Effects Of Positive Reinforcement Research Articles

Threat, Emotion Dysregulation, and Parenting in a Clinical Sample of Children with Disruptive Behaviour.

Early-life adversity is associated with the development of internalizing and externalizing problems in children. Despite this, there is a need to understand the mechanisms linking these experiences to psychopathology, especially in clinical samples. This cross-sectional study tested emotion dysregulation as a mechanism linking early-life threat to psychopathology in a clinical sample of children with disruptive behavior problems. We also explored parental positive reinforcement as a protective factor in these pathways.A clinical sample of 606 children aged 6-12years, referred to a mental healthcare hospital, were included. Parent-reported child threat, and parent- and teacher-reported child emotion dysregulation and psychopathology, were collected. Path analysis was used to explore the mediating effect of emotion dysregulation in the relation between threat and psychopathology. The moderating effects of parental positive reinforcement were explored through moderated-mediation analyses. Emotion dysregulation partially mediated the association between threat and both internalizing (β = .18, P = .006)and externalizing (β = .19, P = .002) problems. Positive reinforcement did not buffer the association between threat and emotion dysregulation (β = .09, P = .62) or the association between emotion dysregulation and internalizing (β = -.003, P = .20)or externalizing (β = -.002, P = .35). Poor emotion regulation may be a transdiagnostic mechanism linking early-threat with internalizing and externalizing problems in clinic-referred children with disruptive behaviors. Factors aside from parental positive reinforcement should be explored as protective factors in these pathways, including those directly implicated in the purported mechanisms linking these factors over time.

Graphene Nanoplatelets/Barium Titanate Polymer Nanocomposite Fibril: A Remanufactured Multifunctional Material with Unprecedented Electrical, Thermomechanical, and Electromagnetic Properties

AbstractA novel, zero‐waste and recycling plastic waste solution is introduced, to scalably produce graphene nanoplatelets/barium titanate (GNP/BaTiO3) polymer nanocomposite fibrils. A comprehensive investigation is performed to evaluate the compatible and non‐compatible recycled polypropylene (PP)/polyethyleneterephthalate (PET) blends combined with functional (electrical, piezoelectric,and dielectric) materials for in‐situ fibril production. The nanocompositefibrils made from recycled PP, PET and GNPs/BaTiO3 with high‐aspect ratio disparity (400:1) are produced, which exhibit significantly enhanced electrical, thermomechanical, and electromagnetic characteristics. Single‐screw extrusion is utilised to fabricate the fibrils with the in‐situ fibril morphology of PET and GNPs/BaTiO3 leading to improved electrical conductivity. It is demonstrated that such fibril morphology restricts the chain mobility of polymer molecules, and ultimately increases viscosity and strain energy. Moreover, the study demonstrates a positive reinforcement effect from the utilisation of PET fibrils and GNPs/BaTiO3 in a PP matrix, dominated by the high‐aspect ratio, stiffness, and thermal stability of GNPs/BaTiO3. Furthermore, it is observed that the mechanical properties and tension‐bearing capacity of the PP are significantly improved by such incorporation. The study also demonstrates that the protection of the remanufactured nanocomposites against electromagnetic interference is significantly improved with the increasing GNPs/BaTiO3 content and the morphological transition from spherical to fibril‐shaped PET.

Temperature‐dependent inter‐laminar fracture behavior of waste short carbon fiber embedded glass fiber/epoxy composites

AbstractDelamination is one of the life‐limiting failure modes for fiber reinforced polymer (FRP) composite composites resulting in poor damage tolerance, as this failure mode occurs at considerably lower loads. Owing to the enormous demand and mass production of FRP composites, a large amount of fiber waste is produced worldwide. This triggers concern about utilizing these fiber wastes for some valuable applications. The present study aims to improve the overall damage tolerance of laminated glass/epoxy composites via the introduction of waste short carbon fibers (SCFs) reinforcement in the epoxy matrix. The effect of various SCF contents (0.1, 0.3, and 0.5 wt%) in glass fiber/epoxy composites were evaluated experimentally for their interlaminar fracture toughness in terms of both crack development and propagation under mode I and II interlaminar fracture toughness tests, at elevated temperatures (30, 50, and 70°C). Based on the experimental results, glass/epoxy composite with 0.1 wt% of SCF revealed 13.49% and 20.45% increment in mode I and II interlaminar fracture toughness, respectively, at ambient temperature. A positive reinforcement effect could be noticed for GIC and GIIC values up to 50°C. However, due to residual interfacial stresses, interfacial debonding, and epoxy softening, a negative reinforcement effect could be noticed at 70°C. Delamination initiation and crack propagation mechanisms have been explored at elevated temperatures. Fractographic studies have been carried out using a scanning electron microscope to identify the failure mechanisms.

