Self-reinforcement Behavior Research Articles

A novel dual-network CO2-responsive particle gel for mitigating CO2 channeling and leakage in hydrocarbon recovery and carbon storage

In this work, we developed and systematically evaluated a novel dual-network CO2-responsive preformed particle gel (DN-CRPPG) to address CO2 channeling and leakage in hydrocarbon recovery and carbon sequestration. The work was proven an effective effort to overcome the insufficiency of traditional channeling-control chemicals due to severe dehydration and degradation in contact with CO2. We focused on placement and plugging behavior of the DN-CRPPG in fractured reservoirs under various circumstances. Results of high-pressure vessel test show that DN-CRPPG expanded further when exposed to supercritical CO2. The responsive swelling ability was enhanced with the increase of pressure. Core flooding and plugging experiments show significantly improved CO2-channeling control ability compared with traditional non-responsive particle gels. Three key mechanisms were observed to be responsible for the improved performance. First, the CO2-responsive behavior resulted in volume swelling of DN-CRPPG. Therefore, the void spaces among the particles were occupied by the swelled gel particles, making the DN-CRPPG exhibit an in-situ self-reinforcement behavior in plugging ability. Second, the dual network structure with a relatively rigid network and a more flexible one enhances its mechanical ability and resistance to CO2 flush. Third, the CO2-repsonsiveness enabled the new gel a remarkably higher resistance to CO2 than that to water, while traditional gel is the opposite. This behavior is favorable for balancing the mobility of CO2 and water as the fact that CO2 itself is much more mobile due to low viscosities. Significant CO2 breakthrough mitigation and oil recovery improvement were demonstrated after treatment with the new gel (>30 %). This work is supposed to provide guidance for improving the success of hydrocarbon recovery and carbon storage by more effectively mitigating CO2 channeling and leakage.

Natural Phytic Acid-Assisted Polyaniline/Poly(vinyl alcohol) Hydrogel Showing Self-Reinforcing Features.

Polyaniline (PANi) hydrogels that combine advantages of hydrogels and conductive PANi have recently emerged in areas of wearable devices and personal healthcare. Nevertheless, their mechanical performance often gradually degrades after being used for a period, caused by destruction of the inner structures when external forces are applied. Inspired by biological structures with persistent durability, we develop here a phytic acid-assisted PANi/poly(vinyl alcohol) (PVA) hydrogel that shows self-reinforcing features. As a natural product holding plenty of phosphate groups, phytic acid (PA) plays two crucial roles when preparing this hydrogel: (1) aniline is salinized by PA in aqueous solution to promote in situ polymerization, making the resulting PANi conductive; (2) PA/PANi particles form hydrogen bonds with PVA, acting as stress concentration points to induce structure orientation. The optimal PVA/PA/PANi hydrogel displays dark green color with a uniform distribution of PA/PANi particles. After experiencing repetitive 4 × 100 stretching at a strain of 10%, the hydrogel exhibits an enhanced fracture strength (20.35 MPa), Young's modulus (22.66 MPa), and toughness (36.24 MJ·m-3) compared with the original hydrogel. This self-reinforcing feature is mainly attributed to the formation of anisotropic structures fixed by hydrogen bonds between PA/PANi particles and PVA chains upon repetitive external forces. Moreover, anisotropic structures can be disassembled by swelling the post-stretched hydrogel in water, and the swollen hydrogel shows similar self-reinforcing behaviors. The good mechanical durability and reusable characteristics make the PVA/PA/PANi hydrogel a reliable strain sensor. This work provides a structural growing-reviving approach for conductive hydrogels with persistent durability.

Surface restructuring in AgCu single-atom alloy catalyst and self-enhanced selectivity toward CO2 reduction

