A new andean Liolaemus of the L. montanus series (Squamata: Iguania: Liolaemidae) from western argentina

A new species of the Iguanian genus Liolaemus, member of the montanus series, is described. The species inhabits altitudes above 4000 meters and is endemic to the Provincial Reserves of Laguna Brava, province of La Rioja, and San Guillermo, province of San Juan, areas located in the Andes mountains of Argentina. Liolaemus sp. nov. has a medium-sized body (maximum SVL = 76.9 mm) with tail subequal in length to the SVL; unkeeled, juxtaposed dorsal scales, in high number around midbody (86-106); precloacal pores in males (4-7), mostly absent in females or in very low number (up to 2 pores); head and body strongly melanic; evident sexual dichromatism, and a distinctive color pattern. Liolaemus sp. nov. lives geographically close but in allopatry to L. andinus, L. eleodori and L. vallecurensis, all species of the montanus series, morphologically alike and probably phylogenetically related to the new species.Fil: Abdala, Cristian Simón. Universidad Nacional de Tucuman. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Instituto Miguel Lillo; ArgentinaFil: Acosta, Juan Carlos. Universidad Nacional de San Juan. Facultad de Ciencias Exactas Físicas y Naturales. Departamento de Biología; ArgentinaFil: Cabrera, Mario Roberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Diversidad y Ecología Animal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto de Diversidad y Ecología Animal; ArgentinaFil: Villavicencio, Héctor J.. Universidad Nacional de San Juan. Facultad de Ciencias Exactas Físicas y Naturales. Departamento de Biología; ArgentinaFil: Marinero, Jose Alberto. Universidad Nacional de San Juan. Facultad de Ciencias Exactas Físicas y Naturales. Departamento de Biología; Argentin

Ecología trófica, dimorfismo sexual y parámetros reproductivos en el lagarto endémico Andino Liolaemus vallecurensis, Argentina

RESUMEN Se evaluaron los hábitos alimenticios, dimorfismo sexual y parámetros reproductivos en Liolaemus vallecurensis (Pereyra, 1992) en un sector Andino de Argentina. Para examinar la dieta, se determinó volumen, numerosidad y frecuencia de ocurrencia para cada ítem-presa y se calculó el Índice de Importancia Relativa (IRI). Además se aplicaron índices tróficos (Levins) e índices de diversidad. Se estudiaron las variaciones morfológicas en 14 medidas comparando machos y hembras adultos. Considerando los artrópodos, L. vallecurensis consume principalmente ítem del orden Hymenoptera (no Formicidae) no encontrándose diferencias tróficas entre sexos ni por edades. Los machos presentan tendencia hacia una estrategia de búsqueda activa y una dieta especialista. Las hembras y juveniles cazan al acecho con una dieta de tipo más oportunista. Los machos consumen grandes cantidades de materia vegetal considerándose como herbívoros aunque no estrictamente, hembras omnívoras y juveniles entre insectívoros y omnívoros. Se encontró dimorfismo entre sexos en 10 variables morfológicas. Se encontró asociación entre la longitud de cabeza y el modo de búsqueda de alimento. Se confirma la condición vivípara con un tamaño de camada de tres crías, con una parición entre fines de diciembre y principios de enero. Estos aportes en L. vallecurensis representan los primeros y únicos datos biológicos para esta especie en estos ambientes rigurosos

Clinical characterization of data-driven diabetes subgroups in Mexicans using a reproducible machine learning approach

Introduction Previous reports in European populations demonstrated the existence of five data-driven adult-onset diabetes subgroups. Here, we use self-normalizing neural networks (SNNN) to improve reproducibility of these data-driven diabetes subgroups in Mexican cohorts to extend its application to more diverse settings.Research design and methods We trained SNNN and compared it with k-means clustering to classify diabetes subgroups in a multiethnic and representative population-based National Health and Nutrition Examination Survey (NHANES) datasets with all available measures (training sample: NHANES-III, n=1132; validation sample: NHANES 1999–2006, n=626). SNNN models were then applied to four Mexican cohorts (SIGMA-UIEM, n=1521; Metabolic Syndrome cohort, n=6144; ENSANUT 2016, n=614 and CAIPaDi, n=1608) to characterize diabetes subgroups in Mexicans according to treatment response, risk for chronic complications and risk factors for the incidence of each subgroup.Results SNNN yielded four reproducible clinical profiles (obesity related, insulin deficient, insulin resistant, age related) in NHANES and Mexican cohorts even without C-peptide measurements. We observed in a population-based survey a high prevalence of the insulin-deficient form (41.25%, 95% CI 41.02% to 41.48%), followed by obesity-related (33.60%, 95% CI 33.40% to 33.79%), age-related (14.72%, 95% CI 14.63% to 14.82%) and severe insulin-resistant groups. A significant association was found between the SLC16A11 diabetes risk variant and the obesity-related subgroup (OR 1.42, 95% CI 1.10 to 1.83, p=0.008). Among incident cases, we observed a greater incidence of mild obesity-related diabetes (n=149, 45.0%). In a diabetes outpatient clinic cohort, we observed increased 1-year risk (HR 1.59, 95% CI 1.01 to 2.51) and 2-year risk (HR 1.94, 95% CI 1.13 to 3.31) for incident retinopathy in the insulin-deficient group and decreased 2-year diabetic retinopathy risk for the obesity-related subgroup (HR 0.49, 95% CI 0.27 to 0.89).Conclusions Diabetes subgroup phenotypes are reproducible using SNNN; our algorithm is available as web-based tool. Application of these models allowed for better characterization of diabetes subgroups and risk factors in Mexicans that could have clinical applications