Poster: Communication in Open-Source Projects--End of the E-mail Era?

Communication is essential in software engineering. Especially in distributed open-source teams, communication needs to be supported by channels including mailing lists, forums, issue trackers, and chat systems. Yet, we do not have a clear understanding of which communication channels stakeholders in open-source projects use. In this study, we fill the knowledge gap by investigating a statistically representative sample of 400 GitHub projects. We discover the used communication channels by regular expressions on project data. We show that (1) half of the GitHub projects use observable communication channels; (2) GitHub Issues, e-mail addresses, and the modern chat system Gitter are the most common channels; (3) mailing lists are only in place five and have a lower market share than all modern chat systems combined.Comment: 2 pages. To appear as a poster in 40th International Conference on Software Engineering (ICSE 2018) Companion proceeding

How Are Communication Channels on GitHub Presented to Their Intended Audience? -- A Thematic Analysis

Communication is essential in software development, and even more in distributed settings. Communication activities need to be organized and coordinated to defend against the threat of productivity losses, increases in cognitive load, and stress among team members. With a plethora of communication channels that were identified by previous research in open-source projects, there is a need to explore organizational issues in how these communication channels are introduced, explained, and motivated for use among all project members. In this study, we wanted to understand which communication channels are used in GitHub projects and how they are presented to the GitHub project audience. We employed thematic analysis to analyze 151 artifacts in 90 GitHub projects. Our results revealed 32 unique communications channels that can be divided into nine different types. Projects mostly provide channels of different types, but for some types (e.g., chat) it is common to provide several channels. Maintainers are aware that channels have different properties and help the developers to decide which channel should be used in which case. However, this is not true for all projects, and often we have not found any explicit reasons why maintainers chose to provide one channel over another. Different channels can be used for different purposes and have different affordances, so maintainers have to decide wisely which channels they want to provide and make clear which channel should be used in which case. Otherwise, developers might feel overwhelmed of too many channels and information can get fragmented over multiple channels.Comment: 10 pages, 5 figures. Accepted for presentation at the International Conference on Evaluation and Assessment in Software Engineering (EASE) 202

Arbuscular mycorrhizas in phosphate-polluted soil: interrelations between root colonization and nitrogen

To investigate whether arbuscular mycorrhizal fungi (AMF) – abundant in a phosphate-polluted but nitrogen-poor field site – improve plant N nutrition, we carried out a two-factorial experiment, including N fertilization and fungicide treatment. Percentage of root length colonized (% RLC) by AMF and tissue element concentrations were determined for four resident plant species. Furthermore, soil nutrient levels and N effects on aboveground biomass of individual species were measured. Nitrogen fertilization lowered % RLC by AMF of Artemisia vulgaris L., Picris hieracioides L. and Poa compressa L., but not of Bromus japonicus Thunb. This – together with positive N addition effects on N status, N:P-ratio and aboveground biomass of most species – suggested that plants are mycorrhizal because of N deficiency. Fungicide treatment, which reduced % RLC in all species, resulted in lower N concentrations in A. vulgaris and P. hieracioides, a higher N concentration in P. compressa, and did not consistently affect N status of B. japonicus. Evidently, AMF had an influence on the N nutrition of plants in this P-rich soil; however – potentially due to differences in their mycorrhizal responsiveness – not all species seemed to benefit froma mycorrhiza-mediated N uptake and accordingly, N distribution

