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Exploring the emergence of cooperation in the populations of self-interested individuals is of huge challenge. Evolutionary game theory has been utilized to investigate the evolution of cooperation. In recent years, many researchers have paid massive attention on the evolution of cooperative behavior from the perspective of multiple games, especially the transition of games. Nevertheless, not only are the current interactive actions crucial, but also the historical interactive experience is fateful. Motivated by this, the persistence-based game transition mechanism is proposed and introduced to investigate the evolution of cooperation, where both the current pairwise strategies and the persistence of the pairwise strategies determine the game played in the next time step. Through analyzing the evolutionary results of strategies and games, we find that the cooperation can be facilitated by the enhanced network reciprocity as the persistence-based game transition makes mutual cooperators play games with weak dilemma more persistently. • A persistence-based game transition is proposed in multi-games. • In our model, both pairwise interactive strategies and the persistence of pairwise strategies determine the game transition. • The persistence-based game transition can facilitate cooperation through enhancing network reciprocity. [ABSTRACT FROM AUTHOR]

Exploring the emergence and maintenance of cooperation in social dilemma is valuable and it arises considerable concerns of many researchers. In this paper, we propose a mechanism to promote cooperation, called benefit community, in which cooperators linking together form a common benefit community and all their payoffs obtained from game are divided coequally. The robustness of conclusions is tested for the PDG (prisoners' dilemma game) on square lattice and WS small world network. We find that cooperation can be promoted by this typical mechanism, especially, it can diffuse and prevail more easily and rapidly on the WS small world network than it on the square lattice, even if a big temptation to defect b. Our research provides a feasible direction to resolve the social dilemma. [ABSTRACT FROM AUTHOR]

Herbivores strongly affect the ecological structure and functioning in seagrass bed ecosystems, but may exhibit density-dependent effects on primary producers and carbon sequestration. This study examined the effects of herbivorous snail (Cerithidea rhizophorarum) density on snail intraspecific competition and diet, dominant seagrass (Thalassia hemprichii) and epiphyte growth metrics, and sediment organic carbon (SOC). The growth rates of the herbivorous snail under low density (421 ind m−2) and mid density (842 ind m−2) were almost two times of those at extremely high density (1684 ind m−2), indicating strong intraspecific competition at high density. Herbivorous snails markedly reduced the epiphyte biomass on seagrass leaves. Additionally, the seagrass contribution to herbivorous snail as food source under high density was about 1.5 times of that under low density, while the epiphyte contribution under low density was 3 times of that under high density. A moderate density of herbivorous snails enhanced leaf length, carbon, nitrogen, total phenol and flavonoid contents of seagrasses, as well as surface SOC content and activities of polyphenol oxidase and β-glucosidase. However, high density of herbivorous snails decreased leaf glucose, fructose, detritus carbon, and total phenols contents of seagrasses, as well as surface SOC content and activities of polyphenol oxidase and β-glucosidase. Therefore, the effects of herbivorous snail on seagrass, epiphyte and SOC were density-dependent, and moderate density of herbivorous snail could be beneficial for seagrasses to increase productivity. This provided theoretical guidance for enhancing carbon sink in seagrass bed and its better conservation. [Display omitted] • Intraspecific competition inhibited herbivorous snail growth. • The presence of herbivorous snail markedly reduced the epiphyte biomass. • Moderate snail density facilitated seagrass by removing epiphyte and enhanced SOC. • High snail density adversely affected seagrass and sediment carbon sequestration. • Cultivate herbivore in moderate density benefits seagrass conservation. [ABSTRACT FROM AUTHOR]

Considering congestion effects in realistic network environments, we give a new method to adjust dynamically adjust the weight of the congested edge. We calculate the load on an edge based on the revised betweenness method and propose a novel model with three states of edges to investigate the dynamics of cascading failures in the ring network, the BA scale-free network, and the real traffic networks in London. By two robust metrics, we surprisingly observe the abnormal dynamics of cascading propagation, especially compared with that in the unadjustable weight, the curves of cascading dynamics in the adjustable weight are more irregular, which means that enhancing the capacity of each edge is not always better to avoid the cascading propagation. In addition, our simulation results show that the dynamical change of the edge's weight makes the heterogeneous BA networks more vulnerable. [ABSTRACT FROM AUTHOR]

