On the rotation of ONC stars in the Tsallis formalism context

The theoretical distribution function of the projected rotational velocity is derived in the context of the Tsallis formalism. The distribution is used to estimate the average for a stellar sample from the Orion Nebula Cloud (ONC), producing an excellent result when compared with observational data. In addition, the value of the parameter q obtained from the distribution of observed rotations reinforces the idea that there is a relation between this parameter and the age of the cluster.Comment: 6 pages, 2 figure

Agricultural productivity in the European Union convergence or divergence among members?

Sound increases in agricultural productivity and incomes have been from the very begining two of the main goals of the Common Agricultural Policy of the European Economic Community (now European Union - EU). The paper tries to evaluate, through the estimation of convergence coefficients, if the increments achieved have widened or closed the gap between EU member states. Results indicate that the richest countries either maintain their positive differences to the Union's average (Netherlands and Belgium) or even enlarge it (Denmark). France shows a quick convergence pattern, while countries where Mediterranean production exceeds 30 % of Total Agricultural Output either keep their negative gap (Italy), or even enlarge it (Greece) or slowly converge to the average (Spain). Portugal does converge but still has a long way to reach its European partners. For the remaining countries no significant convergence coefficients were found.

Strong evidences for a nonextensive behavior of the rotation period in Open Clusters

Time-dependent nonextensivity in a stellar astrophysical scenario combines nonextensive entropic indices $q_{K}$ derived from the modified Kawaler's parametrization, and $q$, obtained from rotational velocity distribution. These $q$'s are related through a heuristic single relation given by $q\approx q_{0}(1-\Delta t/q_{K})$, where $t$ is the cluster age. In a nonextensive scenario, these indices are quantities that measure the degree of nonextensivity present in the system. Recent studies reveal that the index $q$ is correlated to the formation rate of high-energy tails present in the distribution of rotation velocity. On the other hand, the index $q_{K}$ is determined by the stellar rotation-age relationship. This depends on the magnetic field configuration through the expression $q_{K}=1+4aN/3$, where $a$ and $N$ denote the saturation level of the star magnetic field and its topology, respectively. In the present study, we show that the connection $q-q_{K}$ is also consistent with 548 rotation period data for single main-sequence stars in 11 Open Clusters aged less than 1 Gyr. The value of $q_{K}\sim$ 2.5 from our unsaturated model shows that the mean magnetic field topology of these stars is slightly more complex than a purely radial field. Our results also suggest that stellar rotational braking behavior affects the degree of anti-correlation between $q$ and cluster age $t$. Finally, we suggest that stellar magnetic braking can be scaled by the entropic index $q$.Comment: 6 pages and 2 figures, accepted to EPL on October 17, 201

The Use of Violence in Illegal Markets: Evidence from Mahogany Trade in the Brazilian Amazon

Agents operating in illegal markets cannot resort to the justice system to guarantee property rights, to enforce contracts, or to seek protection from competitors' improper behaviors. In these contexts, violence is used to enforce previous agreements and to fight for market share. This relationship plays a major role in the debate on the pernicious effects of the illegality of drug trade. This paper explores a singular episode of transition of a market from legal to illegal to provide a first piece of evidence on the causal effect of illegality on systemic violence. Brazil has historically been the main world producer of big leaf mahogany (a tropical wood). Starting in the 1990s, policies restricting extraction and trade of mahogany, culminating with prohibition, were implemented. First, we present evidence that large scale mahogany trade persisted after prohibition, through misclassification of mahogany exports as "other tropical timber species." Second, we document relative increases in violence after prohibition in areas with: (i) higher share of mahogany exports before prohibition; (ii) higher suspected illegal mahogany activity after prohibition; and (iii) natural occurrence of mahogany. We believe this is one of the first documented experiences of increase in violence following the transition of a market from legal to illegal.illegal markets, violence, homicide, mahogany, Brazil

The use of violence ini llegal markets: evidence from mahogany trade in the Brazilian Amazon