Single atom alloy catalysts, consisting of trace amount of isolated solute atoms alloyed into the host matrix, provide a promising approach to tune the electronic structure and performance of bimetallic catalysts for breaking the limits of scaling relationships based on the unique electronic structures. However, the precisely as-synthesized surface usually suffers from surface evolution leading to activity and durability decay. Herein, the understanding of surface restructuring under reaction conditions is of great importance in optimizing catalytic performance of bimetallic catalysts. In this work, on account of the surface evolution of Cu in electrochemical reactions and its limited miscibility in Ag, a nanoporous AgCu single atom alloy catalyst with atomic ratio Cu:Ag = 1:110 is fabricated by chemical dealloying process. And a CO2-reduction-induced surface restructuring is achieved upon the well-designed catalyst. Noteworthily, nanoporous AgCu exhibits self-reinforcing selectivity toward CO2 reduction and suppressed hydrogen evolution in parallel with migration of Cu to the surface, although the charge transfer from Ag to Cu results in a strong tendency toward hydrogen evolution at the initial catalytic stage. By combining in situ electrochemical hypersensitive response to surface state with ex situ characterizations, the surface reconstruction is verified to be driven by electrochemical reduction of CO2 rather than hydrogen evolution reaction, and can be modulated by the applied potential. Well-reconstructed nanoporous AgCu facilitates the adsorption of CO2. Electronic effect of the restructuring of Cu enhances CO desorption ability on the surface. Consequently, electronic and geometric effects synergically lead to excellent performances with CO Faradaic efficiency of 97.5%. The insights gained from the reconstruction-induced self-reinforcing behavior of bimetallic electrocatalyst shall offer an avenue to rationally design bimetallic electrocatalysts for electrochemical CO2 reduction.

Realizing self-reinforcement of polyethylene via high-speed shear processing

As one of the most representative polyolefins, polyethylene (PE) constitutes the largest consumption of thermoplastics in the world. Thus, the high-performance issue of PE, such as effective self-reinforcement, represents highly expected demand in both of academic and industrial areas. However, it induces a materials engineering challenge due to the difficulties in preparations of multiphase materials and technological complexities of processing. Here, we report a readily accessible self-reinforcement behavior of high-density polyethylene (HDPE) realized via using a commercially available technique, high-speed shear extrusion. A common grade of HDPE can be enhanced significantly for nearly 60%, depending on the rotation speed. The chromatography indicates that the molecular weight of HDPE is nearly constant after experiencing high-shearing effect. While a quasi-solid-like character is detected in the HDPE melt, which could be attributed to the increment of entanglement causing by severe mixing during extrusion. Subsequently, the enhanced entanglement enables the appearances of high orientation structure and specific crystalline morphology, which are responsible for the mechanical reinforcement observed. Our present study offers a promising avenue to access the manufacture of structural parts using polyolefin resins.

No Man is an Island: Social Coordination and the Environment

Humans are fundamentally social. Social activities require coordination, which may yield multiple equilibria in the form of stable, self-reinforcing patterns of herd behavior. Since environmental impacts can differ substantially between alternative equilibria, such self-reinforcing behaviors may, from an environmental perspective, be viewed as representing virtuous or vicious cycles. Environmental policies can help break the self-fulfilling expectations of vicious cycles, tipping the economy to more environment-friendly equilibria.

Surface effect on the self-reinforcing behavior of graphene oxide membranes

Cyclic microbridge tests were applied to investigate the mechanical properties of the 100-to-400-nm-thick graphene oxide membranes. The effective Young’s moduli of different thickness graphene oxide membranes were derived and proved to be size dependent. The self-reinforcing behavior of graphene oxide membranes, which exhibits as an increase in Young’s modulus after cyclic loading, was observed and turned out to be in a relationship with thickness. A theoretical analysis is presented to explain the size dependence of the self-reinforcing Young’s moduli. This work is meaningful for the applications of graphene oxide membranes and the development of basic elements of the micro/nano-electro-mechanical systems.

The Dorsal Medial Habenula Minimally Impacts Circadian Regulation of Locomotor Activity and Sleep.

In nocturnal rodents, voluntary wheel-running activity (WRA) represents a self-reinforcing behavior. We have previously demonstrated that WRA is markedly reduced in mice with a region-specific deletion of the transcription factor Pou4f1 (Brn3a), which leads to an ablation of the dorsal medial habenula (dMHb). The decrease in WRA in these dMHb-lesioned (dMHbCKO) mice suggests that the dMHb constitutes a critical center for conveying reinforcement by exercise. However, WRA also represents a prominent output of the circadian system, and the possibility remains that the dMHb is a source of input to the master circadian pacemaker located in the suprachiasmatic nucleus (SCN) of the hypothalamus. To test this hypothesis, we assessed the integrity of the circadian system in dMHbCKO mice. Here we show that the developmental lesion of the dMHb reduces WRA under both a light-dark cycle and constant darkness, increases the circadian period of WRA, but has no effect on the circadian amplitude or period of home cage activity or the daily amplitude of sleep stages, suggesting that the lengthening of period is a result of the decreased WRA in the mutant mice. Polysomnographic sleep recordings show that dMHbCKO mice have an overall unaltered daily amplitude of sleep stages but have fragmented sleep and an overall increase in total rapid eye movement (REM) sleep. Photoresponsiveness is intact in dMHbCKO mice, but compared with control animals, they reentrain faster to a 6-h abrupt phase delay protocol. Circadian changes in WRA of dMHbCKO mice do not appear to emerge within the central pacemaker, as circadian expression of the clock genes Per1 and Per2 within the SCN is normal. We do find some evidence for fragmented sleep and an overall increase in total REM sleep, supporting a model in which the dMHb is part of the neural circuitry encoding motivation and involved in the manifestation of some of the symptoms of depression.

