Anomalous lifetime distributions and topological traps in ordering dynamics

We address the role of community structure of an interaction network in ordering dynamics, as well as associated forms of metastability. We consider the voter and AB model dynamics in a network model which mimics social interactions. The AB model includes an intermediate state between the two excluding options of the voter model. For the voter model we find dynamical metastable disordered states with a characteristic mean lifetime. However, for the AB dynamics we find a power law distribution of the lifetime of metastable states, so that the mean lifetime is not representative of the dynamics. These trapped metastable states, which can order at all time scales, originate in the mesoscopic network structure.Comment: 7 pages; 6 figure

Adaptive correlations between seed size and germination time

We present a model for the coevolution of seed size and germination time within a season when both affect the ability of the seedlings to compete for space. We show that even in the absence of a morphological or physiological constraint between the two traits, a correlation between seed size and germination time is nevertheless likely to evolve. This raises the more general question to what extent a correlation between any two traits should be considered as an a priori constraint or as an evolved means (or instrument) to actually implement a beneficial combination of traits. We derive sufficient conditions for the existence of a positive or a negative correlation. We develop a toy model for seed and seedling survival and seedling growth and use this to illustrate in practice how to determine correlations between seed size and germination time.Peer reviewe

Standoff UV-C imaging of alpha particle emitters

Alpha particles are proven to be very useful in many areas of medicine, technology and science. Yet, they represent the biggest risk to soft biological tissues compared to all nuclear decay products when ingested or inhaled, implying thus stringent radiation protection measures in the management and monitoring of samples that emit them. In this paper we present a standoff optical imaging approach that enables sensing of a radiological threat items at facilities where alpha-emitting material is manufactured, handled, used and stored, at safe distances without putting personnel at risk or contaminating equipment. The optical imaging of alpha-emitting samples is based on the radiation induced air luminescence (radioluminescence) in the UV-C (solar-blind) spectral region which enables detection of alpha particles even under bright light conditions. We show that by adding trace amounts of nitric oxide into the nitrogen atmosphere surrounding the sample, alpha sources with specific activities as low as 1.5 Bq/cm(2) can be remotely imaged. This work provides a proof-of-concept implementation of a novel imaging approach that not only enhances capabilities of a state to take actions which effectively mitigate consequences of an radiological emergency for the society, health, environment and economy, but also benefits nuclear industry in decommissioning efforts.Peer reviewe

Dronedarone in high-risk permanent atrial fibrillation

BACKGROUND: Dronedarone restores sinus rhythm and reduces hospitalization or death in intermittent atrial fibrillation. It also lowers heart rate and blood pressure and has antiadrenergic and potential ventricular antiarrhythmic effects. We hypothesized that dronedarone would reduce major vascular events in high-risk permanent atrial fibrillation. METHODS: We assigned patients who were at least 65 years of age with at least a 6-month history of permanent atrial fibrillation and risk factors for major vascular events to receive dronedarone or placebo. The first coprimary outcome was stroke, myocardial infarction, systemic embolism, or death from cardiovascular causes. The second coprimary outcome was unplanned hospitalization for a cardiovascular cause or death. RESULTS: After the enrollment of 3236 patients, the study was stopped for safety reasons. The first coprimary outcome occurred in 43 patients receiving dronedarone and 19 receiving placebo (hazard ratio, 2.29; 95% confidence interval [CI], 1.34 to 3.94; P = 0.002). There were 21 deaths from cardiovascular causes in the dronedarone group and 10 in the placebo group (hazard ratio, 2.11; 95% CI, 1.00 to 4.49; P = 0.046), including death from arrhythmia in 13 patients and 4 patients, respectively (hazard ratio, 3.26; 95% CI, 1.06 to 10.00; P = 0.03). Stroke occurred in 23 patients in the dronedarone group and 10 in the placebo group (hazard ratio, 2.32; 95% CI, 1.11 to 4.88; P = 0.02). Hospitalization for heart failure occurred in 43 patients in the dronedarone group and 24 in the placebo group (hazard ratio, 1.81; 95% CI, 1.10 to 2.99; P = 0.02). CONCLUSIONS: Dronedarone increased rates of heart failure, stroke, and death from cardiovascular causes in patients with permanent atrial fibrillation who were at risk for major vascular events. Our data show that this drug should not be used in such patients. (Funded by Sanofi-Aventis; PALLAS ClinicalTrials.gov number, NCT01151137.) Copyright © 2011 Massachusetts Medical Society. All rights reserved.published_or_final_versio

