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Persistent link between solar activity and Greenland climate during the Last Glacial Maximum

Changes in solar activity have previously been proposed to cause decadal- to millennial-scale fluctuations in both the modern and Holocene climates(1). Direct observational records of solar activity, such as sunspot numbers, exist for only the past few hundred years, so solar variability for earlier periods is typically reconstructed from measurements of cosmogenic radionuclides such as Be-10 and

Centrifugation as pretreatment before ultrafiltration of hemicelluloses extracted from wheat bran

Hemicelluloses recovered by alkaline extraction of wheat bran can be isolated and purified by ultrafiltration and used to produce high-value products such as barrier films for food packaging. The flux during ultrafiltration depends to a large extent on the pretreatment of the solution. It has been shown previously that dead-end filtration with kieselguhr can increase the flux during ultrafiltratio

Size selective capture of Atlantic cod (Gadus morhua) in floating pots

Little is known about the size selectivity of cod in static fishing gears such as pots and traps. In this field study, floating fishing pots were equipped with 40, 45 and 50 mm square mesh escape windows in order to estimate the size selectivity of cod at different mesh sizes. Relationships between selectivity parameters and mesh size, as well as an optimal mesh size for the escape window with res

Combined gene overexpression of neuropeptide Y and its receptor Y5 in the hippocampus suppresses seizures

We recently demonstrated that recombinant adeno-associated viral vector-induced hippocampal overexpression of neuropeptide Y receptor, Y2, exerts a seizure-suppressant effect in kindling and kainate-induced models of epilepsy in rats. Interestingly, additional overexpression of neuropeptide Y in the hippocampus strengthened the seizure-suppressant effect of transgene Y2 receptors. Here we show for

The Impact of Social Beliefs on Microfinance Performance

We apply a panel of 331 microfinance institutions from 37 countries to investigate the relationship between social beliefs and microfinance financial performance over the period of 2003-2011. We find that microfinance institutions in countries with higher levels of trust and more collectivist culture have lower operating and default costs and charge lower interest rates. These results provide the

Search for high-mass resonances decaying to dilepton final states in pp collisions at root s=7 TeV with the ATLAS detector

The ATLAS detector at the Large Hadron Collider is used to search for high-mass resonances decaying to an electron-positron pair or a muon-antimuon pair. The search is sensitive to heavy neutral Z' gauge bosons, Randall-Sundrum gravitons, Z* bosons, techni-mesons, Z/gamma bosons, and bosons predicted by Torsion models. Results are presented based on an analysis of pp collisions at a center-of-mass

Added value in regional climate modeling

Regional climate modeling is a dynamical downscaling technique applied to the results of global climate models (GCMs) in order to acquire more information on climate simulations and climate change projections. GCMs and regional climate models (RCMs) have undergone considerable development over the past few decades, and both have increased in resolution. The higher-resolution edge of RCMs compared

Activity of Ancient RTE Retroposons during the Evolution of Cows, Spiral-Horned Antelopes, and Nilgais (Bovinae)

In the genome of Artiodactyla (cow, sheep, pigs, camels, and whales), a major retroposon group originated from a presumable horizontal transfer of BovB, a retrotransposon-like element retroposon, between 52 and 70 million years ago. Since then, BovB retroposons have proliferated and today occupy a quarter of the cow's genome sequence. The BovB-related short interspersed elements (SINEs) were used

An Isolated High-Power Integrated Charger in Electrified-Vehicle Applications

For electric and hybrid vehicles that use grid power to charge the battery, traction circuit components are not normally engaged during the charging time; hence, there is a possibility of using the traction circuit components in the charger circuit to have an onboard integrated charger. An isolated high-power integrated charger based on a special electrical machine with a double set of stator wind

CCRL1/ACKR4 is expressed in key thymic microenvironments but is dispensable for T lymphopoiesis at steady state in adult mice

Thymus colonisation and thymocyte positioning are regulated by interactions between CCR7 and CCR9, and their respective ligands, CCL19/CCL21 and CCL25. The ligands of CCR7 and CCR9 also interact with the atypical receptor CCRL1 (also known as ACKR4), which is expressed in the thymus and has recently been reported to play an important role in normal alpha beta T-cell development. Here, we show that

On total traffic domination in non-complete graphs

Abstract in Undetermined Given an undirected graph g(V, E), a set of traffic matrices H and one additional traffic matrix h, we say that H totally dominates h if, for each capacity reservation u supporting H, u also supports h using the same routing pattern. It has been shown that if vertical bar H vertical bar = 1 = (H = {(h) over cap}, say) and g, is a complete graph, H totally dominates h if, a

Dominant impact of water exchange and disruption of stratification on dinoflagellate vertical distribution

The vertical positions of four dinoflagellate species in three 48 h periods in late summer in a Swedish fjord (the Gullmar Fjord) reflect changes to the depth of the halocline. During stable, stratified conditions, the chlorophyll a maximum exhibited a diurnal migration pattern, which was disrupted when the halocline was forced closer to the surface by the inflow of more saline water. While condit

InP Nanowire Array Solar Cells Achieving 13.8% Efficiency by Exceeding the Ray Optics Limit.

Photovoltaics based on nanowire arrays could reduce cost and materials consumption compared to planar devices, but have exhibited low efficiency of light absorption and carrier collection. We fabricated a variety of millimeter-sized arrays of p-i-n doped InP nanowires and found that the nanowire diameter and the length of the top n-segment were critical for cell performance. Efficiencies up to 13.

Management of natural resources in a conflicting environment in Ghana: unmasking a messy policy problem

Resource use conflict is an enduring problem for science and policy making. Using in-depth interviews and focus group discussions with resource users, policy makers and key informants, we explored four case examples of resource use conflict within lands and forestry, fisheries, oil and the mining sectors in Ghana. Results indicate that resource use conflict consists of a complex, non-linear system

Model-free estimation of the effective correlation time for C-H bond reorientation in amphiphilic bilayers: (1)H-(13)C solid-state NMR and MD simulations.

Molecular dynamics (MD) simulations give atomically detailed information on structure and dynamics in amphiphilic bilayer systems on timescales up to about 1 μs. The reorientational dynamics of the C-H bonds is conventionally verified by measurements of (13)C or (2)H nuclear magnetic resonance (NMR) longitudinal relaxation rates R1, which are more sensitive to motional processes with correlation t

Cigarette smoke attenuates the nasal host response to Streptococcus pneumoniae and predisposes to invasive pneumococcal disease in mice.

Streptococcus pneumoniae is a leading cause of invasive bacterial infections, with nasal colonization an important first step for disease. While cigarette smoking is a strong risk factor for invasive pneumococcal disease, underlying mechanisms remain unknown. This is partly due to a lack of clinically relevant animal models investigating nasal pneumococcal colonization in the context of cigarette

Invasive plant species in the Swedish flora: developing criteria and definitions, and assessing the invasiveness of individual taxa

In a north European context, identifying invasive species is far from trivial because the vegetation has been influenced by human activities for thousands of years. New species have immigrated continuously since the end of the last glaciation, both spontaneously and through direct or indirect help by man. Still, newly immigrated species may be problematic in a nature conservation context and may h