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The extensive usage of organophosphate pesticides (OPs) has posed severe harm to human health and environmental system, but achieving highly effective and on-site detection is still a great challenge. In this work, a novel nanozyme Nb2CTx MXene/bimetallic PdPt (Nb2CTx@PdPt) was synthesized firstly through a simple self-reduction method, and the results show that the as-prepared Nb2CTx@PdPt nanozyme exhibits outstanding peroxidase-like activity. Interestingly, the nanozyme activity of Nb2CTx@PdPt is restrained remarkably in the presence of acetylcholine chloride and acetylcholinesterase while it can be restored through the addition of OPs (selecting glyphosate as a model). Based on this phenomenon, a sensitive colorimetric assay coupled with hydrogel and smartphone for OPs was then constructed. After optimizing various conditions, the designed sensing platform can achieve stable, rapid, and sensitive on-site detection for OPs, showing superior sensing performances: a wide linearity of 1.0 ng mL−1–1.0 µg mL−1 and low detection limit of 0.419 ng mL−1. [ABSTRACT FROM AUTHOR]

Polymer-based materials are of high potential for application as active materials in contemporary electronic gadgets. The functionality of such materials is highly dependent on their oxidation state and requires fine control during their synthesis. Owing to that, we have designed a cost-effective, simple, portable, system for calibration and the detection of the optical and electrical properties of polyaniline loaded on a paper substrate using a smartphone-based colorimetric sensor. The vapor phase polymerization technique was adopted for preparing polyaniline. Colorimetric measurements of polyaniline-loaded papers were achieved by estimating the hue, saturation and value (HSV) color parameter values using an open-source smartphone application called 'Color Grab (Color Detection)' during synthesis at different time intervals. The proposed sensor relies on the principle of Beer-Lambert law. The rear camera of the smartphone acts as a sensor and captures the light signal from the samples and provides information to the colorimetric app. The colorimetric results showed a promising correlation between the color parameter values with their electrical properties. The optical absorbance results of all polyaniline-loaded papers are also in accordance with the H parameter values. The proposed sensor can be used as a portable smartphone-based point-of-care testing kit to bring in-situ control during synthesis. Highlights * Conducting polymer on flexible cellulose substrate. * Smartphone-based visual colorimetric sensor. * Biodegradable and environment-friendly electronic material. * Variation of electrical properties in terms of hue values. * Cheap, portable sensor for point-of-care testing. KEYWORDS charge transport, colorimetry, conducting polymer, point-of-care testing, portable, smartphone application, 1 | INTRODUCTION The evolution of polymers is now an emerging topic in the field of materials and nanoscience. Different polymer materials are evolving for application in electronic and optoelectronic [...]

Response disequilibrium theory, an extension of the response deprivation hypothesis, proposes that behavior-change is due to disruptions in an organism's baseline levels of responding. This theory challenges the notion of distinct stimuli as reinforcers or punishers and instead emphasizes the role of instrumental and contingent activities. The present study aimed to test the predictions of response disequilibrium theory by replicating Heth and Warren's, Animal Learning & Behavior, 6, 294-300, (1978) experiment using a modernized apparatus. Sixteen undergraduate psychology students participated in the experiment, which included a familiarization period, baseline periods, and a contingency period. During the contingency period, the instrumental activity was the activation of a video that resulted in a deficit or excess of audio relative to baseline. According to response disequilibrium theory, a deficit will produce a reinforcement effect whereas an excess will produce a punishment effect. The results supported the predictions of response disequilibrium theory, as instrumental video activity increased for participants in the deficit condition and decreased for participants in the excess condition. In addition, the study revealed a strong correlation between the size of disequilibrium and the magnitude of behavior change. These findings further support the use of disequilibrium models to a priori identify effective contingency arrangements in both research and practice. Informal applications of the Premack principle may be supplanted with the precision of a formal model of reinforcement and punishment in response disequilibrium theory. Keywords Disequilibrium model * Reinforcement * Response disequilibrium theory * Response deprivation hypothesis * Premack principle * Punishment, The disequilibrium theory of reinforcement and punishment is an extension of Timberlake and Allison's (1974) response deprivation hypothesis. Timberlake (1980) referred to this approach as a Molar Equilibrium Theory of [...]

Background: Mobile App Rating Scale (MARS) is a well-known ranking tool used to evaluate the quality of mobile health applications. In this study, we translated MARS into Persian and evaluated the quality of COVID-19-related applications in Iran. Materials and Methods: This study was conducted in two stages. First, MARS tool was translated into Persian, then back-translated into English, and finally, the corrected version was developed. In the second stage, applications for COVID-19 were searched in Cafe Bazaar, Sib App, Sib Irani and Myket applica-tion stores between July 2023 and December 2023. We used the translated version of the MARS to eval-uate the quality of the identified applications and rank them accordingly. Results: After developing the final version of the MARS, we measured its reliability using Cronbach's al-pha coefficient, which ranged from 0.79 to 0.81. Twelve applications were included in the study. Among the reviewed applications, the highest score was related to Corona Virus, with a mean of 4.20. Also, 33.8% of the applications were ranked as good, 50% as acceptable, and 66.41% as poor. Conclusion: The present study showed that the applications designed for COVID-19 are generally not of acceptable quality. A low score in the dimension of engagement suggests that the designers have paid less attention to the quality of the information contained in and the attractiveness of the applications.

FEATURES / COVER STORY [Innovation] The Three Traps That Stymie Reinvention Organizational identity, architecture, and collaboration can be either assets or liabilities to pursuing growth in new sectors. By Ryan [...]

The research dilemma was identified in considering the reality of the Saudi society’s uses of WhatsApp, patterns of its use, controls, and imitations. Similarly, the research was focused on trying to figure out the role which the application plays in obtaining the news and discussing the issues of concern to the community through the features provided by WhatsApp. Consequently, the importance of the research comes from the significance of the role which WhatsApp plays in transferring news and information. The study depended on the survey method, and it was applied on an improbable sample with the snowball system of 629 respondents. The study found, in its most important results, that the majority of the study sample (98.1 %) use WhatsApp. They agreed on the existence of many advantages such as the ability of sending and receiving various media and they can return to any of the conversations and media in anytime. On the other hand, they also agreed that one of the disadvantages is the easiness of penetration, which constitutes a breach and infringement of individual privacy besides the disadvantage of showing their daily lives on the status in a permanent way. The study showed that the majority of the sample (97.4%) were participating in WhatsApp groups and about (39.7%) of the sample participated in five to ten groups. Indeed, most of the groups that they join and obtain their interests are divided between the family, friends, and work. The results also showed the occurrence of a number of controls in re-publishing messages to ensure the information validity and containing worthy and useful news. One of the hypotheses revealed moderate correlation between the control variables in re-publishing messages of Whatsapp groups of friends and the rest of variables (the extent of interest in following and joining groups and participating in discussion, texts, and visual and readable materials). Through testing the hypotheses, the researcher concluded that the control variable and republishing determinants which was identified by the sample respondents can play a greater role in different usage patterns compared to their variable perceptions of the research sample’s members about advantages and disadvantages of Whatsapp [ABSTRACT FROM AUTHOR]