Group Size Research Articles

Presence of abnormal otoliths in hallucinogenic fish and their comparison with normal otoliths using light and scanning electron digital imaging.

The otolith organs located in the inner ear of the fish are responsible for vital activities such as balance and hearing. Abnormalities in these organs can adversely affect the vital activities of the fish species. The main purpose of the study is to analyze the abnormalities in the otoliths of Sarpa salpa, known as the hallucinogenic fish. For that, 372 individuals of S. salpa are collected from the North Aegean Sea. As a result of the abnormality analyses in S. salpa otoliths, anomalies were detected such as various prominence structures on the surface of the otolith caused by accumulation and a more transparent appearance due to the different crystal structures in some parts of the otolith. These abnormalities were found in the left and/or right otoliths of male and female individuals in different total lengths. The percentage of individuals with abnormal otoliths of S. salpa is calculated as 52.42%. It was determined that there are statistical differences between the left and right otolith measurements of male and female individuals with abnormal and normal otoliths(p < 0.05). There is no relationship between the percentage of individuals showing abnormality and total length and sex. The current study presents for the first time abnormal otolith information on left and right otoliths in male and female S. salpa. It is thought that abnormalities in hallucinogenic fish otoliths could be related to genetic predisposition as well as stress due to nutritional preference, pollutants, and environmental factors. RESEARCH HIGHLIGHTS: The presence of abnormalities in the otoliths of Sarpa salpa, a hallucinogenic fish, was revealed for the first time. Abnormalities in the otoliths of S. salpa were identified, such as the presence of various prominence structures on the otolith's surface, loss of parts as well as a more transparent appearance in the outlines or surface of the otolith. Normal and abnormal otoliths of female and male hallucinogenic fish from different size groups were examined using light and scanning electron microscopy. Abnormality detected in the otoliths of hallucinogenic fish is not related to the gender and size of the fish.

Determination of body length regression formulas for the golden grey mullet (Chelon auratus, Risso 1810) based on otoliths found in the feces of the Caspian Seal (Pusa caspica Gmelin, 1788)

The Caspian Seal, the sole mammal endemic to the Caspian Sea, is listed in the IUCN Red List as a species facing the threat of extinction, a status similarly recognized and/or assigned in all countries in the Caspian region.The study of seal nutrition using caprological methods is of great interest for understanding animal adaptation to deteriorating habitat conditions and assessing the adequacy of their food base in the sea. This method involves analyzing the contents of feces from ichthyophages to detect undigested fish otoliths.The results of studying the seal's diet during periods of haulout on breeding grounds showed that the frequency of occurrence of Chelon auratus otoliths ranged from 2-3% to 27.7% of all fish otoliths detected in feces.This study aims to assess changes in Chelon auratus otoliths as they pass through seals' gastrointestinal tracts and estimate formulas for recovering the linear dimensions of fish consumed by these seals.The research indicates that otolith growth slows with fish growth but does not cease entirely. Allometry is evident in the different ratios of otolith length and width to fish length in various size groups and the change in otolith shape as fish grow.To recover the body length of fish consumed by seals based on otoliths found in their feces, applying inverse calculation formulas obtained when studying the relationship between otolith growth and fish body growth using collection material obtained directly from fish is possible.Further research should focus on refining the recovery formula for the length of large fish by dividing the length into several segments, each described by separate formulas describing the relationship between fish body length and otolith length and width growth.

Botulinum toxin treatment of refractory vaginismus: a prospective study.

