As áreas destinadas à pecuária têm-se expandido sobre áreas de vegetação nativa promovendo transformações na qualidade do solo. O objetivo foi avaliar os atributos de um Neossolo Quartzarênico sob diferentes coberturas vegetais para saber se a degradação do pasto representa a degradação do solo. As áreas avaliadas foram: floresta nativa; capoeira; pastagem sem controle de lotação animal; pastagem em pousio; pastagem com invasoras; pastagem degradada com solo descoberto e invasoras, pastagem degradada com invasoras e espécies arbóreas e pastagem com baixa produção de forragem. Todas as pastagens eram formadas pela gramínea Brachiaria brizantha cv. Marandu. Realizaram-se 128 amostras de solo nas profundidades de 0-5 e 5-10 cm, dentro de cada área de manejo considerada como parcela experimental e a cobertura do solo foi quantificada. Foram mensuradas propriedades químicas e físicas do solo. Os dados foram submetidos a estudo geoestatístico. Foram constatados aumento na resistência mecânica à penetração e diminuição nos teores de matéria orgânica nas áreas mais degradadas. Pasto degradado não representa necessariamente solo degradado enquanto solo degradado está relacionado a pastagem degrada.

The areas for livestock raising have expanded into areas of native vegetation, promoting changes in soil quality. The objective of this study was to evaluate the attributes of a Entisol under different vegetation covers to whether the pasture degradation represents soil degradation. The areas evaluated were: native forest, shrub, uncontrolled grazing animal stocking, grazing in fallow pasture with weeds; degraded pasture with bare soil and weeds, degraded pasture with weeds and tree species and grassland with low forage production. All pastures were formed by Brachiaria brizantha cv. Marandu. Hundred and twenty eight soil samples were collected in 0-5 and 5-10 cm, within each management area, considered as an experimental plot and soil cover was quantified. The chemical and physical properties of the soil were measured. Data were subjected to geoestatistical study. Increase in penetration resistance and decrease in the levels of organic matter were observed in the most degraded areas. Degraded pasture is not necessarily degraded land while degraded soil is related to grazing degrades.

OBJECTIVE: Obstructive sleep apnea is frequent during the acute phase of stroke, and it is associated with poorer outcomes. A well-established relationship between supine sleep and obstructive sleep apnea severity exists in non-stroke patients. This study investigated the frequency of supine sleep and positional obstructive sleep apnea in patients with ischemic or hemorrhagic stroke. METHODS: Patients who suffered their first acute stroke, either ischemic or hemorrhagic, were subjected to a full polysomnography, including the continuous monitoring of sleep positions, during the first night after symptom onset. Obstructive sleep apnea severity was measured using the apnea-hypopnea index, and the NIHSS measured stroke severity. RESULTS: We prospectively studied 66 stroke patients. The mean age was 57.6±11.5 years, and the mean body mass index was 26.5±4.9. Obstructive sleep apnea (apnea-hypopnea index >5) was present in 78.8% of patients, and the mean apnea-hypopnea index was 29.7±26.6. The majority of subjects (66.7%) spent the entire sleep time in a supine position, and positional obstructive sleep apnea was clearly present in the other 23.1% of cases. A positive correlation was observed between the NIHSS and sleep time in the supine position (r s = 0.5; p<0.001). CONCLUSIONS: Prolonged supine positioning during sleep was highly frequent after stroke, and it was related to stroke severity. Positional sleep apnea was observed in one quarter of stroke patients, which was likely underestimated during the acute phase of stroke. The adequate positioning of patients during sleep during the acute phase of stroke may decrease obstructive respiratory events, regardless of the stroke subtype.

A produtividade em sistemas agrícolas de subsistência depende do nível de fertilidade natural do solo. Em condições de relevo forte ondulado, espera-se que a fertilidade do solo se modifique não apenas pelo tipo de uso mas, também, devido à sua posição no relevo. Para avaliar essas modificações, 260 amostras simples de solo (0-20 cm) da microbacia Vaca Brava, PB, representando combinações de três usos do solo, cinco posições no relevo e cinco classes texturais, foram analisadas quanto aos teores de P disponível, bases e acidez trocáveis. Ca e Mg compreenderam 75-80% dos cátions trocáveis, K e Na, de 10 a 15%, e H+Al, 10%; o valor de pH médio foi 5,5, enquanto P Mehlich-1 foi, em média, 3,8 mg kg-1 solo. Apesar dos efeitos significativos (p < 0,05) de uso, relevo e textura nos teores de alguns nutrientes, de forma geral a bacia pareceu relativamente uniforme. A principal diferença entre os usos decorreu da adição de esterco em áreas de roçado e capineira localizadas, preferencialmente, em áreas de pedimento e várzea. Ao redor de 80% das amostras apresentaram teores baixos de P enquanto 70% mostraram teores médios de K; entretanto, utilizando-se o índice K/(Ca+Mg)0,5 conclui-se que a quase totalidade das amostras se apresentou deficiente em K.

