The influence of psychological needs and motivation on game cheating: insights from self-determination theory.

Introduction: Game cheating (i.e., behavior of violating rules in games by using unregulated Software or assistive devices to gain advantage) poses a fatal problem as it destroys fair competition systems and negatively impacts the game ecosystem. Game cheating is reported to be common in competitive online games because they stimulate strongly a user's motivation and psychological needs. However, there is still in lack of academic research which focused on the issue from the psycho-social perspective. Methods: This study investigated the relationships between basic psychological needs (i.e., autonomy, competence, and relatedness) and motivation (i.e., intrinsic and extrinsic) based on self-determination theory, and examined their effects on the degree of game cheating with survey data of 322 gamers in a competitive online gaming community. Results: The results showed the opposite associations between the two forms of motivation (intrinsic and extrinsic) and game cheating. On one hand, extrinsic motivation decreased by autonomy enhanced the degree of game cheating. On the other hand, intrinsic motivation increased by both autonomy and relatedness finally abated game cheating. Competence did not influence any form of motivation. The results indicated that people motivated by interest or enjoyment (i.e., intrinsic motivation) of the game tend to view game cheating negatively while those motivated by game victory and rewards are likely to have positive attitudes toward game cheating. Increasing the degree of user autonomy and social relations in the game could decrease game cheating through the enhancement of intrinsic motivation. Discussion: Digital game cheating is a crucial problem threatening the spread of game culture and the growth of the eSports industry. The findings of this study reveal the influence of psychological needs and intrinsic motivation related to 'game cheating,' providing valuable guidelines in educational and policy aspects.

Why Do Some Users Become Enticed to Cheating in Competitive Online Games? An Empirical Study of Cheating Focused on Competitive Motivation, Self-Esteem, and Aggression.

Cheating, the act of winning in a competition based on unfair advantages over one's opponents, often occurs in online games (e.g., illegal money exchange, account hacking, and exploiting a bug). With the recent flourishing of competitive tournament games online, such as League of Legends (LoL) and Overwatch, cheating has emerged as a serious problem since it not only promotes the de-socialization of gamers but also adversely affects game brands. However, there has little research on this issue in studies on competitive online games. Focused on three psychological factors (i.e., competitive motivation, self-esteem, and aggression), which has been reported to be primarily related to cheating in sports, this paper presents a study that empirically examined the associations between the factors and cheating in competitive online game environments. From survey data of 329 LoL gamers in South Korea, a structural equation model was analyzed. The results showed that gamers with a high degree of competitive motivation are more inclined to cheat in the game. Aggression increased cheating behavior and had a significant relationship with competitive motivation. Self-esteem decreased the degree of cheating but did not affect competitive motivation. Notably, gaming time negatively influenced cheating. The practical implications of these study results were discussed.

Exploring the Mechanism of Pathological Gaming in Adolescents: Focused on the Mediation Paths and Latent Group Comparison.

Pathological gaming among adolescents has been reported to hamper the achievement of a balanced life and to threaten the development of social competencies. Despite the increasing social concerns on the adolescent users, however, the mechanism of gaming behavior of adolescents has not been sufficiently examined. This study explored the mechanism of pathological gaming among adolescents from 3-year longitudinal data of 778 Korean adolescent gamers, by analyzing the effects of negative affects (i.e., anxiety, loneliness, and academic stress) on the degree of pathological gaming through the mediation variables (i.e., aggression and self-control) based on the stimulus-organism-response (S-O-R) framework. Latent class analysis (LCA) was used to uncover potential risk groups, and through partial least squares-structural equation modeling (PLS-SEM) analysis, the mediation pathways to pathological gaming were compared between the risk group and the non-risk group. The results highlighted the key role of academic stress on the degree of pathological gaming. In the entire group, academic stress primarily increased pathological gaming through self-control. The mediation path of self-control was the most influential result in the risk group. Aggression was the key mediator between loneliness and pathological gaming in the non-risk group. The theoretical and practical implications of the results were discussed.

Pathological Gaming in Young Adolescents: A Longitudinal Study Focused on Academic Stress and Self-Control in South Korea.