Vaginismus is a common sexual dysfunction. A few studies have indicated that botulinum neurotoxin type A (BoNTA) can help treat refractory vaginismus by alleviating muscle tension. However, such studies did not use standardized methodology and BoNTA dosage. The aim is to evaluate the efficacy of intravaginal BoNTA injection in treating refractory vaginismus. Also, we intended to assess the effectiveness and safety of modest doses, that is, 100 to 200 IU of submucosal BoNTA injections. A prospective study was conducted in an outpatient surgical center over 18 months. Twenty patients aged 29 to 49 years (mean, 30.9 years) with refractory vaginismus were enrolled. All patients had been sexually inactive at the time of treatment. All participants had received various treatments such as psychotherapy, vaginal dilatator therapy, muscle relaxants, and lubricants with no relief. A dose of 100 to 200 IU of BoNTA was injected submucosally in the lateral sides of the bulbospongiosus, pubococcygeus, and puborectalis muscle areas. The patients were followed over 4 months posttreatment. Nineteen patients (95%) achieved satisfactory intercourse by the end of the 4-month follow-up period. A repeat BoNTA injection was not required as there were no recurrences. None of the participants reported adverse effects. A small sample size and lack of a control group. Injecting submucosally modest BoNTA doses is an effective and safe treatment for refractory vaginismus. When conventional therapies fail, BoNTA can be used to lessen muscle contraction, alleviate pain, and facilitate dilator treatments. Our standardized protocol, which involves a careful submucosal injection technique, can minimize risks and make the procedure easy to perform for daily practice.

Burnout in Australian sport and exercise physicians and registrars: A cross-sectional study

ObjectivesTo determine the prevalence and factors associated with the risk of burnout among sport and exercise physicians and registrars in Australia. DesignCross-Sectional Study. MethodAustralian based sport and exercise physicians and registrars of the Australasian college of sport and exercise physicians were invited to complete a survey. Demographic data and response to a questionnaire utilising the Maslach Burnout Inventory (MBI) tool were collected. Descriptive analysis was conducted to assess the prevalence of burnout. Multivariable logistic regression models were used to determine factors associated with the risk of burnout whilst adjusting for covariates. Results25 registrars (25/52 ​= ​48%) and 31 physicians (31/172 ​= ​18%) completed the survey. The risk of overall burnout in all three MBI parameters or in at least one parameter was 25% and 34%, respectively. Findings of the primary analysis showed that higher working hours (AOR 50.59; 95% CI 1.81–141.33; p ​= ​0.021) and higher level of job dissatisfaction (AOR 262.68; 95% CI 4.98–13857.50; p ​= ​0.006) were associated with increased odds of burnout. ConclusionsBurnout poses a significant risk to sport and exercise physicians and registrars in Australia. The small size of this specialty group and unique nature of their work requires specific interventions to reduce risks of burnout.

Essential Structural Profile of Novel Adenosine Derivatives as Antiplatelet Aggregation Inhibitors based on 3D-QSAR Analysis

Aims: In this research, 3D-QSAR evaluation on a set of fresh purinoid compounds that we produced was conducted. This analysis aims to illustrate the correlation between the structure of purine and its ability to prevent platelet aggregation. Our findings could pave the way to discovering novel antithrombotic medications. Background: The incidence of cardiovascular disease triggered by the clumping of platelets poses a significant danger to human health. Purine derivatives are important molecules with antiplatelet aggregation activity. Objective: The objectives of this research are to establish the correlation between the structure of purine and its ability to prevent platelet aggregation. Such a correlation could aid in the development of innovative antithrombotic medications. Methods: In this study, 3D-QSAR investigation on a collection of 75 new purine derivatives, which we synthesized, was conducted, utilizing Comparative molecular field analysis (CoMFA) and comparative molecular similarity indices analysis (CoMSIA). Results: Significant correlation coefficients (CoMFA, q2= 0.843, r2= 0.930, F value= 266.755, SEE= 0.165; CoMSIA, q2= 0.869, r2= 0.918, F value= 222.571, SEE= 0.179) were obtained, and assessed the model's predictive capabilities by validating it with the test set. Conclusion: Our findings indicate that the introduction of an appropriately sized structure at position 2 of the compound yields significant benefits. Conversely, the attachment of an excessively large group is detrimental. Direct attachment of a bulky substituent at C-6 of the compound is not feasible, and its activity increases when the structure with low electron cloud density is added. Moreover, the presence of a voluminous functional group at the 5' position of the compound is advantageous, and its activity will be further increased by the presence of hydrogen bond receptors in this region. These discoveries furnish significant comprehension for the formation of innovative structures with heightened efficacy.

