A Generalized Estimating Equations Approach to Model Heterogeneity and Time Dependence in Capture-Recapture Studies

Individual heterogeneity in capture probabilities and time dependence are fundamentally important for estimating the closed animal population parameters in capture-recapture studies. A generalized estimating equations (GEE) approach accounts for linear correlation among capture-recapture occasions, and individual heterogeneity in capture probabilities in a closed population capture-recapture individual heterogeneity and time variation model. The estimated capture probabilities are used to estimate animal population parameters. Two real data sets are used for illustrative purposes. A simulation study is carried out to assess the performance of the GEE estimator. A Quasi-Likelihood Information Criterion (QIC) is applied for the selection of the best fitting model. This approach performs well when the estimated population parameters depend on the individual heterogeneity and the nature of linear correlation among capture-recapture occasions

U.S. Collegiate Athletics: International Student Athletes Recruiting Process

The pressure to win has grown as a result of the billions of dollars invested in collegiate athletics and the increasing national media attention, and coaches and administrators are searching for an athletic edge (Wieberg, 2008). There are a limited number of American athletes that have the skills to impact the collegiate level. Competition to attract the top domestic players is high, so coaches turn to larger, international recruiting arenas with less competition (Riley, 1997). The National Collegiate Athletic Association (NCAA) regulates collegiate Sports in the United States, which is the only place in the world that provides the opportunity to participate in elite athletic competition while attaining a college degree. According to statistics from the NCAA, over 17,653 International Student Athletes (ISAs) participated in Divisions I, II and III during 2009-2010. This represents 10.24% of the total number of student-athletes participating in Division I, II, and III during 2009-2010. The ISAs’ participation has been constantly increasing through the years. The present study will examine the recruiting process of ISAs by exploring the following three questions:• Do coaches mainly use their personal Network to recruit ISAs?• Does the Network have an influence on the recruitment success rate?• Where do coaches go to recruit internationally? In this study, I used the qualitative research technique of in-depth interviews with 12 coaches and 10 ISAs of selected Division I and II NCAA member institutions in the state of South Carolina. I found common trends in the ISA recruiting process, grouped by level of competition. Based on the results I created a structure that describes the recruiting process of ISAs from the perspective of the Coaches and the ISAs. Results indicated that there are at least 8 methods used by coaches to identify elite ISAs; however, the coach’s personal-Network is the main one. Previously known as the “talent pipeline”, personal connections have evolved and expanded to become a Network. Depending on the level of competition there is a distinction in the use of the Network. Major Division I programs have better recruiting resources and prefer to do personalrecruitment of ISAs by attending International Tournaments. These coaches use the Network as an evaluating tool. On the contrary, Division I-AA and AAA and Division II coaches rely heavily on their network during the ISA recruiting process. The other methods for ISA recruiting are: direct contact through email, agencies, academies, showcases, U.S. college transfers and U.S. high schools. Additionally, the experience of the coach also had an influence on how the Network was used. Older coaches tend to rely greatly on their well-established Network as opposed to younger coaches who used academies, agencies, and showcases as alternative ways to identify ISAs while they build their network. Next, the recruiting success rate, usually a 5 to 1 ratio, is the same for international and domestic athletes according to the information provided by coaches during the interviews. The only exception to this ratio is when the ISA has been recommended by the coach’s personal network; then the probability of that ISA committing to the institution is close to a 1 to 1 ratio. Finally, coaches search for athletes everywhere. The network usually brings together athletes from the same country or same background; nonetheless Networks extend beyond one country’s limits and can easily cover zones of the world. Currently, the majority of ISAs in South Carolina originate from 6 countries including but not limited to Canada, Germany, England, Brazil, France and Australia. New trends were found in regards to the large increase in ISAs’ participation in Division II institutions in South Carolina. Further research should be conducted to determine if the new trend presents itself nationwide. It will also be interesting to study the athletic and economic impact that ISAs have in NCAA Collegiate Athletics. Furthermore, it would be important to examine the effectiveness of the Network in creating successful athletic programs and compare it with the effectiveness of the recruiting agencies

Rate coefficient for the reaction of Cl atoms with cis-3-hexene at 296 ± 2 K

The rate coefficient of the cis-3-hexene + Cl atoms reaction at 296 ± 2 K and 750 ± 10 Torr was determined using the relative rate technique. The reaction was investigated using an 80 L Teflon reaction bag and a gas chromatograph coupled with flame-ionization detection. Chlorine atoms were produced by the photolysis of trichloroacetyl chloride. No previous experimental data was available in the literature, to the best of our knowledge. The mean second-order rate coefficient value found was (4.13 ± 0.51) × 10-10 cm3 molecule-1 s-1. The experimental value agrees with the rate coefficient estimated by structure-reactivity analysis, 4.27 × 10-10 cm3 molecule-1 s-1. Moreover, both addition and hydrogen abstraction channels contribute to the global kinetics, with branching ratios 70:30. Effective lifetime with respect to Cl atoms is predicted as 67.2 hours; however, the cis-3-hexene + Cl channel is suggested to be non-negligible at atmospheric conditions. Other atmospheric implications are discussed.Fil: Barbosa, Thaís S.. Universidade Federal Rural do Rio de Janeiro; BrasilFil: Barrera, Javier Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Físico-química de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Investigaciones en Físico-química de Córdoba; ArgentinaFil: Jara Toro, Rafael Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Físico-química de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Investigaciones en Físico-química de Córdoba; ArgentinaFil: Bauerfeldt, Glauco F.. Universidade Federal Rural do Rio de Janeiro; BrasilFil: Arbilla, Graciela. Universidade Federal do Rio de Janeiro; BrasilFil: Lane, Silvia Irene. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Físico-química de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Investigaciones en Físico-química de Córdoba; Argentin

