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This study evaluated Carbon (C) storage in different compartments in eucalyptus stands and native Cerrado vegetation. To determine C above ground, an inventory was carried out in the areas where diameter at breast height (DBH), diameter at base height (Db), and total tree height (H) were measured. In the stands, the rigorous cubage was made by the direct method, and in the native vegetation, it was determined by the indirect method through an allometric equation. Roots were collected by direct method using circular monoliths to a depth of 60 cm and determined by the volume of the cylinder. Samples were collected up to 100 cm deep to estimate C stock in the soil. All samples collected directly had C determined using the CHNS elemental analyzer. Gas samples were collected using a manually closed chamber, and the gas concentration was determined by gas chromatography. The results indicate high C storage in the studied areas > 183.99 Mg ha-1, could contribute to CO2 mitigation > 674.17 Mg ha-1. In addition to low emissions (<1 kg ha-1 yr-1) for the three evaluated areas, with no statistical difference in relation to the Global Warming Potential. Concerning the native cerrado vegetation conversion, the "4-year-old eucalyptus stand" seemed to restore the original soil carbon stocks in the first-meter depth, regardless of some losses that might have occurred right after establishment. Conversely, a significant loss of carbon in the soil was observed due to the alternative setting, where similar natural land was converted into agriculture, mostly soybean, and then, years later, turned into the "6-year-old eucalyptus stand" (28.43 Mg ha-1). Under this study, these mixed series of C baselines in landscape transitions have reflected on unlike C dynamics outcomes, whereas at the bottom line, total C stocks were higher in the younger forest (4-year-old stand). Therefore, our finding indicates that we should be thoughtful regarding upscaling carbon emissions and sequestration from small-scale measurements to regional scales.
RESUMO
Forest soils are N2O sources and commonly act as CH4 sinks. This study evaluated the dynamics of the CH4 and N2O fluxes of soils under Eucalyptus plantations and native Cerrado vegetation, as well as possible interactions between environmental factors and fluxes. The study was carried out in the Distrito Federal, Brazil, during 26 months, in three areas: in two stands of the hybrid Eucalyptus urophylla × Eucalyptus grandis, planted in 2011 (E1), and in 2009 (E2) and native Cerrado vegetation (CE). Measurements to determine the fluxes in a closed static chamber were carried out from Oct 2013 to Nov 2015. Soil and climate factors were monitored. During the study period, the mean CH4 fluxes were 22.48, 8.38 and 1.31 μg CH4 m2 h1 and the mean N2O fluxes 5.45, 4.85 and 3.85 μg N2O m2 h1 from E1, E2 and CE, respectively. Seasonality affected plantations in the studied sites. Cumulative CH4 influxes were calculated (year-1: 1.86 to -0.63 kg ha1 yr1; year-2: 1.85 to 1.34 kg ha1 yr1). Cumulative N2O fluxes in the three sites were ≤ 0.85 kg ha1 yr1. The change in land use from Cerrado to Eucalyptus plantations did not significantly changed regarding greenhouse gases (GHG), compared to the native vegetation. Flux rates of both gases (N2O and CH4) were low. Temporal variations in GHG fluxes and different ages of the stands did not cause significant differences in cumulative annual fluxes.
Assuntos
Eucalyptus/química , Gases de Efeito Estufa , Metano , Árvores/química , Óxido Nitroso , BrasilRESUMO
Forest soils are N2O sources and commonly act as CH4 sinks. This study evaluated the dynamics of the CH4 and N2O fluxes of soils under Eucalyptus plantations and native Cerrado vegetation, as well as possible interactions between environmental factors and fluxes. The study was carried out in the Distrito Federal, Brazil, during 26 months, in three areas: in two stands of the hybrid Eucalyptus urophylla × Eucalyptus grandis, planted in 2011 (E1), and in 2009 (E2) and native Cerrado vegetation (CE). Measurements to determine the fluxes in a closed static chamber were carried out from Oct 2013 to Nov 2015. Soil and climate factors were monitored. During the study period, the mean CH4 fluxes were 22.48, 8.38 and 1.31 μg CH4 m2 h1 and the mean N2O fluxes 5.45, 4.85 and 3.85 μg N2O m2 h1 from E1, E2 and CE, respectively. Seasonality affected plantations in the studied sites. Cumulative CH4 influxes were calculated (year-1: 1.86 to -0.63 kg ha1 yr1; year-2: 1.85 to 1.34 kg ha1 yr1). Cumulative N2O fluxes in the three sites were ≤ 0.85 kg ha1 yr1. The change in land use from Cerrado to Eucalyptus plantations did not significantly changed regarding greenhouse gases (GHG), compared to the native vegetation. Flux rates of both gases (N2O and CH4) were low. Temporal variations in GHG fluxes and different ages of the stands did not cause significant differences in cumulative annual fluxes.(AU)
Assuntos
Eucalyptus/química , Metano , Óxido Nitroso , Gases de Efeito Estufa , Árvores/química , BrasilRESUMO