In repeated games, historical interactions lead to varying environment. Among existing studies, the variation of environment or game is basically considered from the perspective of nodes, while in pairwise game, it is more reasonable to consider the interactive environment from the perspective of edges. In addition, since historical interactive experience of pairwise players has an impact on the current interactive environment, the duration of pairwise strategies produces differentiated results. Therefore, we consider the persistence-dependent dynamic interactive environment where the persistence of pairwise strategy affects the weight between two interacting players, and the game resource of interactive environment is influenced by varying weight. The results suggest that the introduction of persistence-dependent dynamic interactive environment can effectively enhance cooperation, and a larger weight increment of CD link generates a higher cooperation level as it indicates that the reward for cooperative behavior is significant, although a single cooperator for the pairwise interacting players. • We introduce the persistence-dependent dynamic interactive environment in prisoner's dilemma game. • An intermediate variable, weight, is introduced and influenced by the strategy persistence of pairwise players. • The fluctuation scale of weight is dependent on distinct kinds of edge links, and a parameter η for CD link is introduced. • The variation of weight determines the changing resources for the interactive environment. • Our new model can boost cooperation significantly, especially for the larger η. [ABSTRACT FROM AUTHOR]

Background: Pulmonary rehabilitation (PR) has been recognized to be an effective therapy for chronic obstructive pulmonary disease (COPD). However, in China, the application of PR interventions is still less promoted. Therefore, this cross-sectional study aimed to understand COPD patients' intention to receive PR, capture the potential personal, social and environmental barriers preventing their willingness of receiving PR, and eventually identify demanding PR services with the highest priority from patients' point of view. Methods: In total 237 COPD patients were recruited from 8 health care facilities in Zhejiang, China. A self-designed questionnaire was applied to investigate patients' intention to participate in PR and potentially associated factors, including personal dimension such as personal awareness, demographic factors, COPD status and health-related literacy/behaviors, as well as social policies and perceived environmental barriers. The demand questionnaire of PR interventions based on the Kano model was further adopted. Results: Among the 237 COPD patients, 75.1% of COPD patients were willing to participate in PR interventions, while only 62.9% of the investigated patients had heard of PR interventions. Over 90% of patients believed that the cost of PR services and the ratio of medical insurance reimbursement were potential obstacles hindering them from accepting PR services. The multiple linear regression analysis indicated that the PR skills of medical staff, knowledge promotion and public education levels of PR in the community, patients' transportation concerns and degree of support from family and friends were significantly associated with willingness of participation in PR interventions. By using the Kano model, the top 9 most-requisite PR services (i.e., one-dimensional qualities) were identified from patients' point of view, which are mainly diet guidance, education interventions, psychological interventions and lower limb exercise interventions. Subgroup analysis also revealed that patients' demographics, such as breathlessness level, age, education and income levels, could influence their choice of priorities for PR services, especially services related to exercise interventions, respiratory muscle training, oxygen therapy and expectoration. Conclusions: This study suggested that PR-related knowledge education among patients and their family, as well as providing basic package of PR services with the most-requisite PR items to COPD patients, were considerable approaches to promote PR attendance in the future. [ABSTRACT FROM AUTHOR]

Prevalence of cooperation within groups of selfish individuals is puzzling in that it contradicts with the basic premise of natural selection. Grasping the force that fosters and sustains cooperative behaviors is thus of central importance for the understandings of how companies develop and how societies thrive. In this paper, by means of evolutionary game theory, we refresh the strategy updating rule to be matched with a more realistic scenario where individuals choose someone excellent as the role model and improve themselves continuously to narrow the gap. Under the force of role model, individuals adjust their instantaneous strategy with the increment δ in the next continuous M time steps. And a new role model needs to be selected unless its payoff is more than the focal player's. The computer simulation results illustrate that the self-improvement driven by role model facilitate group cooperation significantly, and the slow but persistent self-improvement performs better. Therefore, in order to achieve higher enterprise performance and build a more harmonious society, managers and government officials should spare no effort to encourage people to keep improving themselves to keep up with their role models. • A new strategy updating rule, self-improvement driven by role model updating rule is proposed. • Players make self-improvement according to the persistent choosing reference roles. • The simulation results show that a slow but persistent self-improvemnet enhances cooperation markedly. [ABSTRACT FROM AUTHOR]