Analysis of Naja kaouthia snake venom composition and in-vitro enzymatic activities of 29 specimens in captivity: Highlighting the importance of individual variation in venom pool production

Naja kaouthia is a medically important snake, widely distributed throughout Southeast Asia, with a diverse venom composition. N. kaouthia venom is subject to significant intraspecific variation, caused by several factors, such as the wide geographic distribution of the species, sexual and ontogenetic factors. However, individual variation is a factor that has only been studied with small sample size groups and/or with pooled samples. With this in mind, this study evaluates the composition and in-vitro enzymatic activities of 29 individual venom samples from specimens born in captivity, with a similar genetic background caused by inbreeding, using SDS-PAGE under reducing conditions, RP-HPLC profiles and enzymatic activities of PLA2, LAAO and proteolytic activity over azocasein. Even in this scenario, we were able to observe significant variations in abundance and activity of PLA2. Individual variations in LAAO activity, as well as a sexual dimorphism in which males present a significantly higher LAAO activity than females were observed. Phosphodiasterase and CRiSP abundance were also found and considered to have multiple effects in the clinical manifestations of envenomation by presenting synergistic effects with other proteins from N. kaouthia venom. The RP-HPLC profiles were better at detecting compositional differences than SDS-PAGE profiles and better correlated with enzymatic activities, being a better technique to screen variation profiles and reinforcing the importance of individual venom analysis prior to pooling.

Enhancing Gout Diagnosis with Deep Learning in Dual-energy Computed Tomography: A Retrospective Analysis of Crystal and Artifact Differentiation.

To evaluate whether the application of deep learning (DL) could achieve high diagnostic accuracy in differentiating between green colour coding, indicative of tophi, and clumpy artifacts observed in dual-energy computed tomography (DECT) scans. A comprehensive analysis of 18 704 regions of interest (ROIs) extracted from green foci in DECT scans obtained from 47 patients with gout and 27 gout-free controls was performed. The ROIs were categorized into three size groups: small, medium, and large. Convolutional neural network (CNN) analysis on a per-lesion basis and support vector machine (SVM) analysis on a per-patient basis were performed. The area under the receiver operating characteristic curve, sensitivity, specificity, positive predictive value, and negative predictive value of the models were compared. For small ROIs, the sensitivity and specificity of the CNN model were 81.5% and 96.1%, respectively; for medium ROIs, 82.7% and 96.1%, respectively; for large ROIs, 91.8% and 86.9%, respectively. Additionally, the DL algorithm exhibited accuracies of 88.5%, 88.6%, and 91.0% for small, medium, and large ROIs, respectively. In the per-patient analysis, the SVM approach demonstrated a sensitivity of 87.2%, a specificity of 100%, and an accuracy of 91.8% in distinguishing between patients with gout and gout-free controls. Our study demonstrates the effectiveness of the DL algorithm in differentiating between green colour coding indicative of crystal deposition and clumpy artifacts in DECT scans. With high sensitivity, specificity, and accuracy, the utilization of DL in DECT for diagnosing gout enables precise lesion classification, facilitating early-stage diagnosis and promoting timely intervention approaches.

Polymodern Economics

Polymodernity could be defined as cultural infrastructure. It describes the cultural evolution of the human species in four cultural codes and integrates them: indigenous, traditional, modern, and postmodern. These four cultural codes very much relate to group sizes, and they represent four different kinds of social interaction, cooperation, economy, moral values, media, and much more. In this article, I describe the economy as a structure of five integrated layers. The first is nature itself; the other four are economic models with different goals, dynamics, rules, measurements, criteria for success, and opportunities for sustainability and thriving. All five layers are present in thriving economies. This article presents a suggestion for a macro-economic model that can deliberately balance them.