Attenuation of the Positive-Reinforcing Effects of Ultra-Potent Fentanyl Analogs, Along with Those of Fentanyl and Heroin, During Daily Treatment with Methocinnamox in Rhesus Monkeys.

Without substantial intervention, the opioid crisis is projected to continue, underscoring the need to develop new treatments for opioid use disorder (OUD). One drug under development is the µ opioid receptor antagonist methocinnamox (MCAM), which appears to offer advantages over currently available medications; however, some questions remain about its potential utility, including its ability to block the effects of ultra-potent fentanyl analogs. The goal of this study was to examine its effectiveness in attenuating the abuse-related effects of the fentanyl analogs carfentanil and 3-methylfentanyl in monkeys responding for food or intravenous infusions under a choice procedure. These drugs were compared with fentanyl, heroin, methamphetamine, and cocaine. Food was preferred over saline, and there was a dose-dependent increase in responding for drug over food with no marked decrease in response rates or number of choice trials completed for any of the six drugs studied. Naltrexone (0.032 mg/kg) antagonized choice of µ opioid receptor agonists, producing rightward shifts in dose-effect curves ranging from 27-fold (carfentanil) to 71-fold (heroin). In contrast, naltrexone was less effective in attenuating choice of methamphetamine or cocaine with curves obtained in the presence of naltrexone shifted <3-fold. Daily treatment with 0.032 mg/kg MCAM also antagonized the effects of opioids, shifting curves 20-fold (fentanyl) to 72-fold (heroin) rightward; MCAM did not significantly change dose-effect curves for methamphetamine or cocaine. Thus, antagonism by MCAM is similar across a variety of µ opioid receptor agonists, including ultra-potent fentanyl analogs, further supporting its potential utility as a treatment for OUD. SIGNIFICANCE STATEMENT: Treatments for opioid use disorder (OUD) should attenuate the effects of a variety of opioids, including emerging threats like the ultra-potent fentanyl analogs. The novel µ opioid receptor antagonist MCAM is being developed to treat OUD because it provides long-lasting blockade of the reinforcing effects of heroin and fentanyl. The current study shows that MCAM attenuates the abuse-related effects of the fentanyl analogs carfentanil and 3-methylfentanyl, further supporting the utility of MCAM as a treatment for OUD.

Role of risk perception and government regulation in reducing over-utilization of veterinary antibiotics: Evidence from hog farmers of China

Antibiotic residues and resistance caused by farmers' overuse of veterinary antibiotics have severely damaged global food safety, the ecological environment, and public health. How to lessen the overutilization of antibiotics is of prime concern nowadays; however, the existing literature has paid little attention. So, to fill this gap, the current study explores the role of risk perception and government regulation in reducing the over-utilization of veterinary antibiotics by gathering data from 675 hog farmers in the Hebei, Henan, Hubei, and Shandong provinces of China. The Heckman two-stage model is employed to explore the phenomenon. Meanwhile, risk perception is categorized into food security risk perception (FSRP), ecological security risk perception (ESRP), and public health risk perception (PHRP), and government regulation is measured from antibiotic prescribed policy (APP), withdrawal period policy (WPP), and antibiotic recorded policy (ARP). The results showed that the PHRP (ODC: ME = -0.073, SE = 0.018; ODG: ME = -0.125, SE = 0.047) significantly inhibits farmers' overuse of antibiotics. In contrast, the ESRP and PHRP have not shown significant results in influencing farmers' overuse of antibiotics. Moreover, the APP (ODC: ME = -0.035, SE = 0.016; ODG: ME = -0.088, SE = 0.040) and WPP (ODC: ME = -0.072, SE = 0.039; ODG: ME = -0.175, SE = 0.097) significantly reduce antibiotics overuse, but the influence of the ARP on farmers' antibiotics overuse is not apparent. Further, a moderating effect model is used to analyze the moderating effect of government regulation on farmers' overuse of antibiotics influenced by risk perception. The results showed that the APP (ODC: ME = -0.041, SE = 0.012; ODG: ME = -0.075, SE = 0.018) and WPP (ODC: ME = -0.058, SE = 0.015; ODG: ME = -0.076, SE = 0.019) positively influence farmers' overuse of antibiotics impacted by public health risk perception. In contrast, the ARP has no positive reinforcement effect. Finally, the study proposes that government should devolve the supervision power to veterinarians, strengthen the regulation policy advocacy, conduct training programs for farmers regarding skills to use antibiotics, and strengthen biosafety measures.

