Miracle-dz/UniFAR-FTUs huggingface dataset:
REENTRANT WAVES INDUCED BY LOCAL BISTABILITIES IN A CARDIAC MODEL

Rate-dependent bistability and hysteresis have recently been observed to be highly prevalent in periodically stimulated bullfrog ventricular muscle. Similar bistabilities have been found in in vivo sheep atria at interstimulus intervals for which spatiotemporally complex behaviors, possibly atrial flutter and fibrillation, are observed. Might bistability play a role in the onset of spatiotemporal disorganization in the whole heart? We investigate the role of local bistability in a coupled map/cellular automaton model of cardiac dynamics. This two-dimensional model is based on a simple mapping which gives good qualitative agreement with many of the local features of cardiac dynamics. Under some conditions, local regions of bistability are found to result in phase singularities and rotors in the spatially extended model presented here. Introduction and Background Different patterns of dynamical response can be elicited under different conditions in cardiac tissue. For example, when stimuli are delivered at a slow rate, one action potential response is elicited for every stimulus (denoted as a 1:1 state). As the stimulus rate (basic cycle length, or BCL) is increased, the action potential duration (APD) begins to oscillate, entering a state called “alternans”, in which every stimulus elicits a response but the responses are of alternating duration (2:2 state) [1,2,3]. As the stimulus rate is increased further, the tissue becomes unable to recover fast enough to respond to every applied stimulus, resulting in a pattern of “skipped beats”, where every other stimulus elicits a response (2:1 pattern). Under other conditions (e.g., different range of applied current amplitude), more complicated behaviors arise [4,5,6]. As pointed out by Guevara et al. [2], rate-dependent bistability and hysteresis between 1:1 (or 2:2) and 2:1 states can occur in simple models of cardiac dynamics as the interstimulus interval (here called BCL, or basic cycle length) is swept up and down. Bistability between the 1:1 branch and the 2:1 branch of APD response was first observed experimentally by Mines in 1913 in a bullfrog cardiac preparation [7], and later by Guevara et al. [4] in an aggregate of spontaneously beating chick embryonic ventricular myocytes. Recently it has been shown that bistability is a highly prevalent local behavior in bullfrog ventricular myocardium, occurring in 74% of preparations studied [8]. Bistability was subsequently observed in in vivo sheep atrium for BCL values over which arrhythmias and spatiotemporal disorganization (possibly flutter or fibrillation) also occurred [9]. Can local bistabilities play a role in the onset of spatial disorganization in excitable media? We investigate this question using a simple cardiac model.
Establishment of a Comprehensive Epilepsy Center in Pakistan: Initial Experiences, Results, and Reflections

Background. Developing countries, home to 80% of epilepsy patients, do not have comprehensive epilepsy surgery programs. Considering these needs we set up first epilepsy surgery center in Pakistan. Methods. Seventeen teleconferences focused on setting up an epilepsy center at the Aga Khan University (AKU), Karachi, Pakistan were arranged with experts from the University of Alberta Hospital, Alberta, Canada and the University of West Virginia, USA over a two-year period. Subsequently, the experts visited the proposed center to provide hands on training. During this period several interactive teaching sessions, a nationwide workshop, and various public awareness events were organized. Results. Sixteen patients underwent surgery, functional hemispherectomy (HS) was done in six, anterior temporal lobectomy (ATL) in six, and neuronavigation-guided selective amygdalohippocampectomy (SAH) using keyhole technique in four patients. Minimal morbidity was observed in ATL and, SAH groups. All patients in SAH group (100%) had Grade 1 control, while only 5 patients (83%) in ATL group, and 4 patients (66%) in HS group had Grade 1 control according to Engel's classification, in average followups of 12 months, 24 months and 48 months for SAH, ATL, and HS, respectively. Conclusion. As we share our experience we hope to set a practical example for economically constrained countries that successful epilepsy surgery centers can be managed with limited resources.
Environmental Agreements in a Two-Level Dynamic Framework

