Stack Overflow in Github: Any Snippets There?

When programmers look for how to achieve certain programming tasks, Stack Overflow is a popular destination in search engine results. Over the years, Stack Overflow has accumulated an impressive knowledge base of snippets of code that are amply documented. We are interested in studying how programmers use these snippets of code in their projects. Can we find Stack Overflow snippets in real projects? When snippets are used, is this copy literal or does it suffer adaptations? And are these adaptations specializations required by the idiosyncrasies of the target artifact, or are they motivated by specific requirements of the programmer? The large-scale study presented on this paper analyzes 909k non-fork Python projects hosted on Github, which contain 290M function definitions, and 1.9M Python snippets captured in Stack Overflow. Results are presented as quantitative analysis of block-level code cloning intra and inter Stack Overflow and GitHub, and as an analysis of programming behaviors through the qualitative analysis of our findings.Comment: 14th International Conference on Mining Software Repositories, 11 page

Integrated Management of Emergency Vehicle Fleet

The growing public concerns for safety and the advances in traffic management systems, that have made the availability of real-time traffic information a reality, have created an opportunity to build integrated decision support systems that can improve the coordination and sharing of information between agencies that are responsible for public safety and security and transportation agencies to provide more efficient Emergency Response Service. In an Emergency Response System, reduction of the duration of response time can yield substantial benefits. The response time plays a crucial role in minimizing the adverse impacts: fatalities and loss of property can be greatly reduced by reducing the response time for emergencies. In this dissertation, we have developed an integrated model that can assist emergency response fleet dispatchers in managing the fleet. This model can help reduce the response time and improve service level by specifically accounting for the following: Vehicle Deployment: given real-time information about the status of the emergency response fleet, traffic information and the status of emergency calls, select proper fleet assignment schemes that satisfy various operation requirements. Vehicle Routing: given real-time traffic information, provide real-time route guidance for drivers of dispatched vehicles. This goal is achieved by applying various shortest path algorithms into the solution procedure. Planning and Evaluation: given the status of the fleet and the frequency of emergency calls in various areas of a region, the model can help evaluate the performance of the current system and help plan for potential sites for the relocation of vehicles and allocate an appropriate fleet of vehicles to these sites. The vehicle deployment problem is formulated as an integer optimization problem. Since this problem has been shown to be NP-hard and because of the nature of emergency response, we developed heuristics which can provide quality solutions with short computational times. Several test algorithms are proposed to solve the emergency response vehicle deployment problem. Different methods for obtaining lower bounds for the value of objective function are analyzed in this dissertation. To evaluate the performance of the system under various scenarios, a simulation model is developed. The simulation system is calibrated based on real-world data. The results of simulation and analysis show the proposed system can effectively improve the emergency response service level. Application of this model in facility allocation illustrates its usage in other relevant operational scenarios

When poignant stories outweigh cold hard facts: A meta-analysis of the anecdotal bias

The objective of this paper is to resolve mixed findings about which type of evidence is more persuasive—statistical or anecdotal information. In a meta-analysis of 61 papers exploring the persuasive impact of evidence type, we establish that, in situations where emotional engagement is high (e.g., an issue associated with a severe threat, involving a health issue, or affecting oneself), statistical evidence is less influential than anecdotal evidence. However, in situations where emotional engagement is relatively low (e.g., an issue associated with low threat severity, involving a non-health issue, or affecting others), statistical evidence is more persuasive than anecdotal evidence. We discuss the theoretical and practical implications of these findings, and how to improve persuasive messaging by considering the contextual effectiveness of both anecdotes and statistics

MicroRNA-383 located in frequently deleted chromosomal locus 8p22 regulates CD44 in prostate cancer.

A major genomic alteration in prostate cancer (PCa) is frequent loss of chromosome (chr) 8p with a common region of loss of heterozygosity (LOH) at chr8p22 locus. Genomic studies implicate this locus in the initiation of clinically significant PCa and with progression to metastatic disease. However, the genes within this region have not been fully characterized to date. Here we demonstrate for the first time that a microRNA component of this region-miR-383-is frequently downregulated in prostate cancer, has a critical role in determining tumor-initiating potential and is involved in prostate cancer metastasis via direct regulation of CD44, a ubiquitous marker of PCa tumor-initiating cells (TICs)/stem cells. Expression analyses of miR-383 in PCa clinical tissues established that low miR-383 expression is associated with poor prognosis. Functional data suggest that miR-383 regulates PCa tumor-initiating/stem-like cells via CD44 regulation. Ectopic expression of miR-383 inhibited tumor-initiating capacity of CD44+ PCa cells. Also, 'anti-metastatic' effects of ectopic miR-383 expression were observed in a PCa experimental metastasis model. In view of our results, we propose that frequent loss of miR-383 at chr8p22 region leads to tumor initiation and prostate cancer metastasis. Thus, we have identified a novel finding that associates a long observed genomic alteration to PCa stemness and metastasis. Our data suggest that restoration of miR-383 expression may be an effective therapeutic modality against PCa. Importantly, we identified miR-383 as a novel PCa tissue diagnostic biomarker with a potential that outperforms that of serum PSA

