRH, no evidence confirms that patients with suboptimal regimens or adherence are spared. Averaging several office BPs obtained with an automated monitor can reduce 'office' TRH. Home or ambulatory BP monitoring can identify office resistance. Prescribing ≥ 3 different antihypertensive medication classes, eg, thiazide-type diuretic, renin-angiotensin blocker and calcium antagonist at ≥ 50% of maximum recommended doses reasonably defines optimal therapy. Intensifying diuretic therapy, eg, adding an aldosterone antagonist, is effective for many TRH patients who are volume expanded. Clinical information, hemodynamic and renin-guided therapeutics can inform other treatment options. Attention to adverse effects, medication costs, and pill burden can improve adherence and control. Patients with aTRH and suspected secondary hypertension should be evaluated. Interfering substances or medications should be discontinued. These approaches will identify or correct the problem in ~80% of aTRH patients. Referral to a hypertension specialist and newer therapeutic approaches are options for TRH patients who cannot take or do not respond to optimal therapy.

  7. Effects of vasopressin on active and passive avoidance behavior

    NARCIS (Netherlands)

    Bohus, B.; Ader, R.; Wied, D. de

    1972-01-01

    Male rats were trained in an active avoidance and/or a “step-through” type of passive avoidance situation. Lysine vasopressin administration resulted in resistance to extinction of active avoidance behavior if it was injected 1 hr prior to the third and final acquisition session; peptide treatment 6

  8. Human keratinocytes are vanilloid resistant.

    Directory of Open Access Journals (Sweden)

    László Pecze

    Full Text Available BACKGROUND: Use of capsaicin or resiniferatoxin (RTX as analgesics is an attractive therapeutic option. RTX opens the cation channel inflammatory pain/vanilloid receptor type 1 (TRPV1 permanently and selectively removes nociceptive neurons by Ca(2+-cytotoxicity. Paradoxically, not only nociceptors, but non-neuronal cells, including keratinocytes express full length TRPV1 mRNA, while patient dogs and experimental animals that underwent topical treatment or anatomically targeted molecular surgery have shown neither obvious behavioral, nor pathological side effects. METHODS: To address this paradox, we assessed the vanilloid sensitivity of the HaCaT human keratinocyte cell line and primary keratinocytes from skin biopsies. RESULTS: Although both cell types express TRPV1 mRNA, neither responded to vanilloids with Ca(2+-cytotoxicity. Only ectopic overproduction of TRPV1 rendered HaCaT cells sensitive to low doses (1-50 nM of vanilloids. The TRPV1-mediated and non-receptor specific Ca(2+-cytotoxicity ([RTX]>15 microM could clearly be distinguished, thus keratinocytes were indeed resistant to vanilloid-induced, TRPV1-mediated Ca(2+-entry. Having a wider therapeutic window than capsaicin, RTX was effective in subnanomolar range, but even micromolar concentrations could not kill human keratinocytes. Keratinocytes showed orders of magnitudes lower TRPV1 mRNA level than sensory ganglions, the bona fide therapeutic targets in human pain management. In addition to TRPV1, TRPV1b, a dominant negative splice variant was also noted in keratinocytes. CONCLUSION: TRPV1B expression, together with low TRPV1 expression, may explain the vanilloid paradox: even genuinely TRPV1 mRNA positive cells can be spared with therapeutic (up to micromolar doses of RTX. This additional safety information might be useful for planning future human clinical trials.

  9. Corrosion-resistant uranium

    Science.gov (United States)

    Hovis, V.M. Jr.; Pullen, W.C.; Kollie, T.G.; Bell, R.T.

    1981-10-21

    The present invention is directed to the protecting of uranium and uranium alloy articles from corrosion by providing the surfaces of the articles with a layer of an ion-plated metal selected from aluminum and zinc to a thickness of at least 60 microinches and then converting at least the outer surface of the ion-plated layer of aluminum or zinc to aluminum chromate or zinc chromate. This conversion of the aluminum or zinc to the chromate form considerably enhances the corrosion resistance of the ion plating so as to effectively protect the coated article from corrosion.

  10. Measuring The Contact Resistances Of Photovoltaic Cells

    Science.gov (United States)

    Burger, D. R.

