2,895 research outputs found
Selection of native trees for intercropping with coffee in the Atlantic Rainforest biome
A challenge in establishing agroforestry systems is ensuring that farmers are interested in the tree species, and are aware of how to adequately manage these species. This challenge was tackled in the Atlantic Rainforest biome (Brazil), where a participatory trial with agroforestry coffee systems was carried out, followed by a participatory systematisation of the farmers experiences. Our objective was to identify the main tree species used by farmers as well as their criteria for selecting or rejecting tree species. Furthermore, we aimed to present a specific inventory of trees of the Leguminosae family. In order to collect the data, we reviewed the bibliography of the participatory trial, visited and interviewed the farmers and organised workshops with them. The main farmers' criteria for selecting tree species were compatibility with coffee, amount of biomass, production and the labour needed for tree management. The farmers listed 85 tree species; we recorded 28 tree species of the Leguminosae family. Most trees were either native to the biome or exotic fruit trees. In order to design and manage complex agroforestry systems, family farmers need sufficient knowledge and autonomy, which can be reinforced when a participatory methodology is used for developing on-farm agroforestry systems. In the case presented, the farmers learned how to manage, reclaim and conserve their land. The diversification of production, especially with fruit, contributes to food security and to a low cost/benefit ratio of agroforestry systems. The investigated agroforestry systems showed potential to restore the degraded landscape of the Atlantic Rainforest biome
Morphophysiological Plasticity Of Plagiotropic Branches In Response To Change In The Coffee Plant Spacing Within Rows
Changes in spacing within rows may alter the morphology of the coffee plant by affecting the physiological constituents of its productivity. Even though some common plant responses to crop spacing variation are known, there is yet no scientific evidence that elucidates the effects of decreased spacing on the sourcesink relation in plagiotropic branches and, its association with both productivity and eco-physiological aspects of coffee leaves, mainly for new coffee cultivars in the Brazilian savannah. The aim of this work was to characterize the morphophysiological responses of Coffea arabica L. cultivars subjected to different spacing between plants within rows. Four Arabica coffee cultivars (Catuaí Vermelho IAC 144, Catuaí Amarelo IAC 62, Catuaí Amarelo IAC 32, and Tupi RN IAC 1669-13) were transplanted in January 2010. A row spacing of 0.40, 0.50, 0.60, 0.70, and 0.80 m was adopted between plants, maintaining a 3.80-m constant between rows. A randomized block design with four replicates was applied. During the experimental period, several morphophysiological characteristics of plagiotropic fruiting branches were evaluated in the months of April and December in 2013 and, in April 2014. The evaluation was conducted based on two canopy positions; canopy toward the rows, representing low exposure to light or toward the inter-row spacing, representing high light exposure. Leaf gas exchange, chlorophyll fluorescence, and photosynthetic pigments levels were minimally or not at all affected by changing either the coffee cultivars or plant spacing. During the first evaluation, the leaf-to-fruitratio linearly increased, regardless of the cultivar. Light-exposed branches showed higher content of carotenoids and chlorophyll a in leaves and lower leaf-to-fruit-ratio as compared to those within the plant canopy. A major reduction in the number of fruits per branch was observed which was closely related to a parallel decrease in the number of fruits per node but not in the number of fruiting nodes per branch. Although this response was largely cultivar-dependent, it also changed according to the branch position in the hedgerow. Our results suggest that all tested cultivars exhibit high morphophysiological plasticity and have the potential to grow under different plant spacing within rows.3763819383
Infrastructure Assisted Data Dissemination for Vehicular Sensor Networks in Metropolitan Areas
Nuevas formas farmacéuticas para el tratamiento de enfermedades alérgicas
Specific immunotherapy involves certain drawbacks which could be minimized by the use of appropriate adjuvants, capable of amplifying the right immune response with minimal side effects. In this context, we review different types of immunotherapy vehicles and coadyuvants. We describe previous studies by our group in which we demonstrated the adjuvant capacity of Gantrez® AN nanoparticles, which can effectively enhance the immune response. We employed two types of nanoparticles (with and without LPS of Brucella ovis as immunomodulator) within capsulated ovoalbumin and Lollium perenne extract, tested on a model of mice sensitized to this allergenic mixture. In the challenge experiment involving the sensitized mice, differences in the mortality rate and in the MCP-1 levels were found between the treated groups and the control. Under the experimental conditions of this model of mice pre-sensitized to L. perenne, Gantrez®AN nanoparticles appeared to be a good strategy for immunotherapy. We finally tested these carriers administered by the oral route and found that they were able to protect a model of mice sensitized to ovalbumin from anaphylactic shock
