906 resultados para The western Pacific


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The multi-scale synoptic circulation system in the southeastern Brazil (SEBRA) region is presented using a feature-oriented approach. Prevalent synoptic circulation structures, or ""features,"" are identified from previous observational studies. These features include the southward-flowing Brazil Current (BC), the eddies off Cabo Sao Tome (CST - 22 degrees S) and off Cabo Frio (CF - 23 degrees S), and the upwelling region off CF and CST. Their synoptic water-mass (T-S) structures are characterized and parameterized to develop temperature-salinity (T-S) feature models. Following [Gangopadhyay, A., Robinson, A.R., Haley, PJ., Leslie, W.J., Lozano, C.j., Bisagni, J., Yu, Z., 2003. Feature-oriented regional modeling and simulation (forms) in the gulf of maine and georges bank. Cont. Shelf Res. 23 (3-4), 317-353] methodology, a synoptic initialization scheme for feature-oriented regional modeling and simulation (FORMS) of the circulation in this region is then developed. First, the temperature and salinity feature-model profiles are placed on a regional circulation template and objectively analyzed with available background climatology in the deep region. These initialization fields are then used for dynamical simulations via the Princeton Ocean Model (POM). A few first applications of this methodology are presented in this paper. These include the BC meandering, the BC-eddy interaction and the meander-eddy-upwelling system (MEUS) simulations. Preliminary validation results include realistic wave-growth and eddy formation and sustained upwelling. Our future plan includes the application of these feature models with satellite, in-situ data and advanced data-assimilation schemes for nowcasting and forecasting the SEBRA region. (c) 2008 Elsevier Ltd. All rights reserved.

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The great similarities in the external morphologies and the lack of knowledge on ontogenetic and intersexual differences of species in the ariid genus Cathorops Jordan and Gilbert, 1882, has led to an abundance of misidentifications, causing great nomenclatural instability. Accordingly, the taxonomic statuses of the Cathorops species described from Eastern Pacific have remained controversial in the literature, even in recent studies. Here, we describe Cathorops raredonae, a new species from Mesoamerica (Mexico to El Salvador) and redescribe (in Cathorops) Tachysurus liropus Bristol, 1897, and Arius taylori Hildebrand, 1925, often listed as junior synonyms of Cathorops fuerthii (Steindachner, 1877) and Cathorops steindachneri (Gilbert and Starks, 1904), respectively, or treated as species inquirendae in Cathorops. We also redescribe and redefine the circumscriptions of C. fuerthii and C. steindachneri. Finally, we summarize current statuses of nominal species of Cathorops from the Eastern Pacific and provide an artificial key to identify the valid Pacific species.

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Introduction: Reductions in the prevalence of hepatitis B virus (HBV) infection and carriage, decreases in liver cancer incidence, and changes in patterns of liver dysfunctions are described after hepatitis B vaccination. Methods: We conducted a population-based seroprevalence study aimed at estimating the HBV prevalence and risk of infection in the rural area of Labrea following nineteen years of HBV vaccination. Results: Half of the subjects showed total anti-HBc of 52.1% (95% CI 49.6-54.7). The HBsAg prevalence was 6.2% (95% CI 5.1-7.6). Multivariate analysis showed an inverse association between HBV infection and vaccination (OR 0.62; 95% CI 0.44-0.87). HBsAg remained independently associated with past hepatitis (OR 2.44; 95% CI 1.52-3.89) and inversely to vaccination (OR 0.43; 95% CI 0.27-0.69). The prevalence of HBeAg among HBsAg-positive individuals was 20.4% (95% CI 12.8-30.1), with the positive subjects having a median age of 11 years (1-46) p=0.0003. Conclusions: We demonstrate that HBV infection is still an important public health issue and that HBV vaccination could have had better impact on HBV epidemiology. If we extrapolate these findings to other rural areas in the Brazilian Amazon, we can predict that the sources of chronic infected patients remain a challenge. Future studies are needed regarding clinical aspects, molecular epidemiology, surveillance of acute cases, and risk groups.