In previous studies about heterogeneous investment, many researchers only focus on the monodirectional effect of reputation, but ignore the reversed influence about the heterogeneity of reputation fluctuation driven by investment. Given this, considering the interplay between reputation and heterogeneous investment, we explore the evolution of cooperation in public goods game. In detail, each player's reputation situations in different groups determine its differentiated investment amounts, and in turn, the heterogeneity of reputation fluctuation is dependent on how much it invests into each group. Furthermore, we introduce two parameters, α and β , to characterize the effect degree of investment on heterogeneous reputation fluctuation and the one of reputation on heterogeneous investment, respectively. The simulation results suggest that cooperation can be boosted to some extent, especially for the larger α and β , as they magnify the interplay of reputation and heterogeneous investment. • We introduce the interplay between reputation and heterogeneous investment in the public goods game. • Reputation effects unequal investment and heterogeneous reputation fluctuation is effected by investment in turn. • We introduce parameter α to characterize the effect degree of investment on heterogeneous reputation fluctuation. • Parameter β is presented to denote the effect degree of reputation on heterogeneous investment. • Our new model can boost cooperation significantly, especially for the larger α and β. [ABSTRACT FROM AUTHOR]

• A new framework of multiple public goods games considering the persistence and transition of games is proposed. • The heterogeneous public resource of public goods game evolves with the persistence and transition of games. • Our new model can promote cooperation effectively, especially under the condition with scarce resource. Many various projects may exist in an enterprise in parallel, which leads to distinct group interactions. Team members cooperate in their respective projects, and sometimes it is possible to engage in several concurrent projects. Owing to practice makes perfect, the longer the duration of members participating in an identical project is, the higher benefits will be under same contribution. However, in a fiercely competitive environment, a huge conflict of interest between groups and individuals which results in social dilemma makes projects difficult to proceed smoothly. The experience of direct reciprocity shows that repeated interactions can alleviate this problem, but most multi-person dilemma studies consider a single game scenario, and public resources remain constant. Here we introduce a general framework of multiple public goods games. Taking the public goods game with threshold into consideration, public resource evolves with the persistence and transition of games. Our results suggest although collaborators are at a disadvantage in different game scenarios, our model can still effectively promote the overall cooperation in multiple public goods games. Especially, it performs better when public resource is relative scarce. [ABSTRACT FROM AUTHOR]

• A reputation-based strategy persistence mechanism in evolutionary game is proposed. • Our mechanism illuminates that the scale of reputation fluctuation totally depends on the persistence of last strategy. • A parameter, α , illustrating the impact of strategy persistence on reputation variation, is introduced. • Cooperation can be promoted effectively by our new mechanism. Understanding the emergence and maintenance of cooperation in social dilemma has received a lot of attention. In previous research, many scholars found that the reputation mechanism can promote cooperation, and the variation of reputation is consistent. However, in reality, according to both one's current action and past experiences, every individual's impression from others is modified to varying extent everyday. In other words, the length of duration of the same performance influences the diverse scale of their own reputation fluctuation. Therefore, a reputation-based strategy persistence mechanism, in which the increment of current reputation is determined by the persistence of last strategy, is proposed. Moreover, we introduce a parameter α to illustrate the impact of strategy persistence on reputation variation. The results of simulation show that the new mechanism paves the way for cooperation in evolutionary game, and the smaller α is, the better the mechanism performs. [ABSTRACT FROM AUTHOR]