Reinforcement positif : Teknik untuk Meningkatkan Academic Engagement Siswa pada Pandemi Covid-19

Academic engagement is important for the smooth learning process. However, in fact the involvement of students in the learning process is minimal. This study aims to determine the effectiveness of positive reinforcement to increase student academic engagement. This study is a single case experimental design, with an A-B-A design research involving one student at Global Madani Junior High School who has low academic engagement. The instrument used in this intervention is an academic engagement rating scale based on the research of Schreiner &amp; Louis. Analysis of the data used is statistical analysis and clinical analysis. The results showed a significant increase in academic engagement through positive reinforcement on scores at baseline A1, intervention, and baseline A2. Teachers and counselors can use various kinds of positive reinforcement to make students actively involved in the learning process.

The role of market competition for knowledge competencies, R&amp;D and innovation: an empirical analysis for German firms

PurposeKnowledge competencies and (R&amp;D) activities are one of the most important sources of innovation and have been widely discussed in the literature. In comparison, the role of the competitive environment for the innovation activities of firms is still open to debate and has not been fully understood yet. Therefore, this paper intends to provide new evidence on the interaction between knowledge competencies and R&amp;D activities of firms on the one side and their competitiveness in the market environment on the other. In particular, the moderating function of market competition is explored. In this respect, the analysis covers the main innovation types as well as both sectors, manufacturing and services.Design/methodology/approachThe empirical analysis is based on a three years panel dataset of German manufacturing and service firms obtained from Mannheim Innovation Panel (MIP) and Community Innovation Surveys (CISs: 2011, 2013 and 2015). For the estimation, a binary instrumental variable treatment model with Heckman selection method is used. Also, it provides a suitable approach to estimating the binary variables in order to cope with endogeneity concerns.FindingsThe estimation results show that R&amp;D activities and knowledge competencies are positively related to innovation activities of different types conditioned on firms' specific perception of their competitive environment, in terms of outdated products/services as well as strong competition from abroad. Most importantly, the results from the moderation estimation reveal that there is a significant difference between the manufacturing and service sector. Service firms engage more in internal R&amp;D activities on generating product innovations while the manufacturing firms conduct more external R&amp;D on specific types of innovation. Further, the authors find that strong competition from abroad positively and significantly reinforces the effect of knowledge competencies on innovation activities for more types in services than in manufacturing. In contrast, outdated products and services tend to decline the effect of knowledge competencies for some innovation types in both sectors. The authors also observe a positive and significant reinforcement effect on knowledge competencies. However, it is found more beneficial for service firms since they can employ more innovation strategies.Originality/valueThe focus of the study is mainly on the impact of firms' competitive environment on innovation activities in various types through its interaction with knowledge competencies and R&amp;D activities, across manufacturing and service firms.

Research on the Emotional Evolution Mechanism of Network Public Opinion Based on an Information Ecosystem

