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911.
Susanne Jahns 《Vegetation History and Archaeobotany》2007,16(2-3):157-169
A Late Pleistocene and Holocene sediment core from the nowadays terrestrialised portion of the Löddigsee in Southern Mecklenburg, Germany was palynologically investigated. The lake is situated in the rarely investigated Young moraine area at the transition from the Weichselian to the Saalian glaciation. The high-resolution pollen diagram contributes to the establishment of the north-eastern German Late Pleistocene pollen stratigraphy. The vegetation distribution pattern after the end of the Weichselian is in good agreement with other studies from North-eastern Germany, but also has its own characteristics. The Holocene vegetation development reveals features from the north-eastern and north-western German lowlands. A special focus was laid on the environmental history of the two settlements on an island within the lake (Late Neolithic and Younger Slavic period), which were preserved under moist conditions. Both settlements were constructed during a period of low lake level. Although there is evidence of agriculture in the area during the respective periods, the two island settlements seem to have served other purposes. 相似文献
912.
Abstract. The results of pollen analysis and radiocarbon dating are presented from three northern Apennine sequences; Lago Padule in northern Tuscany and Lago Pratignano and Ospitale in the Emilia-Romagnan Apennines. This is the first detailed pollen stratigraphic information from sites in Emilia-Romagna and north Tuscany and extends eastwards the area from which information on vegetational history is available. The sequence from Lago Padule is one of the most complete Holocene records known from the northern Apennine region. Lago Pratignano has the deepest sequence of organic sediments (1544 cm) and the fastest rates of sediment accumulation (up to 28 cm per 100 years) providing the highest resolution record for the mid to late Holocene periods in the region. High rates of sedimentation have also occurred at Ospitale where organic sediments are 780 cm deep and began to form at approximately 5500 bp. The record from Lago Padule is compared with Holocene records from two nearby sites and a series of Regional Pollen Assemblage Zones is defined for the eastern area of the northern Apennines. The main features of vegetational change identified are: (i) a‘pioneer’phase of rapid forest development during the early Holocene followed by the establishment of an upper forest belt dominated by Abies, and a belt of mixed deciduous forest at lower altitudes; (ii) the appearance and rapid expansion of Fagus between approximately 5200 bp and 2900 bp forming a mixed Abies-Fagus association in the upper forest belt; and (iii) the overall reduction of forest cover, and dominance of Fagus in the arboreal vegetation from around 2900 bp. The scheme of Regional PAZs for the eastern area is used as a framework for the review of pollen stratigraphic information and radiocarbon dates from other sites in the northern Apennine region. Characteristics of pollen records which can be identified in sequences from across the region are identified and the chronology of similar changes in pollen stratigraphy is examined. The scheme of four regional PAZs for the Holocene period is shown to be valid for the entire northern Apennine region. The examination of a series of pollen records shows that Fagus appeared earlier in the western than the eastern part of the region during the mid Holocene and became dominant in the northern Apennine forests post 3000 bp. The impact of anthropogenic activity and climatic change on the spread and development of Fagus are discussed. The palynological evidence which is now available from the northern Apennines is compared with information for the region shown in the‘European pollen maps’of Huntley & Birks (1983). This study provides an updated review of the representation of different tree taxa in Holocene pollen records from the northern Apennines and illustrates the role of the northern Apennines as a refugium for trees during the Wurmian Lateglacial. 相似文献
913.
914.
《Endocrine practice》2021,27(5):390-395
ObjectiveTo examine temporal changes in the number and demographic composition of transgender/gender non-binary (TGNB) population using data from integrated health care systems.MethodsElectronic health records from Kaiser Permanente health plans in Georgia and Northern and Southern California were used to identify TGNB individuals, who sought care from January 2006 to December 2014, and the data were analyzed by year, site, age, and sex assigned at birth.ResultsIn 2006, the number of TGNB people (and corresponding 95% CI) per 100 000 population were 3.5 (1.9, 6.3) in Georgia, 5.5 (4.8, 6.4) in Southern California, and 17 (16, 19) in Northern California. In 2014, these frequencies increased to 38 (32, 45), 44 (42, 46), and 75 (72, 78) per 100 000 population, respectively. When analyzed by age, the most rapid increase was observed among persons 18 to 25 years old, and this increase accelerated after 2010. The ratio of transmasculine to transfeminine persons also changed from 1:1.7 in 2006 to 1:1 in 2014 overall and from 1:1 in 2006 to 1.8:1 in 2014 among persons <18 years of age.ConclusionThis analysis confirms previous observations that the proportion of TGNB people is growing, especially among young adults. The composition of the TGNB population is also changing from predominantly transfeminine to roughly 1:1 overall and to predominantly transmasculine in children and adolescents. 相似文献
915.
The first δ18O and δ13C data from the Upper Jurassic of the Northern Calcareous Alps are presented. The interpretation of stable isotope ratios serves as an approach for paleoenvironmental and diagenetic studies of the Plassen carbonate platform, which cannot be obtained by paleontological methods and microfacies analyses alone. The studied part of the Plassen limestone is characterized by (1) lithoclast facies, also called ‘intraformational breccia’; the origin of lithoclasts was formerly unknown; (2) peloid facies; (3) bioclastic facies, composed of peloids, porostromate algae, green algae and red algae; and (4) oncoid facies. Two types of fracturing and four cement generations can be distinguished. Isotope ratios of the matrix, oncoids, three cement generations and whole rock samples revealed that (1) the studied section represents an open marine carbonate platform with high water circulation and high input of cool oceanic waters; (2) the platform was not affected by emersion and fresh water influence; normal marine conditions prevailed; (3) carbonate cements were precipitated in a closed diagenetic system, but burial diagenesis was absent; (4) both fabric-selective and non-fabric-selective fracturing occurred in a normal marine environment, affecting the formation of ‘intraformational breccias’. 相似文献
916.
Dorottya Bognar-Lahr 《Ocean Development & International Law》2020,51(2):143-161
AbstractIn the field of Arctic shipping, Canada and the Russian Federation have enacted extensive unilateral national regulations cognizant of Article 234, UN Convention on the Law of the Sea. On the global level, both states have been important actors in negotiating the International Maritime Organization’s mandatory Polar Code, a legal instrument with implications for regulations at the national level. This article compares and contrasts the approaches, positions, and arguments of Canada and Russia especially regarding national systems to control navigation and vessel-source pollution. The results suggest different emphases stemming from the two states’ political and economic realities and capacities. 相似文献
917.
An actin-related protein (ACLA) has been identified in the cellular slime mould Dictyostelium discoideum. The complete cDNA sequence indicates that within the actin superfamily it belongs to the ARP3 family of actin-related proteins together with Arp66B from Drosophila melanogaster, Actin2 from Bos taurus, act2 from Schizosaccharomyces pombe and possibly act2 from Caenorhabditis elegans. The ACLA mRNA is regulated during development, showing a maximum between 2 and 4 h after starvation. The protein has been expressed in E. coli and antibodies raised against it. Immunofluorescence microscopy shows that ACLA protein co-localises with mitochondria; the protein co-purifies with Dictyostelium mitochondria. 相似文献
918.