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El cambio climático y el Antropoceno plantean numerosos desafíos para todos los sectores de la sociedad. Desde la antropología, uno de ellos es cómo utilizar el profundo conocimiento situado sobre las relaciones humano-ambiente para la adaptación al cambio ambiental acelerado, en especial de las comunidades de frontera que son a la vez el objeto de estudio tradicional de la disciplina y las principales afectadas por el deterioro ambiental. Se presenta entonces la construcción de nicho como una forma holística de integrar estos conocimientos y se describe el ejemplo del Gran Chaco. Para ello se discuten tanto prácticas pasadas de domesticación del paisaje, como las principales modificaciones actuales, y se analiza una problemática socioambiental reciente: la inundación de la comunidad toba de Sombrero Negro en 2018. Por último, se describen proyecciones climáticas para el área y se hace una reflexión sobre el rol de la antropología biológica para la vida en el Antropoceno., Climate change and the Anthropocene pose numerous challenges for all sectors of humanity. For anthropology, one of them is how to use the deep situated knowledge on human-environment relations for adaptation to accelerated environmental change, especially in frontier communities that are both the traditional object of study of the discipline and the main affected by environmental deterioration. Niche construction is then presented as a holistic way of integrating this knowledge and the example of the Gran Chaco is described. To this end, both past practices of landscape domestication and the main current modifications are discussed, and a recent socio-environmental problem is analyzed: the flooding of the Toba community of Sombrero Negro in 2018. Finally, we describe climate projections for the area and call for a biological anthropology that is useful for living in the Anthropocene., As alterações climáticas e o Antropoceno representam inúmeros desafios para todos os sectores da humanidade. Para a antropologia, um deles é como utilizar o profundo conhecimento situado sobre as relações homem-ambiente para a adaptação às mudanças ambientais aceleradas, especialmente nas comunidades fronteiriças que são simultaneamente o objeto tradicional de estudo da disciplina e o principal afetado pela deterioração ambiental. A construção de nicho é então apresentada como uma forma holística de integrar estes conhecimentos e é descrito o exemplo do Gran Chaco. Para tal, são discutidas tanto as práticas passadas de domesticação da paisagem como as principais modificações atuais, e é analisado um problema sócio-ambiental recente: a inundação da comunidade Toba de Sombrero Negro em 2018. Finalmente, descrevemos projeções climáticas para a área e apelamos a uma antropologia biológica que seja útil para viver no Antropoceno., Facultad de Ciencias Naturales y Museo

Prevalence of the metabolic syndrome (MetS) is high in the United States and is associated with increased risk of cardiovascular disease and diabetes. The authors examined whether the prevalence of the MetS and its components differs across age groups. Data were analyzed from 4 National Health and Nutrition Examination Surveys between the years 1999 and 2006. Prevalence of MetS as defined by the Third Report of the Adult Treatment Panel criteria and prevalence of associated cardiac risk factors were determined in 41,474 participants aged 18 years and older without a history of cardiovascular disease (CVD). All estimates were weighted. Prevalence of MetS among asymptomatic adults without CVD was 20.5% and remained stable for the total population during survey periods. Prevalence of MetS increased with age: 6.6% in young adults (age 18-29 years) and 34.6% in older adults (70 and older). Components of MetS differed between young and old adults. Young adults had lower levels of high-density lipoprotein cholesterol, less glucose intolerance, and less hypertension. This study provides an estimate of MetS prevalence in asymptomatic adults in the United States during an 8-year period revealing that MetS affects a large number of Americans. Components of MetS differ between young and old adults and may have important implications in their clinical management.

Most studies on craniofacial morphology have focused on adult individuals, but patterns of variation are the outcome of genetic and epigenetic variables that interact throughout ontogeny. Among cranial regions, the orbits exhibit morphological variation and occupy an intermediate position between neurocranial and facial structures. The main objective of this work was to analyze postnatal ontogenetic variation and covariation in the morphology of the orbital region in a cross-sectional series of humans from 0 to 31 years old. Landmarks and semilandmarks were digitized on the orbital rim, as well as in neighboring neural and facial structures. Data were analyzed using geometric morphometrics. Results indicated that orbital size increases during the first years of postnatal life, while the shape of the orbital aperture does not change significantly with age. In general, the pattern and magnitude of shape covariation do not vary markedly during postnatal life although some subtle shifts were documented. Additionally, the shape of the orbital aperture is more related to the anterior neurocranium than to zygomatic structures, even when the allometry is adjusted. Although we expected some influence from postnatal craniofacial growth and from some functional factors, such as mastication, on the development of the orbits, this assumption was not completely supported by our results. As a whole, our findings are in line with the prediction of an early influence of the eyes and extraocular tissues on orbital morphology, and could be interpreted in relation to processes promoting early neural development that coordinately affects orbital traits and the neurocranial skeleton.

