Designed-in security for cyber-physical systems

An expert from academia, one from a cyber-physical system (CPS) provider, and one from an end asset owner and user offer their different perspectives on the meaning and challenges of 'designed-in security.' The academic highlights foundational issues and talks about emerging technology that can help us design and implement secure software in CPSs. The vendor's view includes components of the academic view but emphasizes the secure system development process and the standards that the system must satisfy. The user issues a call to action and offers ideas that will ensure progress

Coral Communities, in Contrast to Fish Communities, Maintain a High Assembly Similarity along the Large Latitudinal Gradient along the Saudi Red Sea Coast

The Saudi Arabian Red Sea coast is characterized by a strong environmental gradient from north (28.5°N) to south (16.5°N) with challenging conditions for coral growth particularly in the south (high temperature and nutrient input). We investigated whether assemblies of reef-building corals and the distribution of functional groups follow a latitudinal pattern in the Red Sea, and whether these changes affect the assembly structure of coral associated organisms (e.g. fishes). Functional groups were defined based on life-history traits and functional role. 13 reefs along the north-south gradient, including 5 potentially polluted reefs were investigated. Results showed a substantially weaker latitudinal shift in the assembly structure of coral communities than of fishes communities and of other benthic reef taxa. Competitive fast growing branching and tabular species (mainly Acropora), as well as rather stresstolerant slow growing bulky species (e.g. Porites, Goniastrea, Favites, Favia) were fairly evenly distributed along the north-south axis despite strong changes of environmental conditions. This seems on the one hand attributable to the high species richness within a given functional group (functional redundancy) and on the other hand to a high acclimatization / adaptation potential of some Red Sea coral species. The prime ecosystem service of the coral community, the provision of a habitat complex, is thereby maintained throughout the gradient. In contrast to the coral community, the assembly of the fish community shifts along the environmental gradient with higher abundances of small wrasses and butterfly fishes in the north, and overall higher abundance of fishes including large fishes in the south. This shift seems linked to higher food availability in the south. Altered assembly structures of coral communities were found in reefs close to a source of pollution with either an increased relative abundance of stresstolerant species or a general decrease of coral abundance, latter case accompanied by a substantial reduction in fish abundance

Response of foundation macrophytes to near‐natural simulated marine heatwaves

Marine heatwaves have been observed worldwide and are expected to increase in both frequency and intensity due to climate change. Such events may cause ecosystem reconfigurations arising from species range contraction or redistribution, with ecological, economic and social implications. Macrophytes such as the brown seaweed Fucus vesiculosus and the seagrass Zostera marina are foundation species in many coastal ecosystems of the temperate northern hemisphere. Hence, their response to extreme events can potentially determine the fate of associated ecosystems. Macrophyte functioning is intimately linked to the maintenance of photosynthesis, growth and reproduction, and resistance against pathogens, epibionts and grazers. We investigated morphological, physiological, pathological and chemical defence responses of western Baltic Sea F. vesiculosus and Z. marina populations to simulated near‐natural marine heatwaves. Along with (a) the control, which constituted no heatwave but natural stochastic temperature variability (0HW), two treatments were applied: (b) two late‐spring heatwaves (June, July) followed by a summer heatwave (August; 3HW) and (c) a summer heatwave only (1HW). The 3HW treatment was applied to test whether preconditioning events can modulate the potential sensitivity to the summer heatwave. Despite the variety of responses measured in both species, only Z. marina growth was impaired by the accumulative heat stress imposed by the 3HW treatment. Photosynthetic rate, however, remained high after the last heatwave indicating potential for recovery. Only epibacterial abundance was significantly affected in F. vesiculosus. Hence both macrophytes, and in particular F. vesiculosus, seem to be fairly tolerant to short‐term marine heatwaves at least at the intensities applied in this experiment (up to 5°C above mean temperature over a period of 9 days). This may partly be due to the fact that F. vesiculosus grows in a highly variable environment, and may have a high phenotypic plasticit

Urban coral reefs: Degradation and resilience of hard coral assemblages in coastal cities of East and Southeast Asia

© 2018 The Author(s) Given predicted increases in urbanization in tropical and subtropical regions, understanding the processes shaping urban coral reefs may be essential for anticipating future conservation challenges. We used a case study approach to identify unifying patterns of urban coral reefs and clarify the effects of urbanization on hard coral assemblages. Data were compiled from 11 cities throughout East and Southeast Asia, with particular focus on Singapore, Jakarta, Hong Kong, and Naha (Okinawa). Our review highlights several key characteristics of urban coral reefs, including “reef compression” (a decline in bathymetric range with increasing turbidity and decreasing water clarity over time and relative to shore), dominance by domed coral growth forms and low reef complexity, variable city-specific inshore-offshore gradients, early declines in coral cover with recent fluctuating periods of acute impacts and rapid recovery, and colonization of urban infrastructure by hard corals. We present hypotheses for urban reef community dynamics and discuss potential of ecological engineering for corals in urban areas

Coral microbiome composition along the northern Red Sea suggests high plasticity of bacterial and specificity of endosymbiotic dinoflagellate communities

