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Physical and chemical properties of hydromorphic soils of two inland valley swamps (IVS) in the rain forest zone of Nigeria were studied to assist in predicting water movement and soil management for their effective uses. Soils of Abakaliki swamp are generally silty clay with the silt content ranging.from 204 to 562g kg-1 in the surface horizons whereas the silt content ofpedons on Bende swamp seldom exceed 200g kg·1• Results of particle - size distribution of the soils imply that both soils would have the ability of retaining high amount of water. However, the high silt content of the soils of Abakaliki swamp in addition to clay would enhance much more water retention than the Bende soils. In general, the soils have acidic soil reactions for which high precipitation in the area and leaching effects have been implicated The effective cation exchange capaci1y (CECe) values af the soils were generally low: organic carbon content and Bray-I. Pvalues ofthe·surface horizons ranged between 9.3g kg-1 and 23.9g kg-1 and from 1.0 mg kg -J to 9.0 mg kg -I respectively. The acidic reaction of the surface horizons of the soils could be implicated for low Bray - 1 P. Application of non-acidifying fertilizer. would therefore be necessary lo ameliorate the poor fertility.Keywords: Hydromorphic soils, leaching, swamp, active iron ratio

The Clay mineralogy and pedogenic processes in soil of two inland va/Jey swamps were investigated. Both field morphologic observations and particle size distribution indicate /ithologic discontinues in only two (pedons AB-2 and AB-5) of the nine pedons studied. Clay minera/Ogy was predominantly kaolinitic except in pedons BD-1 and BD-2 which contained some degraded mica minerals. Ferro/ysis was well demonstrated in pedons BD-1 and BD-2. Decomposition processes of minerals Jed to the fonnation of some degraded mica.Keywords: clay, ferrolysis, kaolinite

Lowland sawah is viewed as a sustainable alternative to traditional rice culture in West Africa. Sawah (a bund-demarcated, puddled, leveled, and water-regulated rice field) has received growing research attention lately, but no data exist yet on the system’s long-term agronomic impact. In a clayey inland-valley soil in southern Ghana, 10-year-old sawah plots (OSP), fresh sawah plots (FSP), and non-sawah plots (NSP) were maintained under both ponded and non-ponded conditions in 2007. The OSP enhanced soil status of exchangeable nutrients compared to NSP. There were relative improvements in soil bulk density, total porosity, and field moisture content (OSP ≥ FSP > NSP), with clear benefits of ponding over non-ponding in OSP. The NSP was so unsustainable that it showed less favourable values of these variables than an adjacent fallowed plot. These soil variables deteriorated with time, with significant differences in FSP. Soil moisture retention data for tension range of 0-300 kPa depicted the importance of puddling and ponding. During 2001-2009, OSP consistently out-yielded NSP by five times on average. During 2007-2009 when all three plots co-existed, grain yields averaged 5.80, 4.80 and 1.10 Mg ha−1 in OSP, FSP and NSP, respectively. In 2007 yields, OSP minus FSP was higher than NSP; in 2008/2009, the opposite prevailed. These results highlight the agronomic benefits of continuous sawah-based rice production. Although the positive effects of puddling on the soil hydrophysical properties were largely responsible for the wide margin in yield between sawah and traditional systems, the latter lacked other yield-enhancing factors, particularly bunds for water control, were also lacking in the latter., Las tierras bajas del sawah (campos de arroz encharcados y delimitados por lomos de inundación, dotados de una buena nivelación del terreno y regulación del agua) constituyen una alternativa sostenible al sistema tradicional de producción de arroz en África Occidental. El sawah ha despertado una creciente atención, pero aún no existen datos concretos sobre su impacto agronómico a largo plazo. En el año 2007, bajo un suelo arcilloso de valle interior, se llevaron a cabo unos ensayos de cultivo de arroz tanto bajo condiciones de inundación permanente como temporal, para comparar parcelas de sawah de 10 años de antigüedad (OSP) con otras de nueva implantación de sawah (FSP) y con parcelas no sometidas al sawah (NSP). Se observó un incremento de la fertilidad del suelo bajo OSP en comparación con NSP. Otras propiedades del suelo, como densidad aparente, porosidad total y contenido de agua a capacidad de campo mostraron únicamente mejoras relativas (OSP ≥ FSP> NSP), indicando los beneficios derivados del encharcamiento sólo en OSP. En NSP se obtuvieron peores resultados que en el caso de los barbechos adyacentes. En FSP, los atributos de suelos analizados presentaron diferencias significativas con el tiempo. El contenido de humedad alcanzado a la tensión 0-300 kPa expresa la importancia de la práctica de la inundación y del establecimiento de lomos en la delimitación de las parcelas. Entre 2001 y 2009, la producción de arroz en OSP fue 5 veces mayor que en NSP. Entre 2007 y 2009, cuando los tres sistemas coexistieron, la producción de grano fue 5,80, 4,80 y 1,10 Mg ha-1 en OSP, FSP y NSP, respectivamente. En 2007 la producción fue OSP menos FSP>NSP. Sin embargo, en 2008/2009 resultó al contrario. Estos resultados ponen de manifiesto las ventajas agronómicas del sawah en la producción de arroz.

