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Excessive intensification of dairy and beef cattle production systems in the industrialised countries has led to serious problems of pollution of water resources and the atmosphere. In order to develop an appropriate alternative, a few studies have been made by various research teams in Brazil, using low fertiliser inputs and modest animal stocking rates. The objective of this present study was to evaluate the effect of different stocking rates of beef cattle, and the introduction of a forage legume (Desmodium ovalifolium (Prain) Wall.), on the long-term sustainability of pastures of Brachiaria humidicola (Rendle) Schweick established in the Atlantic forest region of Brazil in the extreme south of the State of Bahia. Annual maintenance fertilisation was restricted to additions of 11 and 6 kg ha⁻¹ of P and K, respectively (and no N). Live weight gain (LWG) of Zebu steers was evaluated for stocking rates of 2, 3 and 4 head ha⁻¹ during six grazing periods from 1988 to 1997. Forage intake and the proportion of legume in the acquired ration was determined using steers fitted with oesophageal fistulae. The bolus samples were analysed manually in 1988-1989, and using the ¹³C natural abundance technique in 1995. There was no significant response of LWG to the presence of the legume in the acquired ration. LWG in the final grazing period (1995-1996) was similar to that recorded in 1988-1989 at all stocking rates, suggesting that this management regime resulted in long-term sustainable production even in the absence of the legume or of a N fertiliser input. This was confirmed by the soil fertility analyses for 1988 and 1997, where only levels of P showed a significant decrease. The net aerial primary productivity (NAPP) of the pasture was determined for 1995, the largest component being deposited litter (21-33 Mg DM ha⁻¹ year⁻¹), followed by forage intake (6.4-12.2 Mg DM ha⁻¹ year⁻¹).

The impact of forest clearance, and its replacement by Brachiaria pastures, on soil carbon reserves has been studied at many sites in the Brazilian Amazonia, but to date there appear to be no reports of similar studies undertaken in the Atlantic forest region of Brazil. In this study performed in the extreme south of Bahia, the changes in C and N content of the soil were evaluated from the time of establishment of grass-only B. humidicola and mixed B. humidicola/Desmodium ovalifolium pastures through 9 years of grazing in comparison with the C and N contents of the adjacent secondary forest. The decline in the content of soil C derived from the forest (C3) vegetation and the accumulation of that derived from the Brachiaria (C4) were followed by determining the 13C natural abundance of the soil organic matter (SOM). The pastures were established in 1987, 10 years after deforestation, and it was estimated that until 1994 there was a loss in forest-derived C in the top 30 cm of soil of approximately 20% (9.1 Mg C ha−1). After the establishment of the pastures, C derived from Brachiaria accumulated steadily such that at the final sampling (1997) it was estimated 13.9 Mg ha−1 was derived from this source under the grass-only pasture (0–30 cm). Samples taken from all pastures and the forest in 1997 to a depth of 100 cm showed that below 40 cm depth there was no significant contribution of the Brachiaria-derived C and that total C reserves under the grass/legume and the grass-only pastures were slightly higher than under the forest (not significant at P=0.05). The more detailed sampling under the pastures showed that to a depth of 30 cm there was significantly (P<0.05) more C under the mixed pasture than the grass-only pasture. It was estimated that from the time of establishment the apparent rate of C accumulation (0–100 cm depth) under the grass/legume pastures (1.17 Mg ha−1 yr−1) was almost double that under the grass-only pastures (0.66 Mg ha−1 yr−1). The data indicated that newly incorporated SOM derived from the Brachiaria had a considerably higher C:N ratio than that present under the forest.