Hajalukujen tunnistaminen ja poistaminen RFID-porteilla

A modern UHF RFID system can reach a read range of over ten meters. Long read range and difficulties to create uniform interrogation zone lead to stray reads. Interrogation zone can be adjusted by controlling the transmit power of RFID reader, selecting antennas and RFID tags carefully for the purpose, and with different signal quality validation methods. It is common that industry processes prevent using optimal RFID tag size and location for best read reliability. In these situations reader transmit power is increased to gain better read reliability. This extends the interrogation zone over the designed and leads to stray reads. At UHF band the interrogation zone is not sharp edged. This is due to orientation differences between tags, tag to tag differences, multipathing and interference caused by multipathing. In this thesis, different methods to identify RFID-tags moving along specified routes in the far field on the specific interrogation zone and discard other read events as stray events, are studied. Algorithm to detect lay around tags is proposed.Modernin UHF RFID-järjestelmän lukuetäisyys on parhaimmillaan yli kymmenen metriä. Suuri lukuetäisyys ja hankaluudet lukualueen tarkassa rajaamisessa johtavat hajalukuihin. Lukualuetta voidaan säätää RFID-lukijan lähetystehoa muuttamalla, antenni- ja RFID-tunnistevalinnoilla, sekä erilaisilla signaalin laatuun liittyvillä menetelmillä. Teollisuuden prosessit eivät aina mahdollista tunnisteen sijoittamista lukuvarmuuden kannalta parhaaseen paikkaan. Tällaisissa tapauksissa joudutaan usein kasvattamaan RFID-lukijan lähetystehoa lukuvarmuuden parantamiseksi. Tämä taas kasvattaa lukualuetta suunniteltua suuremmaksi, mikä johtaa hajalukuihin. UHF taajuuksilla lukualue ei ole tarkkareunainen, johtuen RFID-tunnisteiden asentoeroista, tunnisteiden yksilökohtaisista eroista sekä monikanavakuulumisesta ja siihen liittyvästä interferenssistä. Tässä tutkimuksessa on etsitty ja kokeiltu menetelmiä, joilla voidaan tunnistaa määritellyllä lukualueella lukijan kaukokentässä haluttuja reittejä liikkuvat RFID-tunnisteet ja hylätä muut lukutapahtumat hajalukuina. Tutkimuksessa esitetään uusi algoritmi hajalukujen tunnistamiseksi

Mesoscopic effects in an agent-based bargaining model in regular lattices

The effect of spatial structure has been proved very relevant in repeated games. In this work we propose an agent based model where a fixed finite population of tagged agents play iteratively the Nash demand game in a regular lattice. The model extends the multiagent bargaining model by Axtell, Epstein and Young [1] modifying the assumption of global interaction. Each agent is endowed with a memory and plays the best reply against the opponent’s most frequent demand. We focus our analysis on the transient dynamics of the system, studying by computer simulation the set of states in which the system spends a considerable fraction of the time. The results show that all the possible persistent regimes in the global interaction model can also be observed in this spatial version. We also find that the mesoscopic properties of the interaction networks that the spatial distribution induces in the model have a significant impact on the diffusion of strategies, and can lead to new persistent regimes different from those found in previous research. In particular, community structure in the intratype interaction networks may cause that communities reach different persistent regimes as a consequence of the hindering diffusion effect of fluctuating agents at their borders.Spanish Ministry of Science and Innovation, references TIN2008-06464-C03-02 and CSD2010-00034 (CONSOLIDER-INGENIO 2010), and by the Junta de Castilla y Leon, references VA006A009, BU034A08 and GREX251-200

Performance of Surgical Stress Index during Sevoflurane-Fentanyl and Isoflurane-Fentanyl Anesthesia

The performance of recently introduced Surgical Stress Index (SSI), based on heart rate and photoplethysmography, was estimated during sevoflurane-fentanyl and isoflurane-fentanyl anesthesia during surgical procedures. Forty ASA I–III patients were enrolled. Anesthesia was induced with fentanyl 2 μg kg−1 and thiopentone 3–5 mg kg−1. Tracheal intubation was performed 5 minutes after fentanyl bolus. Patients were randomly allocated to receive sevoflurane (n = 20) or isoflurane (n = 20) in 30% oxygen/air. State entropy was kept at 40–60, target being 50. During surgery, fentanyl boluses 1.5 μg kg−1 were given at 30–40-minute intervals. SSI increased significantly after intubation. During surgery, the decrease of SSI after fentanyl boluses was similar in sevoflurane and isoflurane groups but SSI values were higher in sevoflurane than in isoflurane group. Tracheal intubation, skin incision, and surgical stimuli increased SSI from baseline, indicating that nociceptive stimuli increase SSI. Fentanyl boluses during surgery decreased SSI, indicating that increasing analgesia decreases SSI

Mediation and the Best Interests of the Child from the Child Law Perspective

What is the best interests of the child in family mediation and is mediation in the best interests of the child? In this article, I use child law and the United Nations Convention on the Rights of the Child combined with mediation theory to discuss these questions. Both mediation and the best interests of the child are open for multiple interpretations. Using facilitative and evaluative mediation theory and the legal concept ‘the best interests of the child’, I explore and compare the understandings of these concepts as they apply to family mediation. This includes a discussion of the advantages and disadvantages of facilitative as well as evaluative mediation orientations in terms of protecting the best interests of the child. Finnish court-connected family mediation is a combination of both mediation orientations, and the mediator is obliged to secure the best interests of the child. From a theoretical point of view, this seems to be a challenging combination.Peer reviewe

Allocating Logging Rights in Peruvian Amazonia-Does It Matter to Be Local?

Conclusions/Significance: The allocation process left a considerable number of forest areas under the management of small and local actors, and if Peru is to reach its goal of zero deforestation rate by safeguarding 75 per cent of its forests by 2020, the small and the local actors need to be integrated to the forest regime as important constituents of its legitimacy