Desde hace algunas décadas, el Museo de La Plata (Universidad Nacional de La Plata, Argentina) ha recibido reclamos por parte de comunidades aborígenes que solicitan la restitución de restos humanos, así como su retiro de las salas de exhibición. Conjuntamente con la aparición de normativas que reconocen derechos en los pueblos originarios y el debate de la propia comunidad académica, se ha desarrollado en los últimos años una política integral en relación con el manejo de restos humanos dentro de la institución. El objetivo de este trabajo es presentar los acontecimientos, debates y decisiones acerca de la modalidad de exhibición de restos humanos en el Museo de La Plata. El principal cambio se produjo en 2006, cuando se decidió retirar de exhibición las momias y partes esqueletarias de poblaciones aborígenes de América y, paralelamente, la elaboración de mensajes a los visitantes según estas decisiones políticas. El nuevo guión de la exposición gira en torno a la evolución humana, contemplando la inclusión de un sector especialmente dedicado a la reflexión sobre el significado de prácticas y representaciones sobre la muerte y los muertos, el valor del estudio científico sobre este tipo de evidencias y los derechos de las comunidades sobre sus muertos. Palabras clave: política; comunidades aborígenes; visitantes; museo Since some decades, aboriginal communities have been demanding to the Museo de La Plata that human remains be restored to the communities they belong to and removed from public exhibition. Regulations that recognize the rights of indigenous people, together with debates within the academic community, have contributed to the development of institutional policies on the treatment and care of human remains. The goal of this work is to present the events, debates and decisions related to the modes of exhibition of human remains in the Museum de La Plata. The main shift occurred in 2006 when it was decided that all mummies and skeletal parts belonging to American aborigines must be removed from exhibition. It was also considered necessary that the institution put up messages conveying these political decisions to visitors. The curation of the new exhibition is based on human evolution and includes a sector devoted to reflection on the meaning of the practices and representations about death and the dead, the scientific value of the study of human remains, and the rights of the communities to claim bodies. Keywords: policies; aboriginal communities; visitors; museum

Diversos estudios proponen que el neurocráneo en Homo sapiens es una estructura integrada y que la morfología de la bóveda y la base se asocia con modificaciones del cerebro. En este estudio se evaluó la covariación ontogénica en el endocráneo de Pan troglodytes, otro primate altamente encefalizado. Se analizaron 52 reconstrucciones 3D derivadas de tomografías computadas de individuos adultos y subadultos. Una vez segmentadas las cavidades endocraneanas, se relevaron 27 landmarks. A partir de su configuración, se obtuvieron el tamaño del centroide y las coordenadas de Procrustes y se realizó Análisis de Componentes Principales, regresión, correlación, ANOVA y análisis F de Goodall a fin de evaluar los cambios de tamaño y forma respecto de la edad y las alometrías. Los cambios en forma están fuertemente integrados y se producen hasta etapas tardías de la ontogenia: elongación de la bóveda y la base, distanciamiento entre el foramen magnun y la placa cribiforme, retroflexión del ángulo basicraneano y descenso de los polos temporales. A partir del análisis PLS se observó que los cambios en la base y la bóveda covarían, pero cuando se ajustó el efecto alométrico, dicha covariación se hizo no significativa, tal como ocurre en Homo sapiens. Esto sugiere que el aumento ontogénico del volumen endocraneano -en relación con el crecimiento cerebral- constituye un factor común de integración entre la bóveda y la base en ambas especies. Sin embargo, es probable que en el chimpancé se sume la influencia de distintas estructuras faciales que promuevan variación y covariación en el endocráneo., Several studies propose that the neurocranium in Homo sapiens is an integrated structure, being the growing brain the factor that influences the vault and the base morphology. The goal of this study is to assess endocranial ontogenetic covariation in Pan troglodytes, another encephalized primate. Fifty-two 3D reconstructions derived from computed tomographies of adult and subadult specimens were analyzed. After segmentation of the endocranial volumes, twenty-seven landmarks were registered. Through their configuration, centroid size and Procrustes coordinates were obtained, and Principal Components Analysis, regression, correlation, ANOVA and Goodall’s F-test were performed in order to evaluate size and shape changes against age and allometries. The results indicated that significant morphological ontogenetic shape changes are highly integrated and they occur up to the late ontogeny: elongation of the vault and the base, separation of the foramen magnum and the cribiform plate, retroflection of the basicranial angle, and descent of the temporal poles. By means of PLS analysis, a significant covariation between the vault and the base was obtained. However, when the allometric effect was adjusted, the covariation became non-significant, as occurs in Homo sapiens. This suggests that the ontogenetic increase in the endocranial volume —related to the growing brain— may be a common integrative factor between the vault and the base in both species. Nonetheless, different facial structures are also likely to promote variation and covariation in the chimpanzee’s endocranium., Asociación de Antropología Biológica de la República Argentina (AABRA)

