Enabling heterogeneous network function chaining

Today's data center operators deploy network policies in both physical (e.g., middleboxes, switches) and virtualized (e.g., virtual machines on general purpose servers) network function boxes (NFBs), which reside in different points of the network, to exploit their efficiency and agility respectively. Nevertheless, such heterogeneity has resulted in a great number of independent network nodes that can dynamically generate and implement inconsistent and conflicting network policies, making correct policy implementation a difficult problem to solve. Since these nodes have varying capabilities, services running atop are also faced with profound performance unpredictability. In this paper, we propose a Heterogeneous netwOrk Policy Enforcement (HOPE) scheme to overcome these challenges. HOPE guarantees that network functions (NFs) that implement a policy chain are optimally placed onto heterogeneous NFBs such that the network cost of the policy is minimized. We first experimentally demonstrate that the processing capacity of NFBs is the dominant performance factor. This observation is then used to formulate the Heterogeneous Network Policy Placement problem, which is shown to be NP-Hard. To solve the problem efficiently, an online algorithm is proposed. Our experimental results demonstrate that HOPE achieves the same optimality as Branch-and-bound optimization but is 3 orders of magnitude more efficient

Layered Poly(3-hexylthiophene) Nanowhiskers Studied by Atomic Force Microscopy and Kelvin Probe Force Microscopy

The optoelectronic properties of organic electronic materials are significantly affected by their molecular packing and local environments. Herein, atomic force microscopy (AFM) is used to characterize nanowhiskers of poly­(3-hexylthiphene) (P3HT). The P3HT nanowhiskers form layered structures with distinctive heights that increase over time, suggesting that layered structures are more thermodynamically favored in solution. Further inspection reveals that the monolayer (ML) nanowhiskers are consistently wider than double-layered (DL) ones. The width disparity is likely due to the sliding of π–π stacked motifs within ML nanowhiskers evident by the rougher edges of ML nanowhiskers. Conversely, the interfacial interactions between two P3HT monolayers may inhibit the sliding of conjugated motifs inside the DL nanowhiskers, leading to much narrower and tightly packed structures. Kelvin probe force microscopy (KPFM) measurements are carried out to investigate the influence of ML and DL nanowhiskers’ morphologies and local environments on their electronic properties. Curved, vertically stacked, and overlapped regions show higher contact potential differences (CPD) resulting from a combined effect of irregular molecular packing and local environmental impacts

Room-Temperature Long-Lived Triplet Excited States of Naphthalenediimides and Their Applications as Organic Triplet Photosensitizers for Photooxidation and Triplet–Triplet Annihilation Upconversions

Naphthalenediimide (NDI) derivatives with 2,6- or 2,3,6,7-tetrabromo or amino substituents were prepared. <i>N</i>,<i>N′</i>-dialkyl-2,6-dibromo NDI (compound <b>2</b>) and <i>N</i>,<i>N′</i>-dialkyl-2,3,6,7-tetrabromo NDI (compound <b>4</b>) show phosphorescence emission at 610 or 667 nm, respectively. Phosphorescence was never observed for NDI derivatives. Conversely, <i>N</i>,<i>N′</i>-dialkyl-2,6-dibromo-3,7-diamino NDI (compound <b>5</b>) shows strong absorption at 526 nm and fluorescence at 551 nm, and no phosphorescence was observed. However, nanosecond time-resolved transient difference absorption spectroscopy confirmed that the triplet excited state of <b>5</b> was populated upon photoexcitation. 2,3,6,7-Tetraamino NDI (<b>6</b>) shows fluorescence, and no triplet excited state was populated upon excitation. The compounds were used as singlet oxygen (¹O₂) photosensitizers for the photooxidation of 1,5-dihydroxylnaphthalene (DHN). We found that <b>5</b> is more efficient than the conventional photosensitizer, such as Ir­(ppy)₂(bpy)­[PF₆]. The compounds were also used as organic triplet photosensitizers for triplet–triplet annihilation based upconversions. An upconversion quantum yield up to 18.5% was observed

Evolution of Human Longevity Uncoupled from Caloric Restriction Mechanisms

<div><p>Caloric restriction (CR) and chemical agents, such as resveratrol and rapamycin that partially mimic the CR effect, can delay morbidity and mortality across a broad range of species. In humans, however, the effects of CR or other life-extending agents have not yet been investigated systematically. Human maximal lifespan is already substantially greater compared to that of closely related primate species. It is therefore possible that humans have acquired genetic mutations that mimic the CR effect. Here, we tested this notion by comparing transcriptome differences between humans and other primates, with the transcriptome changes observed in mice subjected to CR. We show that the human transcriptome state, relative to other primate transcriptomes, does not match that of the CR mice or mice treated with resveratrol, but resembles the transcriptome state of <i>ad libitum</i> fed mice. At the same time, the transcriptome changes induced by CR in mice are enriched among genes showing age-related changes in primates, concentrated in specific expression patterns, and can be linked with specific functional pathways, including insulin signalling, cancer, and the immune response. These findings indicate that the evolution of human longevity was likely independent of CR-induced lifespan extension mechanisms. Consequently, application of CR or CR-mimicking agents may yet offer a promising direction for the extension of healthy human lifespan.</p></div