    1985-01-01

    Simple method devised to measure contact resistances of photovoltaic solar cells. Method uses readily available equipment and applicable at any time during life of cell. Enables evaluation of cell contact resistance, contact-end resistance, contact resistivity, sheet resistivity, and sheet resistivity under contact.

  11. Ceftobiprole- and ceftaroline-resistant methicillin-resistant Staphylococcus aureus.

    Science.gov (United States)

    Chan, Liana C; Basuino, Li; Diep, Binh; Hamilton, Stephanie; Chatterjee, Som S; Chambers, Henry F

    2015-05-01

    The role of mecA mutations in conferring resistance to ceftobiprole and ceftaroline, cephalosporins with anti-methicillin-resistant Staphylococcus aureus (MRSA) activity, was determined with MRSA strains COL and SF8300. The SF8300 ceftaroline-passaged mutant carried a single mecA mutation, E447K (E-to-K change at position 447), and expressed low-level resistance. This mutation in COL conferred high-level resistance to ceftobiprole but only low-level resistance to ceftaroline. The COL ceftaroline-passaged mutant, which expressed high-level resistance to ceftobiprole and ceftaroline, had mutations in pbp2, pbp4, and gdpP but not mecA.

  12. On Resisting Social Influence

    Science.gov (United States)

    1979-09-01

    sickness, no death. The discontinuities were there to be perceived. "The moment I got off that plane I knew somethin’ was wrong," said Richard Clark...indebted and g’iity. Diane Loule, who escaped Jonestown with Richard Clark the morning of the massacre, recounted for us her experience in the hospital...Times, November 27, 1978, p.28ff. Bandler , R., & Grinder, J. The structure of magic. 2 vols. Palo Alto, Calif.: Science and Behavior Books, 1975

  13. Irradiation Behavior in High Entropy Alloys

    Institute of Scientific and Technical Information of China (English)

    Song-qin XIA; Zhen WANG; Teng-fei YANG; Yong ZHANG

    2015-01-01

    As an increasing demand of advanced nuclear fission reactors and fusion facilities, the key requirements for the materials used in advanced nuclear systems should encompass superior high temperature property, good behavior in corrosive environment, and high irradiation resistance, etc. Recently, it was found that some selected high entropy alloys (HEAs) possess excellent mechanical properties at high temperature, high corrosion resistance, and no grain coarsening and self-healing abil-ity under irradiation, especially, the exceptional structural stability and lower irradiation-induced volume swelling, compared with other conventional materials. Thus, HEAs have been considered as the potential nuclear materials used for future ifssion or fusion reactors, which are designed to operate at higher temperatures and higher radiation doses up to several hundreds of displacement per atom (dpa). An insight into the irradiation behavior of HEAs was given, including fundamental researches to investigate the irradiation-induced phase crystal structure change and volume swelling in HEAs. In summary, a brief overview of the irradiation behavior in HEAs was made and the irradiation-induced structural change in HEAs may be relatively insensi-tive because of their special structures.

  14. Motivation of fitness center participants toward resistance training.

    Science.gov (United States)

    Kathrins, Bess P; Turbow, David J

    2010-09-01

    There is a need to better understand the behavior and sense of motivation of fitness center participants. The purpose of this study was to assess whether or not demographic characteristics and health self-determinism (intrinsic or extrinsic motivation) of fitness center participants were predictive of their levels of resistance training. A cross-sectional design was used; participants were recruited via the Internet to complete an online survey. There were 185 participants (age = 39.1 +/- 11.3 years) in the study. The majority of respondents reported having carried out levels of resistance training that met national health organization recommendations. Regression analysis of the data revealed that health self-determinism predicted quantity of resistance training reported (p = 0.014), whereas demographics did not. Being intrinsically motivated to health self-determinism predicted meeting national resistance training recommendations compared to participants extrinsically motivated (p = 0.007). For those who work with fitness center participants, our findings are useful by identifying participants as a predominantly intrinsically motivated group of people that performs adequate quantities of resistance training; the methodology employed in this study can be used to identify participants in need of increased levels of resistance training and heightened sense of motivation to do so.