This work assesses cranial vault thickness (CVT) ontogenetic changes using a computed tomography database to register thickness across multiple regions.Vault images of 143 individuals from 0 to 31 years old were analyzed by thickness semiautomatic measurements. For each individual, we obtained a thickness mean measure (TMM) and its coefficient of variation, a measure of endocranial volume (EV), the distribution of relative frequencies of thickness-relative frequency polygon, and a topographic mapping that shows the thickness arrangement through a chromatic scale. Ontogenetic changes of these variables were evaluated by different regression models (TMM vs. age, EV vs. age, TMM vs. EV) and visual comparisons between the age groups.TMM increased during ontogeny until the onset of adulthood without sex differences, but the most accelerated growth rates occur during the first 6 years of postnatal life. TMM variations were associated with EV only in infants and children, but not in later periods. The polygons showed a flattening during ontogeny, probably due to an increase in thickness variation within individuals. However, the adult pattern of thickness arrangement, with the lateral region thinner than the regions near sagittal plane, was detected from infancy.The pattern of thickness arrangement is established early in ontogeny but CVT increases and changes in distribution until adolescence. Several factors may influence CVT, such as the brain, muscles, vessels, and sutures.

J Clin Hypertens (Greenwich). 2012;00:00–00. ©2012 Wiley Periodicals, Inc. Prevalence of the metabolic syndrome (MetS) is high in the United States and is associated with increased risk of cardiovascular disease and diabetes. The authors examined whether the prevalence of the MetS and its components differs across age groups. Data were analyzed from 4 National Health and Nutrition Examination Surveys between the years 1999 and 2006. Prevalence of MetS as defined by the Third Report of the Adult Treatment Panel criteria and prevalence of associated cardiac risk factors were determined in 41,474 participants aged 18 years and older without a history of cardiovascular disease (CVD). All estimates were weighted. Prevalence of MetS among asymptomatic adults without CVD was 20.5% and remained stable for the total population during survey periods. Prevalence of MetS increased with age: 6.6% in young adults (age 18–29 years) and 34.6% in older adults (70 and older). Components of MetS differed between young and old adults. Young adults had lower levels of high‐density lipoprotein cholesterol, less glucose intolerance, and less hypertension. This study provides an estimate of MetS prevalence in asymptomatic adults in the United States during an 8‐year period revealing that MetS affects a large number of Americans. Components of MetS differ between young and old adults and may have important implications in their clinical management.

The skull is considered a modular structure in which different parts are influenced by different factors and, as a result, achieve adult shape at different ages. Previous studies have suggested that the basicranium presents a modular pattern that distinguishes sagittal and lateral parts, probably affected by the brain and masticatory structures, respectively. The vault of modern humans, in contrast, has been considered as a highly integrated system mainly influenced by brain growth. Here, we explored developmental shape variation in sagittal and lateral ectocranial vault in humans in order to assess if both regions are ontogenetically dissociated. We used a sample of 135 cranial computed tomography images from 0 to 31 ages. Landmarks and semilandmarks were collected on sagittal and lateral regions and geometric morphometric techniques were applied separately for each region. On the shape coordinates, we used Goodall's F-test in order to assess the age when the adult configuration is attained. Principal component analysis enabled us to evaluate shape variation during ontogeny. Results indicated that both sagittal and lateral structures attain adult shape at early adolescence. Both regions express coordinated shape modifications probably due to shared developmental factors. It is concluded that masticatory muscles may not exert a strong enough influence to produce independent variation in the lateral traits. Thus, it is likely that the brain integrates sagittal and lateral parts of the vault across human ontogeny.