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The basement rock of the Pampean flat-slab (Sierras Pampeanas) in the Central Andes was uplifted and rotated in the Cenozoic era. The Western Sierras Pampeanas are characterised by meta-igneous rocks of Grenvillian Mesoproterozoic age and metasedimentary units metamorphosed in the Ordovician period. These rocks, known as the northern Cuyania composite terrane, were derived from Laurentia and accreted toward Western Gondwana during the Early Paleozoic. The Sierra de Umango is the westernmost range of the Western Sierras Pampeanas.This range is bounded by the Devonian sedimentary rocks of the Precordillera on the western side and Tertiary rocks from the Sierra de Maz and Sierra del Espinal on the eastern side and contains igneous and sedimentary rocks outcroppings from the Famatina System on the far eastern side. The Sierra de Umango evolved during a period of polyphase tectonic activity, including an Ordovician collisional event, a Devonian compressional deformation, Late Paleozoic and Mesozoic extensional faulting and sedimentation (Paganzo and Ischigualasto basins) and compressional deformation of the Andean foreland during the Cenozoic. A Nappe System and an important shear zone, La Puntilla-La Falda Shear Zone (PFSZ), characterise the Ordovician collisional event, which was related to the accretion of Cuyania Terrane to the proto-Andean margin of Gondwana. Three continuous deformational phases are recognised for this event: the D1 phase is distinguished by relics of 51 preserved as internal foliation within interkinematic staurolite por-phyroblasts and likely represents the progressive metamorphic stage; the D2 phase exhibits P-T conditions close to the metamorphic peak that were recorded in an 52 transposition or a mylonitic foliation and determine the main structure of Umango; and the D3 phase is described as a set of tight to recumbent folds with S3 axial plane foliation, often related to thrust faults, indicating the retrogressive metamorphic stage. The Nappe System shows a top-to-the S/SW sense direction of movement, and the PFSZ served as a right lateral ramp in the exhumation process. This structural pattern is indicative of an oblique collision, with the Cuyania Terrane subducting under the proto-Andean margin of Gondwana in the NE direction. This continental subduction and exhumation lasted at least 30 million years, nearly the entire Ordovician period, and produced metamorphic conditions of upper amphibolite-to-granulite facies in medium- to high-pressure regimes. At least two later events deformed the earlier structures: D4 and D5 deformational phases. The D4 deformational phase corresponds to upright folding, with wavelengths of approximately 10 km and a general N-S orientation. These folds modified the S2 surface in an approximately cylindrical manner and are associated with exposed, discrete shear zones in the Silurian Guandacolinos Granite. The cylindrical pattern and subhorizontal axis of the D4 folds indicates that the S2 surface was originally flat-lying. The D4 folds are responsible for preserving the basement unit Juchi Orthogneiss synformal klippen. This deformation corresponds to the Chanica Tectonic during the interval between the Devonian and Carboniferous periods. The D5 deformational phase comprehends cuspate-lobate shaped open plunging folds with E W high-angle axes (D5 folds) and sub-vertical spaced cleavage. The D5 folds and related spaced cleavage deformed the previous structures and could be associated with uplifting during the Andean Cycle. (C) 2012 Elsevier Ltd. All rights reserved.

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Introduction: The aim of this work was to identify possible lymphatic filariasis foci in the western Brazilian Amazonian that could be established from the reports of Rachou in the 1950s. The study was conducted in three cities of the western Brazilian Amazon region - Porto Velho and Guajará-Mirim (State of Rondônia) and Humaitá (State of Amazonas). Methods: For human infection evaluation thick blood smear stained with Giemsa was used to analyze samples collected from 10pm to 1am. Polymerase chain reaction (PCR) was used to examine mosquito vectors for the presence of Wuchereria bancrofti DNA. Humans were randomly sampled from night schools students and from inhabitants in neighborhoods lacking sanitation. Mosquitoes were collected from residences only. Results: A total 2,709 night students enrolled in the Program for Education of Young Adults (EJA), and 935 people registered in the residences near the schools were examined, being 641 from Porto Velho, 214 from Guajará-Mirim and 80 from Humaitá. No individual examined was positive for the presence of microfilariae in the blood stream. A total of 7,860 female Culex quinquefasciatus specimens examined were negative by PCR. Conclusions: This survey including human and mosquito examinations indicates that the western Amazon region of Brazil is not a focus of Bancroftian filariasis infection or transmission. Therefore, there is no need to be included in the Brazilian lymphatic filariasis control program.

