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Two mechanisms for dissipation of excess light in monomeric and trimeric light-harvesting complexes

Oxygenic photoautotrophs require mechanisms for rapidly matching the level of chlorophyll excited states from light harvesting with the rate of electron transport from water to carbon dioxide. These photoprotective reactions prevent formation of reactive excited states and photoinhibition. The fastest response to excess illumination is the so-called non-photochemical quenching which, in higher pla

Visual acuity of the honey bee retina and the limits for feature detection

Visual abilities of the honey bee have been studied for more than 100 years, recently revealing unexpectedly sophisticated cognitive skills rivalling those of vertebrates. However, the physiological limits of the honey bee eye have been largely unaddressed and only studied in an unnatural, dark state. Using a bright display and intracellular recordings, we here systematically investigated the angu

Mobility and Regionalisation : Changing patterns of air traffic in the Baltic Sea Region in connection to European Integration

The geo-political transition in 1989-91 had long term consequences for the European integration process. The integration and regionalisation processes following the transition resulted in a transformation of territorial borders in and around the region; the functions of the borders changed. Mobility is vital for these processes. This paper is based on a longitudinal study of the development of air

Theoretical simulations of oxygen K -edge resonant inelastic x-ray scattering of kaolinite

Near-edge x-ray absorption fine structure (NEXAFS) and resonant inelastic x-ray scattering (RIXS) measurements at the oxygen K edge were combined with theoretical spectrum simulations, based on periodic density functional theory and nuclear quantum dynamics, to investigate the electronic structure and chemical bonding in kaolinite Al2Si2O5(OH)4. We simulated NEXAFS spectra of all crystallographica

Ames Waltzer deaf mice have reduced electroretinogram amplitudes and complex alternative splicing of Pcdh15 transcripts

PURPOSE: Mutations of PCDH15, the gene encoding protocadherin 15, cause either nonsyndromic deafness DFNB23 or Usher syndrome type 1F (USH1F) in humans and deafness with balance problems in Ames waltzer (av) mice. Persons with USH1 usually begin to exhibit signs of retinitis pigmentosa (RP) in early adolescence, but av mice are reported to have functional retinas. In this study, the auditory, visu

NF1-mutated melanoma tumors harbor distinct clinical and biological characteristics

In general, melanoma can be considered as a UV-driven disease with an aggressive metastatic course and high mutational load, with only few tumors (acral, mucosal, and uveal melanomas) not induced by sunlight and possessing a lower mutational load. The most commonly activated pathway in melanoma is the mitogen-activated protein kinase (MAPK) pathway. However, the prognostic significance of mutation

Cesarean section trends in the Nordic Countries - a comparative analysis with the Robson classification

Introduction: The cesarean rates are low but increasing in most Nordic countries. Using the Robson classification, we analyzed which obstetric groups have contributed to the changes in the cesarean rates. Material and methods: Retrospective population-based registry study including all deliveries (3 398 586) between 2000 and 2011 in Denmark, Finland, Iceland, Norway and Sweden. The Robson group di

Peatland dynamics in response to past and potential future climate change : A regional modelling approach

En majoritet av de nordliga torvmarkerna utvecklades under holocen som ett resultat av en positiv massbalans mellan nettoprimärproduktion och heterotrofa nedbrytningshastigheter. Sedan dess har de lagrat stora mängder kol i terrestra ekosystem. En betydande del av dessa områden sammanfaller också med regioner med underliggande permafrost och uppvisar olika ackumulationsmönster av torv. Således, föThe majority of the northern peatlands developed during the Holocene as a result of a positive mass balance between net primary productivity (NPP) and heterotrophic decomposition rates. Over that time they have sequestered a huge amount of carbon in terrestrial ecosystems. A significant proportion of these areas also coincides with areas underlain with permafrost and shows a diverse range of peat

Core level photoelectron spectroscopy probed heterogeneous xenon/neon clusters

Binary rare gas clusters; xenon and neon which have a significant contrariety between sizes, produced by a co-expansion set up and have been studied using synchrotron radiation based x-ray photoelectron spectroscopy. Concentration ratios of the heterogeneous clusters; 1%, 3%, 5% and 10% were controlled. The core level spectra were used to determine structure of the mixed cluster and analyzed by co

Precambrian gold mineralization at Djamgyr in the Kyrgyz Tien Shan : Tectonic and metallogenic implications

The Djamgyr gold deposit is located within the Neoproterozoic basement of the Middle Tien Shan terrane immediately west of the Talas-Fergana fault. The deposit comprises a system of auriferous quartz veins cross-cutting the Beshtor plagiogranite. The veins are surrounded by hydrothermal alteration aureoles and are oriented parallel to the Talas-Fergana fault. The Beshtor granite sampled in the vic