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Contemporary precipitation patterns in the Caribbean region are spatially variable, and the small number of Holocene paleoclimatic records may not adequately capture patterns of variation in the past. The hydrological history of Grenada was inferred from paleolimnological analyses of sediment cores from two crater lakes on the island. The basins were formed by volcanic activity some time during th

Vegetation dynamics during the earliest part of the Holocene (11,250-10,250 cal yr BP) have been reconstructed from a lacustrine sequence on Sandoy, the Faroe Islands, using detailed plant macrofossil and pollen evidence. The plant macrofossils suggest the initial vegetation was sparse herb and shrub tundra, with Salix herbacea and open-ground species, followed by the development of a denser and m

The Amazon is one of the few continental regions where atmospheric aerosol particles and their effects on climate are not dominated by anthropogenic sources. During the wet season, the ambient conditions approach those of the pristine pre-industrial era. We show that the fine submicrometer particles accounting for most cloud condensation nuclei are predominantly composed of secondary organic mater

Isla de los Estados is a mountainous island southeast of Tierra del Fuego, in southernmost South America. Its central and eastern parts have an alpine topography, transected by U-shaped valleys, small, partly over-deepened fjords, and a multitude of abandoned cirques, all associated with extensive former local glaciations. Traces of glacial erosion generally reach 400-450 m a.s.l., and above that

Pollen accumulation rates (PARs) provide a potential proxy for quantitative tree volume (m3 ha-1) reconstruction with reliable absolute pollen productivity estimates (APPEs). We obtained APPEs for pine, spruce and birch at their range limits in northern Finland under two temperature periods (warm and cold) based on long-term pollen trap and tree volume records within a 14-km radius of each trap. A

Atmospheric aerosol particles have substantial influence on climate and air quality. However, the anthropogenic influence on the atmospheric aerosol is still poorly known. This limits the understanding of past and future climate changes. Additionally, both epidemiological and toxicological studies indicate adverse health effects of inhaled aerosol particles. In order to study the effect of atmosph

In this paper, we present a method of constructing new families of LDPC block code ensembles formed by terminating irregular protograph-based LDPC convolutional codes. Using the accumulate-repeat-by-4-jagged-accumulate (AR4JA) protograph as an example, a density evolution analysis for the binary erasure channel shows that this flexible design technique gives rise to a large selection of LDPC block

Decision-making in requirements engineering often needs to be done in the presence of uncertainty. Rigorous methods can help to increase the probability of making the most appropriate decisions under the given circumstances. Robustness is a measure for the degree of stability of a solution in case of changes in the problem parameters. This paper presents a method (called DECIDERelease) that applie

Product codes, due to their relatively large minimum distance, are often seen as a natural solution for applications requiring low error floors. In this paper, we show by means of an ensemble weight enumerator analysis that the minimum distance multiplicities of product codes are much higher than those obtainable by other generalized LDPC (GLDPC) constructions employing the same component codes. W

Accurately reconstructing the rate of movement and extent of eolian dunes over thousands of years is a challenging endeavor. In this paper, we refine the methodology for utilizing lakes and bogs downwind of dune fields as precise recorders of past eolian activity. Sediment cores from two Allegan County lakes and one bog associated with dunes were studied to evaluate the importance of the various s

Generalized Frequency Division Multiplexing (GFDM) is a recent multi carrier modulation technique that can provide low out-of-band radiation, which makes it an attractive choice for the PHY layer of cognitive radios operating in fragmented TV white spaces. Primary, incumbent signals can now be protected with a geo-location database query mechanism. Even then, sensing opportunistic users (OU) opera

Isla de los Estados (54A degrees 45'S, 63A degrees 10'aEuro"64A degrees 46'W) lies east of the main island of Tierra del Fuego and is the southeastern-most point in Argentina. Because of its geographic position near the latitudes of the Southern Hemisphere Westerlies and the strong influence of the Antarctic Circumpolar Current (ACC), the area is suitable for paleoecological and paleoclimate resea

We compare LDPC block and LDPC convolutional codes with respect to their decoding performance under low decoding latencies. Protograph based regular LDPC codes are considered with rather small lifting factors. LDPC block and convolutional codes are decoded using belief propagation. For LDPC convolutional codes, a sliding window decoder with different window sizes is applied to continuously decode

The aim of this study was to assess whether a school-based program with expanded physical education lessons was effective in increasing children's physical capacity and in preventing excessive weight gain in children. The study performed in 2000-2003 comprised 132 children, 73 boys and 59 girls at baseline 6-9 years and in follow-up 9-12 years, attending two different schools with a similar size,

The topological characteristics of an IEEE 802.16 mesh network including the tree’s depth and degree of its nodes affect the delay and throughput of the network. To reach the desired trade-off between delay and throughput, all potential trees should be explored to obtain a tree with the proper topology. Since the number of extractable tree topologies from a given network graph is enormous, we use

A variety of palaeoclimatic records show a shift towards cooler, wetter and windier conditions in Europe around 2800 cal a BP. The shift broadly coincides with an increase of the atmospheric C-14 concentration, suggesting a connection between solar activity variations and climate change. Here we investigate a peat record from Undarsmosse in southern Sweden. In a previous study, based on a low-reso

We investigate a family of protograph based rate-compatible LDPC convolutional codes. The code family shows improved thresholds close to the Shannon limit compared to their uncoupled versions for the binary erasure channel as well as the AWGN channel. In fact, the gap to Shannon limit is almost uniform for all members of the code family ensuring good performance for all subsequent incremental redu

The relation between delta O-18 of precipitation and temperature has been used in numerous studies to reconstruct past temperatures at ice core sites in Greenland and Antarctica. During the past two decades, it has become clear that the slope between delta O-18 and temperature varies in both space and time. Here, we use a general circulation model driven by changes in orbital parameters to investi

The Civil Aircraft for the Regular Investigation of the Atmosphere Based on an Instrument Container (CARIBIC) project investigates physical and chemical processes in the Earth's atmosphere using a Lufthansa Airbus long-distance passenger aircraft. After the beginning of the explosive eruption of the Eyjafjallajokull volcano on Iceland on 14 April 2010, the first CARIBIC volcano-specific measuremen

Thermal-optical analysis is a conventional method for determining the carbonaceous aerosol fraction and for classifying it into organic carbon, OC, and elemental carbon, EC. Unfortunately, the different thermal evolution protocols in use can result in a wide elemental carbon-to-total carbon variation by up to a factor of five. In Europe, there is currently no standard procedure for determining the