3,009 research outputs found

    Photocontrol of productivity and stem elongation of three Rosa x hybrida L. cultivars under photoselective films

    Get PDF
    Se evaluaron los cambios en la radiación transmitida a través de films fotoselectivos (FS) fluorescentes y el impacto de estos cambios sobre la producción de tres cultivares de rosa para corte Fuego Negro, Maroussia y Anna. Se observó que los FS nuevos o expuestos a la radiación solar vs. noFS disminuyen la transmisión de radiación azul (A) (-28,4 a -32,9%, respectivamente), incrementan el R produciendo una relación R:RL mayor (+3,6%), si bien transmiten algo menos de radiación fotosintéticamente activa que los noFS nuevos. El número de rosas producidas fue significativamente mayor bajo el FS vs. noFS en los tres cv (+24, +32 y +36% en Anna, Fuego Negro y Maroussia, respectivamente), con un peso fresco y seco (PF y PS) significativamente mayor y tallos florales más largos en Anna y Maroussia (50,69 y 43,91 cm vs. 38,91 y 40,04 cm en invierno y primavera, respectivamente), y pimpollos significativamente más largos y de mayor PF y PS en los tres cv. Mayor relación R:RL y menor UV-A y A en la radiación transmitida por films FS aumentaron la cantidad y calidad de determinados cultivares de rosas mostrando una alternativa a los reguladores químicos de crecimiento.This research evaluate changes in the radiation transmitted through a photoselective, fluorescent polyethylene film (PS), and the impact of these changes on the production of three cut rose cultivars, Fuego Negro, Maroussia and Anna. PS vs. nonPS films, new or exposed to solar radiation, decreased transmission of blue radiation (-28.4 to -32.9%, PS-new and PS-old, respectively), increased red radiation, resulting in a R:FR ratio greater 3.6% than for nonPS, although, PS-new and PS-old films transmitted a smaller percentage of PAR than non-PS-new (-16.6 and -22.4%, respectively). The number of roses harvested was significantly higher under PS vs. nonPS film for the three cultivars (+24, +32 and +36% flowers m-2, in Anna, Fuego Negro and Maroussia, respectively), with significantly higher fresh weight (FW) and dry weight (DW), longer floral stems in Anna and Maroussia (50.69 and 43.91 cm vs. 38.91 and 40.04 in winter and spring, respectively) and buds significantly longer and higher FW and DW in the three cv. Higher R:FR and lower UV-A and B radiation of PS greenhouse covers increased quantity and quality of some of these rose cultivars featuring an alternative to chemical growth regulators.Fil: Mascarini, Libertad. Universidad de Buenos Aires. Facultad de AgronomíaFil: Lorenzo, Gabriel A.. Universidad de Buenos Aires. Facultad de AgronomíaFil: Burgos, Marcelo L.. Universidad de Buenos Aires. Facultad de Agronomí

    NGC 6309, a Planetary Nebula that Shifted from Round to Multipolar

    Full text link
    We present new narrow-band Ha, [N II], and [O III] high-resolution images of the quadrupolar planetary nebula (PN) NGC 6309 that show in great detail its bipolar lobes and reveal new morphological features. New high- and low-dispersion long-slit spectra have been obtained to help in the investigation of the new nebular components. The images and spectra unveil two diffuse blobs, one of them located at 55 arcsec from the central star along the NE direction (PA= +71) and the other at 78 arcsec in the SW direction (PA= -151). Therefore, these structures do not share the symmetry axes of the inner bipolar outflows. Their radial velocities relative to the system are quite low: +3 and -4 km/s, respectively. Spectroscopic data confirm a high [O III] to Ha ratio, indicating that the blobs are being excited by the UV flux from the central star. Our images convincingly show a spherical halo 60 arcsec in diameter encircling the quadrupolar nebula. The expansion velocity of this shell is low, 66 km/s. The software SHAPE has been used to construct a morpho-kinematic model for the ring and the bipolar flows that implies an age of 4,000 yrs, the expansion of the halo sets a lower limit for its age 46,000 yrs, and the very low expansion of the blobs suggests they are part of a large structure corresponding to a mass ejection that took place 150,000 yrs ago. In NGC 6309 we have direct evidence of a change in the geometry of mass-loss, from spherical in the halo to axially-symmetric in the two pairs of bipolar lobes.Comment: 8 pages, 7 figures, Accepted for publication in MNRA

