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1.
Acta amaz ; 48(3): 179-190, July-Sept. 2018. ilus, map, tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1455369

RESUMO

This paper presents a novel approach for estimating the height of individual trees in secondary forests at two study sites: Manaus (central Amazon) and Santarém (eastern Amazon) in the Brazilian Amazon region. The approach consists of adjusting tree height-diameter at breast height (H:DBH) models in each study site by ecological species groups: pioneers, early secondary, and late secondary. Overall, the DBH and corresponding height (H) of 1,178 individual trees were measured during two field campaigns: August 2014 in Manaus and September 2015 in Santarém. We tested the five most commonly used log-linear and nonlinear H:DBH models, as determined by the available literature. The hyperbolic model: H = a.DBH/(b+DBH) was found to present the best fit when evaluated using validation data. Significant differences in the fitted parameters were found between pioneer and secondary species from Manaus and Santarém by F-test, meaning that site-specific and also ecological-group H:DBH models should be used to more accurately predict H as a function of DBH. This novel approach provides specific equations to estimate height of secondary forest trees for particular sites and ecological species groups. The presented set of equations will allow better biomass and carbon stock estimates in secondary forests of the Brazilian Amazon.


Este trabalho apresenta uma nova abordagem para a estimativa de altura de árvores em florestas secundárias em duas áreas de estudo na Amazônia brasileira: Manaus (Amazônia central) e Santarém (Amazônia oriental). A abordagem consistiu em ajustar modelos hipsométricos separados por área de estudo e grupos ecológicos de espécies: pioneiras, secundárias iniciais e secundárias tardias. No total, 1178 árvores foram medidas em diâmetro e altura em duas etapas de campo: agosto de 2014 em Manaus e Setembro de 2015 em Santarém. Foram testados cinco modelos log-lineares e não lineares mais utilizados na literatura. O modelo hiperbólico: H = a.D/(b+D) foi o que apresentou o melhor ajuste quando avaliado com os dados de validação. Diferenças significativas nos parâmetros de ajuste foram observadas entre as espécies pioneiras e secundárias de Manaus e Santarém pelo teste F, significando que equações específicas por grupos ecológicos e área de estudo deveriam ser utilizadas para estimar a altura (H) a partir do diâmetro (D) com maior acurácia. Esta nova abordagem fornece equações específicas para localidade e grupo ecológico, para estimar a altura das árvores em florestas secundárias. O conjunto de equações desenvolvidas permitirá melhorar as estimativas de biomassa e a quantificação dos estoques de carbono nas florestas secundárias da Amazônia brasileira.


Assuntos
Biometria/métodos , Estatística como Assunto , Árvores/anatomia & histologia , Dinâmica não Linear , Modelos Lineares
2.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1537001

RESUMO

Los sistemas de uso del suelo con leñosas perennes, como cacaotales, mitigan el cambio climático, al capturar CO2 atmosférico. El objetivo del estudio fue estimar la fijación de carbono en biomasa total en los sistemas de producción de cacao, dominantes del Tolima, Colombia. El estudio, se realizó en Rovira y Falan, empleando un diseño experimental, completamente al azar, con seis sistemas de producción de cacao: monocultivo, sistema agroforestal (SAF) con maderables, SAF con aguacate, SAF con cítricos, SAF con frutales, y SAF con maderables y frutales y tres repeticiones. Se establecieron dos parcelas de muestreo rectangulares, de 1.000m² por unidad de muestreo, donde se identificaron y midieron los árboles con dap ≥ 10cm (diámetro del tronco a la altura del pecho -dap- y altura total -ht). Se establecieron dos sub-parcelas de 256m², por parcela principal, para medir arbustos de cacao: ht y diámetro del tronco, a 30 cm de altura (D30). Se emplearon modelos alométricos, para estimar la biomasa. El SAF con maderables y frutales y SAF con frutales presentaron la mayor biomasa total (122,0 y 72,5t/ ha). En el SAF con maderables y frutales, se evidenció el mayor almacenamiento de carbono, con 61,0t C/ha, mientras que la mayor tasa de fijación de carbono fue de 17,7t/ha/ año, para el SAF con cítricos. Los resultados sugieren que la producción de cacao, que incluyen otras especies vegetales, diversifica la producción e incrementa la seguridad alimentaria y la generación de servicios ambientales, tal como la captura de carbono atmosférico.