With the increase in social concern regarding pathological gaming among adolescents, the WHO (World Health Organization) included "gaming disorder" in the International Classification of Disorders, 11th version (ICD-11). However, little longitudinal research has been conducted examining social influences on pathological gaming, particularly in Asian countries (e.g., South Korea, China). With 4-year panel data from young adolescents (N = 968, 50.7% girls; Mage = 13.3 years) in South Korea, this study examined the effects of cultural environmental factors (parents' excessive interference, communication with parents, and friends' and teachers' support) on pathological gaming through academic stress and self-control. The results showed the critical role of academic stress and self-control in the effects of environmental factors on pathological gaming. Parents' excessive interference increased the degree to which youth experienced academic stress while the degree of communication with parents decreased this stress. Increased academic stress damaged self-control, which finally increased the degree of pathological gaming. Self-control affected the degree of pathological gaming stronger than gaming time did. The theoretical and practical implications from the study findings are discussed.

Design of microemulsion system suitable for the oral delivery of poorly aqueous soluble beta-carotene.

Beta-carotene is a potent antioxidant for maintaining human health. However, its oral absorption is low due to poor aqueous solubility of less than 1 µg/ml. A microemulsion delivery system was designed to solubilize beta-carotene toward enhancing its oral bioavailability. From seven pseudoternary diagrams constructed, three systems were selected with large microemulsion areas suitable for oral administration and dilution in the predominately aqueous gastrointestinal fluids. Conductivity and rheology characterization were conducted along four dilution lines within the selected systems. Three pseudoternary-phase diagrams were selected with large microemulsion regions, >60% of the total phase diagram area, which provide microemulsions with higher drug-loading capacity. A phenomenon was observed by which both propylene glycol and Capmul MCM EP stabilize the microstructure of the microemulsions has been proposed based on the characterization studies. An optimal bicontinuous microemulsion formulation was selected comprising 12% orange oil, 24% Capmul MCM, 18% Tween 20, 6% Labrasol, 20% propylene glycol and 20% water, with a high beta-carotene loading capacity of 140.8 µg/ml and droplet size of 117.4 nm. In conclusion, the developed novel microemulsion formulation allows solubilizing beta-carotene and is a promising basis for further development as a functional beverage.

Kinetic stability and cellular uptake of lutein in WPI-stabilised nanoemulsions and emulsions prepared by emulsification and solvent evaporation method.

The particle size and lutein encapsulation efficiency of nanoemulsions prepared by emulsification and solvent evaporation method were 68.8±0.3nm and 80.7±0.8%, respectively, whereas they were 147.3±0.6nm and 86.3±0.3% for conventional emulsions. All the emulsions had no change in their particle size during storage (28days at 5, 20 and 40°C) but their lutein content and emulsion colour decreased, especially at 40°C. The lutein emulsions were analysed using MTT assay on the gut enterocyte cell line Caco-2 and they showed no toxicity as the cell viability was more than 80% at 10times or higher dilution after 24h of incubation. However, there was a higher cellular uptake of lutein by Caco-2 cells in nanoemulsions (872.9±88.3pmol/mgprotein) than conventional emulsions (329.5±214.6pmol/mgprotein). The results of this study indicated that nanoemulsions can be used as a delivery system to improve the cellular uptake of lutein.

Physicochemical properties of whey protein, lactoferrin and Tween 20 stabilised nanoemulsions: Effect of temperature, pH and salt.

Oil-in-water nanoemulsions were prepared by emulsification and solvent evaporation using whey protein isolate (WPI), lactoferrin and Tween 20 as emulsifiers. Protein-stabilised nanoemulsions showed a decrease in particle size with increasing protein concentration from 0.25% to 1% (w/w) level with Z-average diameter between 70 and 90 nm. However, larger droplets were produced by Tween 20 (120-450 nm) especially at concentration above 0.75% (w/w). The stability of nanoemulsions to temperature (30-90°C), pH (2-10) and ionic strength (0-500 mM NaCl or 0-90 mM CaCl2) was also tested. Tween 20 nanoemulsions were unstable to heat treatment at 90°C for 15 min. WPI-stabilised nanoemulsions exhibited droplet aggregation near the isoelectric point at pH 4.5 and 5 and they were also unstable at salt concentration above 30 mM CaCl2. These results indicated that stable nanoemulsions can be prepared by careful selection of emulsifiers.

Antioxidant activity and bioaccessibility of size-different nanoemulsions for lycopene-enriched tomato extract.