    Organic farming enhances parasitoid diversity at the local and landscape scales

    Get PDF
    1. The magnitude of the benefits derived from organic farming within contrasting managed landscapes remains unclear and, in particular, the potential scale-dependent response of insect parasitoids is relatively unexplored. Identifying the scale at which parasitoids are affected by organic farming will be an important step to enhance their conservation. 2. We sampled tachinid parasitoids at the centre and margin of arable and grassland fields on paired organic and conventional farms located in landscapes with different proportions of organic land. A total of 192 fields were sampled in two biogeographical regions of the UK. 3. We found that the positive effect of organic farming on tachinid parasitoid diversity can be observed at multiple spatial scales. At the local scale, we found higher abundance and species richness of tachinid parasitoids on organic than on conventional farms and on field margins than on field centres. At the landscape scale, the diversity of tachinids was higher in landscapes with higher proportions of organic land. At both scales, the positive effect of organic farming was clear for arable fields, while it was almost neutral for grasslands. 4. Synthesis and applications. Any attempt to enhance parasitoid diversity in agricultural landscapes needs to consider the local management in relation to the habitat type, location within the field and agricultural management in the surrounding landscape. To restore parasitoid diversity, the promotion of organic agriculture should aim to increase both the total extent of organic farming and the connectivity of individual farms. As the benefits of organic farming to biodiversity clearly spread beyond individual farm boundaries, any assessment of organic farming should consider these positive externalities

    Energy Insecurity and Management of Strategic Natural Resources: Analysis of Argentina´s Biofuel Policy in the Global Context

    Get PDF
    La pregunta que motiva el análisis es si las políticas sobre biocombustibles en Argentina, responden a sus problemas de seguridad energética. A modo de contexto, realizamos un análisis internacional y otro nacional. En el primer caso, se realiza un diagnóstico del flujo de recursos energéticos (hidrocarburos), crecimiento económico de las principales potencias, la volatilidad del precio, y la relación de este último con los conflictos internacionales. En este marco, se hace especial referencia a EE.UU., la Unión Europea y Brasil. En el segundo caso, identificamos la relevancia de intereses sectoriales, actores intervinientes y políticas públicas. En esta parte, el análisis incluye las consecuencias de la explotación de los recursos naturales.   En ambos niveles, identificamos 3 categorías temporales: estructura, coyuntura y acontecimiento. En segundo lugar, abordamos la variable “inseguridad energética”, la cual adquiere diferentes valores, representativos de la situación energética (que puede ser de crisis o seguridad en sus valores extremos).  Por último, se compone la variable “recursos naturales estratégicos”, de tipo dependiente, en tanto los recursos son explotados en función de las necesidades energéticas. Todas estas herramientas teórico – conceptuales referidas son utilizadas para estudiar el tema biocombustibles en Argentina desde las relaciones internacionales.Our guide question on this paper is: does Argentina’s biofuel policy mean a solution to its energy security problem? Regarding this, firstly, we considered an analysis based in both international and national contexts. We included a description of several factors as the flow of international energetic resources (oil), the rise of developing countries, price volatility and its relation to international conflicts. Under this framework, we emphasized in the international context the cases of the United States, the European Union and Brazil. Additionally, we identified in a national context, the relevance of sectorial interests, the actors involved, inner policy and we included the exploitation of natural resources ant its consequences. In both levels, we first identified 3 categories framed in a temporal dimension: structure, circumstances and events. Secondly, we considered conceptually an “energy insecurity” dimension to describe possible sequences of an energy context (from crisis to a situation of full security as possible extremes). Finally, we focused on the “strategic natural.Fil: De Paula, Gabriel. Estado Mayor Conjunto de Las Fuerzas Armadas.; Argentina. Universidad del Salvador; ArgentinaFil: Lorenzo, Cristian A.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; Argentin

