Comportamiento de cinco poblaciones de maiz y de sus respectivos hibridos interpoblacionales en suelos fertiles y acidos.

El objetivo del presente trabajo fue verificar el comportamiento de cinco poblaciones de maiz (Zea mays L.), selecionados en condiciones de suelo cerrado no corregido (acido) (CMS 36 y CMS 30) y en suelo de cerrado corregido (CMS 14, CMS 04 y CMS 13), sus cruzamientos y cuatro hibridos comerciais en dos ambientes: suelo acido y fertil. Los utilizados en este estudio fueron, peso de mazorca (PE), altura de planta (AP), altura de mazorca (AE) y dias a la floracion masculina (DFM). Todos los caracteres fueron afectados por el tipo de ambiente. Para PE las poblaciones CMS 36 y CMS 30, presentaron buen despeno en suelo acido mas no en suelo fertil y las poblaciones CMS 04, CMS 14 y CMS 13 fueron mejores en suelo fertil. El hibrido CMS 36 x CMS 30 fue el mejor en suelo acido y el CMS 14 x CMS 36 fue el mejor en suelo fertil. La poblacion CMS 36 fue superior a los cuatro hibridos comerciales en suelo acido. El analisis conjunto de variancia nostro efectos altamente significativos (P < 0,001) para localidades (PE, AP, AE y DFM), poblacion (AP y AE) Y localidad x poblacion (PE); y significativos (P < 0,05) para cultivares (PE, AP y AE), poblaciones (PE y DFM), heterosis media (PE, DFM), y localidad por cultivar (PE), localidad x poblacion (dfm). Para el caracter PE la mayor estimacion de los efectos de localidades por heterosis de poblacion fue de la CMS 36 en suelo fertil y en suelo acido fue la CMS 04. Los hibridos CMS 30 x CMS 13 Y cms 36 X CMS 30 presentaron el mayor y menor efecto de localidad por heterosis especifica para suelo fertil y acido, respectivamente. para eterosis de poblacion la CMS 30 presento el mayor efecto, en tanto que la CMS 04 presento el menor. mayores efectos pra heterosis especifica fueron detectados para los hibridos CMS 30 x CMS 13 y CMS 13 X cms 36

DIVERSITY AND HABITAT PROFILE OF THE SHALLOW WATER HOLOTHURIANS IN CAMOTES ISLANDS, CENTRAL PHILIPPINES

Species diversity and habitat profile of holothurians in Camotes Islands, Cebu Philippines were studied as baseline data for resource and ecological management. A 150 meter transect was laid in sandy, muddy and rocky substrates of the coastal barangays during the day and night assessments of the four municipalities of Camotes Islands which are San Francisco, Poro, Tudela and Pilar. Physico-chemical instruments and interview guide to the gleaners were used to gather data. Actual collection of specimen and other data was done in every 10 meter distance in the transect where a 1m quadrat was used. Results show that there are 20 species of holothurians belonging to 3 families namely Holothuriidae, Stichopodidae and Synaptidae. There are 2 species found in sandy substrate; 10 in muddy substrate; 2 in pure rocky substrate and 6 found in both rocky and muddy substrates. Results further show that there are 13 common species of Holothurians found in the four municipalities. The most diverse municipality is San Francisco which has 18 species followed by Poro (15); Pilar (14) and Tudela (13). For the distinct species, Holothuria rigida is found only in San Francisco followed by Pearsonothuria graffei (in Tudela and Pilar); Physico-chemical parameters like salinity, range from 23-38 ppt; temperature is 260C-350C, pH 4.5-8.0 both day and night assessments. Substrate grain size analysis shows that 100 microns dominate the amount of substrates in all the barangays, followed by 200 microns and then 400 microns. Keywords: Diversity, Habitat Profile, Holothurians, Camotes Island

GEOSPATIAL ANALYSIS OF PEDIATRIC TUBERCULOSIS IN BOHOL, PHILIPPINES: DISEASE CLUSTERS AND ACCESS TO CARE

Worldwide, children represent approximately 10% of global tuberculosis (TB) cases. We recently reported a high tuberculin skin test (TST)-positive prevalence (355/5,476; weighted prevalence=6.4%) among children (\u3c15 years) throughout the island of Bohol, Philippines, with some geographically isolated communities having prevalence as high as 29%. In this study, we conducted a secondary geospatial and hot-spot analysis of this household-based cluster survey to assess the association between access to care (distance to a health care facility) and TST-positive prevalence. Our analysis indicated that villages with high TST-positive prevalence (≥10%) were significantly further from Provincial Health Office based in the capital city of Tagbilaran in time-distance (p=0.0001, r=0.2387) and kilometers (p=0.0011, r=0.3170). Similarly, prevalence was positively correlated with distance to the municipal Rural Health Unit (RHU), where most receive their medical care, in time-distance (p=0.0055; r=0.0415); however, the association was not significant in kilometers (p=0.3315; r=0.0715). Distance to health care facilities could represent an obstacle to access to care, thereby limiting diagnosis and treatment and resulting in increased risk of transmission to others in the community. Health care outreach in geographically isolated areas is critical to treatment and control of efforts for pediatric TB