The effect of group size and laying month on the quality, IgG, and corticosterone levels of goose eggs

Abstract. Environmental stress is known to negatively affect poultry health, production, and egg quality. Our study aimed to evaluate the effects of two different group sizes and the laying month on egg quality characteristics as well as the effect of group size on corticosterone and IgG levels in goose eggs. The research was conducted on a semi-free-range goose breeder farm in Hajdú–Bihar county, Hungary. The eggs included in the analysis were produced by 4-year-old geese of the Grimaud breed. Two group sizes were constructed; the large group contained 850 birds; and there were three small groups, each containing 50 geese as replicates. The effect of the laying month and group size on egg quality parameters and the effect of group size on egg IgG and corticosterone contents were investigated. Eggs laid in January at the peak of production and at the end of February (low-production period) were involved in the study. Regarding the effect of months, we noticed a decrease in egg width (from 6.12 to 5.98 cm), shell thickness (from 0.76 to 0.61 mm at the blunt end, from 0.69 to 0.61 mm at the equator, and from 0.65 to 0.56 mm at the pointed end), shell weight (from 19.56 to 18.19 g), yolk weight (from 69.05 to 62.35 g), yolk ratio (from 36.45 % to 34.43 %), yolk diameter (from 7.09 to 6.59 cm), and yolk colour with fan (from 12.58 to 11.83) and b∗ (from 54.57 to 49.91) (P ≤ 0.05). The albumen ratio and yolk pH increased from 53.24 % to 55.51 % and from 6.18 to 6.29 from January to February, respectively. Regarding group size, the albumen pH (8.77 vs. 8.67), IgG (4955 vs. 3823 ng mL−1), and corticosterone (187.26 vs. 76.24 ng mL−1) levels were higher in the small groups (P ≤ 0.05).

Higher eigenvector centrality in grooming network is linked to better inhibitory control task performance but not other cognitive tasks in free-ranging Japanese macaques.

The Social Intelligence Hypothesis predicts that complex social environments promote higher cognitive capacities. This hypothesis is often tested by comparing species or conspecific groups with varying group sizes or social structures. However, individual social environments differ not only among species or groups but also within the same group. We examined the relationship between social centrality and cognitive ability in wild Japanese macaques (Macaca fuscata). We created a grooming network using data from 196 adult macaques and calculated social centrality for each individual. We then tested the macaques with a cognitive test battery to assess their abilities in social, physical, and inhibitory control domains. Our findings revealed that social centrality was uniquely associated with inhibitory control performance, particularly in the behavioral inhibition task, but not with other cognitive domains. This suggests that inhibitory control, a key component of executive functions, plays a pivotal role in the social lives of wild Japanese macaques.

Response of Irritable Bowel Syndrome to Abdominal Fat Reduction

Objectives: The study aimed to evaluate the response of Irritable Bowel Syndrome (IBS) among patients having central obesity to reducing abdominal fat using Focused Ultrasound (cavitation) in addition with aerobic exercise as well as a low calorie, low-FODMAPs diet. Methods: A total of 60 individuals, between the ages of 20 and 45, who were diagnosed with both irritable bowel syndrome (IBS) as well as abdominal obesity, having a body mass index (BMI) ranging from 30 to 39.9 kg/m², were divided into two groups of similar size by a random assignment process. Group A were given focused ultrasound cavitation accompanied by moderate aerobic exercise and a low calorie, low-FODMAPs diet over a period of three months, whereas Group B (control group) were given moderate aerobic exercise and a low calorie, low-FODMAPs diet only. Assessments of total body fat, abdominal fat, severity of IBS, as well as quality of life related to IBS were conducted prior to and after the study period. Results: Overall body fat mass, abdominal fat mass, IBS severity, and IBS quality of life were all significantly improved in both groups. All evaluated variables showed a highly significant improvement in favor of the study group when comparing the two groups. Conclusion: Focused Ultrasound (cavitation) in addition with aerobic exercise as well as a low calorie, low-FODMAPs diet cause more improvement of irritable bowel syndrome symptoms and quality of life.