RESUMEN El dimorfismo sexual facial (DSF) involucra variación en tamaño y forma. Es aceptado que la variación en forma se asocia al tamaño (alometría) y que durante la ontogenia ambos sexos comparten las mismas alometrías y los hombres extienden la trayectoria alométrica, proceso conocido como escalamiento ontogénico. Aquí se analiza el DSF en dos muestras ontogénicas de humanos modernos -portugueses (muestra Coimbra) y africanos de origen bantú (muestra Dart)- para conocer si los sexos comparten trayectorias alométricas. Se relevaron 12 mediciones lineales de la cara. Previo cálculo de la media geométrica (MG) para estimar el tamaño, se estandarizaron para evaluar forma. Para cada muestra se realizó Análisis de Componentes Principales. Por Análisis Multivariado y Univariado dela Covarianza se evaluaron las trayectorias alométricas. Ambos métodos mostraron trayectorias no comunes entre los sexos para ambas muestras. Los primeros indicaron trayectorias diferentes en pendientes para Coimbra, mientras que en Dart las pendientes fueron homogéneas, aunque no la intersección. Los análisis univariados, sin embargo, indicaron que en ambas muestras las trayectorias no difieren en sus pendientes entre los sexos pero si en su intersección para el componente principal 1, siendo paralelas, por lo que habría diferencias sexuales con probable origen prenatal. Otro mecanismo involucra una extensión de la trayectoria masculina con respecto de la femenina. El escalamiento ontogénico también generaría diferencias sexuales. El grado de DSF en tamaño es mayor en Coimbra que en Dart. Dichas diferencias pueden deberse a variaciones poblacionales en los mecanismos de crecimiento y desarrollo. ABSTRACT Facial sexual dimorphism (FSD) involves facial variation in size and shape. It is accepted that the shape variation is associated with size (allometry) that during ontogeny both sexes share the same allometric trajectory, and men lengthen the allometric trajectory, process known as ontogenetic scaling. In this work FSD was analyzed in two ontogenetic modern human samples -Portuguese (Coimbra) and Africans of Bantu origins (Dart)- in order to know if both sexes share the allometric trajectories. Twelve linear measurements were registered on the face. The geometric mean was calculated and measurements were standardized in order to evaluate shape variation. Principal component analysis was performed in each sample. In order to assess if allometric trajectories differ between males and females multivariate and univariate analyses of covariance were performed. Both methods showed no common trajectories between both sexes. In the multivariate analyses Coimbra sample trajectories differs in their slopes, while in Dart sample trajectories are homogeneous in slopes but not in their intercept. However, univariate results indicated that in both samples allometric trajectories do not differ in their slopes between sexes and they are parallel for principal component 1; this may be the consequence of differentiation with probable prenatal origins. Another mechanism involves the lengthening of the male trajectory regarding females. Ontogenetic scaling would generate differences between sexes in both samples. However, the degree of FSD in size is greater inCoimbra than in Dart sample. This difference may be explained by population variation in the mechanism of growth and development. Publicado on-line:20-08-2012

This study aimed to compare percutaneous coronary intervention (PCI) with direct stenting (DS) to balloon predilatation (PD) for patients undergoing elective PCI to determine whether there is an independent value for DS with regard to clinical outcomes.The safety of PCI with DS has been established, but the independent advantages of this technique are not entirely clear.Patients undergoing elective PCI from January 2000 to December 2010 were included. The postprocedural and late clinical outcomes of 444 patients who underwent PCI with DS were compared with a propensity-matched population of 444 subjects treated with PD.The two groups were well matched to 27 baseline clinical, procedural, and angiographic characteristics, thus allowing for a more accurate evaluation of the independent value of the stenting technique. Intravascular ultrasound was used in more than 60% of interventions in both groups. PCI performed with PD were longer (DS 45 ± 19.28 vs. PD 56 ± 23.72 minutes, P = 0.001), used more contrast (DS 154 ± 65.88 vs. PD 186 ± 92.84 cc, P = 0.001), and more frequently used balloon postdilation (DS 0% vs. PD 27.3%, P = 0.001). The incidence of periprocedural myocardial infarction (PPMI) was similar between DS- and PD patients (5.3% vs. 5.4%, P = 0.91). Likewise, the 1-year rates of major adverse cardiac events (8.4% vs. 6.3%, P = 0.25), target lesion revascularization (3.9% vs. 2.5%, P = 0.24), and definite stent thrombosis (0.2% vs. 0.9%, P = 0.37) were similar among DS and PD patients, respectively.During elective PCI, DS decreases overall procedure time and resource utilization, but fails to reveal an independent clinical advantage as there is no demonstrable benefit in regard to the incidence of PPMI, restenosis, or overall clinical outcomes up to 1-year of follow-up.

