Learning by doing: a participatory methodology for systematization of experiments with agroforestry systems, with an example of its application     

Helton Nonato de Souza  Irene Maria Cardoso  Eduardo de Sá Mendon?a  An?r Fiorini Carvalho  Gustavo Bediaga de Oliveira  Davi Feital Gjorup  Ver?nica Rocha Bonfim 《Agroforestry Systems》2012,85(2):247-262

Participatory research methods have helped scientists to understand how farmers experiment and to seek partnerships with farmers in developing technologies with enhanced relevance and adoption. This paper reports on the development of a participatory methodology to systematize long-term experimentation with agroforestry systems carried out in a hotspot of biodiversity by non-governmental organizations and local farmers. A methodological guide for systematization and techniques used for Participatory Rural Appraisal formed the basis of our work. We propose an analytical framework that recognizes systems of reflexive and learning interactions, in order to make the learned lessons explicit. At the process level, the main lessons and recommendations are as follows. It is important to establish partnerships to conduct innovative and complex experimentation with agroforest. Participatory systematization allows us to improve the methodological aspects of design, implementation and management of on-farm participatory experimentation. It also serves to synthesize the main findings and to extract lessons from agroforestry systems experiments. It fosters the technical improvement of agroforestry systems. It creates possibilities for reflection on agroforestry systems by farmers, extensionists and researchers, as well as their learning with respect to management of such systems. The findings are placed in the context of current theory on participatory experimentation in agriculture. Extractive and interactive approaches help to produce rich insights of mutual interest through collaboration by identifying local, regional and global convergences, complementarities, and conflicts of interest; which affect the advance of new eco-friendly technologies, to both improve the livelihoods and to reverse biodiversity loss and environmental degradation.  相似文献   

Extracellular matrix alterations in experimental Leishmania amazonensis infection in susceptible and resistant mice     

Silva-Almeida M  Carvalho LO  Abreu-Silva AL  Souza CS  Hardoim DJ  Calabrese KS 《Veterinary research》2012,43(1):10

ABSTRACT: Leishmania is inoculated, by the bite of an infected sandfly, into the skin of the host, where the promastigotes are phagocyted by dermal macrophages. The dermal region comprises cells and abundant extracellular matrix. Studies show that matrix metalloproteinases play an important role in host defense responses against pathogens in mammals and that their activities lead to the production of antimicrobial peptides. The aim of this study is to evaluate the changes in the distribution of fibronectin and laminin as well as in the elastic system fibres during the course of infection caused by Leishmania amazonensis in mice with distinct genetic backgrounds of susceptibility to this parasite. The results showed that BALB/c presented an enhancement of fibronectin during the course of infection when compared to their control group while the infected or non-infected C3H.He showed a decrease of this protein at end of the experiment. Laminin, on the other hand, remained unaltered in both strains. Also in both BALB/c and C3H.He mice the elastic and elaunin fibres remained unchanged while the oxytalan fibres decreased along the experiment. Ninety days after the infection C3H.He mice had recovered their capacity to produce oxytalan fibres.  相似文献   

Hematological and coagulation profiles in dogs experimentally infected with Angiostrongylus vasorum (Baillet, 1866).     

Marcia C Cury  W S Lima  M P Guimar?es  M G Carvalho 《Veterinary parasitology》2002,104(2):139-149

Hematological and coagulation profiles were studied in crossbred dogs experimentally infected with Angiostrongylus vasorum. Two groups of five dogs were experimentally inoculated with 50 and 100 third stage infective larvae (L(3)) of A. vasorum per kilogram of body weight. A third group of five uninfected animals was used as control. One sample of 10 ml of blood was collected from each animal on the 10, 20, 30, and 45 days after inoculation (dai) and at 30-day intervals thereafter for the remainder of the 210-day experimental period. The blood sample was used for the complete hemogram and platelet count, as well as measurements of prothrombin time, partial thromboplastin time and factors V and VIII. Anemia was observed in infected dogs, 6 weeks after the infection. The eosinophils presented peaks in four periods after infection. Thrombocytopenia became accentuated on the 72 dai. Decreased prothrombin time activity and increased partial thromboplastin time were observed at the 6 and 9 weeks after infection and decreased of factors VIII and V activities occurred from 4 to 6 weeks after infection. It may be conclude that infection by A. vasorum in dogs may cause a discrete anemia during the acute phase which is probably regenerative. In addition, important hemostatic alterations due to the infection suggest a chronic intravascular consumption coagulopathy.  相似文献   

Determination of melamine content in amino resins by near-infrared spectroscopy     

Ana Henriques  Paulo Cruz  João M. Ferra  Jorge Martins  Fernão D. Magalhães  Luísa H. Carvalho 《Wood Science and Technology》2013,47(5):939-948

Melamine-urea-formaldehyde resin production has increased in the last years due to low formaldehyde emissions and improved moisture resistance when applied on wood-based panels. Melamine is a relatively high-cost raw material in the resin formulation and has a significant effect on wood-based panel properties. It is important for industry to implement efficient quality control methods to determine melamine content in resins. The main objective of this work was to develop chemometric techniques for off-line monitoring of melamine content using near-infrared spectroscopy. The use of interval partial least squares regression allowed identifying the most interesting spectral ranges for analysis (4,400–4,800 and 5,200–5,600 cm^?1) and the best preprocessing methods to use in the determination of this property. When the appropriate spectral range and preprocessing methods are selected, it is possible to obtain calibration models with high correlation coefficients.  相似文献   