  15. A resistência olha a resistência

    Directory of Open Access Journals (Sweden)

    Jorge Ponciano Ribeiro

    Full Text Available Resistência é um processo humano que acontece quando a pessoa se encontra sob algum tipo de ameaça. Não é essencialmente um acontecimento psicoterapêutico. Ocorre na terapia não como uma oposição a si mesmo ou ao terapeuta, mas como uma forma de se ajustar a uma nova situação. A resistência, é por natureza, a atualização do instinto de auto-preservação. E o organismo inteligentemente segue a lei da preferência. Resistência é uma forma de contato que não pode ser destruída, mas administrada, porque ela surge como uma defesa da totalidade vivenciada pela pessoa. A Resistência é, às vezes, resistência e awareness mais que ao contato. Ela revela mais o caminho seguido do que oculta a caminhada feita. A resistência é um processo natural, porque o corpo que não resiste, morre, mas falamos em processos de auto-regulação organísmica. Valorizamos mais o que mantêm a resistência funcionando do que à própria resistência. O terapeuta também resiste, ou seja, ele se auto-regula na sua relação com o cliente. Não questionamos a resistência, mas o processo que a mantêm. Trabalhamos com nove mecanismos de defesa, também tradicionalmente, chamados de resistência.

  16. First resistance mechanisms characterization in glyphosate-resistant Leptochloa virgata.

    Directory of Open Access Journals (Sweden)

    Ricardo Alcántara-de la Cruz

    2016-11-01

    Full Text Available Leptochloa virgata (L. P. Beauv. is an annual weed common in citrus groves in the states of Puebla and Veracruz, Mexico limiting their production. Since 2010, several L. virgata populations were identified as being resistant to glyphosate, but studies of their resistance mechanisms developed by this species have been conducted. In this work, three glyphosate-resistant populations (R8, R14 and R15 collected in citrus orchards from Mexico, were used to study their resistance mechanisms comparing them to one susceptible population (S. Dose-response and shikimic acid accumulation assays confirmed the glyphosate resistance of the three resistant populations. Higher doses of up to 720 g ae ha-1 (field dose were needed to control by 50% plants of resistant populations. The S population absorbed between 7 and 13% more 14C-glyphosate than resistant ones, and translocated up to 32.2% of 14C-glyphosate to the roots at 96 h after treatment (HAT. The R8, R14 and R15 populations translocated only 24.5, 26.5 and 21.9%, respectively. The enzyme activity of 5-enolpyruvyl shikimate-3-phosphate synthase (EPSPS was not different in the S, R8 and R14 populations. The R15 Population exhibited 165.9 times greater EPSPS activity. Additionally, this population showed a higher EPSPS basal activity and a substitution in the codon 106 from Proline to Serine in the EPSPS protein sequence. EPSPS gene expression in the R15 population was similar to that of S population. In conclusion, the three resistant L. virgata populations show reduced absorption and translocation of 14C-glyphosate. Moreover, a mutation and an enhanced EPSPS basal activity at target-site level confers higher resistance to glyphosate. These results describe for the first time the glyphosate resistance mechanisms developed by resistant L. virgata populations of citrus orchards from Mexico.

  17. First Resistance Mechanisms Characterization in Glyphosate-Resistant Leptochloa virgata

    Science.gov (United States)

    Alcántara-de la Cruz, Ricardo; Rojano-Delgado, Antonia M.; Giménez, María J.; Cruz-Hipolito, Hugo E.; Domínguez-Valenzuela, José A.; Barro, Francisco; De Prado, Rafael

    2016-01-01

    Leptochloa virgata (L.) P. Beauv. is an annual weed common in citrus groves in the states of Puebla and Veracruz, Mexico limiting their production. Since 2010, several L. virgata populations were identified as being resistant to glyphosate, but studies of their resistance mechanisms developed by this species have been conducted. In this work, three glyphosate-resistant populations (R8, R14, and R15) collected in citrus orchards from Mexico, were used to study their resistance mechanisms comparing them to one susceptible population (S). Dose-response and shikimic acid accumulation assays confirmed the glyphosate resistance of the three resistant populations. Higher doses of up to 720 g ae ha-1 (field dose) were needed to control by 50% plants of resistant populations. The S population absorbed between 7 and 13% more 14C-glyphosate than resistant ones, and translocated up to 32.2% of 14C-glyphosate to the roots at 96 h after treatment (HAT). The R8, R14, and R15 populations translocated only 24.5, 26.5, and 21.9%, respectively. The enzyme activity of 5-enolpyruvyl shikimate-3-phosphate synthase (EPSPS) was not different in the S, R8 and R14 populations. The R15 Population exhibited 165.9 times greater EPSPS activity. Additionally, this population showed a higher EPSPS basal activity and a substitution in the codon 106 from Proline to Serine in the EPSPS protein sequence. EPSPS gene expression in the R15 population was similar to that of S population. In conclusion, the three resistant L. virgata populations show reduced absorption and translocation of 14C-glyphosate. Moreover, a mutation and an enhanced EPSPS basal activity at target-site level confers higher resistance to glyphosate. These results describe for the first time the glyphosate resistance mechanisms developed by resistant L. virgata populations of citrus orchards from Mexico. PMID:27917189