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This thesis focusses on the tectonic evolution and geochronology of part of the Kaoko orogen, which is part of a network of Pan-African orogenic belts in NW Namibia. By combining geochemical, isotopic and structural analysis, the aim was to gain more information about how and when the Kaoko Belt formed. The first chapter gives a general overview of the studied area and the second one describes the basis of the Electron Probe Microanalysis dating method. The reworking of Palaeo- to Mesoproterozoic basement during the Pan-African orogeny as part of the assembly of West Gondwana is discussed in Chapter 3. In the study area, high-grade rocks occupy a large area, and the belt is marked by several large-scale structural discontinuities. The two major discontinuities, the Sesfontein Thrust (ST) and the Puros Shear Zone (PSZ), subdivide the orogen into three tectonic units: the Eastern Kaoko Zone (EKZ), the Central Kaoko Zone (CKZ) and the Western Kaoko Zone (WKZ). An important lineament, the Village Mylonite Zone (VMZ), has been identified in the WKZ. Since plutonic rocks play an important role in understanding the evolution of a mountain belt, zircons from granitoid gneisses were dated by conventional U-Pb, SHRIMP and Pb-Pb techniques to identify different age provinces. Four different age provinces were recognized within the Central and Western part of the belt, which occur in different structural positions. The VMZ seems to mark the limit between Pan-African granitic rocks east of the lineament and Palaeo- to Mesoproterozoic basement to the west. In Chapter 4 the tectonic processes are discussed that led to the Neoproterozoic architecture of the orogen. The data suggest that the Kaoko Belt experienced three main phases of deformation, D1-D3, during the Pan-African orogeny. Early structures in the central part of the study area indicate that the initial stage of collision was governed by underthrusting of the medium-grade Central Kaoko zone below the high-grade Western Kaoko zone, resulting in the development of an inverted metamorphic gradient. The early structures were overprinted by a second phase D2, which was associated with the development of the PSZ and extensive partial melting and intrusion of ~550 Ma granitic bodies in the high-grade WKZ. Transcurrent deformation continued during cooling of the entire belt, giving rise to the localized low-temperature VMZ that separates a segment of elevated Mesoproterozoic basement from the rest of the Western zone in which only Pan-African ages have so far been observed. The data suggest that the boundary between the Western and Central Kaoko zones represents a modified thrust zone, controlling the tectonic evolution of the Kaoko belt. The geodynamic evolution and the processes that generated this belt system are discussed in Chapter 5. Nd mean crustal residence ages of granitoid rocks permit subdivision of the belt into four provinces. Province I is characterised by mean crustal residence ages <1.7 Ga and is restricted to the Neoproterozoic granitoids. A wide range of initial Sr isotopic values (87Sr/86Sri = 0.7075 to 0.7225) suggests heterogeneous sources for these granitoids. The second province consists of Mesoproterozoic (1516-1448 Ma) and late Palaeo-proterozoic (1776-1701 Ma) rocks and is probably related to the Eburnian cycle with Nd model ages of 1.8-2.2 Ga. The eNd i values of these granitoids are around zero and suggest a predominantly juvenile source. Late Archaean and middle Palaeoproterozoic rocks with model ages of 2.5 to 2.8 Ga make up Province III in the central part of the belt and are distinct from two early Proterozoic samples taken near the PSZ which show even older TDM ages of ~3.3 Ga (Province IV). There is no clear geological evidence for the involvement of oceanic lithosphere in the formation of the Kaoko-Dom Feliciano orogen. Chapter 6 presents the results of isotopic analyses of garnet porphyroblasts from high-grade meta-igneous and metasedimentary rocks of the sillimanite-K-feldspar zone. Minimum P-T conditions for peak metamorphism were calculated at 731±10 °C at 6.7±1.2 kbar, substantially lower than those previously reported. A Sm-Nd garnet-whole rock errorchron obtained on a single meta-igneous rock yielded an unexpectedly old age of 692±13 Ma, which is interpreted as an inherited metamorphic age reflecting an early Pan-African granulite-facies event. The dated garnets survived a younger high-grade metamorphism that occurred between ca. 570 and 520 Ma and apparently maintained their old Sm-Nd isotopic systematics, implying that the closure temperature for garnet in this sample was higher than 730 °C. The metamorphic peak of the younger event was dated by electronmicroprobe on monazite at 567±5 Ma. From a regional viewpoint, it is possible that these granulites of igneous origin may be unrelated to the early Pan-African metamorphic evolution of the Kaoko Belt and may represent a previously unrecognised exotic terrane.

