Delivering Live Multimedia Streams to Mobile Hosts in a Wireless Internet with Multiple Content Aggregators

We consider the distribution of channels of live multimedia content (e.g., radio or TV broadcasts) via multiple content aggregators. In our work, an aggregator receives channels from content sources and redistributes them to a potentially large number of mobile hosts. Each aggregator can offer a channel in various configurations to cater for different wireless links, mobile hosts, and user preferences. As a result, a mobile host can generally choose from different configurations of the same channel offered by multiple alternative aggregators, which may be available through different interfaces (e.g., in a hotspot). A mobile host may need to handoff to another aggregator once it receives a channel. To prevent service disruption, a mobile host may for instance need to handoff to another aggregator when it leaves the subnets that make up its current aggregator�s service area (e.g., a hotspot or a cellular network).\ud In this paper, we present the design of a system that enables (multi-homed) mobile hosts to seamlessly handoff from one aggregator to another so that they can continue to receive a channel wherever they go. We concentrate on handoffs between aggregators as a result of a mobile host crossing a subnet boundary. As part of the system, we discuss a lightweight application-level protocol that enables mobile hosts to select the aggregator that provides the �best� configuration of a channel. The protocol comes into play when a mobile host begins to receive a channel and when it crosses a subnet boundary while receiving the channel. We show how our protocol can be implemented using the standard IETF session control and description protocols SIP and SDP. The implementation combines SIP and SDP�s offer-answer model in a novel way

Victim, perpetrator, family, and incident characteristics of infant and child homicide in the United States Air Force

Objective: The present study describes factors related to fatal abuse in three age groups in the United States Air Force (USAF). Method: Records from 32 substantiated cases of fatal child abuse in the USAF were independently reviewed for 60 predefined factors. Results: Males were over-represented in young child victims (between 1 year and 4 years of age) and child victims (between 4 years and 15 years of age) but not in infant victims (between 24 hours and 1 year of age). African-American infant victims and perpetrators were over-represented. Younger victims were more likely to have been previously physically abused by the perpetrator. Perpetrators were predominantly male and the biological fathers of the victims. Infant and young child perpetrators reported childhood abuse histories, while child perpetrators reported the highest frequency of mental health contact. Victims’ families reported significant life stressors. Families of young child victims were more likely divorced, separated, or single. Incidents with infants and young children tended to occur without witnesses; incidents with child victims tended to have the victim’s sibling(s) and/or mother present. Fatal incidents were more frequent on the weekend, in the home, and initiated by some family disturbance. Conclusions: Differences among groups in factors related to infant and child homicide across age groups may assist in the development of more tailored abuse prevention efforts and may also guide future investigations

LICSTER -- A Low-cost ICS Security Testbed for Education and Research

Unnoticed by most people, Industrial Control Systems (ICSs) control entire productions and critical infrastructures such as water distribution, smart grid and automotive manufacturing. Due to the ongoing digitalization, these systems are becoming more and more connected in order to enable remote control and monitoring. However, this shift bears significant risks, namely a larger attack surface, which can be exploited by attackers. In order to make these systems more secure, it takes research, which is, however, difficult to conduct on productive systems, since these often have to operate twenty-four-seven. Testbeds are mostly very expensive or based on simulation with no real-world physical process. In this paper, we introduce LICSTER, an open-source low-cost ICS testbed, which enables researchers and students to get hands-on experience with industrial security for about 500 Euro. We provide all necessary material to quickly start ICS hacking, with the focus on low-cost and open-source for education and research

Embodied Emotion Modulates Neural Signature of Performance Monitoring

BACKGROUND:Recent research on the "embodiment of emotion" implies that experiencing an emotion may involve perceptual, somatovisceral, and motor feedback aspects. For example, manipulations of facial expression and posture appear to induce emotional states and influence how affective information is processed. The present study investigates whether performance monitoring, a cognitive process known to be under heavy control of the dopaminergic system, is modulated by induced facial expressions. In particular, we focused on the error-related negativity, an electrophysiological correlate of performance monitoring. METHODS/PRINCIPAL FINDINGS:During a choice reaction task, participants held a Chinese chop stick either horizontally between the teeth ("smile" condition) or, in different runs, vertically ("no smile") with the upper lip. In a third control condition, no chop stick was used ("no stick"). It could be shown on a separate sample that the facial feedback procedure is feasible to induce mild changes in positive affect. In the ERP sample, the smile condition, hypothesized to lead to an increase in dopaminergic activity, was associated with a decrease of ERN amplitude relative to "no smile" and "no stick" conditions. CONCLUSION:Embodying emotions by induced facial expressions leads to a changes in the neural correlates of error detection. We suggest that this is due to the joint influence of the dopaminergic system on positive affect and performance monitoring

Two-dimensional infrared spectroscopy of photoswitchable peptides

We present a detailed discussion of the complimentary fields of the application of two-dimensional infrared (2D-IR) spectroscopy in comparison with two-dimensional nuclear magnetic resonance (2D-NMR) spectroscopy. Transient 2D-IR (T2D-IR) spectroscopy of nonequilibrium ensembles is probably one of the most promising strengths of 2D-IR spectroscopy, as the possibilities of 2D-NMR spectroscopy are limited in this regime. T2D-IR spectroscopy uniquely combines ultrafast time resolution with microscopic structural resolution. In this article we summarize our recent efforts to investigate the ultrafast structural dynamics of small peptides, such as the unfolding of peptide secondary structure motifs. The work requires two ingredients: 2D-IR spectroscopy and the possibility of triggering a structural transition of a peptide on an ultrafast timescale using embedded or intrinsic photoswitches. Several photoswitches have been tested, and we discuss our progress in merging these two pathways of research