Evolutionary dynamics in financial markets with heterogeneities in investment strategies and reference points.

In nature and human societies, the effects of homogeneous and heterogeneous characteristics on the evolution of collective behaviors are quite different from each other. By incorporating pair pattern strategies and reference point strategies into an agent-based model, we have investigated the effects of homogeneous and heterogeneous investment strategies and reference points on price movement. In the market flooded with the investors with homogeneous investment strategies or homogeneous reference points, large price fluctuations occur. In the market flooded with the investors with heterogeneous investment strategies or heterogeneous reference points, moderate price fluctuations occur. The coexistence of different kinds of investment strategies can not only refrain from the occurrence of large price fluctuations but also the occurrence of no-trading states. The present model reveals that the coexistence of heterogeneous populations, whether they are the individuals with heterogeneous investment strategies or heterogeneous reference points of stock prices, is an important factor for the stability of the stock market.

Factors Influencing Trace Element Levels in the Blood of Tin Smelting Workers.

BACKGROUND: This study is to assess the correlation between blood concentration ranges of eight elements of tin smelting workers from Guangxi Liuzhou and their job type, working years, age, and sex. METHODS: We collected blood samples of 218 tin smelting workers from a Chinese tin smelting factory and determined the levels of elements by inductively coupled plasma mass spectrometry. RESULTS: Within the blood concentrations of eight metal elements of the objects, the blood concentration of copper and zinc is affected by the job type of comprehensive work; that of arsenic and mercury is affected by refining; and that of chromium, cadmium, and lead is affected by primary smelting. CONCLUSIONS: We present the remarkable influence of four job types on the blood concentration of seven trace elements.

Market impact shapes competitive advantage of investment strategies in financial markets.

The formation of an efficient market depends on the competition between different investment strategies, which accelerates all available information into asset prices. By incorporating market impact and two kinds of investment strategies into an agent-based model, we have investigated the coevolutionary mechanism of different investment strategies and the role of market impact in shaping a competitive advantage in financial markets. The coevolution of history-dependent strategies and reference point strategies depends on the levels of market impact and risk tolerance. For low market impact and low risk tolerance, the majority-win effect makes the trend-following strategies become dominant strategies. For high market impact and low risk tolerance, the minority-win effect makes the trend-rejecting strategies coupled with trend-following strategies become dominant strategies. The coupled effects of price fluctuations and strategy distributions have been investigated in depth. A U-shape distribution of history-dependent strategies is beneficial for a stable price, which is destroyed by the existence of reference point strategies with low risk tolerance. A δ-like distribution of history-dependent strategies leads to a large price fluctuation, which is suppressed by the existence of reference point strategies with high risk tolerance. The strategies that earn more in an inefficient market lose more in an efficient market. Such a result gives us another explanation for the principle of risk-profit equilibrium in financial markets: high return in an inefficient market should be coupled with high risk in an efficient market, low return in an inefficient market should be coupled with low risk in an efficient market.

Construction of a ferroptosis scoring system and identification of LINC01572 as a novel ferroptosis suppressor in lung adenocarcinoma.

Background: Ferroptosis is a novel process of programmed cell death driven by excessive lipid peroxidation that is associated with the development of lung adenocarcinoma. N6-methyladenosine (m6a) modification of multiple genes is involved in regulating the ferroptosis process, while the predictive value of N6-methyladenosine- and ferroptosis-associated lncRNA (FMRlncRNA) in the prognosis of patients remains with LUAD remains unknown. Methods: Unsupervised cluster algorithm was applied to generate subcluster in LUAD according to ferroptosis-associated lncRNA. Stepwise Cox analysis and LASSO algorithm were applied to develop a prognostic model. Cellular location was detected by single-cell analysis. Also, we conducted Gene set enrichment analysis (GSEA) enrichment, immune microenvironment and drug sensitivity analysis. In addition, the expression and function of the LINC01572 were investigated by several in vitro experiments including qRT-PCR, cell viability assays and ferroptosis assays. Results: A novel ferroptosis-associated lncRNAs-based molecular subtype containing two subclusters were determined in LUAD. Then, we successfully created a risk model according to five ferroptosis-associated lncRNAs (LINC00472, MBNL1-AS1, LINC01572, ZFPM2-AS1, and TMPO-AS1). Our nominated model had good stability and predictive function. The expression patterns of five ferroptosis-associated lncRNAs were confirmed by polymerase chain reaction (PCR) in LUAD cell lines. Knockdown of LINC01572 significantly inhibited cell viability and induced ferroptosis in LUAD cell lines. Conclusion: Our data provided a risk score system based on ferroptosis-associated lncRNAs with prognostic value in LUAD. Moreover, LINC01572 may serve as a novel ferroptosis suppressor in LUAD.