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It is lively debated how eclogites find their way from deep to mid-crustal levels during exhumation. Different exhumation models for high-pressure and ultrahigh-pressure rocks were suggested in previous studies, based mainly on field observations and less on microstructural studies on the exhumed rocks. The development and improvement of electron microscopy techniques allows it, to focus interest on direct investigations of microstructures and crystallographic properties in eclogites. In this case, it is of importance to study the applicability of crystallographic measurements on eclogites for exhumation processes and to unravel which processes affect eclogite textures. Previous studies suggested a strong relationship between deformation and lattice preferred orientation (LPO) in omphacite but it is still unclear if the deformation is related to the exhumation of eclogites. This study is focused on the questions which processes affect omphacite LPO and if textural investigations of omphacite are applicable for studying eclogite exhumation. Therefore, eclogites from two examples in the Alps and in the Caledonides were collected systematically and investigated with respect to omphacite LPO by using the electron backscattered diffraction (EBSD) technique. Omphacite textures of the Tauern Window (Austria) and the Western Gneiss Region (Norway) were studied to compare lattice preferred orientation with field observations and suggested exhumation models from previous studies. The interpretation of omphacite textures, regarding the deformation regime is mainly based on numerical simulations in previous studies. Omphacite LPO patterns of the Eclogite Zone are clearly independent from any kind of exhumation process. The textures were generated during omphacite growth on the prograde path of eclogite development until metamorphic peak conditions. Field observations in the Eclogite Zone show that kinematics in garnet mica schist, surrounding the eclogites, strongly indicate an extrusion wedge geometry. Stretching lineations show top-N thrusting at the base and a top-S normal faulting with a sinistral shear component at the top of the Eclogite Zone. The different shear sense on both sides of the unit does not affect the omphacite textures in any way. The omphacite lattice preferred orientation patterns of the Western Gneiss Region can not be connected with any exhumation model. The textures were probably generated during the metamorphic peak and reflect the change from subduction to exhumation. Eclogite Zone and Western Gneiss Region differ significantly in size and especially in metamorphic conditions. While the Eclogite Zone is characterized by constant P-T conditions (600-650°C, 20-25 kbar), the Western Gneiss Region contains a wide P-T range from high- to ultrahigh pressure conditions (400-800°C, 20-35 kbar). In contrast to this, the omphacite textures of both units are very similar. This means that omphacite LPO is independent from P-T conditions and therefore from burial depth. Further, in both units, omphacite LPO is independent from grain and subgrain size as well as from any shape preferred orientation (SPO) on grain and subgrain scale. Overall, omphacite lattice preferred orientation are generated on the prograde part of omphacite development. Therefore, textural investigations on omphacite LPO are not applicable to study eclogite exhumation.

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Bivalve mollusk shells are useful tools for multi-species and multi-proxy paleoenvironmental reconstructions with a high temporal and spatial resolution. Past environmental conditions can be reconstructed from shell growth and stable oxygen and carbon isotope ratios, which present an archive for temperature, freshwater fluxes and primary productivity. The purpose of this thesis is the reconstruction of Holocene climate and environmental variations in the North Pacific with a high spatial and temporal resolution using marine bivalve shells. This thesis focuses on several different Holocene time periods and multiple regions in the North Pacific, including: Japan, Alaska (AK), British Columbia (BC) and Washington State, which are affected by the monsoon, Pacific Decadal Oscillation (PDO) and El Niño/Southern Oscillation (ENSO). Such high-resolution proxy data from the marine realm of mid- and high-latitudes are still rare. Therefore, this study contributes to the optimization and verification of climate models. However, before using bivalves for environmental reconstructions and seasonality studies, life history traits must be well studied to temporally align and interpret the geochemical record. These calibration studies are essential to ascertain the usefulness of selected bivalve species as paleoclimate proxy archives. This work focuses on two bivalve species, the short-lived Saxidomus gigantea and the long-lived Panopea abrupta. Sclerochronology and oxygen isotope ratios of different shell layers of P. abrupta were studied in order to test the reliability of this species as a climate archive. The annual increments are clearly discernable in umbonal shell portions and the increments widths should be measured in these shell portions. A reliable reconstruction of paleotemperatures may only be achieved by exclusively sampling the outer shell layer of multiple contemporaneous specimens. Life history traits (e.g., timing of growth line formation, duration of the growing season and growth rates) and stable isotope ratios of recent S. gigantea from AK and BC were analyzed in detail. Furthermore, a growth-temperature model based on S. gigantea shells from Alaska was established, which provides a better understanding of the hydrological changes related to the Alaska Coastal Current (ACC). This approach allows the independent measurement of water temperature and salinity from variations in the width of lunar daily growth increments of S. gigantea. Temperature explains 70% of the variability in shell growth. The model was calibrated and tested with modern shells and then applied to archaeological specimens. The time period between 988 and 1447 cal yrs BP was characterized by colder (~1-2°C) and much drier (2-5 PSU) summers, and a likely much slower flowing ACC than at present. In contrast, the summers during the time interval of 599-1014 cal yrs BP were colder (up to 3°C) and fresher (1-2 PSU) than today. The Aleutian Low may have been stronger and the ACC was probably flowing faster during this time.