This paper addresses the issue of conflicts between countries who share a renewable natural resource using a two-level framework. Contrary to the usual modeling of countries as representative agents who sign an international treaty to protect the resource that they share, this research considers the existence of some interaction between different sort of consumers and firms within each country. It discusses the influence of both domestic characteristics (consumers´ preferences and firms´costs) and the presence of some national environmental policy on the resulting regional agreement. The international level is modeled as a dynamic game in which each government decides its domestic regulation. Agreements are viewed as the result of some sort of bargaining among countries. An important insight of this paper is the incorporation of a numerical simulation (for a linearquadratic example) to depict the dynamics of the model. In particular, its main result is an estimation of the path of emissions with the optimum treaty and without any agreement (the Markov Perfect equilibrium of the game).
A Distributed Trust-based Recommendation System on Social Networks

In everyday life, we seek suggestions from people we know for deciding the best place to buy a particular good or service. In this work, we put forth a framework of an automated distributed recommendation system on a social network that exploits the widely studied concept of trust, to get personalized responses. The main contribution of our model is to combine two forms in which trust is perceived, the friendship trust and domain-expertise based trail levels, to efficiently propagate a query on a social network. We empirically validate the role of trust in online social networks by crawling the online social networking site Orkut and evaluate our recommendation system against one in which trust has not been used. We also analyze the results by varying different parameters of our model. Our framework is designed to work in a distributed environment and can thus be useful with upcoming technologies such as Mobile Ad Hoc networks, P2P networks and Semantic Web.
Election polls, the news media, and democracy

Part 1 Introduction: election polling and democracy, Paul J. Lavrakas, Michael W. Traugott. Part 2 The use of election polls in 1996: the continuing evolution in the use of public opinion polls by The New York Times - the 1996 presidential election experience a review of the 1996 Voter News Service exit polls using a total survey error perspective, Daniel M. Merkle, Murray Edelman deliberative polling in the 1996 elections, Vincent Price the hidden value in combining election polling and public journalism, Philip Meyer, Deborah Potter mixing literacy journalism and precision journalism in coverage of the 1996 presidential election, Gerald M. Kosicki and Paul J. Lavrakas. Part 3 The methods of election polls: how to model the probably electorate in preelection polls, Robert P. Daves improving election forecasting - allocation of undecideds, identifying likely voters, and response order effects, Penny S. Visser et al. Part 4 Election poll effects: public attention to election polls - the 1996 experience, Michael W. Traugott, Mee-Eun Kang the use of casual attribution in election poll news stories, Sandra L. Bauman, Paul J. Lavrakas did public opinion support the contract with America? Michael Traugott, Elizabeth C. Powers politics, polls, and poltergeists - a review of 1996 election surveying, Leo Bogart. Part 5 Conclusion: election polling and democracy in the 21st century, Paul J. Lavrakas, Michael W. Traugott.
Reported Reservation Wages and Search Theory

have used responses to questions such as " What is the lowest wage you would be willing to accept? " to describe the search behaviour of the unemployed. Do reported reservation wages correspond to the concept of reservation wages that economists have? 1 For example, Dawes (1993), in a study of long-term British unemployed, stated that " the concept of the reservation wage is misleading " (p.31–2). He concluded that, for the long-term unemployed, responses to questions like those above indicate subsistence requirements rather than self perceived labour market value. He also concluded that reservation wages appear to have no predictive value in terms of indicating the likelihood of accepting an offer or the wages actually received. His sample consisted of unemployed claimants who had been claiming benefits for at least six months, i.e. a selected subgroup of the population, and it is not clear whether this conclusion is true for the whole population. Analyses of reservation wages and comparisons with benefits received (e.g. Shaw et al. (1996)), wage expectations (e.g. Dawes (1993), or the threshold level of benefit eligibility (e.g. Marsh and McKay (1993)) regularly focus on subgroups, such as lone parents, the long-term unemployed, or benefit claimants. There has been no study using British data that attempts to compare reported reservation wages with reservation wages which are derived from a job search model for the whole working-age population. To my knowledge, Schmidt's and Winkelmann's (1993) study is the only one that relates reported reservation wages to the reservation wages that are implied by search theory, the distribution of accepted wages and completed unemployment durations. They used data for 1977 about German job seekers and found that reported reservation wages were " largely compatible " with those derived from the search model. By this they meant that reported reservation wages and the reservation wages calculated from their model were on average the same. A regression of calculated reservation wages on reported reservation wages yielded an intercept of zero and a slope of one. I use reservation wage and unemployment duration data from the British Household Panel Survey (BHPS) covering the years 1991–7. At interest rates below 5% per annum the estimated relationship between men's reported and calculated reservation wages is compatible with the simple search model, i.e. 1 Kasper (1967) provides one of the first attempts at analysing this question.
Ultra Linear Low-Loss Varactor Diode Configurations for Adaptive RF Systems

