Reconfiguration on sparse graphs

A vertex-subset graph problem Q defines which subsets of the vertices of an input graph are feasible solutions. A reconfiguration variant of a vertex-subset problem asks, given two feasible solutions S and T of size k, whether it is possible to transform S into T by a sequence of vertex additions and deletions such that each intermediate set is also a feasible solution of size bounded by k. We study reconfiguration variants of two classical vertex-subset problems, namely Independent Set and Dominating Set. We denote the former by ISR and the latter by DSR. Both ISR and DSR are PSPACE-complete on graphs of bounded bandwidth and W[1]-hard parameterized by k on general graphs. We show that ISR is fixed-parameter tractable parameterized by k when the input graph is of bounded degeneracy or nowhere-dense. As a corollary, we answer positively an open question concerning the parameterized complexity of the problem on graphs of bounded treewidth. Moreover, our techniques generalize recent results showing that ISR is fixed-parameter tractable on planar graphs and graphs of bounded degree. For DSR, we show the problem fixed-parameter tractable parameterized by k when the input graph does not contain large bicliques, a class of graphs which includes graphs of bounded degeneracy and nowhere-dense graphs

Lack of cardioprotection from subcutaneously and preischemic administered Liraglutide in a closed chest porcine ischemia reperfusion model

<p>Abstract</p> <p>Background</p> <p>Glucagon-like peptide 1 (GLP1) analogues are promising new treatment options for patients with type 2 diabetes, but may have both potentially beneficial and harmful cardiovascular effects. This may also be the case for the analogues of GLP1 for clinical use. The present study examined the effect of treatment with Liraglutide, a long-acting GLP1 analogue, on myocardial ischemia and reperfusion in a porcine model.</p> <p>Methods</p> <p>Danish Landrace Pigs (70–80 kg) were randomly assigned to Liraglutide (10 μg/kg) or control treatment given daily for three days before ischemia-reperfusion. Ischemia was induced by balloon occlusion of the left anterior descending artery for 40 minutes followed by 2.5 hours of reperfusion. The primary outcome parameter was infarct size in relation to the ischemic region at risk. Secondary endpoints were the hemodynamic parameters mean pulmonary pressure, cardiac output, pulmonary capillary wedge pressure as measured by a Swan-Ganz catheter as well as arterial pressure and heart rate.</p> <p>Results</p> <p>The infarct size in relation to ischemic risk region in the control versus the Liraglutide group did not differ significantly: 0.46 ± 0.14 and 0.54 ± 0.12) (mean and standard deviation (SD), p = 0.21). Heart rate was significantly higher in the Liraglutide group during the experiment, while the other hemodynamic parameters did not differ significantly.</p> <p>Conclusion</p> <p>Liraglutide has a neutral effect on myocardial infarct size in a porcine ischemia-reperfusion model.</p

Sabotage in Contests: A Survey

A contest is a situation in which individuals expend irretrievable resources to win valuable prize(s). ‘Sabotage’ is a deliberate and costly act of damaging a rival’s' likelihood of winning the contest. Sabotage can be observed in, e.g., sports, war, promotion tournaments, political or marketing campaigns. In this article, we provide a model and various perspectives on such sabotage activities and review the economics literature analyzing the act of sabotage in contests. We discuss the theories and evidence highlighting the means of sabotage, why sabotage occurs, and the effects of sabotage on individual players and on overall welfare, along with possible mechanisms to reduce sabotage. We note that most sabotage activities are aimed at the ablest player, the possibility of sabotage reduces productive effort exerted by the players, and sabotage may lessen the effectiveness of public policies, such as affirmative action, or information revelation in contests. We discuss various policies that a designer may employ to counteract sabotage activities. We conclude by pointing out some areas of future research

Interface Effects on Attenuation and Phase Velocities in Metal-Matrix Composites

One often determines the effective elastic moduli and damping of a heterogeneous material by using elastic waves (propagating or standing). Several theoretical studies show that for long wavelengths one can calculate the effective wave speeds of plane longitudinal and shear waves through a composite material. At long wavelengths the wave speeds thus calculated are nondispersive and hence provide the values for the static effective elastic properties. References to some of the recent theoretical and experimental studies can be found in [1–12]. The scattering formulations developed in [1–8] provide a means to obtain both the effective wave speeds and the damping caused by scattering

Topologically Protected Quantum State Transfer in a Chiral Spin Liquid

Topology plays a central role in ensuring the robustness of a wide variety of physical phenomena. Notable examples range from the robust current carrying edge states associated with the quantum Hall and the quantum spin Hall effects to proposals involving topologically protected quantum memory and quantum logic operations. Here, we propose and analyze a topologically protected channel for the transfer of quantum states between remote quantum nodes. In our approach, state transfer is mediated by the edge mode of a chiral spin liquid. We demonstrate that the proposed method is intrinsically robust to realistic imperfections associated with disorder and decoherence. Possible experimental implementations and applications to the detection and characterization of spin liquid phases are discussed.Comment: 14 pages, 7 figure

Why are thoracic operations postponed?