Agents operating in illegal markets cannot resort to the justice system to guarantee property rights, to enforce contracts, or to seek protection from competitors’ improper behaviors. In these contexts, violence is used to enforce previous agreements and to fight for market share. This relationship plays a major role in the debate on the pernicious effects of the illegality of drug trade. This paper explores a singular episode of transition of a market from legal to illegal to provide a first piece of evidence on the causal effect of illegality on systemic violence. Brazil has historically been the main world producer of big leaf mahogany (a tropical wood). Starting in the 1990s, policies restricting extraction and trade of mahogany, culminating with prohibition, were implemented. First, we present evidence that large scale mahogany trade persisted after prohibition, through misclassification of mahogany exports as “other tropical timber species.” Second, we document relative increases in violence after prohibition in areas with: (i) higher share of mahogany exports before prohibition; (ii) higher suspected illegal mahogany activity after prohibition; and (iii) natural occurrence of mahogany. We believe this is one of the first documented experiences of increase in violence following the transition of a market from legal to illegal.illegal markets, violence, homicide, mahogany, Brazil Jel Codes: K42, O13, O17, Q58

An extended formalism for preferential attachment in heterogeneous complex networks

In this paper we present a framework for the extension of the preferential attachment (PA) model to heterogeneous complex networks. We define a class of heterogeneous PA models, where node properties are described by fixed states in an arbitrary metric space, and introduce an affinity function that biases the attachment probabilities of links. We perform an analytical study of the stationary degree distributions in heterogeneous PA networks. We show that their degree densities exhibit a richer scaling behavior than their homogeneous counterparts, and that the power law scaling in the degree distribution is robust in presence of heterogeneity

Voices from the Field

This research study sought to determine the impact from participation in a practicum field experience on teacher candidates’ perceived professional dispositions for effective teaching. A further intent was to describe what teacher candidates perceived to be the necessary professional dispositions for effective teaching as they reflected on their experiences in their particular preparation contexts. A mixed-methods sequential explanatory design was used to examine and understand the development of dispositions from pre-service teachers’ perspectives. The participants consisted of seventeen middle grade undergraduate students who completed over 200 hours of field experience while attending a mid-size university in the Southeastern region of the U.S. The results of a paired-samples t-test showed there was a statistically significant difference on perceived dispositions for effective teaching before practicum experiences and after practicum experiences. From qualitative data analysis, three categories emerged to understand what the pre-service teachers perceived to be professional dispositions for effective teaching: the context for learning, student advocacy, and professional practices. The voices of the seventeen participants in this study provide valuable insights and implications for other teacher education programs who are involved in the planning and development of professional dispositions

GJR Volume 41 Number 1 Spring 2018

The Georgia Journal of Reading\u27s Spring 2018 issue includes: Letter from the Editor by Lina B. Soares (pg. 4) President’s Page by Ron Reigner (pg. 5) Give the Neurological Impress Method Another Chance for One-to-One Fluency Interventions by Melissa M. Mitchell and Dr. Vassiliki Zygouris-Coe (pg. 6) Building Comprehension through Explicit and Organic Vocabulary Instruction for English Learners by Marisa Gonzalez and Dr. Robert A. Griffn (pg. 13) Children’s Literature to Develop Awareness and Advocacy for Social Justice by Dr. Katie Kelly and Dr. Lindsay Yearta (pg. 22) Maximizing Learning: Embedding Phonological Awareness throughout the Day by Dr. Shawnna Helf, Dr. Lindsay Yearta and Dr. Kavin Ming (pg. 30)https://digitalcommons.kennesaw.edu/gjrarchive/1008/thumbnail.jp

GJR Volume 41 Number 2 Winter 2018

The Georgia Journal of Reading\u27s Winter 2018 issue includes: Letter from the Editor by Lina B. Soares (pg. 4) President’s Page by Davetta Grigsby (pg. 5) Teaching to the Test from a Parent’s Perspective by Amy Kettle and Melinda Miller (pg. 6) Reimagining the Traditional Pedagogy of Literacy by Virginie Jackson and Kinsey Shrewsbury (pg. 11) Engaging Strategies for Developing Reading Competencies by Renee Rice Moran, LaShay Jennings., Stacey J. Fisher and Edward J. Dwyer (pg. 24) Taming the Beast: How I Took Back Guided Reading by Laura Sandling (pg. 30)https://digitalcommons.kennesaw.edu/gjrarchive/1007/thumbnail.jp