Transitions in the cell-fate induction induced by colored noise associated with the inductive stimulus.

The cell-fate induction based on the saddle-node bifurcation is undoubtedly a very important concept in developmental biology, which provides a possible mechanism to explain the intrinsic irreversibility in the developmental process. In this paper, the effect of a colored noise, which is associated with the inductive stimulus, on the saddle-node landscape of cell-fate induction is investigated, especially, the effect of the change of correlation time of colored noise on cell-fate induction. The main results show clearly that the change of correlation time of colored noise could induce the transitions of the system. This implies that the colored noise associated with inductive stimulus may have a profound effect on the saddle-node bifurcation landscape of cell-fate induction. This will also help us to understand more deeply the role of cell-fate induction in developmental biology.

Imitation dynamics with time delay.

Based on the classic imitation dynamics (Hofbauer and Sigmund, 1998, Evolutionary Games and Population Dynamics, Cambridge University Press), the imitation dynamics with time delay is investigated, where the probability that an individual will imitate its opponent's own strategy is assumed to depend on the comparison between the past expected payoff of this individual's own strategy and the past expected payoff of its opponent's own strategy, i.e. there is a time delay effect. For the two-phenotype model, we show that if the system has an interior equilibrium and this interior equilibrium is stable when there is no time delay, then there must be a critical value of time delay such that the system tends to a stable periodic solution when the time delay is larger than the critical value. On the other hand, for three-phenotype (rock-scissors-paper) model, the numerical analysis shows that for the stable periodic solution induced by the time delay, the amplitude and the period will increase with the increase of the time delay. These results should help to understand the evolution of behavior based on the imitation dynamics with time delay.

A simple rule of direct reciprocity leads to the stable coexistence of cooperation and defection in the Prisoner's Dilemma game.

The long-term coexistence of cooperation and defection is a common phenomenon in nature and human society. However, none of the theoretical models based on the Prisoner's Dilemma (PD) game can provide a concise theoretical model to explain what leads to the stable coexistence of cooperation and defection in the long-term even though some rules for promoting cooperation have been summarized (Nowak, 2006, Science 314, 1560-1563). Here, based on the concept of direct reciprocity, we develop an elementary model to show why stable coexistence of cooperation and defection in the PD game is possible. The basic idea behind our theoretical model is that all players in a PD game prefer a cooperator as an opponent, and our results show that considering strategies allowing opting out against defection provide a general and concise way of understanding the fundamental importance of direct reciprocity in driving the evolution of cooperation.

Diterpenoid tanshinones inhibit gastric cancer angiogenesis through the PI3K/Akt/mTOR signaling pathway.

ETHNOPHARMACOLOGICAL RELEVANCE: Salvia miltiorrhiza Bunge is a kind of Chinese herbal medicine known for activating blood circulation and removing blood stasis, with the effect of cooling blood and eliminating carbuncles, and has been proven to have the effect of treating tumors. However, the inhibitory effect of Salvia miltiorrhiza Bunge extracts (Diterpenoid tanshinones) on tumors by inhibiting angiogenesis has not been studied in detail. AIM OF THE STUDY: This study aimed to investigate the anti-gastric cancer effect of diterpenoid tanshinones (DT) on angiogenesis, including the therapeutic effects and pathways. MATERIALS AND METHODS: This experiment utilized network pharmacology was used to identify relevant targets and pathways of Salvia miltiorrhiza Bunge-related components in the treatment of gastric cancer. The effects of DT on the proliferation and migration of human gastric cancer cell line SGC-7901 and human umbilical vein endothelial cell line HUVECs were evaluated, and changes in the expression of angiogenesis-related factors were measured. In vivo, experiments were conducted on nude mice to determine tumor activity, size, immunohistochemistry, and related proteins. RESULTS: The findings showed that DT could inhibit the development of gastric cancer by suppressing the proliferation of gastric cancer cells, inducing apoptosis, and inhibiting invasion and metastasis. In addition, the content of angiogenesis-related factors and proteins was significantly altered in DT-affected cells and animals. CONCLUSIONS: Results suggest that DT has potential as a therapeutic agent for the treatment of gastric cancer, as it can inhibit tumor growth and angiogenesis. It was also found that DT may affect the expression of the angiogenic factor VEGF through the PI3K/Akt/mTOR pathway, leading to the regulation of tumor angiogenesis. This study provides a new approach to the development of anti-tumor agents and has significant theoretical and clinical implications for the treatment of gastric cancer.

Jeans and language: kin networks and reproductive success are associated with the adoption of outgroup norms.

Traditional norms of human societies in rural China may have changed owing to population expansion, rapid development of the tourism economy and globalization since the 1990s; people from different ethnic groups might adopt cultural traits from outside their group or lose their own culture at different rates. Human behavioural ecology can help to explain adoption of outgroup cultural values. We compared the adoption of four cultural values, specifically speaking outgroup languages/mother tongue and wearing jeans, in two co-residing ethnic groups, the Mosuo and Han. Both groups are learning outgroup traits, including each other's languages through contact in economic activities, education and kin networks, but only the Mosuo are starting to lose their own language. Males are more likely to adopt outgroup values than females in both groups. Females of the two groups are no different in speaking Mandarin and wearing jeans, whereas males do differ, with Mosuo males being keener to adopt them than Han males. The reason might be that Mosuo men experience more reproductive competition over mates, as Mosuo men have larger reproductive skew than others. Moreover, Mosuo men but not others gain fitness benefits from the adoption of Mandarin (they start reproducing earlier than non-speakers). This article is part of the theme issue 'Social norm change: drivers and consequences'.