Two linear low-loss varactor configurations for tunable RF applications are compared. The wide tone-spacing varactor stack provides the best linearity for signals with relative large tone spacing like receiver jammer situations. The narrow tone-spacing varactor stack offers the highest linearity for in-band-modulated signals, and is better suited to adaptive transmitters. Both structures make use of a varactor with an exponential C(VR) relation, and so the different requirements of transmit and receive chains can be addressed in one technology. Both configurations have been realized in a silicon-on-glass technology. The measured Q at 1.95 GHz is from ~ 40 to 200 over a capacitance tuning range of 3.5 with the maximum control voltage of 12 V. The measured OIP3 of both structures are roughly 60 dBm.
Reducing Scalability Collapse via Requester-Based Locking on Multicore Systems

In response to the increasing ubiquity of multicore processors, there has been widespread development of multithreaded applications that strive to realize their full potential. Unfortunately, lock contention within operating systems can limit the scalability of multicore systems so severely that an increase in the number of cores can actually lead to reduced performance (i.e. scalability collapse). Existing lock implementations have disadvantages in scalability, resource utilization and energy efficiency. In this work, we observe that the number of tasks requesting a lock has a significant correlation with the occurrence of scalability collapse. Based on this observation, we propose a novel lock implementation that allows tasks blocked on a lock to either spin or maintain a power-saving state according to the number of lock requesters. We call our lock implementation protocol a requester-based lock and implement it in the Linux kernel to replace its default spin lock. Based on the results of an analysis, we find that the best policy for a task waiting for a lock to become free is to enter the power saving state immediately after noticing that the lock cannot be acquired. Our lock-requester based lock scheme is evaluated using micro- and macro-benchmarks on AMD 32-core and Intel 40-core systems. Experimental results indicate our lock scheme removes scalability collapse completely for most applications. Furthermore, our method shows better scalability and energy efficiency than mutex locks and adaptive locks.
Zur Rolle der Ökonometrie in der wissenschaftlichen Politikberatung

Abstract Because economic theory alone does in many situations not provide unambiguous policy advice, most of the time empirical analyses are needed in addition. Thus, today econometric analyses are often parts of reports for political institutions or courts. However, it is not unusual that reports with contradicting evidence are presented by different groups or parties. Using the relation between government size and economic growth as an example, it is shown how such contradicting results are possible even if all scientists involved behave sincerely and adhere to the rules of scientific research. Our second example, studies investigating whether the death penalty serves as a deterrent to homicide, shows that the results of empirical analyses might to a large extent depend on a priori convictions of the scientists. Thus, the process of scientific policy advice has to be organised in a way so that - similar to the genuinely scientific discourse - open discussion and criticisms of methods and results are possible. In order to disclose possible conflicts of interests, this demand transparency of the whole process and, in particular for empirical analyses, that data and programmes are made available for re-estimations.
BRAC's contribution to the gross domestic product of Bangladesh

