Cybersecurity through Real-Time Distributed Control Systems

Critical infrastructure sites and facilities are becoming increasingly dependent on interconnected physical and cyber-based real-time distributed control systems (RTDCSs). A mounting cybersecurity threat results from the nature of these ubiquitous and sometimes unrestrained communications interconnections. Much work is under way in numerous organizations to characterize the cyber threat, determine means to minimize risk, and develop mitigation strategies to address potential consequences. While it seems natural that a simple application of cyber-protection methods derived from corporate business information technology (IT) domain would lead to an acceptable solution, the reality is that the characteristics of RTDCSs make many of those methods inadequate and unsatisfactory or even harmful. A solution lies in developing a defense-in-depth approach that ranges from protection at communications interconnect levels ultimately to the control system s functional characteristics that are designed to maintain control in the face of malicious intrusion. This paper summarizes the nature of RTDCSs from a cybersecurity perspec tive and discusses issues, vulnerabilities, candidate mitigation approaches, and metrics

Theoretically-Efficient and Practical Parallel DBSCAN

The DBSCAN method for spatial clustering has received significant attention due to its applicability in a variety of data analysis tasks. There are fast sequential algorithms for DBSCAN in Euclidean space that take $O(n\log n)$ work for two dimensions, sub-quadratic work for three or more dimensions, and can be computed approximately in linear work for any constant number of dimensions. However, existing parallel DBSCAN algorithms require quadratic work in the worst case, making them inefficient for large datasets. This paper bridges the gap between theory and practice of parallel DBSCAN by presenting new parallel algorithms for Euclidean exact DBSCAN and approximate DBSCAN that match the work bounds of their sequential counterparts, and are highly parallel (polylogarithmic depth). We present implementations of our algorithms along with optimizations that improve their practical performance. We perform a comprehensive experimental evaluation of our algorithms on a variety of datasets and parameter settings. Our experiments on a 36-core machine with hyper-threading show that we outperform existing parallel DBSCAN implementations by up to several orders of magnitude, and achieve speedups by up to 33x over the best sequential algorithms

Southern Ocean pteropods at risk from ocean warming and acidification

Early life stages of marine calcifiers are particularly vulnerable to climate change. In the Southern Ocean aragonite undersaturation events and areas of rapid warming already occur and are predicted to increase in extent. Here, we present the first study to successfully hatch the polar pteropod Limacina helicina antarctica and observe the potential impact of exposure to increased temperature and aragonite undersaturation resulting from ocean acidification (OA) on the early life stage survival and shell morphology. High larval mortality (up to 39%) was observed in individuals exposed to perturbed conditions. Warming and OA induced extensive shell malformation and dissolution, respectively, increasing shell fragility. Furthermore, shell growth decreased, with variation between treatments and exposure time. Our results demonstrate that short-term exposure through passing through hotspots of OA and warming poses a serious threat to pteropod recruitment and long-term population viability

Polymer and Carbon Spheres with an Embedded Shell of Plasmonic Gold Nanoparticles

Gold nanoparticle (AuNP)/resin nanosphere composites have been prepared in a novel process where the resin functions as both the host and reducing agent. Electron tomography showed that the AuNPs are organized into a concentric shell fully embedded in the resin nanospheres. Pyrolysis of the composite spheres afforded microporous N-doped carbon nanospheres with a pseudoshell of embedded AuNPs. These new composites with uncapped plasmonic nanoparticles have excellent potential for biomedical, catalysis, energy storage, and sensing applications

Polymer and Carbon Spheres with an Embedded Shell of Plasmonic Gold Nanoparticles

Gold nanoparticle (AuNP)/resin nanosphere composites have been prepared in a novel process where the resin functions as both the host and reducing agent. Electron tomography showed that the AuNPs are organized into a concentric shell fully embedded in the resin nanospheres. Pyrolysis of the composite spheres afforded microporous N-doped carbon nanospheres with a pseudoshell of embedded AuNPs. These new composites with uncapped plasmonic nanoparticles have excellent potential for biomedical, catalysis, energy storage, and sensing applications

REVIEW ARTICLES Obstructive sleep apnea and cardiovascular effects-a review

Obstructive sleep apnea (OSA) is the most common form of sleep-disordered breathing, affecting 5–15 % of the population. It is characterized by intermittent episodes of partial or complete obstruction of the upper airway during sleep that disrupts normal ventilation and sleep architecture, and is typically associated with excessive daytime sleepiness, snoring, and witnessed apneas. Patients with obstructive sleep apnea present risk to the general public safety by causing 8-fold increase in vehicle accidents, and they may themselves also suffer from the physiologic consequences of OSA; these include hypertension, coronary artery disease, stroke, congestive heart failure, pulmonary hypertension, and cardiac arrhythmias. Of these possible cardiovascular consequences, the association between OSA and hypertension has been found to be the most convincing. Although the exact mechanism has not been understood, there is some evidence that OSA is associated with frequent apneas causing mechanical effects on intrathoracic pressure, cardiac function, and intermittent hypoxemia, which may in turn cause endothelial dysfunction and increase in sympathetic drive. Therapy with continuous positive airway pressure has been demonstrated to improve cardiopulmonary hemodynamics in patients with OSA and may reverse the endothelial cell dysfunction. Limited availability of diagnostic measures and unawareness of physicians, many patients with OSA remain undiagnosed. Awareness and timely initiation of an effective treatment may prevent potential deleterious cardiovascular effects of OSA. Key words Obstructive Sleep apnea, Hypertension, Atherosclerosis, Continuous positive airway pressure

Polymer and Carbon Spheres with an Embedded Shell of Plasmonic Gold Nanoparticles

Gold nanoparticle (AuNP)/resin nanosphere composites have been prepared in a novel process where the resin functions as both the host and reducing agent. Electron tomography showed that the AuNPs are organized into a concentric shell fully embedded in the resin nanospheres. Pyrolysis of the composite spheres afforded microporous N-doped carbon nanospheres with a pseudoshell of embedded AuNPs. These new composites with uncapped plasmonic nanoparticles have excellent potential for biomedical, catalysis, energy storage, and sensing applications