A Comparative Analysis of Drone and Boat Monitoring for the Endangered Bolivian River Dolphin

Accurate population monitoring is essential for effective wildlife conservation. This study compares the effectiveness of drone-based vs traditional boat-based methods for assessing an endangered Bolivian river dolphin (Inia geoffrensis boliviensis; BRD) population in Bolivia. Data were collected using high-resolution video recorded with a DJI Mavic 2 zoom drone and standardized methodologies for boat surveys. Two mixed-effects linear models incorporating Poisson and negative binomial error structures were used to compare counts obtained from drone- and boat-based surveys. Results show that drone-based surveys detected 1.15% more individuals on average than boat-based surveys. Drone counts were higher at sites with larger group sizes, leading to congruent estimates. The aerial perspective that drones offer lets researchers overcome potential challenges from boat-based surveys—for example, difficulties related to confirming individual IDs because of limited visibility due to sun glare. Transitioning from boat- to drone-based surveys offers advantages such as reduced disturbance from placement closer to the animals and improved detection rates. Ethical considerations and responsible flight practices are crucial. Standardizing methodologies and prioritizing ethical research factors are key for successful implementation. Drone-based surveys offer a promising approach to enhance wildlife monitoring and conservation practices. This study is the first of this kind for Bolivia, a national natural heritage site, and contributes to the conservation and knowledge of the BRD.

The upsides to working with a lap book as a study aid

This research assesses the utility of lap books as a didactic aid in teaching crowded classrooms with specific reference to the participation level and academic achievement. The study was carried out over three terms of high school English classes in a school in Quito, Ecuador; the assessment of results was done both through oral lessons and by end-term written tests. Results also reveal that lap books foster better performance in tests in terms of an increased number of high scores and reduced lower scores in subsequent years. Combining constructivist learning and differentiation as a teaching approach, lap books enhance student participation as well as foster individual learning styles that make the content more easily understandable and retained. The change that was observed across terms indicates improved overall performance, and the existence of lap books facilitated equality in terms of high grades. Consequently, based on such findings made in this study, it is recommended that the development and use of lap books can be adopted as a more conceptually appealing approach for enhancing students’ learning in situations where a more direct form of one student/teacher ratio, interaction is due to large group sizes.

Characterization of glomalin proteins in soil: A potential indicator of erosion intensity

Abstract In this study, in a pioneering effort, glomalin proteins were extracted and geochemically characterized from soil in Serbia. Standard chemical (dry combustion, Walkley-Black) and spectroscopic methods (fourier transform infrared spectroscopy (FTIR), dynamic light scattering (DLS), scanning electron microscope (SEM)) were used to gain insight into the glomalin proteins. Samples from the City of Novi Sad (Serbia) were used for characterization and comparison. The soil contained an average of 17 mg/g of glomalin, representing ≈21% of the soil organic matter. DLS zeta potential analysis and the FTIR spectra reveal two significant differences before and after glomalin extraction, indicating a relationship between sand fractions and organic matter that affects particle aggregation and erosion potential. A comparison of SEM images and DLS results reveals that the glomalin extract consists of two particle size groups (0.08–1 and 6 µm), suggesting that the extraction process isolates only a smaller fraction of proteins and less tightly bound particles, indicating that soil aggregation is influenced by both mineralogy and the characteristics of organic matter. Hence, our research raises important questions about the role of glomalin in mitigating soil degradation processes, particularly soil erosion. Our study will enhance the overall understanding of glomalin, inspire future research, and prove beneficial for the sustainable restoration of degraded lands.

Exploring the dynamics of ultrasound training in medical education: current trends, debates, and approaches to didactics and hands-on learning.

