Nonlinear Dynamic in the Chilean Stock Market: Evidence from Returns and Trading Volume

In this paper we investigate the possible presence of nonlinear dynamics for stock index returns and trading volume at the Chilean Stock Market. To capture any nonlinear behavior in the series we estimate Smooth Transition Autoregressive (STAR) models and test them against the linear alternatives. As a complement to this univariate approach, we use Markov-Switching Vector Autoregressive (MS-VAR) models to investigate the empirical relationship between both variables. The results clearly show that the Chilean Stock Market is characterized by the presence of nonlinear patters in both series (trading volume and stock returns) as well as in their joint relationship. The presence of nonlinearities is a key issue in testing the Efficient Market Hypothesis (EMH), according to which stock returns and trading volume should be not related. Previous researches on the efficiency using data from the Chilean stock market, using linear models, support the hypothesis. However, the nonlinear patters we found in the data are a clear signal of misspecification problems in a testing procedure based on a linear approach.

Non-linear Dynamics in the Chilean Stock Market: Evidence on Traded Volumes and Returns

In this paper we investigate the possible presence of nonlinear dynamics for stock index returns and trading volume in the Chilean stock market. To capture any nonlinear behavior of the series we estimate smooth transition autoregressive (STAR) models and then test them against the linear alternatives. As a complement to this univariate approach, we use Markov-Switching Vector Autoregressive (MS-VAR) models to investigate the empirical relationship between both variables. The results clearly show that the Chilean Stock Market is characterized by the presence of nonlinear patterns in both series (trading volume and stock returns) as well as in their joint relationship. The presence of nonlinearities is a key issue in testing the Efficient Market Hypothesis (EMH), according to which stock returns and trading volume should not be related. Previous research on the efficiency using data from the Chilean stock market, based on linear models, support the hypothesis. However, the nonlinear patters found in the data are a clear signal of misspecification problems in a testing procedure based on a linear approach.

BioMeT and algorithm challenges: A proposed digital standardized evaluation framework

Technology is advancing at an extraordinary rate. Continuous flows of novel data are being generated with the potential to revolutionize how we better identify, treat, manage, and prevent disease across therapeutic areas. However, lack of security of confidence in digital health technologies is hampering adoption, particularly for biometric monitoring technologies (BioMeTs) where frontline healthcare professionals are struggling to determine which BioMeTs are fit-for-purpose and in which context. Here, we discuss the challenges to adoption and offer pragmatic guidance regarding BioMeTs, cumulating in a proposed framework to advance their development and deployment in healthcare, health research, and health promotion. Furthermore, the framework proposes a process to establish an audit trail of BioMeTs (hardware and algorithms), to instill trust amongst multidisciplinary users

Efecto de la utilización de diferentes proporciones de sustrato y edad de la planta (1 y 2 años) de frutilla chilena (Fragaria chiloensis) en rendimiento y calidad del fruto