  18. Critical behavior of resistivity in the pressure-induced first to second order transition in Pr{sub 0.6}Ca{sub 0.4}Mn{sub 0.96}B{sub 0.04}O{sub 3} (B=Co and Cr) polycrystals

    Energy Technology Data Exchange (ETDEWEB)

    Thiyagarajan, R.; Arumugam, S., E-mail: sarumugam1963@yahoo.com [Centre for High Pressure Research, School of Physics, Bharathidasan University, Tiruchirapalli-620024, Tamil Nadu (India); Mahendiran, R. [Department of Physics, 2 Science Drive 3, Faculty of Science, National University of Singapore, Singapore-117551 (Singapore)

    2015-06-24

    We have investigated the hydrostatic pressure (P) dependence of the resistivity on Pr{sub 0.6}Ca{sub 0.4}Mn{sub 0.96}B{sub 0.04}O{sub 3} (B = Co and Cr) polycrystals. At ambient pressure, the temperature dependence of resistivity [ρ(T)] of both the samples show a first order paramagnetic insulator-ferromagnetic metallic transition at T=T{sub IM}. The application of P on both the samples increases the T{sub IM}, reduces the resistivity, and suppresses the hysteresis width, indicating a crossover from first to second order transition. The critical pressure, where the first-second order crossover takes place, are 2.02 and 2.40 GPa for Co and Cr doped samples respectively. The critical property of both systems around second order transition is investigated using Fisher-Langer relation and Suezaki-Mori method. The estimated critical exponents are close to the three-dimensional Heisenberg model for the Co doped sample suggesting short range interaction, and the exponents for the Cr doped sample follow the mean field theory suggesting long range ferromagnetic order. Further, the application of P suppresses the high temperature resistivity by reducing high temperature polarons in the case of the Cr doped sample, but it does not happen for the Co doped sample. The application of P helps to examine the stability of polarons in the high temperature regime.

  19. Personality and Prosocial Behavior

    DEFF Research Database (Denmark)

    Hilbig, Benjamin E; Glöckner, Andreas; Zettler, Ingo

    2014-01-01

    Concerning the dispositional determinants of prosocial behavior and cooperation, work based on the classic 5 personality factors, and especially Agreeableness, has turned out somewhat inconsistent. A clearer picture has emerged from consideration of the HEXACO model of personality-though supported...... entirely by hypothetical behavior as criterion, so far. Thus, in 2 studies and a reanalysis, we investigated "actual behavior" in the form of individually and socially consequential distribution decisions. As expected, HEXACO Honesty-Humility consistently predicted prosocial behavior, including a theory......-consistent pattern on the facet level. Importantly, this pattern might explain why five-factor Agreeableness has only sometimes been found to account for prosocial behavior. Indeed, further results indicate that five-factor Agreeableness comprises some aspects that are predictive of prosocial behavior-aspects well...

  20. [Addictive behavior disorders].

    Science.gov (United States)

    Masaki, Daiki; Tsuchida, Hideto; Kitabayashi, Yurinosuke; Tani, Naosuke; Fukui, Kenji

    2007-10-01

    "Addiction" used to remind anyone of the use or abuse of chemical substances. In recent years, however, researchers and clinicians have begun to classify other excessive behaviors including gambling, eating shopping and self-injury into the addictive behavior. Above all, pathological gambling and bulimia nervosa patients often make trouble for psychiatrists and psychologists, not only for their family. On the other hand, the neural substrata underlying substance dependence have been revealed. Especially, it is implicated that the mesolimbic neuron plays a crucial role on the reward system. The recent studies suggest that reduced activation of the reward system might be related to the addictive behaviors such as pathological gambling, binge eating and sexual behavior. Further biological researches about the addictive behavior would help our deeper understanding of its disorders. As to the pharmacotherapy, many studies have demonstrated the efficacy of selective serotonin reuptake inhibitors (SSRIs) in treating the addictive behaviors.