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Agriculture is still important for socio-economic development in rural areas of Bosnia, Montenegro and Serbia (BMS). However, for sustainable rural development rural economies should be diversified so attention should be paid also to off-farm and non-farm income-generating activities. Agricultural and rural development (ARD) processes and farm activity diversification initiatives should be well governed. The ultimate objective of this work is to explore linkages between ARD governance and rural livelihoods diversification in BMS. The thesis is based on an extended secondary data analysis and surveys. Questionnaires for ARD governance and coordination were sent via email to public, civil society and international organizations. Concerning rural livelihood diversification, the field questionnaire surveys were carried out in three rural regions of BMS. Results show that local rural livelihoods are increasingly diversified but a significant share of households are still engaged in agriculture. Diversification strategies have a chance to succeed taking into consideration the three rural regions’ assets. However, rural households have to tackle many problems for developing new income-generating activities such as the lack of financial resources. Weak business skills are also a limiting factor. Fully exploiting rural economy diversification potential in BMS requires many interventions including improving rural governance, enhancing service delivery in rural areas, upgrading rural people’s human capital, strengthening rural social capital and improving physical capital, access of the rural population to finance as well as creating a favourable and enabling legal and legislative environment fostering diversification. Governance and coordination of ARD policy design, implementation and evaluation is still challenging in the three Balkan countries and this has repercussions also on the pace of rural livelihoods diversification. Therefore, there is a strong and urgent need for mobilization of all rural stakeholders and actors through appropriate governance arrangements in order to foster rural livelihoods diversification and quality of life improvement.