RESUMEN Los estudios ontogénicos permiten conocer cómo se generan las diferencias morfológicas que encontramos en adultos. Éstas resultan de la asociación diferencial entre rasgos morfológicos, lo que puede deberse tanto a factores del desarrollo como funcionales. De acuerdo a la hipótesis funcional, los cambios en las estructuras óseas son consecuencia de la influencia de tejidos blandos, cavidades y órganos (matriz funcional). En este trabajo se analizaron dos estructuras craneofaciales: la bóveda, formada por varios huesos y una matriz funcional homogénea y el maxilar, un hueso único afectado por diversas matrices, para poner a prueba la hipótesis que postula que durante la ontogenia cambian los patrones de covariación. Se relevaron puntos craneofaciales sobre 267 cráneos de adultos y subadultos, se aplicó Análisis de Componentes Principales para establecer la variación en forma a lo largo de la ontogenia y se realizó un análisis de correlación entre las matrices de covarianza de las sucesivas edades para evaluar el cambio en los patrones de integración morfológica. Los resultados indicaron que mientras en la bóveda los patrones de covariación no cambian durante la ontogenia, esto sí ocurre en el maxilar. Los patrones de covariación de estas estructuras se comportarían en relación a la cantidad y características de las matrices asociadas ABSTRACT Ontogenetic studies help to understand how morphological differences found among adults arise. These are the result of differential association among morphological traits, which can be due to developmental as well as functional factors. According to the functional paradigm, change in bone structures is the result of the influence of associated soft tissue, cavities and organs (functional matrix). In this work, two craniofacial structures were analysed: the vault, composed by several bones and a homogeneous functional matrix, and the maxilla, a single bone affected by diverse matrices. The hypothesis that indicates that along ontogeny covariation patterns change was tested. Landmarks were registered on 267 adult and subadult skulls. Principal Components Analysis was applied in order to assess shape variation along ontogeny. To examine ontogenetic change in the morphological integration pattern, a correlation analysis between the successive covariation matrices was carried out. The results indicate that while in the vault there are not ontogenetic differences in covariation patterns, these patterns change in the maxilla. Covariation patterns in these structures would behave according to the number and characteristics of associated matrices. Publicado on-line:15/08/2012

RESUMEN Los cambios craneofaciales resultantes del envejecimiento se atribuyen principalmente a la pérdida dentaria, no habiendo modificaciones en otras estructuras craneanas. El objetivo de este trabajo es analizar dichos cambios en distintos componentes craneofaciales, probándose la hipótesis que indica que, luego de alcanzada la adultez, solo hay cambios morfológicos localizados resultantes de la pérdida dentaria. Se tomaron medidas neurales y faciales en 70 individuos de origen francés con edades entre 22 y 102 años. Se registró el estado de la dentición, clasificándolos en tres grupos, como: ausencia total de dientes (ATD), ausencia parcial de dientes (APD) y dentición completa (DC). Se realizó Análisis de Componentes Principales y ANCOVA a fin de evaluar el cambio morfológico según la edad y el estado dentario. Los resultados indicaron que con la edad hay una disminución de tamaño craneofacial en todas las medidas, aún en estructuras no directamente implicadas en el soporte dentario; sin embargo, los individuos de mayor edad muestran también mayor pérdida dentaria. Ajustada para la edad, la única reducción asociada al estado de la dentición se evidencia en el ancho y la longitud alveolares, el ancho masticatorio y la altura facial. Aunque el patrón de variación podría relacionarse con la pérdida dentaria, no es independiente de otros procesos biológicos. Los individuos que carecen completamente de dientes presentarían cambios acumulativos con la edad, debido a que la menor cantidad de dientes influye en el tipo de nutrición y en consecuencia, en el complejo craneofacial. Por lo tanto, la hipótesis propuesta se rechaza. ABSTRACT Craniofacial modifications, which come about with aging, are usually attributed to tooth loss, and it is accepted that other skull structures remain unchanged. The purpose of the study was to analyze morphological changes in different craniofacial components. The hypothesis to be tested states that once adulthood is reached, craniofacial changes are localised and only associated with tooth loss. Neural and facial measurements were taken on 70 French individuals aged between 22 and 102 years. Dental state was assessed and individuals were divided into three categories: total absence of tooth (ATD), partial absence of tooth (APD) and complete dentition (DC). Principal Components Analyses and ANCOVA were carried out to evaluate morphological change related to age and dental state. The results indicated that there was a decrease of craniofacial size in all the measurements including those that described structures that were unrelated to dental support although older individuals showed also a remarkable tooth loss. When age was adjusted, the only reductions associated with dental state were found in alveolar width and length, masticatory width and facial height. Although this pattern of variation could be related to tooth loss, it may depend on several biological changes with aging. Tooth loss and aging are two linked biologica processes since individuals that lack tooth completely may present accumulative changes with age because the reduced number of tooth influences on the kind of nutrition and, thus, on the craniofacial complex. Therefore, the stated hypothesis was rejected