Correlation between CYP1A1 polymorphisms and susceptibility to glyphosate-induced reduction of serum cholinesterase: A case-control study of a Chinese population.

Glyphosate (GLP) is one of the most common herbicides worldwide. The serum cholinesterase (ChE) may be affected when exposed to glyphosate. Reduction of serum ChE by herbicides is probably related to cytochrome P450 (CYP450) family polymorphisms. We suspect that the abnormal ChE caused by GLP could be correlated with the CYP family members. To determine whether CYP1B1 (rs1056827 and rs1056836) and CYP1A1 (rs1048943) gene polymorphisms and individual susceptibility to GLP-induced ChE abnormalities were interrelated in the Chinese Han population, we performed this genetic association study on a total of 230 workers previously exposed to GLP, including 115 cases with reduced serum ChE and 115 controls with normal serum ChE. Two even groups of cases and controls were enrolled. The CYP1A1 and CYP1B1 polymorphisms in both groups were genotyped using TaqMan. Subjects with the CYP1A1 rs619586 genotypes showed an increased risk of GLP-induced reduction of serum ChE, which was more evident in the following subgroups: female, > 35 years old, history of GLP exposure time <10 years and >10 years, nonsmoker and nondrinker. The results show that CYP1A1 rs619586 was significantly associated with the GLP-induced reduction in serum ChE and could be a biomarker of susceptibility for Chinese GLP exposed workers. Because of a large number of people exposed to glyphosate, this study has a significance in protecting their health.

Circadian misalignment alters insulin sensitivity during the light phase and shifts glucose tolerance rhythms in female mice.

Shift work and jet lag, characterized by circadian misalignment, can disrupt several physiological activities, but whether they affect the rhythm of glucose uptake and insulin sensitivity remain unclear. In the present study, female C57BL/6J mice were maintained for four weeks under the condition of 8-hour phase advance and delay every 3-4 days to mimic shift work. Intraperitoneal glucose tolerance test (IPGTT) and intraperitoneal insulin tolerance test (IPITT) were performed repeatedly at Zeitgeber time (ZT) 0, ZT6, ZT12, and ZT18. Glucose-stimulated insulin secretion (GSIS) test was performed at ZT6. We found that the average level of daily glucose tolerance did not decrease but the phase of glucose tolerance advanced by 2.27 hours and the amplitude attenuated by 20.4% in shift work mice. At ZT6, IPITT showed blood glucose at 30 min after insulin injection decreased faster in shift work mice (-3.50±0.74mmol/L, -61.58±7.89%) than that in control mice (-2.11±1.10mmol/L, -33.72±17.24%), but IPGTT and GSIS test showed no significant difference between the two groups. Food intake monitor showed that the feeding time of shift work mice continued to advance. Restricting feed to a fixed 12-hour period alleviated the increase of insulin sensitivity induced by shift-work. We also observed that an increase of blood glucose and liver glycogen at ZT0, as well as a phase advance of liver clock genes and some glucose metabolism-related genes such as forkhead box O1 (Foxo1) and peroxisome proliferator activated receptor alpha (Pparα) in shift work mice. Our results showed that light change-simulated shift work altered insulin sensitivity during the light phase and shifted glucose tolerance rhythms in female mice, suggesting a causal association between long-term shift work and type 2 diabetes.

Development and validation of a nomogram to predict liver metastasis in patients with pancreatic ductal adenocarcinoma: a large cohort study.

Background: Few studies have explored the relationship between clinicopathological factors of patients with pancreatic ductal adenocarcinoma (PDAC) and liver metastasis. The aim of this study was to develop and validate a nomogram to predict liver metastasis in patients with PDAC. Patients and methods: Patients diagnosed with PDAC between 2004 and 2015 from the Surveillance, Epidemiology, and End Results (SEER) database were retrospectively collected. The nomogram was established based on a logistic regression model. The precision of the nomogram was evaluated and compared using concordance index (C-index), and the area under receiver operating characteristic curve (AUC). The clinical use of nomogram was evaluated by making use of a decision curve analysis (DCA). Results: A total of 12,644 eligible patients, which were randomly divided into training (n=9,483) and validation cohorts (n=3,161), were included in this study. The nomograms, which were established on the basis of independent predictors, were well calibrated, and demonstrated good discriminative ability, with C-indexes of 0.784 for the training cohort and 0.790 for validation cohort. The values of AUC for training and validation cohort were 0.792 and 0.800, respectively. When other sites of distant metastases were included into this predictive system, the new predictive model demonstrated a better discriminative ability and greater net benefit in predicting liver metastasis in patients with PDAC in both the training and validation cohorts. Conclusion: Nomograms were constructed to predict liver metastasis in patients with PDAC. Validation revealed excellent discrimination and calibration of the nomograms, suggesting that the nomograms were well calibrated and could serve to improve the prediction of the risks of liver metastasis which can be used to guide the management of patients with PDAC.