This paper estimates the contribution of BRAC programmes to the gross domestic product (GDP) of Bangladesh. BRAC's contribution to GDP of Bangladesh has been divided into four components. These are 1) Value added in BRAC as an organization in a given year, 2) Incremental value added in linked sectors due to input supply to BRAC in a given year, 3) Incremental value added in linked sectors attributed to loans disbursed by BRAC in a given year, and 4) Incremental value added in linked sectors attributed to nonfinancial development inputs (skill training, non-formal primary education, and health services) in a given year. BRAC contributed Tk. 8,215.3 million, Tk. 10,479.1 million, Tk. 13,558 million and Tk. 17,770.3 million to GDP ofBangladesh in 1995, 1996, 1997 and 1998 respectively. In 1995 BRAC's share to GDP was 0.7%, which increased to 1.15% in 1998. This shows that output of BRAC increased faster than GDP of Bangladesh. During the period output of BRAC increased, on average, at 29.1% annually. But estimating the contribution of education intervention was not possible due to lack of information on the sectoral wage differential of the BRAC graduates and those without any education. Therefore, the total output of BRAC is not fully captured in the present study.
Maternal dietary patterns in pregnancy and the association with small-for-gestational-age infants

Maternal nutritional status before and during pregnancy is important for the growth and development of the fetus. The effects of pre-pregnancy nutrition (estimated by maternal size) are well documented. There is little information in today's Western society on the effect of maternal nutrition during pregnancy on the fetus. The aim of the study was to describe dietary patterns of a cohort of mothers during pregnancy (using principal components analysis with a varimax rotation) and assess the effect of these dietary patterns on the risk of delivering a small-for-gestational-age (SGA) baby. The study was a case–control study investigating factors related to SGA. The population was 1714 subjects in Auckland, New Zealand, born between October 1995 and November 1997, about half of whom were born SGA ( ≤ 10th percentile for sex and gestation). Maternal dietary information was collected using FFQ after delivery for the first and last months of pregnancy. Three dietary patterns (traditional, junk and fusion) were defined. Factors associated with these dietary patterns when examined in multivariable analyses included marital status, maternal weight, maternal age and ethnicity. In multivariable analysis, mothers who had higher ‘traditional’ diet scores in early pregnancy were less likely to deliver a SGA infant (OR = 0·86; 95 % CI 0·75, 0·99). Maternal diet, particularly in early pregnancy, is important for the development of the fetus. Socio-demographic factors tend to be significantly related to dietary patterns, suggesting that extra resources may be necessary for disadvantaged mothers to ensure good nutrition in pregnancy.
Formation of Millisecond Pulsars from Accretion-induced Collapse and Constraints on Pulsar Gamma-Ray Burst Models

We study accretion-induced collapse of magnetized white dwarfs as an origin of millisecond pulsars. We apply magnetized accretion disk models to the precollapse accreting magnetic white dwarfs and calculate the white dwarf spin evolution. If the pulsar magnetic field results solely from the flux-frozen fossil white dwarf field, a typical millisecond pulsar is born with a field strength ~1011-1012 G. The uncertainty in the field strength is mainly due to the uncertain physical parameters of the magnetized accretion disk models. A simple correlation between the pulsar spin Ω* and the magnetic field B*, (Ω*/104 s-1) ~ (B*/1011 G)-4/5, is derived for a typical accretion rate ~5 × 10-8 M☉ yr-1. This correlation remains valid for a wide precollapse physical conditions unless the white dwarf spin and the binary orbit are synchronized prior to accretion induced collapse. We critically examine the possibility of spin-orbit synchronization in close binary systems. Using idealized homogeneous ellipsoid models, we compute the electromagnetic and gravitational wave emission from the millisecond pulsars and find that electromagnetic dipole emission remains nearly constant while millisecond pulsars may spin up rather than spin down as a result of gravitational wave emission. We also derive the physical conditions under which electromagnetic emission from millisecond pulsars formed by accretion-induced collapse can be a source of cosmological gamma-ray bursts. We find that relativistic beaming of gamma-ray emission and precession of gamma-ray-emitting jets are required unless the dipole magnetic field strengths are greater than 1015 G; such strong dipole fields are in excess of those allowed from the accretion-induced collapse formation process except in spin-orbit synchronization. Strong dipole fields greater than 1015 G could in principle be produced in situ. If the millisecond pulsars spin up while emitting gravitational waves, the required values for the shortest bursts are greater than 1016 G, which pushes the limits of suggested neutron star dynamos.
Judgment and Decision Making Accounting Research: A Quest to Improve the Production, Certification, and Use of Accounting Information

