Effects of Corporate Policies and Governance Practices on Ownership Structure: Evidence from Chilean Firms

We analyze the effects of financing policies, dividends, and corporate governance on ownership structure in Chilean companies. We used a sample of 185 companies listed on the Santiago Stock Exchange that answered the NCG 341 survey on Corporate Governance Practices in 2013. The two-limit Tobit regression (TLTR) results show that debt and dividend policies exert a negative effect on controlling shareholder ownership and a positive effect on minority shareholder ownership. The results show that these policies facilitate control over corporate management determined by the interests of controlling shareholders, as well as protect minority shareholders’ rights by complementing their monitoring role. Corporate governance practices have significant effects on the ownership structure of Chilean companies.Este artículo se propone analizar el impacto de las políticas de financiamiento, dividendos y gobierno corporativo sobre la estructura de propiedad en compañías chilenas. Se usó una muestra de 185 compañías listadas en la Bolsa de Comercio de Santiago, que contestaron la encuesta NCG 341 sobre Prácticas de Gobierno Corporativo en 2013. Los resultados de las regresiones Tobit de dos límites (TLTR) demuestran que las políticas de endeudamiento y de dividendos negativamente afectan la propiedad de los accionistas controladores y protegen los derechos de los accionistas minoritarios al complementar su rol de monitoreo. Las prácticas de gobierno corporativo tienen efectos significativos sobre la estructura de propiedad de las compañías chilenas

The association of at-risk, problem, and pathological gambling with substance use, depression, and arrest history

We examined at-risk, problem, or pathological gambling co-occurrence with frequency of past-year alcohol, tobacco, and marijuana use; depressive symptoms; and arrest history. Data included the responses of over 3,000 individuals who participated in a 2006 telephone survey designed to understand the extent of at-risk, problem, and pathological gambling; comorbidity levels with substance use; mental health; and social problems among Southwestern U.S. residents. Data were analyzed with multinomial and bivariate logistic regression. Respondents at risk for problem gambling were more likely to use alcohol, tobacco, and marijuana than those respondents not at risk. Pathological gamblers were no more or less likely to consume alcohol or tobacco than were non-gamblers or those not at risk. A dose-response relationship existed between degree of gambling problems and depressive symptoms and arrest history. Interventions for at-risk or problem gamblers need to include substance use treatment, and the phenomenon of low levels of substance use among pathological gamblers needs further exploration

Performance analysis of feedback-free collision resolution NDMA protocol

To support communications of a large number of deployed devices while guaranteeing limited signaling load, low energy consumption, and high reliability, future cellular systems require efficient random access protocols. However, how to address the collision resolution at the receiver is still the main bottleneck of these protocols. The network-assisted diversity multiple access (NDMA) protocol solves the issue and attains the highest potential throughput at the cost of keeping devices active to acquire feedback and repeating transmissions until successful decoding. In contrast, another potential approach is the feedback-free NDMA (FF-NDMA) protocol, in which devices do repeat packets in a pre-defined number of consecutive time slots without waiting for feedback associated with repetitions. Here, we investigate the FF-NDMA protocol from a cellular network perspective in order to elucidate under what circumstances this scheme is more energy efficient than NDMA. We characterize analytically the FF-NDMA protocol along with the multipacket reception model and a finite Markov chain. Analytic expressions for throughput, delay, capture probability, energy, and energy efficiency are derived. Then, clues for system design are established according to the different trade-offs studied. Simulation results show that FF-NDMA is more energy efficient than classical NDMA and HARQ-NDMA at low signal-to-noise ratio (SNR) and at medium SNR when the load increases.Peer ReviewedPostprint (published version

La investigación en Bibliometría en la Argentina: quiénes son y qué producen los autores argentinos que realizan estudios bibliométricos

This paper aims to observe and describe the bibliometric research picture in Argentina in the period between 1984 and 2012, based on analysis of the publications of argentine authors located in web search engines, subject repositories and regional and international databases. It interprets forms lining the items studied focusing attention on the following indicators: volume and evolution of scientific production, type of literature, language, subject-matter and analysis unit. It calculates co-authorship index and rates of national and international collaboration. Also it shows the existence of some research groups and the affiliation institutions of main authors, characterizing their research topics and journals and congresses where they published more frequently

La investigación en Bibliometría en la Argentina: quiénes son y qué producen los autores argentinos que realizan estudios bibliométricos

This paper aims to observe and describe the bibliometric research picture in Argentina in the period between 1984 and 2012, based on analysis of the publications of argentine authors located in web search engines, subject repositories and regional and international databases. It interprets forms lining the items studied focusing attention on the following indicators: volume and evolution of scientific production, type of literature, language, subject-matter and analysis unit. It calculates co-authorship index and rates of national and international collaboration. Also it shows the existence of some research groups and the affiliation institutions of main authors, characterizing their research topics and journals and congresses where they published more frequently

