Susceptibility, d13C and Iron of Site 171-1051

Current models of the global carbon cycle lack natural mechanisms to explain known large, transient shifts in past records of the stable carbon-isotope ratio (delta13C) of carbon reservoirs. The injection into the atmosphere of ~1,200-2,000 gigatons of carbon, as methane from the decomposition of sedimentary methane hydrates, has been proposed to explain a delta13C anomaly associated with high-latitude warming and changes in marine and terrestrial biota near the Palaeocene-Eocene boundary, about 55 million years ago. These events may thus be considered as a natural 'experiment' on the effects of transient greenhouse warming. Here we use physical, chemical and spectral analyses of a sediment core from the western North Atlantic Ocean to show that two-thirds of the carbon-isotope anomaly occurred within no more than a few thousand years, indicating that carbon was catastrophically released into the ocean and atmosphere. Both the delta13C anomaly and biotic changes began between 54.93 and 54.98 million years ago, and are synchronous in oceans and on land. The longevity of the delta13C anomaly suggests that the residence time of carbon in the Palaeocene global carbon cycle was ~120 thousand years, which is similar to the modelled response after a massive input of methane. Our results suggest that large natural perturbations to the global carbon cycle have occurred in the past-probably by abrupt failure of sedimentary carbon reservoirs-at rates that are similar to those induced today by human activity.

Clay mineralogy of South Atlantic surface sediments

Surface samples, mostly from abyssal sediments of the South Atlantic, from parts of the equatorial Atlantic, and of the Antarctic Ocean, were investigated for clay content and clay mineral composition. Maps of relative clay mineral content were compiled, which improve previous maps by showing more details, especially at high latitudes. Large-scale relations regarding the origin and transport paths of detrital clay are revealed. High smectite concentrations are observed in abyssal regions, primarily derived from southernmost South America and from minor sources in Southwest Africa. Near submarine volcanoes of the Antarctic Ocean (South Sandwich, Bouvet Island) smectite contents exhibit distinct maxima, which is ascribed to the weathering of altered basalts and volcanic glasses. The illite distribution can be subdivided into five major zones including two maxima revealing both South African and Antarctic sources. A particularly high amount of Mg- and Fe-rich illites are observed close to East Antarctica. They are derived from biotite-bearing crystalline rocks and transported to the west by the East Antarctic Coastal Current. Chiorite and well-crystallized dioctaedral illite are typical minerals enriched within the Subantarctic and Polarfrontal-Zone but of minor importance off East Antarctica. Kaolinite dominates the clay mineral assemblage at low latitudes, where the continental source rocks (West Africa, Brazil) are mainly affected by intensive chemical weathering. Surprisingly, a slight increase of kaolinite is observed in the Enderby Basin and near the Filchner-Ronne Ice shelf. The investigated area can be subdivided into ten, large-scale clay facies zones with characteristic possible source regions and transport paths. Clay mineral assemblages of the largest part of the South Atlantic, especially of the western basins are dominated by chlorite and illite derived from the Antarctic Peninsula and southernmost South America and supported by advection within the Circumantarctic Deep Water flow. In contrast, the East Antarctic provinces are relatively small. Assemblages of the eastern basins north of 30°S are strongly influenced by African sources, controlled by weathering regimes on land and by a complex interaction of wind, river and deep ocean transport. The strong gradient in clay mineral composition at the Brazilian slope indicate a relatively low contribution of tropically derived assemblages to the western basins.

(Table 1) Composition of interstitial waters from ODP Leg 125 sites

Pore waters were collected from nine sites during Leg 125 of the Ocean Drilling Program (ODP). The first four sites (778-781) were drilled in the Mariana forearc on and near Conical Seamount, an active serpentine "mud volcano" located about 80 km behind the trench axis and 120 km in front of the active island arc. The last five sites (782-786) were drilled in the Izu-Bonin forearc between the trench and the outer arc high. Pore waters from the five sites from both areas that penetrated serpentine silts (Sites 778,779,780,783, and 784) are discussed in detail by Mottl (this volume). Here we report analyses of the pore waters from all nine sites for Li, Rb, Sr, Ba, Mn, B, and the sulfur isotopic ratio of dissolved sulfate. Sampling methods and results of analyses for major and minor species determined aboard ship were presented by Fryer, Pearce, Stokking, et al. (1990, doi:10.2973/odp.proc.ir.125.1990).