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This study presents geo-scientific evidence for Holocene tsunami impact along the shores of the Eastern Ionian Sea. Cefalonia Island, the Gulf of Kyparissia and the Gialova Lagoon were subject of detailed geo-scientific investigations. It is well known that the coasts of the eastern Mediterranean were hit by the destructive influence of tsunamis in the past. The seismically highly active Hellenic Trench is considered as the most significant tsunami source in the Eastern Ionian Sea. This study focuses on the reconstruction and detection of sedimentary signatures of palaeotsunami events and their influence on the Holocene palaeogeographical evolution. The results of fine grained near coast geo-archives are discussed and interpreted in detail to differentiate between tsunami, storm and sea level highstands as sedimentation processes.rnA multi-method approach was applied using geomorphological, sedimentological, geochemical, geophysical and microfaunal analyses to detect Holocene tsunamigenic impact. Chronological data were based on radiocarbondatings and archaeological age estimations to reconstruct local geo-chronostratigraphies and to correlate them on supra-regional scales.rnDistinct sedimentary signatures of 5 generations of tsunami impact were found along the coasts of Cefalonia in the Livadi coastal plain. The results show that the overall coastal evolution was influenced by tsunamigenic impact that occured around 5700 cal BC (I), 4250 cal BC (II), at the beginning of the 2nd millennium cal BC (III), in the 1st millennium cal BC (IV) and posterior to 780 cal AD (V). Sea level reconstructions and the palaeogeographical evolution show that the local Holocene sea level has never been higher than at present.rnAt the former Mouria Lagoon along the Gulf of Kyparissia almost four allochtonous layers of tsunamigenic origin were identified. The stratigraphical record and palaeogeographical reconstructions show that major environmental coastal changes were linked to these extreme events. At the southern end of the Agoulenitsa Lagoon at modern Kato Samikon high-energy traces were found more than 2 km inland and upt ot 9 m above present sea level. The geo-chronological framework deciphered tsunami landfall for the 5th millennium cal BC (I), mid to late 2nd mill. BC (II), Roman times (1st cent. BC to early 4th cent. AD) (III) and most possible one of the historically well-known 365 AD or 521/551 AD tsunamis (IV).rnCoarse-grained allochthonous sediments of marine origin were found intersecting muddy deposits of the quisecent sediments of the Gialova Lagoon on the southwestern Peloponnese. Radiocarbondatings suggest 6 generations of major tsunami impact. Tsunami generations were dated to around 3300 cal BC (I), around the end of 4th and the beginning of 3rd millennium BC (II), after around 1100 cal BC (III), after the 4th to 2nd cent. BC (IV), between the 8th and early 15th cent. AD (V) and between the mid 14th to beginning of 15th cent. AD (VI). Palaeogeographical and morphological characteristics in the environs of the Gialova Lagoon were controlled by high-energy influence.rnSedimentary findings in all study areas are in good accordance to traces of tsunami events found all over the Ionian Sea. The correlation of geo-chronological data fits very well to coastal Akarnania, the western Peloponnese and finding along the coasts of southern Italy and the Aegean. Supra-regional influence of tsunamigenic impact significant for the investigated sites. The palaeogeographical evolution and palaeo-geomorphological setting of the each study area was strongly affected by tsunamigenic impact.rnThe selected geo-archives represent extraordinary sediment traps for the reconstruction of Holocene coastal evolution. Our result therefore give new insight to the exceptional high tsunami risk in the eastern Mediterranean and emphasize the underestimation of the overall tsunami hazard.

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Der Fokus dieser Dissertation ist die populationsgenetische Analyse der neolithischen Bevölkerungswechsel in den 6.-5. Jahrtausende vor Christus, die im westlichen Karpatenbecken stattfanden. Die Zielsetzung der Studie war, mittels der Analyse von mitochondrialer und Y-chromosomaler aDNA, den Genpool der sechs neolithischen und kupferzeitlichen Populationen zu untersuchen und die daraus resultierenden Ergebnisse mit anderen prähistorischen und modernen genetischen Daten zu vergleichen.rnInsgesamt wurden 323 Individuen aus 32 ungarischen, kroatischen und slowakischen Fundplätzen beprobt und bearbeitet in den archäogenetischen Laboren der Johannes Gutenberg-Universität in Mainz. Die DNA Ergebnisse wurden mit verschiedenen populationsgenetischen Methoden ausgewertet. Vergleichsdaten von prähistorischen und modernen eurasiatischen Populationen wurden dazu gesammelt.rnDie HVS-I Region der mitochondrialen DNA konnten bei 256 Individuen reproduziert und authentifiziert werden (mit einer Erfolgsrate von 85.9%). Die Typisierung der HVS-II Region war in 80 Fällen erfolgreich. Testend alle gut erhaltene Proben, die Y-chromosomale Haplogruppe konnte in 33 männlichen Individuen typisiert werden.rnDie neolithischen, mitochondrialen Haplogruppen deuten auf eine hohe Variabilität des maternalen Genpools hin. Sowohl die mitochondrialen als auch die Y-chromosomalen Daten lassen Rückschlüsse auf eine nah-östliche bzw. südwestasiatische Herkunft der frühen Bauern zu. Die Starčevo- und linearbandkermaischen-Populationen in westlichem Karpatenbecken (letztere abgekürzt als LBKT) und die linearbandkermaischen-Population in Mitteleuropa (LBK) haben so starke genetische Ähnlichkeit, dass die Verbreitung der LBK nach Mitteleuropa mit vorangegangenen Wanderungsereignissen zu erklären ist. Die Transdanubische aDNA Daten zeigen hohe Affinität zu den publizierten prähistorischen aDNA Datensätzen von Mitteleuropa aus den 6.-4. Jahrtausende vor Chr. Die maternal-genetische Variabilität der Starčevo-Population konnte auch innerhalb der nachfolgenden Populationen Transdanubiens festgestellt werden. Nur kleinere Infiltrationen und Immigrationsereignissen konnten während der Vinča-, LBKT-, Sopot- und Balaton-Lasinja-Kultur in Transdanubien identifiziert werden. Zwischen den transdanubischen Regionen konnten mögliche genetische Unterschiede nur in der LBKT und in der Lengyel-Periode beobachtet werden, als sich die nördlichen Gruppen von den südlichen Populationen trennten. rnDie festgestellte Heterogenität der mtDNA in Zusammenhang mit der Y-chromosomalen Homogenität in den Starčevo- und LBK-Populationen, weisen auf patrilokale Residenzregeln und patrilineare Abstammungsregeln in den ersten Bauergemeinschaften hin. rnObwohl die hier präsentierten Daten einen großen Fortschritt in der Forschung von aDNA und Neolithikum des Karpatenbeckens und Mitteleuropas bedeuten, werfen sie auch mehrere Fragen auf, deren Beantwortung durch zukünftige Genomforschungen erbracht werden könnte.