Background: Allergic rhinitis is a common health concern that affects quality of life. This study aims to examine the online search trends of allergic rhinitis in China before and after the COVID-19 epidemic and to explore the association between the daily air quality and online search volumes of allergic rhinitis in Beijing. Methods: We extracted the online search data of allergic rhinitis-related keywords from the Baidu index database from January 23, 2017 to June 23, 2022. We analyzed and compared the temporal distribution of online search behaviors across different themes of allergic rhinitis before and after the COVID-19 pandemic in mainland China, using the Baidu search index (BSI). We also obtained the air quality index (AQI) data in Beijing and assessed its correlation with daily BSIs of allergic rhinitis. Results: The online search for allergic rhinitis in China showed significant seasonal variations, with two peaks each year in spring from March to May and autumn from August and October. The BSI of total allergic rhinitis-related searches increased gradually from 2017 to 2019, reaching a peak in April 2019, and declined after the COVID-19 pandemic, especially in the first half of 2020. The BSI for all allergic rhinitis themes was significantly lower after the COVID-19 pandemic than before (all p values < 0.05). The results also revealed that, in Beijing, there was a significant negative association between daily BSI and AQI for each allergic rhinitis theme during the original variant strain epidemic period and a significant positive correlation during the Omicron variant period. Conclusion: Both air quality and the interventions used for COVID-19 pandemic, including national and local quarantines and mask wearing behaviors, may have affected the incidence and public concern about allergic rhinitis in China. The online search trends can serve as a valuable tool for tracking real-time public concerns about allergic rhinitis. By complementing traditional disease monitoring systems of health departments, these search trends can also offer insights into the patterns of disease outbreaks. Additionally, they can provide references and suggestions regarding the public's knowledge demands related to allergic rhinitis, which can further be instrumental in developing targeted strategies to enhance population-based disease education on allergic diseases. [ABSTRACT FROM AUTHOR]

How to effectively maintain costly intra-group cooperation has always been a topic of great concern in society. As we all know, inter-group competition is a constructive way to promote intra-group cooperation. Previous inter-group competition mechanisms are primarily based on the total contribution value of all individuals in the group in the current round, which ignore the historical behavior of the group and its members. For comparison, we argue that the introduction of collective reputation which reflects not only the total contribution of the groups in the current round but also the group's historical behavior is necessary for the construction of an inter-group competition model. Furthermore, an excellent collective reputation can help the group obtain more high-quality resources and help the group stand out from the competition. To this end, we introduce a new mechanism of inter-group transfer payment driven by collective reputation and construct a public goods game (PGG) model of inter-group competition to study the dynamic behavior of intra-group cooperation evolution. Two parameters, the proportion of accepted groups a and the proportion of transferred groups b , are introduced. The simulation results suggest that the effectiveness of this model in promoting cooperation depends largely on the joint settings of a and b. And in most cases, the combination of small a and medium b plays the significant role. [ABSTRACT FROM AUTHOR]

In previous studies of evolutionary games, players change reference objects at each time step. However, in real life, many people tend to consistently imitate outstanding role models instead of changing reference objects frequently. From this, a persistent imitation rule is proposed. In detail, a persistent imitator will persist in imitating his or her reference object until the wealth exceeds that of the reference object or the duration of continuous imitation exceeds a specific value. Furthermore, to reflect inter-individual differences, we divide the players into two categories, persistent imitators and random imitators. The simulation suggests that the presence of a high proportion of persistent imitators has a significant effect on the development of cooperation, and the level of cooperation increases as the maximum duration of imitation increases. However, when the proportion of persistent imitators or the maximum duration of imitation is small, the promotion effect on cooperation is not obvious. • The persistent imitation of reference objects is proposed. • Persistent imitators refresh the role model if their payoff exceeds the last one's. • After the maximum duration, the persistent imitator chooses a new reference object. • The presence of persistent imitators can effectively facilitate cooperation. [ABSTRACT FROM AUTHOR]

Background: Sediment is crucial for the unique marine angiosperm seagrass growth and successful restoration. Sediment modification induced by eutrophication also exacerbates seagrass decline and reduces plantation and transplantation survival rates. However, we lack information regarding the influence of sediment on seagrass photosynthesis and the metabolics, especially regarding the key secondary metabolic flavone. Meanwhile, sulfation of flavonoids in seagrass may mitigate sulfide intrusion, but limited evidence is available. Results: We cultured the seagrass Thalassia hemprichii under controlled laboratory conditions in three sediment types by combining different ratios of in-situ eutrophic sediment and coarse beach sand. We examined the effects of beach sand mixed with natural eutrophic sediments on seagrass using photobiology, metabolomics and isotope labelling approaches. Seagrasses grown in eutrophic sediments mixed with beach sand exhibited significantly higher photosynthetic activity, with a larger relative maximum electron transport rate and minimum saturating irradiance. Simultaneously, considerably greater belowground amino acid and flavonoid concentrations were observed to counteract anoxic stress in eutrophic sediments without mixed beach sand. This led to more positive belowground stable sulfur isotope ratios in eutrophic sediments with a lower Eh. Conclusions: These results indicated that coarse beach sand indirectly enhanced photosynthesis in T. hemprichii by reducing sulfide intrusion with lower amino acid and flavonoid concentrations. This could explain why T. hemprichii often grows better on coarse sand substrates. Therefore, it is imperative to consider adding beach sand to sediments to improve the environmental conditions for seagrass and restore seagrass in eutrophic ecosystems. [ABSTRACT FROM AUTHOR]

