WHEN IS CROWDSOURCING ADVANTAGEOUS? THE CASE OF CROWDSOURCED SOFTWARE TESTING

Crowdsourcing describes a novel mode of value creation in which organizations broadcast tasks that have been previously performed in-house to a large magnitude of Internet users that perform these tasks. Although the concept has gained maturity and has proven to be an alternative way of problem-solving, an organizational cost-benefit perspective has largely been neglected by existing research. More specifically, it remains unclear when crowdsourcing is advantageous in comparison to alterna-tive governance structures such as in-house production. Drawing on crowdsourcing literature and transaction action cost theory, we present two case studies from the domain of crowdsourced software testing. We systematically analyze two organizations that applied crowdtesting to test a mobile appli-cation. As both organizations tested the application via crowdtesting and their traditional in-house testing, we are able to relate the effectiveness of crowdtesting and the associated costs to the effective-ness and costs of in-house testing. We find that crowdtesting is comparable in terms of testing quality and costs, but provides large advantages in terms of speed, heterogeneity of testers and user feedback as added value. We contribute to the crowdsourcing literature by providing first empirical evidence about the instances in which crowdsourcing is an advantageous way of problem solving

Seamless Gene Tagging by Endonuclease-Driven Homologous Recombination

Gene tagging facilitates systematic genomic and proteomic analyses but chromosomal tagging typically disrupts gene regulatory sequences. Here we describe a seamless gene tagging approach that preserves endogenous gene regulation and is potentially applicable in any species with efficient DNA double-strand break repair by homologous recombination. We implement seamless tagging in Saccharomyces cerevisiae and demonstrate its application for protein tagging while preserving simultaneously upstream and downstream gene regulatory elements. Seamless tagging is compatible with high-throughput strain construction using synthetic genetic arrays (SGA), enables functional analysis of transcription antisense to open reading frames and should facilitate systematic and minimally-invasive analysis of gene functions

Thiolutin is a zinc chelator that inhibits the Rpn11 and other JAMM metalloproteases

Thiolutin is a disulfide-containing antibiotic and anti-angiogenic compound produced by Streptomyces. Its biological targets are not known. We show that reduced thiolutin is a zinc chelator that inhibits the JAB1/MPN/Mov34 (JAMM) domain–containing metalloprotease Rpn11, a deubiquitinating enzyme of the 19S proteasome. Thiolutin also inhibits the JAMM metalloproteases Csn5, the deneddylase of the COP9 signalosome; AMSH, which regulates ubiquitin-dependent sorting of cell-surface receptors; and BRCC36, a K63-specific deubiquitinase of the BRCC36-containing isopeptidase complex and the BRCA1–BRCA2-containing complex. We provide evidence that other dithiolopyrrolones also function as inhibitors of JAMM metalloproteases

The Baker's Yeast Diploid Genome Is Remarkably Stable in Vegetative Growth and Meiosis

Accurate estimates of mutation rates provide critical information to analyze genome evolution and organism fitness. We used whole-genome DNA sequencing, pulse-field gel electrophoresis, and comparative genome hybridization to determine mutation rates in diploid vegetative and meiotic mutation accumulation lines of Saccharomyces cerevisiae. The vegetative lines underwent only mitotic divisions while the meiotic lines underwent a meiotic cycle every ∼20 vegetative divisions. Similar base substitution rates were estimated for both lines. Given our experimental design, these measures indicated that the meiotic mutation rate is within the range of being equal to zero to being 55-fold higher than the vegetative rate. Mutations detected in vegetative lines were all heterozygous while those in meiotic lines were homozygous. A quantitative analysis of intra-tetrad mating events in the meiotic lines showed that inter-spore mating is primarily responsible for rapidly fixing mutations to homozygosity as well as for removing mutations. We did not observe 1–2 nt insertion/deletion (in-del) mutations in any of the sequenced lines and only one structural variant in a non-telomeric location was found. However, a large number of structural variations in subtelomeric sequences were seen in both vegetative and meiotic lines that did not affect viability. Our results indicate that the diploid yeast nuclear genome is remarkably stable during the vegetative and meiotic cell cycles and support the hypothesis that peripheral regions of chromosomes are more dynamic than gene-rich central sections where structural rearrangements could be deleterious. This work also provides an improved estimate for the mutational load carried by diploid organisms

PEG−peptide conjugates

The remarkable diversity of the self-assembly behavior of PEG−peptides is reviewed, including self-assemblies formed by PEG−peptides with β-sheet and α-helical (coiled-coil) peptide sequences. The modes of self-assembly in solution and in the solid state are discussed. Additionally, applications in bionanotechnology and synthetic materials science are summarized

The PREDICTS database: a global database of how local terrestrial biodiversity responds to human impacts

