A spinose appendage fragment of a problematic arthropod from the Early Ordovician of Morocco

A highly spinose fragment of a possibly raptorial appendage from the Arenig (Early Ordovician) of the Upper Fezouata Formation north of Zagora, southeastern Morocco is described as the arthropod Pseudoangustidontus duplospineus gen. et sp. nov. The single fragmentary specimen displays a unique morphology, carrying at least 39 pairs of spines (i.e., 78 spines) of very regularly alternating lengths. Pseudoangustidontus gen. nov. shows some similarities to a number of spinose arthropod appendages and appendage parts, most notably to the spine-bearing podomeres of the third prosomal appendage of megalograptid eurypterids and the problematic and incompletely known genus Angustidon tits. However, megalograptids and Angustidontus both have a lower spine count, while the latter also carries only a single row of spines. Because no known arthropod displays a morphology closely comparable to that of Pseudoangustidontus gen. nov., the affinities of the new fossil within Arthropoda remain uncertain

Controlling service work: An ambiguous accomplishment between employees, management and customers

In order to understand the control of service work, most service literature has focused on its production while treating the customer as secondary. The consumption literature emphasizes the customer’s role but lacks empirical evidence for its claims. Using an ethnographic study of an ‘exclusive’ department store, this article aims to reduce the gap between these two bodies of literature by investigating how employees, management and customers control service work. The findings suggest that the maintenance of class difference combined with competing expectations of managers, employees and customers makes the management of service work highly ambiguous and reveals a continuing instability between managerial practices of control and consumer culture

Entrepreneurial exit in real and imagined markets

Entrepreneurs exit their business due to selection pressures experienced in the market place, i.e. business failure. Next to this well known ex-post decision to exit, entrepreneurs select exantewhether they are willing to pursue an entrepreneurial career at all, or to give up theseentrepreneurial intentions. Hardly anything is known about the latter selection process in imagined markets that precedes the variety creation and selection process in real markets. This paper explores and explains the prevalence of these two selection processes using survey data on 20,000 individuals in 27 European countries and the US in 2007. We distinguish business failures from exit by sell-off. Results indicate that individuals in the US are less likely to exit imagined markets, and are more likely to have exited the real market (especially by selling their business) than Europeans. Individuals in a Corporatist welfare state regime have relatively high chances to exit imagined markets. Business owners in urban environments are more likely to fail, while individuals with a high risk tolerance, a high education and self-employed parents are less likely to exit in imagined as well as in real markets (via business failure). This study shows that exit in real and in imagined markets is differently affected by competition and institutions. These selection environments have differential effects on entrepreneurial aspirations and actions of individuals, and provide evidence for the dissimilar nature of exit in real and exit in imagined markets.

On-Demand Big Data Integration: A Hybrid ETL Approach for Reproducible Scientific Research

Scientific research requires access, analysis, and sharing of data that is distributed across various heterogeneous data sources at the scale of the Internet. An eager ETL process constructs an integrated data repository as its first step, integrating and loading data in its entirety from the data sources. The bootstrapping of this process is not efficient for scientific research that requires access to data from very large and typically numerous distributed data sources. a lazy ETL process loads only the metadata, but still eagerly. Lazy ETL is faster in bootstrapping. However, queries on the integrated data repository of eager ETL perform faster, due to the availability of the entire data beforehand. In this paper, we propose a novel ETL approach for scientific data integration, as a hybrid of eager and lazy ETL approaches, and applied both to data as well as metadata. This way, Hybrid ETL supports incremental integration and loading of metadata and data from the data sources. We incorporate a human-in-the-loop approach, to enhance the hybrid ETL, with selective data integration driven by the user queries and sharing of integrated data between users. We implement our hybrid ETL approach in a prototype platform, Obidos, and evaluate it in the context of data sharing for medical research. Obidos outperforms both the eager ETL and lazy ETL approaches, for scientific research data integration and sharing, through its selective loading of data and metadata, while storing the integrated data in a scalable integrated data repository.Comment: Pre-print Submitted to the DMAH Special Issue of the Springer DAPD Journa

Factors Influencing the Entrepreneurial Engagement of Opportunity and Necessity Entrepreneurs

