Module Graph Merging and Placement to Reduce Reconfiguration Overheads in Paged FPGA Devices

Reconfiguration time in dynamically-reconfigurable modular systems can severely limit application run-time compared to the critical path delay. In this paper we present a novel method to reduce reconfiguration time by maximising wire use and minimising wire reconfiguration. This builds upon our previously-presented methodology for creating modular, dynamically-reconfigurable applications targeted to an FPGA. The application of our techniques is demonstrated on an optical flow problem and show that graph merging can reduce reconfiguration delay by 50%. 1

Universal State Transfer on Graphs

A continuous-time quantum walk on a graph $G$ is given by the unitary matrix $U(t) = \exp(-itA)$, where $A$ is the Hermitian adjacency matrix of $G$. We say $G$ has pretty good state transfer between vertices $a$ and $b$ if for any $\epsilon > 0$, there is a time $t$, where the $(a,b)$-entry of $U(t)$ satisfies $|U(t)_{a,b}| \ge 1-\epsilon$. This notion was introduced by Godsil (2011). The state transfer is perfect if the above holds for $\epsilon = 0$. In this work, we study a natural extension of this notion called universal state transfer. Here, state transfer exists between every pair of vertices of the graph. We prove the following results about graphs with this stronger property: (1) Graphs with universal state transfer have distinct eigenvalues and flat eigenbasis (where each eigenvector has entries which are equal in magnitude). (2) The switching automorphism group of a graph with universal state transfer is abelian and its order divides the size of the graph. Moreover, if the state transfer is perfect, then the switching automorphism group is cyclic. (3) There is a family of prime-length cycles with complex weights which has universal pretty good state transfer. This provides a concrete example of an infinite family of graphs with the universal property. (4) There exists a class of graphs with real symmetric adjacency matrices which has universal pretty good state transfer. In contrast, Kay (2011) proved that no graph with real-valued adjacency matrix can have universal perfect state transfer. We also provide a spectral characterization of universal perfect state transfer graphs that are switching equivalent to circulants.Comment: 27 pages, 3 figure

Recruitment, growth and mortality of an Antarctic hexactinellid sponge, Anoxycalyx joubini.

Polar ecosystems are sensitive to climate forcing, and we often lack baselines to evaluate changes. Here we report a nearly 50-year study in which a sudden shift in the population dynamics of an ecologically important, structure-forming hexactinellid sponge, Anoxycalyx joubini was observed. This is the largest Antarctic sponge, with individuals growing over two meters tall. In order to investigate life history characteristics of Antarctic marine invertebrates, artificial substrata were deployed at a number of sites in the southern portion of the Ross Sea between 1967 and 1975. Over a 22-year period, no growth or settlement was recorded for A. joubini on these substrata; however, in 2004 and 2010, A. joubini was observed to have settled and grown to large sizes on some but not all artificial substrata. This single settlement and growth event correlates with a region-wide shift in phytoplankton productivity driven by the calving of a massive iceberg. We also report almost complete mortality of large sponges followed over 40 years. Given our warming global climate, similar system-wide changes are expected in the future

Mitochondrial DNA methylation is associated with Mediterranean diet adherence in a population of older adults with overweight and obesity.

