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Co-design in preclinical skill-based learning: A pandemic plan for continuity and reinforcement

Saxena K, Arunachalam S, Banavar SR, Dhanaraj S

J Dent Educ, 2022 Dec;86 Suppl 3:1731-1733.
PMID: 34958485 DOI: 10.1002/jdd.12872
Fulltext Application of reinforcement learning in cognitive radio networks: models and algorithms

Yau KL, Poh GS, Chien SF, Al-Rawi HA

ScientificWorldJournal, 2014;2014:209810.
PMID: 24995352 DOI: 10.1155/2014/209810

Cognitive radio (CR) enables unlicensed users to exploit the underutilized spectrum in licensed spectrum whilst minimizing interference to licensed users. Reinforcement learning (RL), which is an artificial intelligence approach, has been applied to enable each unlicensed user to observe and carry out optimal actions for performance enhancement in a wide range of schemes in CR, such as dynamic channel selection and channel sensing. This paper presents new discussions of RL in the context of CR networks. It provides an extensive review on how most schemes have been approached using the traditional and enhanced RL algorithms through state, action, and reward representations. Examples of the enhancements on RL, which do not appear in the traditional RL approach, are rules and cooperative learning. This paper also reviews performance enhancements brought about by the RL algorithms and open issues. This paper aims to establish a foundation in order to spark new research interests in this area. Our discussion has been presented in a tutorial manner so that it is comprehensive to readers outside the specialty of RL and CR.

Matched MeSH terms: Reinforcement (Psychology)*
Fulltext Carbon nanotubes reinforced aluminum matrix composites - a review of processing techniques

Toozandehjani, Meysam, Khamirul Amin Matori, Ostovan, Farhad, Sidek Abdul Aziz, Md Shuhazely Mamat, Oskoueian, Arshin

The Pertanika Journal of Scholarly Research Reviews, 2017;3(1):70-92.
MyJurnal

Carbon nanotube reinforced aluminium matrix composites (Al-CNTs) have been widely used in aerospace and automotive industries where high quality and strength is required. The enhanced mechanical properties of Al-CNTs are closely related to processing technique due to challenges within production of these composite materials. In the current review, solid state processing techniques used for synthesizing Al-CNTs have been reviewed to provide an insight into the features and capabilities of each technique regarding the incorporation of CNT reinforcements. To conclude, the mechanical performance of Al-CNT composites is mainly decided by the capability of each technique in the dispersion of CNTs within the aluminum matrix.
Fulltext Deficient reinforced concretebeam-column joint strengthening

Mohammed, Kachalla, Kareem, Shatha Sahib

The Pertanika Journal of Scholarly Research Reviews, 2018;4(3):11-25.
MyJurnal

Structural buildings in seismic prone area, the required energy dissipation of strong column-weak beam especially for reinforced concrete frame structures is achievably through adequate beam-column joint strengthening connection in order to have high seismic performance. Literature investigation shows several approaches and techniques for modelling the weak joint for a typical frame structure. This paper extensively reviews those techniques, methods, concepts and their performance in improving the shear capacity for a deficient reinforced concrete beam-column joints in withstanding seismic loads. The beam-column joints performance responses showed positive. However, the need for an improved connection that will offer high ductility capacity and energy dissipation ability for post-tensioned reinforced concrete beam-column joints with continuing bottom reinforcement is highly feasible with the use of the Direct Displacement Based design philosophy. This will be of great interest for the future development of highly efficient joint system for frame structure capable of resisting significant seismic load.
Fulltext Conditional Learning Deficits in Children with ADHD can be Reduced Through Reward Optimization and Response-Specific Reinforcement

De Meyer H, Tripp G, Beckers T, van der Oord S

Res Child Adolesc Psychopathol, 2021 09;49(9):1165-1178.
PMID: 33792820 DOI: 10.1007/s10802-021-00781-5