Over the last 25 years more than 70 million ha of the native vegetation in Brazil have been replaced by pastures for beef production planted to grasses of the genus Brachiaria, and to a lesser extent Andropogon gayanus, both of African origin. Some years after implantation, these pastures decline in productivity, probably due to low availability of P, and immobilisation of N in the soil due to the large quantities of senescent leaves (litter) of high C:N ratio deposited on the soil surface. In this paper we report the effects of the introduction of a forage legume (Desmodium ovalifolium) and different animal stocking rates on the deposition and decomposition of plant litter in pastures of Brachiaria humidicola at a site in the coastal Atlantic forest region of the south of Bahia State (Brazil). Litter existing on the ground, and that deposited in 14-day periods, was monitored at monthly intervals during 3 years of the study. Doubling the stocking rate from 2 to 4 animals ha-1 caused a highly significant decrease in litter deposition, but the presence of the legume in the sward had little effect. Calculations made directly from the quantities of litter deposited in the 14-day periods showed that between 15 and 18 tons of litter dry matter (dm) were deposited annually, but the relatively small quantities of existing litter (annual means of 0.8 to 1.5 t dm ha-1), showed that decomposition was rapid, showing values for half life of between 22 and 33 days. This technique was assumed to underestimate true litter disappearance rates, as with such rapid decomposition a significant proportion of the litter disappeared within the 14-day collection periods. An equation was developed to correct for this loss of litter during the collection periods and corrected litter decomposition constants of 0.037 to 0.097 g g-1 day-1 were recorded resulting in half lives of between 9 and 20 days. Using these data and adding them to estimates of animal consumption the net aerial primary productivity (NAPP) of the pastures ranged from 28 to 34 t dry matter ha-1 yr-1. Experiments with litter bags, and a \"covered litter\" system which allowed access of soil fauna to the litter, indicated that soil faunal activity had little impact on litter disappearance and such techniques underestimated true litter decomposition by at least an order of magnitude. We suggest that this underestimation is due to the fact, that in contrast to litter bags, in the open field situation fresh litter is being added continuously. As this material consists of both easily degradable (\"active\") and recalcitrant fractions, the easily degradable fraction fuels an active microbial biomass which continuously degrades the less decomposable material. It is concluded that the approach used in this study gives more realistic, and much higher estimates, of net primary aerial production of tropical grasslands and pastures than techniques heretofore utilised.

It has been shown that with careful grazing management and addition of P and K, but not N, fertilisers Brachiaria pastures are able to maintain sustainable live weight gains over many years. However, standard on-farm practice, which generally involves high stocking rates, leads after a few years to pasture decline due mainly to N deficiency for grass regrowth. To generate an understanding of the mechanism of pasture decline and possible management options to mitigate this process, a study was performed in the Atlantic forest region of the south of Bahia state to study the N dynamics in pastures of Brachiaria humidicola subject to three different stocking rates of beef cattle, with and without the presence of the forage legume Desmodium ovalifolium. Despite the fact that the C:N ratio of the deposited litter was high (60 to 70) the rate of decomposition was very rapid (k similar to -0.07 g g super(-1) day super(-1)) and annual rates of N turnover through the litter pathway were between 105 and 170 kg N ha super(-1) year super(-1). In the grass-only pastures as stocking rate increased from 2 to 3 head ha super(-1), N recycled in the litter decreased by 11%, but a further increase to 4 head ha super(-1) decreased N recycling by 30% suggesting that beyond a certain critical level higher grazing stocking rates would lead to pasture decline if there was no N addition. High stocking rates decreased the proportion of the legume in the sward, but at all rates the concentration of N in both the green and dead grass in the forage on offer and in the litter was higher in the mixed sward. The presence of the legume caused a decrease in the C:N ratio of the microbial biomass while both soil N mineralisation and nitrification increased. This increased rate of turnover of the microbial biomass and the contribution of N sub(2) fixation to the legume resulted in large increases in the N recycled via litter deposition ranging from 42 to 155 kg N ha super(-1) year super(-1).

Many, but not all, legumes of tropical origin, transport fixed N from the nodules to the shoot tissue in the form of ureides, and the mineral N absorbed from the soil is principally transported in the form of nitrate. The analysis of stem xylem sap, or hot-water extracts of stem tissue, for ureide and nitrate has been used successfully to quantify BNF contributions to several grain legumes and more recently to some shrub and forage legumes. The objective of this study was to investigate the application of this technique to the quantification of the contribution of BNF to the forage legume Desmodium ovalifolium by comparing the relative ureide abundance (RUA) of stem extracts of this plant with simultaneous estimates of BNF obtained using the 15N isotope dilution technique. The first experiment was performed in pots of soil, taken from a grazing study, amended with 15N-labelled organic matter at four different application rates. The ureide concentration in the stem extracts reflected the changes in BNF activity during plant growth and the RUA was closely correlated with the proportion of N derived from BNF as determined from the 15N technique (r2 = 0.86 and 0.88 for inoculated and non-inoculated plants, respectively). The use of a calibration curve derived from a previous study where the same legume was fed increasing concentrations of 15N labelled nitrate in sand/vermiculite culture, resulted in an over-estimation of the BNF contribution which may have been due to a significant uptake of ammonium from this acidic soil. The second experiment was performed in field plots and a good agreement was found between the estimates of BNF derived from using the ureide and 15N dilution techniques at two harvests six months apart. The uptake of soil N by the D. ovalifoliumand two forage grasses (Brachiaria humidicola and Panicum maximum) was estimated using an in situ soil core technique, and, while the uptake of N by the grasses was successfully estimated, this technique underestimated the N derived from the soil by the legume as determined by the ureide and 15N dilution techniques.