Learning about migration decisions from the migrants : an exercise in endogenous sampling and complementary datasets

Se investigan los determinantes del importante aumento de las migraciones intrarregionales en España desde los años ochenta, utilizando la Estadistica de Variaciones Residenciales. Se identifican las probabilidades de migracion condicionales comparando la distribucion conjunta de caracteristicas de los migrantes con la distribucion correspondiente a la poblacion total de migrantes y no migrantes, utilizando para ello la Encuesta de Poblacion Activa. La proporcion de empleo en el sector servicios, los precios de la vivienda y la educacion tienen un importante efecto positivo sobre las probabilidades de migracion intrarregionales individuales. (ob) (ad

Changes in the size structure of the yellowfin tuna population of the tropical eastern Pacific Ocean from 1947 to 1955

ENGLISH: Morphometric studies by Godsil (1948), Godsil and Greenhood (1951), Royce (1953) and Schaefer (1952, 1955) have indicated that the yellowfin tuna of the Eastern Pacific are distinct from those of the Central Pacific. Tagging of yellowfin tuna by the California Department of Fish and Game, and by the Inter-American Tropical Tuna Commission in the Eastern Pacific, and by the Pacific Oceanic Fishery Investigations in the Central Pacific, have not yet revealed any migrations between these areas. Shimada and Schaefer (1956) have compared changes in population abundance and fishing intensity, considering the population in the Eastern Pacific as a separate entity. They conclude " ... the amount of fishing has had a real effect upon the stock of Eastern Pacific yellowfin tuna, taken in the aggregate, over the period studied. The evidence suggests also that for this species the intensity of fishing in some recent years has reached and might have even exceeded the level corresponding to the maximum equilibrium yield." Tagging experiments by the California Department of Fish and Game and by the Inter-American Tropical Tuna Commission have yielded returns in the order of one to five percent (Roedel 1954, and unpublished data of both agencies), a level much lower than that at which fishing intensity would be expected to noticeably affect the population size. These results are probably a reflection of the inadequacies of the present tagging methods, but they could lend doubt to the conclusions of Shimada and Schaefer. It is desirable, therefore, to examine other, independent, evidence as to the effects of fishing on the population. At the high levels of fishing intensity suggested by Shimada and Schaefer, in addition to changes in quantity, measurable changes would be expected to have occurred in the quality of the yellowfin tuna stocks, because the average age and size of the fish would have been reduced by the high mortality rates accompanying high fishing intensities. A continuing regular program of sampling catches and determining their length composition, to assess changes in the size composition of the stocks, was initiated by the Commission in 1954 but direct measurements are not available for the earlier, more dynamic period of growth of the fishery. Consequently, other, more general indications of possible changes in the size composition were sought. SPANISH: Los estudios morfométricos efectudos por Godsil (1948), Godsil y Greenhood (1951), Royce (1953) y Schaefer (1952, 1955), han demostrado que el atún aleta amarilla del Pacífico Oriental es distinto del que habita el PacÍfico Central. Los experimentos del Departamento de Pesca y Caza de California y de la Comisión Interamericana del Atún Tropical en el Pacífico Oriental, así como los de las Investigaciones Pesqueras del Océano Pacífico en el Pacífico Central,consistentes en la marcación de atunes aleta amarilla, aún no han puesto de manifiesto movimientos migratorios entre dichas áreas. Shimada y Schaefer (1956) han hecho estudios comparativos sobre la abundancia de la población y la intensidad de la pesca, considerando a la población del Pacífico Oriental como una entidad separada. Su conclusión es que " ... la intensidad de la pesca ha tenido un definido efecto sobre la población del atún aleta amarilla del Pacífico Oriental, tomada en conjunto, a lo largo del período estudiado. La evidencia de que se dispone sugiere así mismo que, por lo que hace a esta especie, la intensidad de la pesca en los últimos años ha alcanzado y quizás aún sobrepasado el nivel correspondiente a la máxima pesca de equilibrio". Los experimentos de mar•cación del Departamento de Pesca y Caza de California y de la Comisión Interamericana del Atún Tropical han producido recuperaciones ,entre el uno y el cinco por ciento (Roedel 1954 y datos inéditos de ambos organismos), lo que constituye un nivel mucho más bajo de aquél en que la intensidad de la pesca podría considerarse que afectaría notablemente el tamaño de la población. Estos resultados reflejan probablemente lo inadecuados que son aún los métodos de marcación, pero ellos podrían, quizá, poner en tela de juicio las conclusiones de Shimada y Schaefer. Por lo tanto,es deseable examinar otras fuentes de evidencia independientes, relacionadas con el efecto que la pesca tiene sobre la población. En efecto, si los altos índices de pesca sugeridos por Shimada y Schaefer son correctos, es de esperar que, además de los cambios en la magnitud de la población, se hayan producido otros, concomitantes y sensibles, en la calidad de los stocks de atún aleta amarilla, puesto que tanto el promedio de edad como el de tamaño de los individuos habrían disminuído debido a las elevadas tasas de mortalidad inherentes a las altas intensidades de pesca. En 1954 la Comisión inició un programa ininterrumpido para tomar muestras y determinar en ellas las frecuencias de tallas y evaluar de este modo los cambios correlativos que tuvieran lugar en los stocks pero, infortunadamente, este sistema de evaluación directa no fué practicado en el período anterior, que fué precisamente el de rápida expansión de la pesquería. En tal virtud, hubo de ser necesario buscar indicios más generales referentes a los cambios posibles en la composición de tamaños. (PDF contains 20 pages.