A problem-solving routine for improving hospital operations

The purpose of this paper is to examine empirically why a systematic problem-solving routine can play an important role in the process improvement efforts of hospitals. Data on 18 process improvement cases were collected through semi-structured interviews, reports and other documents, and artifacts associated with the cases. The data were analyzed using a grounded theory approach. Adherence to all the steps of the problem-solving routine correlated to greater degrees of improvement across the sample. Analysis resulted in two models. The first partially explains why hospital workers tended to enact short-term solutions when faced with process-related problems; and tended not seek longer-term solutions that prevent problems from recurring. The second model highlights a set of self-reinforcing behaviors that are more likely to address problem recurrence and result in sustained process improvement. The study was conducted in one hospital setting. Hospital managers can improve patient care and increase operational efficiency by adopting and diffusing problem-solving routines that embody three key characteristics. This paper offers new insights on why caregivers adopt short-term approaches to problem solving. Three characteristics of an effective problem-solving routine in a healthcare setting are proposed.

Robust dual physically cross-linked hydrogels with unique self-reinforcing behavior and improved dye adsorption capacity

Schematic illumination of the self-reinforcement of DPC gels achieved by self-healing and remolding.

Where and Why Users "Check In"

The emergence of location based social network (LBSN) services makes it possible to study individuals’ mobility patterns at a fine-grained level and to see how they are impacted by social factors. In this study we analyze the check-in patterns in LBSN and observe significant temporal clustering of check-in activities. We explore how self-reinforcing behaviors, social factors, and exogenous effects contribute to this clustering and introduce a framework to distinguish these effects at the level of individual check-ins for both users and venues. Using check-in data from three major cities, we show not only that our model can improve prediction of future check-ins, but also that disentangling of different factors allows us to infer meaningful properties of different venues.

Playing Video Games While Using or Feeling the Effects of Substances: Associations with Substance Use Problems

This study tested the hypothesis that playing video games while using or feeling the effects of a substance—referred to herein as “concurrent use”—is related to substance use problems after controlling for substance use frequency, video gaming as an enthusiastic hobby, and demographic factors. Data were drawn from a nationally representative online survey of adult video gamers conducted by Knowledge Networks, valid n = 2,885. Problem video game playing behavior was operationalized using Tejeiro Salguero and Bersabé Morán’s 2002 problem video game play (PVP) measure, and measures for substance use problems were taken from the National Survey of Drug Use and Health (NSDUH). Separate structural equation modeling analyses were conducted for users of caffeine, tobacco, alcohol, and marijuana. In all four models, concurrent use was directly associated with substance use problems, but not with PVP. Video gaming as an enthusiastic hobby was associated with substance use problems via two indirect paths: through PVP for all substances, and through concurrent use for caffeine, tobacco, and alcohol only. Results illustrate the potential for “drug interaction” between self-reinforcing behaviors and addictive substances, with implications for the development of problem use.

Patterns of and Motivations for Concurrent Use of Video Games and Substances

“Behavioral addictions” share biological mechanisms with substance dependence, and “drug interactions” have been observed between certain substances and self-reinforcing behaviors. This study examines correlates of patterns of and motivations for playing video games while using or feeling the effects of a substance (concurrent use). Data were drawn from a nationally-representative survey of adult Americans who “regularly” or “occasionally” played video games and had played for at least one hour in the past seven days (n = 3,380). Only recent concurrent users’ data were included in analyses (n = 1,196). Independent variables included demographics, substance use frequency and problems, game genre of concurrent use (identified by looking titles up in an industry database), and general game playing variables including problem video game play (PVP), consumer involvement, enjoyment, duration, and frequency of play. Exploratory factor analysis identified the following dimensions underlying patterns of and motivations for concurrent use: pass time or regulate negative emotion, enhance an already enjoyable or positive experience, and use of video games and substances to remediate each other’s undesirable effects. Multivariate regression analyses indicated PVP and hours/day of video game play were associated with most patterns/motivations, as were caffeine, tobacco, alcohol, marijuana, and painkiller use problems. This suggests that concurrent use with some regular situational pattern or effect-seeking motivation is part of the addictive process underlying both PVP and substance dependence. Various demographic, game playing, game genre of concurrent use, and substance use variables were associated with specific motivations/patterns, indicating that all are important in understanding concurrent use.

