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Traveling or stopping of migrating birds in relation to wind: an illustration for the osprey

Although it is often assumed that birds strongly prefer tailwinds for their migratory flights, we predict that a strategy of no wind selectivity (traveling independently of winds) may be more favorable than wind selectivity (traveling on tailwind occasions but stopping to rest under headwind occasions) for birds with low energy costs of travel relative to rest and for birds that cannot use stopove

High Symbiont Relatedness Stabilizes Mutualistic Cooperation in Fungus-Growing Termites

It is unclear how mutualistic relationships can be stable when partners disperse freely and have the possibility of forming associations with many alternative genotypes. Theory predicts that high symbiont relatedness should resolve this problem, but the mechanisms to enforce this have rarely been studied. We show that African fungus-growing termites propagate single variants of their Termitomyces

Early posttraumatic pulmonary platelet trapping and its potentiation by oral pretreatment with alcohol

Soft tissue trauma is associated with platelet aggregation and sequestration in the lungs. This is believed to be an early step in the later development of adult respiratory distress syndrome. In the present experiment using a new method for in vivo dynamic studies of platelet sequestration, we wanted to evaluate the effect of soft tissue trauma on pulmonary platelet trapping in pigs and the influ

Microvascular response in guinea pig skin to histamine challenge with and without application of skin window.

We measured the microvascular response to histamine in guinea pig skin. Histamine (40 mg ml-1) was given either as a skin prick test or applied topically onto a skin window. The skin window was prepared by applying suction and gentle warming to the skin so that a blister was formed, and by removing the top of the blister. The microvascular response was measured as the accumulation of radiolabelled

Uneven distribution of repetitive trinucleotide motifs in human immunoglobulin heavy variable genes

Insertions and deletions of entire codons have recently been discovered as a mechanism by which B cells, in addition to conventional base substitution, evolve the antibodies produced by their immunoglobulin genes. These events frequently seem to involve repetitive sequence motifs in the antibody-encoding genes, and it has been suggested that they occur through polymerase slippage. In order to bett

Vortex wakes generated by robins Erithacus rubecula during free flight in a wind tunnel

The wakes of two individual robins were measured in digital particle image velocimetry (DPIV) experiments conducted in the Lund wind tunnel. Wake measurements were compared with each other, and with previous studies in the same facility. There was no significant individual variation in any of the measured quantities. Qualitatively, the wake structure and its gradual variation with flight speed wer

Distinctive functions of membrane type 1 matrix-metalloprotease (MT1-MMP or MMP-14) in lung and submandibular gland development are independent of its role in pro-MMP-2 activation

Membrane type 1-matrix metalloprotease (MT1-MMP or MMP-14) is a major activator of pro-MMP-2 and is essential for skeletal development. We show here that it is required for branching morphogenesis of the submandibular gland but not the lung. Instead, in the lung, it is essential for postnatal development of alveolar septae. Lung development in Mmp14-/- mice is arrested at the prealveolar stage wit

Medial Expression of TNF-α and TNF Receptors Precedes the Development of Atherosclerotic Lesions in Apolipoprotein E/LDL Receptor Double Knockout Mice

TNF-α is present in atherosclerotic lesions, activates endothelial adhesion molecule expression, stimulates the release of proinflammatory cytokines and matrix metalloproteinases and promotes smooth muscle cell proliferation and migration. Taken together these observations suggest that TNF-α may be functionally involved in early atherosclerosis development. To further evaluate this hypothesis we c

International politics: Scandinavian Identity Amidst American Hegemony?

International politics is often portrayed as a hegemonic discipline, dominated by US scholarship. Exploring the consequences of recent upheavals in world affairs for international politics research, the article suggests that the end of the cold war has exposed certain weaknesses in the US center which may be turned into advantages for the Scandinavian periphery. Specifically, Scandinavian research

Scholarly publishing and open access in the Nordic Countries

This study examines aspects of scholarly journal publishing in the Nordic countries. On average half of Nordic journals publish online. In most Nordic countries, commercial publishers predominate; however, in Finland the majority are society publishers. The number of open access journals is low, in line with international figures. There is concern to maintain local languages in journal publishing.

Composition and variations in the occurrence of dissolved free simple organic compounds of an unproductive lake ecosystem in northern Sweden

Low molecular weight organic carbon compounds are potentially important carbon and energy substrates to heterotrophic production in the aquatic environment. We studied the occurrence of dissolved free amino acids (AA), monosaccharides (CHO), and carboxylic acids (CA) in the subarctic Lake Diktar-Erik. The lake is unproductive with slightly humic water, and receives water via one major inlet stream

Ring-theoretic properties of commutative algebras of invariants

The commutative algebra of invariants of a Lie super-algebra need not be affine, but does have a common ideal with an affine algebra, in all the known examples. This leads us to extend a class of algebras C to a class which we call "nearly C", by admitting those algebras C having a common ideal A with an algebra (containing C) in C such that C/A is an element of C. We generalize this notion slight

Novel mutations in the SLC12A3 gene causing Gitelman's syndrome in Swedes

PURPOSE: Gitelman's syndrome (GS) is an inherited autosomal recessive disorder due to loss of function mutations in the SLC12A3 gene encoding the Na-Cl co-transporter (NCCT), the target of thiazide diuretics. The defective function of the NCCT, which normally is expressed in the apical membrane of the distal convolute tubule in the kidney, leads to mild hypotension, hypokalemia, hyperreninemic hyp

Interaction between Aqueous Uranium(Vi) and Sulfide Minerals - Spectroscopic Evidence for Sorption and Reduction

The interaction of aqueous U(VI) with galena and pyrite surfaces under anoxic conditions has been studied by solution analysis and by spectroscopic methods. The solution data indicate that uranyl uptake is strongly dependent on pH; maximum uptake (>98%) occurs above a pH range of between 4.8 and 5.5, depending on experimental conditions. Increasing the sorbate/sorbent ratio results in a relative d

Rat insulin promoter 2-Cre recombinase mice bred onto a pure C57BL/6J background exhibit unaltered glucose tolerance

beta-Cell-specific gene targeting is a widely used tool when studying genes involved in beta-cell function. For this purpose, several conditional beta-cell knockouts have been generated using the rat insulin promoter 2-Cre recombinase (RIP2-Cre) mouse. However, it was recently observed that expression of Cre alone in P-cells may affect whole body glucose homeostasis. Therefore, we investigated glu

Impact of metformin versus the prandial insulin secretagogue, repaglinide, on fasting and postprandial glucose and lipid responses in non-obese patients with type 2 diabetes

Objective: Non-obese patients with type 2 diabetes (T2DM) are characterized by predominant defective insulin secretion. However, in non-obese T2DM patients, metformin, targeting insulin resistance. is non-inferior to the prandial insulin secretagogue, repaglinide, controlling overall glycaemia (HbA(1c)). Whether the same apply for postprandial glucose and lipid metabolism is unknown. Here. we comp

Large variations in the propensity of aqueous oxychlorine anions for the solution/vapor interface

Core-level photoelectron spectroscopy measurements have been performed of aqueous solutions of NaCl codissolved with NaClOn (n=1-4). Each species has a distinct Cl 2p electron binding energy, which can be exploited for depth-profiling experiments to study the competition between Cl-and ClOn- anions for residing in the outermost layers of the solution/vapor interface. Strongest propensity for the s