MiR-92a and miR-486 are potential diagnostic biomarkers for mercury poisoning and jointly sustain NF-κB activity in mercury toxicity.

Occupational and environmental exposure to mercury is a public health concern worldwide. Although the altered epigenetic regulatory features, such as microRNA, have been associated with mercury exposure, the underlying molecular mechanism is not well illuminated. This study aimed to confirm that hsa-miR-92a and hsa-miR-486 are novel diagnostic biomarkers of occupational mercury poisoning, and to explore the underlying mechanism of miR-92a and miR-486 in mercury toxicity. RT-qPCR assays and receiver operating characteristics curve analyses were conducted to confirm the diagnostic value of miR-92a and miR-486 as biomarkers of occupational mercury poisoning. Dual-luciferase assay was applied to confirm the target gene of miR-92a and miR-486 in vitro. Then, we established an in-vitro model where miR-92a and miR-486 were overexpressed or knocked down in HEK-293 and HUVEC cells. RT-qPCR and western blotting were used to analyze gene and protein expression levels. Cell apoptosis was determined by flow cytometry. Results show that miR-92a and miR-486 expression levels were up-regulated in workers exposed to occupational mercury. Upregulation of miR-92a and miR-486 may play a crucial role in mercury toxicity by jointly activating the NF-κB signaling pathway via targeting KLF4 and Cezanne, respectively.

Identification of differential plasma miRNA profiles in Chinese workers with occupational lead exposure.

Elevated lead absorptions are hazardous factors in lead-related workers. Previous studies have found its toxic impacts on nervous, circulatory, and metabolic systems. We hypothesized that alteration of miRNAs profile in plasma was closely associated with lead exposure. We analyzed to identify lead-related miRNAs in workers occupationally exposed to lead. Microarray assay was performed to detect plasma miRNA between workers with high and minimal lead exposure in the discovery stage. The following prediction of miRNAs' candidate target genes was carried out by using miRecords, STRING, and KEGG databases. We finally identified four miRNAs significantly associated with high level of blood lead. miR-520c-3p (*P=0.014), miR-211 (*P=0.019), and miR-148a (*P=0.031) were downexpressed in workers with high lead exposure and with high blood lead level (BLL), while miR-572(*P=0.027) displayed an opposite profile. Functional analysis of miRNAs displayed that these miRNAs could trigger different cellular genes and pathways. People under chronic lead exposure had a diverse 'fingerprint' plasma miRNA profile. Our study suggested that miR-520c-3p, miR-211, miR-148a, and miR-572 were the potential biomarkers for lead susceptibility in Chinese.

The Association of Telomere Length in Peripheral Blood Cells with Cancer Risk: A Systematic Review and Meta-analysis of Prospective Studies.

The association between telomere length (TL) in peripheral blood cells and cancer risk remains inconclusive. We carried out a meta-analysis on prospective studies. The study-specific RR estimates were first transformed to a common comparable scale and then were pooled by a random-effects model. The dataset was composed of 13,894 cases and 71,672 controls from 28 studies in 25 articles. In the comparison of the longest versus shortest third of TL, we observed a marginally positive association between longer TL and higher risk of total cancers [OR = 1.086; 95% confidence interval (CI), 0.952-1.238]. Subgroup analyses showed that the association was stronger in lung cancer (n = 3; OR = 1.690; 95% CI, 1.253-2.280), in men (n = 6; OR = 1.302; 95% CI, 1.120-1.514) and in studies with more precise methods for DNA extraction (phenol-chloroform, salting-out or magnetic bead, n = 6, OR = 1.618; 95% CI, 1.320-1.985) and TL measurement (multiplex Q-PCR, n = 8; OR = 1.439; 95% CI, 1.118-1.852). Our meta-analysis suggested longer TL in peripheral blood cells is a likely risk factor for lung cancer or cancers in men. Accurate DNA extraction and TL measurement methods make it more liable to find significant associations between TL and cancer risk and thus should be taken into consideration in future epidemiologic studies. Cancer Epidemiol Biomarkers Prev; 26(9); 1381-90. ©2017 AACR.

Dynamic Portfolio Strategy Using Clustering Approach.