Cancer dormancy is a stage in tumor progression in which residual disease remains occult and asymptomatic for a prolonged period of time. Dormant tumor cells can be present as one of the earliest stages in tumor development, as well as a stage in micrometastases, and/or minimal residual disease left after an apparently successful treatment of the primary tumor. The general mechanisms that regulate the transition of disseminated tumor cells that have lain dormant into a proliferative state remain largely unknown. However, regulation of the growth from dormant tumor cells may be explained in part through the interaction of the tumor cell with its microenvironment, limitations in the blood supply, or an active immune system. An understanding of the regulatory machinery of these processes is essential for identifying early cancer biomarkers and could provide a rationale for the development of novel agents to target dormant tumor cells. This review focuses on the different signaling models responsible for early cancer dissemination and tumor recurrence that are involved in dormancy pathways. Clin Cancer Res; 18(3); 645-53. (C)2011 AACR.

Lowland sawah is viewed as a sustainable alternative to traditional rice culture in West Africa. Sawah (a bund-demarcated, puddled, leveled, and water-regulated rice field) has received growing research attention lately, but no data exist yet on the system’s long-term agronomic impact. In a clayey inland-valley soil in southern Ghana, 10-year-old sawah plots (OSP), fresh sawah plots (FSP), and non-sawah plots (NSP) were maintained under both ponded and non-ponded conditions in 2007. The OSP enhanced soil status of exchangeable nutrients compared to NSP. There were relative improvements in soil bulk density, total porosity, and field moisture content (OSP ≥ FSP > NSP), with clear benefits of ponding over non-ponding in OSP. The NSP was so unsustainable that it showed less favourable values of these variables than an adjacent fallowed plot. These soil variables deteriorated with time, with significant differences in FSP. Soil moisture retention data for tension range of 0-300 kPa depicted the importance of puddling and ponding. During 2001-2009, OSP consistently out-yielded NSP by five times on average. During 2007-2009 when all three plots co-existed, grain yields averaged 5.80, 4.80 and 1.10 Mg ha−1 in OSP, FSP and NSP, respectively. In 2007 yields, OSP minus FSP was higher than NSP; in 2008/2009, the opposite prevailed. These results highlight the agronomic benefits of continuous sawah-based rice production. Although the positive effects of puddling on the soil hydrophysical properties were largely responsible for the wide margin in yield between sawah and traditional systems, the latter lacked other yield-enhancing factors, particularly bunds for water control, were also lacking in the latter. Las tierras bajas del sawah (campos de arroz encharcados y delimitados por lomos de inundación, dotados de una buena nivelación del terreno y regulación del agua) constituyen una alternativa sostenible al sistema tradicional de producción de arroz en África Occidental. El sawah ha despertado una creciente atención, pero aún no existen datos concretos sobre su impacto agronómico a largo plazo. En el año 2007, bajo un suelo arcilloso de valle interior, se llevaron a cabo unos ensayos de cultivo de arroz tanto bajo condiciones de inundación permanente como temporal, para comparar parcelas de sawah de 10 años de antigüedad (OSP) con otras de nueva implantación de sawah (FSP) y con parcelas no sometidas al sawah (NSP). Se observó un incremento de la fertilidad del suelo bajo OSP en comparación con NSP. Otras propiedades del suelo, como densidad aparente, porosidad total y contenido de agua a capacidad de campo mostraron únicamente mejoras relativas (OSP ≥ FSP> NSP), indicando los beneficios derivados del encharcamiento sólo en OSP. En NSP se obtuvieron peores resultados que en el caso de los barbechos adyacentes. En FSP, los atributos de suelos analizados presentaron diferencias significativas con el tiempo. El contenido de humedad alcanzado a la tensión 0-300 kPa expresa la importancia de la práctica de la inundación y del establecimiento de lomos en la delimitación de las parcelas. Entre 2001 y 2009, la producción de arroz en OSP fue 5 veces mayor que en NSP. Entre 2007 y 2009, cuando los tres sistemas coexistieron, la producción de grano fue 5,80, 4,80 y 1,10 Mg ha-1 en OSP, FSP y NSP, respectivamente. En 2007 la producción fue OSP menos FSP>NSP. Sin embargo, en 2008/2009 resultó al contrario. Estos resultados ponen de manifiesto las ventajas agronómicas del sawah en la producción de arroz.