As an important carrier of public emotion expression, public opinion spreads on a large scale with the continuous upgrading of social networks, and effectively controlling the spreading process of public opinion is an essential topic of contemporary social research. In view of the competition between positive and negative information in the process of public opinion dissemination, this paper introduces the theory of emotional infection and proposes a network public opinion communication model based on emotional contagion, considering the reinforcement effect of different individual mentalities and the influence of government intervention. Based on the data from the COVID-19 epidemic situation, MATLAB simulation technology is used to verify the validity of the model, and the effect of strengthening the validity and government intervention on public opinion control is discussed. According to the experiment, three conclusions have been come up with. First, a positive reinforcement effect can enhance the ignorant participants’ ability to maintain the same emotion as the infected information. When positive information repeatedly stimulates the ignorant, it will positively strengthen the ability of people with a positive mentality to maintain positive emotions, which is significantly beneficial to public opinion control. Its essence is to increase the effect of positive information’s belief factor on the dynamic infection rate. When negative information repeatedly stimulates an ignorant person, it will positively strengthen the ability of the person with a negative attitude to maintain negative emotion, which is not conducive to public opinion control. Second, a negative reinforcement effect will strengthen the ignorant ability to change the same emotion as the infected information. When negative information repeatedly stimulates the ignorant, the negative reinforcement effect will strengthen the positive people’s ability to change negative information into positive emotion, which is significantly beneficial to public opinion control. Its essence is to increase the effect of suspicion factor on the dynamic immunization rate. It will strengthen the positive mentality and negative mentality into the path of immunization, which is beneficial to epidemic control. When positive information repeatedly stimulates the ignorant, it will negatively strengthen the ability of the negative mentality to change the positive information into negative emotions, which is not beneficial to the control of public opinion. It will be harmful to strengthen the path of positive and negative mentality into immunization, which is beneficial to epidemic control. Third, the earlier the government intervenes in public opinion, the better it will be. The essence of intervention is to decrease the dynamic incitement rate.

The effect of positive reinforcement of behavioral-based safety on safety participation in Philippine coal-fired power plant workers: a partial least squares structural equation modeling approach

The power plant accident is considered one of the man-made disasters in many developing countries, including the Philippines. This study aimed to identify the factors influencing behavioral-based safety (BBS) of coal-fired power plant workers which subsequently led to their active safety participation (SPT). In total, 201 coal-fired power plant workers in the Philippines answered the questionnaire consisting of 60 items using a purposive sampling approach. Partial least squares structural equation modeling (PLS-SEM) revealed that personal measures (PM) had significant effects on safety incentives (SI), safety management system (SMS) and safety perception (SP). SP also had significant effect on BBS which subsequently led to SPT. Finally, SMS had significant effect on safety culture (SC) which subsequently led to safety communication (SCM), BBS and SPT. This study is the first to explore BBS in the Philippine coal-fired power plant, and can positively reinforce SPT of workers in the coal-fired power plant industry.

The Effects of Positive Reinforcement on Students’ Writing Achievement in an Indonesian EFL Classroom

This research was aimed to find out the effects of positive reinforcement on students’ writing achievement and the students’ perception about the implementation of positive reinforcement. This research design used a quasi-experimental design. A quasi-experimental design is the design of experiment that use two classes that were investigated. The concept of quasi-experimental design there were two groups, experiment class and control class. The total of sample were 48 students consisted of 24 students for experiment class and 24 students for control class and this research applied cluster random sampling. The instruments used were tests and questionnaires. The results of the research showed: (1) there was a significant effect of positive reinforcement on students’ writing achievement. (2) the students have positive perception about the implementation of positive reinforcement in teaching writing.

The Effect Of Positive And Negative Reinforcement On An Induced Stress Response In University Students

IntroductionStress in a university setting is known to poorly affect academic performance, increase blood pressure levels, and increase the risk of cardiovascular disease. However, the effect of positive and negative reinforcement on students and its ability to induce a stress or physiological response is unknown. The objective of this study is to examine the effects of positive and negative reinforcement on an induced stress response, and how this affects their typing abilities.Methods15 participants (6 male, 9 female) underwent a series of 2 typing tests, with verbal feedback elicited prior to commencing the second test. Participants ages 18 to 22 were recruited from Joseph S. Stauffer Library at Queen’s University and randomly allocated between 3 groups: positive, negative and a control. Blood pressure was measured 5 times across the duration of the 15-minute study for each participant. A one-way ANOVA test was used to identify if there were statistically significant differences between the groups. All analyses were completed using SPSS Version 27.ResultsNegative reinforcement (-11 mmHg) versus control (-5.4 mmHg) elicited a statistically significant increase in systolic blood pressure (SBP) and rate-pressure product (p &lt; 0.05, p &lt; 0.05, respectively). No significant differences were found between groups in typing test scores, diastolic blood pressure, and heart rate. Qualitative analysis determined that negative feedback decreased confidence while increasing performance; positive reinforcement increased both confidence and performance.ConclusionThe study concluded that positive reinforcement should be implemented in university-level courses as it was found to increase typing performance while decreasing SBP.&#x0D; Keywords: reinforcement, stress, blood pressure, typing, students