The problem of portfolio optimization is one of the most important issues in asset management. We here propose a new dynamic portfolio strategy based on the time-varying structures of MST networks in Chinese stock markets, where the market condition is further considered when using the optimal portfolios for investment. A portfolio strategy comprises two stages: First, select the portfolios by choosing central and peripheral stocks in the selection horizon using five topological parameters, namely degree, betweenness centrality, distance on degree criterion, distance on correlation criterion and distance on distance criterion. Second, use the portfolios for investment in the investment horizon. The optimal portfolio is chosen by comparing central and peripheral portfolios under different combinations of market conditions in the selection and investment horizons. Market conditions in our paper are identified by the ratios of the number of trading days with rising index to the total number of trading days, or the sum of the amplitudes of the trading days with rising index to the sum of the amplitudes of the total trading days. We find that central portfolios outperform peripheral portfolios when the market is under a drawup condition, or when the market is stable or drawup in the selection horizon and is under a stable condition in the investment horizon. We also find that peripheral portfolios gain more than central portfolios when the market is stable in the selection horizon and is drawdown in the investment horizon. Empirical tests are carried out based on the optimal portfolio strategy. Among all possible optimal portfolio strategies based on different parameters to select portfolios and different criteria to identify market conditions, 65% of our optimal portfolio strategies outperform the random strategy for the Shanghai A-Share market while the proportion is 70% for the Shenzhen A-Share market.

Biomimetic gelatin methacrylamide hydrogel scaffolds for bone tissue engineering.

Bone tissue engineering is an exciting research area that develops functional strategies for the most challenging bone related clinical issues. Among the numerous materials used in this area, biomimetic materials have been developed amazingly over the past decades. In this study, biomimetic gelatin methacrylamide (Bio-GelMA) hydrogel scaffolds have been fabricated to mimic both the physical architecture and chemical composition of the natural bone extracellular matrix (ECM) by using the thermally induced phase separation (TIPS) technique, to provide three-dimensional templates and extracellular matrix microenvironments. Adipose derived stem cells (ADSCs) also play a pivotal role in osteogenesis when co-cultured with Bio-GelMA at days 7, 14, and 21. The effects of cell-biomaterial interactions such as adhesion, proliferation, and osteogenic differentiation were systematically investigated. The results showed that Bio-GelMA significantly enhanced cell attachment and viability, alkaline phosphatase (ALP) activity, and mineral deposition, as well as mRNA expression levels of osteogenic genes of ADSCs. In a subcutaneous model, H&E staining and dual immunofluorescent staining differed significantly. More importantly, in a critical-size rat calvarial bone defect model, the results of Micro-CT, H&E staining and Masson trichrome staining confirmed that the combination of the Bio-GelMA and ADSCs could enhance osteogenesis significantly. Altogether, the observations prove that the Bio-GelMA scaffolds can act as cell carriers for ADSCs, promote greater osteogenic differentiation of ADSCs and may have great potential in future clinical applications.

Coupled effects of local movement and global interaction on contagion.

By incorporating segregated spatial domain and individual-based linkage into the SIS (susceptible-infected-susceptible) model, we propose a generalized epidemic model which can change from the territorial epidemic model to the networked epidemic model. The role of the individual-based linkage between different spatial domains is investigated. As we adjust the timescale parameter τ from 0 to unity, which represents the degree of activation of the individual-based linkage, three regions are found. Within the region of 0 < τ < 0.02 , the epidemic is determined by local movement and is sensitive to the timescale τ . Within the region of 0.02 < τ < 0.5 , the epidemic is insensitive to the timescale τ . Within the region of 0.5 < τ < 1 , the outbreak of the epidemic is determined by the structure of the individual-based linkage. As we keep an eye on the first region, the role of activating the individual-based linkage in the present model is similar to the role of the shortcuts in the two-dimensional small world network. Only activating a small number of the individual-based linkage can prompt the outbreak of the epidemic globally. The role of narrowing segregated spatial domain and reducing mobility in epidemic control is checked. These two measures are found to be conducive to curbing the spread of infectious disease only when the global interaction is suppressed. A log-log relation between the change in the number of infected individuals and the timescale τ is found. By calculating the epidemic threshold and the mean first encounter time, we heuristically analyze the microscopic characteristics of the propagation of the epidemic in the present model.

Effects of contrarians in the minority game.

We study the effects of the presence of contrarians in an agent-based model of competing populations. Contrarians are common in societies. These contrarians are agents who deliberately prefer to hold an opinion that is contrary to the prevailing idea of the commons or normal agents. Contrarians are introduced within the context of the minority game (MG), which is a binary model for an evolving and adaptive population of agents competing for a limited resource. The average success rate among the agents is found to have a nonmonotonic dependence on the fraction a(c) of contrarians. For small a(c), the contrarians systematically outperform the normal agents by avoiding the crowd effect and enhance the overall success rate. For high a(c), the anti-persistent nature of the MG is disturbed and the few normal agents outperform the contrarians. Qualitative discussion and analytic results for the small a(c) and high a(c) regimes are presented, and the crossover behavior between the two regimes is discussed.