Life satisfaction of foreing people in Spain during the economic crisis

En este trabajo pretendemos analizar los determinantes de la satisfacción con la vida de las personas extranjeras en España y las diferencias con las autóctonas. Las preguntas clave son las siguientes: ¿Es más infeliz la población extranjera que la autóctona? ¿Existen diferencias entre los distintos factores relacionados con la felicidad de ambas poblaciones? Los resultados indican que, controlando por variables económicas y sociales, los/as extranjeros/as están más insatisfechos/as que los/as autóctonos/as. Sin embargo, los resultados sugieren que el impacto de la crisis y las diferencias de ingresos condicionan la relación entre ser extranjero/a y la satisfacción con la vida.In this research we analyze the determinants on life satisfaction of foreign people in Spain. The key questions we pose are as follows: Are foreign people more dissatisfied than Spaniards? Are there differences in the factors related to the life satisfaction of foreigners and Spaniards? The results indicate that, controlling for economic and social variables, foreigners are more dissatisfied than the native ones. However, the results suggest that the impact of the crisis, and income differences, condition the relationship between being foreign and satisfaction with life

Perception of speed in biological motion : more resistant to interference?

O sistema visual humano é frequentemente referido como altamente preparado para extrair informação relevante de padrões de movimento biológico. Nesse sentido, este estudo analisa o efeito de contraste na percepção de velocidade. Os participantes realizaram o julgamento de velocidade numa situação na qual dois point-light walkers simultâneos foram apresentados com diferentes contrastes relativamente ao fundo e com diferentes velocidades de translação. Na Experiência 1, o movimento de translação biológico canônico foi comparado com o movimento de translação rígido, enquanto na Experiência 2 ele foi comparado com o movimento de translação biológico invertido. O padrão biológico canônico apresenta maior taxa de erro, tempos de reação mais elevados e maior vulnerabilidade ao efeito de contraste na percepção da velocidade do que o padrão rígido. No entanto, não foram encontradas diferenças significativas entre o estímulo canônico e o invertido. A Experiência 3 foi implementada com o objetivo de se controlar o papel das pistas posicionais na tarefa de julgamento de velocidade. Os pontos iniciais e finais da trajetória foram combinados de modo a que os point-light walkers mais rápidos e os mais lentos pudessem terminar o ensaio numa posição relativamente mais avançada ou atrasada. Apesar desta variação, o padrão de resultados foi congruente com as observações das Experiências 1 e 2. Aparentemente, os participantes realizaram julgamentos de velocidade factuais, ao invés do uso de pistas espaciais como uma espécie de referência ou comparação de posicionamento. Dado que a percepção dos padrões biológicos foi mais vulnerável aos efeitos de contraste, mas não foi afetada pela familiaridade, este estudo sugere que a percepção de movimento biológico e rígido poderá obedecer às mesmas regras computacionais, pelo menos em tarefas que envolvam padrões em translação e julgamentos de velocidade.The human visual system is often referred to as being highly prepared to extract meaningful information from biological motion patterns. In the present study, the contrast effect on speed perception was analysed. Participants performed a test of speed judgment in which two simultaneous point-light walkers were animated at different translational speeds and contrasts in relation to the background. Standard translational biological motion was compared to rigid translational motion in Experiment 1 and to inverted biological motion in Experiment 2. Higher error rates, reaction times and greater vulnerability to contrast effects on speed perception were found for translational biological motion when compared to rigid motion. No significant differences were found, however, between standard and inverted stimuli. Experiment 3 was implemented in order to control the role of positional cues in speed judgment. The start and finish points of the trajectory were varied so that the faster and slower point-light walkers could finish the trial at a relatively more advanced or more withdrawn position. In spite of the variation of the start and finish points of the trajectories, the pattern of results was still consistent with the findings of Experiments 1 and 2. Participants seemed to perform factual speed judgments instead of using spatial cues as a form of reference or positional matching. Since the perception of biological patterns was more sensitive to contrast effects and not affected by familiarity, it is suggested that perception of biological and rigid motion may follow the same computational rules, at least for tasks involving translational patterns and speed judgment.Fundação para a Ciência e a Tecnologia (FCT

Uptake and accumulation of metals in Spartina alterniflora salt marshes from a South American estuary

Salt marshes are capable of reducing metal pollution in coastal waters, but this capacity is highly dependent on the metal, the physico-chemical characteristics of the sediment, the plant species, the production of biomass, the time of the year, etc. The aim of this study was to assess the uptake and accumulation of Pb, Ni, Cu and Zn in Spartina alterniflora from three salt marshes within the Bahía Blanca estuary (BBE), a human-impacted Argentinean system. Metal concentrations in sediments and plants showed the same order at all sites: Zn > Cu > Pb ≥ Ni. The site with lower organic matter and fine sediment content had lower metal concentrations in the sediments, but not a lower metal content in the plant tissues, meaning that the sediment characteristics influenced the metal concentrations in the sediment and their uptake by plants. Despite differences in sediment characteristics between sites, metals were always higher in the belowground tissues than in aboveground ones and, in general, higher in dead than in live tissues. Some metals were accumulated in plant tissues, but not others, and this is dependent on the metal and the sediment characteristics. Allocation patterns of metals in tissues of S. alterniflora were mainly dependent on metal concentrations, determining higher belowground pools, but the aboveground pools were important in some cases due to higher biomass. Partitioning of metals in above or belowground pools determines their fate within the estuarine system, since tissues can decompose in situ (belowground) or be exported (aboveground). Seasonal dynamics were important for some variables but were less noticeable than the differences between sites and tissues. Our results indicate that S. alterniflora from the BBE is efficient in accumulating some metals, despite usually low metal concentrations in sediments and plants. This accumulation capacity has implications for the whole system through the fate of the tissues.Fil: Negrin, Vanesa Lorena. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; Argentina. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia; ArgentinaFil: Botté, Sandra Elizabeth. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; ArgentinaFil: la Colla, Noelia Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; ArgentinaFil: Marcovecchio, Jorge Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; Argentina. Universidad Tecnológica Nacional. Facultad Regional Bahía Blanca; Argentina. Universidad FASTA "Santo Tomas de Aquino"; Argentin