Costos reales de tratamientos intensivos por paciente y día cama

Alvear, S (Alvear, Sandra); Rodriguez, P (Rodriguez, Patricia).Univ Talca, Fac Ciencias Empresariales, Talca, ChileReal daily costs of patients admitted to public intensive care units Background: Patient care costs in intensive care units are high and should be considered in medical decision making. Aim: To calculate the real disease related costs for patients admitted to intensive care units of public hospitals. Material and Methods: Using an activity associated costs analysis, the expenses of 716 patients with a mean age of 56 years, mean APACHE score of 20 (56% males), admitted to intensive care units of two regional public hospitals, were calculated. Patients were classified according to their underlying disease. Results: The costs per day of hospital stay, in Chilean pesos, were $426,265 for sepsis,$ 423,300 for cardiovascular diseases, $418,329 for kidney diseases,$ 404,873 for trauma, $398,913 for respiratory diseases,$ 379,455 for digestive diseases and $ 371,801 for neurologic disease. Human resources and medications determined up to 85 and 12% of costs, respectively. Patients with sepsis and trauma use 32 and 19% of intensive care unit resources, respectively. Twenty seven percent of resources are invested in patients that eventually died. Conclusions: A real cost benefit analysis should be performed to optimize resource allocation in intensive care units. (Rev Med Chile 2013; 141: 202-208)

Nonequilibrium dynamics of a stochastic model of anomalous heat transport

We study the dynamics of covariances in a chain of harmonic oscillators with conservative noise in contact with two stochastic Langevin heat baths. The noise amounts to random collisions between nearest-neighbour oscillators that exchange their momenta. In a recent paper, [S Lepri et al. J. Phys. A: Math. Theor. 42 (2009) 025001], we have studied the stationary state of this system with fixed boundary conditions, finding analytical exact expressions for the temperature profile and the heat current in the thermodynamic (continuum) limit. In this paper we extend the analysis to the evolution of the covariance matrix and to generic boundary conditions. Our main purpose is to construct a hydrodynamic description of the relaxation to the stationary state, starting from the exact equations governing the evolution of the correlation matrix. We identify and adiabatically eliminate the fast variables, arriving at a continuity equation for the temperature profile T(y,t), complemented by an ordinary equation that accounts for the evolution in the bulk. Altogether, we find that the evolution of T(y,t) is the result of fractional diffusion.Comment: Submitted to Journal of Physics A, Mathematical and Theoretica

Stirring Unmagnetized Plasma

A new concept for spinning unmagnetized plasma is demonstrated experimentally. Plasma is confined by an axisymmetric multi-cusp magnetic field and biased cathodes are used to drive currents and impart a torque in the magnetized edge. Measurements show that flow viscously couples momentum from the magnetized edge (where the plasma viscosity is small) into the unmagnetized core (where the viscosity is large) and that the core rotates as a solid body. To be effective, collisional viscosity must overcome the ion-neutral drag due to charge exchange collisions

Extending the Internet of Things to the future Internet through IPv6 Support

Emerging Internet of Things (IoT)/Machine-to-Machine (M2M) systems require a transparent access to information and services through a seamless integration into the Future Internet. This integration exploits infrastructure and services found on the Internet by the IoT. On the one hand, the so-called Web of Things aims for direct Web connectivity by pushing its technology down to devices and smart things. On the other hand, the current and Future Internet offer stable, scalable, extensive, and tested protocols for node and service discovery, mobility, security, and auto-configuration, which are also required for the IoT. In order to integrate the IoT into the Internet, this work adapts, extends, and bridges using IPv6 the existing IoT building blocks (such as solutions from IEEE 802.15.4, BT-LE, RFID) while maintaining backwards compatibility with legacy networked embedded systems from building and industrial automation. Specifically, this work presents an extended Internet stack with a set of adaptation layers from non-IP towards the IPv6-based network layer in order to enable homogeneous access for applications and services

Crossover to the KPZ equation

We characterize the crossover regime to the KPZ equation for a class of one-dimensional weakly asymmetric exclusion processes. The crossover depends on the strength asymmetry $an^{2-\gamma}$ ($a,\gamma>0$) and it occurs at $\gamma=1/2$. We show that the density field is a solution of an Ornstein-Uhlenbeck equation if $\gamma\in(1/2,1]$, while for $\gamma=1/2$ it is an energy solution of the KPZ equation. The corresponding crossover for the current of particles is readily obtained.Comment: Published by Annales Henri Poincare Volume 13, Number 4 (2012), 813-82