The Relationship Between Cadwaladerite Al(OH)2Cl∙4H2O and Lesukite Al2(OH)5Cl∙2H2O as Investigated by SEM, PXRD, FTIR and Raman Spectroscopy

Cadwaladerite (Al(OH)2Cl∙4H2O) collected from Cerro Pintados, Chile described by Gordon in 1941 is designated as “doubtful” by the IMA. Material collected from the same locality in 2015 resembling the description of cadwaladerite gave a powder XRD pattern similar to lesukite (Al2(OH)5Cl∙2H2O). However, Gordon provided no X-ray data for his material from Cerro Pintados. In order to determine whether cadwaladerite and lesukite are the same mineral species, measurements were made on a suite of samples from various localities. A portion of the material collected by Gordon in 1941 was also obtained from the Mineralogical Museum of Harvard University. Type material of lesukite from a fumarolic environment at the Tolbachik Fissure in Kamchatka, Russia was obtained as well as lesukite from the Maria Mine, Chile (Arica Province) and a previously undescribed locality for lesukite (Barranaca del Sulfato, Mejillones Peninsula, Antofagasta Province). All samples are yellow to yellow-orange in colour and all exhibit small cubic crystals (up to 50µm), even Gordon’s cadwaladerite which was thought to be amorphous. The Chilean samples are all associated with halite and sometimes with anhydrite. These five samples were studied by SEM, FTIR, powder XRD, and Raman spectroscopy. A ratio of Al:Cl less than or equal to 1.3:1 was observed for all the samples, including measurements made on lesukite from the Russian locality Vergasova et al. studied in 1997, and determined to have a 2:1 ratio. SEM-EDS analyses also show all samples to have minor iron substitution, as well as copper substitution in two samples. FTIR spectra are very similar for all samples. Raman spectroscopy done on both samples collected in Cerro Pintados and the Russian lesukite gave similar spectra. Powder XRD analyses on all samples showed spectra identified to be lesukite, including Gordon’s cadwaladerite. Crystal cell parameters calculated from powder XRD ranged from 19.778Å to 19.878Å. Results using modern instrumental techniques confirm Gordon’s cadwaladerite, collected in 1939 and described in 1941, and lesukite are the same mineral species.

Examination of body image among Canadian adolescents: Relations with physical activity and screen time

Background: Adolescence is a period of life associated with self-perceptions of negative body image. Physical activity levels are low and screen time levels are also high during this stage. These perceptions and behaviours are associated with poor health outcomes, making research on their determinants important. With adolescent populations, certain groups may be at higher risk of body dissatisfaction than others, and body dissatisfaction may influence individual physical activity and screen time levels. Objectives: The objectives of this thesis were to: 1) describe body image among young Canadians, examining possible health inequalities 2) estimate the strength and significance of associations between body satisfaction, physical activity and screen time, and 3) examine the potential etiological role of biological sex. Methods: Objective 1: The 2013/2014 Health Behaviour in School-aged Children study was employed. Sex-stratified Rao-Scott chi-square analyses were conducted to examine associations between socio-demographic factors and body satisfaction. Objective 2: The 2005/2006 and 2013/2014 cross-sectional and 2006 longitudinal HBSC data sets were used. Sex-stratified modified Poisson regressions were conducted and risk estimates and associated confidence intervals obtained. Results: Objective 1: Among males, being older, of East and Southeast Asian ethnicity, and reporting low SES all were associated with body dissatisfaction. Among females, being older, of Arab and West Asian or African ethnicity, being born in Canada, and reporting low SES were all associated with being body dissatisfied. Objective 2: Cross-sectionally, males who reported ‘too fat’ body dissatisfaction were more likely to be physically inactive. Adolescents of both sexes who reported ‘too fat’ body dissatisfaction were more likely to engage in high levels of screen time. Data from the longitudinal component supported the idea that male ‘too fat’ body dissatisfaction temporally leads to physical inactivity, but showed an inverse relationship between body dissatisfaction and screen time. Conclusions: Objective 1: Future prevention efforts in Canada should target subgroups to effectively help those at greatest risk of body dissatisfaction, and ameliorate potential inequalities at the population level. Objective 2: The presence of these relationships may inform future interventions as part of a multi-factorial etiology, in order to increase physical activity and decrease screen time among youth.

Changes in the Ecology and Abundance of Smallmouth Bass in Lake Ontario: 1958-2014

Understanding the reasons for long-term population change in a species requires an evaluation of ecological variables that may account for the observed dynamics. In this study, long-term changes in indices of Smallmouth Bass condition and population levels were examined for eastern Lake Ontario and the Bay of Quinte. Smallmouth Bass are an extremely important recreational fish species native to Lake Ontario. They have experienced numerous changes in their environment through direct human impacts, climate change, predation, and habitat sharing with non-native species. Smallmouth Bass have experienced an increase in body length and weight likely due to a diet shift from crayfish to predominantly Round Gobies which has allowed them to increase their growth rate. According to existing assessment data however, this increase in body size has not been associated with an increase in abundance. Long-term data from gill net sampling shows that Smallmouth Bass populations have been declining since the late 1980s with no indication of recovery. This could be due to a variety of factors, but it is most likely due to a change in the selectivity of gill nets because of the change in body size as well as a habitat shift away from gill net sampling sites. Adjusting for gill net selectivity has revealed that sub-adult bass abundance is currently greater than it was historically, and that very large bass are likely not being retained within the gill nets that are currently used. The use of a long-term data set in this study has led to a much better understanding of Smallmouth Bass abundance and ecology.

