An 11,000-year record of depositional environmental change based upon particulate organic matter and stable isotopes (C and N) in a lake sediment in southeastern Brazil

The aim of this paper is to reconstruct an 11,000-year history of depositional environmental change in southeastern Brazil, based upon the integration of particulate organic matter and stable isotope (C and N) data from a 136-cm sediment core from Lake Canto Grande. These proxies are used to explore the evolution of terrestrial and marine influence on the lake. Isotopic (δ13C: -7.8‰ to -31.9‰; δ15N: -0.07‰ to 4.9‰) and elemental (total organic carbon - TOC: 0.58% to 37.19%; total nitrogen - TN: 0.08% to 1.73%; C/N: 0.3 to 54.7) values recorded in Lake Canto Grande suggest that the sedimentary organic matter was derived from mostly C3 land plants and freshwater phytoplankton. Particulate organic matter and cluster analyses distinguished four associations characterized by the predominance of amorphous organic matter, followed by phytoclasts and palynomorphs. These results indicate two different phases of lake evolution. The first phase (136 - 65 cm; ~10,943 cal yr. B.P. to ~8,529 cal yr. B.P.) is recorded by sand layers interbedded with mud, which contain amorphous organic matter (AOM, 45-59%) and phytoclasts (opaques - OP: 6-18%; non-opaques – NOP: 17-23%) which indicate a floodplain area. The second phase (65 – 0 cm; ~8,529 cal yr. B.P. to ~662 cal yr. B.P.) comprises mud, AOM (68-86%) and palynomorphs (PAL, 8-16%) related to lake establishment comparable to modern conditions. Thus, characterizing particulate organic matter, in combination with stable isotopes, proved to be invaluable proxies for lacustrine paleoenvironmental change through the Holocene

Out of Amazonia: late-Holocene climate change and the Tupi–Guarani trans-continental expansion

The late Holocene expansion of the Tupi-Guarani languages from southern Amazonia to SE South America constitutes one of the largest expansions of any linguistic family in the world, spanning ~ 4000 km between latitudes 0°S and 35°S at about 2500 yr B.P. However, the underlying reasons for this expansion are a matter of debate. Here, we compare continental-scale palaeoecological, palaeoclimate, and archaeological datasets, to examine the role of climate change in facilitating the expansion of this forestfarming culture. Because this expansion lies within the path of the South American Low-Level Jet, the key mechanism for moisture transport across lowland South America, we were able to explore the relationship between climate change, forest expansion, and the Tupi-Guarani. Our data synthesis shows broad synchrony between late Holocene increasing precipitation and southerly expansion of both tropical forest and Guarani archaeological sites – the southernmost branch of the Tupi-Guarani. We conclude that climate change likely facilitated the agricultural expansion of the Guarani forest-farming culture by increasing the area of forested landscape that they could exploit, showing a prime example of ecological opportunism

Cold and humid Atlantic forest during the late glacial, northern Espírito Santo state, southeastern Brazil

The Atlantic Rainforest, covering the area from the northern Espirito Santo to Southern Bahia states, has been considered as a stable forest during Pleistocene Glacial times. Despite the modelling and phylogenetic studies, this hypothesis has never been tested with empirical paleo-data and vegetation reconstruction. By using palynology, radiocarbon dating, carbon and nitrogen elemental and isotope of organic matter, we reconstructed the vegetation dynamics and inferred climatic changes since Late Pleistocene in the centre of this global biodiversity hotspot. Our results show that the forest biome was resilient to Last Glacial Maximum - LGM conditions, but floristics has changed when compared to nowadays. Since late glacial, the dense forest changed from cold to warm specimens. Major vegetation changes also occurred during early and mid-Holocene less humid conditions, with an opening of the forest, suggesting that future drought may have negative impacts and highlighting the importance of forest conservation to keep the Atlantic Rainforest biodiversity