Nanoparticulate adjuvants and delivery systems for allergen immunotherapy
In the last decades, significant progress in research and clinics has been made to offer possible innovative therapeutics for the management of allergic diseases. However, current allergen immunotherapy shows limitations concerning the long-term efficacy and safety due to local side effects and risk of anaphylaxis. Thus, effective and safe vaccines with reduced dose of allergen have been developed using adjuvants. Nevertheless, the use of adjuvants still has several disadvantages, which limits its use in human vaccines. In this context, several novel adjuvants for allergen immunotherapy are currently being investigated and developed. Currently, nanoparticles-based allergen-delivery systems have received much interest as potential adjuvants for allergen immunotherapy. It has been demonstrated that the incorporation of allergens into a delivery system plays an important role in the efficacy of allergy vaccines. Several nanoparticles-based delivery systems have been described, including biodegradable and nondegradable polymeric carriers. Therefore, this paper provides an overview of the current adjuvants used for allergen immunotherapy. Furthermore, nanoparticles-based allergen-delivery systems are focused as a novel and promising strategy for allergy vaccines
Incorporation Of Nanocrystals With Different Dimensionalities In Hybrid Tio2/p3ht Solar Cells
We investigate the effect of TiO2 nanoparticles-nanospheres and nanorods-inserted in the poly(3-hexylthiophene) (P3HT) matrix of TiO2?P3HT inverted hybrid solar cells. X-ray diffraction, high-resolution transmission electron microscopy, small-angle x-ray scattering, photoluminescence, and photoelectrochemical experiments were employed to investigate the structure, morphology, and photoactivity of TiO2 nanoparticles modified with 2-thiopheneacetic acid, mixed or not with P3HT. Both TiO2 nanospheres and TiO2 nanorods presented a good dispersion in the polymer matrix. The incorporation of TiO2 nanospheres and nanorods has improved the photocurrent generation, and devices with efficiency values up to 1.35% were obtained. Our results reveal that the nanoscale morphology enables an enhanced interfacial area for exciton dissociation. In particular, the nanospheres contribute with their high specific area, and the nanorods contribute with their high aspect ratio.51Lee, C.-K., Pao, C.-W., Chen, C.-W., Correlation of nanoscale organizations of polymer and nanocrystals in polymer/inorganic nanocrystal bulk heterojunction hybrid solar cells: Insights from multiscale molecular simulations (2013) Energy Environ. Sci., 6, pp. 307-315Huynh, W.U., Dittmer, J.J., Alivisatos, A.P., Hybrid nanorod: Polymer solar cells (2002) Science, 295, pp. 2425-2427Sian, S., Chen, C.-W., Polymer-metal-oxide hybrid solar cells (2013) J. Mater. Chem. A, 1, pp. 10574-10591Das, J., A facile nonaqueous route for fabricating titania nanorods and their viability in quasi-solid-state dye-sensitized solar cells (2010) J. Mater. Chem., 20, pp. 4425-4431Cozzoli, P.D., Kornowski, A., Weller, H., Low-temperature synthesis of soluble and processable organic-capped anatase TiO2 nanorods (2003) J. Am. Chem. Soc., 125, pp. 14539-14548Zeng, T.W., A large interconnecting network within hybrid MEH-PPV/TiO2 nanorod photovoltaic devices (2006) Nanotechnology, 17, p. 5387Yang, P., TiO2 nanowire electron transport pathways inside organic photovoltaics (2013) Phys. Chem. Chem. Phys., 15, pp. 4566-4572Lin, Y., Morphology control in TiO2 nanorod/polythiophene composites for bulk heterojunction solar cells using hydrogen bonding (2012) Macromolecules, 45, pp. 8665-8673Ranjitha, A., Inverted organic solar cells based on Cd-doped TiO2 as an electron extraction layer (2014) Superlattices Microstruct., 74, pp. 114-122Bolognesi, M., The effect of selective contact electrodes on the interfacial charge recombination kinetics and device efficiency of organic polymer solar cells (2011) Phys. Chem. Chem. Phys., 13, pp. 6105-6109Mor, G.K., High efficiency double heterojunction polymer photovoltaic cells using highly ordered TiO2 nanotube arrays (2007) Appl. Phys. Lett., 91, p. 152111Planells, M., Oligothiophene interlayer effect on photocurrent generation for hybrid TiO2/P3HT solar cells (2014) Appl. Mater. Interfaces, 6, pp. 17226-17235Freitas, F.S., Tailoring the interface using thiophene small molecules in TiO2/P3HT hybrid solar cells (2012) Phys. Chem. Chem. Phys., 14, pp. 11990-11993Liu, K., Efficient hybrid plasmonic polymer solar cells with Ag nanoparticle decorated TiO2 nanorods embedded in the active layer (2014) Nanoscale, 6, pp. 6180-6186Lin, Y.-Y., Interfacial nanostructuring on the performance of polymer/TiO2 nanorod bulk heterojunction solar cells (2009) J. Am. Chem. Soc., 131, pp. 3644-3649Eom, S.H., Roles of interfacial modifiers in hybrid solar cells: Inorganic/polymer bilayer versus inorganic/polymer: Fullerene bulk heterojunction (2014) Appl. Mater. 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Biochemical, genetic and zoosporicidal properties of cyclic lipopeptide surfactants produced by Pseudomonas fluorescens
