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Compared to previous studies that generally detect scientific breakthroughs based on citation patterns, this article proposes a knowledge entity‐based disruption indicator by quantifying the change of knowledge directly created and inspired by scientific breakthroughs to their evolutionary trajectories. Two groups of analytic units, including MeSH terms and their co‐occurrences, are employed independently by the indicator to measure the change of knowledge. The effectiveness of the proposed indicators was evaluated against the four datasets of scientific breakthroughs derived from four recognition trials. In terms of identifying scientific breakthroughs, the proposed disruption indicator based on MeSH co‐occurrences outperforms that based on MeSH terms and three earlier citation‐based disruption indicators. It is also shown that in our indicator, measuring the change of knowledge inspired by the focal paper in its evolutionary trajectory is a larger contributor than measuring the change created by the focal paper. Our study not only offers empirical insights into conceptual understanding of scientific breakthroughs but also provides practical disruption indicator for scientists and science management agencies searching for valuable research. [ABSTRACT FROM AUTHOR]

In this paper, we present several new upper bounds for the infinity norm of the inverse of Nekrasov matrices by using scaling matrices with two values on their diagonals, which improve the corresponding results of Gao et al. and Kolotilina. Numerical examples and comparisons with the existing bounds are included. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to compare the causal effect of overall obesity and abdominal obesity on type 2 diabetes among Chinese Han individuals.Methods: The causal relationship of BMI and waist-to-hip ratio (WHR) with the risk of glucose deterioration and glycemic traits was compared using two different genetic instruments based on 30 BMI loci and 6 WHR loci with Mendelian randomization (MR) in three prospective cohorts (n = 6,476).Results: Each 1-SD genetically instrumented higher WHR was associated with a 65.7% higher risk of glucose deterioration (95% CI = 1.069-2.569, P = 0.024), whereas no significant association of BMI with glucose deterioration was observed. Furthermore, a causal relationship was found only between BMI and homeostatic model assessment β-cell function (HOMA-B) (β = 0.143, P = 0.001), and there was a nominal association with Stumvoll second-phase insulin secretion traits (β = 0.074, P = 0.022). The significance level did not persist in sensitivity analyses, except in the causal estimate of WHR on the Gutt index in MR-Egger (β = -0.379, P = 0.022) and the causal estimate of BMI on homeostatic model assessment β-cell function in weighted median MR (β = 0.128, P = 0.017).Conclusions: The data from this study support the potential causal relationship between abdominal obesity and hyperglycemia, which may be driven by aggravated insulin resistance, in contrast with the potential causal relationship between overall obesity and insulin secretion. [ABSTRACT FROM AUTHOR]

Irisin is a novel hormone secreted by skeletal muscle after exercise, which may ameliorate insulin resistance. In this study, we aimed to explore the relationship between circulating irisin levels and type 2 diabetes mellitus (T2DM) as well as related metabolic traits in a Chinese population. A total of 203 subjects were recruited. Of these, 68 subjects with normal glucose tolerance (NGT), 63 subjects with impaired glucose regulation (IGR) and 72 subjects with new-onset T2DM. Circulating irisin levels were measured by enzyme-linked immunosorbent assay (ELISA). Detailed clinical investigations and biochemistry measurements were carried out in all of the subjects. Multivariate linear regression analysis was performed to assess the association between irisin levels and related metabolic characteristics. All subjects were classified into normal weight and overweight/obese subgroups according to body mass index (BMI). No significant differences in circulating irisin levels were identified among the three groups ( P = 0.9741). After adjusting for covariates, multiple linear regression analysis revealed that serum irisin level was independently and significantly associated with total cholesterol ( P = 0.0005), low-density lipoprotein cholesterol ( P = 0.0014), fasting fatty acids ( P = 0.0402) and uric acid ( P = 0.0062). By dividing the serum irisin levels into three tertile groups, the values of total cholesterol, low-density lipoprotein cholesterol, fasting fatty acids and uric acid were all increased significantly with the increase of irisin ( P < 0.05). Moreover, serum irisin levels remain closely related to total cholesterol in both normal weight and overweight/obese subgroups. Our study suggests that circulating irisin concentrations are significantly associated with lipid and uric acid metabolism in a Chinese population. [ABSTRACT FROM AUTHOR]

SUMMARY This paper examines how market microstructure variables can be used to forecast foreign exchange (FX) rates at frequencies of one to several minutes. We use a unique FX dataset of global inter-dealer electronic transactions and applied the artificial neural network (ANN) as the predicting model. The immediately preceding bid and ask prices are significant factors in these predictions, which is in keeping with market microstructure theory. These microstructure factors have not been tested in an ANN model before. High-frequency trading strategies based on the ANN model are shown to be profitable even when transaction costs are included. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The article discusses a study which analyzed whether genetic variants of FNDC5 were associated with diabetic microvascular complications in Chinese population. Topics include other factors that contribute to the progression of diabetic complications, the approval of the study by the institution review board of the Shanghai Jiao Tong University Affiliated Sixth People's Hospital in accordance with Helsinki Declaration II principles, and the association between irisin and diabetic retinopathy.