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Due to its environmental, safety, health and socio-economic impacts, marine litter has been recognized as a 21st century global challenge, so that it has been included in Descriptor 10 of the EU MSFD. For its morphological features and anthropogenic pressures, the Adriatic Sea is very sensitive to the accumulation of debris, but data are inconsistent and fragmented. This thesis, in the framework of DeFishGear project, intents to assess marine litter on beaches and on seafloor in the Western Adriatic sea, and test if debris ingestion by fish occurs. Three beaches were sampled during two surveys in 2015. Benthic litter monitoring was carried out in the FAO GSA17 during fall 2014, using a rapido trawl. Litter ingestion was investigated through gut contents analysis of 260 fish belonging to 8 commercial species collected in Western Gulf of Venice. Average litter density on beaches was 1.5 items/m2 during spring, and decreased to 0.8 items/m2 in summer. Litter composition was heterogeneous and varied among sites, even if no significant differences were found. Most of debris consisted of plastic sheets, fragments, polystyrene pieces, mussels nets and cottons bud sticks, showing that sources are many and include aquaculture, land-based activities and local users of beaches. Average density of benthic litter was 913 items/Km2 (82 Kg/Km2). Plastic dominated in terms of numbers and weight, and consisted mainly of bags, sheets and mussel nets. The highest density was found close to the coast, and sources driving the major differences in litter distribution were mussel farms and shipping lanes. Litter ingestion occurred in 47% of examined fish, mainly consisting of fibers. Among species, S. pilchardus swallowed almost all debris categories. Findinds may provide a baseline to set the necessary measures to manage and minimize marine litter in the Western Adriatic region and to protect aquatic life from plastic pollution, even accounting the possible implications on human health.

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Extension of 3-D atmospheric data products back into the past is desirable for a wide range of applications. Historical upper-air data are important in this endeavour, particularly in the maritime regions of the tropics and the southern hemisphere, where observations are extremely sparse. Here we present newly digitized and re-evaluated early ship-based upper-air data from two cruises: (1) kite and registering balloon profiles from onboard the ship SMS Planet on a cruise from Europe around South Africa and across the Indian Ocean to the western Pacific in 1906/1907, and (2) ship-based radiosonde data from onboard the MS Schwabenland on a cruise from Europe across the Atlantic to Antarctica and back in 1938/1939. We describe the data and provide estimations of the errors. We compare the data with a recent reanalysis (the Twentieth Century Reanalysis Project, 20CR, Compo et al., 2011) that provides global 3-D data back to the 19th century based on an assimilation of surface pressure data only (plus monthly mean sea-surface temperatures). In cruise (1), the agreement is generally good, but large temperature differences appear during a period with a strong inversion. In cruise (2), after a subset of the data are corrected, close agreement between observations and 20CR is found for geopotential height (GPH) and temperature notwithstanding a likely cold bias of 20CR at the tropopause level. Results are considerably worse for relative humidity, which was reportedly inaccurately measured. Note that comparing 20CR, which has limited skill in the tropical regions, with measurements from ships in remote regions made under sometimes difficult conditions can be considered a worst case assessment. In view of that fact, the anomaly correlations for temperature of 0.3–0.6 in the lower troposphere in cruise (1) and of 0.5–0.7 for tropospheric temperature and GPH in cruise (2) are considered as promising results. Moreover, they are consistent with the error estimations. The results suggest room for further improvement of data products in remote regions.