End-stage renal disease (ESRD) is known to correlate with poor outcome in patients undergoing percutaneous coronary intervention (PCI). This study examines the impact of diabetes mellitus (DM) on the long-term outcome of patients with ESRD on chronic hemodialysis.A cohort of patients with ESRD on chronic hemodialysis, who underwent PCI with drug-eluting stents, was followed for 1 year. The clinical outcome in this population was compared retrospectively based on the presence of DM. Major adverse cardiac events (MACE) as the composite of all-cause death, Q-wave myocardial infarction and target lesion revascularization (TLR), as well as TLR as an individual outcome, were the main end points of the study.In the study cohort (n = 198), 48.5% had DM. Diabetic patients were more commonly female. The lesion characteristics were similar between groups except for more frequent saphenous vein graft intervention in nondiabetics. At 1-year follow-up there was no difference in the rate of MACE between diabetic and nondiabetic patients (40.4% vs. 39.3%, respectively, p = 0.89), driven primarily by a very high mortality rate (1-year overall mortality of 33.5%). After adjustment for the relevant clinical co-variables, DM was not associated with the composite end point. However, diabetic patients had a significantly higher incidence of 1-year TLR compared to nondiabetics (13.8% vs. 3.6%, respectively, p = 0.04).The prognosis of patients with ESRD after PCI is dismal with a very high overall mortality rate regardless of the presence of DM. Patients with ESRD appear to be at higher risk for the need of revascularization.

This study was undertaken to evaluate the safety of bivalirudin (BIV) use during percutaneous coronary intervention (PCI), following thrombolytic therapy in patients with ST-segment elevation myocardial infarction (STEMI).BIV has emerged as a safer anticoagulant than unfractionated heparin (UFH) during primary PCI; however, its use in patients who receive thrombolytic therapy has not been established.A consecutive series of 104 patients who presented with STEMI treated with full-dose thrombolytics and who subsequently received PCI within 6 hr was identified and analyzed. BIV use was compared with UFH for in-hospital bleeding and ischemic events. The primary end points were the rate of major bleeding and the rate of net adverse clinical events as defined in the Harmonizing Outcomes with Revascularization and Stents in Acute Myocardial Infarction trial. The study cohort consisted of 104 patients, of whom 47 (45%) received BIV and 57 (55%) received UFH.Patients on BIV were more frequently preloaded with clopidogrel, while intraprocedural glycoprotein IIb/IIIa inhibitors were used only in UFH patients. In-hospital death, ischemic events, and thrombolysis in myocardial infarction major bleeding occurred more frequently in patients treated with UFH. The net adverse clinical events rate was lower in the intraprocedural BIV group (3 [6.4%] vs. 12 [21.1%] UFH, P = 0.034).The use of BIV in patients presenting with STEMI who were pretreated with thrombolytic therapy and who subsequently underwent PCI is safe and is associated with less ischemic and bleeding events when compared with UFH, and should be considered as the first line anticoagulant for these patients during PCI.