Comportamiento mecánico ante la sobrexpansión de stents de cromo-cobalto comparados con stents de acero inoxidable, implantados en la aorta abdominal de conejos hipercolesterolémicos

Introducción: La fisiopatología de la disfunción diastólica del ventrículo izquierdo incluye alteraciones de la relajación ventricular, rigidez elástica pasiva o una combinación de ambos mecanismos. Mediante el eco-Doppler es posible evaluar parámetros relacionados con la relajación ventricular, pero no de la rigidez elástica pasiva. El estrés parietal diastólico evalúa la rigidez elástica pasiva a través de la disminución de la compresión del miocardio al final de la diástole. Objetivo: Evaluar la rigidez elástica pasiva mediante el estrés parietal diastólico en pacientes con estenosis aórtica grave con fracción de eyección preservada y su relación con la presencia de insuficiencia cardíaca grado III-IV. Material y métodos: Se estudiaron 76 pacientes (edad promedio 67 ± 11 años) portadores de estenosis aórtica grave (índice de área valvular aórtica <0,6 cm2/m2) y fracción de eyección mayor o igual al 50%. El estrés parietal diastólico fue calculado como: (espesor sistólico de pared posterior – espesor diastólico) / espesor sistólico en modo M. Se calculó por métodos no invasivos la relación E/e´, presión de fin de diástole y presión de fin de diástole / volumen de fin de diástole. Los pacientes fueron ordenados en 2 grupos: Grupo 1: insuficiencia cardíaca grado III - IV (n = 5 pacientes) y Grupo 2: sin insuficiencia cardíaca (n = 71 pacientes). Resultados: Los pacientes del grupo 1 presentaron mayor alteración de la rigidez elástica pasiva evidenciada por disminución del estrés parietal diastólico (0,23 ± 0,05 vs. 0,30 ± 0,06 p < 0,01), mayor incremento de E/e´ (20 ± 7 vs. 14 ± 8 p < 0,05), presión de fin de diástole y presión de fin de diástole / volumen de fin de diástole. Conclusión: El estrés parietal diastólico permitiría objetivar alteraciones de la rigidez elástica pasiva en pacientes con estenosis aórtica grave, fracción de eyección preservada e insuficiencia cardíaca que no pueden ser evaluadas mediante los parámetros de función diastólica habituales.Objectives: The aim of this study was to analyze the behavior to overexpansion of cobalt chromium stents compared with stainlesssteel stents.Methods: Twenty New Zealand rabbits were used, fed with a diet supplemented with 1% cholesterol. Animals were divided into twogroups. Group 1 (n=10) received 3.0 mm cobalt chromium stents overexpanded at 20 atmospheres and group 2 (n=10) 3.5 mm stentsdeployed at 10 atmospheres. These stents were compared with a previous series of 20 animals with stainless steel stents, dividedinto the same two groups. A third group with conventional diet was used as control. Intravascular ultrasound (IVUS) was performedto assess the degree of elastic recoil and also the degree of symmetry using ?intertrust angles?.Results: In group 1 of cobalt chromium stents, mean elastic recoil was 0.11±0.13 mm, (3.21% recoil) and in group 2 this was0.3±0.12 mm, (8.26% recoil) (p=0.002). In group 1 of stainless steel stents mean elastic recoil was 0.28±0.18 mm (8.21% recoil) andin group 2 this was 0.10±0.11 mm (2.79% recoil) (p <0.001).Conclusions: In cobalt chromium stents, elastic recoil was lower in overexpanded stents, whereas in stainless steel stents, elasticrecoil was higher in overexpanded stents. No differences in symmetry were observed between the different groups.Fil: Fernandez, Alejandro. Hospital Italiano; ArgentinaFil: Mele, Esteban. Hospital Italiano; ArgentinaFil: Renou, Sandra Judith. Universidad de Buenos Aires. Facultad de Odontología. Cátedra de Anatomía Patológica; ArgentinaFil: Olmedo, Daniel Gustavo. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Odontología. Cátedra de Anatomía Patológica; ArgentinaFil: Berrocal, Daniel. Hospital Italiano; ArgentinaFil: Gelpi, Ricardo Jorge. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Odontología. Cátedra de Anatomía Patológica; Argentin