Biodiversity continues to decline in the face of increasing anthropogenic pressures such as habitat destruction, exploitation, pollution and introduction of alien species. Existing global databases of species’ threat status or population time series are dominated by charismatic species. The collation of datasets with broad taxonomic and biogeographic extents, and that support computation of a range of biodiversity indicators, is necessary to enable better understanding of historical declines and to project – and avert – future declines. We describe and assess a new database of more than 1.6 million samples from 78 countries representing over 28,000 species, collated from existing spatial comparisons of local-scale biodiversity exposed to different intensities and types of anthropogenic pressures, from terrestrial sites around the world. The database contains measurements taken in 208 (of 814) ecoregions, 13 (of 14) biomes, 25 (of 35) biodiversity hotspots and 16 (of 17) megadiverse countries. The database contains more than 1% of the total number of all species described, and more than 1% of the described species within many taxonomic groups – including flowering plants, gymnosperms, birds, mammals, reptiles, amphibians, beetles, lepidopterans and hymenopterans. The dataset, which is still being added to, is therefore already considerably larger and more representative than those used by previous quantitative models of biodiversity trends and responses. The database is being assembled as part of the PREDICTS project (Projecting Responses of Ecological Diversity In Changing Terrestrial Systems – www.predicts.org.uk).We make site-level summary data available alongside this article. The full database will be publicly available in 2015

ADAPTATION BARRIERS IN INTERNAL CROWDSOURCING: A MULTIPLE CASE STUDY

Recently, the application of internal crowdsourcing in companies as a new form of orchestrating work has increased substantially. Early research has shown that organizations should apply internal crowdsourcing due to its benefits, such as fast access to internal knowledge and increased productivi-ty. Although studies have identified some advantages, internal crowdsourcing is a complex initiative and we do not sufficiently know how to rollout internal crowdsourcing initiatives in a company and to guide them to a state of stable operations in the adaptation stage. Some papers derived barriers for internal crowdsourcing and solutions on how to overcome them. However, these barriers address mostly the operational stage, when the initiative is already stable. Some papers address adaptation barriers, but the assessment frameworks in current literature used to detect them were incomprehen-sive resulting in only few adaptation barriers and solutions. Therefore, we identify the adaptation bar-riers of internal crowdsourcing comprehensively through the technochange theory in a multiple case study, assess what solutions the companies applied and describe how the solutions work in order to display how to overcome barriers in a consolidated introduction model for internal crowdsourcing

Leveraging the Internal Work Force through Crowdtesting “ Crowdsourcing in Banking

The teaching case highlights the design and change management challenges of an IT department in the financial service industry designing and introducing an internal crowdtesting system to overcome challenges of the digital transformation. The digitalizat

HOW TO DESIGN AN INTERNAL CROWDSOURCING SYSTEM

Digitalization gives rise to dynamic forces shaping future working structures. In practice, companies are increasingly interested in using their own employees as an internal crowd. Drawing on socio-technical systems (STS) perspective, organizations must understand how they can embed an internal crowdsourcing system effectively in order to exploit its potential. In particular, organizations need assistance in designing internal crowdsourcing systems. Thus, we follow an action design research approach and develop comprehensive design guidelines for designing an internal crowdsourcing system. The paper in hand develops the design guidelines by deriving the requirements from literature, developing them further in a bank project and evaluating them with external experts. Furthermore, we assess what tools can cover which part of the system and implement the system. The short paper will present the derived requirements, the first design of the internal crowdsourcing system and explain next steps of the full paper as well as the contribution

Sex without crossing over in the yeast Saccharomycodes ludwigii

Background Intermixing of genomes through meiotic reassortment and recombination of homologous chromosomes is a unifying theme of sexual reproduction in eukaryotic organisms and is considered crucial for their adaptive evolution. Previous studies of the budding yeast species Saccharomycodes ludwigii suggested that meiotic crossing over might be absent from its sexual life cycle, which is predominated by fertilization within the meiotic tetrad. Results We demonstrate that recombination is extremely suppressed during meiosis in Sd. ludwigii. DNA double-strand break formation by the conserved transesterase Spo11, processing and repair involving interhomolog interactions are required for normal meiosis but do not lead to crossing over. Although the species has retained an intact meiotic gene repertoire, genetic and population analyses suggest the exceptionally rare occurrence of meiotic crossovers in its genome. A strong AT bias of spontaneous mutations and the absence of recombination are likely responsible for its unusually low genomic GC level. Conclusions Sd. ludwigii has followed a unique evolutionary trajectory that possibly derives fitness benefits from the combination of frequent mating between products of the same meiotic event with the extreme suppression of meiotic recombination. This life style ensures preservation of heterozygosity throughout its genome and may enable the species to adapt to its environment and survive with only minimal levels of rare meiotic recombination. We propose Sd. ludwigii as an excellent natural forum for the study of genome evolution and recombination rates