Diving behaviour of the critically endangered tope shark Galeorhinus galeus in the Natural Reserve of Bahia San Blas, northern Patagonia

Background:Tope sharks (Galeorhinus galeus) aggregate in large numbers during spring and summer in closedgulfs and bays in northern Patagonia; these locations are considered the main nursery areas for the species.However, little is known about the spatial ecology or diel behaviour of this critically endangered species. The aimwas to evaluate the short-term diving behaviour and habitat preferences of tope sharks using electronic tagging.Findings:Five female tope sharks, four adult and one sub-adult, were tagged with pop-up satellite archival tags inthe Natural Reserve of Bahía San Blas, northern Patagonia, during spring 2011 and 2012. High-resolution archiveddata were collected for 40 days, including 29 days for two recovered tags. Sharks travelled up to 51.2 km after release.Archived data indicated that female tope sharks preferred to remain within 24.5 m of the surface and that there wereno diel changes in preference. Individuals spent most of the time within 10 m of the surface during the day (80%) andat night (83%), and were primarily in water between 17°C and 19°C (day, 75%; night, 70%). Moreover, tope sharksexhibited vertical oscillatory movement (‘yo-yo diving’). Maximum vertical speeds and dive depths were recordedat night. Ascents from depth had a greater speed than descents, overall.Conclusions:Female tope sharks were found in shallow coastal areas during November at Bahía San Blas, near thesurface at relatively restricted depths and temperatures. Longer tracking periods will be important for describingthe species’migratory movements across the south-west Atlantic.Fil: Cuevas, Juan Martín. Universidad Nacional de la Matanza. Instituto de Medio Ambiente; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo; Argentina. Universidad Nacional del Comahue. Instituto de Biología Marina y Pesquera Almirante Storni; ArgentinaFil: Garcia, Mirta Lidia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo; ArgentinaFil: Di Giacomo, Edgardo Ernesto. Universidad Nacional del Comahue. Instituto de Biología Marina y Pesquera Almirante Storni; Argentin

Diving behaviour of the critically endangered tope shark Galeorhinus galeus in the Natural Reserve of Bahia San Blas, northern Patagonia

Background: Tope sharks (Galeorhinus galeus) aggregate in large numbers during spring and summer in closed gulfs and bays in northern Patagonia; these locations are considered the main nursery areas for the species. However, little is known about the spatial ecology or diel behaviour of this critically endangered species. The aim was to evaluate the short-term diving behaviour and habitat preferences of tope sharks using electronic tagging. Findings: Five female tope sharks, four adult and one sub-adult, were tagged with pop-up satellite archival tags in the Natural Reserve of Bahía San Blas, northern Patagonia, during spring 2011 and 2012. High-resolution archived data were collected for 40 days, including 29 days for two recovered tags. Sharks travelled up to 51.2km after release. Archived data indicated that female tope sharks preferred to remain within 24.5m of the surface and that there were no diel changes in preference. Individuals spent most of the time within 10m of the surface during the day (80%) and at night (83%), and were primarily in water between 17°C and 19°C (day, 75%; night, 70%). Moreover, tope sharks exhibited vertical oscillatory movement ('yo-yo diving'). Maximum vertical speeds and dive depths were recorded at night. Ascents from depth had a greater speed than descents, overall. Conclusions: Female tope sharks were found in shallow coastal areas during November at Bahía San Blas, near the surface at relatively restricted depths and temperatures. Longer tracking periods will be important for describing the species' migratory movements across the south-west Atlantic.Facultad de Ciencias Naturales y Muse

The influence of school time in the academic achievement: a comparative study in educational systems of Europe and Latin America