<p>Abstract</p> <p>Aim</p> <p>To investigate and present the reasons that cause the postponement of thoracic surgical operations.</p> <p>Methods</p> <p>We retrospectively included in the study all patients submitted to elective thoracic surgery in our department during the 4-year period 2007-2010 and noted all cases of postponement after official inclusion in the operating schedule.</p> <p>Results</p> <p>81 out of a total of 542 patients (14.9%) scheduled for elective thoracic operation had their procedure postponed. The reasons were mainly organisatory (in 42 cases, 51.85%), which in order of significance were: shortage in matching erythrocyte units, shortage in anaesthetic/nursing staff and unavailability in operating rooms. The rest of the cases (39, 48.1%) were postponed due to medical reasons, which in descending order of significance were: respiratory infections and exacerbations of COPD, cardiological problems, misregulation of antiplatelet/antithrombotic drugs and infections from other systems (gastrointestinal, urinary, etc.). Elderly male patients planned for major/oncologic surgery were most possible to have their operation postponed for medical reasons.</p> <p>Discussion-Conclusions</p> <p>Thoracic operations are postponed owed to organisatory as well as medical reasons, the latter mainly affecting elderly, morbid patients awaiting for major/oncologic surgery.</p

Species-level functional profiling of metagenomes and metatranscriptomes.

Functional profiles of microbial communities are typically generated using comprehensive metagenomic or metatranscriptomic sequence read searches, which are time-consuming, prone to spurious mapping, and often limited to community-level quantification. We developed HUMAnN2, a tiered search strategy that enables fast, accurate, and species-resolved functional profiling of host-associated and environmental communities. HUMAnN2 identifies a community's known species, aligns reads to their pangenomes, performs translated search on unclassified reads, and finally quantifies gene families and pathways. Relative to pure translated search, HUMAnN2 is faster and produces more accurate gene family profiles. We applied HUMAnN2 to study clinal variation in marine metabolism, ecological contribution patterns among human microbiome pathways, variation in species' genomic versus transcriptional contributions, and strain profiling. Further, we introduce 'contributional diversity' to explain patterns of ecological assembly across different microbial community types

Cost-effectiveness analysis of 3-D computerized tomography colonography versus optical colonoscopy for imaging symptomatic gastroenterology patients.

BACKGROUND: When symptomatic gastroenterology patients have an indication for colonic imaging, clinicians have a choice between optical colonoscopy (OC) and computerized tomography colonography with three-dimensional reconstruction (3-D CTC). 3-D CTC provides a minimally invasive and rapid evaluation of the entire colon, and it can be an efficient modality for diagnosing symptoms. It allows for a more targeted use of OC, which is associated with a higher risk of major adverse events and higher procedural costs. A case can be made for 3-D CTC as a primary test for colonic imaging followed if necessary by targeted therapeutic OC; however, the relative long-term costs and benefits of introducing 3-D CTC as a first-line investigation are unknown. AIM: The aim of this study was to assess the cost effectiveness of 3-D CTC versus OC for colonic imaging of symptomatic gastroenterology patients in the UK NHS. METHODS: We used a Markov model to follow a cohort of 100,000 symptomatic gastroenterology patients, aged 50 years or older, and estimate the expected lifetime outcomes, life years (LYs) and quality-adjusted life years (QALYs), and costs (£, 2010-2011) associated with 3-D CTC and OC. Sensitivity analyses were performed to assess the robustness of the base-case cost-effectiveness results to variation in input parameters and methodological assumptions. RESULTS: 3D-CTC provided a similar number of LYs (7.737 vs 7.739) and QALYs (7.013 vs 7.018) per individual compared with OC, and it was associated with substantially lower mean costs per patient (£467 vs £583), leading to a positive incremental net benefit. After accounting for the overall uncertainty, the probability of 3-D CTC being cost effective was around 60 %, at typical willingness-to-pay values of £20,000-£30,000 per QALY gained. CONCLUSION: 3-D CTC is a cost-saving and cost-effective option for colonic imaging of symptomatic gastroenterology patients compared with OC

Three-dimensional printing of porous load-bearing bioceramic scaffolds

This article reports on the use of the binder jetting three-dimensional printing process combined with sintering to process bioceramic materials to form micro- and macroporous three-dimensional structures. Three different glass-ceramic formulations, apatite–wollastonite and two silicate-based glasses, have been processed using this route to create porous structures which have Young’s modulus equivalent to cortical bone and average bending strengths in the range 24–36 MPa. It is demonstrated that a range of macroporous geometries can be created with accuracies of ±0.25 mm over length scales up to 40 mm. Hot-stage microscopy is a valuable tool in the definition of processing parameters for the sintering step of the process. Overall, it is concluded that binder jetting followed by sintering offers a versatile process for the manufacture of load-bearing bioceramic components for bone replacement applications

Pleosporales

One hundred and five generic types of Pleosporales are described and illustrated. A brief introduction and detailed history with short notes on morphology, molecular phylogeny as well as a general conclusion of each genus are provided. For those genera where the type or a representative specimen is unavailable, a brief note is given. Altogether 174 genera of Pleosporales are treated. Phaeotrichaceae as well as Kriegeriella, Zeuctomorpha and Muroia are excluded from Pleosporales. Based on the multigene phylogenetic analysis, the suborder Massarineae is emended to accommodate five families, viz. Lentitheciaceae, Massarinaceae, Montagnulaceae, Morosphaeriaceae and Trematosphaeriaceae