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Astrophysical lasers and nonlinear optical effects in space

The present state of the art concerning astrophysical lasers (APL) and nonlinear optical effects under astrophysical conditions is reviewed. The operational conditions of an APL (amplification under non-LTE conditions) and astrophysical predecessors of the laboratory lasers are considered in the introduction of the review. The rareness of observed APL action in the visible range in comparison with

Genetic origin and success of reintroduced white storks

After their local extinction in 1954, White Storks (Ciconia ciconia) were reintroduced to Sweden in 1989. The founder Population for the reintroduced birds originated in North Africa, rather than from the closest breeding population in northeastern Europe (defined here as native). A number of wild storks have immigrated spontaneously, and a few others of native origin have been acquired for captiv

Cross-sectional dependency and size distortion in a small-sample homogeneous panel data unit root test

In this paper, we investigate the effects of cross-sectional disturbance correlation in a homogeneous panel data unit root test. As reported by other authors, the unit root test has incorrect size in the presence of cross-sectional correlation. We suggest that a previously known estimator can be used to reduce the size distortions. We supply response surface estimates for critical values and study

A DNA marker for the duplicated cytosolic PGI genes in sheep's fescue (Festuca ovina L.)

Active duplicate PgiC genes in sheep's fescue, Festuca ovina, are associated with a PCR marker of specific length (about 370 bp, of which 231 are in an intron). Using this marker, the frequency of plants with duplicate genes is estimated to be about 10% in a population from southern Sweden. The close molecular similarity between the electrophoretically different duplicated genes is in accordance w

Possible role of reactive chlorine in microbial antagonism and organic matter chlorination in terrestrial environments.

Summary Several studies have demonstrated that extensive formation of organically bound chlorine occurs both in soil and in decaying plant material. Previous studies suggest that enzymatic formation of reactive chlorine outside cells is a major source. However, the ecological role of microbial-induced extracellular chlorination processes remains unclear. In the present paper, we assess whether or

Individual self-reported health, social participation and neighbourhood: a multilevel analysis in Malmö, Sweden.

Background. The influence of neighbourhood and individual factors on self-reported health was investigated. Methods. The public health survey in Malmö 1994 is a cross-sectional study. A total of 3,602 individuals aged 20–80 living in 75 neighbourhoods answered a postal questionnaire. The participation rate was 71%. A multilevel logistic regression model, with individuals at the first level and ne

Compliance and findings in a Swedish population screened for colorectal cancer with sigmoidoscopy

Aim: The aim of this study was to evaluate the patterns of compliance and the frequency of adenomas and neoplasms in a Swedish population. Methods: In 1996, 2000 men and women born in 1935 or 1936 were selected at random from the population registers of Uppsala and Malmo/Lund. All subjects were invited by mail to participate. In a randomised study design, subjects were either called up by a nurse

Timing analysis and simulation tools for real-time control

Abstract in UndeterminedThe temporal non-determinism introduced by computing and communication in the form of delay and jitter can lead to significant performance degradation. To achieve good performance in systems with limited computer resources, e.g. embedded systems, the resource constraints of the implementation platform must be taken into account at design time. To facilitate this, software t

Quantum chemical calculations show that the uranium molecule U-2 has a quintuple bond

Covalent bonding is commonly described by Lewis's theory(1), with an electron pair shared between two atoms constituting one full bond. Beginning with the valence bond description(2) for the hydrogen molecule, quantum chemists have further explored the fundamental nature of the chemical bond for atoms throughout the periodic table, confirming that most molecules are indeed held together by one ele

Serum calcium and breast cancer risk: results from a prospective cohort study of 7,847 women.

Experimental and epidemiological studies suggest that calcium-regulating hormones-parathyroid hormone (PTH) and vitamin D-may be associated with breast cancer risk. No prospective cohort study has investigated the association between pre-diagnostic calcium levels and subsequent risk of breast cancer. We have examined this in a cohort of 7,847 women where serum calcium levels and established risk f

The patella in total knee arthroplasty: resurfacing or nonresurfacing of patella

Data from the Swedish Knee Arthroplasty Registry were analyzed to compare bi- and tricompartmental knee arthroplasties carried out in patients operated on for arthrosis in 1990-1996. Of the 16,607 primary arthroplasties that were carried out there were 5,139 with patellar replacement in the primary procedure and 10,928 without. By April 1998, 280 revisions were performed, 250 of these cases were a

Attenuation of electrical remodelling in chronic atrial fibrillation following oral treatment with verapamil

AIMS: Electrical remodelling with shortening of the atrial refractory period and increased fibrillatory rate occurs after onset of atrial fibrillation and can be attenuated by pre-treatment with intravenous verapamil. The aim of the present study was to investigate whether already established fibrillatory-induced shortening of atrial fibrillatory cycle length could be reversed with oral verapamil.

Measurement of the sign of the spectroscopic quadrupole moment for the 2(1)(+) state in Se-70: No evidence for oblate shape

Using a method whereby molecular and atomic ions are independently selected, an isobarically pure beam of Se-70 ions was postaccelerated to an energy of 206 MeV using REX-ISOLDE. Coulomb-excitation yields for states in the beam and target nuclei were deduced by recording deexcitation gamma rays in the highly segmented MINIBALL gamma-ray spectrometer in coincidence with scattered particles in a sil

Direct molecular weight determination in the evaluation of dissolution methods for unreduced glutenin

A comparison of two dissolution methods, gentle stirring and sonication, for solubilising the ultra-large wheat protein glutenin was made based on a direct determination of the molecular weight of dissolved glutenin. The possible physical breakdown of glutenin by sonication was evaluated. Glutenin was isolated by extraction with hydrochloric acid and freeze dried. The extracted glutenin was dissol

Translational machinery and protein folding: Evidence of conformational variants of the estrogen receptor alpha

As an approach to understand how translation may affect protein folding, we analyzed structural and functional properties of the human estrogen receptor alpha synthesized by different eukaryotic translation systems. A minimum of three conformations of the receptor were detected using limited proteolysis and a sterol ligand-binding assay. The receptor in vitro translated in rabbit reticulocyte lysa

Verification of a dynamic wedge implementation in a pencil beam based dose planning system

The use of dynamic movements on linear accelerators during irradiation have found a revised interest lately due to the integration of computers to control the linear accelerator. An example of this is the generation of fields that resemble ordinary wedge fields. These fields are produced by moving one of the collimator blocks during irradiation, i. e. dynamic wedges.A pencil beam based system with

Association of cysteine-rich secretory protein 3 and beta-microseminoprotein with outcome after radical prostatectomy

Purpose: It has been suggested that cysteine-rich secretory protein 3 (CRISP-3) and p-microseminoprotein (MSP) are associated with outcome in prostate cancer. We investigated whether these markers are related to biochemical recurrence and whether addition of the markers improves prediction of recurring disease. Experimental Design: Tissue microarrays of radical prostatectomy specimens were analyze