Los sistemas educativos están estructurados a tenor de múltiples factores que lo condicionan y determinan. Entre los diferentes aspectos, el tiempo juega un papel clave al marcar la duración de cada una de las diferentes etapas educativas y del proceso de enseñanza-aprendizaje durante las mismas. Partiendo de esta realidad, este trabajo pretende analizar el tiempo escolar y su influencia en el rendimiento académico, considerándolo un factor clave de la calidad educativa. Para ello, se ha llevado a cabo un estudio comparativo entre varios países europeos (Finlandia, Austria, Francia y España) y latinoamericanos (Chile, México y Colombia) que han participado en el Programa para la Evaluación Internacional de los Alumnos (PISA). A partir de los resultados académicos de PISA, pretendemos analizar cómo influyen las horas de instrucción obligatoria (Primaria y Secundaria) en el rendimiento académico del alumnado. Entre los resultados obtenidos, podemos destacar que el simple incremento de la carga horaria en las diferentes etapas educativas no influye positivamente en el rendimiento académico de los alumnos. Por el contrario, cobra mayor relevancia la forma de abordar el proceso de enseñanza-aprendizaje (lo que hacemos como profesionales de la educación en el aula) que el tiempo que se emplee en ello.Educational systems are structured under multiple factors that condition and determine. Between different aspects, the time plays a key role to set the duration of each of the different educational stages and the teaching-learning process for them. Starting from this reality, this paper analyzes the school time and its influence on the academic performance, as one of the main factors in the quality of education. For this, it has been carried out a comparative study of several European countries (Finland, Austria, France and Spain) and Latin American countries (Chile, Mexico and Colombia) have participated in the Programme for International Student Assessment (PISA). From the academic results of PISA, we analyze how influences the hours of compulsory education (Primary and Secondary) in student performance. Between the results obtained, we can stand out that simply increasing the number of hours in the different educational stages no positive effect in student performance. Inversely, becomes more important the way of approach the teaching-learning process (whatever we as professional education in the classroom) that the time used in it

Plan de negocios como estrategia de comercialización para una agroindustria de dulces de leche

Las empresas en la actualidad son de fundamental valor para nuestra economía, de ahí la importancia del objeto de estudio, es evidente que subsisten múltiples y variados conceptos o interpretaciones referentes a la empresa. Sin embargo, las empresas pueden entrar en varios rubros de las diferentes clasificaciones, dependiendo ya sea del empresario, o del servicio o giro en el que se encuentre

PROPINA ENTRE DÁDIVA O BENEFICIO: FACTORES DETERMINANTES EN UN CONTEXTO FRONTERIZO

Tipping has become a unilateral gratification paid by the client reciprocating the service provider for a good service, to a moral obligation to a service that sometimes does not comply with quality standards. Even though it is true that in some countries the tip is mandatory based on a percentage of the account payable, regardless of the service received, in other countries it is not. However, in countries like Mexico it is customary to pay it based on a percentage and sometimes this percentage depends on the quality of the service received. Mexican legislation does not make tipping mandatory, but the border areas live in a mix of Mexican and American cultures and traditions, making tips a percentage of the consumption

El desarrollo laboral sustentable y su relación con la migración interna en México

En este trabajo se estudió la interacción entre la migración interestatal y el desarrollo laboral sustentable en México del año 2000 al 2010, de acuerdo con la visión de Amartya Sen. Este desarrollo se midió con el índice de competitividad social, y la interacción con la migración interna se evaluó con un modelo de ecuaciones simultáneas. Los resultados confirmaron que a mayor desarrollo laboral sustentable, el grado de inmigración fue más y viceversa. Por otro lado, no se encontró relación alguna entre la emigración interna y el desarrollo laboral sustentable. Al desagregar el índice de competitividad social, se encontró una relación causal mutua entre el índice de la ausencia de pobreza salarial y la inmigración interna, así como una relación causa-efecto positiva entre ausencia de pobreza salarial sobre la emigración interna, la cual no se da en el otro sentido

Effect of two oil types and energy levels on broiler performance, carcass quality and skin pigmentation

This study evaluated different levels of metabolisable energy (ME) and two oil types: crude soybean oil (CSO) and acidulated soybean oil (ASO), in sorghum-soybean meal diets for broilers. One thousand and eight unsexed Ross 308 chicks aged 1 to 49 days old were used in a factorial arrangement design 2x3. The first factor corresponded to the oils (CSO and ASO) and the second factor corresponded to the ME levels (high, medium and low) in the initiation (1-10 days), growing (11-25 days) and finishing (26-48 days) feeds, with a 90 kcal/kg reduction. The treatments were as follows: (1) CSO with 3010, 3175 and 3200 kcal/kg; (2) CSO with 2920, 3085 and 3110 kcal/kg; (3) CSO with 2920, 3085 and 3200 kcal/kg; (4) ASO with 3010, 3175 and 3200 kcal/kg; (5) ASO with 2920, 3085 and 3110 kcal/kg; and (6) ASO with 2920, 3085 and 3200 kcal/kg. The treatments with high and medium levels of ME (P<0.05) were higher. The carcass weight and skin pigmentation when cold were better in broilers fed with high and medium levels of ME (P<0.05). No effect (P>0.05) between oil types was found. It can be concluded that it is feasible to replace CSO by ASO and to reduce 90 kcal/kg of ME from the recommended amount for the breed during the initiation and growing stages, without affecting their performance