When children with ADHD are presented with behavioral choices, they struggle more than Typically Developing [TD] children to take into account contextual information necessary for making adaptive choices. The challenge presented by this type of behavioral decision making can be operationalized as a Conditional Discrimination Learning [CDL] task. We previously showed that CDL is impaired in children with ADHD. The present study explores whether this impairment can be remediated by increasing reward for correct responding or by reinforcing correct conditional choice behavior with situationally specific outcomes (Differential Outcomes). An arbitrary Delayed Matching-To-Sample [aDMTS] procedure was used, in which children had to learn to select the correct response given the sample stimulus presented (CDL). We compared children with ADHD (N = 45) and TD children (N = 49) on a baseline aDMTS task and sequentially adapted the aDMTS task so that correct choice behavior was rewarded with a more potent reinforcer (reward manipulation) or with sample-specific (and hence response-specific) reinforcers (Differential Outcomes manipulation). At baseline, children with ADHD performed significantly worse than TD children. Both manipulations (reward optimization and Differential Outcomes) improved performance in the ADHD group, resulting in a similar level of performance to the TD group. Increasing the reward value or the response-specificity of reinforcement enhances Conditional Discrimination Learning in children with ADHD. These behavioral techniques may be effective in promoting the learning of adaptive behavioral choices in children with ADHD.
Fulltext Effect of adding polystyrene into coconut meat husk fiber reinforced polyester composites on the tensile properties

Mohd Adib Mohd Aini, Mohamad Juraidi Jamal, Syed Azuan Syed Ahmad

Journal of Engineering and Science Research, 2017;1(1):1-3.
MyJurnal

The purpose of this study is to compare the tensile strength between additional polystyrene into coconut meat husk reinforced fiber composite. Composite were produced by using hand layup technique. It is seen that with the additional of polystyrene into the coconut meat husk reinforced polyester composites showed the increment tensile strength value compared to the non-added polystyrene which indicates that effective stress transfer between the fiber, matrix and polystyrene.
Fulltext Kenaf fibre and its bio-based composites: a conspectus

Adole, Adole Michael, Jamaludin Mohamad Yatim, Suhaimi Abubakar Ramli, Athirah Othman, Norazura Azzmi Mizal

Pertanika Journal of Science & Technology, 2019;27(1):297-329.
MyJurnal

(Kenaf fibre is a good reinforcement in fibre polymer composites due to its high strength
and elastic modulus, high stiffness, low density, low cost and eco-efficient, less health
hazards, renewability, good mechanical and thermal properties, and biodegradability. It is
traditionally used for rope, twine, fish net and sacking materials. Recently, it was observed
that kenaf fibre had huge potentials to replacing synthetic fibre in composites due to the
rising environmental and ecological issues, thus this awareness has motivated efforts for
the advancement of new innovative bio-based composites incorporating kenaf fibre for
various end-use structural applications. This paper presents an overview of the development
made so far in the area of kenaf fibre and its composites in terms of chemical and microstructural
properties, mechanical properties, dimensional stability, thermal stability, product
development and application. Some fundamental issues and suggestions for further research
in this area are also discussed.
Fulltext Effects of nicotine on schizophrenia and antipsychotic medications: a systematic review

Hamira Farahana Hamdan, Syahrir Zaini

Malaysian Journal of Psychiatry, 2018;27(1):0-0.
MyJurnal

Majority people with schizophrenia who smoke cigarettes, tend to be heavy smokers than other psychiatric patients and general population. Nicotine is one of the main components of cigarettes that can produce nicotinic interactions with antipsychotic drugs. Nicotine can also alleviate psychotic symptoms of schizophrenia. Aim: The objective for this systematic review is to examine the effects of nicotine and nicotine-based products in the treatment of schizophrenia, in comparison with placebo, no treatment or antipsychotic medication. Results: All studies comparing nicotine or other related products as the only treatment or adjunctive treatment for schizophrenia patients excluding the animal studies and case studies are reviewed. The use of traditional or known as typical antipsychotics may cause the patients to smoke frequently while patients taking atypical antipsychotics may smoke less. Patients who smoke may metabolize antipsychotics faster than non-smoking patients. There is less report related to smoking cessation among the schizophrenia patients. Conclusion: Neurobiological and psychosocial factors reinforce the high use of nicotine by patients with schizophrenia. Prior to smoking cessation implementation, it is crucial to understand on the ways and reasons for schizophrenia patients to consume nicotine for self-medicate symptoms which may lead to the development of new treatments for schizophrenia and nicotine dependence.
Value, drug addiction and the brain