Este programa revisara las estrategias para que las personas mayores dejen de fumar. Las estrategias se pondran a prueba en varias combinaciones, como consejeria personal y telefonica, parches de nicotina, prescripciones medicas para dejar de fumar y materiales educativos. Se ha demostrado que tanto los servicios de apoyo y terapias han ayudado a las personas a dejar de fumar. El estudio tiene como objetivo determinar cuales son las mas eficaces para las personas de edad avanzada. Los beneficiarios de Medicare que se inscriban en este programa recibiran terapia gratuita para dejar de fumar, que puede incluir desde consejeria medica hasta medicinas para ayudarlos a dejar de fumar. Generalmente Medicare no cubre la terapia para dejar de fumar, pero la cubrira para aquellos que se inscriban en este programa.

\"Este es un nuevo enfoque para dar lugar a un cuidado que mejor calidad en los asilos de nuestro pais\", dijo Tommy G. Thompson, secretario del HHS. \"No solo los consumidores, estaran mejor informados, sino que los propios asilos podran ver claramente lo que deben hacer para mejorar su calidad. Tendran que competir en la palestra de la calidad. Es un esfuerzo de gran escala, y crecera y mejorara con el tiempo, con un mejoramiento de la informacion y nuevos niveles de colaboracion para ayudar a los asilos a garantizar una atencion de alta calidad\". Al visitar la pagina electronica del Medicare, los consumidores y otras personas a cargo de dar cuidados pueden investigar medidas especificas de calidad sobre asilos de ancianos en sus zonas. Las medidas se calculan a partir de datos de evaluacion de residentes, compilados habitualmente a intervalos especificados durante su estancia en el asilo. La informacion concierne a las capacidades y las condiciones fisicas y clinicas de los residentes. CMS ha calculado 10 de las medidas de calidad para informacion al publico y mejoramiento. Estan divididas en dos categorias: residentes a largo plazo y residentes a corto plazo. Entre las medidas estan:

El ano pasado existio retraso en la distribucion de la vacuna contra la gripe (Flu), dejando a muchas personas con la preocupacion de donde podian recibirla. Este ano, la Coalicion de la Gripe y Neumonia en Florida (Florida Flu and Pneumonia Coalition) ha disenado una pagina electronica en el Internet, situada en www.ffpcoalition.org, en la cual puede encontrar informacion acerca de la vacuna. Comenzando este otono, usted podra ingresar directamente a las paginas electronicas de las diferentes companias que proveeran la vacuna contra la gripe. En estas paginas encontrara una lista con los dias y lugares en donde se realizaran las vacunaciones.

* Usted permanecera parada frente a una maquina especial de rayos-X, mientras una tecnologa entrenada para realizar este procedimiento colocara uno de sus senos sobre una bandeja plastica. Al mismo tiempo otra bandeja plastica sera colocada sobre su seno aplicando un poco de presion para poder obtener una radiografia adecuada. Algunas veces la cita para una mamografia puede tomar algunas semanas o tal vez meses, por esto las mujeres deben llamar ahora y hacer la cita. Si necesita mas informacion sobre los centros de mamografias en su area, debe hablar con su doctor. Tambien puede tener mas informacion llamando a la linea de ayuda en Florida, 1-800-844-0795. Representantes bilingUes estan disponibles desde las 8 a.m. hasta 5 p.m. Tambien puede ingresar a la pagina www.fmqai.com y seleccionar el area con el nombre de \"Mammography in Florida Consumer Guide\". Si su Medicare es administrado por un HMO, debe comunicarse con el centro de atencion al cliente, llamando al numero telefonico que se encuentra al reverso de su tarjeta de identificacion.

* La neumonia es unas infeccion causada por cierto tipo de bacterias. Estas bacterias pueden atacar a diferentes partes del cuerpo. Cuando estas bacterias invaden a los pulmones se desarrolla en el tipo mas comun de neumonia. Si las mismas bacterias invaden el torrente sanguineo, pueden ocasionar una infeccion llamada bacteriemia. * La vacuna contra la neumonia no contiene bacterias vivas, por lo cual no puede causarle neumonia. * Usted puede recibir la vacuna contra la neumonia en cualquier momento del ano. Puede recibirla conjuntamente con la vacuna contra la gripe o \"flu\" (solo tiene que ser aplicada en el otro brazo).