objective*To screen new potential pathogenic genes in the course of esophageal squamous cell carcinoma. Methods*The data of miRNA chips GSE122497 and GSE164174 were obtained by GEO database. The differential mirnas of esophageal cancer patients and healthy people were screened by GEO2R, and the intersection was obtained by Venn Diagram Webtool. Target Scan tool and DIANATOOLS tool were used to predict the target genes of differential miRNA, and the intersection of predicted target genes of the two tools was used for gene function analysis. The protein interactions of target genes were analyzed by using STRING tool and Hub genes were selected. Results*(1) A total of 108 differential miRNAs were detected in the chip. (2) After taking the intersection of Target Scan tool and DIANATOOLS tool, there were 1 354 different target genes. (3) Gene Ontology (GO) analysis showed that gene functions of differential target genes were significantly enriched in biological processes such as DNA template transcriptional regulation and RNA polymerase II promoter transcriptional regulation, as well as RNA polymerase II core promoter proximal sequence specific DNA binding, protein binding, metal ion binding and other molecular functions. It mainly existed in nucleus, cytoplasm, cytoplasm and other cellular components. In descending order of the number of enriched genes, Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis showed that the above genes were significantly enriched in tumor pathway, MAPK signaling pathway, stem cell pluripotency regulation signaling pathway, etc. (4) There were 1 326 nodes and 2 300 edges in the protein interaction network, and the average node connectivity was 3.47. The selected Hub genes were SMAD specific E3 ubiquitin protein ligase 2 (SMURF2), β-transducin repeat containing E3 ubiquitin protein ligase (BTRC), SMAD specific E3 ubiquitin protein ligase 1 (SMURF 1), ubiquitin conjugating enzyme E2 D1 (UBE2D1), and cullin 2 (CUL2). Previous studies have shown that the above genes are related to ubiquitination. Conclusion*SMURF2, BTRC, SMURF1, UBE2D1 and CUL2 genes screened from GEO database may be involved in the disease process of esophageal squamous cell carcinoma through the ubiquitin of targeted regulatory proteins. [ABSTRACT FROM AUTHOR]

Previous experience suggests that prior agreement (a mechanism to test how strongly peers are committed to a common goal) and posterior compensation (a way to compensate cooperators by punishing defectors who violate their commitments) together contribute to the flourishing of cooperation. Far less is known, however, how the determination of the optimal threshold for prior agreement in force and the posterior compensation affect collaboration, and the relevance of different strategies. Here, in the context of public goods games and using an evolutionary game theory model, we investigate the evolution of cooperation and the relevance of different strategies by introducing prior agreements and posterior compensation in structured populations. Analytical results show that posterior compensation does not always promote cooperation and that there are sudden increases and decreases in the first-order phase transition. Interestingly, prior agreements without posterior compensation can also effectively restrain defectors, with cooperation abundance remaining at a high level. Furthermore, the threshold of effective agreement has nonlinear effects on cooperation, with cooperation abundance peaking at intermediate thresholds under specific parameters. • The prior agreements and posterior compensation are introduced in network reciprocity. • The model aims to determine the optimal threshold of agreements and the correlation between different strategies. • The effects of posterior compensation and the threshold of agreements in force on the proportion of cooperation are not linear. [ABSTRACT FROM AUTHOR]