  1. Magnetic hysteresis of the zero-resistance critical temperature of high-T{sub c} granular superconductors

    Energy Technology Data Exchange (ETDEWEB)

    Flores, L.; Altshuler, E.; Garcia, S. [Univ. of Havana (Cuba)] [and others

    1995-10-01

    The authors have found a notorious hysteretic behavior in the dependence of the zero-resistance critical temperature obtained through resistivity ({rho}) versus temperature (T) measurements with applied field (H{sub c}) in High-T{sub c} granular superconductors. This behavior is explained semi-quantitatively based on the analogy between the present observation and a similar hysteresis found in the field dependence of the transport critical current in these materials.

  2. [Neruda and antimicrobial resistance].

    Science.gov (United States)

    Cotera, Alejandro

    2011-07-01

    Antimicrobial resistance has been a problem in medicine, since their incorporation to clinical practice. Numerous papers have been written on the subject. The analysis of two poems by Pablo Neruda "How much does a man live" and "Larynx", included in the volume "Estravagario" and published for the first time in 1957 and 1958, give us an incredible revelation about the concept of resistance. In these poems aureomycin, the first antimicrobial of the family of tetracyclines, was included as a poetic figure and the therapeutic action of antimicrobials was described. "Never so much bugs died I tons of them fell I but the few that remained olive I manifested their perversity". These writings incorporated novel concepts, even for physicians of that time and described the closeness of death that a patient may perceive during the course of a given disease. The capacity of Pablo Neruda to extract the essence of situations and to anticipate to conditions that only years later became clinically relevant problems, is noteworthy.

  3. Novel resists for nanolithography

    CERN Document Server

    Robinson, A P G

    1999-01-01

    10 sup - sup 2 C/cm sup 2. The polysubstituted triphenylene derivatives demonstrated negative tone sensitivities in the range approx 1.5 x 10 sup - sup 3 to approx 6.5 x 10 sup - sup 3 C/cm sup 2 , again increasing in an approximately linear manner with molecular mass. The derivative hexapentyloxytriphenylene behaved as a positive tone resist for electron doses between approx 3 x 10 sup - sup 4 and approx 2.5 x 10 sup - sup 3 C/cm sup 2 with developers such as 2-pentanol. The negative tone resolution of the compounds was found to be at least as good as 20 nm in most cases and approx 14 nm in the case of hexa-pentyloxytriphenylene. The etch durabilities of these compounds, for dry plasma etching with SF sub 6 , are very high -- at least double that of a conventional high durability novolac resist for the methanofullerenes and approximately double the novolac durability for the polysubstituted triphenylene derivatives. This thesis describes the experimental study of two new families of low molecular mass electr...

  4. Oxidation Resistant Graphite Studies

    Energy Technology Data Exchange (ETDEWEB)

    W. Windes; R. Smith

    2014-07-01

    The Very High Temperature Reactor (VHTR) Graphite Research and Development Program is investigating doped nuclear graphite grades exhibiting oxidation resistance. During a oxygen ingress accident the oxidation rates of the high temperature graphite core region would be extremely high resulting in significant structural damage to the core. Reducing the oxidation rate of the graphite core material would reduce the structural effects and keep the core integrity intact during any air-ingress accident. Oxidation testing of graphite doped with oxidation resistant material is being conducted to determine the extent of oxidation rate reduction. Nuclear grade graphite doped with varying levels of Boron-Carbide (B4C) was oxidized in air at nominal 740°C at 10/90% (air/He) and 100% air. The oxidation rates of the boronated and unboronated graphite grade were compared. With increasing boron-carbide content (up to 6 vol%) the oxidation rate was observed to have a 20 fold reduction from unboronated graphite. Visual inspection and uniformity of oxidation across the surface of the specimens were conducted. Future work to determine the remaining mechanical strength as well as graphite grades with SiC doped material are discussed.

