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Late Holocene wetland transgression and 500 years of vegetation and fire variability in the semi-arid Amboseli landscape, southern Kenya

The semi-arid Amboseli landscape, southern Kenya, is characterised by intermittent groundwater-fed wetlands that form sedimentary geoarchives recording past ecosystem changes. We present a 5000-year environmental history of a radiocarbon dated sediment core from Esambu Swamp adjacent to Amboseli National Park. Although radiocarbon dates suggest an unconformity or sedimentary gap that spans between

Foreword of the KB Broberg symposium issue : Second KBB symposium held at the Trolleholm Castle in Svalöv, Sweden, 2009

To honour the memory of Knut Bertram Broberg, and to promote continuing work on the many ideas which he shared so generously with students and colleagues throughout his lifetime, a symposium was arranged at University College of Dublin in 2007. The idea was to create an informal atmosphere, and to keep the num- ber of participants fairly low. This has now become a bi-annual symposium with the high

Spontaneous fracture of growing precipitates with large misfit strain

Precipitates that form as a result of phase transformation are studied with regard to mechanical behaviour and initiation of internal cracks. The focus is on precipitates occupying a larger volume than the surrounding matrix. Further the study is restricted to precipitates growing by incorporating material transformed from being matrix material to the phase of the precipitate. The phase transforma

Indoor-to-outdoor ratios of ultrafine particles in Swedish residences

A number of health effects have been linked to exposure to airborne particles, however the consequences of exposure to ultrafine particles is largely unknown. Ultrafine particles can be emitted from different indoor activities or be of the outdoor origin. This is further complicated by the fact that we are spending majority of the time indoors. The aim of this work was to assess the influence of r

Application of positive matrix factorization (PMF) to real time aerosol mass spectrometry measurements in an occupied apartment in Sweden

Introduction Given that in developed countries we spend about 65% of our time in private homes (Brasche et al. 2005), understanding the exposures in homes is of outmost importance. Airborne particle concentrations indoors can be affected by particles of indoor and outdoor origins, as well as physico-chemical processes indoors, outdoor infiltration affected by tightness of the building envelope and

Influence of the cavity field flatness and effect of the phase reference line errorson the beam dynamics of the ESS LINAC

The particle longitudinal dynamics is affected by errors on the phase and amplitude of the electro-magnetic field in each cavity that cause emittance growth, beam degradation and losses. One of the causes of the phase error is the change of the ambience temperature in the LINAC tunnel, in the stub and in the klystron gallery that induces a phase drift of the signal travelling through the cables an

Beam dynamics of the ESS linac

The ESS linac will deliver an unprecedented 5 MW of average beam power when completed. Beyond the 90 MeV normal conducting front-end, the acceleration is performed using superconducting structures up to the design energy of 2 GeV. As the ESS will send the beam to a fixed tungsten target, the emittance is not as important a factor as in injectors. However, the losses have to be studied in detail, i

ESS commissioning plans

The ESS linac is currently under construction in Lund, Sweden, and once completed it will deliver an unprecedented 5 MW of average power. The ion source and LEBT commissioning starts in 2018 and will continue with the RFQ, MEBT and the frst DTL tank next year and up to the end of the fourth DTL tank in 2020. This paper will summarize the commissioning plans for the normal conducting linac with foc

QUAPEVA : Variable high gradient permanent magnet quadrupole

The magnetic and the mechanical design of a high and variable gradient Permanent Magnet Quadrupole (PMQ) is presented. Seven of them with various lengths, ranging from 26 mm up to 100 mm, for different integrated quadrupole strengths were manufactured. The measured magnetic performance of these devices is also reported. These devices were successfully commissioned to transport laser plasma acceler

5-hydroxytryptamine in the endocrine pancreas

The presence of serotonin (5-hydroxytryptamine [5-HT]) in pancreatic endocrine cells is well established. Nevertheless, recent advances are only now unraveling the signaling network involving 5-HT that partly regulates the release of hormones emanating from the islets of Langerhans. It is widely accepted that failure of the pancreatic β-cell to release sufficient amounts of insulin is the main cul

Serotonin and adipocyte function

The ability to store and mobilize energy is fundamental for physiologic function. Most excess energy is stored in adipose tissue as triglycerides, which is released as free fatty acids when needed through cellular processes tightly regulated by insulin. Intact adipose cell function is essential to regulate whole-body glucose and lipid metabolism. Several studies have focused on the metabolic impac