Identifying the most influential individuals in structured populations is an important research topic throughout network science. Previous studies, whether identifying the initial cooperators in a network that can lead to the spread of cooperation or assessing the chances that an intrusive defector may lead to the collapse of cooperation, have assumed that all individual attributes are homogeneous. However, heterogeneity among humans is widespread and can sometimes affect cooperation and welfare. For example, the layout of non-cooperative individuals in cooperative individuals inhibits the evolution of cooperation. Therefore, specifying the heterogeneity of individuals and studying the effect of their initial position on cooperation is the focus of our attention. Here we hypothesize that individuals in the network are divided into cooperative and non-cooperative individuals according to the heterogeneity of social value orientations, and we investigate the effects of the initial position of non-cooperative individuals on cooperation by adding them through different ranking rules to the network composed of cooperative individuals. We investigate separately the effects of the proportion of non-cooperative individuals, the proportion of initial cooperators of different types of individuals and different game scenarios on cooperation under different ranking rules. The results show that the addition of non-cooperative individuals to cooperative populations can effectively hinder the spread of cooperation. We also find that the proportion of initial cooperators for different types of individuals and the effects of different game types on population evolution also differ significantly under different ranking rules. • Identifying how the most influential individuals have an impact on the evolution of cooperation under different ranking rules. • Our model classifies individuals into non-cooperative and cooperative individuals through the heterogeneity of their social value orientations, and thus investigates the impact of strategically positioned non-cooperative individuals who tend to defect. • Non-cooperative individuals block cooperation between cooperative individuals; the initial proportion of different types of individuals as well as different game scenarios also have a significant effect on the evolution of cooperation. [ABSTRACT FROM AUTHOR]

This study aimed to identify the specimen type that has high positivity and its proper sampling time for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) testing to promote diagnostic efficiency. All SARS-CoV-2-infected patients with a laboratory-confirmed diagnosis in Zhoushan City were followed up for viral shedding in respiratory tract specimens and faecal samples. Positivity was analysed both qualitatively and quantitatively by proper statistical approaches with strong testing power. Viral shedding in respiratory tract and faecal specimens was prolonged to 45 and 40 days after the last exposure, respectively. The overall positive rate in respiratory tract specimens was low and relatively unstable, being higher in the early-to-mid stage than in the mid-to-late stage of the disease course. Compared with respiratory tract specimens, faecal samples had a higher viral load, higher overall positive rate, and more stable positivity in different disease courses and varied symptomatic status. Faecal specimens have the potential ability to surpass respiratory tract specimens in virus detection. Testing of faecal specimens in diagnosis, especially for identifying asymptomatic carriers, is recommended. Simultaneously, testing respiratory tract specimens at the early-to-mid stage is better than testing at the mid-to-late stage of the disease course. A relatively small sample size was noted, and statistical approaches were used to address it. Information was missing for both specimen types at different stages of the disease course due to censored data. Our research extends the observed viral shedding in both specimen types and highlights the importance of faecal specimen testing in SARS-CoV-2 diagnosis. Healthcare workers, patients, and the general public may all benefit from our study findings. Disposal of sewage from hospitals and residential areas should be performed cautiously because the virus sheds in faeces and can last for a long time. [ABSTRACT FROM AUTHOR]

In peer-to-peer interaction, people have conditions to adopt different strategies against different opponents, which is called interactive diversity. Recently, the evolution of cooperation under interactive diversity has attracted much attention, but the potential cost of maintaining interactive diversity is rarely considered. Actually, individuals may need to frequently switch their strategies between interactions with different opponents. If strategy switching is costly, individuals are likely to prefer strategies that can be maintained to strategies that require frequent changes. In other words, individuals may have behavioral inertia in their interactions with different opponents. Although some studies have found that appropriate strategy switching costs or inertia can promote cooperation under interactive identity, their role under interactive diversity remains to be further discussed. The main reason is that strategy switching costs may restrain the diversity of strategies, and the differentiation of strategies is exactly the key to cooperation under interactive diversity. In this work, we are devoted to reveal the impact of strategy switching costs on the evolution of cooperation under interactive diversity. Simulation results show that appropriate strategy switching costs are also positive under interactive diversity, but higher strategy switching costs play completely different roles in different networks. Especially, cooperation in lattice network sometimes shows a non-monotonic dependence of "first increasing, second decreasing and then increasing again" on unit switching cost. These findings are of great significance for understanding the emergence of cooperation in paired interaction under interactive diversity. • We study the effect of strategy switching costs under interactive diversity. • Small switching costs can promote cooperation on multiple networks. • Medium switching costs may hinder cooperation on lattice network. • Excessive switching costs in ER network and BA network are unbearable. • The reasons for the phenomenon differences across networks are analyzed. [ABSTRACT FROM AUTHOR]