In the Brazilian Cerrado, despite the increasing adoption of no-till systems, there are still extended areas under conventional soil management systems that reduce soil carbon (C) and nitrogen (N) stocks and increase the emissions of greenhouse gases, such as nitrous oxide (N2O). Conservation agroecosystems, such as no-till, have been proposed as a strategy to mitigate agriculture-induced climatic changes through reductions in N2O emissions. However, the relationship between organic matter and N2O emissions from soils under different agroecosystems is not yet clear. This study hypothesized that agroecosystems under no-till promote an accumulation of labile and stable SOM fractions along with a reduction of N2O emissions. This study evaluated the effects of crop-rotation agroecosystems: i) on C and N pools and labile and stable SOM fractions; ii) on cumulative N2O emissions; and iii) on the relationships between SOM fractions and N2O emissions. The agricultural systems consisted of: (I) soybean followed by sorghum under no-tillage (NT1); (II) maize followed by pigeon pea under no-tillage (NT2); (III) soybean under conventional tillage followed by fallow soil (CT); (IV) and native Cerrado (CER). After CT for 18years, following the replacement of CER, the soil C stock in the 0-20cm layer was reduced by 0.64tha-1year-1. The no-till systems were more efficient in accumulating labile and stable C fractions with values close to those observed under CER, and were directly related to lower soil N2O emissions. The cumulative pattern of N2O emissions was inverse to that of the following SOM fractions: microbial biomass carbon, permanganate-oxidizable carbon, particulate organic carbon, inert carbon, and humic substances. Based on principal component analysis, the CT was generally separated from the other land use systems. This separation was strongly influenced by the low C contents in the different SOM fractions and higher N2O emissions promoted by the CT.
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Objective: To assess the metabolic alterations of the thalamus in subjects with schizophrenia compared to healthy subjects and to investigate whether specific schizophrenic symptoms are associated with metabolic alterations measured by 1H MRS. Methods: This is a case-control study including patients with schizophrenia diagnosed usingthe Diagnostic and Statistical Manual of Mental Disorders - Fourth Edition, DMS-IV and the Operational CriteriaChecklist for Psychotic Illness (OPCRIT). Proton magnetic resonance spectroscopy (1H MRS) was used to assess metabolite concentrations (N-acetylaspartate, choline, creatinine, myoionositol and lactacte) in the left and rightthalamus of 13 patients with schizophrenia and 13 healthy controls. Results: In this study, concentrations of specific metabolites in the thalamus, determined by 1H MRS, were similar for individuals with schizophrenia andcontrols. It was observed that cases with family history of schizophrenia and disorganized speech demonstrated areduction in the ratio of the metabolites NAA /Cho in the thalamic nuclei on the right side. However, those withorganized delusions, hallucinations and non-affective auditory hallucinations had an increase of metabolites on theright side compared to the left thalamus. Decreased thalamic metabolic activity in patients with positive symptomswas observed in contrast with those who had well-organized delusions and auditory non-affective hallucinations,core symptoms of schizophrenia. Conclusion: A lateralized thalamic involvement was verified, suggesting thatorganic and genetic factors compromise the right thalamus and that the disorganization associated with delusionsand hallucinations compromises the left thalamic nuclei. Further studies to investigate the correlation betweensymptoms and thalamic dysfunction are warranted. (Rev Neuropsiquiatr 2011;74:183-190).
Objetivo: Evaluar las alteraciones metabólicas del tálamo en personas con esquizofrenia comparándolas con controles sanos e investigar si los síntomas específicos de la esquizofrenia están vinculados a alteraciones metabólicas medidas por 1H MRS. Métodos: Se realizó la espectroscopía por resonancia magnética (1H-MRS) para estimar concentraciones de metabolitos (N-acetil- aspartato, colina creatinina, mioionositol y lactato) en el tálamo izquierdo y derecho de 13 pacientes con esquizofrenia y 13 controles. Resultados: Las concentraciones de metabolitos específicos en el tálamo fueron iguales para las personas con esquizofrenia y los controles. Se observó que los pacientes con historia familiar de esquizofrenia y aquellos que presentaban lenguaje desorganizado tenían una reducción de los metabolitos NAA/Co en los núcleos talámicos de la derecha. Sin embargo, en aquellos delirios ordenados, alucionaciones no afectivas y alucinaciones auditivas los metabolitos del lado derecho tuvieron cierto aumento con relación a los núcleos talámicos de la izquierda. Se encontró una reducción en la actividad metabólica talámica en los pacientes con síntomas positivos, al contrario de aquellos que presentaron delirios bien ordenados y alucinaciones auditivas no afectivas, los síntomas más nucleares de la esquizofrenia. Conclusión: Se verificó cierta lateralización del envolvimiento talámico, sugiriendo que los factores orgánicos y los genéricos comprometen el tálamo derecho y que la desorganización asociada a los delirios y alucionaciones compromete los núcleos talámicos de la izquierda. Más estudios son necesarios para investigar la validez de la correlación entre síntomas y disfunción talámica.