Medical education, especially in ultrasound training, is undergoing significant changes. This study examines practical issues in ultrasound medical education, emphasizing state-of-the-art teaching methods, their effectiveness, and implementation challenges. The study analyzed advancements in ultrasound education, including randomized controlled trials comparing peer-to-peer teaching with traditional faculty-led instruction. It evaluated the effectiveness of collaborative small-group training and group size impact in simulation-based training. The study also assessed practical training components outlined in the WFUMB Position Paper Part II. Findings indicate that peer-to-peer and collaborative small-group training are effective and cost-efficient. Group size did not significantly affect training outcomes. Key practical training elements, including early hands-on sessions and exposure to various equipment, substantially improved learning outcomes. Simulation tools like virtual reality (VR), augmented reality (AR), and phantoms were crucial for teaching standardized procedures and rare pathologies. Challenges identified include developing robust image acquisition skills, scarcity of qualified student tutors, and the need for reliable ultrasound skill assessment methods. Integrating peer-to-peer teaching and advanced simulation technologies significantly advances ultrasound medical education. These methods enhance cognitive and psychomotor skills but also present challenges such as ensuring quality education and developing effective assessment methods. Future research should compare different simulation tools and establish objective ultrasound proficiency assessment criteria. Continual method evaluation and improvement are essential for effective and standardized ultrasound training, ultimately enhancing patient care and clinical outcomes.

Dietary Effect of Withania somnifera (Ashwagandha) Root Powder on Growth and Blood Parameters of Cyprinus carpio (Common Carp)

Aims: The present study evaluated the effect of different levels of Withania somnifera root powder in fish formulated diets on the growth performance of economically important freshwater fish species in Asia Cyprinus carpio and compare the hematological changes occurred in fishes fed with control feed and herbal formulated diet. Study Design: The experiment was planned with the size group of 30.0±1.0g. Fish of the respective size group of Cyprinus carpio were subjected to different herbal formulated diets at a concentration 0%, 0.5%, 1.0%, 1.5%, 2.0% of Withania somnifera root powder extract through their diet, while the control group received a standard diet without any supplementation. Duration of Study: The study was conducted over a period of 4 weeks. Methodology: During which growth parameters such as Average Daily Growth, Specific Growth Rate and Absolute Growth Rate were monitored at regular (10 days) intervals. The blood samples were collected at 4th week from each group to assess hematological parameters including Red Blood Cell count, White Blood Cell count, Hemoglobin, Total Cholesterol and Total serum protein levels. The overall results revealed that the inclusion of Withania somnifera extract in the diet of Cyprinus carpio significantly influenced both growth and blood parameters. Results: Fish exposed to Withania somnifera extract exhibited enhanced growth performance compared to the control group, with increased Average Daily Growth, Specific Growth Rate and Absolute Growth Rate. Moreover, hematological analysis revealed positive effects on the blood parameters of treated fish, including improvements in Red Blood Cell count, White Blood Cell count, Hemoglobin, Total Cholesterol and Total serum protein levels. Conclusion: The overall results revealed that the inclusion of Withania somnifera extract in the diet of Cyprinus carpio significantly influenced both growth and blood parameters.

Empowering minorities and everyone in participatory budgeting: an agent-based modelling perspective.

Currently, there are increasing attempts to better involve citizens in political decision processes. A successful approach in that regard has been participatory budgeting (PB), which allows citizens to propose projects and then decide how to distribute a given budget over them. Meanwhile, the literature on collective intelligence (CI) has also shown the ability of groups to solve complex problems. Thus, by combining CI and PB, it should be possible for citizens to identify problems and create their own solutions. In this article, we study this possibility by using agent-based models. Specifically, we first show that a system combining CI and PB produces solutions that strongly penalize minorities if the solution quality depends on group size. Then, we introduce an approach that can overcome this issue. Indeed, by using a common knowledge base for the storage of partial solutions, the quality of solutions of minorities can benefit from the work of the majority, thereby promoting fairness. Interestingly, this approach also benefits majorities, as the quality of their solutions is further improved by the work of the minorities, thus reaching better solutions for everyone. This stresses the potential and importance of an open innovation approach, which is committed to information sharing.This article is part of the theme issue 'Co-creating the future: participatory cities and digital governance'.