Lycopene nanoemulsions were prepared to protect the antioxidant activity and improve the bioaccessibility of lycopene-enriched tomato extract (containing 6% of lycopene) by an emulsification-evaporation method. Lycopene nanoemulsions, with droplet sizes between 100 and 200 nm, exhibited higher anti-radical efficiency and antioxidant activity, than did those smaller than 100 nm. Strong protectability of lycopene in droplets smaller than 100 nm was associated with relatively slower rates of DPPH and ABTS reactions. In vitro bioaccessibility values of lycopene-enriched tomato extract, lycopene nanoemulsions with droplets larger than 100 nm (approximately 150 nm on average), and lycopene nanoemulsions with droplets smaller than 100 nm (69 nm on average) were 0.01, 0.53, and 0.77, respectively. Interestingly, nanoemulsions with droplets smaller than 100 nm showed the highest in vitro bioaccessibility, which could be interpreted as evidence of nanoemulsification enhancing the in vitro bioaccessibility of lycopene.

Formulation of oil-in-water ß-carotene microemulsions: effect of oil type and fatty acid chain length.

The impact of oil type and fatty acid chain length on the development of food-grade microemulsions for the entrapment of ß-carotene was investigated. The microemulsion region of a ternary phase diagram containing short chain monoglycerides was larger than for di- and triglycerides when Tween 80 was used as surfactant. The cytotoxicity of microemulsions composed of a 30% monoglyceride oil, 20% Tween 80 and 50% aqueous buffer were evaluated using an in vitro cell culture model (human epithelial colorectal adenocarcinoma, Caco-2). The cytotoxicity test showed that the viability of Caco-2 cells against ß-carotene microemulsions at concentrations of 0.03125% (v/v) was higher than 90%. This study suggests that short chain monoglycerides could be used with Tween 80 to prepare transparent ß-carotene-encapsulated O/W microemulsions in the particle size range of 12-100 nm.

Physicochemical behaviour of WPI-stabilized emulsions in in vitro gastric and intestinal conditions.

Most studies on the in vitro lipid digestion of protein-stabilized emulsions have been carried out under simulated gastric and intestinal conditions. In this study, the digestion behaviour of whey protein isolate (WPI)-stabilized emulsions was examined under simulated intestinal fluid (SIF) conditions (pH 7.5, 2.5mg bile salts/mL and 0.8 mg pancreatin/mL) after the emulsions had been digested in a model simulated gastric fluid (SGF) containing pepsin (pH 1.6 and 3.2mg pepsin/mL) for different times. The droplet size, ζ-potential, microstructure, surface protein and amount of free fatty acids released were examined. The results indicated that WPI emulsions did not undergo pronounced changes in droplet size and microstructure during SGF digestion followed by coalescence during the subsequent SIF digestion. When WPI emulsions were treated with SGF, α-lactalbumin and a portion of ß-lactoglobulin proteins adsorbed at the interface were hydrolysed by pepsin, resulting in small peptides being produced as characterized by sodium dodecyl sulphate polyacrylamide gel electrophoresis. In general, digestion in SGF containing pepsin accelerated coalescence of the emulsion droplets during subsequent digestion in SIF containing pancreatic lipase. However, the changes in the size, the microstructure and the proteolysis of the interfacial proteins of the emulsions under gastric conditions did not influence the rate and the extent of lipid digestion in the subsequent intestinal environment.

The effect of cell immobilization on the antibacterial activity of Lactobacillus reuteri DPC16 cells during passage through a simulated gastrointestinal tract system.

Cell immobilization has the ability to influence the survival and functional characteristics of probiotic bacterial strains in harsh environments. This study investigated the effect of cell immobilization and passage through a simulated gastrointestinal tract (GI) on the antibacterial activity of Lactobacillus reuteri DPC16. Antibacterial activity, reuterin production and diol dehydratase activity were assayed in recovered isolates of L. reuteri that had been immobilized in Ca alginate-skim milk, and incubated in simulated GI fluids. Among all the recovered isolates tested, any that had undergone immobilization followed by immediate recovery of the cells without subsequent incubation in any fluids demonstrated the highest reuterin production, antimicrobial activity and diol dehydratase enzyme activity. L. reuteri DPC16 cells that had been immobilized, incubated in simulated GI fluids, and subsequently recovered from the beads often showed some loss of antimicrobial activity compared to the immobilized cells. The data confirm that the process of immobilization of L. reuteri in Ca alginate-skim milk, rather than the passage through simulated GI fluids, resulted in enhanced antibacterial activity. This is attributed to increased diol dehydratase activity, resulting in increased reuterin production.

Functional properties of free and encapsulated Lactobacillus reuteri DPC16 during and after passage through a simulated gastrointestinal tract.