Application of the Positive Reinforcement to Enhance the Learnability of EFL Learners

The article aims to explore the effectiveness of positive reinforcement in EFL (English as a foreign language) classrooms with the situations of enhancing the learnability of EFL learners. For the concern, I applied positive reinforcement to one section of class 11 for a month, and to another section of the same class, there was no treatment after the treatment post-test was administered in the two groups. From the data, the group in which the treatment applied was found better motivation in learning; as a result, they can enhance learnability and develop a friendly situation in learning English. Therefore, positive reinforcement enhances the learnability of the learners, and they can develop the level of confidence, the horizon of knowledge, and cooperative learning strategies in the EFL situation.

Hydrothermal Ageing Effect on Reinforcement Efficiency of Nanofibrillated Cellulose/Biobased Poly(butylene succinate) Composites.

Nanofibrillated cellulose (NFC) is a sustainable functional nanomaterial known for its high strength, stiffness, and biocompatibility. It has become a key building block for the next-generation of lightweight, advanced materials for applications such as consumer products, biomedical, energy storage, coatings, construction, and automotive. Tunable and predictable durability under environmental impact is required for high performance applications. Bio-based poly (butylene succinate) (PBS) composites containing up to 50% NFC content were designed and aged in distilled water or at high relative humidity (RH98%). PBS/NFC composites are characterized by up to 10-fold increased water absorption capacity and diffusivity and the data are correlated with model calculations. Aged samples exhibited decreased crystallinity and melting temperature. Incorporation of NFC into PBS showed up to a 2.6-fold enhancement of the elastic modulus, although accompanied by a loss of strength by 40% and 8-fold reduction in the strain at failure of maximally loaded composites. Hydrothermal ageing had almost no influence on the tensile characteristics of PBS; however, there were considerable degradation effects in PBS/NFC composites. Altered reinforcement efficiency is manifested through a 3.7-fold decreased effective elastic moduli of NFC determined by applying the Halpin–Tsai model and a proportional reduction of the storage moduli of composites. The adhesion efficiency in composites was reduced by hydrothermal ageing, as measured Puckanszky’s adhesion parameter for the strength, which decreased from 3 to 0.8. For the loss factor, Kubat’s adhesion parameter was increased by an order. PBS filled with 20 wt.% NFC is identified as the most efficient composition, for which negative environmental degradation effects are counterbalanced with the positive reinforcement effect. The PBS matrix can be used to protect the NFC network from water.

Exploring the bone regeneration potential of bio-fabricated nano-titania reinforced polyvinyl alcohol / nano-cellulose based composite film

A significant rise in bone-related defects affects the quality of life which impels researchers to facilitate the new approaches for bone regeneration. Herein, we have explored the bioactive nature of nano-titania for its utilization in bone tissue engineering. The titania-doped ternary nanocomposite film (PVA/NC-TiO2) was prepared by the fusion of Polyvinylalcohol (PVA), nano-cellulose (NC), and TiO2 (0.01 wt%) nanoparticles via sol-gel casting and compared with its binary nanocomposite film (PVA/NC). The simple and low-cost synthesis of these nanocomposite films, together with remarkable bioactive and thermo-mechanical properties, makes them a good candidate for their applications in human bone regeneration. The fabricated nanocomposite films were characterized through Fourier transform infra-red, Ultra-violet spectroscopy, and X-ray diffraction analysis to study complex formation and intermolecular interactions between the molecular entities.The SEM and TEM micrographs revealed the smooth surface of the developed binary and ternary nanocomposite films along with homogenous particle distribution. The thermo-mechanical stability was significantly improved when the nanocomposite film was modified with TiO2 nanoparticles indicating an enhancement of intermolecular interactions in PVA/NC-TiO2 film as compared to PVA/NC film. The Dynamic mechanical analysis results show higher storage modulus and glass transition temperature for PVA/NC-TiO2 film (9131.26 MPa, 74.3 °C) than PVA/NC film (7588 MPa, 64.3 °C). A comparative analysis of nanocomposite films revealed that PVA/NC-TiO2 film exhibited a thick and more uniformed layer of Ca–P mineral on its surface than PVA/NC film when incubated in Simulated Buffer Saline. The low loading of TiO2 nanoparticles resulted in a positive reinforcement effect on the bioactivity of the PVA/NC-TiO2 film (cell viability higher than 80%, hemolysis less than 1.7%) which provides an effective gateway for polymer nanocomposites in the dynamic orthopedic application by serving a better bone template for the regeneration of bone tissue.