Rural Tourist Attractions Recommendation Model Based on Multi-Feature Fusion Graph Neural Networks

With the rapid growth of the rural tourism industry, traditional tourism recommendation technologies can no longer meet the necessary requirements. To address the issue of rural tourist attraction recommendations, a rural tourist attraction recommendation model is constructed based on a multi-feature fusion graph neural network. First, construct a feature map based on the relationship between tourists’ preferences and tourist attractions, and incorporate the attention mechanism to enhance the model’s learning capabilities. Second, utilize a two-part graph model to extract positive and negative preference features of tourists, and a conversation graph model to extract tourists’ transfer preference features. Finally, various features are utilized to generate suggested content by computing scores for tourists’ travel preferences. To address the problem of recommending tourist groups, suitable features for random group matching are collected and the cosine function is employed to identify users with similar random group features. Finally, the multi-features are merged, and the tourists’ interest preferences are scored to arrive at content recommendations. In the experiment on individualized attraction recommendations, data from the Chengdu area were used to test the proposed model. The accuracy of the model’s recommendations was 0.822 for five recommendations which outperformed the other models. In the experiment for group-based attraction recommendations, this experiment tested the Chengdu dataset. The proposed model achieved the highest accuracy of 0.972 when the group size was 70, outperforming the other two models. Additionally, with regards to different numbers of recommendations, the proposed model’s accuracy was 0.5241, which was the best performance among the three models when the number of recommendations was set to five. The proposed recommendation model performs optimally in suggesting tourist attractions and meets the needs of rural tourism. The research content provides crucial technical references for tourist traveling and rural tourism development.

Decisions on group buying option in a duopoly environment

Group buying has emerged as a distinctive strategy in today's product and service markets, offering low-priced products to a large number of customers. As many sellers now offer both group and individual purchasing options, this pricing model benefits both sellers and buyers, with sellers reducing prices to drive higher sales volume. In this study, we investigate the competition between two retailers selling substitutable products in the same market through both group and individual purchasing mechanisms. The profit function of duopoly retailers is represented, using a game theoretic approach to evaluate the conditions under which group buying is offered. Additionally, we address the challenge of determining individual and group prices, as well as the optimal group size. The numerical analysis reveals that in collectivist-dominated markets, where group buying is easily viable, offering group prices may not be beneficial for retailers. While, in individualist-dominant markets, retailers tend to provide both group and individual prices.

A context-based model of collaborative inhibition during memory search.

Contrary to common intuition, a group of people recalling information together remembers less than the same number of individuals recalling alone (i.e., the collaborative inhibition effect). To understand this effect in a free recall task, we build a computational model of collaborative recall in groups, extended from the Context Maintenance and Retrieval (CMR) model, which captures how individuals recall information alone. We propose that in collaborative recall, one not only uses their previous recall as an internal retrieval cue, but one also listens to someone else's recall and uses it as an external retrieval cue. Attending to this cue updates the listener's context to be more similar to the context of someone else's recall. Over an existing dataset of individual and collaborative recall in small and large groups, we show that our model successfully captures the difference in memory performance between individual recall and collaborative recall across different group sizes from 2 to 16, as well as additional recall patterns such as recency effects and semantic clustering effects. Our model further shows that collaborating individuals reach similar areas in the context space, whereby their contexts converge more than the contexts of individuals recalling alone. This convergence constrains their ability to search memories effectively and is negatively associated with recall performance. We discuss the contributions of our modeling results in relation to previous accounts of the collaborative inhibition effect.