Saarland University

About: Saarland University is a education organization based out in Saarbrücken, Germany. It is known for research contribution in the topics: Population & Medicine. The organization has 19555 authors who have published 39678 publications receiving 1109295 citations. The organization is also known as: University of the Saarland & Universität des Saarlandes.

The oral microbiome – an update for oral healthcare professionals

Abstract: For millions of years, our resident microbes have coevolved and coexisted with us in a mostly harmonious symbiotic relationship. We are not distinct entities from our microbiome, but together we form a 'superorganism' or holobiont, with the microbiome playing a significant role in our physiology and health. The mouth houses the second most diverse microbial community in the body, harbouring over 700 species of bacteria that colonise the hard surfaces of teeth and the soft tissues of the oral mucosa. Through recent advances in technology, we have started to unravel the complexities of the oral microbiome and gained new insights into its role during both health and disease. Perturbations of the oral microbiome through modern-day lifestyles can have detrimental consequences for our general and oral health. In dysbiosis, the finely-tuned equilibrium of the oral ecosystem is disrupted, allowing disease-promoting bacteria to manifest and cause conditions such as caries, gingivitis and periodontitis. For practitioners and patients alike, promoting a balanced microbiome is therefore important to effectively maintain or restore oral health. This article aims to give an update on our current knowledge of the oral microbiome in health and disease and to discuss implications for modern-day oral healthcare.

Runtime measurements in the cloud: observing, analyzing, and reducing variance

Abstract: One of the main reasons why cloud computing has gained so much popularity is due to its ease of use and its ability to scale computing resources on demand. As a result, users can now rent computing nodes on large commercial clusters through several vendors, such as Amazon and rackspace. However, despite the attention paid by Cloud providers, performance unpredictability is a major issue in Cloud computing for (1) database researchers performing wall clock experiments, and (2) database applications providing service-level agreements. In this paper, we carry out a study of the performance variance of the most widely used Cloud infrastructure (Amazon EC2) from different perspectives. We use established microbenchmarks to measure performance variance in CPU, I/O, and network. And, we use a multi-node MapReduce application to quantify the impact on real dataintensive applications. We collected data for an entire month and compare it with the results obtained on a local cluster. Our results show that EC2 performance varies a lot and often falls into two bands having a large performance gap in-between --- which is somewhat surprising. We observe in our experiments that these two bands correspond to the different virtual system types provided by Amazon. Moreover, we analyze results considering different availability zones, points in time, and locations. This analysis indicates that, among others, the choice of availability zone also influences the performance variability. A major conclusion of our work is that the variance on EC2 is currently so high that wall clock experiments may only be performed with considerable care. To this end, we provide some hints to users.

Social risk management : a new conceptual framework for social protection and beyond

Abstract: This paper proposes a new definition, and conceptual framework for social protection, grounded in social risk management. The concept repositions the traditional areas of social protection (labor market intervention, social insurance, and social safety nets) in a framework that includes three strategies to deal with risk (prevention, mitigation, and coping), three levels of formality of risk management (informal, market-based, public), and, many actors (individuals, households, communities, non-governmental organizations, governments at various levels, and international organizations) against the background of asymmetric information, and different types of risk. This expanded view of social protection emphasizes the double role of risk management instruments - protecting basic livelihood, as well as promoting risk taking. It focuses specifically on the poor, since they are the most vulnerable to risk, and typically lack appropriate risk management instruments, which constrains them from engaging in riskier, but also higher return activities, and hence gradually moving out of chronic poverty.