Caveolin-1 Expression in the Dorsal Striatum Drives Methamphetamine Addiction-Like Behavior.

Dopamine D1 receptor (D1R) function is regulated by membrane/lipid raft-resident protein caveolin-1 (Cav1). We examined whether altered expression of Cav1 in the dorsal striatum would affect self-administration of methamphetamine, an indirect agonist at the D1Rs. A lentiviral construct expressing Cav1 (LV-Cav1) or containing a short hairpin RNA against Cav1 (LV-shCav1) was used to overexpress or knock down Cav1 expression respectively, in the dorsal striatum. Under a fixed-ratio schedule, LV-Cav1 enhanced and LV-shCav1 reduced responding for methamphetamine in an extended access paradigm compared to LV-GFP controls. LV-Cav1 and LV-shCav1 also produced an upward and downward shift in a dose–response paradigm, generating a drug vulnerable/resistant phenotype. LV-Cav1 and LV-shCav1 did not alter responding for sucrose. Under a progressive-ratio schedule, LV-shCav1 generally reduced positive-reinforcing effects of methamphetamine and sucrose as seen by reduced breakpoints. Western blotting confirmed enhanced Cav1 expression in LV-Cav1 rats and reduced Cav1 expression in LV-shCav1 rats. Electrophysiological findings in LV-GFP rats demonstrated an absence of high-frequency stimulation (HFS)-induced long-term potentiation (LTP) in the dorsal striatum after extended access methamphetamine self-administration, indicating methamphetamine-induced occlusion of plasticity. LV-Cav1 prevented methamphetamine-induced plasticity via increasing phosphorylation of calcium calmodulin kinase II, suggesting a mechanism for addiction vulnerability. LV-shCav1 produced a marked deficit in the ability of HFS to produce LTP and, therefore, extended access methamphetamine was unable to alter striatal plasticity, indicating a mechanism for resistance to addiction-like behavior. Our results demonstrate that Cav1 expression and knockdown driven striatal plasticity assist with modulating addiction to drug and nondrug rewards, and inspire new strategies to reduce psychostimulant addiction.

Cannabinoid receptor type 1 antagonists alter aspects of risk/reward decision making independent of toluene-mediated effects.

Drugs of abuse including cannabis and inhalants impair risk/reward decision making. Cannabis use is often concurrent with inhalant intoxication; yet, preclinical studies investigating the role of endocannabinoids in inhalant misuse are limited. To address this gap in the literature, we used the well-validated probabilistic discounting task to assess risk/reward decision making in rodents following combinations of toluene vapor (a common inhalant) and manipulations of cannabinoid receptor type 1 (CB1R) signaling. As reported previously, acute exposure to toluene vapor disrupted behavioral flexibility during probabilistic discounting. Systemic administration of the CB1R inverse agonist AM281 did not prevent toluene-induced alterations in risky choices, but did independently reduce win-stay behavior, increase choice latency, and increase omissions. Toluene-induced deficits in probabilistic discounting are thought to involve impaired medial prefrontal cortex (mPFC) activity. As we previously reported that some of toluene's inhibitory effects on glutamatergic signaling in the mPFC are endocannabinoid-dependent, we tested the hypothesis that mPFC CB1R activity mediates toluene-induced deficits in discounting. However, bilateral injection of the CB1R inverse agonist AM251 prior to toluene vapor exposure had no effect on toluene-induced changes in risk behavior. In a final set of experiments, we injected the CB1R inverse agonist AM251 (5 and 50ng), the CB1R agonist WIN55,212-2 (50ng and 500ng), or vehicle into the mPFC prior to testing. While mPFC CB1R stimulation did not affect any of the measures tested, the CB1R inverse agonist caused a dose-dependent reduction in win-stay behavior without altering any other measures. Together, these studies indicate that toluene-induced deficits in probabilistic discounting are largely distinct from CB1R-dependent effects that include decreased effectiveness of positive reinforcement (mPFC CB1Rs), decision making speed, and task engagement (non-mPFC CB1Rs).

