2,589 research outputs found

    A value proposition oriented typology of electronic marketplaces for B2B SaaS applications

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    In order to overcome the lack of transparency of the SaaS market, electronic marketplaces (EMs) emerge in practice. To the best of our knowledge, only little research has been carried out in this specific domain. As it is of outmost importance to understand the value offerings, the goal of this paper is to develop a typology of EMs considering the value proposition and other differentiating characteristics. An explorative multiple case study approach is employed analyzing 17 cases utilizing publically available data. We propose a five-step-typology, in particular: (1) Catalogue Listing, (2) Transaction-oriented Catalogue, (3) All-in-One Marketplace, (4) Development Platform Marketing Channel and (5) Industry Collaboration Development Platform. In addition, we analyze and discuss the general market situation of EMs for B2B SaaS applications. Based on our findings, we derive implications for practice and identify potential for further research

    Underwater Reactor Inspector Nuclear Fuel Inspecting Drone

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    The Underwater Reactor Inspector (URI) is a tethered and radiation resistant remotely operated underwater vehicle (ROV) designated to operate within the reactor pool of the Rhode Island Nuclear Science Center (RINSC). The main purpose of the ROV is to be able to inspect the core elements of the reactor within the pool. The design process was done by brainstorming multiple different designs and optimizing them based off the ease of the design as well as the engineering process that each design featured. The final design consists of all significant aspects for the ROV to achieve its’ goal. The URI underwent a redesign at the beginning of the year which has made the current product smaller and cheaper to make. It utilizes a periscope which in this case is an angled mirror to show a perpendicular view from the orientation of the camera. Shielded by three feet of water and more than three quarters an inch of Lead, the camera and other contents in the electronics bottle will be protected from gamma radiation ensuring that the effective dosage will not exceed the operable dosage rate of 50 Gy/hr. The ROV will receive power from the topside of the pool via tether which also is how the ROV is controlled

    Noncoding Sequences Near Duplicated Genes Evolve Rapidly

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    Gene expression divergence and chromosomal rearrangements have been put forward as major contributors to phenotypic differences between closely related species. It has also been established that duplicated genes show enhanced rates of positive selection in their amino acid sequences. If functional divergence is largely due to changes in gene expression, it follows that regulatory sequences in duplicated loci should also evolve rapidly. To investigate this hypothesis, we performed likelihood ratio tests (LRTs) on all noncoding loci within 5 kb of every transcript in the human genome and identified sequences with increased substitution rates in the human lineage since divergence from Old World Monkeys. The fraction of rapidly evolving loci is significantly higher nearby genes that duplicated in the common ancestor of humans and chimps compared with nonduplicated genes. We also conducted a genome-wide scan for nucleotide substitutions predicted to affect transcription factor binding. Rates of binding site divergence are elevated in noncoding sequences of duplicated loci with accelerated substitution rates. Many of the genes associated with these fast-evolving genomic elements belong to functional categories identified in previous studies of positive selection on amino acid sequences. In addition, we find enrichment for accelerated evolution nearby genes involved in establishment and maintenance of pregnancy, processes that differ significantly between humans and monkeys. Our findings support the hypothesis that adaptive evolution of the regulation of duplicated genes has played a significant role in human evolution

    Looking Beyond Data Through the Ages

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    Abstract: Accessing data has always been crucial in order to get access to (cultural) knowledge. But in the new ages different challenges arise to keep complex data accessible. Concerning these challenges a linguistic use case, which has been set up in 1993, serves as an example to show that it might be hard to re-enact an old system in order to reuse its research data and processes. Re-enacting the old system showed that other crucial points emerge in the context of research data management that need attention. In order to increase the probability of gaining access to research data in the future Data Management Plans can be identified as central tool. Although preservation of and creating access to data is a global task, the scientific management of data is still strongly shaped through national regulations and practices and hence delivers a quite fragmented picture

    Decentralized Documentation of Maritime Traffic Incidents to Support Conflict Resolution

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    For the investigation of major traffic accidents, larger vessels are obliged to install a voyage data recorder (VDR). However, not every vessel is equipped with a VDR, and the readout is often a manual process that is costly. In addition, not only ship-related information can be relevant for reconstructing traffic accidents, but also information from other entities such as meteorological services or port operators. Moreover, another major challenge is that entities tend to trust only their records, and not those of others as these could be manipulated in favor of the particular recording entity (e.g., to disguise any damage caused). This paper presents an approach to documenting arbitrary data from different entities in a trustworthy, decentralized, and tamper-proof manner to support the conflict resolution process. For this purpose, all involved entities in a traffic situation can contribute to the documentation by persisting their available data. Since maritime stakeholders are equipped with various sensors, a diverse and meaningful data foundation can be aggregated. The data is then signed by a mutually agreed upon timestamping authority (TSA). In this way, everyone can cryptographically verify whether the data has been subsequently changed. This approach was successfully applied in practice by documenting a vessel’s mooring maneuver

    CENP-C facilitates the recruitment of M18BP1 to centromeric chromatin

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    Centromeres are important structural constituents of chromosomes that ensure proper chromosome segregation during mitosis by providing defined sites for kinetochore attachment. In higher eukaryotes, centromeres have no specific DNA sequence and thus, they are rather determined through epigenetic mechanisms. A fundamental process in centromere establishment is the incorporation of the histone variant CENP-A into centromeric chromatin, which provides a binding platform for the other centromeric proteins. The Mis18 complex, and, in particular, its member M18BP1 was shown to be essential for both incorporation and maintenance of CENP-A