AbstractIntroductionAdherence to the Mediterranean dietary pattern (MeDiet) and adiposity, respectively, decreases and increases the risk of multiple common age-related diseases through several mechanisms including inflammation, reactive oxygen species (ROS) production in the mitochondria, and DNA methylation. For example, adverse changes in platelets from obese and overweight adults include hyperaggregability and increased ROS. Since platelets are anuclear, their prothrombotic function is fully orchestrated by the mitochondria and the only DNA present is the mitochondrial DNA (mtDNA). In this study, we tested the hypothesis that MeDiet influences patterns of mtDNA methylation in platelets from older adults with greater adiposity.Material and methodsWe selected 134 participants with overweight or obesity (mean BMI = 35.5 ± 5.1 and age = 62 ± 10 years) from the "Susceptibility to particle health effects, miRNA and exosomes"(SPEHRE) Study. Dietary intake was assessed using a food frequency questionnaire and MeDiet adherence was calculated using the MeDiet Score described by Martínez-González et al.(2012). MtDNA was extracted from platelets, linearized, bisulfite converted and DNA methylation was quantified by pyrosequencing at 13 CpG in seven genes that encode for tRNAs (MT-TF and MT-TL1), regulatory regions (D-Loop and MT-OLR), and subunits of the electron-transport-chain (MT-CO1, MT-CO2, and MT-CO3).ResultsIn these participants, MeDiet score ranged from 3 to 12 (mean = 6.5), with higher scores reflecting greater MeDiet adherence. Regression analysis showed that higher MeDiet score was associated with lower D-loop (β = -0.031, P = 0.019) and higher MT-CO2 CpG1 (β = 0.040, P = 0.023) methylation. No associations were found between MeDiet Score and methylation level at MT-CO1(2 CpGs), MT-CO2(CpG2), MT-CO3(2 CpGs), MT-TL1(2 CpGs), MT-TF(CpG1), MT-OLR(3 CpGs).In addition, there was no association between mtDNA methylation and BMI.DiscussionThe D-loop is critical for mitochondrial function since it initiates mtDNA replication and transcription. Increased D-loop methylation has been associated with reduced mitochondrial functionality, and insulin resistance. Our results suggest that higher adherence to MeDiet lowers D-loop methylation which may protect against obesity-related comorbidities (e.g. insulin resistance).Higher MeDiet scores are associated with MT-CO2 CpG1 hypermethylation. MT-CO2 encodes for a subunit of the Cytochrome-C-oxidase, a highly regulated enzyme involved in the oxidative metabolism. MT-CO2 demethylation, induced by Valproic-Acid administration, has been reported to be associated with increased ROS production. Our results suggest a possible role of MeDiet in mitochondrial ROS regulation via methylation of MT-CO2.For the first time, we observed associations between MeDiet adherence and mtDNA methylation. Validation of these findings in independent cohorts is required

Dietary nitrate and population health: a narrative review of the translational potential of existing laboratory studies

BACKGROUND: Dietary inorganic nitrate (NO(3)(−)) is a polyatomic ion, which is present in large quantities in green leafy vegetables and beetroot, and has attracted considerable attention in recent years as a potential health-promoting dietary compound. Numerous small, well-controlled laboratory studies have reported beneficial health effects of inorganic NO(3)(−) consumption on blood pressure, endothelial function, cerebrovascular blood flow, cognitive function, and exercise performance. Translating the findings from small laboratory studies into ‘real-world’ applications requires careful consideration. MAIN BODY: This article provides a brief overview of the existing empirical evidence basis for the purported health-promoting effects of dietary NO(3)(−) consumption. Key areas for future research are then proposed to evaluate whether promising findings observed in small animal and human laboratory studies can effectively translate into clinically relevant improvements in population health. These proposals include: 1) conducting large-scale, longer duration trials with hard clinical endpoints (e.g. cardiovascular disease incidence); 2) exploring the feasibility and acceptability of different strategies to facilitate a prolonged increase in dietary NO(3)(−) intake; 3) exploitation of existing cohort studies to explore associations between NO(3)(−) intake and health outcomes, a research approach allowing larger samples sizes and longer duration follow up than is feasible in randomised controlled trials; 4) identifying factors which might account for individual differences in the response to inorganic NO(3)(−) (e.g. sex, genetics, habitual diet) and could assist with targeted/personalised nutritional interventions; 5) exploring the influence of oral health and medication on the therapeutic potential of NO(3)(−) supplementation; and 6) examining potential risk of adverse events with long term high- NO(3)(−) diets. CONCLUSION: The salutary effects of dietary NO(3)(−) are well established in small, well-controlled laboratory studies. Much less is known about the feasibility and efficacy of long-term dietary NO(3)(−) enrichment for promoting health, and the factors which might explain the variable responsiveness to dietary NO(3)(−) supplementation between individuals. Future research focussing on the translation of laboratory data will provide valuable insight into the potential applications of dietary NO(3)(−) supplementation to improve population health

NuBrain: UK consortium for optimal nutrition for healthy brain ageing

With an ageing global population, there is an urgent need to identify effective strategies to maintain brain health across the life course and therein minimise the risk of age‐related neurodegenerative disorders reaching a severe stage which may manifest as dementia. An increasing body of evidence indicates that nutrition is a modifiable lifestyle factor that can promote healthy brain ageing and reduce dementia risk. However, at present, little is known about which dietary patterns, foods and food bioactives influence brain function during ageing, and more research is required to identify at‐risk individuals and population subgroups who are most likely to benefit from future nutritional intervention intended to promote healthier brain ageing. This article introduces the newly established Medical Research Council‐funded NuBrain consortium, the vision of which is to provide a step change in research in the area by developing novel approaches and techniques to further understand the complex interactions between diet and brain health and how we can support appropriate behaviour changes in the population. NuBrain will form a new, sustainable and internationally field‐leading research consortium with multidisciplinary and complementary areas of expertise to address the fundamental research challenges in this area