140 research outputs found

    The economic cost of losing native pollinator species for orchard prodution

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    The alarming loss of pollinator diversity world‐wide can reduce the productivity of pollinator‐dependent crops, which could have economic impacts. However, it is unclear to what extent the loss of a key native pollinator species affects crop production and farmer's profits. By experimentally manipulating the presence of colonies of a native bumblebee species Bombus pauloensis in eight apple orchards in South Argentina, we evaluated the impact of losing natural populations of a key native pollinator group on (a) crop yield, (b) pollination quality, and (c) farmer's profit. To do so, we performed a factorial experiment of pollinator exclusion (yes/no) and hand pollination (yes/no). Our results showed that biotic pollination increased ripe fruit set by 13% when compared to non‐biotic pollination. Additionally, fruit set and the number of fruits per apple tree was reduced by less than a half in those orchards where bumblebees were absent, even when honeybees were present at high densities. Consequently, farmer's profit was 2.4‐fold lower in farms lacking bumblebees than in farms hosting both pollinator species. The pollination experiment further suggested that the benefits of bumblebees could be mediated by improved pollen quality rather than quantity. Synthesis and applications. This study highlights the pervasive consequences of losing key pollinator functional groups, such as bumblebees, for apple production and local economies. Adopting pollinator‐friendly practices such as minimizing the use of synthetic inputs or restoring/maintaining semi‐natural habitats at farm and landscape scales, will have the double advantage of promoting biodiversity conservation, and increasing crop productivity and profitability for local farmers. Yet because the implementation of these practices can take time to deliver results, the management of native pollinator species can be a provisional complementary strategy to increase economic profitability of apple growers in the short term.info:eu-repo/semantics/acceptedVersio

    Beneficios económicos de la cacería de lagarto (Caiman yacaré) en la Amazonía boliviana

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    El aprovechamiento legal del lagarto (Caiman yacare) representa una alternativa económica en las tierras bajas de la Amazonia boliviana. La cacería se enmarca en el Programa para la Conservación y Aprovechamiento Sostenible del Lagarto, que ya tiene vigencia durante más de una década. Sin embargo, son escasas las evaluaciones de los beneficios sociales, económicos y culturales que brinda el programa. En el presente trabajo se evalúa los beneficios económicos logrados por los cazadores de la comunidad campesina Bella Vista, situada en la provincia Iténez, antes de la elaboración del plan de manejo de lagarto de la zona sur del área protegida PD ANMI Iténez (2007), durante la fase de elaboración del plan (2008-2009) y después de su aprobación mediante Resolución Ministerial (2010). En este intervalo de tiempo los cupos aprovechados por los cazadores de Bella Vista subieron de 246 a 680 lagartos. Los beneficios económicos para los cazadores estuvieron determinados en mayor grado por las fluctuaciones en los precios ofertados por las empresas industriales que compran los chalecos. El valor económico en los mercados de un lagarto de aproximadamente 1.80 m de longitud bajó de aproximadamente 140 Bs (20 US)a70Bs(10US) a 70 Bs (10 US) entre 2008 y 2010. El plan de manejo y el fortalecimiento organizativo de los cazadores han contribuido a mantener controlado el impacto a nivel local de la caída de los precios. Se presentan las estrategias de aprovechamiento sostenible de la especie en la región.A exploração legal do jacaré (Caiman yacare) representa urna alternativa económica em algumas regiões da Amazonia boliviana. A caça é parte do Programa de Conservação e Uso Sustentável do Jacaré, que está vigente por mais de urna década. No entanto, são escassas as avaliações dos beneficios sociais, económicos e culturais fomecidos pelo programa. O presente trabalho avalia os beneficios económicos obtidos pelos caçadores da comunidade rural Bella Vista, localizada na provincia Iténez, antes da elaboração do Plano de Manejo do Jacaré da zona sul da área protegida PD ANMI Iténez (2007), após a elaboração do plano (2008-2009) e depois da sua aprovação (2010). Neste período, a quota de explora9ao aumentou de 236 a 680. Os beneficios foram determinados em maior grau pelas oscila9óes nos preços oferecidos pelas empresas que compram peles de jacarés, variando, entre 2008 e 2010, de 140 Bs (20 US)a70Bs(10US) a 70 Bs (10 US) para um jacaré de aproximadamente 1,80 m de comprimento. Graças ao plano de manejo e ao fortalecimento organizacional dos ca9adores, o impacto local do decréscimo dos pre90s tem sido controlado. Assim, são apresentadas as estratégias de exploração sustentável da espécie na região.The legal hunting of yacaré caiman (Calman yacare) represents an economic altemative in the lowlands of the Bolivian Amazon. Caiman hunting is implemented within the framework of the National Program for Conservation and Sustainable Use of Yacare Caiman, which has been in place for more than a decade. However, evaluations of the program’s social, economic and cultural benefits are scarce. This document evaluates the economic benefits gained by hunters from the farming community of Bella Vista, situated in the province of Iténez, department of Beni (northeast of the Bolivian Amazon) during three phases: before the elaboration of the caiman management plan in the area (Departmental Park Natural Area for Integrated Management PD ANMI Iténez) (2007), during its elaboration (2008-2009) and after plan approval (2010). Between 2007 and 2010 the hunting quota for the community increased from 246 to 680. The economic benefits are determined to a large extent by fluctuations in prices offered by the industrial tanneries. These prices decreased significantly between 2008 and 2010 thus being the main factor responsible for diminished benefits for local hunters. Between 2008 and 2010, the value of one caiman measuring 1.8 m decreased from 20 US(140Bs)to10US (140 Bs) to 10 US (70 Bs). The available data suggest that the management plan and the strengthening of local hunting organizations helped to buffer the negative tendency in prices. Sustainable hunting strategies for the yacare caiman in the region are presented