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RESUMEN: Según el modelo clásico de poblamiento americano, los amerindios poseen un ancestro básico de tipo mongoloide, con diferenciaciones secundarias originadas por procesos microevolutivos locales. Toda comparación basada en distancias o en componentes funcionales, debería sostener entonces, la hipótesis: "las distribuciones amerindias se aproximan en mayor grado a las de las poblaciones asiáticas y en menor grado a las de las poblaciones europeas". Por componer los araucanos una población típicamente amerindia, debe esperarse que presenten mayor similitud morfológica con grupos asiáticos mongolizados y secundariamente, afinidades con grupos de extracción no mongoloide, dadas estas últimas por procesos evolutivos de adaptación convergente o mestizaje. El objeto del presente trabajo es corroborar el rechazo de dicha hipótesis (Pucciarelli et al.,1999), a través de un conjunto de nuevas comparaciones. Se procedió a medir 17 cráneos araucanos masculinos mediante 46 variables de las propuestas por Howells (1973) y compararlos con muestras de europeos (norse, zalavar, berg), asiáticos (chinos, japoneses, ainu, buriat, coreanos), filipinos y esquimales, cuyos datos fueron extraídos de los archivos proporcionados por Howells (1996). La estadística realizada consistió en análisis canónico, análisis discriminante, y "clusters" jerárquicos, mediante el programa Systat 7.0. Se halló que: (a)la elipse de distribución de los araucanos fue casi equidistante respecto de norse y sudjaponeses, siendo la distancia entre éstos menor que la de cada uno de ellos respecto de araucanos; (b)en el primer "cluster" con europeos, filipinos, sudjaponeses y ainu, los araucanos se separaron en un "subcluster" aislado y a la mayor distancia, le siguieron los ainu en un segundo "subcluster", mientras que los filipinos ocuparon un tercero, junto con europeos y japoneses; (c)en el segundo "cluster", los araucanos se agruparon en forma intermedia entre chinos, japoneses y coreanos por un lado y europeos orientales y occidentales por el otro, mientras que el grupo buriat se separó a la mayor distancia, agrupándose en otro "subcluster". Con estos resultados se confirma la existencia de una mayor proximidad de araucanos con europeos que la esperada por el modelo clásico de migración transberingea; que la proximidad de los araucanos respecto de europeos no obedece a un modelo de mestizaje asiático-europeo como el producido con los filipinos y que la distancia entre araucanos y japoneses detectada no es exagerada, por cuanto si se hubiera comparado contra un grupo siberiano como los buriats, la separación asiático-araucana hubiera sido todavía mayor. La mongolización asiática del cuaternario seguida de una miscegenación holocénico temprana con poblaciones del substrato paleoindio americano, junto con procesos adaptativos al nuevo ambiente de caza-recolección, es la dinámica que mejor explica la formación de la estructura craneofacial araucana actual. Se adopta por consecuencia la acción conjunta de los procesos descriptos por las hipótesis de mongolización-adaptación y mongolización-miscegenación (Pucciarelli et al.,1999) para explicar la particular morfología craneofacial hallada en los araucanos de La Pampa. Rev. Arg. Antrop. Biol. 2(1): 187-200, 1999. ABSTRACT: According to the classical American peopling model, the Amerindians -which include most of the extinct and extant American Indian populations- came to America from the North of Asia, passing through the Bering Strait and the Aleutian Islands. The Amerindians have, then, a basic Asian Mongoloid configuration with secondary differentiations caused by local microevolutionary processes. All comparisons based in distances and/or functional components should support the following hypothesis: "the Amerindian distributions should approach in a higher degree those of the Asian populations and in a lesser degree those of the European ones". Since the Araucanians are a typically Amerindian population, a greater morphologic similitude with Mongoloid Asian populations and secondary affinities with non-Mongoloid groups, caused by evolutionary processes of adaptation or miscegenation, are then expected. The object of the present study is to corroborate the rejection of the mentioned hypothesis (Pucciarelli et al., 1999). Seventeen male Araucanian skulls were measured according to 46 variables proposed by Howells (1973). They were compared with samples of Europeans (Norse, Zalavar, Berg), Asians (Chinese, Japanese, Korean, Ainu, Buriat), Philippines, and Eskimos. Data were drawn from Internet files (Howells,1996). The statistics employed consisted in canonical and discriminant analyses, and a hierarchical clustering. The Systat 7.0 package was employed. The results were the following: (a) the distribution ellipses of the Araucanians were almost equidistant with respect to both the Japanese and the Norse, the distance between the last two groups being lower than the distance of each of them with respect to the Araucanians; (b) in the first cluster, in which the Araucanians were compared with Nordics, Philippines, South Japanese, and Ainu, the first were separated in a single sub-cluster, while the Ainu were at the greatest distance in a second sub-cluster. The Philippines, Japanese and Nordics outlined a third sub-cluster, in which the first group was placed between the last two; (c) in the second cluster, the Araucanians were compared with Chinese, Japanese, Europeans, Buriats and Eskimos. While the last two groups remained separated from each other and from the remainders, the Araucanians joined the Chinese, Japanese, and Europeans. These results showed that the Araucanians are almost equidistant to the Chinese-Japanese and the Europeans, and that the Chinese behaved like the Japanese, the latter being, consequently, not a very specialized people in the Asian world. It was concluded that the Araucanians are more closely related to European than to Asian populations, that this proximity did not obey to a recent Asian-European mixing process, and that the Japanese are not a specialized branch of Mongoloids. The Asian Mongolism process of the Quaternary, the miscegenation of migrants through the Bering Strait with ancient American Paleoindians, and the microevolutionary processes to adapt migrants to hunter-gathering acted on the formation of the Amerindians. Consequently, the hypotheses of mongolization-adaptation and mongolization-miscegenation (Pucciarelli et al., 1999) can explain the formation of the modern Araucanians. Rev. Arg. Antrop. Biol. 2(1): 187-200, 1999.

