Privatization and the Market for Corporate Control

We study the wealth effects of the mergers of privatized firms. Our sample entails 39 privatized firms that subsequently become targets of a takeover and 52 privatized firms that become bidders in mergers. Our results indicate that target firms experience a 12 percent increase in equity value at the announcement of a merger. The bidding firms experience a positive but insignificant change in equity value at merger announcement. The results indicate that mergers result in net wealth creation for privatized firms and are consistent with property rights/agency cost theory. The results also offer global, non-U.S. evidence that mergers create wealth.

VISUALIZING SOCIAL ROLES - DESIGN AND EVALUATION OF A BIRD\u27S-EYE VIEW OF SOCIAL NETWORK PRIVACY SETTINGS

The rising usage of Social Network Sites for interacting with contacts from multiple social spheres poses new privacy challenges and increasingly prompts users to manage their online identities. To convey a consistent image of the self when interacting with a group of contacts, at first awareness of previously used social roles is needed. However, existing tools on Social Network Sites to increase such awareness are often spread over different interfaces and the user is left to figure out which contacts have access to which shared items. To address these problems, we introduce the Access Policy Grid, a new visualization offering a bird\u27s-eye view on defined privacy settings that allows identifying social roles and inconsistencies therein. To evaluate our visualization, we present the results of a laboratory experiment involving 32 participants in which we compare the Access Policy Grid to the native Facebook interface. For five out of six research qustions, our results show that the APG outperforms the Facebook interface significantly in terms of at least one of the three investigated aspects (accuracy, confidence, and time-to-task completion)

Assisted Social Identity Management - Enhancing Privacy in the Social Web

The rise of the social web shifts personal identity management to the online world. As a result, personal information is persistently available to all of a user's contacts without distinguishing between dierent contexts such as Work and Leisure. Personal information being available to audiences outside the intended context violates contextual integrity and poses a threat to users' privacy. We argue that a formal description and a conceptualization of the problem scope is required to systematically address current challenges of personal identity management in online social settings. Based thereupon, we propose assisted social identity management to support the user in nding segregated audiences among his contacts as a rst step to advance from the current situation and sketch further improvements. We evaluate our approach using real-world data, demonstrating the feasibility of our proposal

Adaptive identity and access management—contextual data based policies

Due to compliance and IT security requirements, company-wide identity and access management within organizations has gained significant importance in research and practice over the last years. Companies aim at standardizing user management policies in order to reduce administrative overhead and strengthen IT security. These policies provide the foundation for every identity and access management system no matter if poured into IT systems or only located within responsible identity and access management (IAM) engineers’ mind. Despite its relevance, hardly any supportive means for the automated detection and refinement as well as management of policies are available. As a result, policies outdate over time, leading to security vulnerabilities and inefficiencies. Existing research mainly focuses on policy detection and enforcement without providing the required guidance for policy management nor necessary instruments to enable policy adaptibility for today’s dynamic IAM. This paper closes the existing gap by proposing a dynamic policy management process which structures the activities required for policy management in identity and access management environments. In contrast to current approaches, it utilizes the consideration of contextual user management data and key performance indicators for policy detection and refinement and offers result visualization techniques that foster human understanding. In order to underline its applicability, this paper provides an evaluation based on real-life data from a large industrial company

Taxonomy for Social Network Data Types from the Viewpoint of Privacy and User Control

The growing relevance and usage intensity of Online Social Networks (OSNs) along with the accumulation of a large amount of user data has led to privacy concerns among researchers and end users. Despite a large body of research addressing OSN privacy issues, little differentiation of data types on social network sites is made and a generally accepted classification and terminology for such data is missing, hence leading to confusion in related discussions. This paper proposes a taxonomy for data types on OSNs based on a thorough literature analysis and a conceptualization of typical OSN user activities. It aims at clarifying discussions among researchers, benefiting comparisons of data types within and across OSNs and at educating the end user about characteristics and implications of OSN data types. The taxonomy is evaluated by applying it to four major OSNs

Identification and Analysis of a New Hepadnavirus in White Storks

AbstractWe identified, cloned, and functionally characterized a new avian hepadnavirus infecting storks (STHBV). STHBV has the largest DNA genome of all avian hepadnaviruses and, based on sequence and phylogenetic analysis, is most closely related to, but distinct from, heron hepatitis B virus (HHBV). Unique for STHBV among the other avian hepadnaviruses is a potential HNF1 binding site in the preS promoter. In common only with HHBV, STHBV has a myristylation signal on the S and not the preS protein, two C terminally located glycosylation sites on the precore/core proteins and lacks the phosphorylation site essential for the transcriptional transactivation activity of duck-HBV preS protein. The cloned STHBV genomes were competent in gene expression, replication, and viral particle secretion. STHBV infected primary duck hepatocytes very inefficiently suggesting a restricted host range, similar to other hepadnaviruses. This discovery of stork infections unravels novel evolutionary aspects of hepadnaviruses and provides new opportunities for hepadnavirus research

Heme oxygenase-1 overexpression increases liver injury after bile duct ligation in rats

AIM: To investigate the effects of heme oxygenase-1 (HO-1) against oxidant-induced injury caused by bile duct ligation (BDL)