    Fotocontrol de la productividad y elongación de tallos de tres cultivares de Rosa x hybrida L. bajo cubiertas de polietileno fotoselectivas

    Get PDF
    This research evaluate changes in the radiation transmitted through a photoselective, fluorescent polyethylene film (PS), and the impact of these changes on the production of three cut rose cultivars, Fuego Negro, Maroussia and Anna. PS vs. nonPS films, new or exposed to solar radiation, decreased transmission of blue radiation (-28.4 to -32.9%, PS-new and PS-old, respectively), increased red radiation, resulting in a R:FR ratio greater 3.6% than for nonPS, although, PS-new and PS-old films transmitted a smaller percentage of PAR than non-PS-new (-16.6 and -22.4%, respectively). The number of roses harvested was significantly higher under PS vs. nonPS film for the three cultivars (+24, +32 and +36% flowers m-2, in Anna, Fuego Negro and Maroussia, respectively), with significantly higher fresh weight (FW) and dry weight (DW), longer floral stems in Anna and Maroussia (50.69 and 43.91 cm vs. 38.91 and 40.04 in winter and spring, respectively) and buds significantly longer and higher FW and DW in the three cv. Higher R:FR and lower UV-A and B radiation of PS greenhouse covers increased quantity and quality of some of these rose cultivars featuring an alternative to chemical growth regulators.Se evaluaron los cambios en la radiación transmitida a través de films fotoselectivos (FS) fluorescentes y el impacto de estos cambios sobre la producción de tres cultivares de rosa para corte Fuego Negro, Maroussia y Anna. Se observó que los FS nuevos o expuestos a la radiación solar vs. noFS disminuyen la transmisión de radiación azul (A) (-28,4 a -32,9%, respectivamente), incrementan el R produciendo una relación R:RL mayor (+3,6%), si bien transmiten algo menos de radiación fotosintéticamente activa que los noFS nuevos. El número de rosas producidas fue significativamente mayor bajo el FS vs. noFS en los tres cv (+24, +32 y +36% en Anna, Fuego Negro y Maroussia, respectivamente), con un peso fresco y seco (PF y PS) significativamente mayor y tallos florales más largos en Anna y Maroussia (50,69 y 43,91 cm vs. 38,91 y 40,04 cm en invierno y primavera, respectivamente), y pimpollos significativamente más largos y de mayor PF y PS en los tres cv. Mayor relación R:RL y menor UV-A y A en la radiación transmitida por films FS aumentaron la cantidad y calidad de determinados cultivares de rosas mostrando una alternativa a los reguladores químicos de crecimiento

    Benefits of Massage-Myofascial Release Therapy on Pain, Anxiety, Quality of Sleep, Depression, and Quality of Life in Patients with Fibromyalgia

    Get PDF
    Fibromyalgia is a chronic syndrome characterized by generalized pain, joint rigidity, intense fatigue, sleep alterations, headache, spastic colon, craniomandibular dysfunction, anxiety, and depression. The purpose of the present study was to determine whether massage-myofascial release therapy can improve pain, anxiety, quality of sleep, depression, and quality of life in patients with fibromyalgia. A randomized controlled clinical trial was performed. Seventy-four fibromyalgia patients were randomly assigned to experimental (massage-myofascial release therapy) and placebo (sham treatment with disconnected magnotherapy device) groups. The intervention period was 20 weeks. Pain, anxiety, quality of sleep, depression, and quality of life were determined at baseline, after the last treatment session, and at 1 month and 6 months. Immediately after treatment and at 1 month, anxiety levels, quality of sleep, pain, and quality of life were improved in the experimental group over the placebo group. However, at 6 months postintervention, there were only significant differences in the quality of sleep index. Myofascial release techniques improved pain and quality of life in patients with fibromyalgia