Lactobacillus reuteri DPC16 is a probiotic bacterium that has strong antimicrobial activities on pathogens, mainly due to its ability to produce reuterin, an antimicrobial compound. The objective of this study was to examine the ability of an encapsulation technique to protect the functional properties of cells of L. reuteri DPC16 during passage through a simulated GI tract. The functional properties of the cells were studied before and after passage through the tract. An alginate-skim milk encapsulation system was used to deliver the probiotic bacterium through the simulated GI tract, allowing for the release of the cells into the simulated colonic fluid. The cells were then isolated and cultured. The recovered cells showed no diminution in functional properties, including their growth kinetics, ability to adhere to epithelial cells and ability to inhibit the adhesion of E. coli to epithelial cells. The bacteriostatic and bactericidal properties of the recovered cells against some pathogens were significantly greater (P < 0.05) than those of the original cells. Production of reuterin by the recovered cells was significantly greater than that of the original cells when cultured in MRS medium in the absence of its metabolic precursor, glycerol. The results demonstrate significant consequences for the application of the encapsulation technique to protect and/or enhance the functional properties of the probiotic cells.

Influence of gastric digestive reaction on subsequent in vitro intestinal digestion of sodium caseinate-stabilized emulsions.

In this study, in vitro intestinal lipid digestion and the physicochemical and microstructural changes of sodium caseinate-stabilized emulsions were examined after the emulsions had been digested in a model simulated gastric fluid containing pepsin for different times. The average size, size distribution, microstructure, proteolysis of interfacial proteins and lipolysis of the emulsion droplets were monitored as a function of digestion time. The emulsion droplets underwent extensive droplet flocculation, with some coalescence together with proteolysis of interfacial proteins, in simulated gastric fluid, resulting in changes in the droplet size and the microstructure of the emulsions. In general, digestion in simulated gastric fluid containing pepsin accelerated coalescence of the emulsion droplets during subsequent digestion in simulated intestinal fluid containing pancreatic lipase. However, the changes in the size, the microstructure and the proteolysis of the interfacial proteins of the emulsions under gastric conditions did not influence the rate and the extent of lipid digestion in the subsequent intestinal environment.

Protein-stabilized nanoemulsions and emulsions: comparison of physicochemical stability, lipid oxidation, and lipase digestibility.

The properties of whey protein isolate (WPI) stabilized oil-in-water (O/W) nanoemulsions (d(43) ≈ 66 nm; 0.5% oil, 0.9% WPI) and emulsions (d(43) ≈ 325 nm; 0.5% oil, 0.045% WPI) were compared. Emulsions were prepared by high-pressure homogenization, while nanoemulsions were prepared by high-pressure homogenization and solvent (ethyl acetate) evaporation. The effects of pH, ionic strength (0-500 mM NaCl), thermal treatment (30-90 °C), and freezing/thawing on the stability and properties of the nanoemulsions and emulsions were compared. In general, nanoemulsions had better stability to droplet aggregation and creaming than emulsions. The nanoemulsions were unstable to droplet flocculation near the isoelectric point of WPI but remained stable at higher or lower pH values. In addition, the nanoemulsions were stable to salt addition, thermal treatment, and freezing/thawing (pH 7). Lipid oxidation was faster in nanoemulsions than emulsions, which was attributed to the increased surface area. Lipase digestibility of lipids was slower in nanoemulsions than emulsions, which was attributed to changes in interfacial structure and protein content. These results have important consequences for the design and utilization of food-grade nanoemulsions.

Chemical changes in bovine milk fat globule membrane caused by heat treatment and homogenization of whole milk.

The effects of heat treatment and homogenization of whole milk on chemical changes in the milk fat globule membrane (MFGM) were investigated. Heating at 80 degrees C for 3-18 min caused an incorporation of whey proteins, especially beta-lactoglobulin (beta-Ig), into MFGM, thus increasing the protein content of the membrane and decreasing the lipid. SDS-PAGE showed that membrane glycoproteins, such as PAS-6 and PAS-7, had disappeared or were weakly stained in the gel due to heating of the milk. Heating also decreased free sulphydryl (SH) groups in the MFGM and increased disulphide (SS) groups, suggesting that incorporation of beta-Ig might be due to association with membrane proteins via disulphide bonds. In contrast, homogenization caused an adsorption of caseins to the MFGM but no binding of whey proteins to the MFGM without heating. Binding of caseins and whey proteins and loss of membrane proteins were not significantly different between milk samples that were homogenized before and after heating. Viscosity of whole milk was increased when milk was treated with both homogenization and heating.