Computational Design of Active, Self-Reinforcing Gels

Many living organisms have evolved a protective mechanism that allows them to reversibly alter their stiffness in response to mechanical contact. Using theoretical modeling, we design a mechanoresponsive polymer gel that exhibits a similar self-reinforcing behavior. We focus on cross-linked gels that contain Ru(terpy)(2) units, where both terpyridine ligands are grafted to the chains. The Ru(terpy)(2) complex forms additional, chemoresponsive cross-links that break and re-form in response to a repeated oxidation and reduction of the Ru. In our model, the periodic redox variations of the anchored metal ion are generated by the Belousov-Zhabotinsky (BZ) reaction. Our computer simulations reveal that compression of the BZ gel leads to a stiffening of the sample due to an increase in the cross-link density. These findings provide guidelines for designing biomimetic, active coatings that send out a signal when the system is impacted and use this signaling process to initiate the self-protecting behavior.

Culture and the intergenerational transmission of substance abuse, woman abuse, and child abuse: A diathesis-stress perspective

This manuscript focuses on culture as moderating the transmission of substance abuse and spouse abuse to impact child well-being in families across generations. Within the context of a diathesis-stress model, the authors propose that it is the interaction between particular internal factors, such as biochemical, genetic, and/or psychosocial factors, and external factors that is critical in understanding intergenerational transmission. Based on a review of related literature, the authors suggest a nonlinear dynamic perspective on intergenerational transmission that maintains a presumption of cultural and ethnic “environment” distinctly interacting with genetics and physiology to produce self-reinforcing behaviors that may be passed from one generation to another.

Self-reinforcement schedules in young children: effects of motivational orientation and instructional demands

The effects of external (environmental) and internal (cognitive) self regulatory influences on self-reinforcement behavior were investigated in 32 pre-school age children (3.1 to 5.8 years, M = 4.7 years). External conditions were two demand conditions (stringent instructional sets and lenient instructional sets). The “internal variable” was an individual differences one, motivational orientation: One-half of the children were relatively intrinsically motivated (IM) and the other half were relatively extrinsically motivated (EM). Both external and internal selfinfluences affected self-reinforcement performance on a motor/attention task. Children in the stringent-demand condition set a higher performance standard and arranged a leaner schedule of self-reinforcement than did children in the lenient-demand condition. EM children out performed IM children on measures reflecting the strength of performance (total work behavior and total time working). On measures reflecting internal standards of self-regulation, IM children set a higher performance standard in the lenient-demand condition than did EM children. Also, IM children chose a higher performance standard than modeled in the lenient-demand condition than did EM children. This experiment shows that in pre-school age children internal self-regulatory characteristics are present, well organized, and active, which interact with external demand conditions of the environment to reveal substantial individual differences in the patterns of self-reward behavior.