56 p.Fragaria chiloensis es una especie nativa de Chile, posee cualidades organolépticas distintivas como su acentuado aroma y sabor, así un corto periodo de cosecha. El uso de diferentes proporciones de pino compostado con perlita alteraría la extensión del periodo de cosecha, rendimiento y calidad de plantas de frutilla chilena (Fragaria chiloensis) cultivadas en hidroponía bajo invernadero. El presente estudio se realizó durante la temporada 2010-2011 en invernaderos de la Estación Experimental Panguilemo de la Universidad de Talca (35º 26` L.S.; 71º41` L.W.; 90 m.s.n.m.), para determinar la influencia del sustrato sobre la extensión del periodo de cosecha, rendimiento y calidad de Fragaria chiloensis en plantas de primer y segundo año en un sistema hidropónico. Los sustratos utilizados fueron pino compostado y perlita en proporción 3:1, 2:1 y 1:1. Se estableció un arreglo factorial de 3 x 2 (3 mezclas de sustrato; 2 edades de planta de F. chiloensis) en un diseño completamente al azar. La unidad experimental fue una canaleta de 3 m de largo, 0,2 m de alto y 0,3 m de ancho con 15 plantas de primer año y 15 plantas de segundo año. Hubo evaluaciones semanales del número de botones florales, flores abiertas, flores cuajadas, flores muertas, frutos verdes, frutos maduros, materia seca de estolones y número de estolones. El número de frutos cosechados, peso y diámetros de frutos y sólidos solubles se midió diariamente durante el período de cosecha. Los resultados obtenidos indican que no existió interacción entre edad de planta y proporción del sustrato para las variables medidas. No hubo diferencias significativas en las distintas proporciones de pino compostado y perlita, tanto en plantas de primer como de segundo año para peso, sólidos solubles y diámetro del fruto, obteniéndose en promedio 6,2 g/fruto, 8,8 ° Brix y 21,64 mm, respectivamente. Existieron diferencias significativas en el rendimiento entre plantas de primer y segundo año, obteniendo 8,1 g/planta y 56,1 g/planta en promedio, respectivamente. En la investigación se presentó una extensión del periodo de cosecha de siete días en plantas de frutilla chilena (Fragaria chiloensis), tanto de primer como de segundo año para las distintas proporciones de pino compostado y perlita./ABSTRACT : Fragaria chiloensis is a native plant of Chile, with distintctive organoleptic qualities such as aroma and flavor, and a short harvest period. The use of different ratios of composted pine with perlite would alter the extent of the harvest period, yield and quality of Chilean strawberry plants (Fragaria chiloensis) grown in hydroponic under a cold greenhouse. This study was carried put during the 2010-2011 season in greenhouses at the Experimental Station Panguilemo in the Universidad de Talca (35 º 26 'LS, 71 º 41' LW, 90 m), to determine the influence of substrate on extending the harvest period, yield and quality of Fragaria chiloensis plants of first and second year in a hydroponic system. The substrates utilised were pine compost and perlite in ratios: 3:1, 2:1 and 1:1. The experimental design was a factorial arrangement of 3 x 2 (3 substrate mixtures, 2 plant ages of F. chiloensis) in a completely randomized design. The experimental unit was composed of 15 plants of first year and 15 plants of second year established in a trough 3 m long, 0.2 m high and 0.3 m wide. There were weekly assessments of the number of flower buds, open flowers, fruit set, dead flowers, green fruit, ripe fruit, dry matter of stolons and number of stolons. The number of harvested fruits, fruit weight and diameter and soluble solids was measured daily during the harvest period. The results obtained indicate that there was no interaction between age of plant and proportion of the substrate for the measured variables. No significant differences in the different proportions of composted pine and perlite, for both plants first and second year in weight, soluble solids and fruit diameter, yielding an average of 6.2 g / fruit, 8.8° Brix and 21.64 mm, respectively. There were significant differences in performance for one and two year old plants, giving 8.1 g / plant and 56.1 g / plant on average, respectively. There was an extension of the harvest period of seven days in Chilean strawberry plants (Fragaria chiloensis), both for first and second years plants for the different ratios of composted pine and perlite

Current and potential distribution areas for Nothofagus alessandrii, an endangered tree species from central Chile

Nothofagus alessandrii ("ruil") is an endangered species native to the Maule Coastal Forest of central Chile. Previous studies have demonstrated that the current distribution of this species and rates of deforestation and fragmentation present a serious threat to the species. To address this threat, spatial and temporal variation in remnant "ruil" forest cover was analyzed for the period from 1991 to 2008. Using aerial photography and geomatic tools, the state of "ruil" forests cover in 1991 was compared to the "ruil" forests cover in 2008 and with this information, the potential distribution area of this species was calculated. The results demonstrate that the current area of "ruil" forest is approximately 314 ha, with a net loss of 42 ha (12% of the forested area) over the 17-year study period. The annual deforestation rate for "ruil" during this period was 0.74%, a value that is significantly lower than that reported just two decades ago. Taken together with the fact that the majority of "ruil" forests belong to large private companies, with an additional 15% protected by the Chilean government, the conservation status of "ruil" forest has become less critical, at least in the short term. In addition, the habitat model from this study showed that there is a large area of 9,841 ha within which "ruil" forests could be greatly expanded through active forest restoration