This paper investigates determinants of engagement in various stages of the entrepreneurial process while considering an individual's start-up motivation using 2007 survey data for 27 European countries and the US. Next to opportunity and necessity start-up motivations, we take into account individuals driven by a combination of both motivations. We observe that opportunity- and necessitydriven entrepreneurs as well as those with mixed start-up motivations have different profiles. Furthermore, they differ concerning the factors that inspire or hinder them to engage in the entrepreneurial process more fully ('to climb the entrepreneurial ladder'). For example, entrepreneurship-specific education, selfemployed parents, risk tolerance, perception of lack of financial support, and living in a metropolitan area are important variables in determining entrepreneurial engagement and failure for opportunity-driven individuals, but they are not (or less) important for necessity-driven individuals.

Modelling latent and actual entrepreneurship

The determinants of latent (i.e., desired) and actual entrepreneurship are analysed in two ways with nearly 8,000 observations from the 2004 “Flash Eurobarometer survey on Entrepreneurship” covering the 25 European Union member states and the United States. Both methods lead to new and extensive insights in the interrelation of both concepts. First, latent and actual entrepreneurship are investigated simultaneously in a bivariate probit setting. The perception of lack of financial support, the perception of administrative complexities, and the perception of lack of sufficient information do not have significant direct impacts on latent entrepreneurship. This points at indirect effects of these variables on latent entrepreneurship via actual entrepreneurship. Second, four groups of individuals are distinguished, based on their involvement in both measures of entrepreneurship. The analysis enables us for example to discuss the determinants of ‘necessity entrepreneurship’. Results show that the perception of administrative complexities is a significant obstacle in setting up a business, irrespective of the declared preference for self-employment, while the perception of financial constraints does not have a significant influence. Also, necessity entrepreneurs are characterized by a relatively low education level compared to those who are neither latent nor actual entrepreneurs. Each model has its own merits. The multinomial model enables researchers to perform group-wise analyses, while the bivariate probit model makes is possible to take into account the importance of latent entrepreneurship without explicitly including latent entrepreneurship in the set of explanatory variables.

Entrepreneurial exit and entrepreneurial engagement

Arguing that entrepreneurial exit is an indicator of accumulated entrepreneurial human capital (like ability and experience) we investigate whether such an exit in the recent past positively relates to posterior engagement in various stages of the entrepreneurial process (i.e. potential, intentional, nascent, young, and established entrepreneurship). We use individual-level data for 24 countries that participated in the Global Entrepreneurship Monitor during the years 2004, 2005 and 2006 (some 350,000 observations). Our findings indeed show that recent exit experience decreases the probability of undertaking no entrepreneurial activity, and that it increases the probabilities of being a potential or an intentional entrepreneur. We also investigate under what conditions recent exit increases engagement in entrepreneurial activities. Most important factors that influence entrepreneurial (re-)engagement are gender, fear of failure and knowing an entrepreneur, while educational attainment does not seem to be relevant. Also, some interesting country differences are found. �

Achlys : Towards a framework for distributed storage and generic computing applications for wireless IoT edge networks with Lasp on GRiSP

Internet of Things (IoT) has gained substantial attention over the past years. And the main discussion has been how to process the amount of data that it generates which has lead to the edge computing paradigm. Wether it is called fog1, edge or mist, the principle remains that cloud services must become available closer to clients. This documents presents ongoing work on future edge systems that are built to provide steadfast IoT services to users by bringing storage and processing power closer to peripheral parts of networks. Designing such infrastructures is becoming much more challenging as the number of IoT devices keeps growing. Production grade deployments have to meet very high performance requirements, and end-to-end solutions involve significant investments. In this paper, we aim at providing a solution to extend the range of the edge model to the very farthest nodes in the network. Specifically, we focus on providing reliable storage and computation capabilities immediately on wireless IoT sensor nodes. This extended edge model will allow end users to manage their IoT ecosystem without forcibly relying on gateways or Internet provider solutions. In this document, we introduce Achlys, a prototype implementation of an edge node that is a concrete port of the Lasp programming library on the GRiSP Erlang embedded system. This way, we aim at addressing the need for a general purpose edge that is both resilient and consistent in terms of storage and network. Finally, we study example use cases that could take advantage of integrating the Achlys framework and discuss future work for the latter.Comment: 7 page