Benign intraocular teratoid medulloepithelioma causing glaucoma in an 11‐year‐old Arabian mare     

Marta Leiva  Fiorenza Felici  Andrea Carvalho  Antonio Ramis  Teresa Peña 《Veterinary ophthalmology》2013,16(4):297-302

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Divergence between hepatic insulin-like growth factor (IGF)-I mRNA expression and IGF-I serum levels in Leishmania (Leishmania) infantum chagasi-infected dogs     

Flaviane A. Pinho  Nilton A. Magalhães  Kleverton R. Silva  Aline A. Carvalho  Fernando L.L. Oliveira  Eduardo M. Ramos-Sanchez  Hiro Goto  Francisco A.L. Costa 《Veterinary immunology and immunopathology》2013,151(1-2):163-167

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Evaluation of Praziquantel effects on Echinostoma paraensei ultrastructure     

Júlia P. Gonçalves  Aleksandra Oliveira-Menezes  Arnaldo Maldonado Junior  Técia M.U. Carvalho  Wanderley de Souza 《Veterinary parasitology》2013

Echinostomiasis is a food-borne, intestinal, zoonotic, snail-mediated helminthiasis caused by digenean trematodes of the family Echinostomatidae with seven species of the genus Echinostoma infecting humans or domestic and wildlife animals. Echinostoma paraensei is a peristomic 37-collar-spined echinostome belonging to the “revolutum group”.  相似文献   

Sward structure management for a maximum short‐term intake rate in annual ryegrass     

M. F. Amaral  J. C. Mezzalira  C. Bremm  J. K. Da Trindade  M. J. Gibb  R. W. M. Suñe  P. C. de F. Carvalho 《Grass and Forage Science》2013,68(2):271-277

This study tested the hypothesis that different sward structures, which were constructed by varying the pre‐ and post‐grazing sward heights of annual ryegrass pasture (Lolium multiflorum Lam.) in southern Brazil, affect the short‐term intake rate (STIR) by dairy cows. Treatments consisted of four sward‐management strategies defined by a combination of two pre‐ (25 and 15 cm) and two post‐grazing sward heights (10 and 5 cm): 15‐05, 15‐10, 25‐05 and 25‐10. A completely randomized block design with four replicates was used for the experimental design. The STIR was determined by the double‐weighing technique. Jaw movements were evaluated using automatic recorders (IGER Behaviour Recorder). The results showed that treatment 25‐10 allowed the animals to collect more herbage with a greater bite mass and thus resulted in a greater STIR. Treatments in which sward height was reduced to 10 cm generally favoured the ingestion process than treatments with a post‐grazing sward height of 5 cm.  相似文献   

Spasmolytic Effect of Caulerpine Involves Blockade of Ca2+ Influx on Guinea Pig Ileum     

Luiz Henrique Agra Cavalcante-Silva  Ana Carolina de Carvalho Correia  José Maria Barbosa-Filho  Bagnólia Araújo da Silva  Bárbara Viviana de Oliveira Santos  Daysianne Pereira de Lira  Jéssica Celestino Ferreira Sousa  George Emmanuel C. de Miranda  Fabiana de Andrade Cavalcante  Magna Suzana Alexandre-Moreira 《Marine drugs》2013,11(5):1553-1564

In this work, we investigated the spasmolytic effect of caulerpine, a bisindole alkaloid isolated from marine algae of the Caulerpa genus, on guinea pig ileum. Our findings indicated that caulerpine inhibited phasic contractions induced by carbachol (IC₅₀ = 7.0 ± 1.9 × 10⁻⁵ M), histamine (IC₅₀ = 1.3 ± 0.3 × 10⁻⁴ M) and serotonin (IC₅₀ = 8.0 ± 1.4 × 10⁻⁵ M) in a non-selective manner. Furthermore, caulerpine concentration-dependently inhibited serotonin-induced cumulative contractions (pD′₂ = 4.48 ± 0.08), shifting the curves to the right with E_max reduction and slope of 2.44 ± 0.21, suggesting a noncompetitive antagonism pseudo-irreversible. The alkaloid also relaxed the ileum pre-contracted by KCl (EC₅₀ = 9.0 ± 0.9 × 10⁻⁵ M) and carbachol (EC₅₀ = 4.6 ± 0.7 × 10⁻⁵ M) in a concentration-dependent manner. This effect was probably due to inhibition of Ca²⁺ influx through voltage-gated calcium channels (Ca_V), since caulerpine slightly inhibited the CaCl₂-induced contractions in depolarizing medium without Ca²⁺, shifting the curves to the right and with E_max reduction. According to these results, the spasmolytic effect of caulerpine on guinea pig ileum seems to involve inhibition of Ca²⁺ influx through Ca_V. However, other mechanisms are not discarded.  相似文献   

Increase in Cardiac Troponin I in a Lamb with Tetralogy of Fallot     

Elisa Barp NEUWALD  Frederico Aécio Carvalho SOARES  Cristina Terres DREYER  Samuel CARNESELLA  Angelica Terezinha Barth WOUTERS  Félix Hilario Diaz GONZáLEZ  David DRIEMEIER 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2013,75(10):1371-1373

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