Propuesta sostenible para mitigar los efectos climáticos adversos en una ciudad costera de Argentina

Los indicadores de sostenibilidad climática constituyen herramientas fundamentales para complementar las políticas de ordenamiento del territorio urbano y pueden beneficiar la calidad de vida sus habitantes. En el presente trabajo se diseñó un indicador climático urbano para la ciudad de Bahía Blanca considerando variables meteorológicas y análisis de la percepción social. El mismo permitió delimitar la ciudad en cuatro regiones bien diferenciadas entre sí. A partir de entonces, se realizó una propuesta sostenible para mitigar los efectos adversos del clima a partir de la aplicación del método DPSIR. Las mismas estuvieron destinadas a mejorar las condiciones de vida de la población. Los resultados permitieron considerar que una pronta implementación de la misma junto con una activa participación de los actores sociales y los tomadores de decisiones es necesaria para mejorar las condiciones actuales en la que se encuentra la ciudad. Con las medidas propuestas, la población local sabrá cómo actuar ante la ocurrencia de distintos eventos extremos, eventos de desconfort climático, etc. Al ser un método sencillo, la metodología aplicada en este estudio puede replicarse en otras ciudades del mundo con el objetivo de mejorar la calidad de vida de los habitantes.

Training proposal in the degree of Master of Early Childhood Education for working the method of historical research in the classroom

Future teachers must be competent in creating educational settings, which provide tools to their students future they can develop a conscious mind, able to interpret their experiences, to make decisions and imagine innovative solutions to help you participate autonomously and responsible in society. This requires an educational system that allows them to integrate the subjective into a broader spatial and temporal context. La patrimonializatión of “Cultural artefacts” and oral history, the basis of which, are found in the active mind and links both the personal and the group experience, don’t only serve as a catalyst to achieving this goal, but rather, they facilitate the implementation of established practice in infant education. To gain this experience we offer the opportunity for students of their degree in Infant Education in the Public University of Navarre, training within the framework of social didactics, allowing students to learn about established practice from iconic, materials and oral sources in the Archive of Intangible Cultural Heritage of Navarra. The vidences points to their effectiveness and presented in a work in progress.

Diversifying From Within: Community Policing and the Governance of Security in Northern Ireland

The subtle and complex nature of Northern Ireland's transitional landscape presents acute difficulties for the community policing concept. As the core to the police reforms in the country, its implementation has faltered in the face of institutional inertia within the Police Service of Northern Ireland (PSNI). This has been further exacerbated by a failure of the police to adequately increase the co-production of security through improved engagement and utilization of Northern Ireland's diverse community infrastructures. This paper will assess the delivery of community policing by the PSNI, while exploring their engagement with Northern Ireland's grass-roots community organizations, and specifically those involved with the governance of security at the local level. Thus, through a framework of adaptation, engagement and delivery of community policing by the PSNI within the unique context of Northern Ireland's security ‘otherness’, the paper will explore the key issues to police–community interaction associated with the broader vision of the Independent Commission on Policing (ICP) on community policing.

Effects of simvastatin in abdominal sepsis in rats

Statins are widely recognized as hypolipemic drugs, but some studies have observed anti-inflammatory and immunomodulatory effects, known as pleiotropic. The aims of this work was to study possible anti-inflammatory effects of simvastatin in abdominal sepsis. Serum pro-inflammatory cytokines and leukocytes count were determined in an experimental model of abdominal sepsis, using cecal ligation and puncture (CLP) in rats. Methods: Twenty eigth Wistar rats weighing 285±12g were randomly divided in: CLP/Sinvastatin rats (n=7), treated with 10 mg/Kg of oral simvastatin 18 and 2 hs berofe CLP; CLP/Saline group rats (n=7), treated with oral saline; group Sham/Simvastatin (n=7), treated with simvastatin, and group Sham/Saline (n=7), treated with saline. Serum TNF-α, IL-1β and IL-6 by ELISA and total leukocytes, neutrophils, lymphocytes, and eosinophils were determined 24 hs after CLP. ANOVA and Tukey test were used considering significant p<0.05. Results: It was demonstrated that serum TNF-α, IL-1β and IL-6 were respectively 364,8±42pg/mL; 46,3±18pg/mL and 28,4±13pg/mL in CLP/Sinvastatin rats, significantly lower (p<0.05) than in group CLP/Saline (778,5±86pg/ml; 176,9±46pg/ ml; 133,6±21 pg/ml, respectively). The same results were observed in total leukocytes and neutrophils counts. Conclusion: These results clearly demonstrate that simvastatin is an effective agent that reduces cytokines levels and leukocyte count in sepsis, independently of its well-known lipid-lowering effects. Thus, HMG-CoA reductase inhibitors like simvastatin have important anti-inflammatory effects in abdominal sepsis in rats

The Influence of Estrogens on the Biological and Therapeutic Actions of Growth Hormone in the Liver

[EN]GH is main regulator of body growth and composition, somatic development, intermediate metabolism and gender-dependent dimorphism in mammals. The liver is a direct target of estrogens because it expresses estrogen receptors which are connected with development, lipid metabolism and insulin sensitivity, hepatic carcinogenesis, protection from drug-induced toxicity and fertility. In addition, estrogens can modulate GH actions in liver by acting centrally, regulating pituitary GH secretion, and, peripherally, by modulating GHR-JAK2-STAT5 signalling pathway