    Quantificação de Bisfenol-A livre em sangue de cordão umbilical humano a nível de traços

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    El Bisfenol-A (BPA) es ampliamente utilizado en la producción de plásticos de policarbonato, por lo que está presente en productos de uso masivo. Es un disruptor endócrino e incide en el desarrollo gonadal y del sistema nervioso central. La exposición de mujeres embarazadas al BPA es particularmente preocupante para el feto en desarrollo, debido a que atraviesa la placenta pasando a la sangre de cordón y al líquido amniótico. Esto se suma a la escasa o nula actividad enzimática fetal para biotransformarlo en BPAglucurónido inactivo, causando posibles efectos nocivos a la descendencia a dosis muy bajas y sostenidas. Con el propósito de estudiar la exposición al BPA y sus efectos en la población de Argentina se desarrolló y validó un método analítico por cromatografía líquida acoplada a espectrometría de masa, que permite la cuantificación de trazas de BPA libre (forma estrogénica, activa) en plasma de cordón umbilical. La técnica consiste en la precipitación de proteínas de la sangre de cordón por agregado de acetonitrilo y posterior centrifugado e inyección del sobrenadante. Se utilizó una elución isocrática en la cromatografía líquida, y la espectrometría de masa se realizó empleando Electrospray negativo en modo de monitoreo de reacciones múltiples. Los valores de BPA libre cuantificados están en el rango de 1,0 a 12,1 ng/mL, límite de detección: 0,6 ng/mL.Bisphenol-A (BPA) is widely used in the production of polycarbonate plastics and therefore, it is present in products of massive use. It is known as an endocrine disruptor and has an impact on gonadal and central nervous system development. Exposure of pregnant women to BPA is particularly worrying for the developing fetus because it crosses the placenta into the cord blood and amniotic fluid, coupled with little or no fetal enzymatic activity to biotransform it into inactive BPA-glucuronide, causing possible harmful effects to the offspring at very low and sustained doses. With the aim to study the exposure to BPA and its effects on the population of Argentina, an analytical method was developed and validated by liquid chromatography coupled to mass spectrometry, which allows the quantification of trace amounts of free BPA (estrogenic, active form) in plasma of umbilical cord. The method involves protein precipitation by the addition of acetonitrile and subsequent centrifugation and injection of supernatant. An isocratic elution was used in liquid chromatography, and mass spectrometry was performed using negative Electrospray mode in multiple reaction monitoring. Quantified free BPA values are in the range of 1.0 to 12.1 ng/mL, Detection Limit: 0,6 ng/mL.Fil: Cases, Gabriel Guillermo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Unidad de Microanálisis y Métodos Físicos en Química Orgánica. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Unidad de Microanálisis y Métodos Físicos en Química Orgánica; Argentina. Hospital Italiano; ArgentinaFil: Calinski, Gustavo J.. Hospital Italiano; ArgentinaFil: Méndez, Mariana L.. Hospital Italiano; ArgentinaFil: Vidal, Flavia A.. Hospital Italiano; ArgentinaFil: Otaño, Lucas. Hospital Italiano; ArgentinaFil: Mariani, Gonzalo L.. Hospital Italiano; ArgentinaFil: Figar, Silvana. Hospital Italiano; ArgentinaFil: Giménez, María I.. Hospital Italiano; Argentin

    Mitochondrial phosphoenolpyruvate carboxykinase (PEPCK-M) and serine biosynthetic pathway genes are co-ordinately increased during anabolic agent-induced skeletal muscle growth