    Stochastic Simulation of Process Calculi for Biology

    Full text link
    Biological systems typically involve large numbers of components with complex, highly parallel interactions and intrinsic stochasticity. To model this complexity, numerous programming languages based on process calculi have been developed, many of which are expressive enough to generate unbounded numbers of molecular species and reactions. As a result of this expressiveness, such calculi cannot rely on standard reaction-based simulation methods, which require fixed numbers of species and reactions. Rather than implementing custom stochastic simulation algorithms for each process calculus, we propose to use a generic abstract machine that can be instantiated to a range of process calculi and a range of reaction-based simulation algorithms. The abstract machine functions as a just-in-time compiler, which dynamically updates the set of possible reactions and chooses the next reaction in an iterative cycle. In this short paper we give a brief summary of the generic abstract machine, and show how it can be instantiated with the stochastic simulation algorithm known as Gillespie's Direct Method. We also discuss the wider implications of such an abstract machine, and outline how it can be used to simulate multiple calculi simultaneously within a common framework.Comment: In Proceedings MeCBIC 2010, arXiv:1011.005

    Haemoglobin levels for population from Gambo, a rural area of Ethiopia, and their association with anaemia and malaria

    Get PDF
    BACKGROUND: Knowledge of appropriate reference intervals is critical not only to provide optimal clinical care, but also to enrol populations in medical research. The aim of this study was to generate normal ranges of laboratory values for haemoglobin among healthy Ethiopian adults and children and to determine if anaemia is a possible indicator of malaria in women and children in this area of Ethiopia. METHODS: This study was carried out from January 2008 to May 2010. The reference sample population with malaria-negative consisted of 454 individuals, divided women, men and children. The malaria-infected sample population consisted of 117 individuals. The reference ranges were based on the guidelines from the Clinical and Laboratory Standards Institute. Haemoglobin concentration was determined by Hemo-Control EKF Diagnostic Analyser on whole blood. Testing for malaria-positive and negative infection was done by microscopy and by PCR. RESULTS: The lower limits for adult haemoglobin range obtained from this population were slightly higher than those derived from other African populations, but were equal to those established by other studies in Ethiopia and the World Health Organization (WHO). Regarding children, the minimum values were lower than those obtained from different African populations and those established by WHO. The malaria-negative group had anaemia in 35.6% of cases and in the malaria-positive group in 70.9%. There was a stronger, statistically significant association between anaemia and malaria-positive samples than between anaemia and malaria-negative samples in women and both groups of children. CONCLUSIONS: The results from this study are a contribution in the definition of the haemoglobin parameters in African populations, which could be taken as standards for interpretation of laboratory results. The haemoglobin indices in adults from Gambo tended to be higher than other African populations and in children were lower than other studies in Africa. The results also suggest that anaemia is not useful as a supportive diagnostic criterion to monitor and evaluate malaria in women and children from Ethiopia, because a 29.1% of malaria cases will be not detected, because of not having anaemia

    Design and methodology of a cluster-randomized trial in early care and education centers to meet physical activity guidelines: Sustainability via Active Garden Education (SAGE)

    Get PDF
    Strategies are needed to help early care and education centers (ECEC) comply with policies to meet daily physical activity and fruit and vegetable guidelines for young children. This manuscript describes the design and methodology of Sustainability via Active Garden Education (SAGE), a 12-session cluster-randomized controlled crossover design trial using community-based participatory research (CBPR) to test a garden-based ECEC physical activity and fruit and vegetables promotion intervention for young children aged 3–5 years in 20 sites. The SAGE curriculum uses the plant lifecycle as a metaphor for human development. Children learn how to plant, water, weed, harvest, and do simple food preparation involving washing, cleaning, and sampling fruit and vegetables along with active learning songs, games, science experiments, mindful eating exercises, and interactive discussions to reinforce various healthy lifestyle topics. Parents will receive newsletters and text messages linked to the curriculum, describing local resources and events, and to remind them about activities and assessments. Children will be measured on physical activity, height, and weight and observed during meal and snack times to document dietary habits. Parents will complete measures about dietary habits outside of the ECEC, parenting practices, home physical activity resources, and home fruit and vegetable availability. SAGE fills an important void in the policy literature by employing a participatory strategy to produce a carefully crafted and engaging curriculum with the goal of meeting health policy guidelines and educational accreditation standards. If successful, SAGE may inform and inspire widespread dissemination and implementation to reduce health disparities and improve health equity
    corecore