Seagrass-herbivore interactions play a principal role in regulating the structure and function of coastal food webs, which were affected by nutrient enrichment. Seawater nutrient enrichment might change seagrass palatability by altering seagrass physical and chemical traits, consequently modulating herbivory patterns, but this remains elusive. In this study, the dominant tropical seagrass Thalassia hemprichii was cultured in different ammonium concentrations to examine the response of seagrass nutritional quality, deterrent secondary metabolites, and leaf toughness, as well as the subsequent effect of the changed physical (e.g., leaf toughness) and chemical traits (e.g., nitrogen content; total phenol) on the grazing activity of the herbivorous snail Cerithidea rhizophorarum. Ammonium enrichment enhanced seagrass nutritional quality and decreased physical defence. Low ammonium enrichment increased total phenol content, while high ammonium enrichment reduced it. Both low and high ammonium enrichment enhanced the grazing intensity of C. rhizophorarum on seagrass. Interestingly, nutritional quality mostly determined the herbivory preference of C. rhizophorarum on the intact seagrass having physical structure, with a chemical deterrent (total phenol) playing a secondary role. In contrast, chemical deterrent mainly determined the grazing intensity on agar seagrass food which was made artificially to exclude physical structure. This indicated that seagrass leaf physical structure might hinder phenol compounds from deterring herbivores. Overall, the results presented here demonstrate that ammonium enrichment remarkably increased seagrass palatability and subsequently induced higher susceptibility to herbivory, which might induce seagrass loss. Schematic pictures of the effects of ammonium enrichment on seagrass palatability and subsequent effects on herbivory. Symbols of Thalassia hemprichii are courtesy of the Integration and Application Network, University of Maryland Center for Environmental Science (http://ian.umces.edu/symbols/). The different sizes of symbols represent the relative sizes of seagrass leaf traits. [Display omitted] • Ammonium enrichment significantly increased seagrass palatability. • Nutritional quality mostly determined the feeding preference on intact seagrass. • Seagrass physical structure had an effect on reducing efficiency of chemical deterrents. [ABSTRACT FROM AUTHOR]

• The evolution of cooperation hypothesized that individual selection is inevitable is investigated. • Distinct from the traditional models, our model studied the effects of wealth-based rule when individual selection is inevitable, where only the top V individuals with relatively high cumulative payoffs in each group can be selected for costly PGG. • The effects of participation costs on the proportion of cooperation, the proportion of different individuals, and the gap between rich and poor individuals are distinctly different under different V. Individual selection, as an effective mechanism, is often used in spatial evolutionary games to promote cooperation. Previous research assumes that, individual selection usually occurs with people who fail to meet a certain criterion. However, individual selection is usually inevitable, regardless of whether players in population cooperate or defect. This paper studies the effects of wealth-based rule in costly public goods games when individual selection is inevitable. Specifically, we assume that only the top V individuals with relatively high cumulative payoffs in each group can be selected for costly PGG. The results show that when V is large, the increase of participation cost has slight inhibitory effects on the evolution of cooperation, but it alleviates the polarization of individuals. However, when V is small, the increase of participation cost within a certain range promotes cooperation prosperity, but it also causes an increase in the proportion of polarized individuals and a widening of the wealth gap between rich and poor individuals. [ABSTRACT FROM AUTHOR]

