PLAN: Joint policy- and network-aware VM management for cloud data centers

Policies play an important role in network configuration and therefore in offering secure and high performance services especially over multi-tenant Cloud Data Center (DC) environments. At the same time, elastic resource provisioning through virtualization often disregards policy requirements, assuming that the policy implementation is handled by the underlying network infrastructure. This can result in policy violations, performance degradation and security vulnerabilities. In this paper, we define PLAN, a PoLicy-Aware and Network-aware VM management scheme to jointly consider DC communication cost reduction through Virtual Machine (VM) migration while meeting network policy requirements. We show that the problem is NP-hard and derive an efficient approximate algorithm to reduce communication cost while adhering to policy constraints. Through extensive evaluation, we show that PLAN can reduce topology-wide communication cost by 38 percent over diverse aggregate traffic and configuration policies

Comment on "Carnot efficiency at divergent power output" (and additional discussion)

In a recent Letter [EPL, 118 (2017) 40003], Polettini and Esposito claimed that it is theoretically possible for a thermodynamic machine to achieve Carnot efficiency at divergent power output through the use of infinitely-fast processes. It appears however that this assertion is misleading as it is not supported by their derivations as demonstrated below. In this Comment, we first show that there is a confusion regarding the notion of optimal efficiency. We then analyze the quantum dot engine described in Ref. [EPL, 118 (2017) 40003] and demonstrate that Carnot efficiency is recovered only for vanishing output power. Moreover, a discussion on the use of infinite thermodynamical forces to reach Carnot efficiency is also presented in the appendix.Comment: Modified version compared to the manuscript submitted to EP

Loss of Cardioprotective Effects at the ADAMTS7 Locus as a Result of Gene-Smoking Interactions

BACKGROUND: Common diseases such as coronary heart disease (CHD) are complex in etiology. The interaction of genetic susceptibility with lifestyle factors may play a prominent role. However, gene-lifestyle interactions for CHD have been difficult to identify. Here, we investigate interaction of smoking behavior, a potent lifestyle factor, with genotypes that have been shown to associate with CHD risk. METHODS: We analyzed data on 60 919 CHD cases and 80 243 controls from 29 studies for gene-smoking interactions for genetic variants at 45 loci previously reported to be associated with CHD risk. We also studied 5 loci associated with smoking behavior. Study-specific gene-smoking interaction effects were calculated and pooled using fixed-effects meta-analyses. Interaction analyses were declared to be significant at a P value of <1.0x10(-3) (Bonferroni correction for 50 tests). RESULTS: We identified novel gene-smoking interaction for a variant upstream of the ADAMTS7 gene. Every T allele of rs7178051 was associated with lower CHD risk by 12% in never-smokers (P= 1.3x10(-16)) in comparison with 5% in ever-smokers (P= 2.5x10(-4)), translating to a 60% loss of CHD protection conferred by this allelic variation in people who smoked tobacco (interaction P value= 8.7x10(-5)). The protective T allele at rs7178051 was also associated with reduced ADAMTS7 expression in human aortic endothelial cells and lymphoblastoid cell lines. Exposure of human coronary artery smooth muscle cells to cigarette smoke extract led to induction of ADAMTS7. CONCLUSIONS: Allelic variation at rs7178051 that associates with reduced ADAMTS7 expression confers stronger CHD protection in never-smokers than in ever-smokers. Increased vascular ADAMTS7 expression may contribute to the loss of CHD protection in smokers.Peer reviewe

Four-Wave Mixing Measurement of Third-Order Nonlinear Susceptibilities of Length-Sorted Single-Walled Carbon Nanotubes

The third-order nonlinear resonant electronic and Raman susceptibilities of length-sorted DNA-encased single-walled carbon nanotubes have been measured by the interferometric method of nondegenerate four-wave mixing spectroscopy. The four-wave mixing is predominantly resonant with the first interband transition E₁₁ of (10,5) nanotubes at 1275 nm. Large electronic third-order susceptibilities have been determined with a real part χ_Re⁽³⁾ = −3.0 × 10⁻⁸ esu and an imaginary part χ_Im⁽³⁾ = 2.9 × 10⁻⁸ esu. The G band Raman third-order susceptibility was simultaneously determined with a large value of χ⁽³⁾ = 3.3 × 10⁻⁸ esu, or 4.1 × 10⁻¹² esu per six-membered aromatic ring, which is ∼60 times larger that of 992 cm⁻¹ benzene ring breathing mode. Such large χ⁽³⁾ values suggest promising carbon nanotube applications in photonics and optical sensing

Size and linear growth rate of tail length of male and female <i>Phrynocephalus przewalskii</i> in Alax Zuoqi, China.

<p>The data are presented as means ±SE. The black circles represent male lizards and the open circles represent female lizards. Asterisks indicate significant size differences (a, ANCOVA with the SVL as covariate; b, ANOVA; ** <i>P</i><0.01; * <i>P</i><0.05).</p

Logistic growth curves for snout-vent length of male and female <i>P. przewalskii</i> in Alax Zuoqi, China.

<p>Months represent time spent growing (actual age minus 5 months of dormancy). Individual lizards occur more than once in this figure and hatching is assumed to have occurred in August. The continuous line represents male lizards and the dotted line represent female lizards.</p

Size and linear growth rate of hindlimb length of male and female <i>Phrynocephalus przewalskii</i> in Alax Zuoqi, China.

<p>The data are presented as means ±SE. The black circles represent male lizards and the open circles represent female lizards. Asterisks indicate significant size differences (a, ANCOVA with the SVL as covariate; b, ANOVA; ** <i>P</i><0.01; * <i>P</i><0.05).</p

Parameters of the differential forms of the logistic, Gompertz and Von Bertalanffy growth madels for male and female <i>Phrynocephalus przewalskii</i> at Alax Zuoqi, China during the period 2008–2010.

<p>Probabilities show the significance of the Pearson correlation coefficients for each equation. N, sample size; R², coefficient of determination; SGR, specific growth rate; SVL, snout-went length.</p

Size and linear growth rate of snout-vent length of male and female <i>Phrynocephalus przewalskii</i> in Alax Zuoqi, China.

<p>The data are presented as means ±SE. The black circles represent male lizards and the open circles represent female lizards. Data were collected using mark-recapture methods and the lizards were accurately aged from the month that they were first captured as hatchlings or early yearlings. Those larger than 2 years old when they first captured were eliminated. Individual lizards occur more than once in this figure and hatching was assumed to have occurred in August. Cohorts that hatched in different years are combined. Months represent the time spent growing (April–October), not actual ages. Lettering above the axis indicates the census date (month). Asterisks indicate significant size differences (a, ANOVA; b, ANCOVA with the mean SVL of initial and final capture as covariate; ** <i>P</i><0.01; * <i>P</i><0.05).</p