Assuntos
Humanos , Acetilcolina , Colina , Espectroscopia de Ressonância Magnética , Esquizofrenia , Tálamo , Estudos de Casos e ControlesRESUMO
Despite the implication of fronto-striatal circuits in attention-deficit/hyperactivity disorder (ADHD), there is a lack of information on the role of these regions, especially the thalamus, in the heterogeneity of ADHD. We assessed the (1)H-magnetic resonance spectroscopy profile in ventromedial prefrontal cortex (VMPFC)-thalamic-striatal regions bilaterally in three groups of subjects (age range 18-24 years old): ADHD inattentive type (ADHD-I; n = 9), ADHD combined type (ADHD-C; n = 10) and non-ADHD controls (n = 12). The peaks of N-acetylaspartate, Choline (Cho), myo-inositol (mI), creatine (Cr) and glutamate-glutamine-GABA (Glx) to Cr were calculated. Subjects with ADHD-C showed lower mI/Cr ratio in the right VMPFC than controls, higher Cho/Cr ratio in the left thalamus-pulvinar than the ADHD-I group and higher Glx/Cr ratio in left putamen than individuals with ADHD-I and controls. This metabolic profile suggests a disruption of fronto-striato-thalamic structures in the ADHD-C as a result of lower neuronal energetic metabolism.
Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico por imagem , Transtorno do Deficit de Atenção com Hiperatividade/metabolismo , Espectroscopia de Ressonância Magnética/métodos , Prosencéfalo/diagnóstico por imagem , Prosencéfalo/metabolismo , Adolescente , Ácido Aspártico/análogos & derivados , Ácido Aspártico/análise , Ácido Aspártico/metabolismo , Transtorno do Deficit de Atenção com Hiperatividade/fisiopatologia , Colina/análise , Colina/metabolismo , Corpo Estriado/diagnóstico por imagem , Corpo Estriado/metabolismo , Corpo Estriado/fisiopatologia , Creatina/análise , Creatina/metabolismo , Diagnóstico Diferencial , Metabolismo Energético/fisiologia , Feminino , Lobo Frontal/diagnóstico por imagem , Lobo Frontal/metabolismo , Lobo Frontal/fisiopatologia , Lateralidade Funcional/fisiologia , Ácido Glutâmico/análise , Ácido Glutâmico/metabolismo , Glutamina/análise , Glutamina/metabolismo , Humanos , Inositol/análise , Inositol/metabolismo , Masculino , Prosencéfalo/fisiopatologia , Pulvinar/diagnóstico por imagem , Pulvinar/metabolismo , Pulvinar/fisiopatologia , Putamen/diagnóstico por imagem , Putamen/metabolismo , Putamen/fisiopatologia , Cintilografia , Tálamo/diagnóstico por imagem , Tálamo/metabolismo , Tálamo/fisiopatologia , Adulto Jovem , Ácido gama-Aminobutírico/análise , Ácido gama-Aminobutírico/metabolismoRESUMO
OBJECTIVES: The present study was designed to evaluate the effect of twelve weekly sessions of the cognitive-behavioral program originally known as the Integriertes Psychologisches Therapieprogramm für Schizophrene Patienten, designated the Integrated Psychological Therapy (IPT) program in English, on cognition, social adjustment and quality of life in schizophrenic outpatients, comparing it to the effect of treating such patients as usual. METHOD: Fifty-six adult outpatients (from 18 to 65 years of age) with ICD-10-based diagnoses of schizophrenia were randomly assigned to two different groups: active intervention (IPT group); and treatment as usual (control group). Outcome measures were quality of life (as determined using the WHOQOL-Bref), cognition (Mini-Mental State Examination and Word Recall Test), global functioning (DSM-IV Global Assessment of Functioning Scale), social functioning (Social and Occupational Functioning Assessment Scale) and social adjustment (Social Adjustment Scale). RESULTS: The findings suggest that, in comparison with treatment as usual (control group), the twelve-session IPT program had a positive effect on several outcome measures: cognition in the domains of spatiotemporal orientation (p = 0.051) and memory (p = 0.031); overall social adjustment (p = 0.037), leisure/social life (p = 0.051) and family relations (p = 0.008); overall functioning (p = 0.000); social-occupational functioning (p = 0.000); and quality of life in the psychological domain (p = 0.021). CONCLUSIONS: The twelve-session cognitive-behavioral IPT intervention demonstrated superiority over treatment as usual in its effects on cognition, social adjustment and quality of life. Studies involving larger samples, longer follow-up periods and additional outcome measures are needed in order to assess the specific effects on dimensions of social functioning, cognitive functioning and quality of life in patients with schizophrenia.