• The evolution of cooperation hypothesized that emotion can influence one's own willingness to change strategies is investigated. • Distinct from the traditional evolutionary model, our model hypothesized that individuals are divided into two categories, namely, non-competitive individuals and competitive individuals, and their emotion is considered quantifiable and cumulative. • The existence of non-competitive individuals has a significant positive effect on the survival of cooperators, but the presence of competitive individuals also makes non-competitive individuals much less effective in promoting cooperation. • The emotional cumulative length plays a key role in promoting overall cooperation, but surprisingly, the cooperation rate of competitive individuals peaks at an intermediate value of emotional cumulative length. Emotion emerges along with individuals' interactions, and numerous experimental studies have shown that emotion plays an important role in individual decision making. However, how emotion affects the evolution of cooperation in structured population is largely unknown. Here we introduce emotion into network reciprocity, where emotion is considered quantifiable and cumulative, and then divide individuals into two types, namely non-competitive individuals whose social value orientation is mutually beneficial and competitive individuals whose social value orientation is maximizing outcomes for the self. Here, we explore the effects of the proportion of non-competitive individuals and emotional cumulative length on the evolution of cooperation. Simulation results show that the existence of non-competitive individuals promotes cooperation in the system. Furthermore, we also find that emotional cumulative length plays a key role in promoting overall cooperation, but surprisingly, the cooperation rate of competitive individuals peaks at an intermediate value of emotional cumulative length. [ABSTRACT FROM AUTHOR]

Affected by geographical or social factors, human communities are organized with changeless groups for teamwork. Within groups, defection dominates because the payoffs of defectors are often higher than those of cooperators; among groups, higher cooperation level makes individuals wealthier. For the previous mechanism of evolutionary dynamics leading individuals to imitate the rich in their groups, defective strategy evolves. However, individuals who belong to different groups and have no direct interaction of interests actually could influence each other. Due to the similarity of environment, the strategies among groups have the channel and necessity of dissemination. To this end, we propose an evolutionary game model with inter-group selection of strategy. By simulations, the effects of groups' selection preference, group size, multiplier factor, imitation intensity and competition among groups on cooperative evolution in populations are studied. We find that when the group makes selection without preference, the intensity of the choice positively affects the level of cooperation; the strategy selection with preference can effectively increase the group cooperation rate. • An evolutionary game model considering inter-group selection of strategy is proposed. • A player in one group can imitate strategy of individuals in other groups. • The preference and other factors have been considered in evolutionary game. • Cooperation can be promoted effectively by our new mechanism. [ABSTRACT FROM AUTHOR]

It is known that the vaccination is essential for suppressing the periodic prevalence of an infectious disease, while the vaccination decision is influenced by external factors. Whether or not to take vaccination depends not only on the expected benefit of individual, but also on the behavior of others. Nowadays, the speed of information transmission on the social media is fast with wide range, which extremely expands the scope of imitation, but it is unknown whether it is beneficial to vaccination. Inspired by this situation, a vaccination game model on two-layer network which increases the intensity of information sharing is proposed. The vaccination game layer and the information sharing layer are established to study the interaction between individual vaccination decisions and strategic exchanges. We find that although information sharing has inhibited individual vaccination decisions to some extent, the overall scale of disease spreading in society has decreased with increasing information sharing. • A new mechanism, information sharing, in evolutionary vaccination game is introduced. • The vaccination game model in two-layer network are taken into account. • The spread of epidemics is effectively suppressed under the information sharing mechanism. [ABSTRACT FROM AUTHOR]

Reports on the regulation region of larval serum protein gene, Bombyx mori, (BmLSP). Indication that the first intron, the first exon, the central promoter region and 5'-upstream region, is cloned from genomic DNA of the silkworm, SujuxMinghu; Use of PCR and restriction endonuclease methods; Construction of a series of luciferase reporter plasmids, driven by different length of BmLSP promoters; Investigation into the regulation elements and foreign insect hormones' effect on the BmLSP promoter activity, via the transient expression system in BmN cells; Finding that the BmLSP promoter activity is higher; Result when the first intron or the element in 5'-upstream region harboring the homologous sequence with the first intron of light-chain fibroin gene (EHIF) is deleted; Suggestion that the first intron and EHIF contain the main positive cis-acting elements; The negative effect of the inactive mariner transposable element (MTE); Effects of juvenile hormone analogue (JHA) on the BmLSP promoter activity demonstrating a dose-dependent manner; Idea that low concentration treatments increase the BmLSP promoter activity, while high concentration treatments decrease it; Assertion that insect ecdysone (MH) treatments present no significant effect.