  5. CMS Resistive plate Champers

    CERN Document Server

    Zainab, Karam

    2013-01-01

    There are many types of gas detectors which are used in CERN in LHC project, There is a main parts for the gas detectors which must be in all gas detectors types like Multiwire proportional chambers, such as the micromesh gaseous structure chamber (the MicroMegas), Gas-electron multiplier (GEM) detector, Resistive Plate Champers... Compact Muon Solenoid (CMS) experiment detecting muons which are powerful tool for recognizing signatures of interesting physics processes. The CMS detector uses: drift tube (DT), cathode strip chamber (CSC) and resistive plate chamber (RPC). Building RPC’s was my project in summer student program (hardware). RPC’s have advantages which are triggering detector and Excellent time resolution which reinforce the measurement of the correct beam crossing time. RPC’s Organized in stations :  RPC barrel (RB) there are 4 stations, namely RB1, RB2, RB3, and RB4  While in the RPC endcap (RE) the 3 stations are RE1, RE2, and RE3. In the endcaps a new starion will be added and this...

  6. Antimicrobial resistance in bacteria from horses: Epidemiology of antimicrobial resistance.

    Science.gov (United States)

    Maddox, T W; Clegg, P D; Williams, N J; Pinchbeck, G L

    2015-11-01

    Antimicrobial resistance poses a significant threat to the continued successful use of antimicrobial agents for the treatment of bacterial infections. While the epidemiology of antimicrobial resistance in bacteria from man has been studied extensively, less work has been undertaken in companion animals, particularly horses. Methicillin-resistant Staphylococcus aureus has been identified as a cause of infections, with a low prevalence of nasal carriage by horses in the community but higher for hospitalised horses. Molecular characterisation has shown methicillin-resistant Staphylococcus aureus strains either to be predominantly of types associated with horses or of sequence type ST398. Antimicrobial-resistant Escherichia coli (including multidrug-resistant and extended spectrum β-lactamase-producing isolates) have caused infections and been documented in faecal carriage by horses, with many significant resistance mechanisms identified. More sporadic reports and molecular characterisation exist for resistance in other bacteria such as enterococci, Salmonella, Acinetobacter and Pseudomonas species. Limited work has been undertaken evaluating risk factors and much of the epidemiology of antimicrobial resistance in bacteria from horses remains to be determined.

  7. About Teleological Behaviorism.

    Science.gov (United States)

    Rachlin, Howard

    2013-01-01

    Misconceptions abound about teleological behaviorism (TB). Because very few people other than the author publicly call themselves teleological behaviorists, the fault must be mine. The present article is an attempt to clear up those misconceptions. First I will try to indicate what teleological behaviorism is not. Then, in the form of six fables (loosely connected stories, allegories, analogies, fairy tales, and arguments), I will try to give the reader an understanding of what teleological behaviorism actually is.

  8. Correlation between tension softening relation and crack extension resistance in concrete

    Institute of Scientific and Technical Information of China (English)

    Xiufang ZHANG; Shilang XU

    2009-01-01

    Changes of the material fracture toughness with crack propagation can be described by a crack extension resistance curve, one of the fundamental fracture criteria in crack mechanics. Recently, experimental observation of the fracture behavior in concrete was used to develop a new fracture criterion, the crack extension GR resistance curve, to analyze crack propagation during the entire concrete fracture process. The variation of the crack extension resistance is mainly associated with the energy consumption in the fracture process zone ahead of the stress-free crack tip. The crack extension resistance is then a function of the softening curve, which is a basic mechanical property in the fracture process zone. The relationship between the softening curve and the crack extension GR resistance curve is then analyzed based on results of three-point bending beams tests. The results indicate that the characteristic points of the crack extension resistance GR curve is closely related to the characteristic point on used tension softening curve.

  9. Self-assembled tin dioxide for forming-free resistive random-access memory application

    Science.gov (United States)

    Hong, Ying-Jhan; Wang, Tsang-Hsuan; Wei, Shih-Yuan; Chang, Pin; Yew, Tri-Rung

    2016-06-01

    A novel resistive switching structure, tin-doped indium oxide (ITO)/SnO2- x (defined as SnO2 with oxygen vacancies)/SnS was demonstrated with a set voltage of 0.38 V, a reset voltage of -0.15 V, a ratio of high resistance to low resistance of 544, and forming-free and nonlinear current-voltage (I-V) characteristics. The interface of the ITO and the self-assembled SnO2- x contributed to the resistive switching behavior. This device showed great potential for resistive random access memory (RRAM) application and solving the sneak path problem in cross-bar memory arrays. Furthermore, a nanostructured resistive switching device was demonstrated successfully.