Assuntos
Terapia Cognitivo-Comportamental/métodos , Prestação Integrada de Cuidados de Saúde , Esquizofrenia/terapia , Psicologia do Esquizofrênico , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Escalas de Graduação Psiquiátrica , Psicoterapia de Grupo/métodos , Qualidade de Vida , Esquizofrenia/reabilitação , Ajustamento Social , Fatores Socioeconômicos , Resultado do TratamentoRESUMO
OBJECTIVES: The present study was designed to evaluate the effect of twelve weekly sessions of the cognitive-behavioral program originally known as the Integriertes Psychologisches Therapieprogramm für Schizophrene Patienten, designated the Integrated Psychological Therapy (IPT) program in English, on cognition, social adjustment and quality of life in schizophrenic outpatients, comparing it to the effect of treating such patients as usual. METHOD: Fifty-six adult outpatients (from 18 to 65 years of age) with ICD-10-based diagnoses of schizophrenia were randomly assigned to two different groups: active intervention (IPT group); and treatment as usual (control group). Outcome measures were quality of life (as determined using the WHOQOL-Bref), cognition (Mini-Mental State Examination and Word Recall Test), global functioning (DSM-IV Global Assessment of Functioning Scale), social functioning (Social and Occupational Functioning Assessment Scale) and social adjustment (Social Adjustment Scale). RESULTS: The findings suggest that, in comparison with treatment as usual (control group), the twelve-session IPT program had a positive effect on several outcome measures: cognition in the domains of spatiotemporal orientation (p = 0.051) and memory (p = 0.031); overall social adjustment (p = 0.037), leisure/social life (p = 0.051) and family relations (p = 0.008); overall functioning (p = 0.000); social-occupational functioning (p = 0.000); and quality of life in the psychological domain (p = 0.021). CONCLUSIONS: The twelve-session cognitive-behavioral IPT intervention demonstrated superiority over treatment as usual in its effects on cognition, social adjustment and quality of life. Studies involving larger samples, longer follow-up periods and additional outcome measures are needed in order to assess the specific effects on dimensions of social functioning, cognitive functioning and quality of life in patients with schizophrenia.
OBJETIVOS: O presente estudo foi designado para avaliar o efeito de 12 sessões semanais do programa cognitivo-comportamental IPT (Integrated Psychological Therapy - Integriertes psychologisches Therapieprogramm für schizophrene Patienten - Terapia Psicológica Integrada), comparado ao tratamento usual sobre o funcionamento cognitivo, ajustamento social e qualidade de vida em pacientes ambulatoriais com esquizofrenia. MÉTODO: Cinqüenta e seis pacientes ambulatoriais adultos (idade entre 18 e 65 anos) com diagnóstico de esquizofrenia pela CID-10, foram aleatoriamente designados para dois grupos: intervenção ativa (IPT) e tratamento usual (grupo controle). As diferenças de medidas de resultados foram em qualidade de vida (WHOQOL-bref), cognição (Mini-Mental State Examination e word-span), funcionamento global (Global Assessment of Functioning-DMS-IV), funcionamento social (Social and Occupational Functioning Assessment Scale-DSM-IV) e ajustamento social (Social Adjustment Scale). RESULTADOS: Os achados sugerem que 12 sessões do programa IPT mostraram um efeito positivo sobre várias medidas de resultado comparado ao grupo controle (tratamento usual): cognição nos domínios de orientação no tempo e no espaço (p = 0,045) e memória (p = 0,031); ajustamento social geral (p = 0,037), lazer e vida social (p = 0,051), relações familiares (p = 0,008); funcionamento global (p = 0,000); funcionamento sócio-ocupacional (p = 0,000); e qualidade de vida no domínio psicológico (p = 0,021). CONCLUSÃO: A intervenção cognitivo-comportamental de 12 sessões do IPT demonstrou superioridade de efeito sobre cognição, ajustamento social e qualidade de vida comparado ao tratamento usual. Estudos com amostras maiores, maior tempo de seguimento (follow-up) e medidas adicionais de desfechos são necessários para avaliar efeitos específicos sobre dimensões de funcionamento cognitivo, social e qualidade de vida em esquizofrênicos.