This chapter reviews the judgment and decision making research (JDM) that involves the production, certification and use of accounting information. We first outline the domain of accounting information and the roles of professional accountants and other users of accounting information. We then provide a brief historical perspective on accounting JDM research. We describe the current impact of JDM accounting research on accounting research more generally in the period 1995-2002 via an analysis of JDM accounting publications in top accounting journals. We then turn to describing recent foci of JDM accounting research both quantitatively using the classifications in this Handbook and qualitatively by examining in some detail significant recent JDM accounting articles. We conclude with some observations about the future of JDM accounting research.
Steganography using Concept of Skin Tone Detection

Steganography is the art of hiding the existence of data in another transmission medium to achieve secret communication. Steganography method used in this paper is based on biometrics. And the biometric feature used to implement Steganography is skin tone region of images.In this paper, describes an implementation for skin detection which relies on the HSV(Hue, Saturation and Value) color space model. In the detected skin area we are able to hide the secret data. Due to skin color variation from zero to one; any change in skin color is not affecting original image and also human visual system.
Temporal dynamics of ocular aberrations: monocular vs binocular vision

The temporal dynamics of ocular aberrations are important for the evaluation of, e.g. the accuracy of aberration estimates, the correlation to visual performance, and the requirements for real‐time correction with adaptive optics. Traditionally, studies on the eye’s dynamic behavior have been performed monocularly, which might have affected the results. In this study we measured aberrations and their temporal dynamics both monocularly and binocularly in the relaxed and accommodated state for six healthy subjects. Temporal frequencies up to 100 Hz were measured with a fast‐acquisition Hartmann–Shack wavefront sensor having an open field‐of‐view configuration which allowed fixation to real targets. Wavefront aberrations were collected in temporal series of 5 s duration during binocular and monocular vision with fixation targets at 5 m and 25 cm distance. As expected, a larger temporal variability was found in the root‐mean‐square wavefront error when the eye accommodated, mainly for frequencies lower than 30 Hz. A statistically‐significant difference in temporal behavior between monocular and binocular viewing conditions was found. However, on average it was too small to be of practical importance, although some subjects showed a notably higher variability for the monocular case during near vision. We did find differences in pupil size with mono‐ and binocular vision but the pupil size temporal dynamics did not behave in the same way as the aberrations’ dynamics.
The planet in M4: implications for planet formation in globular clusters

We consider the formation and evolution of the planetary system PSR B1620‐26 in the globular cluster M4. We propose that as M4 is a very low-metallicity environment the standard model of planet formation around main-sequence stars through the accretion of gas on to metallic rocky cores should not be applied. Consequently the previously suggested methods for formation are unlikely. We propose that the planet formed through the interaction of a passing star with a circumbinary disc during the common-envelope phase of the evolution of the inner binary. This formation route is favoured by dense stellar systems such as globular clusters. Ke yw ords: planets and satellites: formation ‐ planetary systems: protoplanetary discs ‐ pulsars: individual: PSR B1620‐26.
Weak Relative Pseudo-complements of Closure Operators Weak Relative Pseudo-complements of Closure Operators

We deene the notion of weak relative pseudo-complement, and we show that, for an arbitrary lattice, the property of weak relative pseudo-complementation is strictly weaker than relative pseudo-complementation, but stronger than pseudo-complementation. Our main interest for this notion is in relation with the theory of closure operators. We prove that if a complete lattice L is completely inf-distributive with respect to chains, then every closure operator on L admits weak relative pseudo-complements with respect to continuous closure operators on L.