Are Smell-Based Metrics Actually Useful in Effort-Aware Structural Change-Proneness Prediction? An Empirical Study

Bad code smells (also named as code smells) are symptoms of poor design choices in implementation. Existing studies empirically confirmed that the presence of code smells increases the likelihood of subsequent changes (i.e., change-proness). However, to the best of our knowledge, no prior studies have leveraged smell-based metrics to predict particular change type (i.e., structural changes). Moreover, when evaluating the effectiveness of smell-based metrics in structural change-proneness prediction, none of existing studies take into account of the effort inspecting those change-prone source code. In this paper, we consider five smell-based metrics for effort-aware structural change-proneness prediction and compare these metrics with a baseline of well-known CK metrics in predicting particular categories of change types. Specifically, we first employ univariate logistic regression to analyze the correlation between each smellbased metric and structural change-proneness. Then, we build multivariate prediction models to examine the effectiveness of smell-based metrics in effort-aware structural change-proneness prediction when used alone and used together with the baseline metrics, respectively. Our experiments are conducted on six Java open-source projects with up to 60 versions and results indicate that: (1) all smell-based metrics are significantly related to structural change-proneness, except metric ANS in hive and SCM in camel after removing confounding effect of file size; (2) in most cases, smell-based metrics outperform the baseline metrics in predicting structural change-proneness; and (3) when used together with the baseline metrics, the smell-based metrics are more effective to predict change-prone files with being aware of inspection effort

Cdc42 is essential for the polarized movement and adhesion of human dental pulp stem cells

Objective: Stem cell-based tissue repair and regeneration require the regulation of cell migration and adhesion. As a regulator of cell polarization, Cdc42 (cell division control protein 42) plays a basic role at the initial stage of cell migration and adhesion. This study explores the effect of Cdc42 on the polarized migration and adhesion of hDPSCs (human dental pulp stem cells). Design: HDPSCs were isolated from extracted third molars and transfected with siRNA targeted against Cdc42. Scratch wound assays and transwell assays were performed to detect the migration of human dental pulp stem cells. Polarization assays were applied to explore the polarized movement of Golgi bodies and nuclei. Western blot was used to examine the expression of related proteins. Results: The expression of Cdc42 was knocked down by siRNA transfection, which inhibited the migration of hDPSCs in both the scratch wound assays and transwell assays. Meanwhile, the proportion of polarized hDPSCs during migration was also decreased, and the adhesion ability of hDPSCs was downregulated. Western blot demonstrated that these effects were dependent on FAK (focal adhesion kinase), β-catenin and GSK3β (Glycogen synthase kinase-3β). Conclusion Our study demonstrates that Cdc42 plays an essential role during the polarized movement and adhesion of hDPSCs

Genome-wide Association Study (GWAS) of mesocotyl elongation based on re-sequencing approach in rice

Annotation of candidate genes anchored by associated SNPs. (XLSX 34 kb

JOT-CREDIT PROBLEMS OF RURAL CREDIT COOPERATIVE AND SUGGESTIONS: THE CASE OF XIN LE COUNTRY, SHIJIAZHUANG CITY, HEBEIPROVINCE, CHINA

The rural credit cooperative is an important part of financial system in China. The jot credit provided by rural credit cooperative serves as an important financial tool for its members. The reformation of rural credit cooperatives on 2014 has further strengthened the important of jot credit in Hebei province, China. However, there are problems in the jot credit as shown by the increasing income gap between the rich and poor. This warrants a study to unveil the problem of rural credit cooperative’s jot credit and suggestions to improve the jot credit. Using the case of Xin le Shijiazhuang, Hebei province, this paper aims to explore the rural credit cooperative’s jot credit problem and suggest potential solutions. Results reveal that there are high demand for loan among the peasants. However, the tedious application procedure, rigidity in the duration and terms of loan, are the problems that discouraging jot credit usage among the peasants. It is suggested that the scope of service, duration and terms of loan to be expanded to meet the diverse needs of peasants. In addition, the nimble rate should be implemented on the jot credit by stages. The jot credit is the new direction of the credit business development. Peasants have high enthusiasm in repayment and the non-performing loan is in a downward trend. Meanwhile the jot credit, to certain extent, still has some problems to be tackled.Keywords: Rural Credit Cooperative; Jot-Credit Problems; Xin Le Country

Theoretical Study on Superradiant Raman Scattering with Rubidium Atoms in An Optical Cavity

Superradiant Raman scattering of Rubidium atoms has been explored in the experiment [Nature 484, 78 (2012)] to prove the concept of the superradiant laser, which attracts significant attentions in quantum metrology due to the expected ultra-narrow linewidth down to millihertz. To better understand the physics involved in this experiment, we have developed a quantum master equation theory by treating the Rubidium atoms as three-level systems, and coupling them with a dressed laser and an optical cavity. Our simulations show different superradiant Raman scattering pulses for the systems within the crossover and strong coupling regime, and the shifted and broader spectrum of the steady-state Raman scattering. Thus, our studies provide a unified view on the superradiant Raman scattering pulses, and an alternative explanation to the broad spectrum of the steady-state Raman scattering, as observed in the experiment. In future, our theory can be readily applied to study other interesting phenomena relying on the superradiant Raman scattering, such as magnetic field sensing, real-time tracking of quantum phase, Dicke phase transition of non-equilibrium dynamics and so on.Comment: 9 pages, 11 figure