This paper examined the incidence of replacement adoption through varietal substitution among farmers adopting Sawah-ecotechnology rice production technology in Nigeria and Ghana. A simple random sampling was used to select 80 farmers in Nigeria and 70 farmers in Ghana. Data were collected in June 2010 with a structured questionnaire in villages where Sawah rice production technology had been introduced. In Nigeria, 30 % of the farmers practice varietal substitution with the use of WITA 3, while in Ghana 40% practice varietal substitution using jasmine and sycamore. The results from the Probit model showed that significant variables include yield (t = 4.12) participation in on farm demonstration (t = 2.77) contact with Sawah agent (t = -1.93), varietal adaptability (t = -2.29), market price (t = 2.50), lodging proneness (t = 2.45), age (t = -3.35) and farming experience (t = 2.49) in Nigeria and Ghana. It therefore implies that the issues of varietal substitution must be viewed within the prevailing socio-economic and farming system milieu of farmers in order to enhance continuous adoption and sustained profit from Sawah technology.S.Afr. Tydskr. Landbouvoorl./S. Afr. J. Agric. Ext., Vol. 39 Nr 2, 2011: 79 – 90

平成21年度宇宙輸送シンポジウム(2010年1月14日-15日, 宇宙航空研究開発機構宇宙科学研究本部), Space Transportation Symposium (January 14-15, 2010. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency(JAXA)), Sagamihara, Kanagawa Japan, 形態: カラー図版あり, 形態: CD-ROM1枚, Physical characteristics: Original contains color illustrations, Note: One CD-ROM, 資料番号: AA0064741101

The “sawah” technology (bunded and leveled irrigated rice field) was introduced to some farmers within the forest agro-ecology of Ghana. To improve the productivity of their soils and also to minimize expenditure on mineral fertilizers, the effect of three organic amendments on rice yield was evaluated. Poultry manure, cattle manure and rice husk were used either solely or in combination with mineral fertilizer on rice at three different locations within the forest agro-ecological zone at Potrikrom, Biemso No. 1 and Biemso No. 2. Sole organic amendments were applied at a rate of 7.0 t ha-1 and sole mineral fertilizer was applied as N-P-K at 90-60-60 kg ha-1. The N source was either urea or sulphate of ammonia, P source was triple super phosphate and K source was muriate of potash. Combinations were half rate (organic amendments + mineral fertilizer). Results showed that organic amendments, mineral fertilizer and their combinations significantly contributed to the growth and grain yield of rice. A combination of poultry manure (half rate) and mineral fertilizer (half rate) gave significantly greater grain yield than all the treatments except mineral fertilizer (full rate) at two out of the three locations. Rice grain yields were 6.2, 7.3 and 3.7 t ha-1 for half rate poultry manure + half rate mineral fertilizer at Potrikrom, Biemso No. 1 and Biemso No. 2 respectively, while full rate mineral fertilizer gave 6.6, 7.3 and 3.9 t ha-1 at the three sites respectively. In addition, a combination of organic amendments with mineral fertilizer out-yielded sole organic amendments at all the three sites. Organic amendments applied solely performed in the order: poultry manure > cattle manure > rice husk. Keywords: agro-ecology, forest, organic amendments, “sawah”, sustainability Agricultural and Food Science Journal of Ghana Vol. 3 2004: 237-248