The topology of the Fermi surface of Bi2212 from angle resolved photoemission

We present a study of the topology of the normal state Fermi surface (FS) of the high Tc superconductor Bi2212 using angle-resolved photoemission. We present FS mapping experiments, recorded using unpolarised radiation with high (E,k) resolution, and an extremely dense sampling of k-space. In addition, synchrotron radiation-based ARPES has been used to prove the energy independence of the FS as seen by photoemission. We resolve the current controversy regarding the normal state FS in Bi2212. The true picture is simple, self-consistent and robust: the FS is hole-like, with the form of rounded tubes centred on the corners of the Brillouin zone. Two further types of features are also clearly observed: shadow FSs, and diffraction replicas of the main FS caused by passage of the photoelectrons through the modulated Bi-O planes.Comment: M2S-HTSC-VI conference paper (4 pages, 3 eps. figures), using Elsevier style espcrc2.st

Towards Automating Precision Studies of Clone Detectors

Current research in clone detection suffers from poor ecosystems for evaluating precision of clone detection tools. Corpora of labeled clones are scarce and incomplete, making evaluation labor intensive and idiosyncratic, and limiting inter tool comparison. Precision-assessment tools are simply lacking. We present a semi-automated approach to facilitate precision studies of clone detection tools. The approach merges automatic mechanisms of clone classification with manual validation of clone pairs. We demonstrate that the proposed automatic approach has a very high precision and it significantly reduces the number of clone pairs that need human validation during precision experiments. Moreover, we aggregate the individual effort of multiple teams into a single evolving dataset of labeled clone pairs, creating an important asset for software clone research.Comment: Accepted to be published in the 41st ACM/IEEE International Conference on Software Engineerin

Teleconnections among tipping elements in the Earth system

Tipping elements are components of the Earth system that may shift abruptly and irreversibly from one state to another at specific thresholds. It is not well understood to what degree tipping of one system can influence other regions or tipping elements. Here, we propose a climate network approach to analyse the global impacts of a prominent tipping element, the Amazon Rainforest Area (ARA). We find that the ARA exhibits strong correlations with regions such as the Tibetan Plateau (TP) and West Antarctic ice sheet. Models show that the identified teleconnection propagation path between the ARA and the TP is robust under climate change. In addition, we detect that TP snow cover extent has been losing stability since 2008. We further uncover that various climate extremes between the ARA and the TP are synchronized under climate change. Our framework highlights that tipping elements can be linked and also the potential predictability of cascading tipping dynamics

Teleconnections among tipping elements in the Earth system

Tipping elements are components of the Earth system that may shift abruptly and irreversibly from one state to another at specific thresholds. It is not well understood to what degree tipping of one system can influence other regions or tipping elements. Here, we propose a climate network approach to analyse the global impacts of a prominent tipping element, the Amazon Rainforest Area (ARA). We find that the ARA exhibits strong correlations with regions such as the Tibetan Plateau (TP) and West Antarctic ice sheet. Models show that the identified teleconnection propagation path between the ARA and the TP is robust under climate change. In addition, we detect that TP snow cover extent has been losing stability since 2008. We further uncover that various climate extremes between the ARA and the TP are synchronized under climate change. Our framework highlights that tipping elements can be linked and also the potential predictability of cascading tipping dynamics.Peer reviewe

An epithelial biomarker signature for idiopathic pulmonary fibrosis: an analysis from the multicentre PROFILE cohort study

Background: Idiopathic Pulmonary Fibrosis (IPF) is a progressive, fatal condition with a variable disease trajectory. The aim of this study was to evaluate potential biomarkers that predict outcome for people with IPF. Method: The PROFILE study is a large prospective longitudinal cohort of treatment naïve IPF patients. We adopted a two-stage discovery and validation design using the PROFILE cohort. For the discovery analysis 106 individuals were examined alongside 50 age and gender matched healthy controls. We undertook an unbiased, multiplex evaluation of 123 biomarkers. Promising, novel, markers were further evaluated by immunohistochemical assessment of IPF lung tissue. The validation analysis examined samples from 206 IPF subjects, from the remaining 212 IPF patients recruited to PROFILE Central England, and were used for replication of the biomarkers identified from the discovery analysis using singleplex assays. This study addressed the predictive power of selected biomarkers to identify individuals with IPF at risk of: 1) progression and 2) death. The PROFILE studies are registered on clinicaltrials.gov (PROFILE Central England NCT01134822; PROFILE Royal Brompton Hospital NCT01110694). Findings: The discovery analysis identified four serum biomarkers (Surfactant Protein D, Matrix Metalloproteinase 7, CA19-9 and CA-125) suitable for replication. Histological assessment of CA19-9 and CA-125 established these proteins as markers of epithelial damage. Replication analysis confirmed that baseline values of SP-D (46.6ng/ml vs 34.6 ng/ml; p =0.002) and CA19-9 (53.7 U/ml vs 22.2 U/ml p<0.001) were significantly higher in patients with progressive disease, and rising levels of CA-125 over 3 months were associated with increased risk of mortality (HR 2.542 CI 1.493-4.328 p<0.001). Interpretation: We have identified serum proteins secreted from metaplastic epithelium that predict disease progression and death in IPF