Zoospores play an important role in the infection of plant and animal hosts by oomycetes and other zoosporic fungi. In this study, six fluorescent Pseudomonas isolates with zoosporicidal activities were obtained from the wheat rhizosphere. Zoospores of multiple oomycetes, including Pythium species, Albugo candida, and Phytophthora infestans, were rendered immotile within 30 s of exposure to cell suspensions or cell culture supernatants of the six isolates, and subsequent lysis occurred within 60 s. The representative strain SS101, identified as Pseudomonas fluorescens biovar II, reduced the surface tension of water from 73 to 30 mN m-1. The application of cell suspensions of strain SS101 to soil or hyacinth bulbs provided significant protection against root rot caused by Pythium intermedium. Five Tn5 mutants of strain SS101lacked the abilities to reduce the surface tension of water and to cause lysis of zoospores. Genetic characterization of two surfactant-deficient mutants showed that the transposons had integrated into condensation domains of peptide synthetases. A partially purified extract from strain SS101 reduced the surface tension of water to 30 mN m-1 and reached the critical micelle concentration at 25 micrograms ml-1. Reverse-phase high-performance liquid chromatography yielded eight different fractions, five of which had surface activity and caused lysis of zoospores. Mass spectrometry and nuclear magnetic resonance analyses allowed the identification of the main constituent as a cyclic lipopeptide (1,139 Da) containing nine amino acids and a 10-carbon hydroxy fatty acid. The other four zoosporicidal fractions were closely related to the main constituent, with molecular massesranging from 1,111 to 1,169 Da
The flavonoid agathisflavone modulates the microglial neuroinflammatory response and enhances remyelination
Myelin loss is the hallmark of the demyelinating disease multiple sclerosis (MS) and plays a significant role in multiple neurodegenerative diseases. A common factor in all neuropathologies is the central role of microglia, the intrinsic immune cells of the central nervous system (CNS). Microglia are activated in pathology and can have both pro- and anti-inflammatory functions. Here, we examined the effects of the flavonoid agathisflavone on microglia and remyelination in the cerebellar slice model following lysolecithin induced demyelination. Notably, agathisflavone enhances remyelination and alters microglial activation state, as determined by their morphology and cytokine profile. Furthermore, these effects of agathisflavone on remyelination and microglial activation were inhibited by blockade of estrogen receptor α. Thus, our results identify agathisflavone as a novel compound that may act via ER to regulate microglial activation and enhance remyelination and repair
Be Stars: Rapidly Rotating Pulsators
I will show that Be stars are, without exception, a class of rapidly rotating
stars, which are in the majority of cases pulsating stars as well, while none
of them does possess a large scale (i.e. with significant dipolar contribution)
magnetic field.Comment: Review talk given at "XX Stellar Pulsation Conference Series: Impact
of new instrumentation and new insights in stellar pulsations", Granada, 5-9
September 2011, in press in AIP Conf. Se
In vivo assessment of possible probiotic properties of Zymomonas mobilis in a Wistar rat model
In recent years the incorporation of probiotic bacteria into foods has
received increasing scientific interest for health promotion and
disease prevention. The safety and probiotic properties of Zymomonas
mobilis CP4 (UFPEDA-202) was studied in a Wistar rat model fed the
109 colony forming units (cfu)/mL-1 of the assayed strain for 30 days.
No abnormal clinical signs were noted in the group receiving viable
cells of Z. mobilis and water (control) during the period of the
experiment. There were no significant difference (p > 0.05) in feed
intake and weight gain among mice fed the Z. mobilis in comparison to
the control group. No bacteria were found in blood, liver and spleen of
any animals. Mice receiving Z. mobilis showed significantly differences
(p < 0.05) in total and differential leucocytes count, excepting for
neutrophils, after the experimental period. Otherwise, it was not found
in control group. Histological examination showed that feeding mice
with Z. mobilis caused no signs of adverse effects on gut, liver and
spleen. From these results, Z. mobilis CP4 (UFEPEDA-202) is likely to
be nonpathogenic and safe for consumption, and could have a slight
modulating effect on immunological performance in mice
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