  10. Enhancement of Corrosion Resistance of Zinc Coatings Using Green Additives

    Science.gov (United States)

    Punith Kumar, M. K.; Srivastava, Chandan

    2014-10-01

    In the present work, morphology, microstructure, and electrochemical behavior of Zn coatings containing non-toxic additives have been investigated. Zn coatings were electrodeposited over mild steel substrates using Zn sulphate baths containing four different organic additives: sodium gluconate, dextrose, dextrin, and saccharin. All these additives are "green" and can be derived from food contents. Morphological and structural characterization using electron microscopy, x-ray diffraction, and texture co-efficient analysis revealed an appreciable alteration in the morphology and texture of the deposit depending on the type of additive used in the Zn plating bath. All the Zn coatings, however, were nano-crystalline irrespective of the type of additive used. Polarization and electrochemical impedance spectroscopic analysis, used to investigate the effect of the change in microstructure and morphology on corrosion resistance behavior, illustrated an improved corrosion resistance for Zn deposits obtained from plating bath containing additives as compared to the pure Zn coatings.

  11. Behavioral Public Administration

    DEFF Research Database (Denmark)

    Grimmelikhuijsen, Stephan; Jilke, Sebastian; Olsen, Asmus Leth

    2017-01-01

    Behavioral public administration is the analysis of public administration from the micro-level perspective of individual behavior and attitudes by drawing on insights from psychology on the behavior of individuals and groups. The authors discuss how scholars in public administration currently draw...... theories. As such, behavioral public administration complements traditional public administration. Furthermore, it could be a two-way street for psychologists who want to test the external validity of their theories in a political-administrative setting. Finally, four principles are proposed to narrow...

  12. Green Consumption Behavior Antecedents

    DEFF Research Database (Denmark)

    Pagiaslis, Anastasios; Krystallis Krontalis, Athanasios

    2014-01-01

    The present study adds to the evolving literature on green consumer behavior by examining through statistically robust methods the effect and interrelationships of the key constructs of environmental concern, consumer environmental knowledge, beliefs about biofuels, and behavioral intention (i...... for the environment has a positive and direct impact on environmental knowledge, beliefs, and behavioral intention. Also, demographics determine levels of concern for the environment and environmental knowledge. All constructs associate positively with one another delineating that the interdependencies between them...... are important when accounting for environmental behavior. Future research should validate present results with the use of cross-cultural samples and investigate whether environmental concern increases due to social desirability response bias....

  13. Behavioral Neuroscience Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — This lab supports cognitive research using rodent models. Capabilities for behavioral assessments include: Morris water maze and Barnes maze (spatial memory) elevate...

  14. Male rat sexual behavior.

    Science.gov (United States)

    Agmo, A

    1997-05-01

    The male rat's sexual behavior constitutes a highly ordered sequence of motor acts involving both striate and smooth muscles. It is spontaneously displayed by most adult made rats in the presence of a sexually receptive female. Although the behavior is important for the survival of the species it is not necessary for survival of the individual. In that way it is different from other spontaneous behaviors such as eating, drinking, avoidance of pain, respiration or thermoregulation. Among other things, this means that it is difficult to talk about sexual deprivation or need. Nevertheless, studies of male sex behavior distinguish sexual motivation (the ease by which behavior is activated, "libido") from the execution of copulatory acts (performance, "potency") (Meisel, R.L. and Sachs, B.D., The physiology of male sexual behavior. In: E. Knobil and J.D. Neill (Eds.), The Physiology of Reproduction, 2nd Edn., Vol. 2, Raven Press, New York, 1994, pp. 3-105 [13]). The hormonal control of male sexual behavior has been extensively studied. It is clear that steroid hormones, androgens and estrogens, act within the central nervous system, modifying neuronal excitability. The exact mechanism by which these hormones activate sex behavior remains largely unknown. However, there exists a considerable amount of knowledge concerning the brain structures important for sexual motivation and for the execution of sex behavior. The modulatory role of some non-steroid hormones is partly known, as well as the consequences of manipulations of several neurotransmitter systems.