Epistemic dilemma and epistemic conflict

In this paper, I will examine the notion of an epistemic dilemma, its characterizations in the literature, and the different intuitions prompted by it. I will illustrate that the notion of an epistemic dilemma is expected to capture various phenomena that are not easily unified with one concept: while some aspects of these phenomena are more about the agent in a certain situation, other aspects seem to be more about the situation as such. As a consequence, incompatible intuitions emerge concerning the transparency of epistemic dilemmas as well as regarding the role that doxastic suspension plays in resolving cases of epistemic dilemma. I suggest to distinguish between the mental state of agents who find themselves in an epistemic dilemma and the normative situation that gives rise to a dilemma. I will refer to the agent’s mental state as epistemic conflict and will reserve the term epistemic dilemma for evidential situations in which epistemic principles either recommend incompatible doxastic responses or render all options impermissible. The concept of epistemic conflict not only captures the mental state of agents who find themselves in a genuine epistemic dilemma but also applies to agents who face difficult epistemic choices that they cannot resolve without substantial cognitive (and often pragmatic) effort, for example, via doxastic suspension

Perception of Risks and Usefulness of Smart Video Surveillance Systems

The number of video cameras in public places increases due to different reasons such as detecting dangers (e.g., thefts, robberies, terrorist attacks) and security breaches in crowds. The application of video surveillance systems is sometimes evaluated ambivalently; therefore, the presented study focuses on factors influencing the acceptance of a privacy-friendly, smart video surveillance system. Overall, 216 persons aged between 18 and 81 years participated in an online survey. In terms of the perceived usefulness, there are significant interactions of public spaces × gender and public spaces × time of day. In addition, the assessment of different privacy levels of a video surveillance system differ significantly in terms of perceived risk. Interestingly, men rate the risk concerning their own privacy significantly higher than women do. Participants rate the presented system as fairly useful and slightly risky for their own privacy. The findings of the presented exploratory study provide insight into how people perceive smart video surveillance. These findings have the potential to support the conditions of the use of smart video surveillance systems and to address the possibly affected individuals

Zetetic Seemings and Their Role in Inquiry

The paper addresses the nature of seemings in light of their role in inquiry. Seemings are mental states or events with propositional content that have a specific phenomenology often referred to as “felt truth”. In epistemology, seemings are mainly discussed as possible (non-inferential) justifications for belief. Yet, epistemology has recently taken a zetetic turn, that is, a turn toward the study of inquiry. I will argue that the role of seemings in epistemology should be re-assessed from the perspective of inquiry and deliberation. Seemings may fall short of justifying beliefs, but there is an important role for seemings in the zetetic realm, which may also explain why seemings lack direct justificatory force for beliefs. Seemings, so I will suggest, can provide normative reasons for performing certain zetetic tasks, but they cannot provide normative reasons for making up one’s mind about the inquired question. In this sense, the zetetic role of seemings can be described as guiding rational inquiry. I will suggest that a modified version of the so-called Taking Evidence View about the nature of seemings is best fitted to accommodate their zetetic role. Yet, contra existing versions of the Taking Evidence View, my modified account acknowledges that seemings are genuine experiences (of one’s evidential standing during inquiry) that are accompanied by the characteristic phenomenology of what is called a “feeling of truth”. By doing so, my modified version of the Taking Evidence View incorporates the (as I take it) most important feature of the rival Experience View of seemings

Chemokines: A New Dendritic Cell Signal for T Cell Activation

Dendritic cells (DCs) are the main inducers and regulators of cytotoxic T lymphocyte (CTL) responses against viruses and tumors. One checkpoint to avoid misguided CTL activation, which might damage healthy cells of the body, is the necessity for multiple activation signals, involving both antigenic as well as additional signals that reflect the presence of pathogens. DCs provide both signals when activated by ligands of pattern recognition receptors and “licensed” by helper lymphocytes. Recently, it has been established that such T cell licensing can be facilitated by CD4+ T helper cells (“classical licensing”) or by natural killer T cells (“alternative licensing”). Licensing regulates the DC/CTL cross-talk at multiple layers. Direct recruitment of CTLs through chemokines released by licensed DCs has recently emerged as a common theme and has a crucial impact on the efficiency of CTL responses. Here, we discuss recent advances in our understanding of DC licensing for cross-priming and implications for the temporal and spatial regulation underlying this process. Future vaccination strategies will benefit from a deeper insight into the mechanisms that govern CTL activation