131 research outputs found
An Empirical Study of Bots in Software Development -- Characteristics and Challenges from a Practitioner's Perspective
Software engineering bots - automated tools that handle tedious tasks - are
increasingly used by industrial and open source projects to improve developer
productivity. Current research in this area is held back by a lack of consensus
of what software engineering bots (DevBots) actually are, what characteristics
distinguish them from other tools, and what benefits and challenges are
associated with DevBot usage. In this paper we report on a mixed-method
empirical study of DevBot usage in industrial practice. We report on findings
from interviewing 21 and surveying a total of 111 developers. We identify three
different personas among DevBot users (focusing on autonomy, chat interfaces,
and "smartness"), each with different definitions of what a DevBot is, why
developers use them, and what they struggle with. We conclude that future
DevBot research should situate their work within our framework, to clearly
identify what type of bot the work targets, and what advantages practitioners
can expect. Further, we find that there currently is a lack of general purpose
"smart" bots that go beyond simple automation tools or chat interfaces. This is
problematic, as we have seen that such bots, if available, can have a
transformative effect on the projects that use them.Comment: To be published at the ACM Joint European Software Engineering
Conference and Symposium on the Foundations of Software Engineering
(ESEC/FSE
Challenges in Survey Research
While being an important and often used research method, survey research has
been less often discussed on a methodological level in empirical software
engineering than other types of research. This chapter compiles a set of
important and challenging issues in survey research based on experiences with
several large-scale international surveys. The chapter covers theory building,
sampling, invitation and follow-up, statistical as well as qualitative analysis
of survey data and the usage of psychometrics in software engineering surveys.Comment: Accepted version of chapter in the upcoming book on Contemporary
Empirical Methods in Software Engineering. Update includes revision of typos
and additional figures. Last update includes fixing two small issues and
typo
Comparative analysis and supragenome modeling of twelve Moraxella catarrhalis clinical isolates
Contains fulltext :
97744.pdf (publisher's version ) (Open Access)BACKGROUND: M. catarrhalis is a gram-negative, gamma-proteobacterium and an opportunistic human pathogen associated with otitis media (OM) and exacerbations of chronic obstructive pulmonary disease (COPD). With direct and indirect costs for treating these conditions annually exceeding $33 billion in the United States alone, and nearly ubiquitous resistance to beta-lactam antibiotics among M. catarrhalis clinical isolates, a greater understanding of this pathogen's genome and its variability among isolates is needed. RESULTS: The genomic sequences of ten geographically and phenotypically diverse clinical isolates of M. catarrhalis were determined and analyzed together with two publicly available genomes. These twelve genomes were subjected to detailed comparative and predictive analyses aimed at characterizing the supragenome and understanding the metabolic and pathogenic potential of this species. A total of 2383 gene clusters were identified, of which 1755 are core with the remaining 628 clusters unevenly distributed among the twelve isolates. These findings are consistent with the distributed genome hypothesis (DGH), which posits that the species genome possesses a far greater number of genes than any single isolate. Multiple and pair-wise whole genome alignments highlight limited chromosomal re-arrangement. CONCLUSIONS: M. catarrhalis gene content and chromosomal organization data, although supportive of the DGH, show modest overall genic diversity. These findings are in stark contrast with the reported heterogeneity of the species as a whole, as wells as to other bacterial pathogens mediating OM and COPD, providing important insight into M. catarrhalis pathogenesis that will aid in the development of novel therapeutic regimens
The Pneumococcal Serine-Rich Repeat Protein Is an Intra-Species Bacterial Adhesin That Promotes Bacterial Aggregation In Vivo and in Biofilms
The Pneumococcal serine-rich repeat protein (PsrP) is a pathogenicity island encoded adhesin that has been positively correlated with the ability of Streptococcus pneumoniae to cause invasive disease. Previous studies have shown that PsrP mediates bacterial attachment to Keratin 10 (K10) on the surface of lung cells through amino acids 273–341 located in the Basic Region (BR) domain. In this study we determined that the BR domain of PsrP also mediates an intra-species interaction that promotes the formation of large bacterial aggregates in the nasopharynx and lungs of infected mice as well as in continuous flow-through models of mature biofilms. Using numerous methods, including complementation of mutants with BR domain deficient constructs, fluorescent microscopy with Cy3-labeled recombinant (r)BR, Far Western blotting of bacterial lysates, co-immunoprecipitation with rBR, and growth of biofilms in the presence of antibodies and competitive peptides, we determined that the BR domain, in particular amino acids 122–166 of PsrP, promoted bacterial aggregation and that antibodies against the BR domain were neutralizing. Using similar methodologies, we also determined that SraP and GspB, the Serine-rich repeat proteins (SRRPs) of Staphylococcus aureus and Streptococcus gordonii, respectively, also promoted bacterial aggregation and that their Non-repeat domains bound to their respective SRRPs. This is the first report to show the presence of biofilm-like structures in the lungs of animals infected with S. pneumoniae and show that SRRPs have dual roles as host and bacterial adhesins. These studies suggest that recombinant Non-repeat domains of SRRPs (i.e. BR for S. pneumoniae) may be useful as vaccine antigens to protect against Gram-positive bacteria that cause infection
Conceptual design of a winged hybrid airship
The present study focuses on the sizing and aerodynamic contour design of a two-seater
1000 kg gross take-off mass winged hybrid airship. Unlike the conventional hybrid airships,
which stay aloft and takeoff with the help of VTOL propulsion systems, a winged hybrid
airship requires a certain speed to takeoff by utilizing lift coming from its aerodynamic
surfaces. Heaviness fraction and takeoff ground roll are considered as measure of merit in
initial sizing. Based on the design requirement of Malaysian inter-island tourism and
transportation of agricultural products, range is set to 450 km and ground roll for take-off
about 150 m. For the airship to be heavy enough for ground handling, the ratio of
hydrostatic to hydrodynamic lift is set equal to 49:51. Summary of the results to be obtained
in early design phase will give a baseline start to study the aerodynamics and stability
characteristics of such airships in future
Termite sensitivity to temperature affects global wood decay rates.
Deadwood is a large global carbon store with its store size partially determined by biotic decay. Microbial wood decay rates are known to respond to changing temperature and precipitation. Termites are also important decomposers in the tropics but are less well studied. An understanding of their climate sensitivities is needed to estimate climate change effects on wood carbon pools. Using data from 133 sites spanning six continents, we found that termite wood discovery and consumption were highly sensitive to temperature (with decay increasing >6.8 times per 10°C increase in temperature)-even more so than microbes. Termite decay effects were greatest in tropical seasonal forests, tropical savannas, and subtropical deserts. With tropicalization (i.e., warming shifts to tropical climates), termite wood decay will likely increase as termites access more of Earth's surface
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