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    We aimed to identify novel molecular mechanisms for muscle growth during administration of anabolic agents. Growing pigs (Duroc/(Landrace/Large-White)) were administered Ractopamine (a beta-adrenergic agonist; BA; 20ppm in feed) or Reporcin (recombinant growth hormone; GH; 10mg/48hours injected) and compared to a control cohort (feed only; no injections) over a 27-day time course (1, 3, 7, 13 or 27-days). Longissimus Dorsi muscle gene expression was analyzed using Agilent porcine transcriptome microarrays and clusters of genes displaying similar expression profiles were identified using a modified maSigPro clustering algorithm. Anabolic agents increased carcass (p=0.002) and muscle weights (Vastus Lateralis: p<0.001; Semitendinosus: p=0.075). Skeletal muscle mRNA expression of serine/one-carbon/glycine biosynthesis pathway genes (Phgdh, Psat1 and Psph) and the gluconeogenic enzyme, phosphoenolpyruvate carboxykinase-M (Pck2/PEPCK-M), increased during treatment with BA, and to a lesser extent GH (p<0.001, treatment x time interaction). Treatment with BA, but not GH, caused a 2-fold increase in phosphoglycerate dehydrogenase (PHGDH) protein expression at days 3 (p<0.05) and 7 (p<0.01), and a 2-fold increase in PEPCK-M protein expression at day 7 (p<0.01). BA treated pigs exhibit a profound increase in expression of PHGDH and PEPCK-M in skeletal muscle, implicating a role for biosynthetic metabolic pathways in muscle growth

    A Milky Way-like barred spiral galaxy at a redshift of 3

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    International audienceThe majority of massive disk galaxies in the local Universe show a stellar barred structure in their central regions, including our Milky Way. Bars are supposed to develop in dynamically cold stellar disks at low redshift, as the strong gas turbulence typical of disk galaxies at high redshift suppresses or delays bar formation. Moreover, simulations predict bars to be almost absent beyond z=1.5z = 1.5 in the progenitors of Milky Way-like galaxies. Here we report observations of ceers-2112, a barred spiral galaxy at redshift zphot3z_{\rm phot} \sim 3, which was already mature when the Universe was only 2 Gyr old. The stellar mass (M=3.9×109MM_{\star} = 3.9 \times 10^9 M_{\odot}) and barred morphology mean that ceers-2112 can be considered a progenitor of the Milky Way, in terms of both structure and mass-assembly history in the first 2 Gyr of the Universe, and was the closest in mass in the first 4 Gyr. We infer that baryons in galaxies could have already dominated over dark matter at z3z \sim 3, that high-redshift bars could form in approximately 400 Myr and that dynamically cold stellar disks could have been in place by redshift z=45z = 4-5 (more than 12 Gyrs ago)

    Desynchronization of Neocortical Networks by Asynchronous Release of GABA at Autaptic and Synaptic Contacts from Fast-Spiking Interneurons

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    An activity-dependent long-lasting asynchronous release of GABA from identified fast-spiking inhibitory neurons in the neocortex can impair the reliability and temporal precision of activity in a cortical network

    Modelos de combustibles para arbustales de la Región Andina de las provincias de Río Negro, Chubut y Santa Cruz

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    En este folleto de divulgación, se dan a conocer las principales herramientas para el modelado de los combustibles vegetales en relación con sus respuestas al fuego.  Está escrito de una manera sencilla para que pueda ser interpretado por jefes de cuadrillas o de brigadas de combatientes de incendios forestales.  En el mismo de describe una metodología común y replicable para la obtención de los llamados "modelos de combustible".   Se dan ejemplos de 6 de estos modelos desarrollados para arbustales del ecotono bosque-estepa de la Patagonia. en base a información científica y empírica.Fil: Rey, Marcelo A.. Provincia de Río Negro. Servicio Provincial de Lucha contra Incendios Forestales; ArgentinaFil: Cuevas, Jorge. Provincia de Río Negro. Servicio Provincial de Lucha contra Incendios Forestales; ArgentinaFil: Sales, Bruno. Provincia de Río Negro. Servicio Provincial de Lucha contra Incendios Forestales; ArgentinaFil: Muñoz, Miriam M.. Provincia de Santa Cruz. Consejo Agrario; ArgentinaFil: Méndez, Mario. Provincia de Santa Cruz. Consejo Agrario; ArgentinaFil: Antequera, Silvio. Provincia de Chubut. Dirección General de Bosques y Parques; ArgentinaFil: Casas, Ángel Leandro. Provincia de Chubut. Dirección General de Bosques y Parques; ArgentinaFil: Lencinas, José Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Provincia del Chubut. Centro de Investigación y Extensión Forestal Andino Patagónico; ArgentinaFil: Mohr Bell, Diego Alejandro. Provincia del Chubut. Centro de Investigación y Extensión Forestal Andino Patagónico; ArgentinaFil: Gómez, Mariano. Provincia del Chubut. Centro de Investigación y Extensión Forestal Andino Patagónico; ArgentinaFil: Defossé, Guillermo Emilio. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Centro de Investigación y Extensión Forestal Andino Patagónico; Argentina. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ingeniería - Sede Esquel. Departamento de Ingeniería Forestal; ArgentinaFil: Bianchi, Lucas Osvaldo. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Rodríguez, Norberto. Universidad Nacional de la Patagonia "San Juan Bosco"; ArgentinaFil: Díaz, María Cecilia. Plan Nacional de Manejo del Fuego; ArgentinaFil: Dentoni, María del Carmen. Plan Nacional de Manejo del Fuego; ArgentinaFil: Zacconi, Gabriel. Plan Nacional de Manejo del Fuego; Argentin
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