Detection of Bacterial Membrane Vesicles by NOD-Like Receptors

Bacterial membrane vesicles (BMVs) are nanoparticles produced by both Gram-negative and Gram-positive bacteria that can function to modulate immunity in the host. Both outer membrane vesicles (OMVs) and membrane vesicles (MVs), which are released by Gram-negative and Gram-positive bacteria, respectively, contain cargo derived from their parent bacterium, including immune stimulating molecules such as proteins, lipids and nucleic acids. Of these, peptidoglycan (PG) and lipopolysaccharide (LPS) are able to activate host innate immune pattern recognition receptors (PRRs), known as NOD-like receptors (NLRs), such as nucleotide-binding oligomerisation domain-containing protein (NOD) 1, NOD2 and NLRP3. NLR activation is a key driver of inflammation in the host, and BMVs derived from both pathogenic and commensal bacteria have been shown to package PG and LPS in order to modulate the host immune response using NLR-dependent mechanisms. Here, we discuss the packaging of immunostimulatory cargo within OMVs and MVs, their detection by NLRs and the cytokines produced by host cells in response to their detection. Additionally, commensal derived BMVs are thought to shape immunity and contribute to homeostasis in the gut, therefore we also highlight the interactions of commensal derived BMVs with NLRs and their roles in limiting inflammatory diseases.     

Characterizing Energy Usage of a Commercially Available Ground Robot: Method and Results

Energy usage by mobile robots is becoming a larger concern as autonomous systems increase mission durations. Understanding and characterizing energy usage is key to reliable mission operation. This paper presents a methodology for characterizing energy usage of a ground robot traveling at a constant speed applicable to both open and “black box” (proprietary) platforms. To address testing area limitations, we introduce a “rounded box” path to approximate straight line travel. For a case study, this methodology was applied to an iRobot Packbot on grass and asphalt surfaces. Our results show a decrease in electrical energy used with increasing speed for soft grass and constant energy usage on asphalt. For both surfaces, a similar electrical‐to‐mechanical efficiency curve is obtained.     

Multi swarms for neighbor selection in peer-to-peer overlay networks

Peer-to-peer (P2P) topology has a significant influence on the performance, search efficiency and functionality, and scalability of the application. In this paper, we investigate a multi-swarm approach to the problem of neighbor selection (NS) in P2P networks. Particle swarm share some common characteristics with P2P in the dynamic socially environment. Each particle encodes the upper half of the peer-connection matrix through the undirected graph, which reduces the search space dimension. The portion of the adjustment to the velocity influenced by the individual’s cognition, the group cognition from multi-swarms, and the social cognition from the whole swarm, makes an important influence on the particles’ ergodic and synergetic performance. We also attempt to theoretically prove that the multi-swarm optimization algorithm converges with a probability of 1 towards the global optima. The performance of our approach is evaluated and compared with other two different algorithms. The results indicate that it usually required shorter time to obtain better results than the other considered methods, specially for large scale problems.     

Measures of Population Ageing in Australia from 1950 to 2050

This study utilises annual historic and forecasted population figures from the UN World Population Prospects (2015 Revision) to describe Australia’s population changes for the period 1950–2050. A number of population indices have been employed to describe these changes. Specifically, we constructed population pyramids and computed measures including economic dependency ratios, support ratios, ageing/Billeter indices and coefficients of inflow, outflow and exchange of productive populations. Our results suggest that a combination of factors including declining fertility and mortality have contributed to Australia’s ageing population. The implications of these changes are broad and raise major challenges for Australia’s economy and infrastructure. To tackle both the drivers and impacts of population ageing, multi-faceted approaches are needed together with prompt evaluation to ensure that current and future challenges posed by population changes in Australia are fully contained.     

Goal adjustment capacities, coping, and subjective well-being: The sample case of caregiving for a family member with mental illness.

This study examined the associations between goal adjustment capacities, coping, and indicators of subjective well-being in 2 waves of data from individuals who provide care for a family member with mental illness. We hypothesized that goal adjustment capacities would predict higher levels of subjective well-being by facilitating coping with caregiving stress. Results showed that goal disengagement was associated with effective care-specific coping (e.g., less self-blame and substance use). Goal reengagement was also associated with effective care-specific coping (e.g., positive reframing), but at the same time it predicted the use of less effective strategies (e.g., venting and self-distraction). Moreover, goal disengagement predicted lower levels of caregiver burden and depressive symptoms and buffered the longitudinal effect of caregiver burden on increases in depressive symptoms. Goal reengagement, by contrast, predicted higher levels of caregiver burden and purpose in life and buffered the cross-sectional association between caregiver burden and depressive symptoms. Finally, effective (and less useful) care-specific coping statistically explained the adaptive (and maladaptive) effects of goal adjustment capacities on participants' well-being. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Changes in health care costs before and after smoking cessation.

Previous research on health care costs among former smokers suggests that quitters incur greater health care costs for up to 4 years after cessation compared with continuing smokers. However, little is known about the relationship between health care costs and utilization in the periods before as well as after cessation. The present study used a retrospective cohort design with automated health plan and primary data to examine the health care costs and clinical experiences before and after smoking cessation among former smokers compared with a sample of continuing smokers. Subjects were a random sample of adults (aged 25 and older) whose smoking status was identified by a physician during a primary care visit to the Group Health Cooperative (GHC), a nonprofit, integrated health care delivery system in western Washington state. Total direct health care costs among former smokers began to rise in the quarter prior to cessation and were significantly greater (p < .001) than those of continuing smokers in the quarter immediately following cessation. This difference dissipated within one quarter following cessation. We replicated the postquit cost spike among former smokers found by other research and showed that this spike dissipated within the first year postquit. Smoking cessation did not result in sustained cost increases among former smokers.