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1. Net primary production (NPP) by terrestrial ecosystems appears to be proportional to absorbed photosynthetically active radiation (APAR) on a seasonal and annual basis. This observation has been used in 'diagnostic' models that estimate NPP from remotely sensed vegetation indices. In 'prognostic' process-based models carbon fluxes are more commonly integrated with respect to leaf area index ass

During liquefaction of the ejaculate, the semen coagulum proteins semenogelin I (SEMG1) and semenogelin II (SEMG2) are degraded to low molecular mass fragments by kallikrein-related peptidase 3 (KLK3), also known as prostate-specific antigen. Semenogelin molecules initiate their own destruction by chelating Zn2+ that normally would completely inhibit the proteolytic activity of KLK3. In a similar

Using a statistical methodology, we aimed to identify a group of probable cases of oculo-auriculo-vertebral (OAV) dysplasia and to investigate possible relationships between different patterns of congenital malformations. Among 5,260 infants with multiple malformations collected from 4 large registers of congenital malformations, we identified 312 probable OAV cases. With the same technique, we ha

Collagen induced arthritis (CIA) is a common mouse model for rheumatoid arthritis. Two sets of truncated peptides derived from type II collagen have been prepared and tested for binding to A(q), a MHC-II molecule associated with development of CIA. Binding to A(q) correlated well with predictions from a computer-based model. T-cell hybridomas, obtained in CIA, were also used to study the ability o

During hypoglycaemia, counter-regulatory hormones are released, cognitive function is impaired and cerebral blood flow is increased. In the immediate period after normalisation of blood glucose only counter-regulatory hormones seem to be normalised. The aim of this study was to follow the changes in cerebral blood flow during a prolonged recovery period following moderate hypoglycaemia in normal m

Values of deltaC-13 obtained from conventional bulk sediment radiocarbon dates encompassing the Pleistocene-Holocene boundary have been compiled and plotted against C-14 age. In all, 286 lake sediment dates from southern Sweden in the range 8,000 to 13.000 BP have been evaluated. A significant decrease in deltaC-13 values, initiated shortly before 10,000 BP and amounting to 5 parts per thousand, i

In 1993 and 1994, the relation between breast size and hormonal factors and body constitution was studied in 65 healthy nulligravid women aged 19-25 years. Twenty-five women were current oral contraceptive users, 20 women were former users, and 20 women had never used oral contraceptives. Breast size was strongly positively correlated with current oral contraceptive use during menstrual cycle days

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

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

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

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

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

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

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

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 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

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.

We report spatially and time-resolved measurements of ultrafast carrier dynamics around buried nano-scale Schottky contacts, performed with a novel femtosecond near-field scanning optical microscope. The experimental results are modeled by a self-consistent treatment of the drift-diffusion equation for the carriers and Poisson's equation for the built-in electric field. We show that the built-in f

Soon after coming in contact with its host, the plant pathogenic fungus Bipolaris sorokiniana produces an extracellular material that appears to be important for adhering conidia and germlings to the host surface. To further understand this step of the infection, the adhesion of B. sorokiniana to artificial solid surfaces was examined. On a hydrophobic (polystyrene) surface adhesion occurred in tw