Biodisponibilidad de lisina en dos pastas de soya con diferente nivel de actividad ureásica en pollos de engorda

In  order  to  study  bioavailability  of  lysine  of  two  soybeans  meals  (PSA  and  PSB)  for  broilers  with  different  ureaseactivity  (UA of  0.11 and  0.17 units  of  pH change),  an experiment  was  performed.  Two  hundred  and  ten (210)  chicksRoss  were  used  from  1  to  21  d  of  age,  in  a  completely  randomized  design  with  7  treatments  with  three  replicateseach  one. Treatments  were: 1)  Basal  diet sorghum-soybean  meal (deficient  in  lysine), 2)  Basal  diet+0.05%  L-lysine,3)  Basal diet+0.10%  L-lysine,  4) Basal  diet+0.05%  lysine from  PSA, 5)  Basal  diet+0.10% lysine  from  PSA,  6)  Basaldiet+0.05%  lysine from  PSB and  7)  Basal diet+0.10%  lysine  from  PSB.  The  growth  results  obtained  were  explainedby multiple linear regression equation, based on the data of weight gain, consumption of synthetic lysine  and intakesof  lysine  from  soybean  meals:  Y=X1+  Y=  375.419  +  0.0378  X1  +  0.0366  X2  +  0.0376  X3;  where  X1  accountedsupplementation  with  L-lysine,  X2  with  PSA  (with  addition  of  raw  hull)  and  X3  with  PSB  (with  addition  of  cockedhull).  Comparison  of  the  PSA  or  PSB  slopes  with  the  L-lysine  slope  (i.e.  100  %  bioavailability)  showed  them  all  tohave  >95  %  lysine  availability:  PS  A=  97  %,  PSB=  99  %.  These  results  indicate  that  UA  of  soybean  meal  affectedthe  bioavailability  of  lysine;  therefore  more  than  0.12  urcase  activity  units  of  pH  change,  lower  is  the  availability.Para conocer la biodisponibilidad de lisina para pollos de dos pastas de soya (PSA y PSB), con diferente actividad ureásica (AU 0.11 y 0.17 unidades de incremento de pH), se realizó el presente experimento. Se utilizaron 210 pollitos Ross de 1 a 21 días de edad, los cuales se distribuyeron al azar en 7 tratamientos con tres repeticiones. Lostratamientos fueron: 1) dieta basal sorgo-soya-ajonjolí (deficiente en lisina), 2) dieta basal + 0.05% de L-lisina, 3) dieta basal+0.10% de L-lisina, 4) dieta basal+0.05% de lisina a partir de PSA, 5) dieta basal+0.10% de lisina a partir de PSA, 6) dieta basal+0.05% de lisina a partir de PSB y 7) dieta basal+0.10% de lisina a partir de PSB. Losresultados de crecimiento, se explicaron mediante la ecuación de regresión lineal múltiple, con los datos de ganancia de peso, consumos de lisina sintética o consumos de lisina a partir de las pastas de soya fue Y= 375.419 + 0.0378 X1 + 0.0366 X2 + 0.0376 X3; en donde X1 correspondió a la complementación con L-lisina, X2 con la PSA (con adición de cascarilla cruda) y X3 con la PSB (con adición de cascarilla cocida). Al comparar la pendiente de la pasta de soya A o B, con la obtenida con L-lisina (100%), se tuvieron biodisponibilidades de lisina de 97 y 99 % para las pastasde soya A y B respectivamente. Estos resultados indican que la AU de la pasta de soya afecta la biodisponibilidad de lisina; a mayor actividad ureásica, menor es la disponibilidad

Time measurement characterization of stand-to-sit and sit-to-stand transitions by using a smartphone

The aim of this study is to analyze a common method to measure the acceleration of a daily activity pattern by using a smartphone. In this sense, a numerical approach is proposed to transform the relative acceleration signal, recorded by a triaxial accelerometer, into an acceleration referred to an inertial reference. The integration of this acceleration allows to determine the velocity and position with respect to an inertial reference. Two different kinematic parameters are suggested to characterize the profile of the velocity during the sit-to-stand and stand-to-sit transitions for Parkinson and control subjects. The results show that a dimensionless kinematic parameter, which is linked to the time of sit-to-stand and stand-to-sit transitions, has the potential to differentiate between Parkinson and control subjects.Peer ReviewedPreprin