NÄYTTÖÖN PERUSTUVA HOITOTYÖ EKG-REKISTERÖINNISSÄ

TIIVISTELMÄ Opinnäytetyössämme käsittelemme laadukkaan elektrokardiografian rekisteröintiä. Tutkimuksen tarkoituksena oli kuvailla hoitajien toimintaa EKG-rekisteröintitilanteissa terveyskeskuksen päivystyksessä, yhteispäivystyksessä sekä sairaalan laboratoriossa. Opinnäytetyömme tavoitteena oli selvittää, miten hoitajat toteuttavat EKGrekisteröinnin eri osa-alueet. Tavoitteena oli selvittää myös, miten hoitajat arvioivat EKG-tulosteen laatua. Tutkimuksen toteutimme havainnoimalla eri työyksiköissä EKGrekisteröintiä. Havainnoinnissa käytimme strukturoitua havainnointilomaketta sekä kenttäpäiväkirjaa. Havainnointiin osallistui yhteensä 6 henkilöä, jotka olivat sekä sairaanhoitajia, että laboratoriohoitajia sekä yksi lähihoitajaopiskelija. Tutkimustuloksista kävi ilmi, että koulutuspohjalla on merkitystä siihen, miten rekisteröijä rekisteröi EKG:n. Laboratoriohoitajilla oli enemmän tietoa EKGrekisteröinnistä kuin sairaanhoitajilla. Lähihoitajaopiskelijan EKG-rekisteröintitaito oli samankaltainen kuin sairaanhoitajien. Rekisteröijät tietävät EKG-rekisteröinnin pääpiirteet ja niiden toteuttamisen. Rekisteröijien toiminta käytännössä osoittaa kuitenkin, että perehdytystä tai lisäkoulutusta olisi hyvä olla saatavilla. Tutkimustuloksista nousee esille sekä heikkouksia että vahvuuksia osaamisessa ja erilaisten asioiden huomioonottamisessa sekä tekemisessä. Taitoa rekisteröijillä on selvästi, mutta tutkittavan henkilön tilan kriittisyys tai rekisteröijän epätietoisuus EKGrekisteröintiin kuuluvista asioista vähentää EKG-tulosteen laadukkuutta.ABSTRACT In our thesis we deal with high-quality electrocardiogram registration in a real nursing situations. The purpose of this study is to describe how the nurses behave in ECG monitoring situations at the health centre emergency department, the hospital emergency department and in the laboratory. Our study objective was to determine how nurses carry out the different parts of the ECG registration. The aim was also to explore how nurses assess the quality of the ECG printout. We carried out the study by observing the ECG registration in different work units. We carried out the observation by using a structured observation form and the a field diary. The observation was attended by six people who were registered nurses, laboratory technicians and one student of practical nursing. The research results showed that education background matters when the registrant registered the ECG. The laboratory techinicians had more knowledge about the ECG than the registered nurses. The student of practical nursing had the similar skills of ECG registration as the registered nurses. The registrants can use the ECG equipment and they know the main points of ECG registration. It would be good to have induction training or additional training available. The results of the study show that the registrants have strenghts and weaknesses in their skills of ECG registration and how they take into account various things and how they work. The registrants have a clear knowledge of registration in practice but the ECG printout quality may suffer when the patient's condition is acute or when the registrant is unaware of the matters concerning ECG registration

Palaeovegetation and palaeoclimate dynamics during the last 7000 years in the Atlantic forest of Southeastern Brazil based on palynology of a waterlogged sandy soil

Mineral soils are usually considered inappropriate for pollen analysis because of the poor quality of pollen and spore preservation and the disturbed stratigraphy. However, here we present a 57 cm core, collected from a waterlogged sandy soil in the lowland Atlantic Forest of SE Brazil, which shows good stratigraphy and good preservation of pollen and spores since ~7000 cal. BP, both in organic and in mineral horizons. By the other hand, the decomposition of the organic matter and its translocation along the soil profile led to changes of C and N results (TOC, TN, C/N, δ13C and δ15N). Mid-Holocene palaeoclimate inferences from this study are in accordance with climate fluctuations presented in previous studies for Central, Southeastern and Southern Brazil, when a change to more humid climate occurred at ~7000 cal BP. The process responsible for the presence of biological proxies along this sandy soil profile involves the continuous deposition of these proxies together with litter and sand, and the subsequent decomposition of the litter. Ultimately, this process led to the vertical accretion of the sand with the more resistant organic structures preserved in stratigraphic sequence. The preservation of pollen and spores along the profile is probably caused by low pH and redoximorphic conditions due to water saturation. This study suggests the potential for retrieving useful palaeoecological information from mineral and organic horizons of tropical waterlogged sandy soils, which is especially useful for those regions where traditional pollen archives (lakes and peat bogs) are absent