Astrocytes mediate the effect of oxytocin in the central amygdala on neuronal activity and affective states in rodents.

Oxytocin (OT) orchestrates social and emotional behaviors through modulation of neural circuits. In the central amygdala, the release of OT modulates inhibitory circuits and, thereby, suppresses fear responses and decreases anxiety levels. Using astrocyte-specific gain and loss of function and pharmacological approaches, we demonstrate that a morphologically distinct subpopulation of astrocytes expresses OT receptors and mediates anxiolytic and positive reinforcement effects of OT in the central amygdala of mice and rats. The involvement of astrocytes in OT signaling challenges the long-held dogma that OT acts exclusively on neurons and highlights astrocytes as essential components for modulation of emotional states under normal and chronic pain conditions.

Efeitos de reforçadores de magnitude aumentada e do controle aversivo na manutenção do seguimento de regras em estudantes universitários

Este estudo avaliou os efeitos da magnitude aumentada do reforço positivo (ganho de pontos) e do controle aversivo (perda de pontos) no seguimento de regras. Participaram 16 universitários expostos a uma tarefa de matching-to-sample. Os participantes, divididos em dois grupos, deveriam selecionar um de dois estímulos-comparação na presença de um estímulo contextual. No Grupo Ganho, iniciava-se a sessão com zero pontos e cada acerto produzia três pontos; no Grupo Perda, iniciava-se a sessão com 80 pontos e cada erro produzia a perda de um ponto. Foram realizadas 80 tentativas divididas em quatro blocos. Nos Blocos C1 e C2, as contingências eram correspondentes às regras; nos Blocos D1 e D2 eram discrepantes. O Grupo Perda apresentou média de acertos significativamente maior que o Grupo Ganho nos blocos discrepantes. A magnitude aumentada do reforço não se igualou aos efeitos do controle aversivo em relação ao abandono do seguimento de regras, confirmando estudos prévios.

Theoretical Substantiation of the Foam Concrete Strength Formation Laws

A detailed theoretical analysis of the processes occurring in foam concrete mixtures in the period between their laying in the mold and the phase transition “from viscous to solid” completion moment. The stages of the formation of inter-pore septa in foam concrete mixtures, depending on the material nature and shape of the solid dispersed particles of raw materials, are sequentially considered. It is shown that their shape affects the mass transfer rate and the density of inter-pore septa during the structure formation. The reasons for the fluctuations in the elasticity of foam films during the predominance period of viscous bonds between the components of the raw material are described. The gas inclusions factors of influence on the dispersion parameters and, as a consequence, the aggregative stability of foam mixtures, are ranked. The positive dispersed reinforcement effect on the mass transfer processes in mixtures and the hardened concrete strength is substantiated.

Investigation on the Flexural-Tensile Rheological Behavior and Its Influence Factors of Fiber-reinforced Asphalt Mortar.

On the basis of a modified three-dimensional (3D) random distribution fiber model, this study further investigates the flexural–tensile rheological behavior and its influence factors of fiber-reinforced asphalt mortar. First, the viscoelastic creep at a temperature of 15 °C for pure asphalt mortar as the control sample are obtained by the beam bending creep test to fit the Burgers constitutive parameters. Second, a 3D numerical model consisting of a homogeneous asphalt mortar matrix with viscoelastic parameters and short and straight fibers with elastic characteristics is built in a cuboid space on the basis of a fiber algorithm to simulate the flexural–tensile rheological behavior using ABAQUS software, and the rheological behavior of the 3D model is consistent with those of the test result. Finally, 3D numerical simulations are conducted to further analyze the effect of fiber factors (e.g., contents, aspect ratios, modulus, and fiber types) on the rheological behavior. Results show that the effect of basalt fiber (BF) compared with steel wool fiber are more significant, and increasing fiber contents and aspect ratios have a positive reinforcement effect on the rheological behavior, where BF content for 0.1%, 0.2%, and 0.3% at 3600 s compared with the control reduced by 37.5%, 53%, and 61.7%, and BF aspect ratios for 30, 40, and 50 compared with that for 20 increased by 4.3%, 16.1%, and 32.9%, respectively, but the change in fiber modulus has a minimal impact.