Loganathan K, Ho ETW

Addict Behav, 2021 05;116:106816.
PMID: 33453587 DOI: 10.1016/j.addbeh.2021.106816

Over the years, various models have been proposed to explain the psychology and biology of drug addiction, built primarily around the habit and compulsion models. Recent research indicates drug addiction may be goal-directed, motivated by excessive valuation of drugs. Drug consumption may initially occur for the sake of pleasure but may transition to a means of escaping withdrawal, stress and negative emotions. In this hypothetical paper, we propose a value-based neurobiological model for drug addiction. We posit that during dependency, the value-based decision-making system in the brain is not inactive but has instead prioritized drugs as the reward of choice. In support of this model, we consider the role of valuation in choice, its influence on pleasure and punishment, and how valuation is contrasted in impulsive and compulsive behaviours. We then discuss the neurobiology of value, beginning with the dopaminergic system and its relationship with incentive salience before moving to brain-wide networks involved in valuation, control and prospection. These value-based neurobiological components are then integrated into the cycle of addiction as we consider the development of drug dependency from a valuation perspective. We conclude with a discussion of cognitive interventions utilizing value-based decision-making, highlighting not just advances in recalibrating the valuation system to focus on non-drug rewards, but also areas for improvement in refining this approach.
Fulltext The Feedback-Related Negativity and the P300 Brain Potential Are Sensitive to Price Expectation Violations in a Virtual Shopping Task

Schaefer A, Buratto LG, Goto N, Brotherhood EV

PLoS One, 2016 09 22;11(9):e0163150.
PMID: 27658301 DOI: 10.1371/journal.pone.0163150

A large body of evidence shows that buying behaviour is strongly determined by consumers' price expectations and the extent to which real prices violate these expectations. Despite the importance of this phenomenon, little is known regarding its neural mechanisms. Here we show that two patterns of electrical brain activity known to index prediction errors-the Feedback-Related Negativity (FRN) and the feedback-related P300 -were sensitive to price offers that were cheaper than participants' expectations. In addition, we also found that FRN amplitude time-locked to price offers predicted whether a product would be subsequently purchased or not, and further analyses suggest that this result was driven by the sensitivity of the FRN to positive price expectation violations. This finding strongly suggests that ensembles of neurons coding positive prediction errors play a critical role in real-life consumer behaviour. Further, these findings indicate that theoretical models based on the notion of prediction error, such as the Reinforcement Learning Theory, can provide a neurobiologically grounded account of consumer behavior.
Fulltext Energy absorption and morphological characteristics of opened-cell green rubber foam at different recycled carbon fiber loading

Mazliah, M., Noraiham, M., Anisah, A.L., Azrul, Y., Hairul, E.A.M., Jeefferie, A.R., et al.

Malaysian Journal of Microscopy, 2015;11(1):56-60.
MyJurnal

Incineration and disposal of carbon fiber waste from the aircraft industry lead to serious energy consumption and environmental pollution. The use of this waste as reinforcement is a wise approach to appreciate the high performance of the carbon fiber. This study is part of our effort to develop new green rubber foam from recycled carbon fiber prepreg (rCFP) reinforced natural rubber via internal mixer. It is focusing on the effect of different rCFP loading at 1, 3, 5, and 7 parts per hundred rubbers (phr) as reinforcement. The samples were prepared by melt compounding using an internal mixer and expanded via two step heat transfer foaming process. The physical properties of the green rubber foam were characterized and the results were observed to systematically correlate with the impact properties of the foam. The absorbed energy of the foam increases up to 0.3 joules with increasing relative foam density of 0.81 which is associated with the formation of smaller foam cells ~0.68mm and more spherical shape pores.
Ability to Resist Temptations of Technology Use: A Qualitative Analysis of Children's Views on Factors Associated with Delay of Gratification