A study of changes in fishing effort, abundance, and yield for yellowfin and skipjack tuna in the Eastern Tropical Pacific Ocean

ENGLISH: The rapid growth of the Eastern Pacific fishery for yellowfin and skipjack tuna since the end of World War II has given rise to questions concerning the rational utilization of these resources. As part of the Inter-American Tropical Tuna Commission's program of research designed to investigate these problems, a study was undertaken to determine from the historical records of the fishery the effects of fishing upon the stocks of yellowfin and skipjack tuna of the Eastern Pacific region and to evaluate the present condition of these stocks with respect to the maximum equilibrium yield. SPANISH: EI rápido crecimiento, desde la terminación de la Segunda Guerra Mundial, de la pesquería de atún aleta amarilla y barrilete en el Pacifico Oriental, ha dado lugar a que se hagan algunos comentarios sabre la racional utilización de estos recursos. Como parte del programa de la Comisión Interamericana del Atún Tropical designado para la investigación de estos problemas, un estudio fué llevado a cabo para determinar, de los informes historicós de la pesquería, los efectos de la pesca sobre los stocks de atún aleta amarilla y barrilete de la región del Pacifico Oriental y para evaluar la presente condición de estos stocks con respecto al máximo rendimiento de equilibria. (PDF contains 123 pages.

"Access to Markets and Farm Efficiency: A Study of Rice Farms in the Bicol Region, Philippines"

This paper presents an empirical investigation of the relationship between the spread, spatially and temporally, of market institutions and improvements in the productivity and efficiency of farmers. The data used in this study were collected over two decades in a sample of rice farms in the Bicol Region of the Philippines. Our estimates reveal a significant inverse relationship between distance from the market and farm productivity and efficiency in 1983. While there are substantial improvements in yields, unit costs, and efficiency in the two decades that followed, the gains are larger in the more remote and sparsely populated villages. This finding suggests that the relationship between remoteness and farm outcomes has weakened over time. We also find that the development of markets in the peripheral villages and the improved connectivity between the peripheral villages and market centers are facilitated by population growth, infrastructural investments (specifically, irrigation and roads), and the availability of agricultural extension programs.Farm Efficiency; Agricultural Markets; Institutional Conditions; Philippines

Migration and the Rural-Urban Continuum: Evidence from Bukidnon, Philippines

This paper explores the heterogeneity of the migrant experience using the Bukidnon Panel Survey, which follows up 448 families in rural Mindanao who were first interviewed in 1984-85, as well as their offspring. Migration patterns are examined using the full listing of children of the original respondents as well as a special survey including 257 of the migrant offspring who were tracked down and interviewed in 2004. The migrant survey focuses on differences in the migration experience of males and females who migrated to rural, poblacion, and urban areas. The study finds that rural areas, poblaciones, and urban areas systematically attract different types of migrants. It also finds that the most important determinants of an individual`s location decision are life-cycle effects, specifically marriage and educational attainment.migration, Bukidnon, migration decision, migration pattern

Migration and the rural-urban continuum: Evidence from the Rural Philippines

This paper explores the diversity of the experience of migrants to rural, peri–urban, and urban areas using a unique longitudinal data set from the Philippines. In 2003 and 2004, the Bukidnon Panel Study followed up with 448 families in rural Mindanao who were previously interviewed in 1984/85 by the International Food Policy Research Institute and the Research Institute for Mindanao Culture, Xavier University, and surveyed both a sample of their offspring living in the same area as well as a sample of those who had moved away to different locations. Parents (original respondents) and children who formed separate households in the same locality were interviewed in 2003; original respondents' offspring that migrated to different rural and urban areas were interviewed in 2004. Thus, migration patterns were examined using the full listing of children of the original respondents as well as a special survey of 257 of their migrant offspring who were tracked down in 2004. This migrant survey focused on differences in the migration experience of males and females who moved to other rural areas, poblaciones (the administrative seats of municipalities or towns), and urban areas. We follow this with an examination of the determinants of children's location, using the sample of all children. In addition to migration to rural, peri–urban, and urban destinations, we explicitly consider the case where the individual leaves his or her parental residence, but remains in the same village, as a locational choice." from Authors' Abstract