Erythropoietin (Epo) is a glycoprotein hormone that regulates erythroid development and interacts with surface receptors' n developing erythroid cells. In this laboratory, a cell system with a relatively pure population of erythroid cells that respond to Epo has been developed. Immature erythroid cells are obtained from the spleens of mice infected with the anemia strain of Friend virus. The binding of

Thirty-six Native American tribal leaders and members living on contiguous rural Southwest California reservations were surveyed concerning their view of the acceptability of a Motivational Interviewing (MI) intervention to youth (ages 8-18 years) who are drinking and their families. The results suggest that: (1) a substantial proportion of reservation youth would be willing to accept MI for behavior change; (2) relatively few are actually ready to change; (3) most reservation youth are in the pre-contemplation stage of change; and (4) MI may be well suited as an intervention to prevent underage drinking in that population. Supported by NIH.

SUMMARYThe studies on reconstruction of paleoclimatic series play an important role in analyzing regional climate variability when instrumental information is not available. Tree-ring samples from stands of Pinus durangensis, Pinus cooperi and Pinus lumholtzii were used to generate chronologies in order to reconstruct and analyze the historical hydroclimatic variability for the region of San Dimas, Durango, Mexico. A principal component analysis (PCA) indicates that those series showed a common variability; subsequently, a regional series was developed covering a period of 294 years. An analysis of response function suggests that the most important climate variable influencing tree growth was the seasonal winter-spring precipitation (January-June), which accounted for 52 % of the variability. Reconstruction of the variability of the winter-spring precipitation for the last three centuries was possible. Such a profile allowed us to identify important drought periods (1740-1746, 1766-1780, 1785-1786, 1819-1824, 1890-1900, 1935-1940, 1950-1957 and 2011-2015). Because of their extension, the periods 1766-1780, 1890-1900 and 1950-1957 were the longest. Based on historical records, four events of severe drought (1785-1786, 1935-1940, 1891-1902 and 1950) were associated with strong havoc in central Mexico and their effects were extended to northern Mexico. In addition, a wavelet coherence analysis suggests a strong relationship between the reconstructed precipitation (Winter-Spring) and NIÑO 3 SST (December to February) in phase from 1770 to 1978 with frequencies from 1 to 5 years, ENSO has significantly modulated climate variability in this region of the state of Durango.Key words: chronologies, reconstructed precipitation, drought, ENSO. RESUMENLos estudios de reconstrucción de series paleoclimáticas juegan un papel importante para analizar la variabilidad del clima regional cuando no se dispone de información instrumental. Muestras de anillos de árboles de rodales de Pinus durangensis, Pinus cooperi y Pinus lumholtzii fueron empleados para generar cronologías con el objetivo de reconstruir y analizar la variabilidad hidroclimática histórica para la región de San Dimas, Durango, México. Un análisis de componentes principales (PCA) determinó que las series presentan variabilidad común, se desarrolló una serie regional de 294 años. Un análisis de función de respuesta mostró que la variable climática que más ha influido en el crecimiento es la precipitación estacional invierno-primavera (enero-junio), que explicó el 52 % de la variabilidad. Se logró reconstruir la lluvia invierno-primavera para los últimos tres siglos. Esta reconstrucción permitió identificar importantes periodos de sequía (1740-1746, 1766-1780, 1785-1786, 1819-1824, 1890-1900, 1935-1940, 1950-1957 y 2011-2015), por su extensión destacaron los periodos 1766-1780, 1890-1900 y 1950-1957. Con base en archivos históricos, se corroboraron cuatro eventos de sequía severa (1785-1786, 1935-1940, 1891-1902 y la década de 1950) que propiciaron fuertes estrago...

ResumenLa presencia de especies vegetales está en función de la altitud, por lo que, el propósito de este estudio fue estimar y comparar la diversidad arbórea sobre un gradiente altitudinal entre los 1 500 a los 3 000 m de la región de El Salto, Durango, que fue dividido en cinco intervalos de 300 m cada uno. Se seleccionaron doce comunidades forestales, y se ubicaron 268 sitios circulares de 0.1 ha de manera aleatoria, distribuidos de forma proporcional por cada intervalo, dentro del cual se estimó la riqueza de especies (S), los índices de diversidad proporcional de Shannon-Wiener (H') y Simpson (l), los de equidad de Pielou (J') y de dominancia de Simpson (E l ). La comparación de la diversidad arbórea entre altitudes se hizo sobre el índice de Shannon-Wiener mediante la prueba de t de Hutcheson. La riqueza de especies varió de 14 a 25 taxa, el índice de Shannon de 1.94 a 2.67 y el de Simpson de 0.09 a 0.18. Los de equidad y dominancia de Pielou y Simpson sugieren que la abundancia de las especies tiende a ser heterogénea. La prueba de t de Hutcheson demostró que existen diferencias significativas en la diversidad de especies entre los intervalos altitudinales.Palabras clave: Diversidad arbórea, gradiente altitudinal, índice de Pielou, índice de Shannon-Wiener, índice de Simpson, riqueza de especies. AbstractThe presence of plant species is a function of altitude; therefore, the purpose of this study was to estimate and compare tree diversity on the altitudinal gradient of the El Salto, Durango region. Twelve forest communities were selected from between 1 500 and 3 000 m, which was divided into five intervals of 300 m each. A total of 268 circular sites of 0.1 ha were randomly distributed proportionally for each interval, where species richness (S), proportional diversity indexes of Shannon-Wiener (H') and Simpson (l), of Pielou's equity (J') and dominance of Simpson (E l ) were determined. Comparison of tree diversity between altitudes was made on the Shannon-Wiener index using the Hutcheson t-test. Species richness varied from 14 to 25 taxa, the Shannon-Wiener index from 1.94 to 2.67 and Simpson's 0.09 to 0.18. Equity and dominance by Pielou and Simpson suggest that species abundance tends to be heterogeneous. The Hutcheson t test showed that there are significant differences in species diversity between altitudinal intervals.

Underage drinking is an important public health issue for American Indian and Alaska Native (AI/AN) adolescents, as it is for U. S. teens of all ethnicities. One of the demonstrated risk factors for the development of alcohol use disorders in AI/AN is early age of initiation of drinking. To address this issue a randomized trial to assess the efficacy of Motivational Interviewing (MI) compared to Psycho-Education (PE) to reduce and prevent underage drinking in AI/AN youth was developed and implemented. Sixty-nine youth received MI or PE and 87% were assessed at follow-up. For teens who were already drinking, participating in the intervention (MI or PE) was associated, at follow-up, with lower quantity × frequency (qxf) of drinking (p=0.011), fewer maximum drinks per drinking occasion (p=0.004), and fewer problem behaviors (p=0.009). The MI intervention resulted in male drinkers reporting a lower qxf of drinking (p=0.048) and female drinkers reporting less depression (p=0.011). In teens who had not started drinking prior to the intervention, 17% had initiated drinking at follow-up. As a group they reported increased quantity × frequency of drinking (p=0.008) and maximum drinks (p=0.047), but no change in problem behaviors. These results suggest that intervening against underage drinking using either MI or PE in AI/AN youth can result in reduced drinking, prevention of initiation of drinking, and other positive behavioral outcomes. Brief interventions that enhance motivation to change as well as psycho-education may provide a successful approach to reducing the potential morbidity of underage drinking in this high-risk group.