RESUMEN: Se acepta que el denominado substrato amerindio -que incluye a la mayoría de las poblaciones americanas actuales e históricas- incursionó en dirección norte-sur, desde el noreste asiático, pasando por el estrecho de Bering y el rosario de las Aleutianas. Según este modelo, las poblaciones amerindias poseen un ancestro básico de tipo mongoloide, con diferenciaciones secundarias originadas por procesos microevolutivos locales. Toda comparación basada en distancias o en componentes funcionales, debería entonces sostener la hipótesis: "las distribuciones amerindias se deben aproximar en mayor grado a las de las poblaciones asiáticas y en menor grado a las de las poblaciones europeas". Por componer los araucanos una distribución tipicamente amerindia, debe esperarse entonces que presenten mayor similitud morfológica con grupos asiáticos mongolizados y secundariamente, afinidades con grupos de extracción no mongoloide, dadas estas últimas por procesos evolutivos de adaptación o mestizaje. El objeto del presente trabajo es determinar si a nivel craneofacial se cumple el modelo propuesto a través de la metodología craneofuncional. Se procedió a medir los componentes funcionales anteroneural, mesoneural, posteroneural, ótico, óptico, respiratorio, masticatorio y alveolar en 48 cráneos provenientes de muestras japonesa, francesa y araucana. Se observó que: (a)las elipses de distribución producidas por el análisis canónico ubicaron a los araucanos en una posición casi equidistante entre japoneses y europeos; (b)los componentes funcionales discriminados por el análisis univariado fueron tres para la comparación europeo-japonesa (óptico, masticatorio y alveolar), los mismos tres para la comparación araucano-japonesa (pero con sentido inverso) y sólo el efecto tamaño del componente facial para la comparación araucano-europea. Con estos resultados se rechaza la hipótesis planteada y se sugiere que, además de los factores microevolutivos que condujeron a una adaptación por caza-recolección, los araucanos sufrieron primariamente el proceso de mongolización asiática acaecido durante el último estadial del pleistoceno y secundariamente una activa miscegenación con poblaciones del denominado substrato paleoindio, de carácter asiático no-mongoloide y del cual los restos de Warm Mineral Springs, Spirit Cave, Kennewick, Lagoa Santa, Tequendama y Palli Aike serían entre otros, sus representantes más conspicuos. Rev. Arg. Antrop. Biol. 2(1): 163-186, 1999. ABSTRACT: It is known that the Amerindians -which include most of the extinct and extant American Indian populations- came to America from the Northeast of Asia, passing through the Bering Strait and the Aleutian Islands. According to this model, the Amerindian populations have a basic Asian Mongoloid configuration, which was secondarily modified by local microevolutionary processes. All comparisons based in distances and/or functional components should then support the hypothesis that "the Amerindian distributions should approach in a higher degree those of the Asian populations and in a lesser degree those of the European ones". Since the Araucanians constitute a typically Amerindian population, a greater morphologic similitude with Mongoloid Asian populations and secondary affinities with non-Mongoloid groups, caused by evolutionary processes of adaptation or miscegenation, are then expected. The object of the present study is to test the validity of this model at craniofacial level. The functional anterior neural, mid neural, posterior neural, otic, optic, respiratory, masticatory, and alveolar components were measured in 48 crania belonging to well-identified European, Japanese and Araucanian collections. It was observed that: (a) the distribution ellipses given by the canonical analysis were concordant in placing the Araucanians almost equidistantly between the Japanese and the Europeans; (b) the functional components discriminated in shape by the univariate analysis were the optic, masticatory and alveolar ones for both the European-Japanese comparison and -although with inverse meaning- the Japanese-Aracanian one. Whereas, only changes in facial size characterized the European-Araucanian comparison. These results allowed us to reject the stated hypothesis. It is suggested that, besides the Holocene adaptation to hunter-gathering, the Araucanians underwent -after the Pleistocene Mongolization process- an active miscegenation with non-Mongolized Asian Paleoindian populations, the skeletons of Warm Mineral Springs, Spirit Cave, Kennewick, Lagoa Santa, Tequendama and Palli Aike being their most conspicuous examples. Rev. Arg. Antrop. Biol. 2(1): 163-186, 1999.

The evolution of microstructure and electrical properties of silver-based thick-film metallizations of silicon solar cells prepared by infrared firing processes has been investigated. The performance of the cells are shown to be dependent on several dynamical and diffusive phenomena. In particular, the sintering of silver grains, silver diffusion into the glass, and the flow of glass at the metal/silicon interface strongly affect important characteristics of the cells such as sheet and contact resistivities and the adhesion of fingers and bus bars. The existance of an optimum value of the peak firing temperature is observed and explained in terms of competitive phenomena occurring at the metal/silicon interface. Moreover it is shown that IR firing treatments require a careful consideration of the sequence of printing and firing steps. The features of heat treatments performed in conveyor belt furnances using Joule and infrared sources are compared.

The results of a study on the structural and electrical properties of aluminium-based thick film metallization for the back contact of n + /p silicon solar cells are reported. The study takes advantage of observations with a scanning electron microscope and analyses with an electron microprobe and Auger electron spectroscopy. The phases of AlSi formation and densification are described as well as the AlSi interactions. Some insights into the proper choice of aluminium-based inks are discussed and it is shown how the ink firing conditions are correlated with the efficiency of the solar cells.