CONTROL OF A QUADRUPED LEG USING AN ANALYTICAL APPROACH

The objective of this work is to test the performance of a swing leg controller in simulation using the Simulink software. The main contribution of this controller is that in literature it has been tested a controller with another approach, while it will be proposed another controller with a feedforward term as well, using a different approach. This controller was tested in simulation in order to prove its behavior and its performance

Pleistocene uplift, climate and morphological segmentation of the northern Chile coasts (24°S-32°S): Insights from cosmogenic 10Be dating of paleoshorelines

International audienceWe present new cosmogenic (10Be) exposure ages obtained on Pleistocene marine abrasion shore terraces of Northern Chile between 24°S and 32°S in order to evaluate the temporal and spatial variability of uplift rates along the coastal forearc. Both the dispersion of cosmogenic concentrations in samples from the same terrace and data obtained in vertical profiles show that onshore erosion rates, following emergence of paleoshorelines, approached 1 m/Myr. Therefore, minimum ages calculated without considering onshore erosion may be largely underestimated for Middle Pleistocene terraces. The elevation of the last interglacial (MIS-5) paleoshoreline is generally between 25 and 45 m amsl, suggesting that the entire coast of the study area has been uplifting during the Upper Pleistocene at rates approaching 0.3 mm/yr. Available ages for Middle Pleistocene terraces suggest similar uplift rates, except in the Altos de Talinay area where uplift may have been accelerated by the activity of the Puerto Aldea Fault. The maximum elevation of Pleistocene paleoshorelines is generally close to 250 m and there is no higher older Neogene marine sediment, which implies that uplift accelerated during the Pleistocene following a period of coastal stability or subsidence. We observe that the coastal morphology largely depends on the latitudinal climatic variability. North of 26.75°S, the coast is characterized by the presence of a high scarp associated with small and poorly preserved paleoshorelines at its foot. The existence of the coastal scarp in the northern part of the study area is permitted by the hyper-arid climate of the Atacama Desert. This particular morphology may explain why paleoshorelines evidencing coastal uplift are poorly preserved between 26.75°S and 24°S despite Upper Pleistocene uplift rates being comparable with those prevailing in the southern part of the study area

EFFECT OF THE PANTANAL’S FLOODING HISTORY IN MORPHOMETRIC ASPECTS OF THE SOLITARY PARASITOID Campsomeris dorsata (HYMENOPTERA: SCOLIIDAE)

The shape of an organism and the variation between related groups lie at the core of understanding evolution and interactions between phenotypes, genotypes, and environmental spaces. Due to the relief conditions and hydrological profile of the region, the areas inside the Pantanal have different flood histories in respect to the flood duration and the amount of water retained in the plain. The objective of this work was to evaluate the effect of the environmental flooding gradient on the geometric morphometry variation of Campsomeris dorsata (Hymenoptera: Scoliidae) wings in Pantanal, to understand if the variations in spatial distribution related to the flooding history interferes in the morphology of the wings by identifying where, how, and to what magnitude such changes occur. The wings were mounted between blade and coverslip, labeled, and prepared for morphometric measurements. The points of intersection of wing veins (landmarks) were determined using a stereoscopic microscope coupled with a camera. The linear measurements of the landmarks were transformed using Procrustes to remove the size effect, leaving only the shape of the wings. The transformed data was evaluated using PCA and MANOVA to identify if there were differences in relation to the geographical location of occurrence. Thirty-three male C. dorsata wings were measured, and there was a clear separation between 3 distinct wing form groups along the Pantanal distribution. The variation in wing shape could be associated with selection from local environmental conditions in areas with distinct flooding histories, influencing migratory aspects among populations within the Brazilian Pantanal. The data for this small species, that has low dispersal capacity, is solitary, and presents an intimate relationship with soil characteristics, which directly reflects flooding aspects in the Pantanal, only reinforces the need to conserve more areas in the Brazilian Pantanal, since genetic diversity is an important factor for conservation