The land use systems with woody perennials species, such as cacao plantations, mitigate climate change by capturing atmospheric CO2. The aim of the study was to estimate the fixation of atmospheric carbon in total biomass in the most dominant cocoa production systems in Tolima, Colombia. The study was carried out in Rovira and Falan using a completely randomized experimental design with six cocoa production systems: monoculture, agroforestry system (SAF) with timber trees, SAF with avocado, SAF with citrus species, SAF with fruit trees and SAF with timber and fruit species with three replications. Two rectangular sampling plots 1000m² were established by sampling unit where trees with diameter of trunk at breast height (dbh) ≥ 10cm were identified and measured (dbh and total height - th). Two subplots of 256 m² by main plot, for measuring cocoa bushes were established: ht and trunk diameter at 30cm height (D30). Allometric models to estimate biomass were used. The AFS with timber and fruit species and AFS with fruit species had the greatest biomass (122.0 and 72.5t/ha). In the AFS with timber and fruit species presented the highest carbon storage in biomass with 61.0t C/ha; whereas the greatest carbon fixation rate was 17.7 t/ha/year in AFS with citrus species. The results suggest that cocoa plantations that include other plant species diversify the production and increase food security and generation of environmental services, such as capturing atmospheric carbon.

3.
Laboratory Animal Research ; : 141-145, 2011.
Artigo em Inglês | WPRIM | ID: wpr-116717

RESUMO

Mycoplasmas are highly fastidious bacteria, difficult to culture and slow growing. Many species of mycoplasmas are important pathogens that cause respiratory infection in laboratory animals and that are known to affect experimental results obtained with contaminated animals. The aim of the present study was to develop a sensitive and specific assay for the detection of mycoplasma species. To this end, we developed a polymerase chain reaction and dot blot hybridization assay (PCR/DBH) for detecting mycoplasma DNA and evaluated it for its sensitivity and specificity. Mycoplasma consensus primer pairs were used for the amplification of target DNA. When PCR product was visually detected, the limit of detection of the PCR test was 10(2) pg of mycoplasma purified DNA. For DBH, the amplified DNA was labeled by incorporation of digoxigenin (DIG). This DIG-labeled probe was capable of detecting 10(4) pg of purified mycoplasma DNA by DBH. PCR/DBH was more sensitive than PCR or DBH alone and was also very specific. Our PCR/DBH assay can be applied efficiently to confirm the presence of mycoplasma species on clinical samples and to differentiate between mycoplasma species infection and other bacterial infections.


Assuntos
Animais , Animais de Laboratório , Bactérias , Infecções Bacterianas , Quimera , Consenso , Digoxigenina , DNA , Limite de Detecção , Mycoplasma , Reação em Cadeia da Polimerase , Sensibilidade e Especificidade
4.
Journal of Genetic Medicine ; : 179-185, 2007.
Artigo em Coreano | WPRIM | ID: wpr-169520

RESUMO

PURPOSE: Catecholamines are the neuro-transmitters in the sympathetic nervous system (SNS) and are activated by stress stimulus. Tyrosine hydroxylase (TH) and Dopamine-beta-Hydroxylase (DBH) are very important enzymes in the catecholamine synthesis. Corticotropin releasing hormone (CRH) is released in the process of reacting to stresses. The aim of this study is to find out what effects immobilization stresses have on the expression of TH, BDH and CRH mRNA in a rat's brains. METHODS: We compare expression levels in rat's brains of TH, DBH and CRH mRNA induced by immobilization stresses between the test group and controled group. The expression levels of TH, DBH and CRH mRNA are measured by RT-PCR and the Western Blotting Analysis (WBA). RESULTS: In brains and adrenal glands of the immobilization stress group, the expression levels of TH and DBH mRNAs are significantly two to three times higher (P<0.01), and CRH mRNAs are approximately one and a half times higher (P<0.05) than those of controlled group. CONCLUSION: This study suggest that the expression levels of TH, DBH and CRH mRNAs are activated by stress stimulus in a rat's brains and adrenal glands.