Ang CS, Lee KF

J Genet Psychol, 2017 Sep-Oct;178(5):291-297.
PMID: 28961083 DOI: 10.1080/00221325.2017.1355773

Excessive technology use among young children remains a public health concern with diverse serious consequences. It is important to find out how children resist the temptation to use technology. Using focus group interviews, the authors explored what factors influence children's ability to delay gratification in using technology. Four specific themes emerged from the interview data: they found (a) fear of punishment, (b) self-directed speech, (c) reinforcement, and (d) parental modeling are effective measures to train children to forgo immediate pleasures of using technology. These findings provided some support for the hypothesis that children's self-control of technology use can be modified and improved. This study suggests methods to leverage and strengthen existing initiatives to promote self-control of technology use for children.
Fulltext The effectiveness of the community reinforcement approach (CRA) in the context of quality of life and happiness among people using drugs

Khalid MT, Khalily MT, Saleem T, Saeed F, Shoib S

Front Public Health, 2024;12:1229262.
PMID: 38504677 DOI: 10.3389/fpubh.2024.1229262

INTRODUCTION: The Community Reinforcement Approach is an evidence-based treatment modality for alcohol and drug addiction treatment with proven efficacy and cost-effectiveness. The present study investigated the effectiveness of the Community Reinforcement Approach (CRA) in the context of quality of life among drug addicts.
MATERIALS AND METHODS: A total of 60 inpatient substance abusers post detoxification in Fountain House, Lahore, Pakistan, participated in this study. Fountain House was selected as the Minnesota model is primarily used there. Therefore, a new treatment approach was introduced to investigate its effectiveness for individuals with substance abuse. A randomized 12-week trial was conducted as a substance use disorders (SUDs) treatment program. Persons with SUD (i.e., identified patients) enrolled in a residential treatment program were randomized into the integrated model of the Community Reinforcement Approach (CRA) and traditional Minnesota model treatment (n = 30), and traditional Minnesota model treatment only (TMM; n = 30). All the participants in the experimental group attended the group therapy sessions and other activities in the facility in addition to the treatment conditions. The participants attended the individual therapeutic sessions, which were conducted according to the CRA guidelines used in the experimental group. In this study, each individual in the CRA treatment group received 12 one-to-one sessions ranging from 45 min to 1 h. The WHOQOL-BREF scale and Happiness Scale (1) were used for data collection.
RESULT: The results showed a significant increase in the quality of life of participants in the treatment group with CRA compared with the control group with TMM. The findings also indicated that the individuals in the treatment group with CRA had improved levels of happiness compared with individuals with TMM.
DISCUSSION: The CRA is an effective and adaptable treatment approach that works well in combination with other treatment approaches. The proven efficacy, compatibility, and cost-effectiveness distinguish it from other treatment methods.
IMPLICATIONS: The CRA should be adapted, assessed, and evaluated further, especially in Pakistan, where there is a pressing need to adopt an effective treatment strategy for addiction problems.
Fulltext A comparison of responses to alcohol expectancy questionnaire (CEOA) of Indian and Malaysian medical students

Ganaraja B, Ramesh BM, Kotian MS

Indian J. Physiol. Pharmacol., 2010;54(3):265-70.
PMID: 21409864

Alcohol addiction is a social problem faced by every country worldwide. Young people are more at risk of this menace. In spite of a clear knowledge and message about the effects of alcohol on individual health and social fabric, it is hard to curb the overuse of this beverage. In the present study, we compared the outcome of a survey using Comprehensive effects of Alcohol (CEOA) in two private Medical institutions in two Asian countries, viz. KMC, Mangalore, India (n=180) and AIMST, Kedah, Malaysia (n=170). The study included both males and female students. The result suggested that the negative reinforcement responses were rated higher in both the study groups. But those who have tasted alcohol before had a higher rating that alcohol may cause positive reinforcement. Both groups of respondents showed similar trend suggesting that the alcohol expectancies are similar in Indian students and Malaysian students. From the results we could conclude that the responses of the two sample groups were comparable to each other. While the male respondents were inclined show higher affinity towards acceptance of alcohol females are very much less so. However, the respondents of both groups appeared to be well aware of the negative aspects of alcohol. Importantly previous exposure to alcohol intake dramatically changed the perception and showed increased inclination towards alcoholism. This study thus provides an important clue to the clinician, counselors and parents regarding the importance of guiding the young people about the alcoholism.
Fulltext Interfacial Compatibility Evaluation on the Fiber Treatment in the Typha Fiber Reinforced Epoxy Composites and Their Effect on the Chemical and Mechanical Properties

