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Rereading a tree-ring database to illustrate depositional histories of subfossil trees

Late Quaternary tree-ring chronologies have been constructed using data collected from subfossil trees preserved under favourable conditions in lake sediments and peat deposits. Tree-ring widths and densities are commonly used for reconstructions of past climate variability. An alternative way of using these data is to explore the replication curves of these chronologies. Here, we make use of prev

Impacts of regional climatic fluctuations on radial growth of Siberian and Scots pine at Mukhrino mire (central-western Siberia)

Ring width (TRW) chronologies from Siberian (Pinus sibirica) and Scots (Pinus sylvestris) pine trees were sampled at Mukhrino – a large mire complex in central-western Siberia – to evaluate the impacts of hydroclimatic variabil- ity on tree growth over the last three centuries. For this purpose, we compared climate-growth correlation pro- files from trees growing on peat soils with those growing oRing width (TRW) chronologies from Siberian (Pinus sibirica) and Scots (Pinus sylvestris) pine trees were sampled at Mukhrino - a large mire complex in central-western Siberia - to evaluate the impacts of hydroclimatic variability on tree growth over the last three centuries. For this purpose, we compared climate-growth correlation profiles from trees growing on peat soils with those growing on ad

Subfossil peatland trees as proxies for Holocene palaeohydrology and palaeoclimate

Due to the scarcity of reliable and highly resolved moisture proxies covering much of the Holocene, there has been increased interest in the study of living and subfossil peatland trees sensitive to gradual and extreme chang- es in hydrology, precipitation, and related environmental processes. Peatland development and the associated carbon accumulation, which are strongly influenced by hydrologicaDue to the scarcity of reliable and highly resolved moisture proxies covering much of the Holocene, there has been increased interest in the study of living and subfossil peatland trees sensitive to gradual and extreme changes in hydrology, precipitation, and related environmental processes. Peatland development and the associated carbon accumulation, which are strongly influenced by hydrological

Recent advances in long-term climate and moisture reconstructions from the Baltic region: Exploring the potential for a new multi- millennial tree-ring chronology

This study presents the first results from an ongoing initiative to develop a multi-millennial Baltic tree- ring width (TRW) chronology consisting of 12 floating records from subfossil Scots pines (Pinus sylvestris L.) extracted from three Lithuanian peat-mining areas. The floating series have been complemented with absolutely dated TRW chronologies which were obtained from living trees growing inThis study presents the first results from an ongoing initiative to develop a multi-millennial Baltic tree-ring width (TRW) chronology consisting of 12 floating records from subfossil Scots pines (Pinus sylvestris L.) extracted from three Lithuanian peat-mining areas. The floating series have been complemented with absolutely dated TRW chronologies which were obtained from living trees growing in

Mid- to Late Holocene climate transition and moisture dynamics inferred from South Swedish tree-ring data

A 1561-year tree-ring width (TRW) chronology covering the period 2668–1108 BC (4617–3057 BP) has been developed from 159 moisture-sensitive peatland pines (Pinus sylvestris L.) sampled at Åbuamossen, southern Sweden. Tree population dynamics and annual growth responses of the trees were shown to reflect and give absolute age to regional hydro-climatological changes. The main wet-shifts recorded inA 1561-year tree-ring width (TRW) chronology covering the period 2668–1108 BC (4617–3057 BP) has been developed from 159 moisture-sensitive peatland pines (Pinus sylvestris L.) sampled at Åbuamossen, southern Sweden. Tree population dynamics and annual growth responses of the trees were shown to reflect and give absolute age to regional hydro-climatological changes. The main wet-shifts recorded in

Increased tree establishment in Lithuanian peat bogs — Insights from field and remotely sensed approaches

Over the past century an ongoing establishment of Scots pine (Pinus sylvestris L.), sometimes at accelerating rates, is noted at three studied Lithuanian peat bogs, namely Kerėplis, Rėkyva and Aukštumala, all representing different degrees of tree coverage and geographic settings. Present establishment rates seem to depend on tree density on the bog surface and are most significant at sparsely cov

What Do Selectorates Seek? A Comparative Analysis of Belgian Federal and Regional Candidate Selection Processes in 2014

The 2014 “mother of all elections” in Belgium offers a unique opportunity to test whether candidate selection for regional and federal elections work alike or differently. The fact that Belgian “statewide” parties do not exist anymore and that Belgium is a quasi-closed list system, giving parties almost unlimited control over candidate selection enhances the uniqueness of the Belgian case. This ar

The New Belgian Senate. A (Dis)Continued Evolution of Federalism in Belgium?