Assuntos
Animais , Ratos , Glândulas Suprarrenais , Western Blotting , Encéfalo , Catecolaminas , Hormônio Liberador da Corticotropina , Imobilização , RNA Mensageiro , Sistema Nervoso Simpático , Tirosina 3-Mono-Oxigenase
5.
Korean Journal of Anatomy ; : 161-171, 2000.
Artigo em Coreano | WPRIM | ID: wpr-643596

RESUMO

Mongolian gerbil (Meriones unguiculatus) has been as an model animal for studing the neurologic disease because of the long-term survival in the condition of water-deprived desert condition. In order to accomplish the this research, first of all another divided the laboratory animals 10groups. In this study of the long term water deprived condition investigated catecholamine synthetic enzymes, tyrosine hydroxylase(TH), dopamine-beta-hydroxylase (DBH), and phenylethanolamine-N- methyltransferase(PNMT) in the brain by using immunohistochemical stain. The results obtained in this study were summarized as following. 1. It were observed TH-IR cells in substantia nigra pars compacta, ventral tegmental area and substantia nigra pars reticular of Midbrian. Most of them were presented in pars compacta and ventral tegmental area, but a few in pars reticular. TH-IR cell decreased until the 5th water-deprived day, increased from the 10th water-deprived day to the 15th water-deprived day and redecreased in the 20th water-deprived day 2. In locus ceruleus and rubrospinal tract were observed TH-IR cells and a few DBH-IR cell. Therefore there was composed of dopaminergic neuron and noradrenergic neuron. 3. The quantity of dopamin in serum were decreased until the 4th water-deprived day, increased from the 5th water-deprived day, redecreased on the 15th water-deprived day and reincreased from the 20th water-deprived day.


Assuntos
Animais , Neurônios Adrenérgicos , Animais de Laboratório , Encéfalo , Neurônios Dopaminérgicos , Gerbillinae , Locus Cerúleo , Mesencéfalo , Ponte , Substância Negra , Tirosina , Área Tegmentar Ventral
6.
Korean Journal of Anatomy ; : 419-428, 1998.
Artigo em Coreano | WPRIM | ID: wpr-652473

RESUMO

The distributions and morphological characteristics of neurons displaying immunoreactivity to the catecholamine synthetic enzymes tyrosine hydroxylase (TH), dopamine-beta-hydroxylase (DBH), and phenylethanolamine-N-methyltransferase (PNMT) were examined in the adjacent sections of the whole brain in the Striped Field Mouse (Apodemus agrarius coreae) The medulla oblongata were divided into 3 parts (rostral medulla oblongata, area postrema portion of medulla oblongata and caudal medulla oblongata) in this study. In the rostral medulla oblongata, adrenergic (TH-, DBH- and PNMT-positive) neurons were found in dorsal motor nucleus of vagus, nucleus tractus solitarius, dorsal strip and medial longitudinal fasciculus. In the ventrolateral medullary tegmentum of rostral medulla oblongata, adrenergic neurons were found between gigantocellular reticular nucleus and paragigantocellular reticular nucleus. In the area postrema portion of medulla oblongata, noradrenergic neurons were found in the nucleus tractus solitarius, and area postrema. And dopaminergic or adrenergic neurons were also found in dorsal motor nucleus of vagus. In the caudal medulla oblongata, noradrenergic neurons were found in the medial part of nucleus tractus solitarius and superior part of the lateral reticular nucleus.


Assuntos
Animais , Camundongos , Neurônios Adrenérgicos , Área Postrema , Encéfalo , Imuno-Histoquímica , Bulbo , Murinae , Neurônios , Núcleo Solitário , Tirosina 3-Mono-Oxigenase , Tirosina
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