Background The capacity of reef-building corals to tolerate (or adapt to) heat stress is a key factor determining their resilience to future climate change. Changes in coral microbiome composition (particularly for microalgal endosymbionts and bacteria) is a potential mechanism that may assist corals to thrive in warm waters. The northern Red Sea experiences extreme temperatures anomalies, yet corals in this area rarely bleach suggesting possible refugia to climate change. However, the coral microbiome composition, and how it relates to the capacity to thrive in warm waters in this region, is entirely unknown. Results We investigated microbiomes for six coral species (Porites nodifera, Favia favus, Pocillopora damicornis, Seriatopora hystrix, Xenia umbellata, and Sarcophyton trocheliophorum) from five sites in the northern Red Sea spanning 4° of latitude and summer mean temperature ranges from 26.6 °C to 29.3 °C. A total of 19 distinct dinoflagellate endosymbionts were identified as belonging to three genera in the family Symbiodiniaceae (Symbiodinium, Cladocopium, and Durusdinium). Of these, 86% belonged to the genus Cladocopium, with notably five novel types (19%). The endosymbiont community showed a high degree of host-specificity despite the latitudinal gradient. In contrast, the diversity and composition of bacterial communities of the surface mucus layer (SML)—a compartment particularly sensitive to environmental change—varied significantly between sites, however for any given coral was species-specific. Conclusion The conserved endosymbiotic community suggests high physiological plasticity to support holobiont productivity across the different latitudinal regimes. Further, the presence of five novel algal endosymbionts suggests selection of certain genotypes (or genetic adaptation) within the semi-isolated Red Sea. In contrast, the dynamic composition of bacteria associated with the SML across sites may contribute to holobiont function and broaden the ecological niche. In doing so, SML bacterial communities may aid holobiont local acclimatization (or adaptation) by readily responding to changes in the host environment. Our study provides novel insight about the selective and endemic nature of coral microbiomes along the northern Red Sea refugia

The retrobulbar sinus is superior to the lateral tail vein for the injection of contrast media in small animal cardiac imaging

Cardiac perfusion studies using computed tomography are a common tool in clinical practice. Recent technical advances and the availability of dedicated small animal scanners allow the transfer of these techniques to the preclinical sector in general and to mouse models of cardiac diseases in particular. This necessitates new requirements for contrast injection techniques as a rapid transport of contrast media from the intravenous access to the animal heart. Clinical contrast agents containing high iodine concentrations are used within small animal studies although they exhibit a high viscosity which might limit their transport within the vasculature. The authors provide a comparison of the transport of contrast media following an injection into the lateral tail vein and an injection into the retrobulbar sinus and discuss the anatomy involved. The temporal evolution of a contrast bolus and its in vivo distribution is visualized. It is demonstrated that injecting contrast agents into the lateral tail vein of mice results in a retrograde blood flow to the liver veins and therefore does not deliver a detectable contrast bolus to the heart, and thus it cannot be used for cardiac perfusion studies. By contrast, boli injected into the retrobulbar sinus are rapidly transported to the heart and provide ventricular contrast enabling perfusion studies similar to those in human patients. The results demonstrate that an injection into the retrobulbar sinus is superior to an injection into the lateral tail vein for the delivery of contrast boli to the animal heart, while all drawbacks of an injection into the lateral tail vein are overcome

Designed-in security for cyber-physical systems

An expert from academia, one from a cyber-physical system (CPS) provider, and one from an end asset owner and user offer their different perspectives on the meaning and challenges of 'designed-in security.' The academic highlights foundational issues and talks about emerging technology that can help us design and implement secure software in CPSs. The vendor's view includes components of the academic view but emphasizes the secure system development process and the standards that the system must satisfy. The user issues a call to action and offers ideas that will ensure progress

Metabolic rates and tissue composition of the coral Pocillopora verrucosa over 12 latitudes in the Red Sea characterized by strong temperature and nutrient gradient

Global warming was reported to cause growth reductions in tropical shallow water corals in both, cooler and warmer, regions of the coral species range. This suggests regional adaptation with less heat-tolerant populations in cooler and more thermo-tolerant populations in warmer regions. Here, we investigated seasonal changes in the in situ metabolic performance of the widely distributed hermatypic coral Pocillopora verrucosa along 12 degrees latitudes featuring a steep temperature gradient between the northern (28.5 degrees N, 21-27 degrees C) and southern (16.5 degrees N, 28-33 degrees C) reaches of the Red Sea. Surprisingly, we found little indication for regional adaptation, but strong indications for high phenotypic plasticity: Calcification rates in two seasons (winter, summer) were found to be highest at 28-29 degrees C throughout all populations independent of their geographic location. Mucus release increased with temperature and nutrient supply, both being highest in the south. Genetic characterization of the coral host revealed low inter-regional variation and differences in the Symbiodinium clade composition only at the most northern and most southern region. This suggests variable acclimatization potential to ocean warming of coral populations across the Red Sea: high acclimatization potential in northern populations, but limited ability to cope with ocean warming in southern populations already existing at the upper thermal margin for coral