The reciprocal interaction of angiosperm evolution and tetrapod herbivory

We have interpreted the history of angiosperm-herbivorous tetrapod interactions based on the fossil record of the two groups. This history can be divided conveniently into four stages. Stage 1, lasting ∼ 40 Ma (Barremian-Campanian), was characterized by diverse large herbivores, few species of small herbivores, and r-selected angiosperms. The dominant interaction between herbivores and angiosperms during this stage was generalized herbivory. During Stage 2 (∼ 10 Ma, Campanian - Maestrichtian), small herbivores increased in diversity; larger angiosperms and larger angiosperm diaspores became more common. Generalized herbivory was still the dominant interaction in this stage, but frugivory/dispersal of angiosperm diaspores by small herbivores became more important. In Stage 3 (∼ 25 Ma, Paleocene - mid-Eocene) large angiosperms and large angiosperm diaspores were diverse; large herbivores were initially absent, later low in diversity. Frugivory/dispersal was common during this stage, generalized herbivory much less so. During Stage 4 (∼ 30 Ma, Oligocene - Recent), the relative importance of large vs. small herbivores and large vs. small angiosperms has varied by community, as has the relative importance of generalized herbivory vs. frugivory/dispersal. We infer the following evolutionary effects of angiosperms and tetrapods on each other. During Stage 1 generalized herbivory/disturbance by dinosaurs favored angiosperms that remained relatively small and r-selected. Increasing abundance and geographic spread of these r-selected angiosperms fueled the Late Cretaceous diversification of low-browsing ornithopod dinosaurs. The rarity of angiosperms with large diaspores provided little resource for a radiation of small herbivores. The low diversity of small herbivores created few opportunities for the evolution of small herbivore dispersal syndromes among angiosperms. The stability of angiosperm-vertebrate herbivore interactions during Stage 1 suggests this system of ecological relationships had internally self-reinforcing properties. The modest radiation of small herbivores during Stage 2 may indicate increased frugivory/dispersal. More common large angiosperm axes and diaspores show some angiosperm lines were becoming more K-selected. These imply a modification of the stable system formed during Stage 1. Extinction of all large herbivores at the K/T boundary destroyed Stage 1 ecological interactions and changed selective pressures on angiosperms. In the early Paleocene, generalized herbivory/herbivore disturbance was absent or uncommon. Denser vegetation, increased competition between plants, and increased seed dispersal/predation by small animals resulted in selection for larger seeds, diaspores and sporophytes. The distribution of resources in closed angiosperm vegetation permitted the radiation of small, arboreal, frugivorous birds and mammals, which in turn were important to the success of angiosperms with large, animal-dispersed seeds. Spread of arborescent angiosperm vegetation reduced resources and evolutionary opportunities available to larger mammalian herbivores, retarding their diversification, and in turn perpetuating low levels of generalized herbivory/disturbance. Stage 3 was another period during which angiosperm-vertebrate herbivore interactions were stabilized by self-reinforcing behavior of the system. During Stage 4 increased seasonality began to favor shorter life cycles among angiosperms; herbaceous plants diversified and spread. Open, high-productivity vegetation was better exploited by large herbivores, which diversified, increasing generalized herbivory/disturbance that in turn created more habitat for r-selected angiosperms.

複数モデノレと達成動機が児童の自己評価基準に及ぼす効果

This study investigated the effects of children's need for achievement and multiple modeling on children's self-reinforcement behavior A3x2x2 factorial design, with three modeling conditions, high or low n-ach and grades was used. The Ss were 132 third and fifth graders in a public elementary school. One-third of the Ss were exposed to a stringent-model adopting a high criterion for self-reinforcement, one-third to a lenientmodel adopting a low criterion for self-reinforcement and one-third to the above two models. The level of n-ach was determined by scores on TAT. The criteria adopted by the high n-ach children in the two-model condition were more lenient than those in the stringent-model condition and were more stringent than those in the lenient-model condition. The criteria adopted by low n-ach children were more lenient than those in the stringent-or the lenient-model condition. In the two-model condition, no significant grade differences were found in the mean number of self-administered reinforcers.

A self-reinforcement questionnaire

The hypothesis that the tendency to engage in self-reinforcement behavior is measurable by a 30-item true-false questionnaire is supported using self-monitoring as the validity criterion. The use of the self-reinforcement questionnaire has been supported previously by correlating questionnaire scores with frequency of self-reinforcement during simple experimental tasks. In the present study, 53 undergraduates monitored self-reinforcement behavior for 28 days and frequency of self-reinforcement correlated significantly with questionnaire scores as well as experimenter ratings of the tendency to engage in self-reinforcement. The results suggest that the questionnaire is a promising tool for the measurement of self-reinforcement in meaningful settings. The need for further validational evidence is noted and the potential usefulness of the questionnaire in testing hypotheses regarding the relation between self-reinforcement and depression is discussed.

Self-Reinforcement Behavior and Dimensions of Perceived Locus of Control

Self-Reinforcement Behavior and Dimensions of Perceived Locus of Control

The Effects of Induced Mood States on Selfreinforcement Behavior

Summary The influence of mood on subsequent self-reinforcement was investigated in 72 male and female college students. Feelings of elation, depression, or neutrality were induced in Ss by having them read a structured set of mood statements. Ss, assigned to either a self-reward or self-punishment condition, evaluated their performance on an ambiguous word association task by marking a self-praise or self-critical point. Ss in the elation condition awarded themselves the highest rate of praise and the lowest rate of self-criticism. Ss in the depression condition administered the highest rate of self-criticism.