Productivity in subsistence agricultural systems relies on natural soil fertility levels. Under strongly undulated relief conditions, it is expected that soil fertility will be determined not only by land use, but also by the position in the landscape. To study these relationships 260 single soil samples (0-20 cm) from the Vaca Brava watershed, Paraiba, representing combinations of three land uses, five positions in the landscape and five textures were analyzed for extractable P, exchangeable bases and soil acidity. Ca and Mg comprised 75-80% of exchangeable cations, K and Na between 10 and 15% and H+Al 10%. The average pH was 5.5, while extractable P (Mehlich-1) averaged 3.8 mg kg-1 soil. Although land use, relief and texture exerted significant effects (p < 0.05) upon certain nutrient concentrations, in a broad sense the watershed appeared relatively uniform. The main effect of land use resulted from the use of animal manure in areas of subsistence agriculture and fodder, which were preferentially located at the base of stopes and low lands positions. Approximately 80% of the samples were low in extractable P, while 70% had medium levels of extractable K. However, when available K was estimated by the K/(Ca+Mg)0,5 ratio, most samples were classified as low.

Estudou-se a seletividade de acaricidas a insetos e ácaros predadores em pomares citrícolas localizados em Monte Alto e Vista Alegre do Alto, SP, em 1993 e 1994. Os acaricidas nas dosagens testadas (em g.i.a/1001) foram: em 1993, pyridaben 20 CE, 20 PM e 75 PM (10 e 15), óxido fenbutatin (40) e testemunha; em 1994, pyridaben 20 CE e pyridaben 75 PM (10 e 20), óxido fenbutatin (40), cyhexatin (25) e testemunha. Larvas e adultos de Pentilia egena Muls. e Coccidophilus citricola Bréthes, adultos de Cycloneda sanguinea L., Azya sp. e Calloeneis sp. e larvas de crisopídeos foram observados nas plantas, previamente e a 1, 3, 7, 10, 14 e 21 dias após a aplicação. Para contagem de Euseius sp. e Iphiseiodes zuluagai Denmark & Muma, 10 folhas do interior da planta foram coletadas e observadas. Os produtos foram classificados em: seletivo (até 25% de mortalidade); levemente tóxico (25 a 50%; moderadamente tóxico (51 a 75%) e tóxico (> 75% de mortalidade). Os resultados indicaram que todos os produtos foram seletivos a adultos de P. egena, porém, pyridaben causou de 25 a 50% e cyhexatin de 51 a 75% de mortalidade de larvas. Pyridaben 20 CE e 75 PM reduziram em 25 a 50% e 51 a 75% respectivamente o número de adultos de C. citricola; já cyhexatin foi tóxico e fenbutatin seletivo a adultos desta espécie. Em relação a larvas de C. citricola mortalidade de 51 a 75% foi causada por pyridaben 20 CE e 75 PM, maior que 75% por cyhexatin e entre 25 e 50% no caso de fenbutatin. Todos os acaricidas foram tóxicos aos ácaros predadores por mais de 21 dias, no entanto, fenbutatin apresentou efeito residual menor (14 dias).

The selectivity of acaricides to predatory insects and mites was studied in two citrus orchards in São Paulo State in 1993 and 1994. Acaricides used (g.a.i /1001) were: in 1993, pyridaben 20 EC, 20 WP and 75 WP (10 and 15), fenbutatin oxide (40) and control; in 1994 pyridaben 20 EC and 75 WP (10 and 20), fenbutatin oxide (40), cyhexatin (25) and control. Evaluations were conducted up to 21 days after spraying. Adults and larvae of Pentilia egena Muls. and Coccidophilus citricola Bréthes, adults of Cycloneda sanguinea L., Azya sp. and Calloeneis sp. and larvae ofchrysopids were counted on the canopy of the tree. Euseius sp. and Iphiseiodes zuluagai Denmark & Muma were counted on 10 leaves from the canopy. The products were classified as: harmless (< 25% of mortality); slightly harmful (25 to 50%); moderately harmful (51 to 75%), and harmful (> 75%). All products were harmless to adults of P. egena; fenbutatin caused < 25% of mortality, pyridaben killed 25 to 50% and cyhexatin 51 to 75% of P. egena larvae. Pyridaben 20 EC and 75 WP were slightly and moderately harmful, cyhexatin caused >75% of mortality and fenbutatin was harmless to adults of C. citricola. Concerning C. citricola, fenbutatin killed 25 to 50% of the larvae, pyridaben 20 EC and 75 WP caused 51 to 75% mortality while cyhexatin caused > 75% mortality. All treatments killed more than 75% of the phytoseiids up to 21 days except fenbutatin oxide which was harmful up to 14 days.