Light-Harvesting Fullerene Dyads as Organic Triplet Photosensitizers for Triplet–Triplet Annihilation Upconversions

Visible light-harvesting C₆₀–bodipy dyads were devised as universal organic triplet photosensitizers for triplet–triplet annihilation (TTA) upconversion. The antennas in the dyad were used to harvest the excitation energy, and then the singlet excited state of C₆₀ will be populated via the intramolecular energy transfer from the antenna to C₆₀ unit. In turn with the intrinsic intersystem crossing (ISC) of the C₆₀, the triplet excited state of the C₆₀ will be produced. Thus, without any heavy atoms, the triplet excited states of organic dyads are populated upon photoexcitation. Different from C₆₀, the dyads show strong absorption of visible light at 515 nm (<b>C-1</b>, ε = 70400 M^–1 cm^–1) or 590 nm (<b>C-2</b>, ε = 82500 M^–1 cm^–1). Efficient intramolecular energy transfer from the bodipy moieties to C₆₀ unit and localization of the triplet excited state on C₆₀ were confirmed by steady-state and time-resolved spectroscopy as well as DFT calculations. The dyads were used as triplet photosensitizers for TTA upconversion, and an upconversion quantum yield up to 7.0% was observed. We propose that C₆₀–organic chromophore dyads can be used as a general molecular structural motif for organic triplet photosensitizers, which can be used for photocatalysis, photodynamic therapy, and TTA upconversions

Time-shift between human and mouse expression profiles in the mTOR pathway.

<p>A: mTOR pathway gene expression curves of human and mouse prefrontal cortex. The x-axis shows log-transformed age from conception (“conception age”) values for both human and mouse, and the y-axis shows the normalized gene expression value. Each asterisk represents the mean expression value for a certain age point and horizontal bars represent the expression variance of genes within the mTOR pathway (only 42 of the 52 genes that showed substantial correlation (Pearson r>0.5) with the average pathway profile were included). B: Human-mouse time-shift. The x-axis shows the age from conception of mouse, and the y-axis shows the time-shift of human age relative to mouse age. Each asterisk represents the average time shift of genes within the mTOR pathway, and the bars show the variance of each time point. C: Scatter plot of human age plotted against mouse age according to the human-mouse time-shift values. The x- and y-axes show the age from conception of mouse and human, respectively. The red arrow indicates the point where human age equals 600 days of mouse age based on the time-shift calculation for the mTOR pathway genes.</p

Dataset information.

<p>Dataset information.</p

Bodipy Derivatives as Organic Triplet Photosensitizers for Aerobic Photoorganocatalytic Oxidative Coupling of Amines and Photooxidation of Dihydroxylnaphthalenes

We used iodo-Bodipy derivatives that show strong absorption of visible light and long-lived triplet excited states as organic catalysts for photoredox catalytic organic reactions. Conventionally most of the photocatalysts are based on the off-the-shelf compounds, usually showing weak absorption in the visible region and short triplet excited state lifetimes. Herein, the organic catalysts are used for two photocatalyzed reactions mediated by singlet oxygen (¹O₂), that is, the aerobic oxidative coupling of amines and the photooxidation of dihydroxylnaphthalenes, which is coupled to the subsequent addition of amines to the naphthoquinones, via C–H functionalization of 1,4-naphthoquinone, to produce <i>N</i>-aryl-2-amino-1,4-naphthoquinones (one-pot reaction), which are anticancer and antibiotic reagents. The photoreactions were substantially accelerated with these new iodo-Bodipy organic photocatalysts compared to that catalyzed with the conventional Ru­(II)/Ir­(III) complexes, which show weak absorption in the visible region and short-lived triplet excited states. Our results will inspire the design and application of new organic triplet photosensitizers that show strong absorption of visible light and long-lived triplet excited state and the application of these catalysts in photoredox catalytic organic reactions

Additional file 1: of Cilostazol induced migraine does not respond to sumatriptan in a double blind trial

Datasheet Cilostazol MO. (XLSX 25 kb

Use of the Stable Nitrogen Isotope to Reveal the Source-Sink Regulation of Nitrogen Uptake and Remobilization during Grain Filling Phase in Maize

<div><p>Although the remobilization of vegetative nitrogen (N) and post-silking N both contribute to grain N in maize (<i>Zea mays</i> L.), their regulation by grain sink strength is poorly understood. Here we use ¹⁵N labeling to analyze the dynamic behaviors of both pre- and post-silking N in relation to source and sink manipulation in maize plants. The results showed that the remobilization of pre-silking N started immediately after silking and the remobilized pre-silking N had a greater contribution to grain N during early grain filling, with post-silking N importance increasing during the later filling stage. The amount of post-silking N uptake was largely driven by post-silking dry matter accumulation in both grain as well as vegetative organs. Prevention of pollination during silking had less effect on post-silking N uptake, as a consequence of compensatory growth of stems, husk + cob and roots. Also, leaves continuously export N even though grain sink was removed. The remobilization efficiency of N in the leaf and stem increased with increasing grain yield (hence N requirement). It is suggested that the remobilization of N in the leaf is controlled by sink strength but not the leaf <i>per se</i>. Enhancing post-silking N uptake rather than N remobilization is more likely to increase grain N accumulation.</p></div