The 2012–14 reform of the Belgian state has deeeply transformed its Senate. Not only does the reform reduce the legislative powers of the Belgian upper chamber, but it also alters its composition. The former appointment of Senators based on a system of direct and community-based election is replaced by a system of indirect and mixed regional and community-based designation. This article presents t

Gender Quotas and ‘Women-Friendly’ Candidate Selection: Evidence from Belgium

Belgium is one of the world leaders with regard to gender quotas, with strict rules for gender parity being imposed on political parties. Nonetheless the question remains as to whether these requirements for gender-equal list formation have led to women-friendly candidate selection procedures. Noting a gap in research on this topic, this article proposes a definition of ‘women-friendly’ candidate

Ions in models of articular cartilage : The importance of electrostatic interactions for transport and equilibrium distribution

Artros är en vanligt förekommande ledsjukdom som kan leda till stelhet ochsmärta i den drabbade leden. Sjukdomen innebär att det sker en nedbrytning av det brosk som fungerar som smörjmedel och skyddande lager runt benändarna i leden. Nedbrytningen av brosket sker gradvis under flera år och oftast upptäcker man sjukdomen först i ett sent stadium när man börjar känna smärta eller få problem med rörOsteoarthritis (OA) is a degenerative disease that affects articular cartilage, which covers the surfaces of the bones in synovial joints. At later stages the disease can result in major loss of articular cartilage and thus lead to major disability. In order to allow for an early detection and treatment of OA, it is necessary to better understand the rather subtle biochemical changes in the cartil

The Burden of Mental Disorders in the Eastern Mediterranean Region, 1990-2013

The Eastern Mediterranean Region (EMR) is witnessing an increase in chronic disorders, including mental illness. With ongoing unrest, this is expected to rise. This is the first study to quantify the burden of mental disorders in the EMR. We used data from the Global Burden of Disease study (GBD) 2013. DALYs (disability-adjusted life years) allow assessment of both premature mortality (years of li

Thermodynamic analysis of siphon flash evaporation desalination system using ocean thermal energy

Ocean thermal energy refers to the thermal potential energy produced by the temperature difference between the warm surface seawater and the cold deep seawater. In this paper, a siphon flash evaporation desalination system using ocean thermal energy is proposed. Because it can utilize the ocean thermal energy directly for desalination, siphon flash evaporation desalination system has relatively hi

Effects of pitch and corrugation depth on heat transfer characteristics in six-start spirally corrugated tube

Spirally corrugated tube is one of the most important parts of coaxial heat exchangers. It can greatly improve the heat transfer efficiency of heat exchangers. Here, a novel spirally corrugated tube with six-start is proposed. However, up to now, there is little literature about the heat transfer performance and flow field of this novel six-start spirally corrugated tube. In this paper, the effect

Field synergy analysis of six starts spiral corrugated tube under high Reynolds number

Coaxial heat exchanger is widely used in air conditioning, refrigeration etc., due to its highly efficient heat transfer performance. Spiral corrugated tube plays an important role in coaxial heat exchanger. In this paper, the numerical model of a six starts spiral corrugated tube and a smooth tube with the same size are developed. The temperature field and the velocity field of their streamline a

Dynamic response analysis of pilot control globe valve focusing on opening and closing time of pilot valve

Pilot control globe valve (PCGV) can use the pressure difference produced by fluid itself to realize the opening and closing states with a pilot valve. In this paper, numerical method is used to investigate the fluid flow characteristics and the valve core movement inside PCGV under different opening and closing times of pilot valve. The result shows that, shorter opening and closing time of valve

Hedging lookback and partial lookback options using Malliavin calculus

The paper considers a Black and Scholes economy with constant coefficients. A contingent claim is said to be simple if the payoff at maturity is a function of the value of the underlying security at maturity. To replicate a simple contingent claim one uses so called delta-hedging, and the well-known strategy is derived from Itô calculus and the theory of partial differentiable equations. However,