Hesitate between confocal laser endomicroscopy and narrow-band imaging: how to choose a better method in the detection of focal precancerous state of gastric cancer.

BACKGROUND: With a high incidence globally, deaths form gastric cancer (GC) are not rare. Early diagnosis is crucial to ameliorate its prognosis. Confocal laser endomicroscopy (CLE) and narrow band imaging (NBI) have been extensively applied in gastroscopy, particularly when it comes to the detection and management of premalignant gastric lesion. Our meta-analysis intends to appraise the diagnostic capability and compare the efficacy of NBI and CLE for focal precancerous state of gastric cancer. METHODS: We performed a literature search up to November 5, 2020 in online databases and major conferences. Two investigators assessed the methodological bias by QUADAS-2, followed by sophisticated study selection and data exaction to make a comparison between sensitivity, specificity, positive and negative likelihood values, and diagnostic odds ratio. A symmetric summary receiver-operating curve (sROC) and its area under the curve (AUC) were used to estimate threshold effect. Additionally, we evaluated the publication bias by Deeks' asymmetry test. RESULTS AND CONCLUSIONS: Four studies involved 248 patients and 526 lesions. In analysis drawn from every lesion, the NBI's pooled sensitivity and specificity were 87% (95% CI: 0.80-0.92) and 85% (95% CI: 0.75-0.91), and those of CLE were 90% (95% CI: 0.85-0.91) and 87% (95% CI: 0.83-0.91). CLE illustrated that the pooled two were slightly higher than NBI when compared at the level of every lesion. The AUC for NBI and CLE was 0.92 (0.90-0.94) and 0.95 (0.92-0.96), and there might be a threshold effect, according to the shoulder-like distribution of scatter points in the sROC. We did not find obvious publication bias in our meta-analysis.

Variation of soil microbial carbon use efficiency (CUE) and its Influence mechanism in the context of global environmental change: a review.

Soil microbial carbon utilization efficiency (CUE) is the efficiency with which microorganisms convert absorbed carbon (C) into their own biomass C, also referred to as microorganism growth efficiency. Soil microbial CUE is a critical physiological and ecological parameter in the ecosystem's C cycle, influencing the processes of C retention, turnover, soil mineralization, and greenhouse gas emission. Understanding the variation of soil microbial CUE and its influence mechanism in the context of global environmental change is critical for a better understanding of the ecosystem's C cycle process and its response to global changes. In this review, the definition of CUE and its measurement methods are reviewed, and the research progress of soil microbial CUE variation and influencing factors is primarily reviewed and analyzed. Soil microbial CUE is usually expressed as the ratio of microbial growth and absorption, which is divided into methods based on the microbial growth rate, microbial biomass, substrate absorption rate, and substrate concentration change, and varies from 0.2 to 0.8. Thermodynamics, ecological environmental factors, substrate nutrient quality and availability, stoichiometric balance, and microbial community composition all influence this variation. In the future, soil microbial CUE research should focus on quantitative analysis of trace metabolic components, analysis of the regulation mechanism of biological-environmental interactions, and optimization of the carbon cycle model of microorganisms' dynamic physiological response process.

Land-use change influence soil quality parameters at an ecologically fragile area of YongDeng County of Gansu Province, China.

Dry ecosystems, despite their relative levels of aridity, are very diverse, and play a vital role in the livelihoods of many dryland inhabitants. It is therefore critical to investigate the relationship between land-use change and soil quality parameters to offer a scientific basis for optimizing land-use planning and improving soil quality status in dry ecosystems and ecologically vulnerable areas. This study, therefore, analyzed the physicochemical properties of soils in five different land-use types namely farmland, abandoned farmland, natural grassland, artificial lemon forest, and poplar woodland at YongDeng County. The soil quality status of the aforementioned land-use types was also evaluated through Principal component analysis. The results revealed that abandoned farmland and natural grassland recorded the highest average values of soil coarse particles of 24.0% and 23.4% respectively compared to the other land-use types. The highest average value (46.1%) of fine soil particles was recorded in poplar woodland followed by natural grassland (36.6%) and the average value of very fine soil particles was higher in farmland (40.8%) and artificial lemon woodland (38.3%) than in the other land-use types. The average value of clayey particles was highest in farmland (11.1%), followed by artificial lemon woodland (9.3%), and abandoned farmland (6.5%), then poplar woodland which recorded an average value of (4.2%). The average values of Soil water content, soil pH, soil electrical conductivity, and soil total nitrogen content were significantly higher in farmland compared to the other land-use types. Soil organic carbon content was significantly higher in abandoned farmland at (P < 0.03) and lemon woodland at (P < 0.01) than in farmlands, natural grasslands, and poplar stands. The soil quality indicators of the different land-use types were significantly correlated with each other. Among them, the correlation coefficient of each evaluation index was highest in poplar woodland, followed by natural grassland, lower in farmland and artificial lemon woodland, and lowest in abandoned farmland. The overall soil quality scores were in the following order: farmland > abandoned farmland > 0 > grassland > lemon woodland > poplar woodland. In the study area, the soil quality of farmland that has been finely managed and naturally restored to grassland following abandonment is superior, whereas the soil quality of natural grassland, artificial lemon woodland, and poplar forest land is substandard. The comprehensive analysis of soil quality demonstrates that conservation tillage and fine management of water-irrigated farmland, as well as the natural conversion of abandoned farmland to grassland, can significantly improve the soil quality of sandy soils, reduce water and soil loss, increase fertility, and gradually improve regional ecological environmental conditions.