    Assessing zoo giraffe survivorship: Methodological aspects, historical improvement and a rapid demographic shift

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    Giraffe have been kept in zoos for a long time. They have traditionally been considered difficult to maintain due to various husbandry requirements, including their nature as intrinsic browsers. However, zoo animals are expected to achieve higher survivorship than free-ranging conspecifics due to protection against dangers that would be experienced in their natural habitat. Global zoo giraffe data was analysed for historical developments of juvenile and adult survivorship, assessing the data with various demographic measures and comparing it to that of populations from natural habitats. Additionally, zoo population structure was analysed, in particular with respect to two events that occurred in parallel in 2014—a recommendation to restrict the number of new offspring given by the European Endangered Species Programme (EEP) studbook coordinator and the culling of a designated ‘surplus’ giraffe at Copenhagen Zoo that attracted global media attention. Both juvenile and adult giraffe survivorship has increased over time, suggesting advances in giraffe husbandry. For juveniles, this process has been continuous, whereas for adults the major progress has been in the most recent cohort (from 2000 onwards), in parallel with the publication of various husbandry guidelines. Zoo giraffe survivorship is now generally above that observed in natural habitats. Simple survivorship analyses appear suitable to describe these developments. Since 2014, the global giraffe population has undergone a rapid demographic shift from a growing to an ageing population, indicating a drastic limitation of reproduction rather than a system where reproduction is allowed and selected animals are killed (and possibly fed to carnivores). Thus, giraffe are both a showcase example for the historical progress made in zoo animal husbandry due to efforts of the zoo community and serve as an example to discuss implications of different methods of zoo population management

    ISA-TAB-Nano: A Specification for Sharing Nanomaterial Research Data in Spreadsheet-based Format

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    BACKGROUND AND MOTIVATION: The high-throughput genomics communities have been successfully using standardized spreadsheet-based formats to capture and share data within labs and among public repositories. The nanomedicine community has yet to adopt similar standards to share the diverse and multi-dimensional types of data (including metadata) pertaining to the description and characterization of nanomaterials. Owing to the lack of standardization in representing and sharing nanomaterial data, most of the data currently shared via publications and data resources are incomplete, poorly-integrated, and not suitable for meaningful interpretation and re-use of the data. Specifically, in its current state, data cannot be effectively utilized for the development of predictive models that will inform the rational design of nanomaterials. RESULTS: We have developed a specification called ISA-TAB-Nano, which comprises four spreadsheet-based file formats for representing and integrating various types of nanomaterial data. Three file formats (Investigation, Study, and Assay files) have been adapted from the established ISA-TAB specification; while the Material file format was developed de novo to more readily describe the complexity of nanomaterials and associated small molecules. In this paper, we have discussed the main features of each file format and how to use them for sharing nanomaterial descriptions and assay metadata. CONCLUSION: The ISA-TAB-Nano file formats provide a general and flexible framework to record and integrate nanomaterial descriptions, assay data (metadata and endpoint measurements) and protocol information. Like ISA-TAB, ISA-TAB-Nano supports the use of ontology terms to promote standardized descriptions and to facilitate search and integration of the data. The ISA-TAB-Nano specification has been submitted as an ASTM work item to obtain community feedback and to provide a nanotechnology data-sharing standard for public development and adoption

    Visual Analysis of Hyperproperties for Understanding Model Checking Results

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    Model checkers provide algorithms for proving that a mathematical model of a system satisfies a given specification. In case of a violation, a counterexample that shows the erroneous behavior is returned. Understanding these counterexamples is challenging, especially for hyperproperty specifications, i.e., specifications that relate multiple executions of a system to each other. We aim to facilitate the visual analysis of such counterexamples through our HYPERVIS tool, which provides interactive visualizations of the given model, specification, and counterexample. Within an iterative and interdisciplinary design process, we developed visualization solutions that can effectively communicate the core aspects of the model checking result. Specifically, we introduce graphical representations of binary values for improving pattern recognition, color encoding for better indicating related aspects, visually enhanced textual descriptions, as well as extensive cross-view highlighting mechanisms. Further, through an underlying causal analysis of the counterexample, we are also able to identify values that contributed to the violation and use this knowledge for both improved encoding and highlighting. Finally, the analyst can modify both the specification of the hyperproperty and the system directly within HYPERVIS and initiate the model checking of the new version. In combination, these features notably support the analyst in understanding the error leading to the counterexample as well as iterating the provided system and specification. We ran multiple case studies with HYPERVIS and tested it with domain experts in qualitative feedback sessions. The participants’ positive feedback confirms the considerable improvement over the manual, text-based status quo and the value of the tool for explaining hyperproperties

    Re-Assembly of the Genome of Francisella tularensis Subsp. holarctica OSU18

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    Francisella tularensis is a highly infectious human intracellular pathogen that is the causative agent of tularemia. It occurs in several major subtypes, including the live vaccine strain holarctica (type B). F. tularensis is classified as category A biodefense agent in part because a relatively small number of organisms can cause severe illness. Three complete genomes of subspecies holarctica have been sequenced and deposited in public archives, of which OSU18 was the first and the only strain for which a scientific publication has appeared [1]. We re-assembled the OSU18 strain using both de novo and comparative assembly techniques, and found that the published sequence has two large inversion mis-assemblies. We generated a corrected assembly of the entire genome along with detailed information on the placement of individual reads within the assembly. This assembly will provide a more accurate basis for future comparative studies of this pathogen
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