  15. POST BEHAVIORAL FINANCE ADOLESCENCE

    Directory of Open Access Journals (Sweden)

    ADRIAN MITROI

    2016-12-01

    Full Text Available The study of behavioral finance combines the investigation and expertise from research and practice into smart portfolios of individual investors’ portfolios. Understanding cognitive errors and misleading emotions drive investors to their long-term goals of financial prosperity and capital preservation. 10 years ago, Behavioral Finance was still considered an incipient, adolescent science. First Nobel Prize in Economics awarded to the study of Behavioral Economics in 2002 established the field as a new, respected study of economics. 2013 Nobel Prize was awarded to three economists, one of them considered the one of the founders of the Behavioral Finance. As such, by now we are entering the coming of age of behavioral finance. It is now recognized as a science of understanding investors behaviors and their biased patterns. It applies quantitative finance and provides practical models grounded on robust understanding of investors behavior toward financial risk. Financial Personality influences investment decisions. Behavioral portfolio construction methods combine classic finance with rigorously quantified psychological metrics and improves models for financial advice to enhance investors chances in reaching their lifetime financial goals. Behavioral finance helps understanding psychological profile dissimilarities of individuals and how these differences manifest in investment decision process. This new science has become now a must topic in modern finance.

  16. Behavioral Neuroscience Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — This lab supports cognitive research using rodent models. Capabilities for behavioral assessments include:Morris water maze and Barnes maze (spatial memory)elevate...

  17. How to fight antimicrobial resistance.

    Science.gov (United States)

    Foucault, Cédric; Brouqui, Philippe

    2007-03-01

    Antimicrobial misuse results in the development of resistance and superbugs. Over recent decades, resistance has been increasing despite continuing efforts to control it, resulting in increased mortality and cost. Many authorities have proposed local, regional and national guidelines to fight against this phenomenon, and the usefulness of these programmes has been evaluated. Multifaceted intervention seems to be the most efficient method to control antimicrobial resistance. Monitoring of bacterial resistance and antibiotic use is essential, and the methodology has now been homogenized. The implementation of guidelines and infection control measures does not control antimicrobial resistance and needs to be reinforced by associated measures. Educational programmes and rotation policies have not been evaluated sufficiently in the literature. Combination antimicrobial therapy is inefficient in controlling antimicrobial resistance.

  18. New creep resistant cast alloys with improved oxidation resistance in water vapor at 650-800ºC

    OpenAIRE

    Sebastien eDryepondt; Pint, Bruce A.; Maziasz, Philip J.

    2015-01-01

    Cast stainless steel CF8C-Plus (19wt.%Cr/12%Ni) has excellent creep properties, but limited oxidation resistance above 700ºC in environments containing H2O. One strategy to improve the alloy oxidation performance is to increase the Cr and Ni concentration. Two new alloys, with respectively 21wt%Cr-15wt%Ni and 22wt%Cr-17.5wt%Ni were therefore developed and their long-term oxidation behavior in humid air were compared with the oxidation behavior of five other cast alloys. At 650 and 700ºC, all ...

  19. New Creep-Resistant Cast Alloys with Improved Oxidation Resistance in Water Vapor at 650–800°C

    OpenAIRE

    Dryepondt, Sebastien; Pint, Bruce A.; Maziasz, Philip J.

    2015-01-01

    Cast stainless steel CF8C-Plus (19wt%Cr/12%Ni) has excellent creep properties, but limited oxidation resistance above 700°C in environments containing H2O. One strategy to improve the alloy oxidation performance is to increase the Cr and Ni concentration. Two new alloys, with, respectively, 21wt%Cr–15wt%Ni and 22wt%Cr–17.5wt%Ni were therefore developed and their long-term oxidation behaviors in humid air were compared with the oxidation behavior of five other cast alloys. At 650°C and 700°C, ...

  20. Differential gene expression associated with honey bee grooming behavior in response to varroa mites

    Science.gov (United States)

    Honey bee (Apis mellifera) grooming behavior is an important mechanism of resistance against the parasitic mite Varroa destructor. This research was conducted to study associations between grooming behavior and the expression of selected immune, neural, detoxification, developmental and health-relat...