Rizal S, Ikramullah, Gopakumar DA, Thalib S, Huzni S, Abdul Khalil HPS

Polymers (Basel), 2018 Nov 28;10(12).
PMID: 30961241 DOI: 10.3390/polym10121316

Natural fiber composites have been widely used for various applications such as automotive components, aircraft components and sports equipment. Among the natural fibers Typha spp have gained considerable attention to replace synthetic fibers due to their unique nature. The untreated and alkali-treated fibers treated in different durations were dried under the sun for 4 h prior to the fabrication of Typha fiber reinforced epoxy composites. The chemical structure and crystallinity index of composites were examined via FT-IR and XRD respectively. The tensile, flexural and impact tests were conducted to investigate the effect of the alkali treated Typha fibers on the epoxy composite. From the microscopy analysis, it was observed that the fracture mechanism of the composite was due to the fiber and matrix debonding, fiber pull out from the matrix, and fiber damage. The tensile, flexural and impact strength of the Typha fiber reinforced epoxy composite were increased after 5% alkaline immersion compared to untreated Typha fiber composite. From these results, it can be concluded that the alkali treatment on Typha fiber could improve the interfacial compatibility between epoxy resin and Typha fiber, which resulted in the better mechanical properties and made the composite more hydrophobic. So far there is no comprehensive report about Typha fiber reinforcing epoxy composite, investigating the effect of the alkali treatment duration on the interfacial compatibility, and their effect on chemical and mechanical of Typha fiber reinforced composite, which plays a vital role to provide the overall mechanical performance to the composite.
Fulltext Understanding the psychology of mobile gambling: A behavioural synthesis

James RJE, O'Malley C, Tunney RJ

Br J Psychol, 2017 Aug;108(3):608-625.
PMID: 27753063 DOI: 10.1111/bjop.12226

This manuscript reviews the extant literature on key issues related to mobile gambling and considers whether the potential risks of harm emerging from this platform are driven by pre-existing comorbidities or by psychological processes unique to mobile gambling. We propose an account based on associative learning that suggests this form of gambling is likely to show distinctive features compared with other gambling technologies. Smartphones are a rapidly growing platform on which individuals can gamble using specifically designed applications, adapted websites or text messaging. This review considers how mobile phone use interacts with psychological processes relevant to gambling, the games users are likely to play on smartphones, and the interactions afforded by smartphones. Our interpretation of the evidence is that the schedules of reinforcement found in gambling interact with the ways in which people tend to use smartphones that may expedite the acquisition of maladaptive learned behaviours such as problem gambling. This account is consistent with existing theories and frameworks of problem gambling and has relevance to other forms of mobile phone use.
Medical sociology in the undergraduate medical curriculum in Malaysia

Chen PC

Br J Med Educ, 1972 Dec;6(4):323-4.
PMID: 4664477
Assessing physiological dependence and withdrawal potential of mitragynine using schedule-controlled behaviour in rats

Harun N, Johari IS, Mansor SM, Shoaib M

Psychopharmacology (Berl), 2020 Mar;237(3):855-867.
PMID: 31832720 DOI: 10.1007/s00213-019-05418-6

RATIONALE: Kratom is proposed to exhibit therapeutic potential as an opium substitute, but little is known about its dependence-producing profile, particularly of its main psychoactive compound, mitragynine (MG).
OBJECTIVES: This study examined the dependence-producing effects of MG using operant-scheduled behaviour in rats and investigated the potential therapeutic effect of MG by comparing effects to buprenorphine in morphine-dependent rats using the same schedule-controlled behavioural task.
METHODS: The effects of acutely administered MG and morphine were determined in rats trained to respond under fixed-ratio (FR) 10 schedule of food reinforcement. Next, the rats were administered MG and morphine twice daily for 14 consecutive days to determine if physiological dependence would develop by examining cessation of drug treatment and following antagonist-precipitated withdrawal. The study then examined the effects of MG substitution to suppress naloxone-precipitated morphine withdrawal effects on scheduled responding.
RESULTS: Acute doses of MG did not produce dose-related decreases on FR schedules of responding compared to morphine. Unlike morphine, MG-treated rats showed no suppression of response rates following cessation of MG treatment. However, withdrawal effects were evident for MG after precipitation by either naloxone or SR141716A (rimonabant), similar to morphine-treated rats. MG in higher doses (10 and 30 mg/kg) attenuated the naloxone-precipitated morphine withdrawal effects while smaller doses of buprenorphine (0.3 and 1.0 mg/kg) were necessary to alleviate these effects.
CONCLUSION: The findings suggest that MG does not induce physiological dependence but can alleviate the physical symptoms associated with morphine withdrawal which represent the desired characteristics of novel pharmacotherapeutic interventions for managing opioid use disorder (OUD).

Matched MeSH terms: Reinforcement (Psychology)*; Reinforcement Schedule*
Fulltext Noni (Morinda citrifolia L.) fruit extract attenuates the rewarding effect of heroin in conditioned place preference but not withdrawal in rodents

Narasingam M, Pandy V, Mohamed Z

Exp Anim, 2016 May 20;65(2):157-64.
PMID: 26744024 DOI: 10.1538/expanim.15-0088

The present study was designed to investigate the effect of a methanolic extract of Morinda citrifolia Linn. fruit (MMC) on the rewarding effect of heroin in the rat conditioned place preference (CPP) paradigm and naloxone-precipitated withdrawal in mice. In the first experiment, following a baseline preference test (preconditioning score), the rats were subjected to conditioning trials with five counterbalanced escalating doses of heroin versus saline followed by a preference test conducted under drug-free conditions (post-conditioning score) using the CPP test. Meanwhile, in the second experiment, withdrawal jumping was precipitated by naloxone administration after heroin dependence was induced by escalating doses for 6 days (3×/ day). The CPP test results revealed that acute administration of MMC (1, 3, and 5 g/kg body weight (bw), p.o.), 1 h prior to the CPP test on the 12th day significantly reversed the heroin-seeking behavior in a dose-dependent manner, which was similar to the results observed with a reference drug, methadone (3 mg/kg bw, p.o.). On the other hand, MMC (0.5, 1, and 3 g/kg bw, p.o.) did not attenuate the heroin withdrawal jumps precipitated by naloxone. These findings suggest that the mechanism by which MMC inhibits the rewarding effect of heroin is distinct from naloxone-precipitated heroin withdrawal.
Case Series

Vetrayan J, Othman S, Victor Paulraj SJ

J Atten Disord, 2017 01;21(2):168-179.
PMID: 23529885 DOI: 10.1177/1087054713479665

OBJECTIVE: To assess the effectiveness and feasibility of behavioral sleep intervention for medicated children with ADHD.
METHOD: Six medicated children (five boys, one girl; aged 6-12 years) with ADHD participated in a 4-week sleep intervention program. The main behavioral strategies used were Faded Bedtime With Response Cost (FBRC) and positive reinforcement. Within a case-series design, objective measure (Sleep Disturbance Scale for Children [SDSC]) and subjective measure (sleep diaries) were used to record changes in children's sleep.
RESULTS: For all six children, significant decrease was found in the severity of children's sleep problems (based on SDSC data). Bedtime resistance and mean sleep onset latency were reduced following the 4-week intervention program according to sleep diaries data. Gains were generally maintained at the follow-up. Parents perceived the intervention as being helpful.
CONCLUSION: Based on the initial data, this intervention shows promise as an effective and feasible treatment.

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